Eight-speed transmission control system and control method thereof

Abstract

The present invention relates to an eight-speed transmission control system and a control method thereof, comprising a first control oil circuit connected to a first oil chamber of control clutches K1 and K2, a second control oil circuit connected to a second oil chamber of control clutches K2 and K3, and a third control oil circuit connected to a third oil chamber of control clutches K5 and K6, wherein the first control oil circuit, the second control oil circuit, and the third control oil circuit are arranged in parallel; a proportional valve and a three-position four-way solenoid valve are arranged on the first control oil circuit, the second control oil circuit, and the third control oil circuit, and the A and B interfaces of the three-position four-way solenoid valve are respectively connected to the two ends of the corresponding oil chamber; and a balancing oil circuit for balancing the pressure difference at the two ends of the first oil chamber, the second oil chamber, and the third oil chamber is also included. The eight-speed transmission control system is reasonably designed and highly practical. The balancing oil circuit is designed to balance the pressure difference at the two ends of the oil chamber when switching gears, so that the piston in the oil chamber moves slowly, and then the clutch can be slowly engaged, ensuring a smooth shifting process.

Description

Technical Field

[0001] The invention relates to an eight-speed transmission control system and a control method thereof. Background Art

[0002] The clutch in the eight-speed transmission uses a multi-plate friction clutch, which uses hydraulic oil to push the piston in the oil chamber to press the piston against the pressure plate to achieve engagement. However, the current hydraulic control system for the eight-speed transmission has design defects. When shifting gears, the large pressure difference between the two ends of the oil chamber causes the piston to move too fast, resulting in an unstable shifting process and prone to jerkiness. In addition, when two clutches are switched at the same time, the hydraulic system may have problems with insufficient oil volume or oil pressure, resulting in a slow shifting response speed. Summary of the invention

[0003] In view of this, the purpose of the present invention is to provide an eight-speed transmission control system and a control method thereof with a reasonable design and strong practicality, which can balance the pressure difference at both ends of the oil chamber when switching gears to ensure a smooth gear shifting process.

[0004] The present invention is implemented by the following scheme: an eight-speed transmission control system, characterized in that: it includes a first control oil circuit connected to the first oil chamber of the control clutches K1 and K2, a second control oil circuit connected to the second oil chamber of the control clutches K2 and K3, a third control oil circuit connected to the third oil chamber of the control clutches K5 and K6, and a fourth control oil circuit connected to the fourth oil chamber of the control clutch KF, the first control oil circuit, the second control oil circuit, the third control oil circuit and the fourth control oil circuit are arranged in parallel; the first control oil circuit, the second control oil circuit and the third control oil circuit are all provided with a proportional valve and a three-position four-way solenoid valve, and the A and B interfaces of the three-position four-way solenoid valve are respectively connected to the two ends of the corresponding oil chamber; the fourth control oil circuit is provided with a proportional valve; and it also includes a balancing oil circuit for balancing the pressure difference at the two ends of the first oil chamber, the second oil chamber and the third oil chamber.

[0005] Furthermore, the first control oil circuit, the second control oil circuit, the third control oil circuit, the fourth control oil circuit and the balance oil circuit are connected to the oil tank through the control main oil circuit, and the oil tank is also connected to the lubrication main oil circuit, and the lubrication main oil circuit is connected to the lubrication branch oil circuit leading to each lubrication oil channel, and the lubrication main oil circuit is provided with a filter element, a one-way valve and a two-position two-way solenoid valve, and the lubrication main oil circuit is also connected to a supplementary oil circuit leading to the control main oil circuit between the one-way valve and the two-position two-way solenoid valve.

[0006] Furthermore, a proportional valve and a normally closed two-position three-way solenoid valve are provided on the balancing oil circuit, the 2 interface of the two-position three-way solenoid valve is connected to one of the lubrication branch oil circuits, the 3 interface of the two-position three-way solenoid valve is connected to the proportional valve on the balancing oil circuit, and the 1 interface of the two-position three-way solenoid valve is respectively connected to the T interface of the three-position four-way solenoid valve on the first control oil circuit, the second control oil circuit and the third control oil circuit.

[0007] Furthermore, a filter element and a one-way valve are also provided on the control main oil circuit; the control main oil circuit is also connected to a pressure relief pipeline returning to the oil tank, and the pressure relief pipeline has a normally closed throttle valve and a relief valve arranged in parallel.

[0008] Furthermore, a pressure sensor A and a filter are connected to the lubrication main oil circuit; a metering pump driven by a high-speed motor is installed on the lubrication main oil circuit and the control main oil circuit, a heater and an oil suction filter are installed on the connecting pipeline between the oil tank and the control main oil circuit and the lubrication main oil circuit, a radiator is installed in the oil tank, and a breathable cap is provided on the upper side of the oil tank.

[0009] Furthermore, filters and pressure sensors B are installed on the pipelines between the three-position four-way solenoid valves and the corresponding oil chambers in the first control oil circuit, the second control oil circuit and the third control oil circuit; filters and pressure sensors B are also installed on the pipelines between the proportional valve and the fourth oil chamber in the fourth control oil circuit.

[0010] Another technical solution of the present invention: A control method of the eight-speed transmission control system as described above, comprising the following steps: (1) in the initial state, all proportional valves and solenoid valves are de-energized; (2) at the start of gear shifting, all proportional valves are given a specified voltage, the oil supply pressure of the proportional valves in the first control oil circuit, the second control oil circuit and the third control oil circuit is slightly greater than the oil supply pressure of the proportional valves in the balancing oil circuit, the three-position four-way solenoid valves in the first control oil circuit, the second control oil circuit and the third control oil circuit are energized respectively, and the two-position three-way solenoid valves and the two-position three-way solenoid valves are energized; at this time, the first control oil circuit, the second control oil circuit and the third control oil circuit supply oil to one end of the first oil chamber, the second oil chamber and the third oil chamber respectively, and one of the clutches K1 and K2 is closed. The clutch is closed, one of the clutches K3 and K4 is closed, and one of the clutches K5 and K6 is closed; the proportional valve on the balancing oil circuit supplies oil to the other end of the first oil chamber, the second oil chamber and the third oil chamber respectively through the two-position three-way solenoid valve. At the same time, the proportional valve on the fourth control oil circuit is energized according to a predetermined curve to supply oil to the fourth oil chamber; (3) During the closing process of the clutch, the voltage of the proportional valves of the first control oil circuit, the second control oil circuit, the third control oil circuit and the balancing oil circuit is continuously adjusted to increase the pressure difference between the two ends of the first, second and third oil chambers, and finally reaches a required pressure difference to make the clutch completely closed; then the proportional valve on the balancing oil circuit, the two-position three-way solenoid valve and the two-position three-way solenoid valve are energized to complete a gear shifting process.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] (1) Reasonable design and strong practicality. The balanced oil circuit can balance the pressure difference at both ends of the oil chamber when shifting gears, so that the piston in the oil chamber moves slowly, and the clutch can be engaged slowly, ensuring a smooth shifting process;

[0013] (2) A portion of the oil in the lubrication oil circuit is used to fill the control oil circuit so that the control oil circuit is full of oil. When the clutch needs to be controlled to switch gears, the main oil circuit only needs to provide the amount of oil required for the piston to move. This can speed up the response.

[0014] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below through specific embodiments and related drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the control system of an embodiment of the present invention;

[0016] Figure 2 Schematic diagram of the structure of the control system of the embodiment of the present invention at the transmission main valve block A;

[0017] Figure 3 Schematic diagram of the structure of the control system of the embodiment of the present invention at the transmission main valve block B;

[0018] Figure 4 yes Figure 1 Schematic diagram of the local structure of the lower part;

[0019] Figure 5 is a schematic diagram of the structure of an eight-speed transmission controlled by a control system according to an embodiment of the present invention;

[0020] Explanation of the numbers in the figure: 1-oil tank, 2-radiator, 3-breathable cap, 4-heater, 5-oil suction filter, 6-high-speed motor, 7-dosing pump, 8-transmission auxiliary valve block A, 9-20um filter element, 10-10um filter element, 11-throttle valve, 12-relief valve, 13-pressure measuring joint, 14-pressure measuring sensor C, 15-check valve, 16-transmission main valve block A, 17-supplementary oil circuit, 18-proportional valve, 19-three-position four-way solenoid valve, 20-pressure sensor B, 21 filter element, 22-two-position three-way solenoid valve, 23-two-position two-way solenoid valve, 24-transmission auxiliary valve block B, 25-transmission main valve block B, 26-filter, 27-mechanical platform valve block, 28-pressure sensor A, 29-throttle plug, 30-first oil chamber, 31-second oil chamber, 32-third oil chamber, 33-fourth oil chamber, 34-pressure sensor D. DETAILED DESCRIPTION

[0021] like Figures 1 to 5 As shown, an eight-speed transmission control system includes a first control oil circuit connected to a first oil chamber of control clutches K1 and K2, a second control oil circuit connected to a second oil chamber of control clutches K2 and K3, a third control oil circuit connected to a third oil chamber of control clutches K5 and K6, and a fourth control oil circuit connected to a fourth oil chamber of control clutch KF. The first control oil circuit, the second control oil circuit, the third control oil circuit and the fourth control oil circuit are arranged in parallel; the first control oil circuit, the second control oil circuit and the third control oil circuit are all provided with a proportional Valve 18 and a three-position four-way solenoid valve 19, the A and B interfaces of the three-position four-way solenoid valve 19 are respectively connected to the two ends of the corresponding oil chambers; a proportional valve 18 is arranged on the fourth control oil circuit; it also includes a balancing oil circuit for balancing the pressure difference at both ends of the first oil chamber, the second oil chamber and the third oil chamber; the balancing oil circuit is used to switch the gear to balance the pressure difference at both ends of the oil chamber, so that the piston in the oil chamber will move slowly, and then the clutch can be slowly engaged, to ensure a smooth gear shifting process, to prevent the piston from moving quickly due to excessive oil pressure difference at both ends of the oil chamber, thereby causing the problem of jitter during the speed change process.

[0022] In the present embodiment, the first control oil circuit, the second control oil circuit, the third control oil circuit, the fourth control oil circuit and the balancing oil circuit are connected to the oil tank 1 through the control main oil circuit, and the oil tank 1 is also connected to the lubrication main oil circuit, and the lubrication main oil circuit is connected to the lubrication branch oil circuit leading to each lubrication oil channel, and the lubrication main oil circuit is provided with a filter element, a one-way valve 15 and a two-position two-way solenoid valve 23, and there are two filter elements, namely a 10um filter element 10 with a filtration accuracy of 10um and a 20um filter element 9 with a filtration accuracy of 20um, and the lubrication main oil circuit is also connected to a supplementary oil circuit 17 leading to the control main oil circuit between the one-way valve and the two-position two-way solenoid valve; when it is necessary to control the action of two clutches, the control main oil circuit may have insufficient oil or insufficient oil pressure. At this time, the two-position two-way solenoid valve is actuated to cut off the oil leading to each lubrication branch oil circuit, so that the oil originally used for lubrication is supplemented to the control main oil circuit to control the action of the clutch.

[0023] In this embodiment, a proportional valve 18 and a normally closed two-position three-way solenoid valve 22 are provided in the balancing oil circuit, the 2 interface of the two-position three-way solenoid valve 22 is connected to one of the lubrication branch oil circuits, the 3 interface of the two-position three-way solenoid valve is connected to the proportional valve on the balancing oil circuit, and the 1 interface of the two-position three-way solenoid valve is respectively connected to the T interface of the three-position four-way solenoid valve on the first control oil circuit, the second control oil circuit and the third control oil circuit; the proportional valve on the control oil circuit controls the pressure at the oil inlet end of the oil chamber, while the proportional valve on the balancing oil circuit controls the pressure at the oil outlet end of the oil chamber to ensure that the oil pressure difference at both ends is not too large when the first oil chamber, the second oil chamber and the third oil chamber are actuated; at the same time, a part of the oil in the lubrication oil circuit is used to fill the control oil circuit, so that the control oil circuit is full of oil. Then, when it is necessary to control the clutch action to switch gears, it is not necessary to provide too much oil to control the main oil circuit, but only to provide the amount of oil required for the piston action, which can speed up the response speed.

[0024] In this embodiment, a filter element and a one-way valve are also provided in the control main oil circuit. There are two filter elements, namely a 10um filter element 10 with a filtration accuracy of 10um and a 20um filter element 9 with a filtration accuracy of 20um. The control main oil circuit is also connected to a pressure relief pipeline returning to the oil tank. The pressure relief pipeline has a normally closed throttle valve 11 and a relief valve 12 arranged in parallel. The pressure can be manually relieved by opening the throttle valve. When the transmission is repaired, the hydraulic system failure can be prevented to prevent incomplete pressure relief.

[0025] In this embodiment, a pressure sensor C28 and a filter are also connected to the lubrication main oil circuit. The rated pressure of the pressure sensor C28 is 8 MPa. A filter is also provided on the pipeline connecting the interface 2 of the two-position three-way solenoid valve 22 to the lubrication branch oil circuit. A metering pump 7 driven by a high-speed motor 6 is installed on the lubrication main oil circuit and the control main oil circuit. A heater 4 and an oil suction filter 5 are installed on the connecting pipeline between the oil tank 1 and the control main oil circuit and the lubrication main oil circuit. A radiator 2 is installed in the oil tank 1, and a breathable cap 3 is provided on the upper side of the oil tank.

[0026] In this embodiment, the first control oil circuit, the second control oil circuit and the third control oil circuit are equipped with filters and pressure sensors B20 on the pipelines between the three-position four-way solenoid valves and the corresponding oil chambers, and the rated pressure of the pressure sensor B is 6MPa; the fourth control oil circuit is also equipped with filters and pressure sensors B on the pipelines between the proportional valve and the fourth oil chamber.

[0027] In this embodiment, a pressure sensor C is provided on the control main oil circuit, and the rated pressure of the pressure sensor C is 8 MPa. A pressure sensor D is provided on the lubrication branch oil circuit, and the rated pressure of the pressure sensor D is 0.5 MPa.

[0028] In this embodiment, the first control oil circuit and the second control oil circuit are arranged on the transmission main valve block A, and are used to control the clutch action and lubrication in the four-speed gearbox. The third control oil circuit and the fourth control oil circuit are arranged on the transmission main valve block B, and are used to control the clutch action and lubrication in the transfer case (i.e., the two-speed case). The filter element, the one-way valve, the pressure sensor C, the throttle valve, the overflow valve and other components on the control main oil circuit are arranged on the transmission auxiliary valve block A, and the filter element, the one-way valve, the filter, the pressure sensor A and the two-position two-way solenoid valve and other components of the lubrication main oil circuit are arranged on the transmission auxiliary valve block B; one of the lubrication branch oil circuits of the lubrication main oil circuit is connected to the transmission main valve block A and then divided into multiple oil circuits for the lubrication of the four-speed case clutch, another lubrication branch oil circuit of the lubrication main oil circuit is connected to the transmission main valve block B and then divided into multiple oil circuits for the lubrication of the transfer case clutch, and the third lubrication branch oil circuit of the lubrication main oil circuit is connected to the mechanical platform valve block and then divided into multiple oil circuits for the mechanical platform lubrication.

[0029] A control method of the eight-speed transmission control system as described above comprises the following steps:

[0030] (1) In the initial state, all proportional valves and solenoid valves are de-energized;

[0031] (2) When the gear shift starts, all proportional valves are given a specified voltage, and the proportional valves of the first control oil circuit, the second control oil circuit and the third control oil circuit (i.e. Figure 1 The oil supply pressure of YA1, YA2, YA4) in the balance oil circuit is slightly greater than that of the proportional valve (i.e. Figure 1 The oil supply pressure of YA3 in the first control oil circuit, the three-position four-way solenoid valves of the first control oil circuit, the second control oil circuit and the third control oil circuit are energized respectively, and the two-position three-way solenoid valve and the two-position three-way solenoid valve are energized; at this time, the first control oil circuit, the second control oil circuit and the third control oil circuit supply oil to one end of the first oil chamber, the second oil chamber and the third oil chamber respectively, one of the clutches K1 and K2 is closed, one of the clutches K3 and K4 is closed, and one of the clutches K5 and K6 is closed; the proportional valve on the balancing oil circuit (i.e. Figure 1 YA3 in the figure supplies oil to the other end of the first oil chamber, the second oil chamber and the third oil chamber respectively through a two-position three-way solenoid valve. At the same time, the proportional valve (i.e. Figure 1 YA4 in the circuit is energized according to a predetermined curve to supply oil to the fourth oil chamber;

[0032] (3) During the clutch closing process, the controller continuously adjusts the proportional valves of the first control oil circuit, the second control oil circuit, the third control oil circuit and the balance oil circuit (i.e. Figure 1 The voltage of YA1, YA2, YA3, and YA4 in the oil chamber makes the pressure difference between the first, second, and third oil chambers larger and larger, and finally reaches a required pressure difference to make the clutch completely closed; then the proportional valve (i.e. Figure 1 The YA3 in the two-position three-way solenoid valve and the two-position three-way solenoid valve are electrically connected to complete a gear shifting process.

[0033] First gear requires clutches K1, K4, and K6 to be closed; second gear requires clutches K1, K4, and K5 to be closed; third gear requires clutches K2, K4, and K6 to be closed; fourth gear requires clutches K2, K4, and K5 to be closed; fifth gear requires clutches K1, K3, and K6 to be closed; sixth gear requires clutches K1, K3, and K5 to be closed; seventh gear requires clutches K2, K3, and K6 to be closed; eighth gear requires clutches K2, K3, and K5 to be closed; when hybrid drive is selected, both KF clutches need to be in the closed state.

[0034] Unless otherwise stated, any technical solution disclosed in the present invention disclosed above, if it discloses a numerical range, then the disclosed numerical range is a preferred numerical range, and any technician in the field should understand that the preferred numerical range is only a numerical value with a more obvious technical effect or representative value among many implementable numerical values. Since there are too many numerical values ​​to be exhaustive, the present invention discloses some numerical values ​​to illustrate the technical solution of the present invention, and the numerical values ​​listed above should not constitute a limitation on the scope of protection of the present invention.

[0035] If the present invention discloses or involves components or structures that are fixedly connected to each other, then, unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (for example, connection using bolts or screws), and can also be understood as: a non-detachable fixed connection (for example, riveting, welding). Of course, the mutual fixed connection can also be replaced by an integrated structure (for example, manufactured by integrated molding using a casting process) (except when it is obviously impossible to use an integrated molding process).

[0036] In addition, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in the present invention include states or shapes that are approximate, similar, or close to them.

[0037] Any component provided by the present invention may be assembled from a plurality of separate components, or may be a separate component manufactured by an integral forming process.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should be included in the scope of the technical solution for protection of the present invention.

Claims

1. An eight-speed transmission control system, characterized in that: It includes a first control oil circuit connected to the first oil chamber of the control clutches K1 and K2, a second control oil circuit connected to the second oil chamber of the control clutches K2 and K3, a third control oil circuit connected to the third oil chamber of the control clutches K5 and K6, and a fourth control oil circuit connected to the fourth oil chamber of the control clutch KF. The first control oil circuit, the second control oil circuit, the third control oil circuit and the fourth control oil circuit are arranged in parallel; the first control oil circuit, the second control oil circuit and the third control oil circuit are all provided with a proportional valve and a three-position four-way solenoid valve, and the A and B interfaces of the three-position four-way solenoid valve are respectively connected to the two ends of the corresponding oil chamber; the fourth control oil circuit is provided with a proportional valve; it also includes a balancing oil circuit for balancing the pressure difference at the two ends of the first oil chamber, the second oil chamber and the third oil chamber; the first control oil circuit, the second control oil circuit, the third control oil circuit and the fourth control oil circuit are arranged in parallel; The second control oil circuit, the third control oil circuit, the fourth control oil circuit and the balancing oil circuit are connected to the oil tank through the control main oil circuit, and the oil tank is also connected to the lubrication main oil circuit, and the lubrication main oil circuit is connected to the lubrication branch oil circuit leading to each lubrication oil channel, and the lubrication main oil circuit is provided with a filter element, a one-way valve and a two-position two-way solenoid valve, and the lubrication main oil circuit is also connected with a supplementary oil circuit leading to the control main oil circuit between the one-way valve and the two-position two-way solenoid valve; the balancing oil circuit is provided with a proportional valve and a normally closed two-position three-way solenoid valve, and the 2 interface of the two-position three-way solenoid valve is connected to one of the lubrication branch oil circuits, and the 3 interface of the two-position three-way solenoid valve is connected to the proportional valve on the balancing oil circuit, and the 1 interface of the two-position three-way solenoid valve is respectively connected to the T interface of the three-position four-way solenoid valve on the first control oil circuit, the second control oil circuit and the third control oil circuit.

2. The eight-speed transmission control system according to claim 1, characterized in that: The main control oil circuit is also provided with a filter element and a one-way valve; the main control oil circuit is also connected to a pressure relief pipeline returning to the oil tank, and the pressure relief pipeline is provided with a normally closed throttle valve and a relief valve arranged in parallel.

3. The eight-speed transmission control system according to claim 1, characterized in that: The lubrication main oil circuit is also connected to a pressure sensor A and a filter; the lubrication main oil circuit and the control main oil circuit are both equipped with a metering pump driven by a high-speed motor, a heater and an oil suction filter are installed on the connecting pipelines between the oil tank and the control main oil circuit and the lubrication main oil circuit, a radiator is installed in the oil tank, and a breathable cap is provided on the upper side of the oil tank.

4. The eight-speed transmission control system according to claim 1, characterized in that: The first control oil circuit, the second control oil circuit and the third control oil circuit are equipped with filters and pressure sensors B on the pipelines between the three-position four-way solenoid valves and the corresponding oil chambers; the fourth control oil circuit is also equipped with filters and pressure sensors B on the pipelines between the proportional valves and the fourth oil chambers.

5. A control method for an eight-speed transmission control system as claimed in claim 1, characterized in that: The following steps are involved: (1) In the initial state, all proportional valves and solenoid valves are de-energized; (2) At the start of shifting, all proportional valves are given a specified voltage, and the oil supply pressure of the proportional valves in the first control oil circuit, the second control oil circuit and the third control oil circuit is slightly greater than the oil supply pressure of the proportional valves in the balancing oil circuit. The three-position four-way solenoid valves in the first control oil circuit, the second control oil circuit and the third control oil circuit are energized respectively, and the two-position three-way solenoid valves and the two-position three-way solenoid valves are energized respectively; at this time, the first control oil circuit, the second control oil circuit and the third control oil circuit supply oil to one end of the first oil chamber, the second oil chamber and the third oil chamber respectively, and one of the clutches K1 and K2 is closed, one of the clutches K3 and K4 is closed, and one of the clutches K5 and K6 is closed; The proportional valve on the balancing oil circuit supplies oil to the other end of the first oil chamber, the second oil chamber and the third oil chamber respectively through the two-position three-way solenoid valve. At the same time, the proportional valve on the fourth control oil circuit is energized according to a predetermined curve to supply oil to the fourth oil chamber; (3) During the closing process of the clutch, the voltage of the proportional valves of the first control oil circuit, the second control oil circuit, the third control oil circuit and the balancing oil circuit is continuously adjusted to increase the pressure difference between the two ends of the first, second and third oil chambers, and finally reach a required pressure difference to fully close the clutch; then the proportional valve on the balancing oil circuit, the two-position three-way solenoid valve and the two-position three-way solenoid valve are energized to complete a shifting process.

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