Clutch exhaust pressure release control method, control device, and vehicle

Abstract

The application provides a clutch exhaust pressure relief control method and device and a vehicle. The clutch exhaust pressure relief control method comprises the following steps: obtaining the rotating speed of an engine after the vehicle is powered on; and when the rotating speed of the engine is greater than a preset rotating speed threshold, controlling an electronic pump to rotate forward at a first preset pressure for a first preset time, wherein the first preset pressure is lower than a first preset pressure threshold. According to the clutch exhaust pressure relief control method, when the rotating speed of the engine is greater than the preset rotating speed threshold after the vehicle is powered on, the electronic pump is controlled to rotate forward at the first preset pressure which is lower than the first preset pressure threshold for the first preset time, so that the oil circuit is filled with oil, and the influence of air on pressure stability when the oil circuit is occasionally filled with air is reduced. Without changing the existing structure of the clutch device, the cost is low, the exhaust effect is good, and the driving experience of the driver is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field, in particular to a clutch exhaust pressure relief control method. BACKGROUND

[0002] The clutch operating system triggers the clutch master pump by stepping on the clutch pedal, first converts mechanical energy into hydraulic pressure, and then the hydraulic pressure acts on the clutch slave pump through the pipeline, so that the hydraulic pressure is converted into mechanical energy, so that the separating bearing acts on the separation finger of the clutch pressure plate, and the separation and combination of the clutch are realized.

[0003] Under normal working conditions of the clutch, the clutch pipeline is full of oil. If there is gas in the clutch pipeline, it will reduce the efficiency of the clutch system, so it is necessary to exhaust the clutch pipeline. If the exhaust effect is not good, the pressure in the clutch cavity will be unstable, and other faults will occur. Therefore, the exhaust effect of the clutch system plays a key role in the separation and combination of the clutch, and further affects the whole vehicle.

[0004] The existing clutch operating system usually has the following exhaust methods:

[0005] 1. By means of a pressure container, the hydraulic oil in the pressure container is injected into the clutch slave pump, the hydraulic oil and gas in the clutch slave pump enter the clutch master pump, the hydraulic oil and gas in the clutch master pump backflow to the oil storage tank, and the gas outlet at the top of the oil storage tank exhausts the gas.

[0006] 2. Set up a booster pump, use reverse pressure to inject brake fluid, under the action of the delivery pressure of the brake fluid, all the air in the clutch slave pump, clutch master pump and hydraulic pipeline is exhausted into the oil storage pot, and the clutch exhaust work is quickly completed.

[0007] 3. Add a compensation tank and an electric oil pump, use the liquid in the compensation tank to form pressure on the gas in the liquid tank, master pump, slave pump and pipeline by the electric oil pump, force the air into the compensation tank, and then exhaust the air.

[0008] The above exhaust methods all need to improve the clutch operating system, or the exhaust method depends on the new equipment, which leads to a relatively complex structure of the clutch operating system and high cost. SUMMARY

[0009] Therefore, the present application aims to provide a clutch exhaust pressure relief control method to better achieve the exhaust effect and reduce the cost.

[0010] To achieve the above purpose, the technical scheme of the present application is as follows:

[0011] A clutch exhaust pressure relief control method, comprising:

[0012] After the vehicle is powered on, the engine speed is acquired;

[0013] When the engine speed is greater than a preset speed threshold, a clutch exhaust method is executed, the exhaust method comprising controlling the electronic pump to rotate forward at a first preset pressure for a first preset time, the first preset pressure being lower than a first preset pressure threshold.

[0014] Further, the first preset pressure threshold is a clutch half-engage point pressure value.

[0015] Further, when the first preset time is greater than a first preset time threshold, or the actual pressure in the clutch actuation chamber is not lower than the first preset pressure threshold, the electronic pump is controlled to act according to the clutch request torque information.

[0016] Further, when the engine speed is not less than an idle speed and the clutch request torque changes from positive to negative, a clutch pressure relief method is executed, the clutch pressure relief method comprising controlling the electronic pump to rotate reverse at a second preset pressure for a second preset time.

[0017] Further, when the second preset time is greater than a second preset time threshold, or the actual pressure in the clutch actuation chamber is lower than a second preset pressure threshold, or the clutch request torque changes from negative to positive, the electronic pump is controlled to act according to the clutch request torque information.

[0018] Compared with the prior art, the present application has the following advantages:

[0019] The clutch exhaust pressure relief control method of the present application can make the oil circuit full of oil when the vehicle is powered on and the engine speed is greater than a preset speed threshold, and then reduce the influence of air entering the oil circuit on pressure stability, without changing the existing structure of the clutch device, at a low cost, to achieve good exhaust effect and improve the driving experience of the driver.

[0020] Another object of the present application is to provide a clutch exhaust pressure relief control device, comprising an acquisition unit and a control unit connected with the acquisition unit.

[0021] The acquisition unit is used to acquire the engine speed after the vehicle is powered on.

[0022] The control unit is used to execute a clutch exhaust method when the engine speed is greater than a preset speed threshold, the exhaust method comprising controlling the electronic pump to rotate forward at a first preset pressure for a first preset time, the first preset pressure being lower than a first preset pressure threshold.

[0023] Further, the control unit is further configured to control the electronic pump to act according to the clutch request torque information when the first preset time is greater than a first preset time threshold, or when the actual pressure in the clutch actuating cavity is not lower than a first preset pressure threshold.

[0024] Further, the control unit is further configured to execute a clutch pressure relief method when the engine speed is not less than an idle speed and the clutch request torque changes from a positive value to a negative value, the clutch pressure relief method comprising controlling the electronic pump to reverse at a second preset pressure for a second preset time.

[0025] Further, the control unit is further configured to control the electronic pump to act according to the clutch request torque information when the second preset time is greater than a second preset time threshold, or when the actual pressure in the clutch actuating cavity is lower than a second preset pressure threshold, or when the clutch request torque changes from a negative value to a positive value.

[0026] Meanwhile, the present application also relates to a vehicle provided with the clutch pressure relief control device as described above.

[0027] The vehicle and the clutch pressure relief control device of the present application have the same beneficial effects as the clutch exhaust pressure relief control method described above, and thus repeated descriptions are omitted. BRIEF DESCRIPTION OF DRAWINGS

[0028] The accompanying drawings, which form a part of the present application, are intended to provide further understanding of the present application and are incorporated herein for a purpose of explanations. The illustrative embodiments of the present application, together with its description, are employed to explain the application and do not constitute any improper limitation to the application. In the drawings:

[0029] Figure 1 A flowchart of the clutch exhaust pressure relief control method according to an embodiment of the present application;

[0030] Figure 2 Another flowchart of the clutch exhaust pressure relief control method according to an embodiment of the present application;

[0031] Figure 3 A principle block diagram of the clutch exhaust pressure relief control device according to an embodiment of the present application;

[0032] Figure 4 A structure diagram of the clutch control system according to an embodiment of the present application.

[0033] Explanation of reference signs:

[0034] 1, acquisition unit; 2, control unit; 3, torque calculation unit; 4, pressure sensor; 5, clutch oil pump; 501, execution cavity; 6, oil circuit; 7, throttle hole; 8, oil groove; 9, electronic pump; 10, filter; 11, oil pan. DETAILED DESCRIPTION

[0035] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0036] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "back" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0037] In addition, in the description of the present application, unless otherwise explicitly limited, the terms "mounting", "connecting", "connection", "connector" should be broadly understood. For example, it can be fixedly connected, or it can be detachably connected, or it can be integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood in combination with the specific circumstances.

[0038] The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0039] The present embodiment relates to a clutch exhaust pressure relief control method, which is suitable for a clutch operating system using an electronic pump to charge oil. Without changing the existing hardware design of the clutch operating system, the method quickly discharges the gas mixed in the clutch operating system through a strategy, thereby improving the pressure stability of the clutch.

[0040] Based on the above design idea, an exemplary flowchart of the clutch exhaust pressure relief control method of the present embodiment is shown in Figure 1 which mainly includes the following steps.

[0041] S101, after the vehicle is powered on, the speed of the engine is acquired.

[0042] S102, when the speed of the engine is greater than a preset speed threshold, a clutch exhaust method is executed, and the exhaust method includes controlling the electronic pump 9 to rotate in a positive direction at a first preset pressure for a first preset time, and the first preset pressure is lower than a first preset pressure threshold.

[0043] In order to better understand the clutch exhaust pressure relief control method of the embodiment, next first refer to Figure 4 Briefly describe the structure of the clutch operating system. When the electronic pump 9 is working, the electronic pump 9 will suck oil from the oil pan 11, send it to the clutch oil pump 5 through the oil path 6, and specifically to the execution chamber 501 of the oil cylinder. The part of the oil will be filtered by the filter 10 before entering the electronic pump 9 to filter out the impurities in the oil. When the pressure in the oil path 6 is high, part of the oil will be discharged to the oil tank 8 through the throttle hole 7.

[0044] When the vehicle is parked for a long time or the vehicle body is tilted during driving or the oil is deteriorated and mixed with air, it is possible to cause air to be sucked into the clutch execution chamber 501 when the electronic pump 9 sucks oil. If this part of the air cannot be discharged in time before the driver drives, and is discharged through the throttle hole 7 during clutch operation, it will cause the actual pressure in the clutch execution chamber 501 to change suddenly, thereby causing the actual transmission torque of the clutch to change, which will bring negative driving experience to the driver.

[0045] Next, refer to the clutch exhaust pressure relief control method of the embodiment. The control method mainly includes the following steps. Figure 2

[0046] S101, after the vehicle is powered on, the engine speed is obtained.

[0047] In this step, the engine speed is obtained after the vehicle is powered on, which is a necessary condition for executing the following clutch exhaust method. The main reason is that the clutch may be occasionally filled with air when the vehicle is started.

[0048] The judgment condition of the vehicle power-on can use the existing relay on the vehicle, such as K15 relay. The relay can be connected with the control unit 2 described below. The engagement and disengagement states of the relay are used to judge whether the vehicle is powered on or not. For example, the previous time is 0 and the current time is not 0. It can be judged whether the driver has the intention to drive the vehicle or not. The clutch is effectively exhausted in time when the driver has the intention to drive the vehicle.

[0049] In addition, in this step, the engine speed is obtained, which is to determine whether the engine is fired in the following step, because the exhaust is triggered when the engine is fired, which is beneficial to cover the noise of the electronic pump 9.

[0050] S102, when the engine speed is greater than a preset speed threshold, execute the clutch exhaust method, which includes controlling the electronic pump 9 to rotate at a first preset pressure for a first preset time, and recording the rotation time, which includes the time when the clutch pressure is maintained within a certain range. The preset speed threshold may be 50 rpm, for example. ​

[0051] Here, the first preset pressure is lower than a first preset pressure threshold, and the first preset pressure threshold is a clutch half-engagement point pressure value Kp. In this step, the first preset pressure is a positive pressure, for example, 2 Bar, which can prevent the driver from perceiving vehicle shaking, so as to improve the operation comfort.

[0052] In this step, whether the engine speed is greater than a preset speed threshold can be used to determine whether the engine is fired, and the electronic pump 9 is controlled to rotate forward at the first preset pressure for the first preset time, so as to quickly empty the air in the oil circuit 6 and the clutch actuating cavity 501, so that the oil circuit 6 is filled with oil, thereby reducing the influence of the air occasionally entering the oil circuit 6 on the clutch pressure stability.

[0053] In addition, the first preset pressure is lower than the first preset pressure threshold during exhaust, that is, the pressure in the clutch actuating cavity 501 is kept below the first preset pressure threshold during the exhaust of the clutch by the forward rotation of the electronic pump 9, so as to avoid affecting the normal shift fork gear engagement.

[0054] S103, when the first preset time is greater than a first preset time threshold, or the actual pressure in the clutch actuating cavity 501 is not lower than the first preset pressure threshold, the electronic pump 9 is controlled to act according to the clutch request torque information, and the clutch exhaust method is recorded.

[0055] In this step, the first preset time threshold can be 150 ms, and the first preset pressure threshold can be the clutch half-engagement point pressure value Kp. Here, the first preset pressure threshold is set to the clutch half-engagement point pressure value Kp, because if the actual pressure of the clutch exceeds the clutch half-engagement point pressure value Kp, the shift fork gear engagement will be hindered.

[0056] In addition, the electronic pump 9 is controlled to act according to the clutch request torque information, which is to exit the clutch exhaust method and respond to the normal demand of the driver.

[0057] It should be noted here that if the clutch exhaust method has been executed in the current driving cycle, the clutch exhaust method will not be executed in the driving cycle. Because after the exhaust is completed, the oil circuit 6 will be filled with oil, and the exhaust is performed only once in a single driving cycle, so as to reduce the excessive intervention of the exhaust strategy on the clutch oil pump 5.

[0058] S104, when the engine speed is not less than the idle speed and the clutch request torque changes from positive to negative, the clutch pressure relief method is executed, which includes controlling the electronic pump 9 to reverse at a second preset pressure for a second preset time, and recording the reversing time. After the engine is fired, when the clutch request torque changes from positive to negative, the electronic pump 9 is reversed to quickly realize the clutch pressure relief, so as to reduce the influence of torque hysteresis.

[0059] In the existing clutch operating system, the oil leakage of the clutch is generally realized by the reaction force of the return spring of the clutch. If the oil leakage of the clutch is realized by the reaction force of the return spring during the driving of the vehicle, the oil leakage is slow, especially when the target pressure is lower than the clutch half-combination point pressure, the oil leakage is slower. Although increasing the diameter of the oil leakage hole is beneficial to the oil leakage, it will increase the power requirement of the electronic pump 9, causing design waste. Therefore, in the embodiment, the method of step S104 is adopted to release the pressure of the clutch.

[0060] It should be noted that when the clutch request torque changes from a negative value to a positive value, for example, at the end of the double clutch request torque interaction stage, the clutch request torque will change from positive to negative, indicating that the clutch has a pressure release requirement. The idle speed of the engine may be, for example, 800 rpm. The second preset pressure is a negative pressure, which may be, for example, -2 Bar, to reverse the electronic pump 9 to achieve rapid pressure release.

[0061] S105, when the second preset time is greater than the second preset time threshold, or the actual pressure in the clutch actuating chamber 501 is lower than the second preset pressure threshold, or the clutch request torque changes from a negative value to a positive value, the electronic pump 9 is controlled according to the clutch request torque information. When the actual pressure is lower than the limit value, or the reverse time is too long, stop reversing to prevent excessive reversal of the oil circuit 6, but still ensure that the oil circuit 6 is full of oil.

[0062] In this step, the second preset time threshold may be, for example, 200 ms, and the second preset pressure threshold may be, for example, Kp-500 mBar. When the clutch request torque changes from a negative value to a positive value, it indicates that the clutch has a torque transmission requirement again. In addition, the electronic pump 9 is controlled according to the clutch request torque information, which is equivalent to stopping the pressure release of the clutch, i.e. deactivating the reverse strategy, to respond to normal requirements.

[0063] The clutch exhaust pressure release control method of the embodiment can automatically identify the working condition to achieve rapid pressure release. After the vehicle is powered on, when the engine speed is greater than the preset speed threshold, the electronic pump 9 is controlled to rotate forward at a first preset pressure lower than the first preset pressure threshold for a first preset time. The first preset pressure is lower than the first preset pressure threshold, without the need to change the existing structure of the clutch device, the cost is lower, and better exhaust effect can be achieved.

[0064] It should be noted that the clutch exhaust pressure release control method of the embodiment is not only suitable for single clutches, but also suitable for existing double clutches. Since the double clutch has two actuating chambers, only one actuating chamber needs to be exhausted after the engine is ignited, and the first working actuating chamber can be exhausted.

[0065] Meanwhile, the embodiment also relates to a clutch exhaust pressure release control device, like Figure 3As shown, it mainly comprises an acquisition unit 1, and a control unit 2 connected with the acquisition unit 1.

[0066] The acquisition unit 1 is configured to acquire the engine speed after the vehicle is powered on. The acquisition unit 1 may, for example, be an existing speed sensor, which can transmit the engine speed information to the control unit 2.

[0067] The control unit 2 may, for example, be an existing controller on the vehicle, such as an ECU, which is electrically connected with the electronic pump 9, and is configured to execute the clutch exhaust method when the engine speed is greater than a preset speed threshold. The exhaust method comprises controlling the electronic pump 9 to rotate forward at a first preset pressure for a first preset time, and the first preset pressure is lower than a first preset pressure threshold.

[0068] As a preferred implementation, the control unit 2 is further configured to control the electronic pump 9 to act according to the requested torque information of the clutch when the first preset time is greater than a first preset time threshold, or the actual pressure in the clutch actuating cavity 501 is not lower than the first preset pressure threshold. The pressure in the clutch actuating cavity 501 can be obtained by an existing pressure sensor 4 connected with the control unit 2, and the pressure sensor 4 can transmit the actual pressure information in the clutch actuating cavity 501 to the control unit 2.

[0069] As a preferred implementation, the control unit 2 is further configured to execute the clutch pressure relief method when the engine speed is not less than an idle speed, and the requested torque of the clutch changes from a positive value to a negative value. The clutch pressure relief method comprises controlling the electronic pump 9 to rotate reversely at a second preset pressure for a second preset time.

[0070] As a preferred implementation, the control unit 2 is further configured to control the electronic pump 9 to act according to the requested torque information of the clutch when the second preset time is greater than a second preset time threshold, or the actual pressure in the clutch actuating cavity 501 is lower than a second preset pressure threshold, or the requested torque of the clutch changes from a negative value to a positive value. The requested torque of the clutch can be obtained by an existing torque calculation unit 3 connected with the control unit 2, and the torque calculation unit 3 can transmit the requested torque information of the clutch to the control unit 2, and the control unit 2 controls the electronic pump 9 to act according to the requested torque information of the clutch.

[0071] The clutch pressure relief control device of the present embodiment has the same beneficial effects as the clutch exhaust pressure relief control method described above, and will not be described here.

[0072] Meanwhile, the present embodiment also relates to a vehicle provided with the clutch pressure relief control device described above. The vehicle of the present embodiment, by applying the clutch pressure relief control device described above, is conducive to reducing the cost of the vehicle and reducing the negative feelings of the driver caused by the air in the clutch.

[0073] The above merely provides the preferred embodiment of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall fall into the protection scope of the present application.

Claims

1. A clutch vent pressure relief control method characterized by, Comprising: After the vehicle is powered on, the engine speed is obtained; When the engine speed is greater than a preset speed threshold, a clutch exhaust method is executed, the clutch exhaust method comprising controlling the electronic pump (9) to rotate forward at a first preset pressure for a first preset time, the first preset pressure being lower than a first preset pressure threshold; When the engine speed is not less than an idle speed and the clutch request torque changes from a positive value to a negative value, a clutch pressure relief method is executed, the clutch pressure relief method comprising controlling the electronic pump (9) to rotate reverse at a second preset pressure for a second preset time.

2. The clutch exhaust pressure relief control method according to claim 1, wherein: The first preset pressure threshold is a clutch half-connection point pressure value.

3. The clutch exhaust pressure relief control method according to claim 1, wherein: When the first preset time is greater than a first preset time threshold, or the actual pressure in the actuator chamber (501) of the clutch is not lower than the first preset pressure threshold, the electronic pump (9) is controlled to act according to the clutch request torque information.

4. The clutch exhaust pressure relief control method according to claim 1, wherein: When the second preset time is greater than a second preset time threshold, or the actual pressure in the actuator chamber (501) of the clutch is lower than a second preset pressure threshold, or the clutch request torque changes from a negative value to a positive value, the electronic pump (9) is controlled to act according to the clutch request torque information.

5. A clutch exhaust pressure relief control device, comprising: An acquisition unit (1), and a control unit (2) connected with the acquisition unit (1); The acquisition unit (1) is used to obtain the engine speed after the vehicle is powered on; The control unit (2) is used to execute a clutch exhaust method when the engine speed is greater than a preset speed threshold, the exhaust method comprising controlling the electronic pump (9) to rotate forward at a first preset pressure for a first preset time, the first preset pressure being lower than a first preset pressure threshold; The control unit (2) is also used to execute a clutch pressure relief method when the engine speed is not less than an idle speed and the clutch request torque changes from a positive value to a negative value, the clutch pressure relief method comprising controlling the electronic pump (9) to rotate reverse at a second preset pressure for a second preset time.

6. The clutch exhaust pressure relief control device according to claim 5, wherein: The control unit (2) is also used to control the electronic pump (9) to act according to the clutch request torque information when the first preset time is greater than a first preset time threshold, or the actual pressure in the actuator chamber (501) of the clutch is not lower than the first preset pressure threshold.

7. The clutch exhaust pressure relief control device according to claim 5, wherein: The control unit (2) is also used to control the electronic pump (9) to act according to the clutch request torque information when the second preset time is greater than a second preset time threshold, or the actual pressure in the actuator chamber (501) of the clutch is lower than a second preset pressure threshold, or the clutch request torque changes from a negative value to a positive value.

8. A vehicle characterized by comprising: The vehicle is provided with the clutch pressure relief control device according to any one of claims 5 to 7.

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