JP4661057B2 - Automatic clutch control device - Google Patents

Description

  The present invention relates to an automatic clutch control device for connecting and disconnecting a clutch using hydraulic pressure, and in particular, an automatic clutch control device capable of appropriately performing subsequent clutch connection control when the clutch is disconnected. It is about.

  2. Description of the Related Art Conventionally, an automatic clutch control device that automatically connects and disconnects a clutch of a vehicle or the like using hydraulic pressure is known (see, for example, Patent Documents 1 and 2).

  The automatic clutch control device usually includes an oil pump connected to the crankshaft of the engine, and connects and disconnects the clutch by switching a valve for guiding the oil pressurized by the oil pump to the operating mechanism of the clutch.

  Some of these automatic clutch control devices strictly control the clutch engagement operation in order to eliminate the shock at the time of clutch engagement and reduce the time required for the connection. For example, there is one that operates in the contact direction relatively abruptly before the point (torque point) before the torque on the input side of the clutch starts to be transmitted to the output side, and then gradually connects. Such clutch engagement control is executed according to a program set and stored in advance.

JP 2001-30801 A JP 2002-295529 A

  However, in such a conventional automatic clutch control device, when the clutch is disengaged for a long time, the connection feeling may be deteriorated when the clutch is subsequently engaged.

  As a result of conducting various tests to find the cause of this phenomenon, the present applicant has found the following two causes.

  1) Since oil is not supplied into the hydraulic circuit that operates the clutch while the clutch is disengaged, if the clutch is disengaged for a long period of time, the oil that has been filled in the hydraulic circuit will open a fine gap such as a valve. The oil amount is reduced by passing through. In addition, air may enter the hydraulic circuit. However, the clutch engagement control program described above is created on the assumption that the hydraulic circuit is sufficiently filled with oil, so if the clutch is connected with the oil amount in the hydraulic circuit lowered, the control program There is a mismatch between the actual oil amount and the connection feeling is deteriorated.

  2) Since the characteristics (viscosity, etc.) of the clutch hydraulic oil change according to the oil temperature, it is common to correct the above-described clutch contact control program according to the oil temperature. Normally, a temperature sensor is provided in the oil pan, and the program is corrected based on the detection value of this sensor. However, when the clutch is disengaged, there is no oil flow in the state where the hydraulic circuit that operates the clutch and the oil pan are shut off, so if this state continues for a long period of time, the oil temperature in the oil pan and the hydraulic circuit There is a difference in the oil temperature inside. If the clutch is connected in this state, the control program is corrected based on the oil temperature of the oil pan, so that a mismatch occurs between the control program and the actual clutch operating oil temperature, and the connection feeling deteriorates.

  The present invention was devised in view of these problems, and its purpose is to enable appropriate clutch engagement control to be performed thereafter when the clutch is disengaged continuously. It is in.

In order to achieve the above-mentioned object, the present invention connects / disconnects a clutch using hydraulic pressure, and when the gear position of the transmission is a parking or neutral position, clutch control means for disengaging the clutch, A period measuring means for measuring a period during which the gear position of the machine is the parking position or the neutral position; and a hydraulic circuit for supplying oil maintained at a predetermined oil pressure to the clutch. When it is disconnected, the supply of oil from the hydraulic circuit to the clutch is shut off, and when the clutch is in contact, oil is supplied from the hydraulic circuit to the clutch, and is continued by the period measuring means. when the period of time that is measured Te becomes the first setting period, the instantaneous engagement control for operating the clutch only contact direction second setting period Even without those to run more than once.

Here, oil temperature measuring means for measuring the temperature of the oil in the oil pan is further provided, and the clutch control means is configured to perform the instant even when the temperature measured by the oil temperature measuring means is equal to or lower than a set temperature. The contact control may be executed at least once.

  The instantaneous contact control may operate the clutch in the contact direction for a period shorter than a period necessary for the clutch to be completely connected.

  According to the present invention, when the state in which the clutch is disengaged continues for a predetermined period, the oil on the oil pan side is supplied into the hydraulic circuit that operates the clutch by instantaneous contact control. Therefore, the hydraulic circuit is sufficiently filled with oil, the difference between the oil temperature in the hydraulic circuit and the oil temperature in the oil pan is reduced, and the subsequent clutch engagement control can be appropriately performed.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  First, an outline of a vehicle power transmission device to which the automatic clutch control device of this embodiment is applied will be described with reference to FIG.

  As shown in the figure, the power transmission device includes a fluid coupling 2 (here, a torque converter) connected to the crankshaft 1 of the engine E, and a speed change clutch 3 (here, a wet type clutch) connected to the output shaft of the fluid coupling 2. Plate clutch) and a transmission T / M (here, a manual two-shaft transmission) coupled to the output shaft of the transmission clutch 3.

  The fluid coupling 2 includes a lockup clutch 5 for integrally connecting the input side and the output side of the fluid coupling 2.

  The lock-up clutch 5 and the transmission clutch 3 are operated by hydraulic pressure, and the automatic clutch control device automatically connects and disconnects the clutches 5 and 3 by switching the supply and discharge of oil to and from the clutches 5 and 3. 6 is provided. The hydraulic circuit for operating these clutches 5 and 3 will be described in detail later.

  Detection values of sensors provided in each part of the power transmission device are input to the control device 6, and the control device 6 controls connection / disconnection of the lockup clutch 5 and the transmission clutch 3 based on the detection values of these sensors.

  As various sensors, an engine rotation sensor 7 that detects the rotation speed of the crankshaft 1 of the engine E, a turbine rotation sensor 9 that detects the rotation speed of the input shaft of the transmission clutch 3 (the output shaft of the fluid coupling 2), and the transmission clutch 3 T / M rotation sensor 10 for detecting the rotation speed of the output shaft (input shaft of the transmission T / M), the vehicle speed sensor 11 for detecting the rotation speed of the output shaft of the transmission T / M, and the depression amount of the accelerator pedal 12 An accelerator opening sensor 13 for detecting the brake pedal, a brake pedal sensor 16 for detecting the depression amount of the brake pedal 15, a shift lever sensor 19 for detecting the operation of the shift lever 17 by the driver, and a gear for detecting the gear position of the transmission T / M. There is a position sensor 20 or the like.

  In this power transmission device, when the vehicle starts, the shift clutch 3 is engaged and the lockup clutch 5 is disconnected, and the vehicle starts with the creep force of the fluid coupling 2. Then, after the vehicle has started, the lockup clutch 5 is connected, and after that, when the shift operation of the driver is detected by the shift lever sensor 19, the transmission clutch 3 is connected and disconnected to allow the transmission operation of the transmission T / M. To do. Further, if the vehicle speed is reduced to a certain level when the vehicle is about to stop, the lock-up clutch 5 is disconnected to prevent engine stall. That is, in this power transmission device, the lock-up clutch 5 is used to allow the vehicle to start and stop, and the transmission clutch 3 is used to allow the transmission T / M to shift.

  A hydraulic circuit that operates the lock-up clutch 5 and the shift clutch 3 will be described with reference to FIG.

  As shown in the figure, the hydraulic circuit includes a supply line 46 that is connected to an oil pan 45 and includes a filter F and an oil pump OP. The oil pump OP is connected to the crankshaft 1 (see FIG. 1) of the engine E. When the engine E is driven, the oil in the oil pan 45 is supplied to the supply line 46. The oil pressure in the supply line 46 is maintained at a preset pressure by the relief valve 47.

  A lockup clutch control valve 49 is connected to the supply line 46 via a line 48. The lockup clutch control valve 49 can connect and disconnect the lockup clutch 5 by switching the direction of the pressure oil flowing to the fluid coupling 2 (lockup clutch 5). The lockup clutch control valve 49 is connected to oil return lines 50 and 60 for returning the pressure oil that has passed through the lockup clutch 5 to the oil pan 45. The oil return line 50 is provided with a throttle valve 51, a cooler 52, a relief valve 53, and the like.

  The lockup clutch control valve 49 is switched by an electromagnetic valve 56 provided on a signal line 55 connected to the supply line 46.

  That is, when the solenoid valve 56 is closed, the lock-up clutch control valve 49 is in the state shown in the figure, and the pressure oil from the line 48 flows to the oil discharge line 36, the lock-up clutch 5, and the oil supply line 37. Return to the oil pan 45 from the return line 50. At this time, the pressure oil flowing in the lock-up clutch 5 operates the lock-up clutch 5 in the disconnecting direction.

  On the other hand, when the electromagnetic valve 56 is opened by the control device 6, the set pressure oil is supplied from the signal line 55 to the lockup clutch control valve 49, and the lockup clutch control valve 49 is switched. Then, the pressure oil from the line 48 flows in the opposite direction to the oil supply line 37, the lockup clutch 5 and the oil discharge line 36, and returns to the oil pan 45 from the oil return line 60. In this case, the pressure oil flowing in the lockup clutch 5 operates the lockup clutch 5 in the contact direction.

  In this way, the lockup clutch 5 is connected / disconnected by controlling the opening / closing of the electromagnetic valve 56 by the control device 6.

  Further, a shift clutch control valve 61 is connected to the supply line 46 via a line 68. The transmission clutch 3 can be connected / disconnected by switching the supply / discharge of oil to / from the operating mechanism 30 of the transmission clutch 3 by the transmission clutch control valve 61.

  The shift clutch control valve 61 is switched by an electromagnetic valve 63 provided on a signal line 62 connected to the supply line 46.

  That is, as shown in the figure, when the electromagnetic valve 63 is opened by the control device 6, the set pressure pressure oil is supplied from the signal line 62 to the transmission clutch control valve 61, and the transmission clutch control valve 61 is closed. Accordingly, no pressure oil is supplied to the operating mechanism 30, and the transmission clutch 3 is operated to the disconnected side by the urging force of the spring 42 of the operating mechanism 30.

  On the other hand, when the electromagnetic valve 63 is closed, the shift clutch control valve 61 is switched to open. As a result, the pressure oil is supplied to the operating mechanism 30 through the oil supply line 69, the piston 43 of the operating mechanism 30 is moved against the urging force of the spring 42, and the transmission clutch 3 is operated to the contact side.

  Thus, the transmission clutch 3 is connected / disconnected by controlling the opening / closing of the electromagnetic valve 63 by the control device 6. The “clutch control means” in the “Claims” comprehensively includes mechanisms necessary for connecting and disconnecting the transmission clutch 3, such as the operating mechanism 30, the transmission clutch control valve 61, the electromagnetic valve 63, and the control device 6. It is called.

  In the present embodiment, the control device 6 detects when the gear position of the transmission T / M detected by the gear position sensor 20 in FIG. 1 is a gear position other than the traveling gear stage, that is, the gear position is the parking position ( In the case of P) or the neutral position (N), the transmission clutch 3 is basically disengaged. This is because the shift clutch 3 is disengaged to reduce the load on the starter motor when the engine is started, and to reduce the engine load when the engine is operating, thereby improving fuel efficiency.

  Further, when the transmission clutch 3 is connected, the control device 6 executes predetermined predetermined clutch engagement control. In the present embodiment, the transmission clutch 3 is operated in the contact direction relatively abruptly until a point (torque point) at which the torque of the input shaft of the transmission clutch 3 starts to be transmitted to the output shaft, and then gradually connected. According to this, it is possible to shorten the clutch connection time and reduce the connection shock. The contents of this clutch engagement control are set and stored in advance in the control device 6 as a control program for the amount of current supplied to the electromagnetic valve 63, and the control device 6 connects the transmission clutch 3 according to the program.

  Here, the operating oil used for connecting / disconnecting the speed change clutch 3 changes in characteristics (viscosity, etc.) according to the oil temperature. Therefore, in order to prevent variation or deterioration of the clutch connection feeling due to the difference in oil temperature, the above-described clutch connection control program is corrected based on the oil temperature. More specifically, the current oil temperature is measured by a temperature sensor 40 (oil temperature measuring means) provided in the oil pan 45, and the contact control program for the transmission clutch 3 is corrected based on the measured value.

  In this automatic clutch control device, when the state where the transmission clutch 3 is disengaged (that is, the state where the gear position of the transmission T / M is the parking or neutral position) continues for a predetermined period, It is devised so that control can be performed appropriately. This will be described below.

  First, when the state in which the transmission clutch 3 is disconnected continues, two reasons why the connection feeling when the transmission clutch 3 is connected will be described with reference to FIG.

  1) When the transmission clutch 3 is disconnected, the solenoid valve 63 is opened and the transmission clutch control valve 61 is closed, so that oil is not supplied into the oil supply line 69. If this state continues for a long period of time, the oil in the oil supply line 69 (hydraulic circuit) escapes through a minute gap, so that the amount of oil in the oil supply line 69 decreases or air enters the oil supply line 69. There is. However, since the clutch engagement control program described above is created on the assumption that the oil supply line 69 is sufficiently filled with oil, if the shift clutch 3 is connected in this state, the control program, the actual oil amount, A mismatch occurs and the connection feeling deteriorates.

  2) When the transmission clutch 3 is disengaged (when the transmission clutch control valve 61 is closed), the oil supply line 69 and the hydraulic circuit on the oil pan 45 side are shut off, and the oil flow between them Since no change (exchange) is performed, if this state lasts for a long period of time, the temperature of the oil in the oil pan 45 detected by the temperature sensor 40 and the oil in the oil supply line 69 that actually operates the transmission clutch 3 are detected. There is a difference in temperature. When the speed change clutch 3 is connected in this state, the control program is corrected based on the oil temperature of the oil pan 45, so that a mismatch occurs between the control program and the actual hydraulic oil temperature, and the connection feeling deteriorates.

  Therefore, the automatic clutch control device according to the present embodiment is devised as follows in order to prevent the deterioration of the connection feeling due to these reasons.

  That is, when the gear position of the transmission T / M is in the parking or neutral position for a predetermined first setting period or more, the instantaneous contact control is performed so that the transmission clutch 3 is operated in the contact direction only for the predetermined second setting period. At least once.

  According to this, the solenoid valve 63 is temporarily closed and the shift clutch control valve 61 is temporarily opened, so that oil on the oil pan 45 side is supplied into the oil supply line 69. As a result, the oil supply line 69 is sufficiently filled with oil, and the difference between the oil temperature in the oil supply line 69 and the oil temperature in the oil pan 45 is reduced. Therefore, even if the shift clutch 3 is subsequently connected according to the control program corrected based on the measured value of the temperature sensor 40, the connection feeling can be appropriately connected without deteriorating.

  In this embodiment, the gear position sensor 20 shown in FIG. 1 and a timer built in the control device 6 are used as the period measuring means for measuring the period in which the gear position of the transmission T / M is a parking or neutral position. Yes. That is, when the gear position sensor 20 detects that the transmission T / M is parked or geared into the neutral position, a timer is started and its duration is measured.

  If the measured value of the timer is equal to or longer than a predetermined first set period, the control device 6 temporarily sets the electromagnetic valve 63 regardless of whether the gear position of the transmission T / M is a parking position or a neutral position. Closed. As a result, the transmission clutch control valve 61 is switched to open, and the oil on the oil pan 45 side is filled into the oil supply line 69 through the line 68. If the control device 6 closes the electromagnetic valve 63 for a preset second setting period, the control device 6 opens the electromagnetic valve 63 again. As a result, the shift clutch control valve 61 is closed. This is instantaneous contact control, and the control device 6 repeats this instantaneous contact control a predetermined number of times. When the predetermined number of instantaneous contact controls are completed, the timer is cleared and the period measurement is restarted.

  By the way, the first setting period is set to a value at which the connection feeling may be deteriorated due to the decrease in the oil amount and the difference in the oil temperature, or a value shorter than that. Since this value varies depending on the characteristics of the hydraulic circuit and hydraulic oil, it is obtained in advance through experiments.

  Further, the period (second setting period) in which the electromagnetic valve 63 is closed in the instantaneous contact control is set to be shorter than the period necessary for the transmission clutch 3 to be completely connected. That is, this period is set so that the speed change clutch 3 is not completely connected by instantaneous contact control. This is to prevent the vehicle from moving due to the transmission clutch 3 being connected. Of course, when the instantaneous contact control is executed, since the gear position of the transmission T / M is a parking or neutral position, the vehicle does not start even if the transmission clutch 3 is completely connected. So, in order to implement a double safety measure, this is the setting. The instantaneous contact control is not intended to increase the oil pressure in the oil supply line 69 but to supply and fill the oil on the oil pan 45 side into the oil supply line 69, so that the transmission clutch 3 is completely connected. It depends on the reason that it is not necessary to supply oil.

  The number of times that the instantaneous contact control is executed is sufficient to fill the oil supply line 69 with oil (to a level equivalent to that in the normal state) in consideration of the characteristics of the hydraulic circuit and the like. The value is set such that the difference from the oil temperature in the oil supply line 69 is reduced to an acceptable level. In addition, by repeatedly exchanging oil between the oil pan 45 side and the oil supply line 69 side, oil filling, air discharge, and temperature difference correction can be effectively performed. It is preferable to execute at least twice.

  Here, when the present applicant examined the oil temperature in the oil pan 45 and the change in the oil temperature in the oil supply line 69, the oil temperature in the oil pan 45 is higher than the oil temperature in the oil supply line 69. It was found that the temperature dropped quickly, which caused a temperature difference between the two. This is presumably because the oil pan 45 is closer to the outside air than the oil supply line 69.

  In consideration of this, it is preferable to execute the instantaneous contact control even when the oil temperature measured by the temperature sensor 40 becomes equal to or lower than a preset temperature.

  That is, if the oil temperature in the oil pan 45 has decreased to some extent even if the gear position of the transmission T / M is parked or in the neutral position within the first set period, It is possible to estimate that there is a possibility that there is a difference between the oil temperature of the oil and the oil temperature in the oil supply line 69. In this case as well, it is preferable to execute instantaneous contact control to reliably prevent deterioration of the connection feeling. .

  The present invention is not limited to the above embodiment.

  For example, the power transmission device is shown as an example, and can be applied to other power transmission devices such as those equipped with an automatic transmission. That is, the present invention can be applied to any type of power transmission device as long as it has an automatic clutch control means for controlling connection / disconnection of the transmission clutch 3 using hydraulic pressure.

It is the schematic of the power transmission device to which the automatic clutch control apparatus which concerns on one Embodiment of this invention is applied. It is explanatory drawing of the working hydraulic circuit of a transmission clutch.

Explanation of symbols

2 Fluid coupling 3 Shift clutch 5 Lock-up clutch 6 Control device 20 Temperature sensor (oil temperature measuring means)
40 Gear position sensor E Engine T / M Transmission

Claims (3)

When the gear position of the transmission is a parking or neutral position, the clutch control means for disengaging the clutch, and the gear position of the transmission is the parking or neutral position. A period measuring means for measuring a certain period, and a hydraulic circuit for supplying oil maintained at a predetermined oil pressure to the clutch, the clutch control means,
When the clutch is disengaged, supply of oil from the hydraulic circuit to the clutch is shut off, and when the clutch is engaged, oil is supplied from the hydraulic circuit to the clutch,
When the period of time that is measured continuously by the period measuring means becomes a first setting period, and executes the instantaneous engagement control at least once for operating the clutch only contact direction second setting period Automatic clutch control device. Oil temperature measuring means for measuring the temperature of the oil in the oil pan is further provided,
The clutch control means includes
2. The automatic clutch control device according to claim 1, wherein the instantaneous contact control is executed at least once even when the temperature measured by the oil temperature measuring means is equal to or lower than a set temperature.   3. The automatic clutch control device according to claim 1, wherein the instantaneous contact control is such that the clutch is operated in the contact direction for a period shorter than a period necessary for the clutch to be completely connected.

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