JP2002021882A - Clutch speed detecting method and clutch control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify control. SOLUTION: In this clutch speed detecting method and clutch control method in controlling the connection/disconnection of a friction clutch by a hydraulic actuator on the basis of the connection/disconnection command of a control unit, residence time ta, tb, tc, etc., when the clutch acts in specified stroke width a, b, c, etc., are clocked, and the stroke width is divided by the residence time to obtain clutch speed a/ta, b/tb, c/tc, etc. The detected clutch speed is compared with specified target speed a/Ta, b/Tb, c/Tc, etc., to perform the feedback control of the clutch every stroke width.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clutch speed detecting method and a clutch control method applied to an auto clutch vehicle or the like capable of automatically connecting and disconnecting a friction clutch.

[0002]

2. Description of the Related Art Conventionally, there has been known an automatic clutch vehicle which automatically connects and disconnects a friction clutch based on a connection / disconnection command of a control unit (see Japanese Patent Application No. 10-48394).

[0003]

When performing clutch speed control in such a vehicle, generally, normal feedback control is performed. That is, the amount of change in the clutch stroke is detected every predetermined unit time, and the amount of change is divided by the unit time to obtain the clutch speed. Then, this is compared with a predetermined target speed, and the speed of the clutch is adjusted.

However, there are times when it is not necessary to perform such detailed control, for example, when the clutch is disconnected. At this time, if the above-described feedback control is performed, the control becomes too fine, and the control may be unnecessarily complicated. That is, the unit time is on the order of an extremely short time, usually several tens of msec. If there is no need to control every short time so far, it is convenient if there is a method that can be controlled more easily.

Accordingly, an object of the present invention is to provide a clutch speed detecting method and a clutch control method that can simplify control.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a clutch speed detecting method for controlling the connection / disconnection of a friction clutch by a fluid pressure actuator based on a connection / disconnection command of a control unit, wherein the clutch has a predetermined stroke width. Is measured and the stroke width is divided by the stay time to obtain the clutch speed.

Here, the entire clutch stroke may be divided for each predetermined stroke width, and the clutch speed may be detected for each stroke width.

A clutch control method according to the present invention compares the clutch speed detected by the clutch speed detection method with a predetermined target speed and performs feedback control of the clutch for each stroke width.

[0009]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a configuration diagram of an auto clutch vehicle to which the present invention is applied. This auto clutch vehicle is equipped with a so-called selective auto clutch device. The selective auto clutch device is configured such that a normal friction clutch is used for the clutch 1 and the clutch is manually connected / disconnected by the manual connection / disconnection means 2 or automatically connected / disconnected by the automatic connection / disconnection means 3. The figure shows a state in which the clutch 1 is connected and none of the means is operated.

The clutch 1 is stroked in the connecting / disconnecting direction by reciprocating the clutch fork 4 by a slave cylinder 5 (which constitutes the "fluid pressure actuator" of the present invention). A hydraulic pressure (fluid pressure) serving as a clutch operating force is supplied to the slave cylinder 5 from the intermediate cylinder 6. The intermediate cylinder 6 is connected to the master cylinder 7 or the hydraulic pressure source 8
The hydraulic pressure according to the hydraulic pressure supplied from the slave cylinder 5
Send to The master cylinder 7 generates a hydraulic pressure according to the depression amount (operation amount) of the clutch pedal 9 and sends it to the intermediate cylinder 6. The hydraulic source 8 includes an electric motor 10, a hydraulic pump 11, a check valve 32, solenoid valves 30, 31 and a relief valve 13, and the electronic control unit 14 controls the drive of the motor 10 and the solenoid valves 30, 31 to supply hydraulic pressure. Eliminate. Oil as a working fluid is stored in an oil tank 15.

The duty of the solenoid valves 30 and 31 is controlled by the control unit 14. Here, a normally closed solenoid valve, that is, a solenoid which is closed when OFF and opened when ON is used. Solenoid valves 30, 31 are used for clutch connection. Each of the solenoid valves 30 and 31 has a different oil discharge port diameter. Therefore, three types of clutch connection speeds (low speed, medium speed, or high speed) can be selected by changing the combination of ON / OFF of these solenoid valves 30, 31. The relief valve 13 is provided for fail-safe opening when the oil pressure rises abnormally, and is normally closed.

In this configuration, the manual connection and disconnection of the clutch 1 is performed as follows. First, when the clutch pedal 9 is depressed from the illustrated state, hydraulic pressure is generated in the master cylinder 7. The hydraulic pressure simultaneously pushes two pistons 16 and 17 inside the intermediate cylinder 6 in the same direction as indicated by the solid arrow, and the hydraulic pressure corresponding to the pedal depression amount is supplied from the intermediate cylinder 6 to the slave cylinder 5. Then, the internal piston 18 is pushed in the slave cylinder 5, whereby the clutch fork 4 is pushed, and the clutch 1 is operated to the disconnection side by an amount corresponding to the pedal depression amount. When the return operation of the clutch pedal 9 is performed, the oil is returned as indicated by the dashed arrow, and the clutch 1 is operated to the connection side. At this time, the pistons 16 and 17 of the intermediate cylinder 6 are pushed back to the normal position by the return spring 37. Thus, manual connection / disconnection is achieved, and the manual connection / disconnection means 2 is constituted by the clutch pedal 9, the master cylinder 7, the intermediate cylinder 6, and the slave cylinder 5.

The method for automatically connecting and disconnecting the clutch 1 will be described later.

The clutch stroke (clutch position) is constantly detected by the clutch stroke sensor 19. The clutch stroke sensor 19 is a potentiometer operated by the clutch fork 4 via the link 36. The clutch stroke sensor 19 is configured to output a larger voltage as the clutch stroke is more divided. A hydraulic switch 33 is provided at the outlet of the intermediate cylinder 6. This turns on when the outlet pressure of the intermediate cylinder 6 rises to a certain set value. These sensors 19
And the signal of the switch 33 is sent to the control unit 14.

The vehicle is equipped with a normal transmission (manual transmission) 20. The transmission 20
The gear is mechanically connected to the shift lever 23 through a mechanical connecting means 57 such as a link or a wire cable, and the speed is changed in conjunction with the shift lever operation by the driver.

The shift lever 23 is a shift lever device 21.
Part of. That is, the shift lever device 21 includes the shift lever 23, the shift knob 22 forming a gripping portion thereof, and the knob switch 62 built in the shift knob 22. The shift knob 22 can slightly swing (swing) in the shift direction with respect to the shift lever 23, and is normally held at the center position by a built-in spring, but swings when a predetermined shift force is applied, and the knob switch 62 is turned on.

The transmission 20 has a shift stroke sensor 34 for detecting a shift stroke of an internal shifter lever, and a neutral switch 24 for detecting that the shifter lever is at a neutral position.
And a select stroke sensor 35 for detecting a stroke of the shifter lever in the select direction. The control unit 14 detects the current gear position (current gear position) of the transmission 20 based on signals from these sensors and switches.

Here, a method for automatically connecting and disconnecting the clutch 1 will be described. It is assumed that the driver gives a shift force to the shift knob 22 in an attempt to change gears while traveling at a predetermined gear. Then, the shift knob 22 slightly swings and the knob switch 62 is turned ON,
In response to this, the control unit 14 sends a clutch disconnection command to the automatic disconnecting / connecting means 3, and specifically starts the motor 10. Then, the hydraulic pump 11 is started to generate a hydraulic pressure, and this hydraulic pressure pushes the check valve 32 open as shown by the solid arrow to reach the intermediate cylinder 6. In the intermediate cylinder 6, the pistons 16 and 17 are pushed in the separating direction. Accordingly, the piston 17 on the outlet side further pressurizes the oil on the outlet side and supplies the oil to the slave cylinder 5. When this happens, the piston 18 of the slave cylinder 5 pushes the clutch fork 4 to disconnect the clutch 1.

The control unit 14 stops the motor 10 when it recognizes that the clutch is completely disconnected based on the signal of the clutch stroke sensor 19. Thereafter, the hydraulic pressure is held by the check valve 32, and the clutch 1 is disconnected and held. During this time, the driver continuously operates the shift lever, and the transmission 20 is shifted to the next gear.

The control unit 14 recognizes the gear-in from the signals of the shift stroke sensor 34 and the select stroke sensor 35, and
To start the clutch 1 connection control. Specifically, at least one of the solenoid valves 30 and 3
1 is turned ON, and slave cylinder 5
And the clutch fork 4 is returned to connect the clutch 1. At this time, the optimal combination of ON / OFF of the solenoid valves 30 and 31 is selected in consideration of the connection state of the clutch, the degree of depression of the accelerator, and the operation state of the engine and the vehicle, and the duty control for these solenoid valves is performed. Is performed. As a result, the clutch is connected at the optimum speed.

As described above, the hydraulic power source 8, the intermediate cylinder 6, and the slave cylinder 5 form the automatic connection / disconnection means 3.

Switching between manual connection and automatic connection / disconnection is performed by a changeover switch 25 provided in the vehicle interior.

Here, when the vehicle starts, the following start control is executed. That is, it is assumed that the driver has operated the shift lever 23 from neutral to the start stage in order to start the vehicle. Then, prior to the operation of the shift lever 23, the shift knob 22 swings and the knob switch 62 is turned on. In response to this, the clutch 1 is automatically disengaged, and the transmission 20 is brought into the starting stage by the continued shift lever operation. Thereafter, the clutch is held and the accelerator is depressed, and when the driver depresses the accelerator pedal 38, the clutch 1 is automatically connected together with the engine rotation according to the amount of depression.

For such start control and the like, an accelerator opening sensor 39 for detecting the amount of depression of the accelerator pedal 38, that is, the accelerator opening, is provided. Accelerator opening sensor 3
A potentiometer 9 outputs a voltage signal proportional to the accelerator opening. An accelerator idle switch 40 is provided in the vicinity of the accelerator pedal, and is turned on when the accelerator pedal 38 is in the idle region and turned off when the accelerator pedal 38 is depressed beyond the idle region. The outputs of the sensor 39 and the switch 40 are sent to the control unit 14.

The accelerator pedal 38 is mechanically connected to an engine output control mechanism 41 via mechanical connecting means 42 such as wires and links. Here, the engine 43 is a diesel engine, and the engine output control mechanism 41 is a mechanical governor attached to the fuel injection pump 44. However, it is possible to use a gasoline engine, in which case the engine output control mechanism is a throttle valve. The engine 43 is provided with an engine speed sensor 45 for detecting the engine speed (specifically, the crankshaft speed), and the output is sent to the control unit 14.

The transmission 20 is provided with an output shaft rotation sensor 63 for detecting the output shaft rotation speed thereof.
Converts the vehicle speed based on the output of the sensor 63.

In this automatic clutch vehicle, the following clutch speed control is executed. That is, when the clutch is disconnected,
The clutch disengaging speed in the half clutch region is changed according to the clutch stroke. 2 and 3 show the contents of this speed control. In the figure, the horizontal axis represents time, and the vertical axis represents clutch stroke. V _L clutch Kanse' position corresponding value (referred End tangent value) (referred Kandanchi) V _H clutch fully disconnected position equivalent value, V _XL is contact-side boundary position corresponding values of the half clutch region (contact V _XH is a value corresponding to the disengaged boundary position of the half-clutch region (referred to as disengaged boundary value), V ₁
Is a value slightly closer to the contact side than the disconnection side boundary value V _XH (referred to as a contact side set value), and V ₂ is a value slightly closer to the disconnect side than the disconnection side boundary value V _XH (referred to as a disconnect side set value).

FIG. 3 shows a target speed U corresponding to each clutch stroke input to the control unit 14 in advance.
It represents the _1, U _2. That is, the control unit 1
4 feedback-controls the clutch so that the actual disconnection speed approaches the target speed.

In this case, the clutch disengaging speed U ₁ is high between the complete contact value V _H and the contact side set value V ₁ , and is low between the contact side set value V ₁ and the disengage side set value V _2. of U _2, between the cross-sectional side setting value V ₂ until fully disconnected value V _H is a high-speed U _1. That is, in the cross-sectional course of the clutch, the cross-sectional speed when the actual clutch stroke reaches the contact side setting value V ₁ is switched from U ₁ to U _2, the actual clutch stroke after this reaches a sectional side setting value V ₂ cross speed is switched from U ₂ to U _1. As described above, the clutch disengagement speed is changed within the half-clutch region, and when the clutch exceeds the disengagement boundary position (disengagement boundary value V _XH ) of the half-clutch region, the low U
It becomes ₂ .

For example, when the clutch is suddenly disengaged from the half-clutch state during starting or the like, the torsional torque applied to the drive system is released at once, causing problems such as clutch disconnection shock and swing back. Since clutch disconnection shock the clutch is generated at the moment of being cut from the half clutch state (moment to escape from the half clutch region), the clutch disconnection shock can be reliably prevented by exceeding this way the cross-sectional side boundary position at a low speed U ₂ .

For this reason, the disconnection speed control is executed during the start control. FIG. 2 shows the situation at this time. In the same figure, the solid line shows how the clutch stroke changes when the start connection is performed as usual.
The broken line shows a state in which the driver depresses the accelerator and the clutch is disengaged during half-clutch in the case of traveling at a low speed or the like. As shown on the left side of the broken line, if the value A between the clutch stroke of the clutch cutting start of the contact-side set value V ₁ and the cross-sectional side boundary value V _XH, are clutch disconnection at low speed U _2, as the cross-sectional side boundary _{Exceeding the} value V _XH prevents clutch disconnection shock. Sectional speed when the clutch stroke after this reaches a sectional side setting value V ₂ is changed to a high-speed U _1, the clutch is quickly Kanse'.

On the other hand, as shown in the right-hand broken line, if the value B between the clutch stroke of the clutch cutting start is the contact side setting value V ₁ and the contact-side boundary value V _XL, until contact side setting value V ₁ The clutch is disengaged at high speed U ₁ , and low speed U ₂ at contact side set value V ₁
And exceeds the disconnection side boundary value V _{XH as it} is. This also prevents clutch disconnection shock.
Clutch disconnection speed is switched to a high-speed U ₁ again if the clutch stroke after this Itare intercepted side setting value V ₂ is Kanse'.

Here, the latter example is a case where the clutch is disconnected from a relatively deep half-clutch state. At this time, if the clutch is disengaged at low speed from the beginning, the entire disconnection time will be longer,
Are clutch disconnection fast until contact side setting value V _1. Further, the former example does the same, but the clutch stroke is switched to the cross-sectional velocity When turned sectional side setting value V ₂ at a high speed. As a result, it is not necessary to prolong the entire disconnection time, and the disconnection time can be reduced while preventing the clutch disconnection shock. Conversely, the speed should be _reduced only when the value exceeds the disengagement boundary value V _XH , and at other times it is preferable to disengage the clutch at a high speed.

Here, the present device also executes clutch control (vehicle speed control) based on the vehicle speed. This means that when the vehicle speed increases to a certain value in the clutch disengaged state, the clutch is connected, and conversely, when the vehicle speed decreases to the fixed value Q in the clutch engaged state, the clutch is disconnected, as shown in FIG. For example, when the brake pedal is released from a state in which the vehicle is waiting to start on a downhill (vehicle speed is zero, the brake is operating, the clutch is disconnected, and the gear is engaged), the vehicle starts idling (coasting) and descends down the hill. If the vehicle speed keeps increasing, the clutch will be engaged when the vehicle speed reaches a certain level, and the engine brake will be applied. On the other hand, when the vehicle is being decelerated while applying the engine brake during normal running, the clutch is disconnected when a sufficiently low vehicle speed is reached to prevent engine stall.

In particular, in the latter vehicle speed disconnection control, the clutch disconnection speed control is executed. That is, since the torsional torque is accumulated in the drive system by the engine brake, releasing it at a stretch causes a shock. Therefore, as shown in FIG. 4, the disconnection speed is changed to a low speed when exceeding the disconnection side boundary value V _XH to solve this problem.

By the way, the following two methods are available for changing the clutch disengagement speed. One is called a leak type, in which the motor 10 is rotated at the maximum speed to keep the discharge amount of the hydraulic pump 11 at the maximum, while the duty ratio of the duty signal given to the solenoid valve 30 or 31 is changed, and the oil leak amount is adjusted to This is a method of changing the speed of the cylinder 5. This method has been conventionally used.

The other is called a motor control type, and the motor 1
This is a method of directly controlling the duty of 0, changing the duty ratio, changing the discharge amount of the hydraulic pump 11, and changing the speed of the slave cylinder 5. This method is a novel method unique to the present apparatus. The motor control type can reduce the motor operation noise because the motor speed can be made lower than the leak type, and the operation noise is eliminated because the solenoid valve is not operated, which is advantageous in terms of noise.

The clutch stroke sensor 19
Is a potentiometer, the output of which is an analog signal. On the other hand, the control unit 14 is configured to digitally process various signals. Therefore, the control unit 14 converts an analog signal of the clutch stroke sensor 19 into a digital signal.

Further, in the present apparatus, the clutch disconnection speed detection and the clutch feedback control when the clutch is disconnected are performed by a method different from the conventional one. That is, in the conventional method, the amount of change in the clutch stroke is detected at every predetermined unit time, and the amount of change is divided by the unit time to obtain the clutch disengagement speed. Then, this is compared with a predetermined target speed to perform feedback control of the clutch every unit time.

On the other hand, in this apparatus, the stay time of the clutch when the clutch operates a predetermined stroke width is measured, and the stroke width is divided by the stay time to obtain the clutch disengagement speed. Then, the clutch disengagement speed is compared with a predetermined target speed which is determined in advance, and the clutch is feedback-controlled at every predetermined stroke width. That is, here, the detection of the clutch disengagement speed and the clutch control are performed based not on the time but on the clutch stroke width.

This will be described in detail. As shown in FIG. 5, here, the entire clutch stroke (digital value) from complete connection to complete disconnection is divided into a plurality of blocks in advance, and feedback control is executed for each block. Each block has a stroke width of a bit number larger than 1, and has a stroke width of a bits, b bits,. Here, all clutch strokes are equally divided, and a = b = c... = G.

In the clutch disengagement process, the time during which the actual clutch stroke stays in one block (residence time) is counted by a timer, and the stroke width (the number of bits) in one block is divided by the residence time. Is the actual clutch disengagement speed in the block.

For example, suppose that the stay time is ta in the first block starting from the complete contact position (digital value = a ₀ ). In other words, it is assumed that it takes time ta for the digital value of the clutch stroke to change from a ₀ to b ₀ in the clutch disconnection process. Then, the clutch disconnection speed in this block becomes a / ta. Similarly, in the next block starting with digital value = b ₀ , b / t
b, c / t in the next block starting with digital value = c ₀
c. The actual clutch disengagement speed determined in this way is compared with target speeds a / Ta, b / Tb, c / Tc... Input in advance to the control unit 14, and the clutch is feedback-controlled. In comparison, the digital value of the boundary point of each block, that is, the clutch stroke is b ₀ , c _0.
... when it becomes.

In the illustrated example, the target speeds a / Ta, b /
Tb corresponds to the previous U ₁ , and the target speed c / Tc corresponds to the previous U ₂
Is equivalent to c ₀ and d ₀ correspond to the contact side setting value V ₁ and the disconnection side setting value V ₂ . In the first block larger than the actual cross-sectional speed a / ta is the target speed a / Ta, the cross-sectional speed is adjusted in the decreasing direction when the digital value of this for the clutch stroke becomes b _0. In the next block, the cutting speed b / tb is smaller than the target speed b / Tb. When the digital value of the clutch stroke becomes c ₀ , the target speed c / Tc is decreased, and the actual speed c / Tc is accordingly reduced.
tc has also been reduced. When the digital value of the clutch stroke becomes d ₀ , the target speed is increased again, and the actual disconnection speed is also increased.

In this method, ta, tb,... Or T
so that a, Tb,... becomes larger than the conventional unit time,
The stroke widths a, b,... Are set so as to be at least several times the conventional unit time. Therefore, according to this method, it is not necessary to perform the feedback control for each unit time, which is usually a very short time (ex. 32 msec), and the control is simplified. In this method, if the control is rougher than before, but there is no need to finely control the clutch,
This is particularly effective when the clutch is disconnected. If there is an area that requires the finest control, the conventional method can be used only for that area, and the other method can be partially applied to adopt this method. The method of dividing the clutch stroke is not limited to the equal division, and the stroke width in one block can be set arbitrarily. As a method of changing the cutting speed, any of the above-mentioned leak type and motor control type is possible.

As described above, the present invention can adopt various other embodiments. For example, in the present embodiment, the case where the clutch is disconnected has been described, but the present invention is also applicable to the case where the clutch is engaged. In other words, the "clutch speed" in the present invention includes both the speeds of disconnection and connection. The clutch may be a wet multi-plate clutch or the like, and the “friction clutch” of the present invention includes such a clutch. The "fluid pressure actuator" can be modified, and a fluid pressure other than the hydraulic pressure (for example, pneumatic pressure) can be used.

[0048]

In summary, according to the present invention, an excellent effect that control can be simplified is exhibited.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an auto clutch vehicle to which the present invention is applied.

FIG. 2 is a time chart showing the content of clutch disengagement speed change control.

FIG. 3 shows the content of the same control, and shows a clutch disengagement target speed.

FIG. 4 is a diagram showing the details of vehicle speed division control.

FIG. 5 is a diagram for explaining a clutch disengagement speed detection method and a clutch control method according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Friction clutch 5 Slave cylinder 8 Hydraulic source 10 Electric motor 11 Hydraulic pump 14 Control unit 19 Clutch stroke sensor 30, 31 Solenoid valve U ₁ High-speed clutch disconnection speed U ₂ Low-speed clutch disconnection speed ta, tb, tc Stay time a, b, c, d, e, f, g Stroke width in one block (number of bits)

Continuation of the front page (72) Inventor Kazuhiko Kobayashi 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture Inside Transtron Co., Ltd. (72) Hiroyuki Arai 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa No. F term in Transtron Inc. (reference) 3J057 AA07 BB02 GA12 GA49 GA66 GB02 GB05 GB12 GB15 GB27 GB36 GC04 GC10 GE05 GE08 HH01 JJ01

Claims (3)

[Claims] 1. A clutch speed detecting method for controlling connection and disconnection of a friction clutch by a hydraulic actuator based on a connection / disconnection command of a control unit, wherein a stay time when the clutch operates a predetermined stroke width is determined. A clutch speed detecting method characterized in that the clutch speed is measured and the stroke width is divided by the stay time to obtain a clutch speed. 2. The clutch speed detecting method according to claim 1, wherein the entire clutch stroke is divided for each predetermined stroke width, and the clutch speed is detected for each stroke width. 3. A clutch control method comprising: comparing a clutch speed detected by the clutch speed detection method according to claim 1 with a predetermined target speed to perform feedback control of the clutch for each stroke width.