JP2647869B2 - Method of determining half-clutch position of clutch - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining a half-clutch position of a clutch of a vehicle having an automatic transmission.

[Conventional technology]

2. Description of the Related Art Conventionally, in a vehicle equipped with an automatic transmission, a half-clutch position based on a flowchart shown in FIG. The decision has been made.

That is, the control device determines in step S31 that the transmission is in the neutral state, and in step S32 determines that the vehicle speed is "0", then determines in step S33 whether the clutch is "disengaged". If the clutch is not "disengaged", the clutch is disengaged in step S34.
If the clutch is "disengaged", the process proceeds to step S35 and waits until the rotation of the input shaft of the transmission stops.

If the control device determines in this step S35 that the rotational speed of the clutch is "0", the process proceeds to step S36 to slowly connect the clutch. If it is determined in step S37 that the input shaft has started to rotate, the process proceeds to step S37.
In S38, the clutch position at that time is stored as a half-clutch position, and in the following step S39, the clutch is completely connected, and the half-clutch position determination process ends.

Based on the learned value of the half-clutch position obtained in step S38, the half-clutch control at the time of starting and shifting is performed so that stable half-clutch control can be performed even if the clutch is worn.

[Problems to be solved by the invention]

Now, in order to rotate the input shaft from the stop state, a torque that overcomes the viscosity of the transmission oil is required. When the viscosity is high, that is, when the oil temperature of the transmission oil is low, the torque is large and the viscosity is low. When the oil temperature is low, that is, when the oil temperature is high, the torque is small. As shown in FIG. 3, between the transmission oil temperature and the input shaft rotation reduction time, the rotation reduction time is shorter when the oil temperature is lower, and the rotation is lower when the oil temperature is higher. There is a relationship that the decline time is prolonged.

However, in the conventional method for determining the half-clutch position described above, the oil temperature of the transmission oil is not taken into account. There is a problem that the clutch engagement amount becomes excessive and the starting shock and shift shock increase. In addition, when the temperature of the transmission oil increases due to the heat when the clutch is hot due to heavy use of the half clutch, the viscosity of the transmission oil decreases and the position of the half clutch is learned by the deformation of the clutch plate due to the heat. The value shifts to the disengaged side, and the clutch connection amount becomes insufficient during starting and shifting,
There is a problem that the vehicle slips due to the slip of the clutch.

The present invention has been made to solve the above problems, and has an object only when the deceleration state of the rotation speed of the input shaft that is correlated with the oil temperature of the transmission oil is within a predetermined reference range. By determining the half-clutch position, the variation of the half-clutch position is limited within a reference range, and the clutch connection amount is excessive when the transmission oil temperature is low, or the clutch connection amount is insufficient when the transmission oil temperature is high. It is an object of the present invention to provide a clutch half-clutch position determining method capable of performing a stable half-clutch control by preventing the occurrence of a shift and improving the feeling at the time of starting and shifting.

Configuration of the Invention [Means for Solving the Problems] In order to achieve the above object, the present invention completely changes a clutch that completely turns off a clutch that turns on and off the output of an engine and transmits the output to a transmission. In the clutch half-clutch position determining method for determining the half-clutch position of the clutch at the time based on the state of the input shaft of the transmission based on the operation of the clutch, the vehicle is stopped. In a state where the transmission to which the output of the engine is transmitted via the clutch is in the neutral position, the clutch is completely disengaged from the connected state, and the rotation of the input shaft of the transmission after the clutch is completely disengaged. Measure the speed deceleration state. A half-clutch position determining method for determining a half-clutch position only when the deceleration state is within a predetermined reference range and not determining a half-clutch position when the deceleration state is out of the reference range. And

[Action]

When the vehicle is stationary and the transmission is in the neutral position,
The clutch is completely disengaged from the connected state, and the deceleration state of the rotation speed of the input shaft of the transmission after the clutch is completely disconnected is measured. Then, the half-clutch position is determined only when the deceleration state correlated with the oil temperature of the transmission oil is within a predetermined reference range, and is not determined when the deceleration state is outside the reference range.
For this reason, the variation of the half clutch position is limited to within the reference range, whereby stable half clutch control is performed,
The feeling at the time of starting and shifting is improved.

〔Example〕

An embodiment in which the present invention is embodied in a forklift will be described below with reference to FIGS.

FIG. 1 shows a mechanism of a drive system of a forklift and an electric block circuit. The output of an engine 1 is transmitted to an automatic transmission 3 via a dry single-plate clutch 2 and the automatic transmission 3
Drives the traveling drive wheels 5 forward and backward at a predetermined gear ratio via the differential gear mechanism 4. The engine 1 is also used as a drive source of a hydraulic pump that supplies hydraulic oil to a lift cylinder for raising and lowering the fork and a tilt cylinder for tilting the mast.

The connection state of the dry single-plate clutch 2 for turning on and off the output of the engine 1 is adjusted relative to the stroke amount of the rod 6a that expands and contracts based on the drive of the clutch control actuator 6. On the other hand, the automatic transmission 3
Can be shifted to first speed (low speed) and second speed (high speed) by driving the shift switching actuator 7, and forward traveling, neutral (neutral position) and reverse traveling by driving the forward / reverse switching actuator 8. And can be switched to

Next, an electric circuit for driving and controlling each of the actuators 6 to 8 will be described.

The vehicle speed sensor 11 detects the rotation speed of the output shaft of the automatic transmission 3 and outputs a detection signal to the input / output interface 12. The rotation speed sensor 13 detects the rotation speed of the input shaft 3a of the automatic transmission 3 and outputs a detection signal to the interface 12. The engine speed sensor 14 detects the speed of the output shaft of the engine 1 and outputs a detection signal to the interface 12.

The stroke detection sensor 15 is composed of a potentiometer and detects the stroke amount of the rod 6a of the clutch control actuator 6, that is, the clutch connection state. The detection signal is converted into a digital signal by an A / D converter 16 and Output to 12.

The accelerator sensor 17 is composed of a potentiometer and detects the amount of depression of an accelerator pedal 18 provided in the driver's seat. The detection signal is converted into a digital signal by an A / D converter 19 and output to the interface 12.

The forward / reverse detection sensor 20 is provided with a switching state (forward, neutral, reverse) of a forward / reverse operation lever 21 also provided in the driver's seat,
That is, a direction point is detected, and a detection signal is output to the interface 12.

A central processing unit (hereinafter, referred to as CPU) 31 inputs detection signals from the sensors via the input / output interface 12 and operates according to a control program stored in a storage device 32. Further, the CPU 31 is connected to the input shaft 3a.
In this embodiment, a timer 31a for measuring the deceleration state, that is, the rotation reduction time, is provided.

The CPU 31 determines the stroke amount of the rod 6a of the clutch control actuator 6, that is, the connection state of the dry single-plate clutch 2 based on the detection signal from the stroke detection sensor 15. Further, the CPU 31 determines the depression amount of the accelerator pedal 18 based on the detection signal from the accelerator sensor 17.

Each index is determined based on the connection and depression amount data for the respective detection signals of the stroke detection sensor 15 and the accelerator sensor 17 stored in the storage device 32 in advance.

Then, the CPU 31 determines the engine speed corresponding to the determined accelerator pedal depression amount based on the data stored in the storage device 32 and sets the determined engine speed via the input / output interface 12 and the throttle actuator drive circuit 22 to determine the engine speed. The number of rotations of one is controlled.

The CPU 31 determines the start of operation of the accelerator pedal 18 based on the detection signal from the accelerator sensor 17, and when the CPU 18 determines that the pedal 18 is not operated, the clutch 2 is completely disengaged. The clutch control actuator 6 via the interface 12 and the clutch actuator drive circuit 23.
Drive control.

Further, the CPU 31 determines the direction point of the forward / reverse operation lever 21 at that time based on the detection signal from the forward / backward detection sensor 20, and through the interface 12 and the forward / backward actuator drive circuit 24, the forward / reverse switching actuator. 8 and controls the interface based on a detection signal from the accelerator sensor 17.
12 and the shift actuator drive circuit 25 are driven and controlled.

The CPU 31 calculates the vehicle speed of the forklift based on the detection signal from the vehicle speed sensor 11, and
The rotation speed of the input shaft 3a is calculated on the basis of the detection signal from 13. Then, the CPU 31
When the vehicle speed is "0", that is, the forklift is in a stopped state, and the forward / reverse switching actuator 8 is in a neutral (neutral position) state, the input shaft 3a is in a completely disconnected state in which the clutch 2 is completely disengaged. When the rotation speed is "0", the clutch 2 is slowly operated in the connection direction, and the stroke of the rod 6a of the clutch control actuator 6 when the input shaft 3a starts rotating based on the operation of the clutch 2 is reduced by half. The clutch position is determined.

The determination of the half-clutch position, rotation reduction time T is the reference range T ₂ through T ₁ a predetermined input shaft 3a with a correlation with the oil temperature or viscosity of the mission oil (T _2> T ₁₎ when within a The half-clutch position is not determined when it is out of the reference range.This limits the amount of shift of the half-clutch position to the connection side or the disconnection side within the reference range, and reduces the transmission oil oil. Excessive clutch connection when the temperature is low, or shortage of clutch connection when the oil temperature is high is prevented. Fully disengage the clutch 2 at a high speed when the speed reduction time T to the input shaft 3a is rotated by the engine 1, the rotational speed N of the input shaft 3a after completely disconnected the clutch 2 is defined from the predetermined value N ₂ This is the time until the value decreases to N ₁ (N ₂ > N ₁ ), and is measured by the timer 31a.

Next, the operation of the forklift constructed as described above will be described with reference to the flowchart shown in FIG.

First, the CPU 31 determines that the transmission 3 is in the neutral state in step S1, and the vehicle speed is "0" in step S2.
That is, when it is determined that the forklift is in a stopped state,
Proceeding to step S3, the clutch actuator drive circuit 23
To operate the clutch 2 in the connection direction. When the CPU 31 determines that the clutch 2 is completely connected in step S4, the CPU 31 disengages the clutch 2 at high speed in step S5. In the following step S6, the process waits until the clutch 2 is turned off, and the operation of the clutch 2 is stopped in step S7.

Subsequently, the CPU 31 determines in step S8 that the input shaft 3
It determines that the rotational speed N> specified value N ₂ of a, determination result is to start time measurement by the timer 31a proceeds to step S9 when is N ₂ ≧ N. With CPU31 discriminates whether the rotational speed N> specified value N ₁ of the input shaft 3a, the determination result is finished the counting by the timer 31a proceeds to step S11 If it is N ₁ ≧ N in the subsequent step S10 Then, the measured rotation reduction time T is stored in the storage device 32.

Thereafter, the CPU 31 determines in step S12 that the input shaft
Waiting for the rotation speed of the input shaft 3a to become "0", and when the rotation speed of the input shaft 3a becomes "0", the process proceeds to step S13, where the clutch actuator drive circuit 23 is operated to operate the clutch 2 slowly in the connection direction.

The CPU 31 determines in step S14 whether the rotation speed of the input shaft 3a is "0", and the determination result is "0".
That is, when the input shaft 3a starts rotating, the process proceeds to step S15, and the stroke amount of the rod 6a, that is, the position CL of the clutch 2 is stored in the storage device 32 based on the signal from the stroke detection sensor 15 at that time. .

At subsequent step S16, CPU 31 discriminates whether the input shaft 3a rotation reduction time T> or reference value T ₂ of the stored in the step S11, when the determination result is T ₂ ≧ T, the process proceeds to step S17. In step S17 CPU 31 will determine whether the speed reduction time T <reference value T _1, the determination result is T
If it is ≧ T _1, to determine the position CL of the clutch 2 stored in the step S15 proceeds to step S18 as half-clutch position, a process of determining the half-clutch position completely connect the clutch at subsequent step S19 finish.

Then, the CPU 31 starts and controls the half-clutch at the time of shifting based on the learned value of the half-clutch position obtained in step S18.

Now, as shown in FIG. 3, the viscosity of the transmission oil increases with a decrease in its temperature, and the input shaft 3a
In the conventional method, as shown in FIG. 4, the shift of the half-clutch position to the connection side for rotating the input shaft 3a up to the point A as shown in FIG. In this case, the half-clutch position of the clutch 2 is determined only when the rotation reduction time T of the input shaft 3a satisfies the reference value T ₂ ≧ T ≧ reference value T ₁ , and when the rotation reduction time T <the reference value T ₁ , the clutch 2 Is determined, the shift of the half-clutch position toward the connection side can be limited to the point B, thereby preventing an excessive connection amount of the clutch 2 during starting and shifting. As a result, stable clutch control can be performed, and stable starting and shifting feeling can be obtained even at low temperatures.

In addition, as shown in FIG. 3, the viscosity of the transmission oil decreases as the temperature rises, and the rotation reduction time of the input shaft 3a becomes longer, so that the transmission oil oil temperature becomes higher or the half clutch is frequently used. If the temperature of the transmission oil rises due to the heat when the clutch 2 is at a high temperature, as shown in FIG. 4, the shift of the half-clutch position to the disengaged side results in an insufficient connection amount as shown in FIG.
Although than it was to the point, so is not carried out to determine the half clutch position of the clutch 2 when the rotation reduction time T> reference value T ₂ of the input shaft 3a in this embodiment, the cross-sectional side of the half-clutch position Can be up to the point C, and even if the clutch plate is deformed due to heavy use of the half clutch, the vehicle can be moved smoothly by preventing the shortage of the clutch connection amount at the time of starting and shifting, Good starting and shifting feeling can be obtained.

In the above embodiment, the half-clutch position CL of the clutch 2 is measured after the rotation reduction time T of the input shaft 3a is measured.
May be stored, first, the half-clutch position CL of the clutch 2 may be stored, and thereafter, the rotation reduction time T of the input shaft 3a may be measured.

Further, after measuring the rotation reduction time T of the input shaft 3a, if the rotation decrease time T is the reference range T ₂ through T ₁ makes a decision of the half clutch position, if the reference range T ₂ through T ₁ outside The determination of the half clutch position may not be performed.

In the above embodiment, the present invention is embodied in a forklift.
It may be embodied in vehicles such as passenger cars and trucks.

Effect of the Invention As described in detail above, according to the present invention, by limiting the range of variation of the half clutch position, the amount of connection of the clutch is excessive when the oil temperature of the transmission oil is low, or when the oil temperature is high. There is an excellent effect that a stable half-clutch control can be performed by preventing the shortage of the clutch connection amount, and the feeling at the time of starting and shifting can be improved.

[Brief description of the drawings]

FIG. 1 is a mechanism and an electric block circuit diagram of a forklift embodying the present invention, FIG. 2 is a flowchart showing an operation, FIG. 3 is a diagram showing a relationship between a rotation reduction time of an input shaft and a transmission oil temperature, and FIG. FIG. 4 is a diagram showing the variation of the learning value, and FIG. 5 is a flowchart showing the operation of the conventional half-clutch position determining method. In the figure, 1 is an engine, 2 is a dry single-plate clutch, 3 is an automatic transmission, and 3a is an input shaft.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sumi Kitagawa 1015 Uedanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture Within Fujitsu Limited (72) Inventor Seiichi Hata 1015-Ue-Danaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fujitsu Limited (56) References JP-A-60-11722 (JP, A) JP-A-61-205521 (JP, A) JP-A-60-18846 (JP, A) JP-A-60-34525 (JP, A) Kaisho 60-164017 (JP, A)

Claims (1)

(57) [Claims] 1. A clutch for turning on and off the output of an engine and transmitting the output to a transmission is operated in a direction from a completely disconnected state to a completely connected state, based on the operation of the clutch. A half-clutch position determining method for determining a half-clutch position of a clutch based on a state of an input shaft of a transmission, wherein the transmission of an engine output is transmitted via the clutch when the vehicle is in a stopped state. When the clutch is in the neutral position, the clutch is completely disengaged from the connected state, and after the clutch is completely disconnected, the deceleration state of the rotation speed of the input shaft of the transmission is measured, and the deceleration state is within a predetermined reference range. Only when it is at
A half-clutch position determining method for determining a half-clutch position when the position is outside a reference range.