JPH0488213A - Inching control method for clutch type automatic transmission - Google Patents

Abstract

PURPOSE:To prevent occurrence of shock and engine stall at the starting time by memorizing the relation between a clutch stroke and the operation rate of an inching pedal and the relation that the larger the difference in respect to an actual stroke is, the smaller the clutch moving speed is, and thereby controlling the clutch moving speed. CONSTITUTION:Signals detected from sensors 1 to 5 for vehicle speed, an inching pedal stroke, forward/reaward gear positions, first and second speed gear positions, and a clutch stroke are input to a CPU 7 together with a signal from a ROM 8 through an A/D converter 6. The relation between the clutch stroke and operating rate of the inching pedal, and the relation that the larger the difference between the rate and the actual clutch stroke is, the smaller the clutch moving speed is, are input to the ROM 8. With the calculation result of the CPU 7, a D/A converter 9, an actuator driving circuit 11, a clutch controlling actuator 10 are driven and the clutch moving speed is controlled. It is thus possible to prevent occurrence of shock and engine stall at the starting time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inching control method for an industrial vehicle equipped with a clutch type automatic transmission.

[Conventional technology]

The relationship between the amount of depression of the inching pedal and the clutch stroke (amount of engagement) for inching control in conventional industrial vehicles equipped with a clutch-type automatic transmission is shown in Figure 2. The clutch is kept in a connected state, and after being depressed to a certain extent, the clutch becomes disengaged relative to the amount of depression. Furthermore, in the relationship shown in FIG. 2, if the vehicle is stopped by operating the inching pedal alone and the foot is released from the inching pedal, the clutch will be engaged and the engine will either stall or the vehicle will suddenly start.

Therefore, conventionally, when the foot is released from the inching pedal, the clutch stroke returns only halfway, and the clutch is maintained in a disengaged state.

[Problem to be solved by the invention]

As mentioned above, if the vehicle stops after the inching pedal is depressed once, and the inching pedal is then depressed again, the relationship shown in Figure 2 will be restored, and the clutch that was started to be depressed will suddenly This caused the vehicle, which had been stopped, to suddenly start, making it impossible to slowly start the vehicle in this case.

The present invention was conceived in consideration of the above-mentioned problems, and when starting by using the inching pedal, the larger the difference between the clutch stroke corresponding to the amount of depression of the inching pedal and the actual clutch stroke, the slower the clutch movement speed can be. It is an object of the present invention to provide an inching control method for a clutch type automatic transmission that allows running without shocks or engine stalls when starting.

[Means to solve the problem]

In order to achieve the above object, the inching control method for a clutch type automatic transmission according to the present invention includes: an inching pedal stroke detection means, a forward/reverse gear position detection means;
It has a second gear position detecting means, a clutch stroke amount detecting means, and a memory device, and the CPU calculates based on the input values from each of the above means and the pressure value from the memory device, and the output signal is used to detect the clutch. In the inching control method for a clutch type automatic transmission that controls engagement content, the storage device stores the relationship between the inching pedal depression amount and the clutch stroke, the clutch stroke corresponding to the inching pedal depression amount, and the actual clutch. A relationship is stored in which the larger the difference is, the slower the clutch movement speed is, and when the inching pedal is first depressed, an output signal from the memory device is used to correspond to the amount of inching pedal depression. The moving speed of the clutch is controlled according to the difference between the clutch stroke and the actual clutch stroke.

[For production]

When starting with the inching pedal, the larger the difference between the clutch stroke corresponding to the amount of depression of the inching pedal and the actual clutch stroke, the slower the clutch movement (engagement) speed becomes, resulting in unforeseen shocks, engine stalling, etc. when starting. Can run.

〔Example〕

Embodiments of the present invention will be described based on the drawings.

FIG. 1 is a control block diagram of an industrial vehicle equipped with a clutch type automatic transmission to which the method of the present invention is applied. In the figure, 1 is a vehicle speed sensor that detects vehicle speed, and 2 is a sensor that detects the depression stroke of an inching pedal. Inching pedal stroke detection sensor, 3 is a forward/reverse gear position detection sensor that detects the switching position of forward and backward gears, 4 is a 12th gear detection sensor that detects the respective shift positions of 1st gear and 2nd gear, 5 is a clutch This is a clutch stroke detection sensor that detects the stroke amount. The detection signals from these detection sensors are input to a CPU (central processing unit) 7 via an A/D converter 6, and are subjected to predetermined arithmetic processing by the CPU 7. Reference numeral 8 denotes a ROM (storage device) for storing data in advance and importing it into the CPU 7 at any time. 9 is a D/A converter that converts the signal from the CPU 7 into D/A, 10 is a clutch control actuator that controls the clutch, and 11 is a clutch control actuator 10 that controls the clutch control actuator 10 based on the signal from the D/A converter 9. This is an actuator drive circuit to control.

The ROM 8 stores maps shown in FIGS. 2 and 3. Figure 2 shows the relationship between the amount of inching pedal depression and the clutch stroke, and this is similar to that of the inching pedal of the conventional clutch type automatic transmission mentioned above, and the relationship is similar to that of the inching pedal of the conventional clutch type automatic transmission described above. When the vehicle stops in this state, the clutch is disengaged to prevent the engine from stalling. The disengaged position of this clutch is set to the closest position to the clutch engagement side within the range where the clutch does not rotate.

Therefore, when the inching pedal is depressed for an inching start, the clutch stroke will be A(
However, as mentioned above, from the viewpoint of preventing the engine from stalling at this time, the clutch stroke is in the N (disengaged) position.

Now, if you are depressing the inching pedal to make an inching start, and the amount of depressing is I, it is necessary to gradually engage the clutch until the clutch stroke reaches M.

The present invention relates to the moving speed of the clutch at this time.

FIG. 3 shows the relationship between the clutch movement speed ratio (%) and the difference Cm between the clutch stroke Cm corresponding to the amount of depression of the inching pedal and the actual clutch stroke C. In Fig. 3, when the actual clutch stroke C matches the clutch stroke Cm corresponding to the amount of depression of the inching pedal, the ratio to the normal clutch movement speed becomes 100%, and the larger the difference Cn, the smaller it becomes. This is done so that the speed ratio becomes the same.

An inching control method according to the present invention using the above configuration will be explained based on the block diagram of FIG.

Now, a signal indicating that (1) the vehicle is stopped, (2) the forward/reverse gear is in forward or neutral position, and (3) the inching pedal is not depressed is detected by the vehicle speed sensor 1, detecting the forward/reverse gear position. When input from the sensor 3 and the inching pedal stroke detection sensor 2 to the CPU 7 via the A/D converter 6, the CPU 7 sends a signal to the D/A converter 9, the actuator drive circuit 11, and the clutch to make the clutch wait in the disengaged position. The signal is output to the control actuator 10, and the clutch is put on standby in the disengaged position.

Next, when the inching pedal is depressed, the inching pedal stroke detection sensor 2 detects the stroke amount of the inching pedal, for example, 1 in FIG. It is detected by the detection sensor 4.

Then, the CPU 7 retrieves the map shown in FIG. 2 from the ROM 8 and calculates Cm1-C7-Cn1. Note that Cm1 is the clutch stroke corresponding to the depression amount 11 of the inching pedal, which is stored as a map shown in FIG.

Further, the CPU 7 next retrieves the map shown in FIG. 3 from the ROM 8 and determines the moving speed ratio of the clutch to Cm1, and then the actual clutch stroke C1 is the clutch stroke corresponding to the amount of depression of the inching pedal. The predetermined clutch movement speed V when the value matches the predetermined clutch movement speed V. From, v1 Tomi v. xKlX is calculated, a signal is output from the CPU 7 so that the clutch moves at the speed of this vl, and the D/A converter 9, actuator drive circuit 11, and clutch control actuator 10
The clutch is controlled at the speed V above.

At the point when the actual clutch stroke corresponds to the clutch stroke corresponding to the amount of depression of the inching pedal, for example after M in FIG. It moves depending on the relationship between the amount of depression and the clutch stroke.

The vehicle stops with the forward and reverse gears in forward or neutral position,
When the inching pedal is turned OFF in this state, the relationship shown in Figure 2 is canceled, and when the inching pedal is pressed again, the clutch moves at the speed shown in Figure 3 until the actual clutch reaches point M. .

〔Effect of the invention〕

According to the present invention, when starting by using the inching pedal, the larger the difference between the clutch stroke corresponding to the amount of depression of the inching pedal and the actual clutch stroke, the slower the clutch movement speed v1 can be, and the shock at the time of starting can be reduced. You can drive without any problems such as engine stalling. As the above-mentioned difference becomes smaller, the engagement speed becomes faster, and smooth latch engagement can be performed in a relatively short time.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the inching control system, Fig. 2 is a diagram showing the relationship between the amount of inching pedal depression and clutch stroke, and Fig. 3 is a graph showing the relationship between the amount of inching pedal depression and the actual clutch stroke. FIG. 3 is a diagram showing the relationship between the ratio of clutch movement speed and the difference in speed. 2 is an inching pedal stroke detection sensor, 3 is a forward/reverse gear position detection sensor, 4 is a 1.2 speed gear position detection sensor, 5 is a clutch stroke detection sensor, 7 is a CPU,
8 is a ROM, 10 is a clutch control actuator, 1
1 is the actuator drive circuit.

Claims (1)

[Claims] It has an inching pedal stroke detection means, a forward/reverse gear position detection means, a 1st and 2nd speed gear position detection means, a clutch stroke amount detection means, and a storage device, and the input values from each of the above means and the storage device are CPU based on output value
In the inching control method for a clutch type automatic transmission in which the clutch engagement amount is controlled by the output signal of For the difference between the clutch stroke corresponding to the amount of depression of and the actual clutch stroke, a relationship is stored in which the larger this difference is, the slower the clutch movement speed is. An inching control method for a clutch type automatic transmission, characterized in that the moving speed of the clutch is controlled according to the difference between the clutch stroke corresponding to the amount of depression of the inching pedal and the actual clutch stroke using an output signal.