JPS61105236A - Inching control device for industrial vehicle equipped with dry type single plate clutch - Google Patents

Abstract

PURPOSE:To enable an inching operation to be accurately controlled by comput ing the connecting condition of a clutch based on the manipulated variable of the inching a allowing the connection data to be read out from ROM so as to controla clutch drive device when the inching is detected. CONSTITUTION:While a fork lift is driven forward, when an inching pedal 20 is stepped, the inching is detected by an inching sensor 19 allowing the connec tion data for the inching operation in response to the pedal travel of the stepped pedal 20 to be read out from ROM 25 in CPU 24. Then, the stroke computted based on the connection data is compared with the actual stroke detected by a stroke sensor 14 allowing a clutch control actuator 6 to be controlled in its operation. When a rod 6a reaches the stated stroke, the actuator 6 is stopped allowing a dry type single plate clutch 2 to be in the stated connecting condition.

Description

[Detailed Description of the Invention] Purpose of the Invention (Field of Industrial Application) This invention relates to an industrial vehicle such as a forklift equipped with an automatic transmission equipped with a dry single-plate clutch, and more specifically, the present invention relates to an industrial vehicle such as a forklift equipped with an automatic transmission equipped with a dry single-plate clutch. This invention relates to an inching control device that controls connections.

(Prior Art) Today, there are forklift trucks equipped with automatic transmissions with dry single-plate clutches. Then, during normal driving, the amount of accelerator operation and driving speed are detected, and based on the amount of rain detected.
Automatic gear shifting was performed and a dry single-plate clutch was turned on and off.

(Problem to be Solved by the Invention) However, when this type of forklift performs an inching operation, when the accelerator is pressed to raise the fork, the traveling speed also increases at the same time. There was a problem as it was not possible to do so.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an object of the present invention is to provide an inching control device for an industrial vehicle equipped with an automatic transmission equipped with a dry single-plate clutch that allows inching operations to be performed in the same manner as a conventional manual transmission. It is in.

Structure of the Invention (Means for Solving the Problems) In order to achieve the above object, the present invention provides a dry single plate clutch that turns on and off the output of an engine and transmits the output to an automatic transmission; A clutch driving means that operates a dry single plate clutch and controls the connection state of the clutch, a vehicle speed detector that detects the traveling speed of the vehicle, an accelerator opening degree detector that detects the operating amount of the accelerator pedal, and A first storage device in which a shift range corresponding to each driving state based on the amount of accelerator pedal operation is stored in advance as shift data, and a drive speed detected by the vehicle speed detector and the amount of operation detected by the accelerator opening detector. a first indexing means for determining the running state at that time and reading out corresponding shift data from the first storage device; In an industrial vehicle equipped with an automatic transmission equipped with a dry single-plate clutch, the inching detector detects an operating state of an inching operation device, and a first control means for controlling the speed change state of the dry single-plate clutch is connected. a clutch detector that detects the state; a second storage device that stores in advance the connection state of the dry single-plate clutch with respect to the inching operation amount as connection data for the inching operation; and an inching operation based on the inching detector. When detected,
a second determining means for determining a clutch connection state for an inching operation based on the operation amount of the inching operation device at that time, and reading out corresponding connection data from the second storage device; and a second control means for driving the clutch drive means and controlling the dry single-plate clutch to a predetermined connected state based on the clutch connected state detected by the clutch detector at that time. The gist of this paper is an inching control device for an industrial vehicle equipped with an automatic transmission with a single-plate clutch.

(Function) When an inching operation is detected based on the inching detector, the second indexing means indexes the clutch connection state for the inching operation based on the operation amount of the inching operation device at that time, and the second storage device Read the corresponding connection data from. Then, the second control means controls the clutch drive based on the read connection data and the current clutch connection state detected by the clutch detector so that the dry single plate clutch is in a predetermined connection state for inching operation. Drive and control the means.

(Embodiment) Hereinafter, a preferred embodiment in which the present invention is embodied in a forklift will be described with reference to the drawings.

Figure 1 shows the mechanism of the drive system of a forklift, in which the output of the engine 1 is transmitted through a dry single-plate clutch 2 to an automatic transmission 3.
The automatic transmission 3 drives the running drive wheels 5 forward and backward at a predetermined gear ratio via the differential gear mechanism 4. The dry single plate clutch 2 that turns on and off the output of the front engine 1 has a rod 6a that extends based on the drive of a clutch control actuator 6 as a clutch drive means.
The connection state of the clutch 2 is adjusted relative to the stroke amount.

The engine 1 is also used as a drive source for 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.

On the other hand, the automatic transmission 3 can shift between 1 (fast, low speed) and 2 (fast, high speed) by driving the shift switching actuator 7, and can change between forward traveling and backward traveling by driving the forward/reverse switching actuator 8. can be switched to

Next, an electric circuit for driving and controlling each of the actuators 6 to 8 will be explained with reference to FIG.

A vehicle speed sensor 11 serving as a vehicle speed detector detects the rotational speed of the output shaft of the automatic transmission 3, as shown in FIG. 1, and outputs the detection signal to the input/output interface 12. The engine rotation speed sensor 13 detects the rotation speed of the output shaft of the engine 1, as shown in FIG. 1, and outputs the detection signal to the interface 12.

The stroke detection sensor 14 as a clutch detector is composed of a potentiometer and detects the stroke of the rod 6a of the clutch control actuator 6, and the detection signal is converted into a digital signal by the A/D converter 15 and sent to the interface 12. is output to.

The accelerator opening sensor 16, which serves as an accelerator opening detector, is composed of a potentiometer and detects the amount of depression of an accelerator pedal 17 provided at the driver's seat, and the detection signal is converted into a digital signal by an A/D converter 18. The signal is output to the interface 12.

The inching sensor 19, which serves as an inching detector, is composed of a potentiometer and detects the amount of depression of the inching pedal 20, which serves as an inching operation device provided at the driver's seat.The detected signal is converted into a digital signal by an A/D converter 921. and output to the interface 12.

A forward/reverse movement detection sensor 22 detects the switching state (forward, neutral, reverse) of a forward/reverse movement switching lever 23 provided at the driver's seat, and outputs the detection signal to the interface 12.

A central processing unit (CPU) 24 as first and second indexing means and first and second control means is stored in read-only memory (hereinafter referred to as ROM) 25 as first and second storage devices. The sensor operates according to a control program that has been created, and inputs detection signals from each of the sensors through the input/output interface 12.

The CPU 24 determines the amount of depression of the accelerator pedal 17 based on the detection signal from the accelerator opening sensor 16, and determines the traveling speed of the forklift based on the detection signal from the vehicle speed sensor 11. And CPU2
4 drives a throttle actuator (not shown) based on the calculated amount of depression of the accelerator pedal 17 to control the opening degree of the engine throttle, thereby controlling the rotational speed of the engine 1. Note that the throttle opening degree relative to the amount of depression of the accelerator pedal 17 is set in advance, and the data is stored in the ROM 25.

Further, the CPU 24 determines the stroke amount of the rod 6a of the clutch control actuator 6, that is, the connection state (connection degree) of the dry single plate clutch 2, based on the detection signal from the stroke detection sensor 14, The inching processing operation is executed based on the detection signal from the inching sensor 19, and the presence or absence of depression of the inching pedal 20 and the amount of depression are determined.

Then, when the inching pedal 20 is depressed, CP'
tJ 24 determines the degree of engagement of the dry single plate clutch 2 for inching operation, that is, the stroke amount of the rod 6a of the clutch control actuator 6, based on the determined depression amount of the inching pedal 20. ing.

In this embodiment, the stroke amount of the rod 6a with respect to the depression amount of the inching pedal 20 is set in the relationship shown in FIG. 3, and data for this (connection data) is stored in the ROM 25 in advance. This third
According to the stroke amount of the rod 6a with respect to the amount of depression of the inching pedal 20 shown in the figure, when the inching operation is started and the amount of depression of the inching pedal 20 reaches a predetermined amount or more, the stroke is thereafter proportional to the amount of depression. The amount is short, that is, the degree of engagement of the dry single plate clutch 2 is reduced.

Then, during the inching operation, the CPIJ 24 compares the stroke amount calculated based on the connection data with the current stroke amount calculated based on the detection signal from the stroke detection sensor 14, and controls the clutch control actuator 6. It is determined whether the rod 6a has a stroke amount based on the connection data, that is, whether the dry type single plate clutch 2 is in a predetermined connected state. rod 6
If a is not in the stroke amount based on the connection data, CP
The U24 outputs a drive control signal to the input/output interface 12 and the actuator drive circuit 26 to drive the clutch control actuator 6 to obtain a stroke amount based on the connection data.

Then, when the predetermined stroke amount (connected state) is reached,
The CPU 24 stops driving the control actuator 6 to maintain the stroke amount (connected state).

In addition, the CPU 24 determines the optimum speed change state for the current driving condition based on the detection signals from the vehicle speed sensor 11 and the accelerator opening sensor 14 except during the inching operation. Then, the CPU 24 outputs a drive control signal to the actuator drive circuit 27 via the input/output interface 12 based on the determined shift state to drive the shift switching actuator 7 to change the shift state of the automatic transmission 3 to 1. Switch to speed or 2nd speed. At this time of switching,
The CPU 24 outputs a drive signal to the actuator drive circuit 26 to drive the clutch control actuator 8 to disconnect the dry single plate clutch 2. Note that the speed change state for this running state is set in advance, and the speed change data is stored in the ROM 25.

Further, the CPU 24 switches the forward/reverse switching lever 23 (forward, neutral, reverse) based on the detection signal from the forward/reverse detection sensor 22.
Based on the switching, a drive control signal is output to the actuator drive circuit 28 via the interface 12 to drive the forward/reverse switching actuator 8 to set the automatic transmission 3 to the forward, neutral, or reverse state. Switch to At this time of switching, the CPU 24 outputs a drive signal to the actuator drive circuit 26 to drive the clutch control actuator 8 to disconnect the dry single-plate clutch 2, as described above.

Note that readable and rewritable memory (hereinafter referred to as RA)
29 (referred to as M) is designed to temporarily store various calculation results of the CPU 24.

Next, the operation of the forklift constructed as described above will be explained.

Now, when you step on the inching pedal 2o to perform an inching operation while driving forward, the inching sensor 19
detects the depression of the inching pedal 20 and outputs a detection signal to the CP (J24) via the A/D converter 21 and the interface 12.The CPU 24 executes an inching process operation in response to this detection signal, and The connection data for the inching operation for the determined depression m of the inching pedal 2o is stored in the ROM 25.
Read from. The CPU 24 compares the stroke amount of the rod 6a determined based on this connection data with the current stroke amount determined based on the detection signal from the stroke detection sensor 14.

Then, the CPLJ 24 determines whether the rod 6a of the clutch control actuator 6 is at the stroke amount based on the connection data, that is, whether the dry type single disc clutch 2 is in a predetermined connected state. control the drive. rod. 6a reaches a predetermined stroke m, the CPIJ 24 stops driving the control actuator 6 to maintain the stroke amount, and brings the dry single plate clutch 2 into a predetermined connected state.

Therefore, at the same time as the inching operation is performed, the CPU 2
4 will perform the processing operation for the inching operation. Moreover, at this time, as shown in FIG. 3, the connection state of the dry single-plate clutch 2 decreases in proportion to the amount of depression of the inching pedal 20 (half-clutch state), and is finally disengaged. As a result, the engine 1 and automatic transmission 3 are turned off and torque transmission is cut off.

As described above, in this embodiment, even if the accelerator pedal 17 is pressed to increase the speed of the fork's vertical movement after the inching pedal 20 is pressed and the engine 1 is revved, the torque transmission is controlled, so the traveling speed of the forklift does not increase. Instead, the speed will be adjusted. Therefore, even though the forklift is equipped with the automatic transmission 3, it is possible to perform a quick and highly safe inching operation with a feeling similar to that of a conventional manual transmission.

Note that the present invention is not limited to the above embodiments,
For example, in the embodiment, the rod 6 of the clutch control actuator 6 corresponds to the amount of depression of the inching pedal 20.
Stroke amount of a (dry single.

Although the connection state of the plate clutch 2 is controlled according to the relationship shown in FIG. 3, it may be changed as appropriate depending on various work purposes. The actuators 6 to 8 can most easily be implemented in a conventional forklift by using hydraulic cylinders, but they may also be implemented by using linear motors or the like.

Effects of the Invention As described above, the present invention has an excellent effect in that even though it is an industrial vehicle equipped with an automatic transmission, it is possible to perform an agile and highly safe inching operation with the feeling of a conventional manual transmission. has.

[Brief explanation of the drawing]

Fig. 1 is a mechanical diagram showing the drive system mechanism of a forklift embodying the present invention, Fig. 2 is an electrical block circuit diagram of the forklift, and Fig. 3 shows the relationship between the rod of the clutch control actuator and the amount of depression of the inching pedal. FIG. 3 is a diagram showing the relationship between stroke amounts. Engine 1, dry single plate clutch 2, automatic transmission 3, clutch control actuator 6, rod 6a, shift switching actuator 7, forward/reverse actuator 8, vehicle speed sensor 11, stroke detection sensor 14, accelerator opening sensor 16, Accelerator pedal 17, inching sensor 1
9, inching pedal 20, forward and backward movement detection sensor 22, C
PU 24, ROM 25゜Patent applicant Toyota Industries Corporation Fuji
Tsu Co., Ltd.

Claims (1)

[Scope of Claims] A dry-type single-plate clutch that turns on and off the output of the engine and transmits the output to an automatic transmission; and a clutch drive means that operates the dry-type single-plate clutch and controls the connection state of the clutch. , a vehicle speed detector that detects the traveling speed of the vehicle, an accelerator opening degree detector that detects the amount of operation of the accelerator pedal, and a shift range corresponding to each driving state based on the traveling speed and amount of operation of the accelerator pedal is stored in advance as shift data. Determines the driving state at that time based on the first storage device that has been stored, the driving speed detected by the vehicle speed detector and the operation amount detected by the accelerator opening detector,
a first indexing unit that reads corresponding gear shift data from the first storage device; and a first indexing unit that operates the clutch driving unit and the automatic transmission to control a predetermined gear shift state based on the read gear shift data. In an industrial vehicle equipped with an automatic transmission with a dry single-plate clutch, the inching detector detects the operating state of the inching operation device, and the clutch detector detects the connected state of the dry single-plate clutch. , a second storage device that stores in advance the connection state of the dry single-plate clutch with respect to the inching operation amount as connection data for the inching operation; and when the inching operation is detected based on the inching detector, the inching at that time a second indexing means for determining a clutch connection state for an inching operation based on an operation amount of an operating device, and reading corresponding connection data from the second storage device; and the read connection data and the clutch detector. a second control means for driving the clutch drive means and controlling the dry single-plate clutch to a predetermined connected state based on the clutch connection state detected at that time. Inching control device for industrial vehicles equipped with automatic transmissions.