JPH0321531A - Inching control method for industrial vehicles - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inching control method for an industrial vehicle such as a forklift truck equipped with a direct transmission.

[Conventional technology]

The conventional industrial vehicles mentioned above are equipped with a new inching pedal, which corresponds to the clutch of a direct transmission, and during normal driving, the engine rotation is controlled simply by operating the accelerator pedal, making it work just like an automatic (AT) vehicle. When the vehicle is inching, both the inching pedal and the accelerator pedal are depressed to control the inching.

[Problem to be solved by the invention]

With the conventional inching control method described above, during normal driving, it becomes like an AT vehicle and is easy to control, but when inching, the operation method is the same as that of a normal direct vehicle, and the inching control method that is most often performed as in forklift trucks is Inching control was troublesome because the inching pedal had to be operated each time.

The present invention has been made in consideration of the above, and provides an inching control method for an industrial vehicle that allows the operation to be performed with the same operational feeling as an AT vehicle, and also allows inching control to be operated with the same feeling as in normal times. The purpose is to

[Means to solve the problem]

In order to achieve the above object, in an inching control method for an industrial vehicle according to the present invention, when the inching switching means is operated, the engine is accelerated by an amount sufficient to secure sufficient driving force for driving the work equipment and driving for inching. The clutch is controlled based on the relationship between the accelerator pedal depression amount and the half-clutch amount, which is recorded in advance in the controller, so that the vehicle speed corresponding to the maximum accelerator pedal depression amount becomes the maximum inching vehicle speed suitable for inching operation. to perform the inching operation.

Also, during inching, the engine accelerator opening is opened by an amount sufficient to secure sufficient driving force for driving the work equipment and driving for inching, and the accelerator pedal depression amount is the same as the normal accelerator pedal depression until the maximum inching vehicle speed suitable for inching operation is reached. The inching operation is performed by controlling the half-clutch, which is recorded in advance in the controller to match the vehicle speed, and by controlling the clutch so that the speed does not increase even if the accelerator pedal is further depressed.

[For production]

During inching, the vehicle speed is increased or decreased to the maximum inching vehicle speed in accordance with the amount of depression of the accelerator pedal 6 while sufficient driving force is secured for driving the working device and for driving the inching operation.

Furthermore, in vehicle speed control during inching, the relationship between the amount of depression of the accelerator pedal 6 and the vehicle speed is normal up to the maximum inching vehicle speed, and the speed will not be increased for further depression of the accelerator pedal 6.

〔Example〕

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

Figure 1 shows the inching control system of an industrial vehicle such as a forklift truck. 1 is a power switch, 2 is an inching lever, 3 is a brake pedal depression amount detector that detects the amount of depression of the brake pedal 4, and 5 is an accelerator pedal. An accelerator pedal depression amount detector detects the amount of depression of the pedal 6, 7 is a range lever for changing gears, and 8 is a forward/forward/stop switching lever. Further, 9 is an engine rotation speed detector that detects the rotation speed of the engine 10, 11 is a human power shaft rotation speed detector that detects the rotation speed of the human power shaft of the transmission 12, and 13 is an output shaft that detects the output shaft rotation speed of the transmission 12. 1 is a rotation speed detector; 14 is an engine rotation control device that controls the rotation of the engine 12; 15 is an engine rotation control position detector that detects the position of this rotation control device;
6 is a main clutch control device that controls the main clutch 16a to engage/disengage and half-clutch; 17 is a main clutch control stroke detector that detects the stroke of this main clutch control device 16; 18 is a forward/reverse stop switching device; A forward/reverse stop switching detector detects the switching position of the forward/reverse stop switching device 18, 20 is a transmission device that switches between high speed and low speed, and 21 is a shift position detector that detects the shift position thereof. 22 is a driving wheel.

Reference numeral 23 denotes a controller, and this controller 23 performs calculations based on signals manually inputted from each of the above-mentioned detectors and levers, and outputs the signals as control signals to each driving section. 24 is a display device.

In the above configuration, it is activated by turning on the power switch 1. By operating the range lever 7 and the forward/reverse switching lever 8, an activation signal is manually input to the controller 23, and a signal based on this manual signal is output as a control signal to the forward/reverse switching device 18 and the transmission 20. and set to a predetermined combination of speeds.

During normal driving, the amount of depression of the accelerator pedal 6 is detected by the pedal depression amount detection amount detector 3, the amount is taken into the controller 23, and a signal based on this is output to the engine rotation control device 14 to control it. At the same time, the engine speed is controlled by a map predefined by the controller 23 based on the relationship between the detection signal of the engine speed detector 9 and the control amount of the engine speed control device 14.

The main clutch 16a is switched on and off to transmit the driving force of the engine 10 to the drive wheels 23.

When the range lever 7 is switched, the clutch 16a is disengaged, and the speed of the transmission 12 is smoothly shifted while detecting the rotation speed of the engine 10, the rotation speed of the human power shaft, and the output shaft using the respective detectors 15, 11, and 13. The engine speed or the half-clutch state is controlled by a controller, and the clutch 16a is connected after shifting.

The vehicle speed V during normal driving is controlled in proportion to the amount of depression of the accelerator pedal 6, as shown by the dotted line A in FIG.

During inching, the operator switches the inching lever 2 to turn it on. Next, the engine rotation control device 14 opens the accelerator opening to a certain point by an amount sufficient to secure sufficient driving force for driving the work equipment and driving the inching operation. In this state, the clutch 16a is controlled to be in a half-clutch state, and the vehicle speed corresponding to the maximum depression amount of the accelerator pedal 6 is set to the maximum inching vehicle speed v suitable for the inching operation. ．． The clutch 16a is controlled to be a half-clutch according to the relationship between the amount of depression of the accelerator pedal 6 and the half-clutch, which is recorded in advance in the controller 23 so as to hold the clutch 16a to a half-clutch. Hereinafter, the vehicle speed changes depending on the amount of depression of the accelerator pedal 6. At this time, the amount of depression of the accelerator pedal 6 and the vehicle speed V are as shown by the solid line B in FIG. V. ．． ．． It changes in proportion to the amount of depression of the accelerator pedal 6.

The control at the time of inching has a flow as shown in FIG.

To cancel inching, the operator turns off the inching lever 2. As a result, the accelerator opening degree returns to the normal opening degree, the clutch operation is controlled in accordance with the normal control map, and the vehicle speed 2 relative to the amount of depression of the accelerator pedal 6 becomes as shown by the dotted line A in FIG.

In the above embodiment, during inching, the maximum inching vehicle speed v. ．． Accelerator pedal to 6
Although we have shown an example in which the accelerator pedal 6 changes in proportion to the amount of depression, as shown by the polygonal line C in Fig. 4, up to the maximum inching vehicle speed V8, which is suitable for inching operation, the normal amount of depression of the accelerator pedal 6 and the vehicle speed change. The relationship may be such that the vehicle speed does not increase even if the accelerator pedal 6 is further depressed.

In this case, after the operator turns on the inching lever 2, the engine rotation control device 14 is operated only when the operator turns on the inching lever 2, and then the engine rotation control device 14 Open the accelerator to a certain point. In this state, clutch control is performed as follows.

That is, the maximum inching vehicle speed vsa suitable for the inching operation is determined based on the amount of depression of the accelerator pedal 6.
Until x, the half-clutch control recorded in advance in the control 23 is performed so that the normal relationship between the amount of depression of the accelerator pedal 6 and the vehicle speed (changes along the dotted line A) is achieved, and when the accelerator pedal 6 is depressed any further. However, the clutch 16a is controlled so that the speed does not increase.

In any of the above cases, the rotation speed of the engine 10 is high during inching, so vehicle speed control is performed by the clutch 16.
This is achieved by setting a to a half-clutch state.

〔Effect of the invention〕

According to the present invention, during inching, the vehicle speed can be increased or decelerated to the maximum inching speed according to the amount of depression of the accelerator pedal 6 while sufficient driving force is secured for driving the working device and driving for the inching operation. The vehicle can be operated with the same operational feeling as an automatic vehicle by using a normal accelerator pedal 6 without using an inching pedal.

In addition, in the vehicle speed control during inching, the relationship between the amount of depression of the accelerator pedal 6 and the vehicle speed is normal up to the maximum inching vehicle speed, and the speed is not increased for further depression of the accelerator pedal 6. Even if the working device is operated during inching, the normal speed will be maintained up to the maximum inching vehicle speed with the normal amount of pedal depression, so the operator can operate with the same feeling as normal. In addition, the amount of pedal depression required during normal and inching is the same, and the speed is the same up to the maximum inching vehicle speed, so even if switching is set to "normal" and the operator thinks it is inching, the operator can press the same pedal. Since the amount of depression is set to a certain amount, cases that lead to runaway are reduced.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is an explanatory drawing showing the control system of an industrial vehicle, FIG. 2 is a flowchart, and FIGS. 3 and 4 are diagrams showing the relationship between vehicle speed and accelerator pedal depression amount. It is a line diagram showing a relationship. 2 is an inching lever, 3 is a brake pedal depression amount detector, and 4 is a brake pedal. 5 is an accelerator pedal depression amount detector, 6 is an accelerator pedal, 7 is a range lever 8
9 is an engine rotation speed detector, 10 is an engine, 12 is a transmission, 13 is an output shaft rotation speed detector, 14 is an engine rotation control device, 1
5 is an engine rotation control position detector, 16 is a main clutch control device, 16a is a main clutch, 17 is a main clutch stroke detector, 18 is a forward/reverse stop switching device,
One is a forward/reverse stop switching detector, 20 is a transmission, 21 is a shift position detector, and 23 is a controller.

Claims (2)

[Claims] (1) A main clutch 16a that is located between the engine 10 and the transmission 12 and connects and disconnects the transmission of the output of the engine 10, a main clutch control means that can control the main clutch 16a to be in the disconnected and half-clutch state, and a main clutch control means that controls the amount of movement of the main clutch. A main clutch movement amount detecting means for detecting, a forward/reverse switching means for switching between forward and reverse and its position detecting means, a transmission means for switching gears, a vehicle speed detecting means for detecting the traveling speed of the vehicle, and an accelerator pedal. an accelerator amount detection means for detecting the operation amount of 6;
An engine rotation control means, an engine rotation speed detection means,
In a work vehicle equipped with a brake actuation means and an inching operation switching means, when the inching switching means is operated, the accelerator opening of the engine 10 is adjusted by an amount sufficient to secure sufficient driving force for driving the working equipment and driving for inching. Then, the clutch 16a is opened according to the relationship between the amount of depression of the accelerator pedal 6 and the half-clutch amount, which is recorded in advance in the controller 23 so that the vehicle speed for the maximum amount of depression of the accelerator pedal 6 becomes the maximum inching vehicle speed suitable for inching operation. A method for controlling inching in an industrial vehicle, characterized by performing control. (2) In the work vehicle according to claim 1, when inching, the accelerator opening of the engine 10 is opened by an amount sufficient to secure sufficient driving force for driving the work equipment and driving for inching, and the opening degree of the accelerator of the engine 10 is opened by an amount suitable for the inching operation. Until the maximum inching vehicle speed, half-clutch control is performed that is recorded in advance in the controller so that the normal relationship between the amount of depression of the accelerator pedal 6 and the vehicle speed is maintained, and the speed does not increase even if the accelerator pedal 6 is further depressed. A method for controlling inching in a work vehicle, characterized by performing clutch control.