JPH01285425A - Speed controller for crawler - Google Patents

Abstract

PURPOSE:To enable even unskilled drivers to operate with high accuracy by pressing a constant speed switch of a speed controller so as to memorize the speed at the time and make control of a governor device for keeping the constant speed. CONSTITUTION:Output signals from a decelerator 4, an external throttle 5, a transmission 6, a speed means 7, and signals from a brake switch 8 are inputted respectively to the input side of a controller 3. A memory means 9 used for the initial value set is also connected to the controller 3, and the controller 3 outputs control command signals to the control part of a governor device 2. The speed is kept constant by pressing a constant speed switch of the controller 3 so that the controller memorizes the speed at the time and makes control of a governor device 2 for keeping the constant speed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle speed control device for a tracked vehicle such as a bulldozer.

[Conventional technology]

Conventional power lines for bulldozers include direct (%) type, torque flow (T/F) type, and hydraulic drive (HST).
) has a format.

The relationship between vehicle speed V and traction force F of these power lines is shown in Figure 8 for the direct (D/D) type, and Figure 9 for the torque flow (T/F) type. , and in the case of hydraulic drive (H3T) type, the first
The result will be as shown in Figure 0.

In FIGS. 8 and 9, F1 is the first forward speed, F2 is the second forward speed, and F3 is the third forward speed.

In these power lines, direct (D/D)
Matching is performed at point A for the type, 8 points for the torque flow (T/F) type, and 0 point for the hydraulic drive (HST) type, and if the load changes, this will appear as a change in vehicle speed.

[Problem to be solved by the invention]

Bulldozers have a problem in that the vehicle speed changes greatly and does not match the operating speed of the work equipment, especially when unloading during ground leveling or when a sudden load is applied when digging by an inexperienced operator.

The present invention was made in view of the above circumstances, and its purpose is to be able to maintain a constant vehicle stability, and to prevent the vehicle from jumping out or suddenly decreasing speed caused by inexperienced drivers, especially when leveling the ground. The objective is to enable even inexperienced operators to operate the work equipment (blade) in the same manner, allowing them to perform highly accurate work.

[Means to solve the problem]

In order to achieve the above object, the present invention includes an engine governor device, a constant speed switch operation processing section, an initial value setting section for output rotation speed, fuel control amount, and vehicle speed stage, and a constant speed control section. The controller includes a control release command section and an external throttle priority section, and a controller that controls the governor device so that when a constant speed switch is pressed, the vehicle speed at that time is memorized and the vehicle speed is kept constant. .

[For production]

By pressing the constant speed switch, the controller stores the vehicle speed at that time and controls the governor device to maintain the vehicle speed constant.

〔Example〕

The present invention will be explained below based on FIGS. 1 to 7.

Reference numeral 1 in FIG. 1 is an engine, and a governor device 2 that is electrically controlled is attached to this engine 1.

3 is a controller, and the input side of this controller 3 receives an output signal from the dexel 4, an output signal from the external throttle 5, an output signal from the transmission 6, an output signal from the vehicle speed stage 7, and a signal from the brake switch 8. A memory 9 for setting initial values is connected to the controller 3, and the controller 3 outputs a control command signal to the control section of the governor device 2. It is.

A potentiometer is used to detect the output signal from the dexel 4 and the output signal from the external throttle 5, and an electromagnetic pickup is used to detect the output signal from the transmission 6.

The panel switch group is provided with a constant speed switch 10, keys, etc.

FIG. 2 shows a flowchart of constant vehicle speed control. This flowchart is divided into a constant speed switch operation processing section 11, an initial value input section 12, a constant speed control section 13, a control release command section 14, and an external throttle priority section 15.

In the constant speed switch operation processing section 11, the constant speed switch 1
When 0 is pressed once, it is turned on (ON), and initial values such as the output rotation of the transmission 6 are set, and when pressed twice, it is turned off (OFF).

Fy is a control flag to prevent malfunction when constant speed switch 10 is kept pressed, and Fx is constant speed switch 1.
0 is an on (ON)-off (OFF) control flag, Fv is a constant speed control flag, and when a start input is made to the key switch, Fy-0, Fx--1, Fv-0.

In the initial value input section 12, the set value No of the rotation speed of the transmission 6, the set value Tho of the external throttle 5,
The set value Deo of the dexel 4 and the set value So of the vehicle speed stage 7 are set.

Further, the constant speed control section 13 controls the internal throttle so as to keep the rotational speed N of the transmission at a constant set value No.

Further, in the control release command unit 14, the operator controls the external throttle 5, the dexel 4, the brake 8, the vehicle speed change lever 7
If you use , constant speed control will be canceled.

Further, in the external throttle priority section 15, fuel control is controlled by the dexel pedal.

Next, the vehicle speed control device for a work vehicle according to the present invention performs constant vehicle speed control: (1) When constant speed control is turned off (OFF) (2) Constant speed control when the constant speed switch is pressed once (3) Constant speed control Press the switch twice to turn off the constant speed control (OFF) (4) Turn off the constant speed control by operating the throttle, dexel, etc.
The explanation will be divided into four operations (OFF).

(1) When constant speed control is off (OFF) As shown in the flowchart shown in Fig. 3, since the constant speed switch 10 is off (OFF), the control flow is as shown by the solid arrow in the constant speed switch operation process. In section 11, the process goes from step 101 to step 102 to step 103 to step 110, thereby bypassing the initial value set.

At step 110, the constant speed control flag Fv-0 (set to 0 at key start) moves to step 120 without entering the constant speed control section 13, giving priority to the external throttle.

(2) Constant speed control by pressing the constant speed switch once In this case, when you want to maintain a constant vehicle speed, turn on the constant speed switch 10.
None, pilot lamp P/L is lit and constant speed control is entered.

In the case of the first cycle, the control flow is step 100 → step 101 → step 102 → step 1, as shown by the solid arrow in the flowchart shown in FIG.
04 → Step 105 → Step 106 → Step 10
It becomes 7.

That is, since the constant speed switch 10 is ON, the process moves from step 102 to step 104, and Fr-0
Therefore, the process moves to step 104, inputs 1 to F' to become Fr-1, moves to step 105, and inputs Fxsml.
Then, it becomes Fr--Fx, and the process moves from step 106 to step 107.

In step 107, the constant speed switch 1 is changed depending on the value of Fx.
0 (A), (B) ((A) in the operation diagram shown in FIG. 7,
(B)) and determine whether constant speed control is turned on (ON) or turned off (
OFF).

In the operation diagram shown in Figure 7, (1) is ON for the first cycle, (2) is for the first cycle onwards (when the constant speed switch 10 is returned), and (3) is for the first cycle onwards (when the constant speed switch 10 is returned). (When speed switch 10 is not returned) (4) is turned on again (ON) 1st cycle (5) is from 1st cycle onwards (when constant speed switch 10 is returned) (6) is from 1st cycle onwards (when constant speed switch 10 is returned) (when 10 is not returned), is.

In step 107, it is determined that Fx>0, and the process moves to step 108, where initial values are set. In this case, the final value is set so that it always enters when the constant speed switch 10 is kept pressed.

This initial value is the rotation speed number of the transmission 6.

These are the set value Tho of the external throttle 5 and the set value Deo of the dexel 4.

In step 9, the constant speed control flap Fv-1 is set to give priority to the internal throttle.

Step 110 is entered, and since Fv>O, step 111 is entered. In step 111, the tranmilon rotation speed N is input, and the process moves to step 112, where this rotation speed N is compared with an initial value No. If N≦NO-εn, a signal to increase the internal throttle is issued in step 113. If N≧No1εn, a signal to reduce the internal throttle is issued in step 114.

Then, in step 115, the actual value Th of the external throttle 5, the actual value Do of the dexel 4, the actual value S of the vehicle speed change lever 7, and the ON-OFF state of the brake SW 8 are input.

Then, in step 116, the actual value Th of the external throttle 5 and the set value Tho are compared, and 1Th-Thol<
If ε, the process moves to step 117. In step 117, the actual value De of Dexel 4 becomes the set value De.

If De<Deo+εn, the process moves to step 124. In step 122, the actual value S of the vehicle speed change lever 7 is the set value S.

If the result is 5-So, the process moves to step 123. In step 123, it is determined whether the brake SW is ON-OFF, and if it is OFF, the process moves to step 124, where the pilot lamp P/L is turned on and constant speed control is entered.

After the first cycle, the control flow when the constant speed switch 10 is returned is step 101 as indicated by the dotted arrow in FIG.
→ Step 103 → Step 110, and the process is the same as the above case.

Furthermore, after the first cycle, the flow of control when the constant speed switch 10 is not returned is as shown by the two-dot chain line in FIG.
4 → Step 107 = Step 108 → Step 109
- Proceed to step 110, and the rest is the same as above.

That is, when the constant speed switch 10 is kept pressed, since the value is Fr-1 at the first time, PX--Fx is not performed and the process moves to step 107 to set the initial value.

(3) Press the constant speed switch twice (again) to turn off the constant speed control (see the flowchart shown in FIG. 5).

In this case, when the constant speed switch 10 is turned on again, the pilot lamp P/L goes out and the constant speed control turns off (
OFF).

The control flow for the first cycle of turning on again (ON) is step 100 → step 101 → step 102 → step 1
04 → Step 105 → Step 106 → Step 10
7 and the solid line arrows in FIG.

In step 106, the constant speed switch 10 is turned on (O
N) -OFF (OF) control flag Fx becomes -Fx and is distributed in step 107, and since Fx<0, the flow reaches step 118.

In step 11B, the initial values IVo, Tho, and Deo are reset and sorted, and since the constant speed control flag FvmO is set in step 119, step 1
The process moves to step 20, where priority is given to the external throttle, the pilot lamp P/L is turned off (step 124), and the constant speed control is turned off.

Note that since the constant speed control flag Fv-0 is set in step 119, even if the constant speed switch 10 is released, the states (2) and (5) in the operation table are determined in step 110.

After the first cycle, when the constant speed switch 10 is returned,
The control flow is as shown by the dotted arrow in FIG. 5: Step 101 → Step 102 → Step 103 → Step 1
10 → Step 120 → Step 121 → Step 12
It becomes 5.

If the constant speed switch 10 is not returned after the first cycle, the control flow is as shown by the two-dot chain line in FIG. → Go to step 125.

(4) Turn off constant speed control by operating the throttle, dexel, etc.
OFF) FIG. 6 shows the flow when the external throttle, Dexel vehicle speed change lever, and brake are operated during constant speed control.

Point A becomes the starting point when operating the throttle and dexel.

For example, by operating the external throttle 5, its absolute value ITh
- If Thol exceeds the judgment value εt, the initial value No.
is reset and gives priority to the external throttle.

That is, the control flow is as shown by the solid line in FIG. 6: Step 110 → Step 111 → Step 112 → Step 113 (Step 114) → Step 115 → Step 116 → Step 118 → Step 119 → Step 120 → Step → Step 121. →Step 125 follows.

Further, when the absolute value ITh-Thol is smaller than the judgment value εt, the actual value De determined by the dexel operation is Deo+ε.

(ε. is the judgment value), De≧Deo+ε.

In this case, the initial value Deo is reset and priority is given to the external throttle (step 116→step 117→step 118→step 119→step 120).

In step 122, the actual value S of the vehicle speed change lever 7 is compared with the set value So, and if S+So, the initial EfiDe
o is reset to give priority to the external throttle (step 116→step 117→step 122→step 118→step 119→step 120).

If S=S o, the process moves to step 123, and if the brake switch is ON, the initial value De.

is reset and gives priority to the external throttle (step 116 - step 117 → step 122 → step 1)
23→Step 118-Step 119→Step 12
0).

Also, in step 123, the brake switch is turned OFF.
In the case of F, the process moves to step 124.

From the second cycle onward, control is performed as shown by the dashed-dotted arrow.

That is, since the constant speed switch 10 is OFF, steps 103→110→step 120 are performed.
Therefore, priority is given to the external throttle.

In the above-described embodiment, a torque flow (T/F) type power line was described, but in a direct (D/D) type, engine rotation is sensed, and in a hydraulic drive (HST) type, motor rotation is sensed.

〔Effect of the invention〕

As detailed below, the vehicle speed ni of the tracked vehicle according to the present invention
The l l device includes an engine governor device, a constant speed switch operation processing unit, a setting unit for initial values of output rotation speed, fuel control amount, and vehicle speed, a constant speed control unit, a control release command unit, and an external throttle control unit. and a controller that controls the governor device so that when a constant speed switch is pressed, the vehicle speed at that time is stored and the vehicle speed is kept constant.

Therefore, by pressing the constant speed switch, the controller memorizes the vehicle speed at that time, and the controller controls the governor device to keep the vehicle speed constant, thereby keeping the vehicle speed constant.

By keeping the vehicle speed constant in this way, it is possible to prevent the vehicle from jumping out or suddenly slowing down, which can occur especially when inexperienced drivers are using the vehicle, and the work equipment (blade) can be operated at the same pace, allowing even inexperienced drivers to operate the machine with high precision. Work becomes possible.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the configuration of one embodiment of the present invention, Fig. 2 is a flowchart showing the control operation to keep the transmission output rotation speed constant, and Fig. 3 is the control operation when the constant speed control is off (OF). 4 is a flowchart showing the control operation in the case of constant speed control when the constant speed switch is turned on (ON), and FIG. 5 is a flowchart showing the control operation when the constant speed switch is turned on (ON).
), FIG. 6 is a flowchart showing the control operation when constant speed control is turned off (OFF) by external throttle and pixel operation, FIG. 7 is an operation diagram, and FIG. Figure 9 is a diagram showing the relationship between vehicle speed and traction force for a direct type power line, Figure 9 is a diagram showing the relationship between vehicle speed and traction force for a torque flow type power line, and Figure 10 is a diagram showing the relationship between vehicle speed and traction force for a power line with a torque flow type. FIG. 2 is a diagram showing the relationship between vehicle speed and tractive force on a line. 1 is the engine, 2 is the governor device, 3 is the controller, 4
is the dexel, 5 is the external throttle, and 6 is the transmission. Applicant Komatsu Manufacturing Co., Ltd. Representative Patent Attorney Masaaki Yonehara

Claims (1)

[Claims] It has an engine governor device, a constant speed switch operation processing unit, a setting unit for setting initial values of output rotation speed, fuel control amount, and vehicle speed, a constant speed control unit, a control release command unit, and an external throttle priority unit. 1. A vehicle speed control device for a tracked vehicle, comprising: a controller that controls the governor device to keep the vehicle speed constant by storing the current vehicle speed by pressing a constant speed switch.