JP3425995B2 - Automatic control method of engine fuel injection pump for work vehicle - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to automatic control of an engine fuel injection pump of a traveling wheel type working vehicle such as a wheel loader.

[0002]

2. Description of the Related Art Conventionally, a fuel is used to control the engine speed in order to respond to the load when a work vehicle such as a wheel loader is running (especially uphill or downhill) and the load when working (excavation / loading).
For controlling the fuel injection pump in the accelerator pedal, the traveling frequently need to operate the accelerator pedal,
Also, full stroke depression of the accelerator pedal in order to maximize the engine output at the time of soil drilling operations, such as depressing the accelerator pedal during loading work to dump truck excavated sand to the half stroke, depression of the accelerator pedal for each work I was working with varying amounts.

[0003]

However, when excavating and loading work of a conventional work vehicle such as a wheel loader, the above-mentioned problem is encountered .
To change the engine from full rotation to half rotation ,
The operator is necessary to continue stepping on a long period of time the accelerator pedal
There is a complaint that my legs get tired, so I have to work hard
There was a problem that they were often forced to .

In order to solve the above problems, the present invention provides
Engine fuel for work vehicles such as wheel loaders that enable the operator to work without depressing the accelerator pedal
An object is to provide an automatic control method for an injection pump .

[0005]

To achieve the above object of the Invention The present invention provides an automatic control method for an engine fuel injection pump of the work vehicle, and a method for performing an engine fuel injection pump control in the order of the following steps. (A) In advance, the set engine speed during automatic control is stored, and (b) during operation, it is first determined whether the operator turned off the parking brake and the main brake, and when both are turned off, (c) Next, obtains engine speed corresponding to the depression angle of the accelerator pedal, compares the set engine speed and the storage the obtained engine speed, high or
One is selected as the target engine speed, and the fuel injection pump is automatically controlled so that the actual engine speed becomes equal to this target engine speed .

In the step (b), the parking brake and
When at least one of the main brake is on, the actual engine speed is a method of controlling the fuel injection pump to be equal to the engine rotational speed corresponding to the depression angle of the accelerator pedal. Further, in the step (a), the procedure for storing the preset engine speed at the time of automatic control in advance is as follows: (a1) First, the operator operates a predetermined setting switch to enter the "engine speed automatic setting"mode; ) Next, the operator depresses the accelerator pedal to a desired engine speed, and (a3) when the operator operates a predetermined engine speed setting switch to a memory position after reaching the desired engine speed, The engine speed may be stored as the set engine speed.

[0007]

[Operation] During excavation and loading work of a work vehicle such as a wheel loader,
The engine speed can be automatically controlled, and the engine speed desired by the operator is stored in advance in the controller as the set engine speed during automatic control, and during operation, the controller turns off the parking brake and the main brake by the operator. If both are turned off,
The engine speed corresponding to the depression angle of the accelerator pedal (in normal work, if the depression angle is zero, this engine speed becomes a low idle rotation speed), and the calculated engine speed and the memorized value are stored. Compare with the set engine speed and select the higher one to set the target engine
The actual engine speed is the target engine speed.
The fuel injection pump is automatically controlled to be equal to the number.
That is, the calculated engine speed is stored in the stored setting.
(From the foregoing, will be less than the set engine rotational speed during normal operations) constant engine speed following the time of the actual engine speed the set engine rotational speed (target engine rotational
Since the fuel injection pump is automatically controlled so as to be equal to the number of revolutions) , the operator can perform excavation and loading work only by operating the main brake pedal, the transmission lever, and the work implement lever without operating the accelerator pedal. As a result, the operator does not have to continue to depress the accelerator pedal for a long time, and fatigue can be reduced. In addition, the
Engine speed is lower than the stored engine speed
When it becomes higher, set the target engine speed to the accelerator pedal.
Switch to the engine speed according to the depression angle of the dull,
When the actual engine speed is equal to this target engine speed
The fuel injection pump is controlled so that
During operation, the operator depresses the accelerator pedal to
Engine speed higher than the set engine speed
You can This allows the engine to be used according to the size of the workload.
Since the gin rotation speed can be adjusted, workability can be improved.

The operator also turns on the parking brake.
Or when the main brake is turned on,
La's actual engine speed is the accelerator pedal depression angle
The fuel injection pump so that it becomes equal to the corresponding engine speed.
The operator controls the
With the brake on (vehicle stopped), press the accelerator pedal.
Step on the actual engine speed from low idle to the desired speed
When loading on a dump truck etc.
The work machine driving force can be finely adjusted. Also, the setting engine
When storing the engine speed, the operator
Step into the desired engine that suits each work content.
After setting the gin speed, set the engine speed at this time.
Memory work by storing as a constant engine speed
Is easy and easy, and the setting
The engine speed can be reliably stored.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the accompanying drawings. As shown in FIG. 1, a machine to which the present invention is applied
Attaches a boom 16 to a vehicle body 15 by means of a boom cylinder 17 so as to be vertically swingable, and attaches the bucket 1 to the tip of the boom 16.
8 is a wheel loader in which a bucket cylinder 19 is mounted so that tilting and dumping can be freely performed. The output of the engine 8 of the wheel loader is transmitted to the transmission 11 via the torque converter 10, and the output of the transmission 11 is transmitted via the differential gear and the final reduction gear 12 to the wheels 1.
It is transmitted to 3.

Next, the accelerator pedal potentiometer 1
When an engine speed setting switch 2, a main brake pressure sensor 3, the parking brake pressure sensor 4, a transmission lever sensor 5, each <br/> output of the working machine hydraulic pressure sensor 6 is input to the controller 7 The controller 7 controls the injection amount of the fuel injection pump 9 of the engine 8 based on the output signal of each sensor.
To control . Accelerator pedal potentiometer 1, FIG.
An accelerator pedal depression angle ( not shown) is detected , and an electric signal indicating this depression angle is input to the controller 7.

The engine speed setting switch 2 is either in the off position 2c, the on (automatic) position 2b, or the memory position 2a .
Output signal common end
The child is connected to the battery 14. Electrical signals from the switch 2 is energized off the controller 7 when the engine speed setting switch 2 in the OFF position 2c, co
The controller 7 determines that it is in the annual control mode, and determines the accelerator pedal potentiometer according to the depression angle of the accelerator pedal.
The injection amount of the fuel injection pump 9 is controlled based on the electric signal from the switch 1 . This allows
The fuel injection pump 9 is manually controlled by an accelerator pedal .

The engine speed setting switch 2 is in the ON position
(Hereinafter, referred to as automatic position) When set to 2b, the automatic control mode signal of the switch 2 is transmitted from the battery 14 to the controller 7
Is turned on, and the controller 7 judges that the automatic control mode is on.
Refuse. After this, the engine speed setting switch 2 is automatically
If you switch from position 2b to memory position 2a,
Engine corresponding to the depression angle of the accelerator pedal of
The engine speed is controlled as the set engine speed during automatic control.
It adapted to be stored in the roller 7, thereby Oh
The desired engine speed of the pelrator is equal to the automatic control target value.
Is set . The engine speed setting switch 2 is operated
Regulator is adapted to be automatically returned to the automatic position 2b Release the memory position 2a, while the operator holds the automatic position 2b, the fuel injection Pont according to the present invention
The automatic control mode of the loop continues. Well
Also, set the engine speed setting switch 2 to the off position 2c.
When you switch to, the automatic control of the fuel injection pump is canceled ,
The injection pump is manually controlled by the accelerator pedal.
It seems to be .

[0013] The main brake pressure sensor 3 detects the hydraulic pressure corresponding to the depression amount of the main brake, not shown, inputs an electric signal indicating the pressure to the controller 7. The main brake can be operated by the operator regardless of the automatic control of the fuel injection pump of the present invention. Parking brake pressure sensor 4 detects the hydraulic pressure corresponding to the operation amount of not shown parking brake, and inputs the electrical signal indicating the oil pressure to the controller 7. The parking brake is the fuel of the present invention.
It is operated by the operator regardless of the automatic control of the injection pump.
You can Transmission lever sensor 5
Detects the position of the transformer couriers <br/> Yonreba is shifted by a limit switch or the like provided for each speed stage of the transmission lever (not shown), and inputs the electrical signal indicating the shift position to the controller 7. The work machine oil pressure sensor 6 is attached to the boom cylinder 17 and the bucket cylinder 19 , detects the oil pressure (work load pressure) in the boom cylinder 17 and the bucket cylinder 19 ,
An electric signal indicating this hydraulic pressure is input to the controller 7.

[0014] Next, the automatic control of the fuel injection pump according to the present invention will be described with reference to a flowchart shown in FIGS. First, the flowchart shown in FIG. 2
More will be described. Controller 7-ene <br/> Jin rotational speed setting switch 2 determines whether the automatic position 2b in step 100, the own
When the turned position 2b, the parking brake oil in step 101
The parking brake is turned on based on the detection signal of the pressure sensor 4.
Check that the operator is
Place the accelerator pedal in the neutral position of the switch lever.
When the user depresses to the desired position, the fuel injection pump is controlled according to the depression angle of the accelerator pedal to control the engine speed to a height desired by the operator . Next, at step 102 , the engine speed setting switch 2 is automatically set to the automatic position.
2b to determine whether the memory location 2a has been switched, and make a note
If the position is not 2a, the process returns to step 100 and the memory
When switched to the position 2a, the call at step 103
The engine speed corresponding to the depression angle of the accelerator pedal at the time is stored in the controller 7 as the set engine speed .

[0015]next,Parking brake on in step 104
Judge whether or not. Parking brake offWhenIs,Step
At 105Based on the detection signal of the main brake oil pressure sensor 3
Determine whether the main brake is off. Main brake offWhen
Is,At step 106Stepping on the current accelerator pedal
The command engine speed based on the angle is aboveMemorizedConfiguration
Determine if it is below the engine speed,ConfigurationBelow engine speed
ofWhenAt step 107Actual engine speed is above
ConfigurationenginerotationIn numberTo be equalcontroller7
Is fuelJet hoop9To the electronic governor (not shown)Command,
Automatically control the injection amount. Then, return to step 104
Repeat the above process. The fuel injection pump itself
During dynamic control modeVehicle start, Stop, excavation work, loading
Work etc. is possibleBecomes

[0016] On the other hand, when the engine speed setting switch 2 is in OFF position 2c at step 100, step 10
At 9, the fuel injection amount of the injection pump 9 is changed by depressing the accelerator pedal.
Normal manual control the line of control in accordance with the actual write angle
U If the parking brake is turned on in step 104 ,
Come, when the main brake is turned on at step 105, or
Also , in step 106, an instruction is given by the accelerator pedal.
That when the engine speed is higher than the set engine rotational speed, which is the memory, the automatic control of the fuel injection pump is released, the injection pump manual control of the step 109. Then, returning to step 104, the above processing is performed.
Repeat the reason. During this manual control, normal manual
As with the manual operation, starting, stopping, excavating work,
It becomes possible to do the work.

Next, the flow chart of FIG. 3 shows the automatic control and control of the fuel injection pump explained in the flow chart of FIG.
A excavation loading work example flowchart definitive in Manual control. First, at step 108, the automatic control mode
Start. The operator drills while in this automatic control mode.
Set the transmission lever forward for work
Turn off both the parking brake and the main brake, and
It was to reduce the stepping write only the corners of the accelerator pedal (ie accession
The engine speed commanded by the cell pedal is set to the above
Controller speed is less than or equal to the engine speed).
So that the engine speed is equal to the set engine speed
The fuel injection pump 9 is automatically controlled. Then the controller
7 is the transmission lever set in step 110.
Determining whether the vehicle forward by capacitors 5, it is determined whether the working machine hydraulic pressure of the boom cylinder 17 and bucket cylinder 19 by the working machine hydraulic pressure sensor 6 at step 111 when the vehicle travels forward is specified pressure or higher. When the working machine hydraulic pressure is equal to or greater than the specified pressure is,
The controller 7 is currently performing excavation work in step 112.
Judge that there is. The end of the excavation work is determined in step 113 by whether or not the working machine hydraulic pressure is equal to or lower than a specified pressure ,
When it is larger than the specified pressure, the process returns to step 112 . When the hydraulic pressure of the work machine falls below the specified pressure , it is judged that the excavation work is completed,
Next, in step 114, the transmission lever set
The sensor 5 determines whether the vehicle is moving backward . When the vehicle is in reverse
First , the controller 7 determines that the vehicle is moving backward after excavation, and determines in step 115 whether the main brake is on. Then, the automatic control mode in step 116 when the main Purekion
The engine speed and lowered the engine speed to low idle.
After trans <br/> transmission lever is determined whether the neutral by the transmission lever sensor 5, when the transmission lever is in neutral, step 11
At 7 it is judged that the vehicle has stopped in reverse and the vehicle is stopped. In addition,
Automatic control when main brake is not on at step 115
After returning to the mode, return to step 114,
At 116, the transmission lever is in neutral
If not, the process returns to step 114.

Next , in step 118 , the controller 7 uses the transmission lever sensor 5 to determine whether the vehicle is moving forward . When the vehicle is moving forward , step 11
When the main playoff is judged at 9 and it is the main playoff
In addition to the automatic control mode, the working machine hydraulic pressure is determined whether specified pressure or more, the working machine hydraulic pressure of the loading time of the above specified pressure
Judge that it is moving forward. After this, in step 120
Automatically when the main plankion is judged by the main plankion
Release control mode to lower engine speed
With the transmission lever sensor 5
Transmission lever it is determined whether the neutral Ri,
When the transmission lever is in neutral, it is determined in step 121 that the vehicle is stopped for loading work.
While the vehicle is stopped, the operator loads the dump truck. If the vehicle is not moving forward in step 118,
When the main plankion is performed in step 119 or the working machine
When the oil pressure is lower than the specified pressure, and again in step 120
When the brake is off or the transmission lever is
If not, go to step 118
Return. After this, the completion of the loading work is done mainly in step 122.
Automatically control when main brake off
Control mode and transmission lever sensor
The vehicle is determined whether or backward by the support 5, when the vehicle is in reverse loading
Judge that the work is completed. Next, it is determined the main brake on or at step 123, as to disable the automatic control mode at step 124 when the main brake on, determines the transmission lever is either neutral, if the transmission lever is in the neutral step 125
Determines that the vehicle is stopped .

[0019] Since the structure described above, the present invention is en
Switching the gin speed setting switch to the memory position
It makes it possible to memory set engine <br/> down the rotational speed controller according to the depression angle of the accelerator pedal, set
Regular work is easy and easy. Also, when driving,
Turn off the parking brake and main brake, and
When the pedal is not depressed (that is, the accelerator pedal
The engine speed corresponding to the pedal depression angle is stored in the
The engine speed below the set engine speed)
Become a flop automatic control mode, the controller is the real engine
Make sure that the engine speed is equal to the set engine speed.
Since the fuel injection pump is controlled , the engine speed automatically
From low idle to the above set engine speed
Retained. Therefore, when excavating and loading
Does not require long-time operation of the accelerator pedal,
Key, transmission lever, work equipment lever and ski
Fatigue is reduced because you only operate the tearing
Workability can be improved.

Used at the time of automatic control as an embodiment of the present invention
Although the case where the setting work of the set engine speed is performed using the engine speed setting switch has been described , the present invention is not limited to this, and for example, the operator can set the work mode (travel, excavation, loading, etc.). The desired engine speed for each) is stored in the controller in advance, and a switch for each work mode (running, excavation, loading, etc.) is provided, and the operator can select and press this switch to perform setting work. You may do it.

[0021]

EFFECT OF THE INVENTION During excavation and loading work of a work vehicle such as a wheel loader, an actual engine speed is preset.
By automatically controlling the rotational speed, the operator may not operate the access <br/> Rupedaru, main brake pedal, the working machine lever, transmission lever, can concentrate only on the operation of the steering <br/>. Therefore, during excavation work and loading work, the operator may be fatigued even after long-term operation .
Door without, are released from the agonizing work, you can improve the work efficiency
It In addition, the operator manually controls the accelerator pedal.
You can increase the engine speed by
When the number of revolutions reaches the number of revolutions at this time,
Since it can be stored as the number of revolutions,
Engine rotation that is easy to work with and adapts to the work load
Can be set reliably to a number. Furthermore, the main brake was turned on.
By increasing the accelerator pedal depression angle.
The manual control mode with the accelerator pedal.
Therefore, the operator's desired
Engine speed and therefore engine speed
Is easy to adjust.

[Brief description of drawings]

FIG. 1 is a structural explanatory view showing an embodiment of the present invention.

FIG. 2 is a flowchart of automatic control of a fuel injection pump .

FIG. 3 is an example of an excavation and loading work flowchart in automatic control and manual control of a fuel injection pump .

[Explanation of symbols]

1 ... Accelerator pedal potentiometer, 2 ... Engine speed setting switch, 3 ... Main brake oil pressure sensor, 4 ... Parking brake oil pressure sensor, 5 ... Transmission lever sensor, 6 ... Working machine oil pressure sensor, 7 ... Controller, 8
… Engine, 9… Injection pump.

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F02D 9/00-11/10 F02D 29/00-29/06 F02D 41/00-45/00 395

Claims (3)

(57) [Claims] 1. An automatic control method for an engine fuel injection pump for a work vehicle, comprising: controlling the engine fuel injection pump in the following process sequence. (A) In advance, the set engine speed during automatic control is stored, and (b) during operation, it is first determined whether the operator turned off the parking brake and the main brake, and when both are turned off, (c) Next, obtains engine speed corresponding to the depression angle of the accelerator pedal, compares the set engine speed and the storage the obtained engine speed, high or
One is selected as the target engine speed, and the fuel injection pump is automatically controlled so that the actual engine speed becomes equal to this target engine speed . 2. The automatic control method for an engine fuel injection pump for a work vehicle according to claim 1, wherein the number of parking brakes and main brakes is small in the step (b).
When at least one of them is on, then instead of the step (c), (c1) the fuel injection pump is controlled so that the actual engine speed becomes equal to the engine speed according to the depression angle of the accelerator pedal. An automatic control method for an engine fuel injection pump of a work vehicle, comprising: 3. The automatic control method for an engine fuel injection pump for a work vehicle according to claim 1, wherein in the step (a), the preset engine rotation during automatic control is set.
The procedure for storing the number is as follows: (a1) First, the operator operates a predetermined setting switch.
To set the "engine speed automatic setting" mode, and (a2) the operator then depresses the accelerator pedal.
To the desired engine speed, and (a3) after reaching the desired engine speed, the operator
Operates the specified engine speed setting switch to the memory position.
When making, the current engine speed is set to the above engine
An automatic control method for an engine fuel injection pump of a work vehicle, characterized by storing as a rotation speed .