JP3134917B2 - Tractor engine speed control - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Industrial applications] In recent years, work with agricultural tractors
Higher speeds are being promoted, and especially tilling at high speeds is possible
Tractor to ensure safety during turning
Provided technology to control engine speed to lower speed to maintain
Have been. In this way, the work machine is raised and turned
In some cases, simply lowering the engine speed is safe
Performance can be ensured, but the actual tilling work will be delayed,
In addition, the engine speed was too low,
The problem of generating a load state occurs.
The present invention does not cause these problems, and
The speed must be reduced to high speed to ensure safety.
You.

[0002]

2. Description of the Related Art In recent years, as the number of agricultural tractors capable of tilling at a high speed increases, it has been found that a control mechanism for reducing the engine speed is provided in order to ensure safety during turning. Became. For example, Japanese Unexamined Patent Publication
In the technology described in Japanese Patent No. 276807, turning is defined as when a rise in the work implement is detected by a sensor, and a reduction value of the engine speed is detected based on the detection of the PTO shaft speed and the speed change lever position. And discloses a tractor having a control mechanism for reducing the engine speed during turning.

[0003]

If the structure is such that the engine speed is reduced uniformly at the time of turning, a problem occurs that the turning speed is too slow when working at low speed. Therefore, it is desirable that the engine speed reduction control at the time of turning can be selectively performed. In addition, when this selection work is repeated high-speed work and low-speed work, it becomes complicated. The control may be released according to the traveling speed during the work. Also,
The gin rotation speed is reduced by T ₁ seconds (eg,
0.5 second). Work equipment rises
To provide a time lag of T ₁ second in anticipation of
You. As a result, the engine speed
Reduce the hydraulic lift proportional to the engine speed
Of the work machine slows down and the work machine rises slowly
This problem can be solved. Also,
Even when low-speed turning control is set, it is felt that the speed during turning is too slow.
Speed can be increased by accelerator operation
So that the turning speed during control is
If the speed is slower than expected, turn the accelerator
It is a configuration that can increase the degree.

Conventionally, in the control for reducing the engine speed, the idle speed (maximum speed in the idle state) is used as a reference, and all of the engine speed is set at a certain rate with respect to the accelerator setting speed. Reduced the engine speed. Therefore, above the idle speed, the higher the accelerator setting speed, the greater the reduction in engine speed. However, with this configuration, when the accelerator rotation speed is high, when the turning is completed and the engine rotation speed is returned to the accelerator rotation speed during straight running, the reduction in the engine rotation speed is large. It does not easily return to the rotation speed and does not easily start running at the speed that the operator thinks. That is, there was a problem in running feeling. This point is assumed when the engine speed is the same as the accelerator speed.
Set the reference for the accelerator setting rotation speed, and
When the work equipment rises with the switch ON, the accelerator setting rotation
When the number is higher, it is constant with the accelerator setting speed.
The engine speed is reduced by the ratio of
Is solved by making the engine rotation speed and the accelerator setting rotation speed the same .

[0005] Further, in a tractor capable of selecting a control for reducing the engine speed in accordance with the rise of the work machine, when the work machine is raised and steered after the work with the control selected is completed. If the machine is raised, it is regarded as a turn and the engine speed, which had been reduced when the work machine was raised, is released, but the control is suddenly returned to the original speed, so the engine speed has already been increased. If the control is released, the vehicle suddenly starts and is dangerous. Means to avoid this danger are desired. At this point, turn off the low-speed turning setting switch.
The engine speed is still above a certain level
Low-speed driving control state until the rotation speed falls below
That the control is not released and the control is not released
This has been solved by displaying with .

Further, the low-speed turning setting switch is turned on.
When the accelerator speed is less than a certain
Speed is less than a certain percentage of the accelerator speed.
If the lowering condition persists for a certain period of time,
In order to notify the engine overload,
Flashing low-speed turning mode display lamp lit at N
When the engine is overloaded, that is, when the actual engine speed is significantly lower than the engine speed set by the accelerator, a means for displaying this is provided to alert the operator. It is.

[0007]

The present invention uses the following means to solve the above problems. According to the first aspect, the engine speed is increased when the work implement is lifted.
A low-speed turning setting switch to perform control to reduce
Control by turning ON / OFF the low-speed turning setting switch
Tractor with low-speed turning setting
When the switch is turned ON, the reduction of the engine speed ER
Providing a time lag of T ₁ seconds from the rising start of operation of the working machine,
Further, when the engine speed is reduced by the control,
When the accelerator is operated, the engine speed will
It returns to the constant rotation speed .

[0008] In the second aspect, at the time of raising the work machine,
Low-speed turning setting for performing control to reduce engine speed
Switch, and ON / OF of the low-speed turning setting switch
In the tractor where the control can be selected in F,
The engine speed is the same as the accelerator speed.
Set the standard for the set rotation speed, and
When the work implement rises as N, the accelerator rotation speed
At the time of the above, a fixed ratio to the accelerator setting
To reduce the engine speed,
The rotation speed is set to the same as the accelerator setting rotation speed .

According to a third aspect of the present invention, when the work implement is lifted,
Low-speed turning setting for performing control to reduce engine speed
Switch, and ON / OF of the low-speed turning setting switch
In the tractor where the control can be selected in F,
After turning off the speed turning setting switch, the engine
If the rotation speed is higher than a certain value, the rotation speed
Do not release the low-speed traveling control state until the
The fact that it is not divided is displayed on the display device .

According to a fourth aspect of the present invention, when the work implement is lifted,
Low-speed turning setting for performing control to reduce engine speed
Switch, and ON / OF of the low-speed turning setting switch
In the tractor, the control of which can be selected at F,
When the low-speed turning setting switch is turned on, the accelerator
The engine speed is lower than a certain value and the engine speed is accelerator
At a certain rate or less with respect to the set rotation speed
If the engine continues for a certain period of time,
To turn on the low-speed turning setting switch, turn on the low-speed
The turning mode display lamp blinks .

[0011]

[Function] An engine speed reduction control when the working machine is lifted can be selected by a low-speed turning setting switch. When the vehicle is running at a low speed that does not require control, the control is not selected, so that the operation can be performed at an extremely low speed even when turning. Can be. Also,
The gin rotation speed ER is reduced by T ₁ second (eg
(For example, 0.5 seconds). Work machine is up
In anticipation after raising, those in which a tie Muragu of T ₁ seconds
It is. This allows the engine to be turned
When the number of revolutions ER is reduced, it is proportional to the engine speed ER.
The lifting speed of the hydraulic lift L slows down and the work machine rises.
Can be fixed.
It is. Further, if the accelerator is operated during the engine reduction control, the engine speed is returned to the accelerator set speed, so that if the speed at the time of turning is too slow, the speed can be increased by operating the accelerator.

Further, the engine speed is reduced at a fixed rate of the accelerator speed only when the speed is equal to or higher than the reference accelerator speed, so that the engine speed can be reduced even at the accelerator speed higher than the reference speed. The width is reduced, and the speed return time after turning is reduced.

Further, by adopting a configuration in which the control for reducing the engine speed is not released unless the engine speed is set to a certain value or less, it is possible to avoid a situation in which the control is released and the vehicle starts suddenly at the time of high-speed operation after the work is completed. Further, the display does not disappear unless the control is released, and it can be known that the control is not released.

Further, when the accelerator setting speed is equal to or higher than a predetermined value, and when the accelerator setting speed is lower than the predetermined value, the state in which the engine speed is less than or equal to a predetermined ratio with respect to the accelerator setting speed which is considered to be an engine overload is maintained for a certain period. Within
By not blinking the lamp that indicates engine overload, it is possible to avoid the situation where the lamp blinks even when the overload state can be escaped without performing accelerator operation, etc. The lamp will blink only when the engine is overloaded.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of the present invention will be described below with reference to the embodiments shown in the accompanying drawings. FIG. 1 is a plan view of a tractor, FIG. 2 is a plan view of a switch panel 5 disposed on a side of a seat, FIG. 3 is a front view of an instrument panel 2 disposed in front of the seat,
FIG. 4 is a system block diagram of the engine control of the present invention, FIG. 5 is a control flowchart for reducing the engine speed at the time of turning and reversing, and FIG. 6 is a graph showing the amount of reduction of the engine speed at the time of setting the low speed turning. (A) shows a conventional engine rotation speed reduction control structure, (B) shows a control structure of (A), and shows a return mode of the engine rotation speed after turning when the accelerator setting rotation speed X is reached, (C) ) Shows the engine speed reduction control structure of the present invention, and FIG.
(C) Accelerator setting rotational speed R serving as a reference for control
An engine speed reduction control flowchart when 1 is set, FIG. 8 is a low-speed turning setting release flowchart,
FIG. 9 is a flowchart of the engine overload display control.

First, the structure of each switch, lever and sensor in the tractor of the present invention will be described with reference to FIG. A hydraulic lift L, which is driven up and down by hydraulic pressure, extends rearward at the rear of the tractor so that a working machine such as a rotary working machine R can be mounted. In the tractor, the bonnet 1 is arranged at the front, and in it,
The engine E is mounted, and a fuel injection pump P for the engine E is attached to the engine E. The fuel injection pump P is provided with a rack position sensor for detecting a fuel injection amount. At the forefront of the hood 1, an engine control controller EC that controls the engine speed based on the operation of a low-speed turning setting switch SW1 and the like described later is provided.

An instrument panel 2 is provided at the rear of the hood 1 so that an operator sitting on a seat 4 can visually recognize the front face. A handle 3 is protruded immediately behind the instrument panel 2, and, beside the instrument panel 2,
Accelerator lever AL for controlling engine speed
And a reversing lever RL, which is a forward / reverse switching operation lever, is protruded. An accelerator sensor AS for detecting the lever setting position of the accelerator lever AL is provided in the hood 1, and a low-speed reverse setting switch SW6 that is turned on when the reverser lever RL is switched to the reverse position is provided. When the work implement is raised during reverse movement by turning on the low-speed reverse setting switch SW6, the engine speed is reduced.

On the side of the seat 4, levers such as a main shift lever and an auxiliary shift lever are provided, and a hydraulic lift control controller LC for controlling the lifting and lowering of the hydraulic lift L is provided inside. ing. Further, a switch panel 5 is provided near the outer fender. The switch panel 5 is provided with various switches. FIG.
First, an elevating switch SW1 for raising and lowering the hydraulic lift L is provided at the forefront. When the lift switch SW1 is slid forward, the hydraulic lift L
There lowered, has a configuration that rises to slide backwards. A backup switch SW2, a low-speed turning setting switch SW3, a turning speed changeover switch SW4, and a one-touch raising / lowering on / off switch SW5 are provided from the front through the armrest 5a.

When the backup switch SW2 is turned on, the hydraulic lift L rises when the vehicle is moving backward, that is, when the reverse lever RL is operated backward. When the low-speed turning setting switch SW3 is turned on, control for reducing the engine speed is performed when the hydraulic lift L rises (controlled by the engine control controller EC). This switch is used to switch the traveling speed when the work machine is lifted to three stages of low speed, medium speed, and high speed. When the one-touch up / down on / off switch SW5 is turned on,
When the lifting switch SW1 is raised or lowered, the hydraulic lift L is raised or lowered to the end even if the hand is released. (When the one-touch up / down on / off switch SW5 is OFF, the hydraulic lift L goes up or down by an amount corresponding to the sliding operation of the up / down switch SW1.)

As shown in FIG. 3, when the low-speed turning setting switch SW3 of the switch panel 5 is turned on, the instrument panel 2 is under low-speed turning control, that is, control for reducing the engine speed during turning. A low-speed turning mode display lamp 6 is provided to indicate the fact.

In the tractor having the above configuration,
The overall structure of the engine control will be described with reference to FIG. Said
As an input means of the engine control controller EC,
Down switch SW1, low speed turning setting switch SW3, turning
Speed change switch SW4 and low speed reverse setting switch S
W6, ON / OFF switching or turning speed off
The changeover switch SW4 has three stages: high speed, medium speed, and low speed.
Input the gearshift input signal to the engine controller.
Power. Further, as an input detecting means, an accelerator lever is used.
-Accelerator sensor AS that detects the set position of AL
Rack position sensor to detect engine output status, rotation
Sensors and various other sensors.
The output value is input to the engine controller EC.

Based on these input means, the output value of the speed control solenoid or the speed control motor is calculated in the engine control controller EC, and the output value is driven to control the engine speed. is there. Under the ON / OFF of the low-speed turning setting switch SW3 and other constant conditions, the turning mode display lamp 6 on the instrument panel 2 is turned on, off, or blinks.

The control mechanism of the engine speed as described above
The flow of the engine speed reduction control will now be described with reference to the flowchart of FIG.
This is explained in the chart. First, the engine rotation during turning
If the control to reduce the number ER is performed during low-speed work, the turning speed
Because it is too slow
Only when the setting switch SW3 is turned on,
The control for reducing the rotation speed ER is performed. One
That is, the low-speed turning setting switch SW3 is turned off.
When turning, the turning speed is as set by the accelerator lever AL
become. When the low-speed turning setting switch SW3 is ON,
Turns on the built-in lamp of the low-speed turning setting switch SW3
And the low-speed turning setting display label on the instrument panel 2.
The lamp 6 lights up.
It is lit. Note that the low-speed turning setting switch SW3 is turned off.
Release of low-speed turning control at F and when holding OFF
Will be described later with reference to FIG.

When the low-speed turning setting switch SW3 is ON, the turning judgment is regarded as when the work implement is raised, and the engine speed E is increased when the raising / lowering switch SW1 is raised.
Reduce R. Note that the engine speed ER is reduced after T ₁ second (for example, 0.5 second) from the start of the ascent operation. This is because if the engine speed ER is reduced at the same time as the start of the ascent operation, the rising speed of the hydraulic lift L, which is proportional to the engine speed ER, becomes slower, and the working machine rises later. in anticipation after rising, it is provided with a time lag of T ₁ seconds. When the tilling operation is started again after turning, the raising / lowering switch SW1 is lowered. With this lowering operation, the engine rotation speed ER returns to the set rotation speed of the accelerator lever AL (accelerator set rotation speed AR). Move to driving. In this case, without providing a time lag, the number of rotations is increased at the same time as the descending operation, and the number of rotations is quickly returned to avoid engine stall.

During the turn, the turning speed is
It is configured to avoid excessive delay. Toes
And the operator performs high-speed work before entering the work.
The low-speed turning setting switch to reduce the turning speed.
Even if the switch SW3 is ON, it is actually low during work.
Work may continue at speed, and turning at that speed
When entering, the turning speed becomes extremely slow
Therefore, it is necessary to cancel the engine speed reduction control.
Therefore, first, in the flowchart of FIG.
The rotation setting switch SW3 is ON and the engine speed
During the reduction control, if the accelerator lever AL is operated,
Speed (accelerator speed AR)
The configuration is such that the actual engine speed ER is restored.

As described above, the engine speed is reduced at the time of turning, but in addition, the engine speed ER can be reduced even at the time of reverse which is dangerous at high speed. That is, as described above, the reverser lever RL
Is switched to the reverse position, the low-speed reverse setting switch SW
6 is turned on, and the engine speed ER is reduced after T ₁ second (for example, 0.5 second). The time lag in this case is because when the reverse switch RL is operated backward while the backup switch SW2 is ON, the hydraulic lift L rises, and for the same reason as the time lag after the operation of the lifting switch SW1 is started. This is the setting.

In the flowchart of FIG. 5,
Only when the low-speed turning setting switch SW3 is turned on, the engine rotation speed reduction control at the time of reverse travel is performed.
3 is assumed to be OFF, and it is not necessary to reduce the reverse speed during low-speed work.
In order to always reduce the engine speed during reverse travel,
Regardless of whether the low-speed turning setting switch SW3 is ON or OFF, the engine speed may be reduced when the low-speed reverse setting switch SW6 is ON.

Next, the accelerator operability during turning is improved.
The control mechanism for the above will be described with reference to FIGS.
You. The engine speed ER in a straight line is the accelerator setting
Matches the number AR. On the other hand, when turning, conventionally,
As shown in FIG. 6A, the idling speed (idling state
Of the engine speed ER and the engine speed ER
Set the accelerator rotation speed AR to match and set the accelerator
When the constant rotation speed AR is higher, the accelerator setting rotation speed
Revolving speed while making the engine speed ER proportional to AR
Setting of the speed changeover switch SW4 (high speed H, middle speed M, low speed
L), a fixed percentage is set for the accelerator setting rotational speed AR.
The total was reduced.

However, at the time of turning, it is generally to keep the position of the accelerator lever AL when the vehicle is traveling in a straight line or to lower the position slightly to a lower speed. It will not be dropped. In this state, when the engine speed is restored again at the end of the turn, although the accelerator lever AL is depressed, the engine speed ER suddenly reaches the set speed AR.
However, there is a problem in running feeling that the vehicle does not run at the speed as desired. To explain with reference to FIG. 6 (B), after the end of the turn, the operator sets the accelerator lever AL to the accelerator setting rotation speed X of the medium speed in order to obtain the desired speed. It takes time to recover the engine speed ER. When the turn is completed, it is desirable to start running at a speed close to the speed corresponding to the set position of the accelerator as soon as possible.

Therefore, as shown in FIG.
At the accelerator setting rotation speed AR higher than the number IR,
Approximate workers are set when starting a straight run after finishing
When turning (reverse) to correspond to the accelerator lever AL
The same applies to the case of low speed running and straight running.
Match point R of gin rotation speed₁(For example, 1500 rpm
m), as shown in the flowchart of FIG.
When turning while the set rotation speed AR is low, a straight line
As in the case of traveling, the engine speed ER
In order to be the number of turns AR, that is, not to slow down,
The accelerator setting rotation speed AR is R₁ Turn in the above case (after
The speed will be reduced only when the vehicle starts running. This
Then, the accelerator setting rotation speed AR becomes R₁In the above condition
Even when turning, the accelerator of the engine speed ER
The reduction rate for the set rotation speed AR is small
After the turn (reverse), the engine speed will return
And the operation feeling is improved. The engine rotation
In the state where the number ER is low, the speed at the time of turning is higher than that at the time of straight running.
Even if you do not drop it, safety can be secured.
The reference point R for low-speed control when turning or reversing₁ Determined
No problem.

Next, the release of the low-speed turning setting will be described with reference to FIG.
A more detailed description will be given. Run on the road when all tilling work is completed
In order to shift to the line, raise the hydraulic lift L and
Raised, and low when turning on the road.
Since it is inconvenient to increase the speed, the low-speed turning setting switch SW
3 is turned off to cancel the low-speed turning setting. But oil
When the pressure lift L is increased, the engine speed E is increased.
R has been reduced, and in this state the low-speed turning setting switch
When SW3 is turned off, the engine speed suddenly changes during straight running.
Return to the number, and if you have already
If you have a sudden start, it is very dangerous. This danger
To avoid the problem, set the low-speed turning setting switch SW3 to
When the engine speed ER at the time of turning off is more than a certain
Low-speed driving until the rotation speed drops below that
It is better not to do it.

Therefore, first, when traveling straight (when the hydraulic lift is lifted)
The engine speed NMEM at the time of
It is stored in the roller EC. And the engine
When the rotation speed ER is smaller than the accelerator setting rotation speed AR
(When the engine is in a decelerating state)
That is to be done. In this case,
If the constant switch SW3 is ON, of course, when turning
Low speed running is maintained. And when low speed control
When the low-speed turning setting switch SW3 is turned off,
First, run straight at the set position of the accelerator lever AL at that time.
Engine speed N obtained when returning to the line_SET(That is, low
Accelerator setting times when speed turning setting switch SW3 is OFF
And the engine speed N described above._MEMComparison with
This is performed by the engine control controller EC. If N
_SET≤N_MEMThen, when the engine speed is restored
In addition, since the speed becomes lower than the speed just before turning,
There is no impression that the speed has increased rapidly,
In this case, low
Release the high-speed turning setting and also turn off the low-speed turning mode display lamp 6.
Light up.

If the low speed turning setting switch SE3 is set to O
FF_SET> N_MEMThen the engine speed
When you return, the speed will be faster than just before turning
So, for workers, the speed is faster than expected,
It is dangerous. Therefore, in this case,
Without releasing the setting, of course, the low-speed turning mode display lamp 6
It remains lit. However, the speed when traveling straight
In the case of low speed, N_MEMVery few in this place
If N_SET> N_MEMBut N_SETIs small,
Even if the rotation speed is restored, it returns to low speed,
Sex can be maintained. So N_SET> N_{ME M}But N_SET
Is below a certain level, for example, near the idle speed,
Release the turning setting and return the engine to the low-speed turning mode.
The display lamp 6 is also turned off.

Finally, engine overload during low-speed turning
The control of the load display will be described with reference to FIG. Low-speed turning
Fixed (low-speed turning setting switch SW3 is ON)
At the time of turning, a certain percentage of the accelerator setting rotation speed AR
Although the actual engine speed ER has been reduced by
Excessive speed results in engine overload and engine
It has a bad effect on gin etc. Therefore, when setting low-speed turning
Turn on the low-speed turning setting display lamp 6
The load condition, that is, the access to the actual engine speed ER
The deceleration ratio for the set rotation speed AR is below a certain
In other words, AR ≦ n × AR (for example, n = 0.7
In 2), it blinks to indicate the engine overload.
You.

However, if you make this function too sensitive,
The road is temporarily overloaded due to irregularities on the road,
Slow turning even when leaving the state immediately after running
The setting display lamp 6 flashes, and it is visually troublesome.
No. Also, operate the accelerator lever AL to the high-speed rotation side
When trying to accelerate suddenly or operate the gear shift lever to a high gear
In this case, the actual engine speed E at the start of acceleration
R is considerably lower than the accelerator rotation speed AR, but gradually
It accelerates and the engine overload condition comes out. In this case
Also blinks the lamp, visually annoying to the worker,
It also gives misunderstandings.

Therefore, assuming sudden acceleration and high speed switching,
When the accelerator setting rotational speed AR is higher than a certain reference rotational speed R2 (for example, 2300 rpm), otherwise, the engine speed ER is less than or equal to the accelerator setting rotational speed AR as a reference for the overload state. State (ie, ER ≦ n × AR) for a fixed time T
If it is less than ₂ seconds (for example, 0.5 seconds), the low-speed turning setting display lamp 6 does not blink.

[0037]

The present invention is configured as described above.
The following effects are obtained. With this configuration, it is possible to select that low-speed turning control is not performed during low-speed work and low-speed turning control is performed only during high-speed work, thereby avoiding a situation in which the user must turn at an extremely low speed during low-speed work. Is done. In addition, the decrease in the engine speed ER increases
Performs than after T ₁ seconds (e.g., 0.5 seconds) from the operation start
And In anticipation of the after working machine rises, T ₁ second
It has a time lag. This allows the ascent operation
If the engine speed ER is reduced simultaneously with the start,
The lifting speed of the hydraulic lift L proportional to the gin rotation speed ER is slow.
And the lifting of the work equipment is delayed
It can be eliminated. Further, even when the low-speed turning control is set, the speed can be increased by operating the accelerator when it is felt that the speed at the time of turning is too slow.

Since the present invention is configured as in claim 2, it becomes a reference.
Only when the engine speed is higher than the accelerator
Since the configuration is such that the cell rotation speed is reduced at a fixed rate,
If the cell setting rotation speed is below the reference,
The engine speed becomes equal to the accelerator
At the speed, the same turning as the straight running
The turning speed can be obtained and the turning speed becomes extremely low.
Be avoided. And, the accelerator setting speed is higher than the standard
Occasionally, the engine speed is reduced when turning.
However, when turning straight ahead after turning, the engine
Since the number of rotations returns to the accelerator setting rotation speed, operability is improved.
Up.

According to the third aspect of the present invention, for example, during high-speed operation after the end of work, the low-speed turning setting switch is turned off.
The danger of a sudden start with F is avoided. Also, the display will not disappear unless the control is released,
It is possible to know that the control has not been released.

According to the fourth aspect of the present invention, it is possible to prevent the lamp from blinking even when the overload state can be easily escaped without performing an accelerator operation or the like. The lamp flashes only when the engine is overloaded, without bothering the eyes of the operator.
In addition, erroneous operation resulting from misunderstanding will not occur.

[Brief description of the drawings]

FIG. 1 is a plan view of a tractor.

FIG. 2 is a plan view of a switch panel 5 arranged on a side of a seat.

FIG. 3 is a front view of an instrument panel 2 disposed in front of a seat.

FIG. 4 is a system block diagram of the engine control of the present invention.

FIG. 5 is a control flowchart for reducing the engine speed during turning and reverse travel.

FIGS. 6A and 6B are graphs showing the amount of reduction in the engine speed when a low-speed turning is set. FIG. 6A shows a conventional engine speed reduction control structure, and FIG. 6B shows an accelerator setting in the control structure of FIG. FIG. 3C shows a manner of restoring the engine speed after turning when the rotation speed is X. FIG. 2C shows the engine speed reduction control structure of the present invention.

7 is a engine speed reduction control flowchart in the case where the accelerator setting rotational speed R ₁ as a control reference were set as shown in FIG. 6 (C).

FIG. 8 is a flowchart of a low-speed turning setting release.

FIG. 9 is a flowchart of an engine overload display control.

[Explanation of symbols]

 ER engine speed AR accelerator setting speed E engine EC engine control controller AL accelerator lever RL reversing lever SW1 lifting switch SW3 low speed turning setting switch SW4 turning speed switching switch SW6 low speed reverse setting switch

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI F02D 29/04 F02D 29/04 G (72) Inventor Koji Furuta 1-32 Chayacho, Kita-ku, Osaka-shi, Osaka Yanmar Diesel shares In-house (56) References JP-A-2-42146 (JP, A) JP-A-6-276807 (JP, A) JP-A-1-195933 (JP, A) JP-A-6-16123 (JP, U 6) Actually open Hei 6-73349 (JP, U) Actually open Hei 3-10048 (JP, U) Actually open Hei 6-46407 (JP, U) Actually open Hei 6-13930 (JP, U) (58) Field (Int. Cl. ⁷ , DB name) F02D 29/00 F02D 29/04

Claims (4)

(57) [Claims] An engine speed is reduced when a work implement is raised.
A low-speed turning setting switch for performing control to reduce
Select this control by turning ON / OFF the low-speed turning setting switch
In a tractor that can be used, a low-speed turning setting switch
Is turned on, the reduction of the engine speed ER
A time lag of T ₁ second from the start of the ascent operation of
When the engine speed is reduced by this control,
Operating the engine, the engine speed will
Control of the tractor engine speed, which returns to the normal speed. 2. The engine speed is reduced when the work implement is raised.
A low-speed turning setting switch for performing control to reduce
Select this control by turning ON / OFF the low-speed turning setting switch
Tractors that have been able to
Accelerator speed reference that is the same as the cell speed
Work machine rises when the low-speed turning setting switch is turned ON.
At times, when the accelerator speed is higher,
Engine speed at a fixed rate
Engine speed and accelerator
Tractor engine speed control characterized by setting the same speed. 3. The engine speed is reduced when the work implement is raised.
A low-speed turning setting switch for performing control to reduce
Select this control by turning ON / OFF the low-speed turning setting switch
In a tractor that can be used, a low-speed turning setting switch
Is turned off, and the engine speed is still
In some cases, drive at low speed until the speed drops below that
Check that the control state has not been released and that the control has not been released.
Control of the engine speed of the tractor, characterized by displaying on a display device . 4. The engine speed is reduced when the work implement is raised.
A low-speed turning setting switch for performing control to reduce
Select this control by turning ON / OFF the low-speed turning setting switch
When the tractor has been turned on,
When the switch is turned ON, the set speed of the accelerator is below a certain level
And the engine speed is higher than the set speed of the accelerator.
Is below a certain percentage for more than a certain time
In case that, to tell the engine overload, slow turning set
Low-speed turning mode display run that lights when the constant switch is turned on
The engine speed control of the tractor, characterized by blinking display .