JP2008057390A5 - - Google Patents

Description

Engine control device for work vehicle

  The present invention relates to an engine control device that controls the rotational speed of an engine mounted on a work vehicle such as a tractor or a passenger management machine.

In a work vehicle such as a tractor, control is performed such that an engine speed suitable for a high load during work is set and the idling speed is restored when the work is interrupted. For example, when a tractor equipped with a cultivator is provided with a sensor that detects the raising and lowering of the cultivator, and when the cultivator is lowered to the ground, the engine rotation is set to a predetermined high rotation as the working state and the cultivator is raised. The engine rotation is set to idling rotation.
Japanese Patent No. 2904854 Japanese Patent No. 3348391

  In the technique described in the above-mentioned patent document, in order to make the engine speed idling, the cultivator must be raised. Therefore, when the operation is interrupted while the cultivator is grounded, the engine rotation is manually performed. Must be reduced.

  Accordingly, an object of the present invention is to easily cancel the automatic control of the engine rotation as necessary and switch to the rotation control by the accelerator pedal.

The above object of the present invention is achieved by the following configuration.
That is, in the first aspect of the invention, the accelerator operating means 1 for changing the engine speed continuously from idling to the maximum speed, and an engine speed different from the accelerator operating means 1 is set to a predetermined speed. The engine speed setting switch 2 is provided. When the clutch pedal 3 is turned off, the engine speed control is performed by the accelerator operating means 1 and when the clutch pedal 3 is turned on, the engine speed setting switch 2 is set. This is an engine control device for a work vehicle that is required to be controlled in the first place.

  The engine control of the work vehicle according to claim 1, wherein the engine speed setting switch 2 can be set to a plurality of set speeds or a stepless set speed. It is a device.

According to a third aspect of the present invention, the execution of the engine speed control by the accelerator operating means 1 when the power is turned off by the clutch pedal 3 is performed when the engine speed is lower than the set speed by the engine speed setting switch 2. The engine control device for a work vehicle according to claim 1, wherein the engine control device is configured as described above.
According to the fourth aspect of the present invention, the accelerator memory switch 19 for performing engine speed setting control by the engine speed setting switch 2 for setting the engine speed to a predetermined speed is provided, and when the accelerator memory switch 19 is ON, the engine is set. The engine control device of the working vehicle is configured to perform the rotation speed setting control and to perform the engine rotation speed control by the accelerator operation means 1 when the accelerator memory switch 19 is OFF.

The effect by the said structure is as follows.
In the configuration of the first aspect, when the work vehicle is running and the work is performed, the engine is rotated at a high speed suitable for the work by the engine speed setting switch 2. When this operation is interrupted, if the clutch pedal 3 is depressed to perform a power-off operation, the engine speed is shifted to control by the accelerator operating means 1 and is usually reduced to the idling speed. Further, when the clutch pedal 3 is returned and the power-on operation is performed, the engine speed returns to the set speed of the engine speed setting switch 2 so that the operation can be started at a predetermined high speed.

  In this way, the engine speed can be controlled only by operating the clutch pedal 3, and the speed can be quickly reduced from the work speed to the speed at which the work is interrupted, or conversely from the low speed speed at which the work is interrupted to the high speed at the start of the work. You can go up.

  In the configuration of claim 2, by enabling the engine speed setting switch 2 to be set to a plurality of set speeds or stepless set speeds, for example, work such as tillage work or weeding work on a field by a tillage device The engine speed can be set according to conditions.

In the configuration of claim 3, when the engine speed control in the accelerator operating means 1 during the power-off operation by the clutch pedal 3 is lower than the set speed by the engine speed setting switch 2, When the accelerator operating means 1 is at a high speed, if the clutch pedal 3 is depressed, the risk of suddenly high engine speed is prevented.
In the configuration of the fourth aspect, the automatic control of the engine rotation can be easily canceled and switched to the rotation control by the accelerator pedal as the accelerator operation means 1.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing input / output of a control signal. The movement of an accelerator pedal is detected, and the amount of depression is sent to a central processing circuit (CPU) 6 via an input circuit 5 by an accelerator sensor, that is, an accelerator operating means 1. The set rotational speed is sent to the CPU 6 via the input circuit 5 from the rotational speed setting switch 2 that appropriately sets the rotational speed of the engine from the idling rotational speed to the maximum rotational speed. The rotation speed setting switch 2 can set a plurality of rotation speeds or an arbitrary rotation speed.

  The movement of the clutch pedal 3 is detected by a clutch pedal sensor 9 that reads the rotation angle of the clutch pedal 3 with a potentiometer and a clutch pedal switch 10 that detects the depression of the clutch pedal 3, as shown in FIG. The data is sent to the CPU 6 via the input circuit 5. The clutch pedal 3 is used to turn on and off the running clutch and the PTO clutch, and sequentially turns on and off the running clutch and the PTO clutch as shown in FIG. 5 according to the depression angle of the depression stroke. That is, the figure shows the depression position from the left to the right as a numerical value. First, when the depression starts, the clutch pedal sensor 9 first determines the engine rotation as the “OFF1” position at the numerical value 298, and further depresses it a little. When the numerical value 364 is reached, the clutch pedal sensor 9 is set to “OFF2” and the PTO clutch is disengaged. When the numerical value 378 is reached, the clutch pedal switch 10 reacts and the traveling clutch is disengaged. A numerical value 794 is a position where the sensor 3 of the clutch pedal 3 is released.

  The signal of the clutch pedal sensor 9 is an analog signal, the signal of the clutch pedal switch 10 is a digital signal, and the signal determination position can be easily adjusted by changing the type of the input signal.

  When the clutch pedal 3 is returned from being depressed, the engine speed is restored by turning off the clutch pedal switch 10, the PTO clutch is engaged when the clutch pedal sensor 9 is "OFF2", and the traveling clutch is engaged when "OFF1". Work resumes smoothly by operating. In this work return, if “OFF2” and “OFF1” are brought close to each other so that the engagement operation of the traveling clutch is performed following the engagement operation of the PTO clutch, the operation becomes smooth without a sense of incongruity.

Further, if the clutch pedal switch 10 senses that the clutch is disengaged, the traveling clutch is disengaged, so that the engine can be started.
An on / off signal is sent to the CPU 6 via the input circuit 5 from the PTO switch 11 which performs power interruption of the PTO shaft which drives the work machine.

  In addition, when the left and right brake pedals are depressed simultaneously, the left and right wheels and crawlers are braked to stop traveling, and the on / off signal is input from both brake sensors 12 that detect the depression of both brake pedals and send signals. This is sent to the CPU 6 via the circuit 5.

Further, the accelerator memory switch 19 is a switch that determines whether or not to perform engine speed setting control by the speed setting switch 2.
Inside the controller 17, a CPU 6 connected to the input circuit 5 and the output circuit 18 is provided, and a timer 7 for measuring the passage of time and an accelerator memory 8 for storing the set engine speed are provided in the CPU 6.

  A control signal from the CPU 6 is sent from the output circuit 18 to the CAN data 13 at the set rotational speed of the engine 14, and the fuel injection amount at the electronic governor of the engine 14 is controlled so that the engine rotates at the engine rotational speed of the CAN data. Is done.

Further, an on / off control signal is output from the output circuit 18 to the traveling clutch 15 and the PTO clutch 16.
Next, the state of engine speed control will be described with reference to FIGS.

  First, in step S1, signals from sensors and switches provided on the signal input side of FIG. 1 are read. In step S2, it is determined whether the engine speed is stored in the accelerator memory 8. If stored, the accelerator in step S3 is determined. The process proceeds to a determination as to whether the memory switch 19 has been switched from ON to OFF. If YES, the accelerator memory 8 in step S5 is unset and the stored rotational speed is erased.

  If the rotational speed is not stored in step S2, the process proceeds to step S4 to determine whether the accelerator memory switch 19 has been switched from OFF to ON. If YES, the accelerator memory 8 can be set, that is, stored in step S6. . If the determination in step S3 and step S4 is NO, the process proceeds to the determination in step S7 for another accelerator memory set.

  Here, when the accelerator memory switch 19 is ON, the engine speed setting control by the engine speed setting switch 2 is enabled. When the accelerator memory switch 19 is turned OFF, the engine speed control is performed solely by the accelerator pedal.

  If the determination in the accelerator memory set in step S7 is NO, if NO, the instruction rotational speed of the accelerator sensor 1 is stored in the CAN data 13 as the engine rotational instruction rotational speed in step S9, and thereafter the engine speed is controlled by the accelerator pedal. This state is used when the work vehicle is only traveling.

  If YES in step S7, the set rotational speed stored in the accelerator memory 8 in step S8 is set in the CAN data 13 as the designated rotational speed of the engine 14, and the rotational speed of the engine 14 is set to the rotational speed. And the process proceeds to step S10.

  If YES in step S10, if the clutch pedal sensor 9 is determined to be “OFF”, first, the travel clutch in step S12 is disengaged by depressing to the OFF1 position (see FIG. 5) of step S11, and further depressing to OFF2 of step S13. If so, the PTO clutch in step S14 is disengaged. Thus, the work is smoothly interrupted by disengaging the PTO clutch after disengaging the traveling clutch.

  After that, the accelerator memory 8 is read out in step S15, and if the indicated rotational speed in the accelerator sensor 1 is lower than the engine rotational speed stored in the accelerator memory 8 in step S16, the indicated rotational speed of the accelerator sensor 1 in step S17 is obtained as CAN data 13 If the engine speed indicated by the accelerator sensor 1 is equal to or greater than the engine speed stored in the accelerator memory 8, the process proceeds to step S24. The comparison between the indicated rotational speed at the accelerator sensor 1 and the engine rotational speed stored in the accelerator memory 8 is for preventing the engine from rotating at a high speed as the indicated rotational speed at the accelerator sensor 1 increases.

  If NO in step S10, the process proceeds to step S18 where there is an on / off operation. If YES, step S19 determines whether the clutch pedal sensor 9 is loosened to the OFF2 position. If YES, in step S20, the rotational speed of the accelerator memory 8 is set in the CAN data, the rotation of the engine 14 is returned to the working rotational speed, the PTO clutch is engaged, and the clutch pedal sensor 9 in step S21 is further operated. If it is determined that the stepping back to the OFF1 position is returned, and the answer is YES, the travel clutch is engaged in step S22, and the travel starts after the work implement reaches the work rotational speed. If no, the process proceeds to step S24.

  In step S24, it is determined whether the PTO switch 11 has been switched from on to off. If YES, the PTO clutch is disengaged and the timer count is started in step S25. In step S26, the working machine waits for the elapse of a predetermined time. Is stopped, it is determined in step S27 whether the indicated rotational speed of the accelerator sensor 1 is equal to or lower than the rotational speed of the accelerator memory 8. If YES, the indicated rotational speed of the accelerator sensor 1 is set in the CAN data 13 in step S28. Then, the rotation of the engine 14 is reduced. If NO, the process proceeds to step S33.

  If the determination in step S24 is NO, it is determined whether the PTO switch 11 in step S29 has been switched from OFF to ON. If YES, the rotational speed of the accelerator memory 8 in step S30 is set in the CAN data 13 and the engine. 14 is increased and the timer count is started. If the engine 14 reaches the working speed after a predetermined time has elapsed in step S31, the PTO clutch is engaged in step S32. If determination of step S29 is NO, it will transfer to step S33.

  In step S33, it is determined whether the left and right brake sensors 12 are stepped on. If YES, the PTO clutch disengagement operation is performed following the travel clutch disengagement operation in step S34, and the indicated rotational speed of the accelerator sensor 1 in step S35 is the accelerator memory. It is determined whether the engine speed is equal to or less than 8, and if YES, in step S36, the speed of the accelerator sensor 1 is set in the CAN data 13 to decrease the engine speed. If NO, the process proceeds to the next control.

  If the determination in step S33 is NO, the both brake release operation in step S37, that is, the brake release determination is performed. If YES, the rotation speed of the accelerator memory 8 is set in the CAN data 13 in step S38 to increase the rotation of the engine 14. Then, the traveling clutch engagement operation is performed following the PTO clutch engagement operation.

If the determination in step S37 is NO, the process proceeds to the next control as it is.
In the above engine control, the rotational speed of the engine 14 is controlled by the clutch pedal on / off operation, but the rotational speed of the engine 14 may be controlled by turning the PTO switch 11 on and off instead of the clutch pedal. good. That is, when the PTO switch 11 is turned OFF, the engine speed is controlled by the accelerator sensor 1, and when the PTO switch 11 is turned ON, the speed setting switch 2 is set.

  Further, the rotational speed of the engine 14 may be controlled by turning on and off both brake sensors 12 instead of the clutch pedal. That is, when both brake sensors 12 are turned off, the engine speed is controlled by the accelerator sensor 1, and when both brake sensors 12 are turned on, the set speed of the speed setting switch 2 is set.

When the engine speed is controlled by the PTO switch 11 or the both brake sensors 12, the engine speed is controlled by the accelerator sensor 1, and the timing of turning on and off of the traveling clutch and the PTO clutch is controlled by the clutch pedal. Just do the same.

It is a control block diagram of engine speed control. It is a control flowchart figure. It is a control flowchart figure. It is a side view of a clutch pedal. It is explanatory drawing which shows the depression position of a clutch pedal, and a control signal extraction position.

Explanation of symbols

1 Accelerator operation means (Accelerator sensor)
2 Engine speed setting switch
3 Clutch pedal
5 Input circuit
6 Central processing circuit (CPU)
7 Timer
8 Accelerator memory
9 Clutch pedal sensor
10 Clutch pedal switch
11 PTO switch
12 Both brake sensors
13 CAN data
14 engine
15 Traveling clutch
16 PTO clutch
17 Controller
18 Output circuit
19 Accelerator memory switch

Claims (4)

  Accelerator operating means (1) for steplessly changing the engine speed from idling to maximum speed, and an engine speed setting switch for setting an engine speed different from the accelerator operating means (1) to a predetermined speed ( 2), the engine speed control is performed by the accelerator operating means (1) by power-off operation by the clutch pedal (3), and the engine speed setting switch (2) is operated by power-on operation of the clutch pedal (3). An engine control device for a work vehicle that is controlled to a set rotational speed.   The engine control device for a work vehicle according to claim 1, wherein the engine speed setting switch (2) can be set to a plurality of set speeds or a stepless set speed.   The engine speed control by the accelerator operating means (1) when the power is turned off by the clutch pedal (3) is executed when the engine speed is lower than the set speed by the engine speed setting switch (2). The engine control device for a work vehicle according to claim 1, wherein the engine control device is a work vehicle. An accelerator memory switch (19) for performing engine speed setting control by an engine speed setting switch (2) for setting the engine speed to a predetermined speed is provided. When the accelerator memory switch (19) is ON, the engine speed is set. An engine control device for a work vehicle configured to perform control, and configured to perform engine speed control by an accelerator operating means (1) when the accelerator memory switch (19) is OFF.