JPH0814260B2 - Governor drive controller - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a governor drive control device that drives a fuel injection lever of a governor that controls a fuel injection amount of a diesel engine.

[Conventional technology]

Conventionally, in construction machinery and the like, the engine speed is controlled by connecting a mechanical mechanism such as a cable or link between the throttle lever provided in the cab and the fuel injection lever of the governor mechanism of the engine. It was However, in such a mechanical connection, operability and responsiveness are poor, and recently, a fuel injection lever driving device by an electric remote operation as shown in FIG. 5 has been proposed.

In FIG. 5, the fuel control lever 2 of the governor 1 is adapted to be rotated between the fuel full position stopper 3 and the fuel cut position stopper 4, and one end of the fuel control lever 2 has a link 5 and a spring. It is connected to the river 7 connected to the rotating shaft of the governor drive motor 8 via 6.

The rotation position of the motor 8 is detected by a motor rotation position detector 9 composed of a potentiometer or the like, and the detected value is fed back to a motor rotation command, whereby the motor 8 is rotationally driven so that the difference between the two becomes zero. .

That is, the motor 8 rotates according to the motor rotation command corresponding to the engine rotation speed command value, and this rotation is transmitted to the fuel control lever 2 via the lever 7, the spring 6, and the link 5, and the engine rotation speed commanded by this The fuel control lever 2 is tilted to a position corresponding to the command value.

In this structure, the spring 6 is provided to press the fuel control lever 2 against the stoppers 3 and 4 with an appropriate pressing force without directly applying a large load to the motor 8.

[Problems to be Solved by the Invention]

By the way, in such a structure, the stoppers 3 and 4 in the governor are adapted to exert a repulsive force on the fuel control lever 2 pressed by a structure such as a built-in spring. The fuel control lever 2 cannot be held at these stopper positions unless it is pressed against the stoppers 3 and 4 by the pressing force.

However, the positions of the stoppers 3 and 4 and the repulsion mechanism are not always manufactured exactly the same due to variations in manufacturing and preparation, and there is usually some variation.

Therefore, in order to press the fuel control lever 2 against the stoppers 3 and 4 with an appropriate pressing force in consideration of these variations, it has conventionally been necessary to make the bending allowance of the spring 6 and the total length of the spring 6 large, which results in cost reduction. There was a problem in terms of design or designability.

Further, in the above-mentioned conventional device, since only the rotational position of the motor 8 is detected, when the fuel control lever 2 does not move to a target position due to twisting of the link,
There is a problem that the motor 8 overheats and the life of the motor 8 is shortened.

The present invention has been made in view of such a situation,
(EN) Provided is a governor drive control device capable of pressing a fuel control lever against a stopper with an appropriate pressing force using a spring having a small bending allowance and preventing an overload on the motor to extend the life of the motor. To aim.

[Means for solving the problem]

According to the present invention, a fuel control lever having a stopper is connected to a governor drive motor via a spring, and the governor drive control device controls the engine speed by rotationally driving the governor drive motor. Motor position detecting means for detecting a rotational position, lever position detecting means for detecting a tilted position of the fuel control lever, lever position commanding means for commanding a tilted position of the fuel control lever, the motor position detecting means, and Driving force calculating means for calculating the driving force applied to the fuel control lever based on the detection output of the lever position detecting means, pressing force setting means for presetting an optimum pressing force for the stopper, and the driving force calculating means. Calculate the calculated driving force by comparing with the setting force of the pressing force setting means When the power becomes equal to or more than the set force, a comparison unit that outputs a driving force limit signal, a first subtraction unit that takes a deviation between the command signal of the lever position command unit and the detection value of the lever position detection unit, and the first subtraction unit A deviation amplifier that amplifies the output of the subtracting means and outputs a stop signal that stops the motor when the driving force limit signal is input, and a deviation between the output of the deviation amplifier and the detection value of the motor position detecting means. Further, the motor control means for controlling the position of the governor drive motor according to this deviation is provided.

[Action]

According to this structure, when the pressing force of the fuel control lever against the stopper by the motor exceeds a predetermined value set in advance, the motor is immediately stopped. Therefore, the fuel control lever is always pressed against the stopper with the set optimum force.

〔Example〕

Hereinafter, the present invention will be described in detail according to embodiments shown in the accompanying drawings.

FIG. 1 shows a first embodiment of the present invention,
The fuel control lever 2 of the governor 1 is adapted to be rotated between a fuel full position stopper 3 and a fuel cut position stopper 4. One end of this fuel control lever 2 is a governor via a link 5 and a spring 6. It is connected to the lever 7 of the drive motor 8. The governor drive motor 8 is a DC motor.

The rotation position of the motor 8 is detected by a motor rotation position detector 9 including a potentiometer, and the detection signal Pm
Is input to the lever driving force calculator 11 and the subtraction point 12.

The lever position detector 10 detects the position of the fuel control lever 2, and is composed of, for example, a potentiometer. The detection output Ps of the lever position detector 10 is input to the lever driving force calculator 11 and the subtraction point 13.

The lever operation position setter 20 is for the operator to set and operate the position command Sr of the fuel control lever 2, and this position command signal corresponds to the command value of the engine speed. In addition, the fuel control lever 2 should
When the fuel is placed at the fuel full load position or the fuel cut position corresponding to the position of, the lever position setting device 20 sets a lever position designation signal exceeding the positions of the stoppers 3 and 4. That is, the lever position setter
In FIG. 20, when the lever 2 is positioned at the position of the stopper 3, a position further left of the position of the stopper 3 is output as a lever position designation signal, and the lever 2 is moved to the stopper 4 position.
When the position is set to, the position on the right side of the position of the stopper 4 is output as a lever position command signal.

At the subtraction point 13, the lever position command Sr set by the lever operation position setter 20 and the detection output Ps of the lever position detector 10 are input, and the subtraction point 13 is the difference between these (Sr-Ps), that is, the lever position. The deviation signal is input to the deviation amplifier 14. When the driving force limit signal TM is not input from the comparator 15, the deviation amplifier 14 outputs the motor position signal obtained by amplifying the deviation (Sr-Ps) to the subtraction point 12, and the comparator 15 outputs the driving force limit signal TM. When input, a motor position signal for stopping the motor 8 is output. The configuration for stopping the motor will be described later.

On the other hand, the lever driving force calculator 11 calculates the difference (Pm-Ps) between the detection signal Pm of the motor rotation position detector 9 and the detection output Ps of the lever position detector 10 by the spring constant K of the spring 6. Then, the driving force Tr applied to the fuel control lever 2
And the calculated value Tr (= K (Pm-Ps)) is input to the comparator 15.

The lever driving force setting devices 16 and 17 press the fuel full position stopper 3 and the fuel cut position stopper 4, respectively.
Tr1 and Tr2 are set, and these setting forces are input to the switch 18. The switching device 18 uses the two set values Tr in accordance with the motor drive direction signal output from the output unit 19.
Select and output either 1 or Tr2. The setting force selectively output from the switching device 18 is input to the comparator 15.

The comparator 15 compares the driving force signal Tr (= K (Pm-Ps)) input from the lever driving force calculator 11 with one of the torque setting values Tr1 or Tr2 selected by the switcher 18,
When the torque setting value Tr1 or Tr2 becomes equal to or higher than the driving force signal Tr, the driving force limit signal TM is input to the deviation amplifier 14.

The deviation amplifier 14 outputs a motor position signal for stopping the motor 8 when the driving force limit signal TM is input as described above. Specific examples thereof are shown in FIGS. 2 (a) and 2 (b).

In the example of FIG. 2 (a), when the driving force limit signal TM is input, the motor position signal is set to zero (origin) by switching the switch circuit 21 to the b side, thereby inputting the reverse rotation command to the motor 8. To do. As a result, the motor 8 is moved back and forth due to inertia, and then the motor 8 is finally stopped.

In the example of FIG. 2B, when the driving force limit signal TM is input, the contact of the switch circuit 22 is turned off,
At this time, the same motor position signal as the previous time stored in the capacitor 23 is output to stop the motor 8.

In either case, the deviation amplifier 14 outputs a motor position signal for stopping the motor 8 when the driving force limit signal TM is input.

The subtraction point 12 takes the deviation between the motor position signal input from the deviation amplifier 14 and the motor rotation position detection signal Pm detected by the motor rotation position detector 9, and inputs it to the signal output unit 19. The signal output unit 19 rotationally drives the motor 8 according to the motor position deviation signal input from the subtraction point 12, determines the current motor rotation direction from the polarity of the motor position deviation signal, and sends this determination signal to the switcher 18. By inputting, the switching device 18 is switched and controlled. That is, when the motor 8 is rotating to the speed increasing side, the signal output unit 19 selects the pressing torque Tr1 to the fuel full position stopper 3 set in the torque setting device 16, and the motor 8 is rotating to the decelerating side. When it is, the switching control signal for selecting the pressing torque Tr2 for the fuel cut position stopper 4 set in the torque setting device 17 is output to the switching device 18.

In such a configuration, when the fuel control lever 2 is in a normal state where it does not hit any of the stoppers 3 and 4, the detection signal Ps of the lever position detector 10 and the detection signal Pm of the motor rotation position detector 9 match. The fuel control lever 2 is positioned as instructed by the setter 20.

However, when the fuel control lever 2 hits any of the stoppers 3 and 4 and the movement of the fuel control lever 2 is stopped, a difference occurs in the detection signals Pm and Ps. That is, in this case, the presence of the spring 6 changes the detection signal Pm of the motor rotation position detector 9 but does not change the detection signal Ps of the lever position detector 10, and the difference between these signals Pm and Ps is the fuel. Corresponds to the motor force currently applied to the control lever 2.

On the other hand, the lever driving force calculator 11 uses the detection signals Pm and Ps.
The amount of flexure of the spring 6 is calculated from the difference between the two, and the force Tr applied to the fuel control lever 2 by the motor 8 is calculated by multiplying this by the spring constant of the spring 6, and this calculated value Tr is abutted at this time. It is constantly compared with the optimum setting value Tr1 or Tr2 as the pressing force to the stopper 3 (or 4). Then, the difference between the detection signals Pm and Ps, that is, the motor force currently applied to the fuel control lever 2 is set value Tr1 (or T) for the stopper with which the lever 2 is in contact.
When r2) or more, the driving force limit signal TM is output from the comparator 15, and as a result, the motor 8 is stopped by the control of the deviation amplifier 14 as described above.

As described above, in this embodiment, when the fuel control lever comes into contact with the stoppers 3 and 4, the motor 8 is stopped when the pressing force against the stopper reaches a preset predetermined force. As shown in FIG. 3, even if the stopper position varies, the fuel control lever always comes into contact with the stoppers 3 and 4 with the set appropriate pressing force Tr1 or Tr2.

FIG. 4 shows a second embodiment of the present invention. In this case, a stepping motor is used as the motor 8. In the embodiment shown in FIG. 4, constituent elements common to those of the embodiment shown in FIG. 1 are designated by the same reference numerals, and overlapping description will be omitted.

That is, in this case, since the stepping motor 8 is used, the potentiometer for detecting the motor rotation position is not required, and the motor rotation position is determined by the stepping motor 8.
It is detected by counting the pulse signals that drive the.

In FIG. 4, the lever position command Sr set by the lever operation position setter 20 is converted into numerical data by the position command input unit 30.
The data is A / D converted and stored in the buffer 31. On the other hand, the current position of the rotary shaft of the motor 8 is detected by the current position counter 32, and the detected value is input to the pulse generator 33. Frequency data that determines the rotation speed of the motor 8 is set in the speed constant degree 34, and the set frequency data is input to the pulse generator 33.

The pulse generator 33 takes a deviation between the lever position command Sr stored in the buffer 31 and the detected value of the current position counter 32, and generates a drive pulse for matching the rotation axis of the motor 8 with the commanded position from this deviation. This drive pulse is output with a frequency equal to the frequency data set in the speed constant unit 34. Further, the pulse generator 33 determines the current motor rotation direction, and inputting this determination signal to the switch 18 switches and controls the switch 18.

The drive pulse output from the pulse generator 33 is supplied to the motor 8 via the signal output unit 19 and also input to the current position counter 32. The current position counter 32 calculates the current position of the motor 8 by updating the current count value according to the input drive pulse.

On the other hand, the current position Ps of the fuel control lever detected by the lever position detector 10 including a potentiometer is input to the lever detection position input unit 35, where A /
D converted and converted into numerical data.

The driving force calculation unit 36 takes the difference between the current position of the rotary shaft of the motor 8 counted by the current position counter 32 and the lever position data Ps input from the lever detection position input unit 35,
By multiplying this by the spring constant of the spring 6, the force Tr applied to the lever 2 is calculated, and this is input to the comparator 37.

The lever driving force setting devices 16 and 17 are set with pressing forces Tr1 and Tr2 against the fuel full position stopper 3 and the fuel cut position stopper 4 as in the previous embodiment, and these setting forces are selected by the switching device 18. It is input to the post-comparator 37.

The comparator 37 compares the driving force signal Tr input from the driving force calculator 36 with one of the torque setting values Tr1 or Tr2 selected by the switching device 18, and calculates the torque setting value Tr1 or Tr2.
When the driving force limit signal TM is equal to or higher than the driving force signal Tr, the driving force limit signal TM is input to the pulse generator 33.

The pulse generator 33 outputs the driving force limit signal from the comparator 37.
When TM is input, the drive pulse transmission is stopped, whereby the stepping motor 8 is stopped driving.

As described above, also in this embodiment, when the fuel control lever contacts the stoppers 3 and 4, the motor 8 is immediately stopped when the pressing force against the stopper reaches a predetermined force set in advance. .

In the above embodiment, the lever 7 is attached to the rotary shaft of the motor 8.
The rotation force of the motor 8 is converted into a sliding motion by the lever 7 and transmitted to the fuel control lever 2. However, a ring spring is used as the spring 6, and the rotation force (torque) of the rotation shaft of the motor 8 is changed. May be transmitted to the fuel control lever only by the rotation mechanism. In this case, when the fuel control lever is brought into contact with the stopper and the drive torque of the motor exceeds the set value, the motor is stopped.

〔The invention's effect〕

As described above, according to the present invention, when the fuel control lever contacts the stopper, the motor is immediately stopped when the driving force of the motor exceeds the optimum value set for the stopper. Even if there is manufacturing variation in the stopper position, the fuel control lever always comes into contact with the stopper with the optimum force, which prevents overheating of the motor and prevents the motor and fuel control. The bending margin of the spring arranged between the lever and the lever can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing a specific configuration for stop control of a motor, and FIG. 3 is a diagram showing a relationship between a motor stop position and a pressing force to a stopper according to the embodiment. 4 and 5 are views showing another embodiment, and FIG. 5 is a view showing a conventional device. 1 …… Governor, 2 …… Fuel control lever 3,4 …… Stopper, 5 …… Link, 6 …… Spring 8 …… Motor, 11 …… Lever driving force calculator 15 …… Comparator, 20 …… Lever Operation position setting device

Claims (3)

[Claims] 1. A governor drive control device for controlling an engine speed by connecting a fuel control lever having a stopper to a governor drive motor via a spring, and rotationally driving the governor drive motor. Position detecting means for detecting the rotational position of the fuel control lever, lever position detecting means for detecting the tilted position of the fuel control lever, lever position commanding means for commanding the tilted position of the fuel control lever, and the motor position detecting means And driving force calculation means for calculating the driving force applied to the fuel control lever based on the detection output of the lever position detection means, pressing force setting means for presetting an optimal pressing force for the stopper, and the driving force calculation The calculated driving force of the means is compared with the setting force of the pressing force setting means to calculate Comparing means for outputting a driving force limit signal when the driving force exceeds a set force; first subtracting means for taking a deviation between the command signal of the lever position commanding means and the detection value of the lever position detecting means; A deviation amplifier that amplifies the output of the subtraction unit 1 and outputs a stop signal that stops the motor when the driving force limit signal is input, and a deviation between the output of the deviation amplifier and the detection value of the motor position detection unit. And a motor control means for controlling the position of the governor drive motor in accordance with this deviation. 2. A governor drive controller for controlling an engine speed by connecting a fuel control lever having a stopper to a stepping motor via a spring and rotationally driving the stepping motor. Motor position detection means for detecting the fuel control lever, lever position detection means for detecting the tilt position of the fuel control lever, lever position command means for commanding the tilt position of the fuel control lever, the motor position detection means and the lever position Driving force calculation means for calculating the driving force applied to the fuel control lever based on the detection output of the detection means, pressing force setting means for presetting the optimum pressing force for the stopper, and calculation by the driving force calculation means Compare the driving force with the setting force of the pressing force setting means When the calculated driving force is equal to or greater than the set force, the stepping motor is driven so that the deviation between the comparing unit that outputs the driving force limit signal and the command value of the lever position commanding unit and the detection value of the lever position detecting unit becomes zero. A governor drive control device comprising: a motor control unit that controls and stops the stepping motor when the drive force limit signal is input. 3. A stopper is provided for each of the speed increasing side and the speed reducing side, and two different pressing force set values are set in the pressing force setting means in correspondence with these two stoppers. The governor drive control device according to (1) or (2).