JPH06171894A - Automatic constant speed control device for winch - Google Patents

Abstract

PURPOSE:To quickly settle a speed to the set speed regardless of disturbance during operation of a winch by multiplying a deviation between the set speed and the actual speed by a feedback gain in response to the set speed, and adding the integrated value of the product to an initial control value so as to generate a speed control value. CONSTITUTION:In a winch of which a winch drum driven by a hydraulic motor receiving discharge oil of an oil pressure pump 1 is wound with a rope suspendingly supporting an auger unit, when automatic constant speed operation is selected, a reference control value Po in response to the scheduled execution speed Vo set by means of a speed setter 31 is output from a function generator 32. The deviation DELTAV between the speed signal V of winding rope output from a speed detector 25 and the execution speed Vo is obtained, the devation DELTAV is multiplied 34 by a feedback gain G output according to the execution speed Vo, and the multiplied value is integrated 35 so as to obtain a control value P. Next, the control value P is added 36 to the reference control value Po so as to obtain a command signal P so as to utilize it for controlling the discharge quantity of the oil pressure pump 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a winch automatic constant speed controller.

[0002]

2. Description of the Related Art When an auger unit is attached to a pile driver or a crane to carry out ground improvement work, it is necessary to match the chemical solution injection speed with the hoisting / lowering speed of the auger unit in a low speed range. is there. In such work, conventionally, an ultra-low speed operation was performed by a hydraulic ultra-low speed control device provided in the machine body.

However, since this conventional ultra-low speed control device does not feed back the loop speed at all,
The changing of the drum winding layer of the hydraulic hoist winch changes the rope speed. For this reason, the operator operates the engine accelerator lever while looking at the speed meter of the separately installed rope to sequentially control the engine rotation speed to increase or decrease the rotation speed of the hydraulic pump, and By controlling the rotation speed of the hoisting winch, constant speed control of the rope is performed. Therefore, the operation is complicated and it is difficult to maintain a constant speed.

Therefore, the constant speed control device shown in FIG. 4 has been conventionally used. This control device detects the construction speed Vo. The automatic constant speed control device 50 adds the deviation Vo-V (= ΔV) between the construction speed Vo set by the setting device 51 and the hoisting loop speed V detected by the speed detector 61 to the addition point 5
The difference ΔV is multiplied by a coefficient K in a coefficient unit 53 to obtain K · ΔV. This K · ΔV is input to the integrator 54 and added to the previous control value P to obtain a new control value P. This control value P is input to the electromagnetic proportional pressure reducing valve 16.
The electromagnetic proportional pressure reducing valve 16 regulates the hydraulic pump 1.
The pressure guided to the controller 1a is adjusted, and the pressure corresponding to the input control value P is applied to the regulator 1a. As a result, the discharge volume of the hydraulic pump 1 is controlled, the discharge flow rate of the hydraulic pump 1 is adjusted, and the rotational speed of the hydraulic winch is maintained at a predetermined value.

[0005]

The automatic constant speed control according to this method is performed when a speed fluctuation occurs at the start of control or when a disturbance occurs due to irregular winding of the hoisting loop or fluctuations in the engine speed, etc. Since (the above-mentioned ΔV) is large, the response until it converges to the set construction speed Vo is very slow, and speed hunting is likely to occur.

This automatic constant speed control device is sometimes used as an ultra-low speed automatic constant speed control device for auger work on hard ground, etc. And the speed of excavation do not match, the hanging rope of the auger may become loose and the auger may float.
At this time, when the suspension rope becomes loose, the detected speed shows a value smaller than the actual value or zero, and the speed deviation by the automatic constant speed control device becomes positive, and the command value for acceleration is output. For this reason, the feeding speed of the auger unit is further increased, and not only the ultra-low speed constant speed control is not achieved, but also the winch drum is wound irregularly.

Furthermore, since the automatic constant speed control device described above does not automatically control the engine speed, if the engine speed is set incorrectly, the required discharge amount in the control range cannot be obtained from the hydraulic pump. There is also a possibility that control will not be possible at all.

An object of the present invention is to provide an automatic constant speed control device for winches, which solves these various problems.

[0009]

SUMMARY OF THE INVENTION The present invention is a device for suspending a work attachment on a winch mounted on a main body of a work machine and automatically controlling a hoisting / lowering speed of the work attachment. , A speed setter for setting a hoisting / lowering speed of the work attachment, a speed detector for detecting a hoisting / lowering speed of the work attachment, and a deviation between the set speed and an actual speed In a winch automatic constant speed control device comprising a deviation device and outputting a speed control value for controlling the hoisting / lowering speed based on the deviation, an initial control value according to the set speed. An initial control value generating means, a feedback gain generating means for generating a feedback gain according to the set speed, the deviation and the feedback gain By providing a multiplier that takes the product of, the integrator that takes the integrated value of the product, and an adder that adds the initial control value and the integrated value to generate the speed control value, To achieve.

[0010]

The initial control value generating means generates the initial control value according to the set speed. This initial control value is added in the adder with the output of the integrator to form the speed control value. Although the integral value is zero at the start of control, the winch is driven at the planned construction speed quickly because the speed control value is formed according to the initial control value. Further, during the work, the deviation between the set speed and the actual speed is taken, and the product is integrated by multiplying the feedback gain corresponding to the set speed and this deviation, and further the initial control value and the integrated value. Since the speed control value is generated by adding, the actual speed quickly converges to the set speed by the feedback gain that takes a value corresponding to the set speed even if the actual speed greatly changes due to disturbance.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. First, the hoisting winch hydraulic circuit will be described with reference to FIG. In FIG. 2, reference numeral 1 denotes a variable displacement hydraulic pump (hereinafter simply referred to as a hydraulic pump) driven by an engine (not shown). On the discharge side of the hydraulic pump 1, a directional switching valve 2 for controlling the discharge oil and a circuit pressure are provided. And a relief valve 3 for setting The direction switching valve 2 is connected to the pipelines 5 and 6 communicating with the hoisting hydraulic motor 4, and a counterbalance valve 7 is installed in the pipelines 5 and 6.
At the pilot ports 2a and 2b of the direction switching valve 2, the pilot valve 1 for adjusting the discharge pressure of the pilot hydraulic pump 8 is provided.
The secondary pressure corresponding to the manipulated variable of 1 is supplied through the pipe lines 9 and 10, and the direction of the direction switching valve 2 is switched and controlled by the supplied pressure to control the direction and flow rate of the pressure oil to the hydraulic motor 4. It Further, the output pressure of the pilot valve 11 is guided to the pipe line 13 via the shuttle valve 12, and can be supplied to the regulator 1a of the hydraulic pump 1 via the electromagnetic switching valve 14 provided in the pipe line 13. There is.

Discharge oil from the pilot hydraulic pump 8 can be supplied to the regulator 1a via an electromagnetic proportional pressure reducing valve 15, a pipe line 16 and an electromagnetic switching valve 14. This electromagnetic proportional pressure reducing valve 15 is provided with an automatic constant speed control device 30.
Driven by a command signal from the control unit, the output pressure is adjusted. That is, the electromagnetic switching valve 14 is switched to the a position when the switch 17 is turned on and is switched to the b position when the switch 17 is turned off. At the position a, the output pressure of the electromagnetic proportional pressure reducing valve 15 is supplied to the regulator 1a, and at the position b, the output pressure of the pilot valve 11 is supplied to the regulator 1a. The switch 17 is installed between the battery 18 and the solenoid portion of the electromagnetic switching valve 14. Furthermore, in order to detect the operation direction of the pilot valve 11, pressure switches 19a and 19b are provided in the pilot pipe lines 9 and 10.

In FIG. 2, a winch drum 21 is connected to the hydraulic motor 4, and a rope 22 wound around the winch drum 21 supports an auger unit 24 via a sheave 23. The sheave 23 is provided with a speed detector 25 such as a rotary encoder to detect the speed of the rope 22.

Further, in FIG. 2, the automatic constant speed control device 30 includes a speed setting device 31, which receives signals from the speed detector 25 and signals from the pressure switches 19a and 19b and sets them by the speed setting device 31. Winding up to speed Vo
In order to control the speed V, a command signal is sent to the electromagnetic proportional pressure reducing valve 15 as described later.

Next, the automatic constant speed controller 30 will be described with reference to FIG. The automatic constant speed controller 30 includes a speed setter 31.
, A function generator 32, an addition point 33, a multiplier 34,
It has an integrator 35, an addition point 36, and a gate circuit 37. The speed setter 31 sets the construction speed Vo. The function generator 32 indicates the construction speed Vo set and input by the speed setter 31 and the standard control value Po which is the input current to the electromagnetic proportional pressure reducing valve 15 as shown by the solid line I in FIG. Generate a function associated with. Also, the construction speed Vo and Fig. 3
A function is generated by associating the inclination of the function indicated by the solid line I in FIG. 3A with the slope indicated by the solid line J in FIG. That is,
The standard control value Po and the feedback gain G are respectively output with respect to the input construction speed Vo.

The addition point 33 is a deviation Vo-V between the hoisting loop speed V output from the speed detector 31 and the construction speed Vo.
= ΔV is obtained. The multiplier 34 has a feedback gain G
And the deviation ΔV are multiplied. The integrator 35 integrates the multiplication result G · ΔV and outputs the control value P. Addition point 36
Is the standard control value Po from the function generator 32 and the integrator 35.
And the control value P from are added to obtain a new control value P. The gate circuit 37 is closed when the pressure switch 19 is turned on,
The control value P output from the adder 36 is supplied to the electromagnetic proportional pressure reducing valve 15 as a command signal.

Next, the operation will be described. Switch 1
7 is turned on to switch the electromagnetic switching valve 14 to the a position and the automatic constant speed operation is selected. Next, the construction speed Vo of the auger unit 24 is planned and set by the speed setter 31 provided in the automatic constant speed controller 30. The operating lever 11a of the hoisting winch is fully operated to either the upper side or the lower side to lock the operating lever 11a in a detent manner. At this time, since the pressure oil is not supplied to the regulator 1a of the hydraulic pump 1, the pump discharge amount is zero. Lever-11
By operating a, the pilot valve 11 is operated, the pressure switch 19 is closed, and a signal for starting control is input to the automatic constant speed control device 30. When the control start signal is input, the gate circuit 37 is closed. When the control is started by the gate closing operation,
A standard control value Po corresponding to the planned construction speed Vo is output from the function generator 32 and added to the addition point 36. Since one input of the addition point 36 is zero at the start of control, this standard control value (indicating the input current value) Po is sent to the electromagnetic proportional pressure reducing valve 15 via the gate circuit 37. This command signal is converted into a secondary pressure by the electromagnetic proportional pressure reducing valve 15, and this pressure is input to the regulator 1a of the hydraulic pump 1.

As a result, the displacement volume of the hydraulic pump 1 increases from zero and pressure oil starts to be discharged, is guided to the hydraulic motor 4 through the direction switching valve 2, and the winch drum 21 starts rotating. Then, when the speed detector 25 outputs a signal corresponding to the speed of the hoisting loop 22, that is, the hoisting rope speed V, the addition point 33 calculates Vo-V (= ΔV), and this deviation ΔV is multiplied by the feedback gain G output from the function generator 32 according to the construction speed Vo, and the integrator 3
Input to 5. The integrator 35 integrates G · ΔV and outputs a control value P. At the addition point 36, the standard control value Po from the function generator 32 and the control value P from the integrator 35 are added, and the command signal (input current value) P as the addition result is passed through the gate circuit 37. And supplies it to the electromagnetic proportional pressure reducing valve 15.
As a result, the secondary pressure corresponding to the command signal is output from the electromagnetic proportional pressure reducing valve 15 and supplied to the regulator 1a via the conduit 16 and the electromagnetic switching valve 14. As a result, the deviation △
Since the displacement volume of the hydraulic pump 1, that is, the discharge flow rate is increased or decreased according to V, the rotation speed of the winch drum 21 is controlled, and the hoisting speed V approaches the construction speed Vo.

As described above, when the control is started, the output of the integrator 35 is zero, but the standard control value Po is output from the function generator 32. Therefore, the addition point 36 changes the control value Po to the electromagnetic proportional pressure reducing valve. Send to 15. Therefore, the rising responsiveness is improved. After startup, the control value P is

[Formula 1] P = Po + ∫G · ΔVdt is corrected.

The feedback gain G mentioned above will now be described. Now, as shown in FIG. 3A, the planned construction speed Vo is V _A and the hoisting and winding speed V is V _B (> V _A ). The control value P for the planned construction speed Vo = V _A is P _A ,
The control value P for the hoisting loop speed V = V _B is P _B.
That is, the control value P may be lowered to P _B → P _A in order to reduce the hoisting and rope speed V to V _B → V _A. The speed deviation ΔV _AB between the speeds V _A and V _B and the control value deviation ΔP _AB between the control values P _A and P _B are

[Formula 2] V _B −V _A = ΔV _AB > 0

## EQU3 ## When represented by P _B -P _A = ΔP _AB > 0, the control value P _A is

(4) P _A = P _B −ΔP _AB = P _B − (ΔV _AB · G) (1) Therefore, this equation (1) is shown in FIG.
In order to determine the feedback gain G so as to be satisfied in the entire region of (a), the feedback gain G is set as shown in FIG.
3B, the feedback gain G can be represented by a function J of the construction speed Vo as shown in FIG. That is, the function J in FIG. 3B represents the slope of the function I shown in FIG. Further, the function I is determined corresponding to the PQ line of the hydraulic pump 1.

Incidentally, for example, when the actual speed is zero for a predetermined time or more, or when the two pressure switches 19a and 19b are both turned on, it is judged as abnormal and the gate circuit 3 is determined.
You may open 7. This causes the winch to stop.
When the abnormal state is resolved, the winch starts driving again, but in this case as well, the initial control value Po is output, so it is possible to drive at the set speed immediately.

[0022]

As described above, according to the present invention,
Since the initial control value and feedback gain corresponding to the set speed are output, the time to converge to the predetermined set speed at the start of work or speed fluctuation due to disturbance is shortened and the responsiveness is improved. . Hunting is also prevented.

[Brief description of drawings]

FIG. 1 is an overall block diagram of an automatic constant speed control device according to an embodiment of the present invention.

FIG. 2 is an overall configuration diagram including a hydraulic circuit of an automatic constant speed control device according to an embodiment.

FIG. 3 is a diagram illustrating a function of the function generator of FIG.

FIG. 4 is a block diagram showing a conventional automatic constant speed control device.

[Explanation of symbols]

 1 hydraulic pump 1a regulator 2 directional switching valve 4 hydraulic motor 8 hydraulic pump for pilot 11 pilot valve 14 electromagnetic switching valve 15 electromagnetic proportional pressure reducing valve 17 selection switch 19a, 19b pressure switch 21 winch drum 22 rope 23 speed detector 24 auger unit 30 Automatic constant speed controller 31 Speed setter 32 Function generator 33 Addition point 34 Multiplier 35 Integrator 36 Addition point 37 Gate circuit

Claims (1)

[Claims] 1. A device for suspending a work attachment on a winch mounted on a main body of a work machine and automatically controlling a hoisting / lowering speed of the work attachment by a constant speed. A speed setting device for setting the hoisting speed and hoisting of the work attachment
A speed detector for detecting the hoisting speed and a deviation device for taking a deviation between the set speed and the actual speed are provided, and a speed control value for controlling the hoisting / lowering speed is output based on the deviation. In the winch automatic constant speed control device, an initial control value generating means for generating an initial control value according to the set speed, and a feedback gain generation for generating a feedback gain according to the set speed Means, a multiplier for taking a product of the deviation and the feedback gain, an integrator for taking an integrated value of the product, and an adder for adding the initial control value and the integrated value to generate the speed control value. An automatic constant speed control device for winches, comprising: