JPH07138990A - Operating device for working machine - Google Patents

Abstract

PURPOSE:To operate various driving sections arbitrarily without requiring space. CONSTITUTION:When an 'accelerator' is selected by a selecting section 7, a changeover section 81 is changed over to a position shown in the figure. A signal from a signal generator 3a is input to an engine-control motor control section 83 according to the position of the operation of an engine lever 3, and an engine control motor 2 is driven to adjust a governor 1. When a pedal 6 is depressed, a signal corresponding to the quantity of depression is output from a signal generator 6a and compared with the signal of the signal generator 3a by a maximum-value selection section 82, so that the engine control motor 2 is driven by the larger signal. The changeover section 81 is changed over to the proportional solenoid-valve control section 84 side when a 'breaker' is selected by the selecting section 7, a proportional solenoid-valve control section 84 drives a proportional solenoid valve 5 by the signal of the signal generator 6a when the pedal 6 is depressed, and the breaker is driven through a control valve 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operating device for a working machine for operating various driving parts of the working machine such as a hydraulic excavator.

[0002]

2. Description of the Related Art There are various types of working machines such as hydraulic excavators, hydraulic cranes, etc., each of which is equipped with various driving parts, and by driving the driving parts, desired work can be performed. . For example, a hydraulic excavator includes an engine, a hydraulic pump driven by the engine, a boom cylinder driven by the discharge oil of the hydraulic pump, an arm cylinder, a bucket cylinder, a swing motor, a traveling motor, and a displacement volume of the hydraulic pump. Various drive units such as a regulator for driving the variable mechanism are provided, and a desired work such as excavation is performed by selectively driving these drive units. Further, attachments such as a breaker, a crusher, and a vibrating pile driving device are attached to the hydraulic excavator as other driving parts, and work is often performed using these attachments. Each drive unit of such a working machine is driven by the corresponding operation lever.

[0003]

The work machine has a drive which is not used for normal work but only for special purposes. In the example of the hydraulic excavator, each attachment described above corresponds to this. As described above, the hydraulic excavator must be provided with an operation means for operating the drive part even if it is used infrequently, and a space in the cab for the operation means is required.

Further, even with a drive unit that is normally used, there is frequently a desire to drive the drive unit in a relationship other than the preset relationship between the operation amount and the drive amount. For example, when performing work by energy saving or fine operation, the engine rotation speed is set to a low rotation speed by the engine lever and the work is performed based on the engine rotation speed. There are times when you want to increase or decrease the number and perform appropriate work. Furthermore, there are cases where it is desired to drive the drive unit at a speed and force suitable for the work by continuously adjusting a preset set value. In these cases as well, in order to meet the demand, it is necessary to separately provide an operating means, and a space for that is required.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems in the prior art and to provide an operating device for a working machine capable of arbitrarily operating various drive parts without requiring space.

[0006]

In order to achieve the above object, the present invention provides a working machine which drives a plurality of drive units to perform a required work, and is operated continuously by a person to continuously perform the operation. An operating means for outputting an operation signal, and a selecting means for selecting a drive section which gives an operation signal from the operation means among the respective drive sections and making a required connection.

[0007]

When the operating means is operated, an operation signal corresponding to the operation amount is output. This operation signal is given to the drive unit selected by the selection means, and drives the drive unit according to the operation amount. If you select another drive unit by the selection means,
The other drive unit is driven by the operation means according to the operation amount.

[0008]

The present invention will be described below with reference to the illustrated embodiments. 1 is a block diagram of an operating device for a hydraulic excavator according to a first embodiment of the present invention. In this figure, 1 is a governor for adjusting the fuel injection amount of an engine (not shown), 2
Is an engine control motor that drives the governor 1, 3
Is the engine lever that sets the target engine speed, 3
Reference numeral a is a signal generator that outputs an electric signal according to the operation of the engine lever, reference numeral 4 is a control valve that controls the drive of a breaker (not shown), and reference numeral 5 is a proportional solenoid valve that drives the control valve 4.

6 is a pedal, 6a is a signal generator for generating an electric signal according to the operation amount of the pedal 6, 7 is "off",
A selector 8 having three setting positions of "accelerator" and "breaker" is a control device. The control device 8 includes a selection unit 7
The switching unit 81 that is switched according to the setting of the maximum value selecting unit 82 that selects the larger one of the signal from the signal generator 3a and the signal from the switching unit 81, and the maximum value selecting unit 8
The engine control motor control unit 83 controls the engine control motor according to the signal No. 2 and the proportional solenoid valve control unit 84 controls the proportional solenoid valve 5. The selection unit 7 and the switching unit 81 constitute a selection device.

FIG. 2 is a plan view of the inside of the cab of a hydraulic excavator equipped with the device shown in FIG. In this figure, 10 indicates a driver's cab. 101L and 101R are operating levers for hydraulic actuators such as boom cylinders, arm cylinders, bucket cylinders, and swing motors; 102 is a switch panel;
Reference numeral 03 is a key switch, 104 is a rear tray, 105 is a pilot control shut-off lever that locks a pilot circuit, 106L and 106R are operation levers with dampers, and 107 is a seat. The pedal 6 shown in FIG. 1 is installed in the front part of the operator's cab 10 and operated by the feet of the operator of the hydraulic excavator.

Next, the operation of this embodiment will be described. When performing the work by finely operating the hydraulic actuator, the engine lever 3 is set to the low rotation speed position, and the selection unit 7 selects "accelerator". By this selection, the switching unit 81 is switched to the maximum value selection unit 81 side. The signal generator is
It outputs an electrical signal according to the set rotation speed.
When the pedal 6 is not operated, a signal corresponding to the low target rotation speed set by the engine lever 3 is input to the engine control motor control unit 83, and the engine control motor 2 is driven according to this signal to adjust the governor 1. Then, the engine rotates at a low rotation speed, and a low flow rate of pressure oil is discharged from a hydraulic pump (not shown). As a result, the hydraulic actuator is driven at a low speed to enable the operator to perform fine operation.

In this state, if the operator wants to drive the hydraulic actuator at a higher speed, the pedal 6
When the user depresses, the signal generator 6a outputs a signal corresponding to the amount of depression, and this signal is the maximum value selection unit 82.
Is compared with the signal from the signal generator 3a, and if the former signal exceeds the latter signal, the engine control motor control unit 83 causes the former signal (the signal from the pedal 6).
The engine control motor 2 is driven based on
As a result, the engine speed increases in accordance with the amount of depression of the pedal 6, the discharge flow rate of the hydraulic pump can be increased and the hydraulic actuator can be driven at a high speed even during fine operation work.

When a breaker is attached to the hydraulic excavator as an attachment and the "breaker" is selected in the selection unit 7, the switching unit 81 causes the proportional solenoid valve control unit 84 to operate.
Is switched to the side. In this state, when the operator depresses the pedal 6 to operate the breaker, the signal generator 6
A signal corresponding to the depression amount of the pedal 6 is generated from a, and the proportional solenoid valve control unit 84 drives the proportional solenoid valve 5 in response to the signal. As a result, the control valve 4 is driven, and the breaker is driven according to the driving amount. That is,
The breaker is driven according to the depression amount of the pedal 6.

With the above-described structure, in the present embodiment, it is not necessary to provide operating means for controlling the engine speed and driving the breaker, respectively, and controlling the engine speed and driving the breaker selectively with one pedal. Can be done

FIG. 3 is a block diagram of an operating device for a hydraulic excavator according to a second embodiment of the present invention. In this figure,
The same parts as those shown in are indicated by the same reference numerals. Reference numeral 9 is a selection device, and 80 is a control device corresponding to the control device 8 shown in FIG. The selection device 9 is a device in which the selection unit 7 and the switching unit 81 shown in FIG. 1 are integrally configured, and the switching unit may be configured to be switched by a signal or mechanically. Good. The control device 80 is configured without the switching unit 81 in the control device 8 shown in FIG. The operation and effect of this embodiment are similar to the operation and effect of the device shown in FIG.

FIG. 4 is a block diagram of a hydraulic shovel operating device according to a third embodiment of the present invention. In this figure, 6 is a pedal, 6a is its signal generator, and 9 is a selector, which are the same as those shown in FIG. 11 is a boom lever, 12 is an arm lever, 13 is a bucket lever, and 14 is a turning lever, and their signal generators are indicated by reference numerals 11a to 14a. Reference numeral 15 is a control device, and in addition to the selection device 9, characteristic signal output units 151 to 15
4, a gain output unit 155 and a multiplication unit 157. _{S 1, S 2, S 3} , S respectively boom control valve _4, the arm control valve, the bucket control valve, control valves for the swing motor (these shown are omitted) showing the output signal to.

Each of the characteristic signal output sections 151 to 154 and the gain output section 155 is composed of a memory or a function generator of a microcomputer, and these characteristic signal output sections 151 to 154 are shown according to the operation amount of each lever. The gain output unit 155 outputs a signal according to the illustrated characteristic according to the depression amount of the pedal 6. The gain output unit 155 indicates that the signal from the selection device 9 is “0” (when the pedal 6 is not selected by the selection device 9 or when the depression amount of the pedal 6 is 0 even if it is selected). ) Output the numerical value "1".

Next, the operation of this embodiment will be described. When the gain output unit 155 is not selected by the selection device 9 (in the case of normal operation of each control valve), the signal output from the gain output unit 155 to each multiplication unit 157 is “1”, and thus each signal S _{1 to} S ₄ are signals according to the characteristics of the special signal output sections 151 to 154 with respect to the operation amounts of the levers 11 to 14, and the control valves are operated according to the signals to drive the corresponding hydraulic actuators. To be done.

On the other hand, when the gain output section 155 is selected by the selection device 9 and the operator of the hydraulic excavator depresses the pedal 6, a signal is output from the signal generation device 6a according to the amount of depression, and this signal is It is input to the gain output unit 155 via the selection device 9, and is input to the gain output unit 155.
Outputs a numerical value (gain) corresponding to the input signal. This numerical value is used by each multiplication unit 157 for each characteristic signal output unit 1.
The signals from 51 to 154 are multiplied, whereby the signals S _{1 to} S ₄ become signals that are higher than the output signals of the characteristic signal output units 151 to 154.

With the above-mentioned configuration, in this embodiment, one pedal is used to operate each hydraulic actuator in addition to the operation such as the engine speed adjustment and the breaker driving as in the previous embodiment. It can be driven at a speed faster than the normal speed with respect to the operation amount of the lever. That is, when the operator of the hydraulic actuator wants to increase the effect of the operation lever (the magnitude of the displacement of the control valve with respect to the stroke of the operation lever) in order to respond to the work situation,
This can be achieved by stepping on the pedal 6. Then, the degree of effectiveness of the operation lever can be adjusted by the depression amount of the pedal 6.

In the description of this embodiment, an example in which the same gain is simultaneously given to the operation signals of the respective levers has been described, but the present invention is not limited to this, and the gain may be given only to a specific lever. However, it is also possible to give a specific different gain to each lever.

FIG. 5 is a block diagram of an operating device for a hydraulic excavator according to a fourth embodiment of the present invention. In this figure, 6 is a pedal, 6a is its signal generator, and 9 is a selector, which are the same as those shown in FIG. In the present embodiment, the tilt amount of the variable displacement mechanism of the hydraulic pump (variable displacement type) (not shown) mounted on the hydraulic excavator can be adjusted by the pedal 6. The agate volume changing mechanism is driven by a hydraulic cylinder (not shown), and the hydraulic cylinder is provided with a solenoid valve 24 (not shown).
By selectively driving A and 24B, they are displaced to one or the other to increase or decrease the tilt amount of the displacement capacity varying mechanism. 250A shown in the figure is a control device for controlling the solenoid valves 24A, 24B.
A, 24B, and the hydraulic cylinder constitute a regulator for the variable volume of the astringent volume. The control device 250A is described in detail in Japanese Patent Application Laid-Open No. 4-258418, so only the following outline description will be given in this embodiment.

In FIG. 5, reference numeral 18 is a tilt angle sensor for detecting the actual tilt amount of the above-mentioned displacement control mechanism, and 19 is a difference for detecting the difference between the discharge pressure of the hydraulic pump and the maximum load pressure of the hydraulic excavator. A pressure sensor, 20 is a rotation speed sensor for detecting the rotation speed of the engine, 21 is a potentiometer for detecting the operation position of the governor lever of the engine, 22 is a pressure sensor for detecting the pilot pressure proportional to the operation amount of the traveling motor of the hydraulic excavator, Reference numeral 23 is a pressure sensor for detecting the discharge pressure of the hydraulic pump. The control device 250A includes a target differential pressure setting unit 251a, an addition unit 251b, a load sensing control unit 251, which includes a calculation unit 251c, a torque control unit 252, a minimum value selection unit 253, and a servo control unit 254.

In the load sensing control section 251, the differential pressure set in the target differential pressure setting section 251a and the differential pressure sensor 19 are set.
The actual differential pressure detected in 1 is compared by the adding unit 251b, and the tilt amount for eliminating this difference is calculated by the calculating unit 251c based on the difference between the two. On the other hand, the torque control unit 25
2 is obtained by inputting the detection values of the rotation sensor 20, the potentiometer 21, and the pressure sensor 22 to calculate a target torque for preventing engine stall, and multiplying this target torque by the reciprocal of the detection value of the pressure sensor 23. Is calculated. The minimum value selection unit 253 selects the smaller tilt amount of the output of the load sensing control unit 251 and the output of the torque control unit 252, and the servo control unit 254
One of the solenoid valves 24A and 24B is compared so that the tilt amount selected by the minimum value selection unit 253 and the actual tilt amount detected by the tilt angle sensor 18 are compared so that the difference between the two falls within an allowable range. To drive. As a result, the hydraulic pump can be driven with an appropriate tilt amount with respect to the load of the hydraulic shovel.

By the way, the operator of the hydraulic excavator may want to set the driving speed of the hydraulic actuator to a speed other than the normal speed depending on the work contents and the surrounding conditions. In this embodiment, the pedal 6 used in each of the previous embodiments can meet the above-mentioned demands without providing a separate operating means. That is, in this embodiment, the target differential pressure set in the target differential pressure setting unit 251a is arbitrarily changed according to the depression amount of the pedal 6. As a result, the tilting amount output from the load sensing control unit 251 can be changed to change the discharge flow rate of the hydraulic pump, and thus the driving speed of the hydraulic actuator, to a speed according to the operator's feeling.

FIG. 6 is a block diagram of an operating device for a hydraulic excavator according to a fifth embodiment of the present invention. In this figure,
The same parts as those shown in are indicated by the same reference numerals. 25
Reference numeral 0B is a control device corresponding to the control device 250A of the fourth embodiment, and reference numeral 255 is a minimum value selection unit interposed between the minimum value selection unit 253 and the servo control unit 254 in the control device 250B.

In the present embodiment, a signal corresponding to the depression amount of the pedal 6 is input to the minimum value selection unit 255 as a tilt amount signal, where it is compared with the output signal from the minimum value selection unit 253. Therefore, the maximum tilt angle of the hydraulic pump can be limited by the pedal 6, and the pedal 6 can be used to adjust the stepping amount, for example, during fine operation of the hydraulic excavator without providing a separate operating means. Thus, a more delicate operation can be performed.

FIG. 7 is a block diagram of an operating device for a hydraulic excavator according to a sixth embodiment of the present invention. In this figure,
The same parts as those shown in are indicated by the same reference numerals. 25
0C is a control device corresponding to the control device 250A of the fourth embodiment, and 256 is a maximum value selection unit interposed between the minimum value selection unit 253 and the torque control unit 252 in the control device 250C.

In the present embodiment, a signal corresponding to the depression amount of the pedal 6 is input to the maximum value selection unit 256 as a tilt amount signal, where it is compared with the output signal from the torque control unit 252. Therefore, the tilt amount signal from the pedal 6 becomes a signal equivalent to the signal based on the torque of the hydraulic excavator. As a result, the pedal 6 can be operated without providing a separate operating means.
For example, when the force is being used to the maximum in excavation work or the like, and when a larger force is desired to be used for a short time, the pedal 6 is depressed to increase the tilting amount, thereby achieving the purpose. . When the work is not performed, the amount of tilt is increased by depressing the pedal 6 to increase the discharge flow rate in advance, and the required flow rate is immediately obtained when the operation lever is operated at the start of the next work. You can also

In the description of each of the above embodiments, the hydraulic excavator was illustrated as the working machine, but it is obvious that the present invention can be applied to other working machines. Further, it is obvious that the selection device and the control device can be constituted by a microcomputer. Furthermore, in the description of each of the above-described embodiments, the pedal is exemplified as the operation means, but this may be an operation lever or an operation portion integrally installed with a normal operation lever. .

[0031]

As described above, according to the present invention, the operating means for continuously outputting the operating signal in response to the operation is connected to the portion for driving the driving section by the selecting means, and the operating signal from the operating means is used. Since the drive unit is driven, various drive units can be arbitrarily operated without requiring space.

[Brief description of drawings]

FIG. 1 is a block diagram of an operating device for a hydraulic excavator according to a first embodiment of the present invention.

FIG. 2 is a plan view of a driver's cab in which the pedal shown in FIG. 1 is installed.

FIG. 3 is a block diagram of an operating device for a hydraulic excavator according to a second embodiment of the present invention.

FIG. 4 is a block diagram of an operating device for a hydraulic excavator according to a third embodiment of the present invention.

FIG. 5 is a block diagram of an operating device for a hydraulic excavator according to a fourth embodiment of the present invention.

FIG. 6 is a block diagram of an operating device for a hydraulic excavator according to a fifth embodiment of the present invention.

FIG. 7 is a block diagram of an operating device for a hydraulic excavator according to a sixth embodiment of the present invention.

[Explanation of symbols]

 1 Governor 2 Engine control motor 3 Engine lever 4 Control valve 5 Proportional solenoid valve 6 Pedal 7 Selection part 8 Control device 81 Switching part 82 Maximum value selection part

Claims (8)

[Claims] 1. A working machine for driving a plurality of drive units to perform a required work, and an operating means for continuously outputting an operation signal in response to the operation by a person operating the operation machine, and each of the drive units. An operating device for a working machine, characterized by further comprising: selecting means for selecting a drive section which gives an operation signal from the operating means and making a required connection. 2. The operating device for a working machine according to claim 1, wherein the operating means is a foot pedal. 3. The operating device for a working machine according to claim 1, wherein the operating means is provided on an operating lever of another drive unit. 4. The operating device for a working machine according to claim 1, wherein the drive unit selected by the selecting means is an engine control device. 5. The operating device for a working machine according to claim 1, wherein the drive unit selected by the selection unit is a regulator that drives a variable displacement mechanism of the hydraulic pump. 6. The operating device for a working machine according to claim 1, wherein the drive unit selected by the selecting unit is a control valve. 7. The operating device for a working machine according to claim 6, wherein the control valve is driven in response to an operation signal from the operating means. 8. The control valve according to claim 6, wherein the control valve is driven according to a value obtained by multiplying an operation amount of an operation lever of the control valve by a gain according to an operation signal from the operation means. Working machine operating device.