JPH0977468A - Operative speed controller of hydraulically operated equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable it to smoothly perform changeover from a slow speed mode to a power mode without entailing a large shock to hydraulically operated equipment by installing an operative speed controller which controls the opening of a control valve according to an operated variable, in time of this slow speed mode, and shifting it to the power mode in succession. SOLUTION: Control over a turning motor, a derricking cylinder, a winch motor and and extensible cylinder as an actuator in a hydraulic circuit of a truck-mounted type crane is made so as to be done by a control 30 which is made up of installing two joystick levers 31 and 32 arranged vertically, and a mode selector dial 343 being selectable to both slow speed and power modes. In the case where the slow speed mode is selected by a mode selector dial 33, a control valve is gradually opened in proportion to a tilt of the joystick lever 31, and a control shear is fully opened at the maximum tilt angle, and further engine speed to adjust an amount of pump discharge is made so as to maintain it to be somewhat a higher value than the idling.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operating speed control device for hydraulically operated equipment, for example, in a crane device,
It is used to control hydraulic equipment such as boom hoisting cylinders, boom telescopic cylinders, swing motors and winch motors.

[0002]

2. Description of the Related Art Conventionally, in a crane apparatus, for example, a boom raising / lowering operation, a telescopic operation, a turning operation, and a winch operation are performed by a boom raising / lowering cylinder, a boom telescopic cylinder,
The operation is performed by hydraulic operating devices such as a swing motor and a winch motor, and the operating amounts of the respective hydraulic operating devices are controlled so as to operate in accordance with an operation amount of an operation lever provided in an operation device. I have.

[0003]

However, in the above-described conventional apparatus in which the operation of each hydraulic operating device is simply controlled in accordance with the tilt angle of the operation lever, the operation of the operation lever cannot be controlled from the viewpoint of workability. Each hydraulic operating device is set to operate quickly, which makes it difficult to operate the hydraulic operating device at a very low speed by minute operation of the operation lever.For example, when you want to move a heavy suspended load slowly Also, it is not suitable when the position of the suspended load is to be moved slightly, and there is a risk that an accident may occur due to erroneous operation.

Therefore, in the prior art, Japanese Patent Laid-Open No. 4-34
As seen in the one described in Japanese Patent No. 7001 publication, there is provided one that performs a fine speed operation by switching between a fine speed mode and a power mode.

However, if the mode is switched from the slow speed mode to the power mode in the middle of operation, the supply of pressure oil increases sharply, which gives a large shock to the hydraulically operated equipment. Met. Therefore, the switching from the slow speed mode to the power mode is usually performed after the operation is once stopped, and there is a problem that the operability is poor.

[0006]

SUMMARY OF THE INVENTION An operating speed control device for hydraulically operated equipment according to the present invention is a control valve for controlling hydraulically operated equipment operated by supply of pressure oil from a pressure oil supply source operated by drive means. And a mode configured to freely switch the operation of the hydraulically operated device between a slow speed mode and a power mode, an increase / decrease unit for increasing / decreasing the drive of the drive unit, a control valve operating unit for controlling the opening degree of the control valve, and a mode. Has setting means,
An operating means for operating the increasing / decreasing means and the control valve operating means, and an operation signal from the operating means including a mode setting signal from the mode setting means are inputted, and the increasing / decreasing means and the control valve are operated based on these input signals. And a control means for outputting a control signal to the means, and the opening degree of the control valve when the operation amount by the operation means is maximum while the drive of the drive means is maintained at a preset set amount in the slow speed mode. Is controlled in accordance with the manipulated variable so as to be maximum, and in the power mode, the opening of the control valve is maximized up to a fixed manipulated variable of the operating means, and the drive amount of the driving means is controlled in accordance with the manipulated value higher than Is controlled to be increased or decreased, and further, the slow speed mode is continuously shifted to the power mode.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, a case where the operating speed control device for hydraulically operating equipment according to the present invention is applied to a truck-mounted crane will be described.

FIG. 1 shows the schematic overall construction of a truck-mounted crane.

In the truck-mounted crane 1, a cargo box 2a is provided on a vehicle body 2, and a turning post 3 is rotatably mounted by a turning motor 15 (see FIG. 2) in front of the cargo box 2a of the vehicle body 2. . Boom 4 at the upper end of swivel post 3
Is provided.

The boom 4 is a multi-stage telescopic type, and can be telescopically moved by a telescopic cylinder 17 (see FIG. 2).
It is configured to be able to undulate by an undulating cylinder 5 disposed between the rotary post 3 and the turning post 3.

A winch 6 is provided at the base end of the boom 4, and a winch motor 16 (see FIG. 2) is used to wind up or pay out the wire 7 having a hook 7a.

Outriggers (not shown) are provided on the left and right sides of the front of the luggage box 2a of the vehicle body 2 so that the outriggers can be extended to the lateral sides of the vehicle body. Has been done.

2 and 3 show the main parts of the hydraulic circuit of the truck-mounted crane constructed as described above.

In FIG. 2, 11 to 14 are control valves which are connected to the swing motor 15, the hoisting cylinder 5, the winch motor 16 and the telescopic cylinder 17.

Each of the control valves 11 to 14 is constructed so as to gradually change from the neutral position to the left position or the right position with the movement of the spool, and the opening degree is gradually changed by the movement of the spool. ing.

One end of the spool is connected to one end of rods (control valve actuating means) 21 to 24 shown in FIG.

The rods 21 to 24 are configured to be movable left and right in FIG. 3 by switching the solenoid valves A1 to A4 and B1 to B4, and the spools are moved by the movement of the rods 21 to 24 to control the control valves. 11 to 14 can be switched and operated.

The other ends of the rods 21 to 24 are connected to differential transformers 21a to 24a. The differential transformers 21a to 24a move the rods 21 to 24, that is, the respective control valves 11 by moving the spools. ~ 14
(The opening degree of each control valve) can be detected.

Reference numeral 25 is a rod (increasing / decreasing means) which is movable left and right in FIG. 3 by switching the solenoid valves A5 and B5. One end of the rod 25 is connected to an accelerator for controlling the engine speed. , The other end of the differential transformer 25a is connected to the differential transformer 25a.
Thus, the moving position of the rod 25, that is, the number of revolutions of the engine by the accelerator operation can be detected.

The switching positions of the control valves 11-14 and the engine speed are detected by the differential transformers 21a-25.
The detection device is not limited to the device a, and another appropriate detection device may be used.

P is a pump (pressure oil supply source) operated by an engine linked through a power take-off device, and the pump P is changed by increasing or decreasing the engine speed by the accelerator operation.
It is configured to increase or decrease the amount of oil discharged from.

The operation of the swivel motor 15, the hoisting cylinder 5, the winch motor 16, and the telescopic cylinder 17, the swiveling of the swivel post 3, the operation of the winch 6, and the hoisting and telescoping of the boom 4 are performed by the operating device (operation) shown in FIG. Means) 30.

The operating device 30 is provided with two joystick levers 31 and 32 arranged vertically and a mode switching dial (mode setting means) 33.

The upper joystick lever 31 is constructed so as to operate the expansion and contraction of the boom 4 by tilting it in the vertical direction, for example, and extending the boom 4 by tilting it upward.
It is configured to operate the retracting of the boom 4 by tilting downward, and to operate the winding and unwinding of the wire 7 by the winch 6 by tilting left and right, and to wind the wire 7 by tilting left. , Tilt the wire 7 to the right
Can be operated.

The lower joystick lever 32 is constructed so that, for example, the boom 4 can be lifted and lowered by tilting in the vertical direction, and the boom 4 can be raised by tilting upward.
It is configured to operate the turning of the turning post 3 by tilting to the left and right, and to operate the turning of the turning post 3 by tilting to the left and right. By turning rightward, the turning post 3 can be turned clockwise.

The mode switching dial 33 is constructed so as to be switchable between a fine speed mode and a power mode, and the joystick lever 3 is operated by a control device which will be described later, based on the mode positions of the fine speed mode and the power mode.
By moving the rod 25 in accordance with the tilt angles of the rods 1 and 32, the number of rotations of the engine is controlled to control the amount of pressure oil discharged by the pump P, and each of the rods 21 to 24 is controlled.
By controlling the position of the spool, the opening of each of the control valves 11 to 14 is controlled.

FIG. 5 shows the relationship between the tilting angle of the joystick lever 31 and the expansion / contraction speed of the expansion / contraction cylinder 17 (that is, the expansion / contraction speed of the boom 4) in the power mode.

In the power mode, the control valve 14 is gradually increased in proportion to the tilt angle of the joystick lever 31 from the tilt angle X shown in FIG. 6 to the tilt angle Y (for example, about half the maximum tilt angle Z). Then, the control valve 14 is fully opened at the tilt angle Y. At this time, the number of revolutions of the engine is maintained at a slightly higher value from idling, whereby the expansion and contraction speed of the expansion and contraction cylinder 17 is proportionally amplified. That is, the control valve 14 is fully opened at a tilt angle Y that is about half the maximum tilt angle Z. Then, from the angle Y to the maximum tilt angle Z, the engine speed is increased in proportion to the tilt angle. As a result, the expansion / contraction speed of the expansion / contraction cylinder 17 rapidly increases as indicated by the solid line.

In the power mode, depending on the setting position of the mode switching dial 33 from MIN to MAX, characteristics such as the broken line and the one-dot chain line shown in FIG. 5 are exhibited. That is, the maximum value at each set position (the maximum expansion / contraction speed at the maximum tilt angle Z) also changes. In other words, in the power mode, when it is desired to reduce the maximum number of revolutions of the engine to prevent noise during nighttime work or the like, the mode switching dial 33 may be set to an arbitrary MID position or MIN position. As a result, the noise caused by driving the engine can be suppressed and the operation can be performed quietly.

FIG. 7 shows the relationship between the tilt angle of the joystick lever 31 and the expansion / contraction speed of the expansion / contraction cylinder 17 in the slow speed mode.

In the case of the slow speed mode, the control valve 14 gradually opens in proportion to the tilt of the joystick lever 31 from the tilt angle X to the maximum tilt angle Z shown in FIG.
Then, the control valve 14 is fully opened. At this time, the rotation speed of the engine for adjusting the discharge amount of the pressure oil from the pump P is maintained at a slightly higher value from idling, and as a result, the expansion / contraction speed of the expansion / contraction cylinder 17 is increased in proportion to the tilt angle.

Here, also in the above-mentioned slow speed mode, the telescopic cylinder 1 is moved according to the rotational position of the mode switching dial 33.
The expansion and contraction speed of 7 is increased and decreased.

The mode switching dial 33 is in the low speed mode between θ0 ° and 30 ° as shown in FIG. 8. By adjusting the mode switching dial 33, the opening of the control valve as shown in FIG. Is controlled. That is, since only the control valve is opened and closed in the slow speed mode, the opening of this control valve corresponds to the expansion / contraction speed of the expansion / contraction cylinder 17.

The joystick lever 3 based on the displacement of the mode switching dial 33 in the slow speed mode shown in FIG.
The relationship between the tilt angle of 1 and the control valve opening is obtained based on, for example, the relational expression shown in the flowchart of FIG.
The CPU 52, which will be described later, performs arithmetic processing.

Here, the calculation processing by the CPU shown in FIG. 10 will be described. In step S1, it is judged whether or not the tilt angle of the joystick lever 31 is Y or more. If the tilt angle is Y or less, Proceed to step S2 to perform arithmetic processing.

If the tilt angle of the joystick lever 31 is Y or more in step S1, step S
At 3, it is determined whether or not θ is 5 ° or more. If it is within 5 °, the process proceeds to step S2 to perform the arithmetic processing.

If θ is 5 ° or more in step S3, the process proceeds to step S4 and arithmetic processing is performed.

By the above processing, the control shown in FIG. 9 is performed in the slow speed mode. That is, if the position of the mode switching dial 33, that is, θ changes,
Calculation processing is performed at any time, and the control valve 14 is operated based on the calculation result.
Is controlled.

Therefore, when the mode switching dial 33 is rotated to the power mode side, the opening degree of the control valve 14 is displaced according to the amount of the rotation operation, and subsequently the power mode is continuously switched. .

Further, the turning post 3 by the turning motor 15
, The operating speed of the winch 6 by the winch motor 16 and the hoisting speed of the boom 4 by the hoisting cylinder are controlled in the same manner as described above by operating the joystick levers 31 and 32 based on the mode of the mode switching dial 33.

This alleviates the shock at the time of switching,
It is possible to prevent the load from swinging due to the shock.

FIG. 11 is a block diagram showing the configuration of the control device 50.

In FIG. 11, 51 is an A / D converter to which each feedback signal, the voltage signal from the potentiometer of each joystick 31, 32, and the voltage signal from the potentiometer of the mode switching dial 33 are input.
2 is a CPU, 53 is a RAM, 54 is a ROM, 55 is an input / output port, 56 is a power supply circuit, 57 is a switch, and 58 is L.
ED, 59 is a numeral display, 60 is a watchdog timer for detecting abnormality, 61 to 70 are drive circuits, AS1
-AS5 and BS1-BS5 are solenoid valves A1-
A5 and B1 to B5 solenoids.

Next, the control device 50 configured as described above.
The operation of will be described.

First, the case where the mode switching dial 33 is set to the slow speed mode will be described.

Each joystick lever 3 according to work
When the 1, 2 are tilted, the voltage signals of the joystick levers 31, 32 are input to the CPU 52 as operation signals via the A / D converter 51.

The CPU 52 calculates the deviation between the feedback signal from the differential transformer 25a for detecting the rotation speed of the accelerator and the idling-up signal, and based on the deviation, when the preset dead zone is exceeded, the drive circuit 61 is operated. Alternatively, an operation signal is output to 62 and the solenoid A
Exciting S5 or BS5 to move the rod 25,
The speed of the accelerator is increased to a predetermined speed.

At the same time, the deviations between the feedback signals from the differential transformers 21a to 24a for detecting the opening degrees of the control valves 11 to 14 and the respective operation signals are calculated, and the dead zone preset based on the deviations is calculated. When the control signals 11 to 14 are moved by outputting an operation signal to each of the drive circuits 63 to 70 and exciting the solenoids AS1 to AS4 or BS1 to BS4 to move the rods 21 to 24,
Are controlled based on the above-mentioned arithmetic processing.

As a result, the amount of oil supplied to the swing motor 15, the hoisting cylinder 5, the winch motor 16, and the telescopic cylinder 17 is controlled. For example, the telescopic speed of the telescopic cylinder 17, that is, the telescopic speed of the boom 4 is as shown in FIG. Controlled by.

The above-described operation in the slow speed mode is performed when the mode switching dial 33 is at a fixed position. However, by rotating the mode switching dial 33 during the operation, the openings of the control valves 11 to 14 can be changed. , Mode switching dial 3
The calculation processing is performed at any time according to the rotation position of No. 3, and control is performed so that the relationship shown in FIG. 9 is established.

In this way, while the opening of the control valves 11 to 14 is controlled in the slow speed mode, the power mode described later is entered.

Next, the case where the mode switching dial 33 is in the power mode will be described.

Each joystick lever 3 according to work
When the 1, 2 are tilted, the voltage signals of the joystick levers 31, 32 are input to the CPU 52 as operation signals via the A / D converter 51.

The CPU 52 integrates the operation signals according to the operation signal having the largest voltage among the operation signals and the set position from MIN to MAX in the power mode of the mode switching dial 33, and calculates the difference between the operation signals. The deviation from the feedback signal from the dynamic transformer 25a is calculated, and when a preset dead zone is exceeded based on the deviation, an operation signal is output to the drive circuit 61 or 62 to excite the solenoid AS5 or BS5 to drive the rod 25. It is moved and the increase / decrease in engine speed is controlled via the accelerator.

On the other hand, each operation signal is corrected,
Deviations between these correction signals and the feedback signals from the differential transformers 21a to 24a for detecting the opening degrees of the control valves 11 to 14 are calculated, and when the preset dead zone is exceeded based on the deviations, each drive is driven. Circuit 63-70
To the solenoids AS1 to AS4 or BS1 to BS4 to move the rods 21 to 24 and control the opening of the control valves 11 to 14, respectively.

As a result, the amount of oil supplied to the swing motor 15, the hoisting cylinder 5, the winch motor 16, and the telescopic cylinder 17 is controlled. For example, the telescopic speed of the telescopic cylinder 17, that is, the telescopic speed of the boom 4 is as shown in FIG. Controlled by.

[0057]

As described above, according to the present invention, in the slow speed mode, the opening of the control valve is controlled according to the operation amount, and the power mode is continuously changed. The switching from the slow speed mode to the power mode can be smoothly performed without giving a large shock to the hydraulically-operated device, and in the case of the crane operation, it is safe without causing a shake of the load and has good operability.

[Brief description of drawings]

FIG. 1 is a side view showing a schematic overall configuration of a truck-mounted crane.

FIG. 2 is a hydraulic circuit diagram of a truck-mounted crane.

FIG. 3 is a hydraulic circuit diagram of a truck-mounted crane.

FIG. 4 is a perspective view showing an operation device.

FIG. 5 is a diagram showing the relationship between the tilt angle of the joystick lever and the expansion / contraction speed of the expansion / contraction cylinder in the power mode.

FIG. 6 is a diagram showing a tilt angle of a joystick lever.

FIG. 7 is a diagram showing the relationship between the tilt angle of the joystick lever and the expansion / contraction speed of the expansion / contraction cylinder in the slow speed mode.

FIG. 8 is a front view showing a mode switching dial.

FIG. 9 is a diagram showing a relationship between a tilt angle of a joystick lever and an opening degree of a control valve in a slow speed mode.

FIG. 10 is a flowchart showing a calculation process in the CPU in the slow speed mode.

FIG. 11 is a block diagram showing a configuration of a control device.

[Explanation of symbols]

 5 Lifting Cylinder (Hydraulic Actuator) 11-14 Control Valve 15 Swing Motor (Hydraulic Actuator) 16 Winch Motor (Hydraulic Actuator) 17 Telescopic Cylinder (Hydraulic Actuator) 30 Operating Device (Operating Means) 31, 32 Joystick Lever 33 mode switching dial (mode setting means) 50 control device (control means) P pump (pressure oil supply source)

Claims (1)

[Claims] 1. A control valve for controlling a hydraulically operated device operated by supply of pressure oil from a pressure oil supply source operated by drive means, an increase / decrease means for increasing / decreasing the drive of the drive means, and the control valve Control valve actuation means for controlling the opening degree of the hydraulic pressure control device, and mode setting means configured to switch the operation of the hydraulically actuated device between a slow speed mode and a power mode, and operate the increase / decrease means and the control valve actuation means. And operating means for inputting operation signals from the operating means including the mode setting signal from the mode setting means, and controlling means for outputting control signals to the increasing / decreasing means and the control valve actuating means based on these input signals. In the low speed mode, the operation of the drive means is maintained at a preset setting amount so that the opening degree of the control valve is maximized when the operation amount of the operation means is maximum. Controlled according to the amount, in the power mode to maximize the opening degree of the control valve until a certain operation amount of the operation means, a driving amount of said driving means to increase or decrease control correspondingly higher amount of operation,
Further, the operating speed control device for hydraulically operating equipment is characterized in that the mode is continuously shifted from the slow speed mode to the power mode.