JP2003148408A - Control device of hydraulic actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost by eliminating the need of forming a notch of a specified form in a main spool of a switching control valve according to the work characteristic of a hydraulic actuator and making the switching control valve in common to facilitate stock management. SOLUTION: This control device of a hydraulic actuator includes a pilot- operated switching control valve 32 for expanding and contracting a boom, which controls a boom expansion and contraction hydraulic cylinder 8, a remote operating device 70 for operating the switching control valve 32 for expanding and contracting the boom, and an arithmetic part 50 for storing the opening characteristic data of the main spool 21 of the switching control valve 32 for expanding and contracting the boom, which is set according to the operating characteristic of the boom expansion and contraction hydraulic cylinder 8, and outputting a pilot operation signal to the switching control valve 32 for expanding and contracting the boom according to an operation signal from the remote operating device 70 and the opening characteristic data of the main spool 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a hydraulic actuator that operates a spool of a switching control valve according to the characteristics of the hydraulic actuator.

[0002]

2. Description of the Related Art In hydraulically driven mechanical equipment, when controlling a hydraulic actuator, the main spool of a switching control valve of the hydraulic actuator is moved to switch the oil passage and the opening area of the oil passage is changed. The flow rate of pressure oil is controlled to control the operating characteristics and operating speed. The operation of the main spool of the switching control valve is performed by a machine-side operation manually operated by using an operation lever connected via a link or a remote operation operated by a remote controller.

[0003] Some hydraulically driven mechanical equipment is provided with a plurality of hydraulic actuators and these hydraulic actuators must be interlocked with each other. For example, in a vehicle-mounted crane 1 as shown in FIG. 4, a column 6 is rotatably provided on a base 4 having an outrigger 2, and a boom 7 that extends and contracts at the upper end of the column 6 is pivotally supported. It is supported. The column 6 is provided with a winch 11, which guides the wire rope 12 to the tip of the boom 7 and hooks it on a hook 13 for hanging load via a pulley (not shown) at the tip of the boom 7. Hook 1 by turning
3 is suspended from the tip of the boom 7.

In this crane 1, as a hydraulic actuator for rotating the column 6, extending and retracting the boom 7, and hoisting and lowering the winch 11, a turning hydraulic motor 5, a boom extending and retracting hydraulic cylinder 8, A boom hoisting hydraulic cylinder 9 and a winch hydraulic motor 10 are provided, and these need to be controlled to operate according to the content of the work. The turning hydraulic motor 5, the boom expanding / contracting hydraulic cylinder 8, the boom hoisting hydraulic cylinder 9, and the winch hydraulic motor 10 are transferred from a hydraulic pump (not shown) driven by an engine of the vehicle via a switching control valve device 3. It operates by supplying pressure oil. The amount of pressure oil discharged from the hydraulic pump increases as the engine speed increases and decreases as the engine speed decreases.

The switching control valve device 3 is a boom expansion / contraction switching control valve for controlling the actuators of the boom expansion / contraction hydraulic cylinder 8, the boom up / down hydraulic cylinder 9, the swing hydraulic motor 5, and the winch hydraulic motor 10, respectively. Three
2, boom up / down switching control valve 33, turning switching control valve 3
1 and a winch switching control valve 34 are connected to each other, which is a multi-connection valve device capable of machine-side operation and remote operation. When the crane 1 is operated on the machine side, the switching control valve device 3 is switched by the operation lever 14.

When the crane 1 is operated remotely, the switching control valve device 3 is normally operated by a remote controller 70 as shown in FIGS. 6 and 7. For the remote controller 70, a boom hoisting tact switch 71 for selecting the hoisting operation of the boom 7, a winch hoisting up / down tactile switch 72 for selecting the hoisting and hoisting operation of the winch 11, and a telescopic operation of the boom 7 are selected. Boom telescopic tact switch 73 for
A swing tact switch 74 for selecting the swing operation of the boom 7 to the left and right, and a speed lever 75 for controlling the speed of each operation of the crane 1 are provided.
The selection signals of the hydraulic actuator and the pulling signal of the speed lever by operating the speed levers 1, 72, 73 and 74 and the speed lever 75 are, as shown in FIG.
Via the transceiver 30 from the arithmetic unit 5 of the switching control valve device 3
Sent to 0.

In response to this operation signal, the arithmetic unit 50 causes the boom expansion / contraction switching control valve 32 and the boom hoisting switching control valve 3 to operate.
3, turning switching control valve 31, winch switching control valve 34
And the accelerator control actuator 5
5 controls the rotation speed of the engine. The boom expansion / contraction switching control valve 32 has a main spool 35 built therein, and the main spool 35 includes left and right springs 36.
And is normally held in the neutral position. Main spool 3
One end of 5 is connected to the operation lever 14 via a link 15. A pilot piston 37 for switching the main spool 35 is formed at the other end, and a piston rod 38
An iron core 39 is provided at the tip of the. This iron core 39
Is a position detector 40 having a hollow cylindrical operating transformer.
Has been inserted inside.

The boom expansion / contraction switching control valve 32 is provided with proportional electromagnetic pilot valves 41L and 41R for controlling the pilot piston 37. The solenoids 42L and 42R of the proportional solenoid pilot valves 41L and 41R are
An operation signal is sent from each of the arithmetic units 50 via the digital / analog converters 51 and 52. In the proportional solenoid pilot valves 41L and 41R, the port E to which pilot pressure oil is supplied from the hydraulic pump is normally closed, and the port F for returning the hydraulic oil to the tank is normally open.
When a control current is input to L or solenoid 42R, left and right pilot spools 43L or pilot spools 4L
3R slides, and the opening amount of the E port can be controlled by the input current value. Therefore, the supply of pilot pressure oil to the left and right oil chambers 37L and 37R of the pilot piston 37 is controlled.

When pilot pressure oil is supplied to either one of the oil chambers 37L and 37R, the main spool 35 moves to the right or left to connect the service port B or the service port A to the pump port P. Therefore, the boom extension / contraction switching control valve 32 supplies pressure oil to the extension chamber 16 or the compression chamber 17 of the boom extension / contraction hydraulic cylinder 8 to extend / contract the boom extension / contraction hydraulic cylinder 8. At this time, the position detector 4
0 detects the amount of displacement of the pilot piston 37 and sends the detection data to the arithmetic unit 50 via the analog / digital converter 53. As a result, the displacement amount of the main spool 35 is fed back to the calculation unit 50.

The boom up / down switching control valve 33, the swing switching control valve 31, and the winch switching control valve 34 have the same structure as the boom telescopic switching control valve 32 (the same components are designated by the same reference numerals). Detailed description is omitted). However, the hydraulic actuators for boom extension / contraction hydraulic cylinder 8, boom hoisting hydraulic cylinder 9, turning hydraulic motor 5, and winch hydraulic motor 10 have different operations, volumes, and required work speeds, and thus have their own operation. Therefore, the main spools 35, 44, 45, and 46 of the boom expansion / contraction switching control valve 32, the boom up / down switching control valve 33, the swing switching control valve 31, and the winch switching control valve 34 have characteristics. The required pressure oil amount of each hydraulic actuator 8, 9, 5, 10 is different for each displacement amount.

Therefore, each hydraulic actuator 8, 9,
In order to operate 5, 10 at an appropriate working speed and improve the operability in crane work, each main spool 3
As shown in FIG. 8, 5, 44, 45, and 46 have the required opening amounts for the displacement amounts of the spools in accordance with the working characteristics of the hydraulic actuators 8, 9, 5, and 10. Notches 47A, 47B with different shapes
47C and 47D are formed.

These notches 47A, 47B, 47C,
The 47D smoothes the operation of the hydraulic actuators 8, 9, 5 and 10, and is indispensable especially when performing an inching operation that requires a fine operation. Therefore, the boom expansion / contraction switching control valve 32, the boom up / down switching control valve 33, the swing switching control valve 31, and the winch switching control valve 34 have different shapes as the main spools 35, 44, 45, 46. It was necessary to prepare a dedicated product in which the notches 47A, 47B, 47C, 47D were formed.

[0013]

However, when the main spool of the switching control valve is a dedicated product adapted to the working characteristics of the hydraulic actuator, it is necessary to replace the hydraulic actuator in order to change the stroke, thrust, etc. It is necessary to replace the main spool with one with a different notch shape. Therefore, it is necessary to re-notch the main spool or to newly create the main spool, which is troublesome, troublesome, and high in cost.

Further, when a plurality of hydraulic actuators are used, the switching control valve cannot be shared, and it is necessary to prepare various kinds of main spools, which makes inventory management difficult. The present invention is to solve the above-mentioned problems in a control device for a hydraulic actuator, and it is not necessary to form a notch of a specific shape on the main spool of the switching control valve in accordance with the working characteristics of the hydraulic actuator. An object of the present invention is to provide a control device for a hydraulic actuator that can be commonly used to facilitate inventory management and reduce costs.

[0015]

A control device for a hydraulic actuator according to the present invention comprises a pilot controllable switching control valve for controlling the hydraulic actuator, and a remote controller for operating the switching control valve of the hydraulic actuator. The opening characteristic data of the main spool of the switching control valve, which is set according to the operating characteristics of the hydraulic actuator, is stored, and the switching control is performed based on the operation signal from the remote controller and the opening characteristic data of the main spool of the switching control valve. The above problem is solved by providing the valve with a calculation unit that outputs a pilot operation signal.

In this hydraulic actuator control device,
The calculation unit outputs a pilot operation signal to the switching control valve based on the preset opening characteristic data of the switching control valve main spool in accordance with the operating characteristics of the hydraulic actuator, and the main spool of the switching control valve is opened to an appropriate opening amount. To obtain a proper amount of pressure oil that matches the operating characteristics of the hydraulic actuator. Therefore, it is not necessary to form a notch having a specific shape on the main spool in accordance with the operating characteristics of the hydraulic actuator.

When changing the hydraulic actuator to another hydraulic actuator having different operating characteristics, it is not necessary to change the notch shape of the main spool of the switching control valve.
It is only necessary to update the opening characteristic data of the main spool stored in the arithmetic unit. Even when using multiple hydraulic actuators with different operating characteristics, the same shape can be used for the main spool, so there is no need to prepare multiple types of main spools, so the switching control valve can be shared and inventory management Will be easier.

When the arithmetic unit stores the opening characteristic data of the main spool of the switching control valve as a function of the pulling amount of the speed lever of the remote controller, only the function is changed when updating the opening characteristic data. All you have to do is make the changes easier.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of a boom expansion / contraction switching control valve in a hydraulic actuator control device for a crane showing an embodiment of the present invention, and FIG. 2 is an explanation of the operation of the boom expansion / contraction switching control valve. 3 and 4 are diagrams showing functional expressions for controlling the hydraulic actuator of the crane. The configuration of the control device for the hydraulic actuator of this crane is the same as that of the conventional one, except that the shape of the spool of the switching control valve and the opening characteristic data of the spool are stored in the calculation unit and the operation is performed based on this data. Therefore, the same portions will be described with the same reference numerals with reference to FIGS. 4 to 7.

The vehicle-mounted crane 1 includes an outrigger 2
A column 6 is rotatably provided on a base 4 provided with
A boom 7 that extends and contracts is pivotally supported on the upper end of the column 6 so as to be able to rise and fall. The column 6 is provided with a winch 11, from which the wire rope 12 is attached to the boom 7.
Pull the pulley to the tip of the boom (not shown) at the tip of the boom 7.
The hook 13 is hung from the tip of the boom 7 by being hooked around the hanging load hook 13 via.

In this crane 1, as a hydraulic actuator for swinging the column 6, extending and retracting the boom 7, and hoisting and lowering the winch 11, a swivel hydraulic motor 5, a boom telescopic hydraulic cylinder 8, A boom hoisting hydraulic cylinder 9 and a winch hydraulic motor 10 are provided. The turning hydraulic motor 5, the boom expanding / contracting hydraulic cylinder 8, the boom hoisting hydraulic cylinder 9, and the winch hydraulic motor 10 are transferred from a hydraulic pump (not shown) driven by an engine of the vehicle via a switching control valve device 3. It operates by supplying pressure oil. The amount of pressure oil discharged from the hydraulic pump increases as the engine speed increases and decreases as the engine speed decreases.

The switching control valve device 3 is a boom expansion / contraction switching control valve for controlling the actuators of the boom expansion / contraction hydraulic cylinder 8, the boom up / down hydraulic cylinder 9, the swing hydraulic motor 5, and the winch hydraulic motor 10, respectively. Three
2, boom up / down switching control valve 33, turning switching control valve 3
1 and a winch switching control valve 34 are connected to each other, which is a multi-connection valve device capable of machine-side operation and remote operation. When the crane 1 is operated on the machine side, the switching control valve device 3 is switched by the operation lever 14.

When the crane 1 is remotely operated, the switching control valve device 3 is switched by the remote controller 70 shown in FIGS. 6 and 7. For the remote controller 70, a boom hoisting tact switch 71 for selecting the hoisting operation of the boom 7, a winch hoisting up / down tactile switch 72 for selecting the hoisting and hoisting operation of the winch 11, and a telescopic operation of the boom 7 are selected. Boom telescopic tact switch 73 for turning, and a turning tact switch 7 for selecting the left and right turning operations of the boom 7.
4. Speed lever 7 for controlling the speed of each operation of crane 1
5 are provided and each tact switch 71, 72, 7
As shown in FIG. 5, the selection signal of the hydraulic actuator and the pulling signal of the speed lever by operating the speed control levers 3, 74 and the speed lever 75 are, as shown in FIG. Is sent to the calculation unit 50.

In response to this operation signal, the arithmetic unit 50 causes the boom expansion / contraction switching control valve 32 and the boom hoisting switching control valve 3 to operate.
3, turning switching control valve 31, winch switching control valve 34
And the accelerator control actuator 5
5 controls the rotation speed of the engine. As shown in FIG. 1, the boom expansion / contraction switching control valve 32 has a built-in main spool 21 in which no special notch is formed, and the main spool 21 includes left and right springs 36.
And is normally held in the neutral position. Main spool 2
One end of 1 is connected to the operation lever 14 via a link 15. A pilot piston 37 for switching the main spool 21 is formed at the other end, and a piston rod 38
An iron core 39 is provided at the tip of the. This iron core 39
Is a position detector 40 having a hollow cylindrical operating transformer.
Has been inserted inside.

Further, the boom extension hydraulic cylinder switching valve 3
2 is provided with proportional electromagnetic pilot valves 41L and 41R for controlling the pilot piston 37. Solenoids 42L, 42 of proportional solenoid pilot valves 41L, 41R
An operation signal is sent to R from the arithmetic unit 50 via the digital / analog converters 51 and 52, respectively. In the proportional solenoid pilot valves 41L and 41R, the port E to which pilot pressure oil is supplied from the hydraulic pump is normally closed, and the port F that returns the hydraulic oil to the tank is always open, and the solenoid 42L or the solenoid 42R receives a control current. Is input, the left and right pilot spools 43L or 43R slide, and the opening amount of the E port can be controlled by the input current value. Therefore, the pilot piston 37
The supply of pilot pressure oil to the left and right oil chambers 37L and 37R is controlled.

When pilot pressure oil is supplied to either one of the oil chambers 37L and 37R, the main spool 35 moves to the right or left to connect the service port B or the service port A and the pump port P to each other. Therefore, the boom extension / contraction switching control valve 32 supplies pressure oil to the extension chamber 16 or the compression chamber 17 of the boom extension / contraction hydraulic cylinder 8 to extend / contract the boom extension / contraction hydraulic cylinder 8. At this time, the position detector 4
0 detects the amount of displacement of the pilot piston 37 and sends the detection data to the arithmetic unit 50 via the analog / digital converter 53. As a result, the displacement amount of the main spool 21 is fed back to the calculation unit 50.

The boom up / down switching control valve 33, the swing switching control valve 31, and the winch switching control valve 34 are also constructed in the same manner as the boom telescopic switching control valve 32, and all have special notches. Not built-in main spool (not shown) of the same shape. In the control device for the hydraulic actuator of the crane, the arithmetic unit 50 is adapted to match the operating characteristics of the hydraulic actuators of the boom telescopic hydraulic cylinder 8, the boom hoisting hydraulic cylinder 9, the swing hydraulic motor 5, and the winch hydraulic motor 10. Boom expansion / contraction switching control valve 32, boom up / down switching control valve 3
3, the expansion function formula A _{l of} the boom expansion / contraction hydraulic cylinder and the boom expansion / contraction hydraulic cylinder reduction function formula shown in FIG. 3 as opening characteristic data of the main spools of the swing switching control valve 31 and the winch switching control valve 34. A ₂ , a function formula B _{1 of} a boom hoisting hydraulic cylinder, a function formula B ₂ of a boom hoisting hydraulic cylinder, a swing function formula C of a swing hydraulic motor,
Hoisting function formula D _l of the hydraulic motor winch, winding Shimonoseki formula D ₂ of the hydraulic motor winch is stored.

When operating the crane 1, the remote controller 70
The boom hoisting tact switch 71, the winch hoisting up / down tact switch 72, the boom telescopic tact switch 73, and the swiveling tact switch 74 cause the boom 7 to be hoisted, the winch 11 being hoisted and unwound, the boom 7 being telescopic, or the boom 7 being swung. The turning operation to the left and right is selected and the speed lever 75 is pulled. Then, the selection signal of the hydraulic actuator and the pulling signal of the speed lever are used as operation signals from the remote controller 70 via the transmitter / receiver 30.
Is sent to the calculation unit 50.

The extension operation of the boom 7 will be described below as an example. The calculation unit 50 receives an operation signal from the remote controller 70,
As a required function formula, the extension function formula A _l of the boom extension hydraulic cylinder is calculated, the speed lever pulling amount is substituted into the extension function formula A _l to obtain the main spool displacement amount, and the boom extension amount is used based on this data. A pilot operation signal is output to the proportional electromagnetic pilot valve 41L of the switching control valve 32.

As a result, as shown in FIG. 2, the main spool 21 of the boom expansion / contraction switching control valve 32 moves to the right so as to obtain an appropriate opening amount, and the extension chamber 16 of the boom expansion / contraction hydraulic cylinder 8 is expanded. Supply an appropriate amount of pressure oil that matches the operating characteristics. The calculation unit 50 compares the value fed back from the position detector 40 with the output value of the operation signal,
When the operation amount of the boom expansion / contraction hydraulic cylinder 8 is insufficient with respect to the speed lever pulling amount, a correction signal is sent to increase the operation amount. When the operation amount is excessive, a correction signal is sent to decrease the operation amount. Let

The boom up / down switching control valve 33, the swing switching control valve 31, and the winch switching control valve 34 are also operated in the same manner as the boom telescopic switching control valve 32. Therefore, it is not necessary to form a special notch on any of the main spools in accordance with the operating characteristics of the hydraulic actuator.
Even when changing the hydraulic actuator to another hydraulic actuator with different operating characteristics, it is not necessary to change the notch shape of the main spool of the switching control valve, but simply by updating the opening characteristic data stored in the calculation unit. good.

Even when a plurality of hydraulic actuators having different operating characteristics are used, since the main spools having the same shape can be used, it is not necessary to prepare many kinds of main spools, and the switching control valve can be shared. , Inventory management becomes easy. Since the calculation unit stores the opening characteristic data of the main spool of the switching control valve as a function of the pulling amount of the speed lever of the remote controller, only the function needs to be changed when updating the opening characteristic data. Change work can be done easily.

[0033]

As described above, the control device for a hydraulic actuator according to the present invention does not need to form a notch having a specific shape on the main spool of the switching control valve in accordance with the working characteristics of the hydraulic actuator, and thus the switching control valve can be formed. Can be standardized to facilitate inventory management and reduce costs.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a boom extension / contraction switching control valve in a control device for a hydraulic actuator for a crane according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of an operation of a boom expansion / contraction switching control valve.

FIG. 3 is a diagram showing a functional expression for controlling a hydraulic actuator of a crane.

FIG. 4 is a configuration diagram of a crane.

FIG. 5 is a configuration diagram of a control device for a conventional hydraulic actuator.

FIG. 6 is a front view of a remote controller.

FIG. 7 is a side view of the remote controller.

FIG. 8 is an explanatory view of a shape of a spool of a conventional switching control valve.

[Explanation of symbols]

1 crane 3 Switching control valve device 5 Hydraulic motor for turning 6 columns 7 boom 8 Boom extension hydraulic cylinder 9 Boom undulating hydraulic cylinder 10 winch hydraulic motor 11 winches 14 Operation lever 15 links 21 Main spool 31 Switching control valve for turning 32 Boom telescopic switching control valve 33 Switching control valve for boom undulation 34 winch switching control valve 37 Pilot piston 40 position detector 41L, 41R Proportional solenoid pilot valve 42L, 42R solenoid 43L, 43R pilot spool 47A, 47B, 47C, 47D Notch 50 arithmetic unit 70 Remote control 71 Boom up / down tact switch 72 winch up / down tact switch 73 Boom telescopic tact switch 74 Swiveling Tact Switch 75 speed lever

Claims (3)

[Claims] 1. A pilot controllable switching control valve for controlling a hydraulic actuator, a remote controller for operating the switching control valve of the hydraulic actuator, and a switching control valve set according to the operating characteristics of the hydraulic actuator. Of the main spool opening characteristic data is stored, and based on the operation signal from the remote controller and the main spool opening characteristic data of the switching control valve, a computing section for outputting a pilot operating signal to the switching control valve is provided. Control device for hydraulic actuator. 2. When the hydraulic actuator is changed to a hydraulic actuator having different operating characteristics, the opening characteristic data of the main spool of the arithmetic unit is updated instead of changing the main spool of the switching control valve. 2. The control device for the hydraulic actuator according to 1. 3. The hydraulic pressure according to claim 1, wherein the arithmetic unit stores the opening characteristic data of the main spool of the switching control valve as a function of the pulling amount of the speed lever of the remote controller. Actuator control device.