JPS61192902A - Control device for hydraulic equipment - Google Patents

Abstract

PURPOSE:To enable the changeover from a remote control mode to a manual control mode to be accomplished quickly by bringing a pilot cylinder to its central position quickly when a signal is output for bringing the pilot cylinder to its central position so that a manual control can be put into practice. CONSTITUTION:As a control means 20 applied to a hydraulic equipment in a main unit 19, the control is given through a displacement of the pilot 15 of a directional control valve 6 within a oil hydraulic circuit. The pilot piston 15 is brought back to its central position by a control unit 30, and the positioning operation is stopped when an indicating signal reaches its set point, after that, it is held in a state where the directional control valve 6 can be manually positioned freely. Thereby, the changeover from a remote control mode to a manual control mode can be accomplished very quickly.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a control device for hydraulic equipment.

2. Description of the Related Art For example, a vehicle equipped with hydraulic equipment such as a hydraulically controlled crane is equipped with a remote control device so that the hydraulic equipment can be operated even at a location away from the vehicle. In this type of remote control device, a high-rod piston that drives the directional switching valve is disposed in the directional switching valve that controls hydraulic oil introduced into the operating section of the base machine. Then, a switch installed in the remote control mex selectively opens and closes multiple solenoid valves installed in the oil passages to the pilot piston and the crane at a distance from the vehicle. When operating the directional control valves manually, the remote control can open all the solenoid valves and set Gyro and Toviston in the neutral position. This is done by means of the sui and te inside the box, thereby allowing free movement of the tobiston (see, for example, Japanese Patent Application Laid-Open No. 57-9306).

Problems to be Solved by the Invention However, in the conventional hydraulic equipment control device described above, the pilot piston is positioned at the neutral position by switching from the remote control state to the manual control state KIff, IIK, remote control &, swivel and te operations. operation is performed, and the remote control is activated (C)
-k'X): When a signal to position the / to the neutral position is output, all solenoid valves open, and the piston receives a predetermined spring force and is positioned at the neutral position. The structure is as follows. Therefore, when the outside temperature is low and the viscosity of the hydraulic oil and lubricating oil in each part is high, the spring force alone will cause the piston to operate slowly, causing the directional control valve to follow the operating side. However, a problem arises in that it is not possible to quickly move to the neutral position.

Therefore, there is a risk that the mother machine may perform an operation that is not intended by the operator, and there is also a problem with safety.

Therefore, an object of the present invention is to provide a control device for hydraulic equipment that enables manual operation by using a toss ring and a switching valve.
When a signal to position the pilot cylinder in the neutral position is output, the pyro and toshi ring are quickly positioned in the neutral position, and the hydraulic system enables quick and safe switching from remote control to manual control. The purpose of the present invention is to provide a control device for equipment.

Means for Solving the Problems The configuration of the present invention includes a directional switching valve for switching the direction of hydraulic pressure supplied to a hydraulic circuit of a hydraulic device, and a directional switching valve connected to the directional switching valve for controlling the directional switching valve. a detection means for detecting the position of the pilot piston and outputting a position signal indicating the position; a position setting means for outputting an instruction signal for instructing; a control means for positioning the /f pilot piston according to a deviation between the position signal and the instruction signal; In response, the above instruction signal commands to position the above □ Iro and Tovisto in the neutral position, and when the deviation between the above position signal and the above instruction signal falls within a predetermined range from K. , a first means for stopping the control operation by the control means and thereafter freeing the movement of the /9 pilot piston; and a second means for canceling the stoppage of the control operation of the control means by the first means in response to the instruction signal. It is characterized in that it is equipped with means.

Function: This control system for hydraulic equipment allows the movement of the /#iro, toviston to be made free, and the directional control valve to be operated manually.
Therefore, when the position setting means performs an operation to position the piston at the neutral position, first, the control means responds to this by quickly moving the I9 pilot piston to the neutral position by hydraulic pressure. , As a result, when the deviation between the position signal and the instruction signal falls within a predetermined range,
The first means is actuated, and the restraining force exerted on the Toviston by the control means is now removed, making it possible to manually operate the directional control valve. In this way, once the switch from remote control to manual control has been carried out, the Gino and Ilot pistons can be moved by manual operation.
Even if the deviation between the position signal and the instruction signal becomes large again, the controller/stage does not control the position of the pilot piston due to the action of the first means. The state in which the operation of the control means is stopped by the first means is canceled by the second means in response to the operation of the position setting means. be done.

Example Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

FIG. 1 shows a system diagram of hydraulic equipment controlled by a hydraulic equipment control device 20 according to the present invention. The pressure control valve 1 is used to maintain a constant pressure in the oil passage 4 of the hydraulic oil sucked up from the tank 3 by the oil feed pump 2, and the pressure of the hydraulic oil whose pressure is regulated by the pressure control valve 1 is Via a directional valve 6 connected to a manually operated lever 5 through a channel 4, a hydraulic system (not shown) of a mother machine 19, such as a crane, is supplied. The return oil passage 7 communicates the mother machine 19 and the tank 3 via the directional switching valve 6.

Hydraulic oil passage 4 is Che, Kupal 28. It communicates with the main oil passage 10 via a pressure reducing valve 9, and the pressure of the main oil passage 10 is controlled by a pressure control valve 11.

The pressure is set by this pressure control valve 11, and three solenoid valves 12゜13.1 are arranged in series in the oil passage 10.
4 are connected. A p4 iro and toviston 15 are connected to the directional switching valve 6, and the directional switching valve 6, pyro and toviston 15 are moved together by a manual lever 5. One chamber 16 of the high rod piston 15 is connected to the oil passage between the normally closed solenoid valve 12 and the normally open solenoid valve 13, and the other chamber 17 is connected to the oil passage between the normally open solenoid valves 13 and 14. connected to the road. Further, the pressure receiving area of the chamber 17 is larger than the pressure receiving area of the chamber 16, for example, about twice as large. Normally closed solenoid valve 12 is solenoid 128
When energized, the normally open solenoid valve 13 is switched to the open position.
．． 14 are switched to the closed position when the solenoids 13f9 and 14B are energized, respectively. When solenoid valve 12 is on, solenoid valve 1
3; When 14 are in the OFF state, the chambers 16 and 17 are communicated with each other via the solenoid valve 13, and the piston 15 is free to move, so that the directional control valve 6 can be freely operated by the manual operating lever 5. Switching can be controlled. Solenoid valve 1
2 is off and both solenoid valves 13.14 are on, each of these solenoid valves 12°13.14 is z? In order to close the pilot oil passage 10, the pilot piston 15 is fixed in that position.

Further, in this state, the manual operation lever 5 cannot be used to switch the directional control valve 6. When the solenoid valves 12 and 13 are on and the solenoid valve 14 is off,
0 hydraulic oil flows into the chamber 16 of the toviston 15, while the hydraulic oil in the chamber 17 returns to the tank 3, so that /
- Toviston 15 moves to the left (in the direction of arrow A), and moves the directional control valve 6 to the left to switch to position 6A. In addition, when the solenoid valves 12 and 14 are on and the solenoid valves 13 are off, the hydraulic oil in the /4 pilot oil passage 10 is both in the chambers 16 and 17.
flow inside. However, as mentioned above, since the pressure receiving area of the chamber 17 is larger than that of the chamber 16, the piston 15 moves to the right (in the direction of arrow A'), and the directional control valve 6 moves to the right. direction and switch to position 6B. Furthermore, one end side 1 of the pilot piston 15
A position detector 18 is attached to 5& to detect the displacement of the pilot piston 15.

The position detector 18 is configured using, for example, a potentiometer, and outputs a position signal V whose level changes according to the displacement of the drum, pyro, and tobistone 15. The level of this position signal V is, for example, /f according to the movement of the /4 pilot piston 15. When the tobiston 15 is in the center position, it is 12V, and the level increases as it moves leftward, and # as it moves rightward. 1 lowest, /f ilot piston 15
It is set so that a voltage is generated depending on the position of the

The hydraulic equipment control device 20 includes a position setting device 22 including an operating lever 21, a position signal V,
and the instruction signal VIN.
A control unit 30 controls the opening and closing of the solenoid valves 12 to 14 to position the pilot piston 15 at the position indicated by , a position signal V, and an instruction signal V□N.
40 for controlling switching between the remote control mode by the control unit 30 and the manual control mode by the manual operating lever 5 in response to the instruction signal VIN<.

The position setting device 22 is made up of, for example, a potentiometer, and outputs an instruction signal VtNt- corresponding to the position of the operating relay 4-21. Turn the operating lever 21 clockwise (in the direction of arrow C).
The movement is set so that the movement in the counterclockwise direction (direction of arrow C) corresponds to the movement of the direction switching valve 6 in the left and right directions.

Then, the position setting device 22 instruction signal V□9 is applied to the operating lever 2.
For example, when 1 is rotated clockwise to the maximum position, %
4V, 12V when in the neutral position, 20V when rotated counterclockwise to the maximum position, and changes in between depending on the rotation position.

FIG. 2 shows a circuit diagram of the hydraulic equipment control device 20. As shown in FIG. Here, the control unit 3o is a circuit unit for performing feedback control using the position signal v1 so that the /4 pilot piston 15 is positioned at the position indicated by the instruction signal VIN. ) Control signals V, , Vbe Vd based on the control calculation results performed within 3G are output. Control signals V, , Vb.

vdFi, solenoids 14S, 13S and 12S, respectively
The position of the Ginodylot piston 15 is controlled by this K, and the directional control valve 6 can be controlled to a desired state. The circuit configuration for performing feedback control to position the master piston 15, that is, the directional control valve 6, at a desired position in response to the position signal V and the instruction signal vXN is well known, and therefore will not be described herein. , control unit) 300, detailed illustration of the circuit configuration will be omitted.

Next, the switching control unit 40 will be explained.
Q1 to Q6 are transistors, D
1 to D4 are diodes, and C1 to C4 are voltage comparators whose outputs are open collector deaf. A positive electrode of a battery (not shown) is connected to the terminal 41, and a terminal voltage U is applied thereto.

A circuit voltage vce obtained by stabilizing the voltage of the battery by a voltage stabilizing circuit (not shown) is applied to the terminal 42, and position signals V, V, are applied to the terminals 43 and 44. and an instruction signal V are applied, respectively. Voltage comparator ClIC! , the level of the instruction signal vxN is V,
)V□H) A rounding window converter/4'lator circuit 45 is configured to detect whether or not the voltage is within the range of Vz. The value of voltage v1 * V B is the value of resistor R1e R
By adjusting the value of x*Rs, the window comparator circuit 45 determines whether the rail of the instruction signal V□ has reached a predetermined level LoK for instructing the Norilot piston 15 to be positioned in the neutral position. The value is set to such a value that it can be detected with an accuracy of .

Therefore, only when V becomes >VI or >VI, the level of the voltage v3 at the connection point of each output of the voltage comparators C1 and C becomes "H".

Voltage comparator C! *C4 also constitutes a window comparator circuit 46, and this window comparator circuit 4
6 is designed to discriminate the level of the position signal v2. The reference voltages for level discrimination in the quindocon/quantizer circuit 46 are a voltage v4 at the non-inverting input terminal of the voltage comparator C3, a voltage V4 at the inverting input terminal of the voltage comparator C4,
Only when Va > Vy > Vs O, the potential at the connection point of each output of the voltage comparators C3+C4 becomes "H" level.

Butterfly, resistor 1111 to the inverting input terminal of voltage comparator C4
A voltage dividing circuit 47 consisting of R1m is connected, and the collector of a transistor Qs whose emitter and rear end are grounded is connected via a resistor its9, and the level of the voltage V is the same as when the transistor Q3 is off. In this case, voltage divider circuit 47
When the transistor Q3 is on, the output level is approximately the ground level.

On the other hand, a resistor R is connected to the non-inverting input terminal of the voltage comparator C3.
A voltage dividing circuit 48 consisting of @ * R1° is connected, the collector of a transistor Q4 whose emitter is connected to the terminal 42 is connected via a resistor R14, and a transistor Q! whose emitter is grounded is connected. collector is connected.

Therefore, the level of voltage v4 is the same as transistor Q2eQ4.
are both off, the output level L4 of the voltage dividing circuit 48
When only transistor Q3 is on, it is approximately at the ground level, whereas when only transistor Q4 is on, it is approximately at the level of vcc.

The transistor Q2 is turned on when the level of the voltage v3 becomes rLJ, and the transistor Q1 is turned off.

Transistor Q3 is a quindo converter f-lator circuit 46
When the output type /E
(It turns on when it becomes J level and transistor Q5 turns on.

Next, the operation of the nine switching control unit 40 shown in FIG. 2 will be explained.

Since the remote control operation is executed by the lever 21, the level of the instruction signal V is either vIN>Vl or v
xN<v! , the level of the output voltage v3 of the window controller circuit 45 is rLJ, so the transistor Q1 is off and the transistor Q2 is on. As a result, the level of voltage v4 becomes approximately equal to the ground level. With and ζ, the level of the position signal vF changes between a value that is about 1 to 2 V higher than the ground potential and a value that is about 1 to 2 V lower than the power supply voltage VCC in the normal operating range of the /9 pilot piston 15. The position detector 18 is designed to do so. Therefore, when transistor Q2 is in the on state, v,
>v4, so the output level of voltage comparator C3 is rL
”, and the level of the output voltage v6 also becomes rLJ. Therefore, since the transistor Qs is turned off, the transistor Q6 is also turned off, and the anodes of the illumination diodes D3 and D4 connected to the collector of the transistor Q6 are at ground level. The cathodes of these diodes DJ, D4 are connected to the output transistors Q7-Qll, which are provided in the control unit 30, corresponding to each solenoid 148, 138.

Therefore, when transistor Q6 is off, it does not interfere with the operation of each output transistor Qy-Qa. However, the solenoids 12B to 14 of each solenoid valve 12 to 14
S operates according to the calculation results of the control unit 30, and the positioning operation of the pilot piston 15 in accordance with the operation of the lever 21 is feedback-controlled as described above.

Pyro, set the position of Tobiston 15 to the neutral position.

As a result, in order to switch to manual operation using the manual operation lever 5, the lever 12 is moved so that the level of vlN becomes L6.
When the above operation is performed, the window controller circuit 45 first responds to this by turning off the transistor Q2. In this state, the level of output voltage v6 is “L”.
'', transistors Qs, Q4, and Qs are all off, so the voltage v4. The level of v, is the level L4 determined by each voltage dividing circuit 48.47.
+L5. By the way, level L4 * L
gFi, voltages Vl, and V2 are set to be equal to each other. Therefore, even if the level of the instruction signal WIN becomes Lo, unless v4>v,>v, the level of the output voltage v6 will remain the same. remains at "L".

Therefore, even if the level of the instruction signal VIN increases, until the position detector 18 detects that the position of the pilot piston 15 has reached the neutral position, the position of the pilot piston 15 is determined by the control unit l'30. V
Feedback control is carried out so that the force = v2. In this way, when V4)v, )y, the output voltage v6
When the level of is at rHJ, the transistor Q6 is turned on, and the output transistors Q7-Ql are locked in the off state. As a result, the solenoid valve 12 is controlled by the control unit t l' 30
The solenoid valves 13 and 14 are in the OFF state, and the Toviston 15 is free to operate, and the directional control valve 6 can be manually operated by the manual operation lever 5. becomes.

When the level of the output voltage v6 becomes "H", the transistors Qs and Q4 are also turned on, and the voltage v4 becomes approximately equal to the power supply voltage Vcc, while the voltage vs becomes equal to the ground potential. As a result, even if the level of the position signal vF from the position detector 18 changes by manually operating the directional control valve 6, the position signal V! The level of is the voltage v at this time
41 vs , and the level of the output voltage v6 of the Wintoco//4 lator circuit 46 is maintained at the "H" level during the manual control mode described above.

That is, in response to the level of the instruction signal V increasing, the control unit y) 30 controls the control unit 30 until vIN=vF.
)/41 Return the position of Toviston 15 to the neutral position, and when it is determined that ■□, = v, stop the positioning operation of Toviston 15 by control unit 30, and thereafter , the directional control valve 6 is held in a state where it can be freely positioned manually. Therefore, since the level of the instruction signal v0 becomes L6, the operation of the control unit is immediately stopped, and
Compared to conventional devices in which the toviston 15 is placed in its neutral position by, for example, spring force alone, the toviston 15 can be moved to its neutral position much more quickly. As a result, switching from remote control mode to manual control mode is quickly performed. This is particularly effective for quickly switching when the outside temperature is low and the oil viscosity is high and the hydraulic mechanism operates slowly. In this way, if the control mode is switched quickly regardless of the outside temperature, problems such as the mother machine performing the desired operation during the switching will not occur, and safety will be improved. is also significantly improved.

In the manual control mode, the lever 21 is actuated, and the level Lo of the instruction signal VIN changes so that VlN>Vl or V
When lN<Vl, the level of the output voltage v3 of the window comparator circuit 45 becomes rLJ, and the transistor Q
2 is turned on, the level of output voltage v6 becomes rL again.
J and Nashi, transistor Q3.

Qs and Qa are all turned off. As a result, the control mode is switched to a remote control mode by operating the lever 21, and the solenoids 12S to 148 are driven based on signals from the control unit 30.

It should be noted that it will be easily understood from the description based on the above embodiments that the present invention can be widely applied to control devices for various hydraulic equipment including cranes.

Effects According to the present invention, as described above, when switching the control mode of hydraulic equipment from the remote control mode to the manual control mode, it is possible to realize extremely quick switching even when the outside temperature is low, and therefore the switching is easy. This provides an excellent effect of effectively preventing runaway of the hydraulic equipment that occurs in the hydraulic equipment during the transition period.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the configuration of a hydraulic system equipped with a hydraulic equipment control device according to the present invention, and FIG. 2 is a circuit diagram of the hydraulic equipment control device shown in FIG. 5... Manual operation lever, 6... Directional switching valve, 12゜13.14... Solenoid valve, 12g, 13S, 14S...
・Solenoid, 15.../Parameter piston, 18
...Position detector, 19...Mother machine, 20...Hydraulic equipment control device, 21...Operation lever, 22...Position setting device, 30...Control unit 2)%40... Switching control unit. Patent applicant: Diesel Kiki Co., Ltd. Agent: Patent attorney: Masatoshi Takano Figure 1

Claims (1)

[Claims] 1. Detection of a directional switching valve for switching the direction of hydraulic pressure supplied to the hydraulic circuit of hydraulic equipment, a pilot piston connected to the directional switching valve for controlling the directional switching valve, and the position of the pilot piston. a detection means for outputting a position signal indicating the position of the pilot piston, a position setting means for outputting an instruction signal for indicating the set position of the pilot piston in conjunction with a setting member for remote control, and the position signal and the instruction. a control means for positioning the pilot piston according to a deviation from the signal; and a control means for positioning the pilot piston at a neutral position in response to the position signal and the instruction signal; a first means for stopping the control operation by the control means when a deviation between the signal and the instruction signal falls within a predetermined range, and thereafter allowing free movement of the pilot piston; and a second means for canceling the stoppage of the control operation of the control means by the first means.