JPS62188805A - hydraulic control device - Google Patents

Abstract

PURPOSE:To equalize the expanding speed and the contracting speed by supplying pressure oil to a bottom side chamber of a cylinder through a large-diameter orifice, supplying same to a rod side chamber through a small-diameter orifice, and supplying the whole discharge of a pump to one circuit system when the other circuit system is stopped. CONSTITUTION:One out port 11 of a compensator valve C is connected to one circuit system X and the other out port 12 is connected to the other circuit system Y. A large-diameter orifice 31 and a small-diameter orifice 32 are formed on a direction switching valve. Pressure oil is supplied to a bottom side chamber 44 of a cylinder S through the large-diameter orifice 31, and supplied to a rod side chamber 45 through the small-diameter orifice 32. Thus, the expanding speed and the contracting speed of a cylinder S of one circuit system X can be equalized so that operability can be improved. Furthermore, when one circuit system X is stopped, the whole discharge of a pump can be supplied to the other circuit system Y.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a hydraulic control device for driving an actuator of one circuit system and an actuator of the other circuit system with one pump. The present invention relates to a device used when supplying a constant controlled flow rate to a power steering device and supplying surplus flow rate other than that to an actuator of another working machine system.

(Prior Art) As this type of attire, the one shown in FIG. 3 has heretofore been known.

This conventional device has a priority valve 1 on the pump P.
are connected. And this priority valve 1
One out port 2 is connected to the directional switching valve 4 that controls the cylinder 3 of the - side circuit system, and the other out port 5 is connected to the directional switching valve 7 that controls the actuator 6 of the other circuit system. is connected to.

Now, when pump P is driven, priority valve 1
functions to supply a constant controlled flow rate of the discharge d'' flow rate to the directional control valve 4 side, and supply a surplus flow rate other than this control flow rate to the directional control valve 7 side. When the cylinders 3.6 are stopped, the pressure oil supplied to each directional control valve 4.7 is returned to the tank T via the drain passage 8.9.

(Problem to be solved by the wooden device) In the conventional configuration as described above, the flow rate supplied to the cylinder 3 via the directional control valve 4 is constant, and moreover, the flow rate supplied to the cylinder 3 via the directional control valve 4 is constant, and Since the volumes of the rod side chambers 3b are different, their expansion speed and contraction speed are different. For this reason, the operator's operating feeling differs between the extension side and the contraction side, resulting in a problem of poor operability.

Further, even when the cylinder 3 is stopped, the control flow b: cannot be routed to the other circuit system, so there is a problem that the entire discharge amount of the pump cannot be used effectively.

An object of the present invention is to make the expansion speed and contraction speed of the cylinders in one circuit system the same, and when the cylinders in one circuit system are stopped, the entire pump discharge amount is transferred to the other circuit system. The goal is to be able to turn the situation around.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the following configuration.

In other words, the compensator valve connected to the pump,
One circuit system is connected to the other circuit system, a directional control valve is connected to the downstream side of the compensator valve in one circuit system, and one of the ports of this directional control valve is connected to the compensator valve. The introduction port is
The relevant switching 5? The directional control valve is configured to close when it is in the neutral position, and the directional control valve is formed with a large diameter orifice and a small diameter orifice, and an actuator port that communicates with the large diameter orifice is connected to the bottom side chamber of the cylinder, and the small diameter orifice is Connecting actuator port to low 2
In addition, the pressure on the upstream side of the orifice is introduced into one pilot chamber of the compensator valve, and the pressure on the downstream side of the orifice is introduced into the other pilot chamber. At the same time, when the directional control valve is in the neutral position, the other biloft chamber of the compensator valve is communicated with the tank, and the port on the side communicating with the other circuit system is almost fully opened.

(Operation of the present invention) This IJI is configured as described in section 2, so pressure oil is supplied to the bottom side chamber of the cylinder of one circuit system via the large diameter orifice, and the small diameter orifice is supplied to the loft side chamber. Pressure oil is supplied via the orifice.

Therefore, the flow rate per unit time supplied to the bottom side chamber is greater than the flow rate supplied to the loft side chamber.

Furthermore, when the directional control valve of one circuit system is kept in the neutral position and the cylinder is stopped, its inlet port is closed, and the port of the funpensator valve that communicates with the other circuit system is almost fully open IE. Become. Therefore, almost the entire amount of the pump discharge amount can be supplied to the other circuit system.

(Effects of the present invention) According to the device of the present invention, the expansion speed and the contraction speed of the cylinders in one circuit system can be made the same, so the operability is very improved.In addition, the cylinders in one circuit system can be stopped. When you are doing
Since almost the entire discharge amount of the pump can be supplied to the other circuit system, the entire flow amount can be used effectively.

(Embodiment of the present invention) Fig. 1 is a circuit diagram of an embodiment of the present invention, in which a pump P is connected to the pump port 10 of the compensator valve C, and one out port 11 of the compensator valve C is connected to one of the out ports 11 of the compensator valve C. Connect to the direction switching block PV of circuit system X,
The out port 12 of the other power is connected to the other circuit system Y.

Then, as shown in FIG. 2, the direction switching valve tv and the relief valve R of the above-mentioned fume vent converter valve C1, one of the circuit systems X, are integrated into the valve body A, and then the valve body A The configuration of is explained below.

The convencator valve C has both ends of its piston body 13 facing a pilot chamber 14.15, and a spring 16 is provided in the pilot chamber 15. Due to the action of this spring 16, when the piston body 13 is in the normal position, the spool end on one pilot chamber 14 side comes into contact with a plug 17 provided to close the pilot chamber 14. In addition, in the normal position, the annular enclosure 1 formed on the piston body 13 is
The pump bow 10 and one out port 11 communicate through the XP 118, and the pump port 10
Communication between the outport 12 and the other outport 12 is cut off.

Further, in the piston body 13, a through hole 19 is formed adjacent to the annular groove 18;
Regardless of the moving position of the piston body 13, it is always in communication with one out port 11, and also communicates with the one parrot chamber 14 through a damper orifice 20 formed in the piston body 13.

The one out port 11 communicates with the introduction port 21 of the directional control valve (2) described above, and solenoids 23, 24 are provided at both ends of the spool 22 of the directional control valve (V). The spool 22 is switched by being excited.

The center of the spool 22 thus constructed has a first annular groove 2.
5, and a second and third annular groove 26 is formed on the outer side of the first annular groove 25 and is always in communication with the actuator ports a and b.
．． 27, and both ends of the spool 22 face the drain chamber 28, 29, and this drain chamber 2
B, 2S are communicated with the tank T via the drain port 30.

Further, a large-diameter orifice 31 is formed between the first annular groove 25 and the second annular groove 26, and the large-diameter orifice 31 penetrates in a direction perpendicular to the axis of the spool 22. A similar small-diameter orifice 32 is formed between the third annular groove 27 and both orifices 31 and 32.
Each of them communicates with the introduction bow 21 via oil holes 33 and 34. However, when the spool 22 is in the neutral position shown, both orifices 31.32 remain closed in line with the closure 35.36 on the valve body A side.

Further, the communication passage 37 formed in the valve body A is closed by the land portion 38.3S formed in the spool 22 when the spool 22 is in the neutral position t shown in the figure. The pilot chamber 15 is always communicated via a pilot port 40.

In the spool 22, oil holes 41 and 42 are formed on the outer side of the third annular groove 27, and the oil holes 41 and 42 penetrate in a direction perpendicular to the axis of the spool 22.
．． 42 is formed along the axis of the spool 22.
It communicates via. When the spool 22 is in the neutral position shown, the oil hole 41 crosses the communication path 37 and the pilot port 40, and the oil hole 42 opens into the drain chamber 29, so that the pilot chamber 15 is connected to the drain chamber 29. It communicates with

Therefore, when the directional control valve V is maintained at the neutral position shown in the figure, the oil discharged from the pump P flows from the pump port 10 of the convencator valve C to the annular groove 18 formed in the piston body 13 to the directional control valve V. It flows into a flow path called the introduction port 21 of the. However, the directional control valve ■ is in the neutral position t shown in the figure.
When the introduction port 21 is closed, the pressure inside the flow path increases.
and is guided to one pilot chamber 14 of the convencator valve C via the damper orifice 20. At this time, the other pilot chamber 15 of the funbensator valve C
is connected to tank T via pilot port 40 → oil hole 41 + oil passage 43 → oil hole 42 → drain chamber 29 → drain port 30, so the pressure difference between both pilot chambers 14 and 15 is very large. Become. For this purpose, the piston body 13
moves against the spring 16, causing the annular groove 18 to be wide open toward the other out port 12.

Therefore, when the directional control valve (1) is held in the neutral position as described above, the entire amount of oil discharged from the pump P is supplied to the other circuit system Y via the other out port 12.

When the solenoid 24 of the directional control valve V is excited to move the spool 22 to the left in FIG. 2 from the above state E;, in other words, when the directional control valve V is switched to the left position in FIG. 1, It will look like this:

That is, when the spool 22 moves to the left in FIG.
First, the oil hole 42 is closed, so the pilot port 40
Communication between the drain port 30 and the drain port 30 is cut off. At the same time, the introduction bow (21) of the directional control valve V is inserted into the first annular groove 24.
-> Oil passage hole 33 -> communicates with one opening 37a of communication passage 37 via large-diameter orifice 31. Further, the other opening 37b of the communication path 37 communicates with the pilot port 40, and the third annular groove 27b formed in the spool 22.
It communicates with actuator port a via.

Therefore, the pressure oil that has passed through the compensator valve Ct-i is transferred from the introduction port 21 of the switching valve ■ to the first annular groove 24 to
The oil is guided to the other pilot chamber 15 via the oil passage hole 33 → large-diameter orifice 31 → communication path 37, and also flows into the bottom side chamber 44 of the cylinder S connected to one circuit system X from the actuator bow) a. .

When the pressure oil flows as described above, the pressure on the upstream side of the enlarged diameter orifice 31 is introduced into one pilot chamber 14 of the compensator valve C, and the pressure on the upstream side of the orifice 31 is introduced into the other pilot chamber 15. The pressure on the downstream side, that is, the load pressure of the cylinder S is introduced.

Therefore, the piston body 13 of the compensator valve C
The pressure in one pilot chamber 14, the pressure in the other pilot chamber 15, and the spring force of the spring 16 are
They will maintain a position that balances each other. In this balanced position, the amount of overlap between both sides of the annular groove 18, one out port 11, and the other out port 12 is controlled.

For example, as the load pressure of one circuit system X increases, the pressure of the other parrot chamber 15 also increases, which tends to cause the piston body 13 to move leftward in FIG. 2. When the piston body 13 tends to move leftward in this manner, the amount of overlap between the annular groove 18 and one out port 11 increases, but the amount of overlap between the annular groove 18 and the other out port 12 decreases.

In this way, the necessary control flow rate is secured in one circuit system X, and the bottom side chamber 4 of the cylinder S concerned is
The flow rate supplied to 4 is also controlled by a large diameter orifice 31.

Reference numerals 46 and 47 in the figure indicate annular notches formed on both sides of the annular groove 18 of the piston body 13.
This is for finely adjusting the amount of overlap between 8 and out ports 11 and 12.

When the solenoid 23 of the directional control valve (2) is energized to move the spool 22 to the right in FIG. 2, and the directional control valve (2) is switched to the right position in FIG. 1, the following occurs.

That is, when the spool 22 moves to the right in FIG.
First, the oil hole 41 is closed, so the pilot port 40
Communication between the drain port 30 and the drain port 30 is cut off. At the same time, the introduction port 21 of the directional control valve ■ is connected to the first annular groove 24.
-> Oil passage hole 34 -> Communicates with the other opening 37b of the communication passage 37 via the small diameter orifice 32. Further, one opening 37a of the communication path 37 is connected to a second opening 37a formed in the spool 22.
It communicates with the actuator port b via the annular groove 26. The communication passage 37 also communicates with the other pilot chamber 15 of the compensator valve C.

Therefore, the pressure oil that has passed through the compensator valve C is guided to the other pilot chamber 15 via the introduction port 21 of the switching valve ■→the first annular groove 24→the oil passage hole 34→the small diameter orifice 32→the communication passage 37. At the same time, it flows into the rod side chamber 45 of the cylinder S connected to one circuit system X from the actuator port b.

The function of the compensator valve C in this case is the same as in the above case in which the directional control valve (2) is switched to the left position.

As mentioned above, when supplying pressure oil to the bottom side chamber 44 having a large pressure receiving area of the cylinder S, the large diameter orifice 31
Since the small-diameter orifice is opened when supplying pressure oil to the rod side chamber 45, which has a small pressure-receiving area, the expansion speed and contraction speed of the cylinder S can be made the same. Due to reasons.

In other words, since the flow rate Wffl passing through the large-diameter orifice 31 is relatively larger than the flow rate passing through the small-diameter orifice 32, the flow rate supplied to the bottom side chamber 44 is correspondingly higher than the flow rate supplied to the rod side chamber 45. becomes more than

Further, the differential pressure generated before and after the large-diameter orifice 31 is open and when the small-diameter orifice 32 is open is different. In other words, when the large-diameter orifice 31 is open, the differential pressure is smaller, so
The differential pressure in the pilot chambers 14, 15 of the damper valve C also becomes smaller, and the piston body 13 is moved by the spring 1'8.
Due to this action, it tends to move to the left in Figure 2. Therefore, when the large-diameter orifice 31 is opened to supply pressure oil to the bottom side chamber 44, the controlled flow rate supplied to one circuit system X increases.

When supplying pressure oil to the bottom side chamber 44 in this way,
Since the amount of control waves determined by the relationship with the other circuit system Y increases, in combination with the control of the flow rate through the orifice described above, the supply to the bottom side chamber 44! The amount i becomes larger than the supply Q%f to the rod side chamber 45, and the expansion speed and contraction speed of the cylinder S can be made the same.

[Brief explanation of drawings]

Drawing Section 1.2 shows an embodiment of this invention 1, in which Fig. 1 is a circuit diagram, Fig. 2 is a sectional view, and Fig. 3 is a conventional circuit diagram. C... Compensator valve, P... Bonn 7',
11.12...Out port, X...one circuit system, Y...other circuit system, ■...direction switching block f,
T...Tank, 14.15...Pilot room, 2
1... Introduction port, a, b... Actuator port, 31... Large diameter orifice, 32... Small diameter orifice, S... Cylinder, 44... Bottom side chamber,
45...Rod side chamber.

Claims (1)

[Claims] Connect one circuit system to the other circuit system to the compensator valve connected to the pump, connect a directional valve to the downstream side of the compensator valve in one circuit system, and connect the port of this directional valve. Among them, the introduction port connected to the compensator valve is configured to close when the switching valve is in the neutral position, and the directional switching valve is formed with a large diameter orifice and a small diameter orifice. When switched, the actuator port communicating with the large-diameter orifice is connected to the bottom side chamber of the cylinder, the actuator port communicating with the small-diameter orifice is connected to the rod side chamber, and one pilot chamber of the compensator valve is connected to the bottom side chamber of the cylinder. , the pressure on the upstream side of the orifice is guided, and the pressure on the downstream side of the orifice is guided to the other pilot chamber,
A hydraulic control device configured to communicate the other pilot chamber of the compensator valve with the tank and substantially fully open the port communicating with the other circuit system when the directional control valve is in the neutral position.