JPS6035565B2 - hydraulic control valve device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic control valve device for controlling the flow of a large capacity main circuit with the flow of a controlled small capacity pilot circuit used in a hydraulic circuit.

Conventional hydraulic control valve devices of this type are pilot-operated systems that use the flow in the pilot circuit to control the flow in the main circuit, but they also have a single function of directional control, pressure control, or flow rate control. When constructing a hydraulic control circuit, a combination of large-capacity control valves with different functions is used. Furthermore, when systematizing the valve as an integrated valve, it is inconvenient because it requires the use of many different types of single-function valves, and the disadvantage that the integration increases the external size and also affects the price is unavoidable. In addition, as shown in, for example, Tokusei No. 48-73823, Tokukai Sho 48-86121, and Tokusei No. 49-3074, large flow control that operates according to the function of the pilot valve is also possible. Multifunction valves are also known.

In addition to the pilot flow rate detection orifice, these multifunction valves have an orifice for detecting the flow rate of the main flow in the part that controls the main flow, and the pressure difference that occurs in the orifice is fed back to the main control valve. The flow rate is adjusted, but with this type of control valve, if the main control flow rate is low, the pressure difference generated at the orifice will be too small and the accuracy of the control valve will deteriorate, so it is not suitable for small flow rate control. ,
When the controlled flow rate is large, the pressure difference at the orifice becomes large, and the minimum operating pressure difference during control, that is, the pressure loss as a control valve becomes large. Therefore, it is impossible to satisfy a wide range of control flow rates from small flow rates to large flow rates with just one control valve, and the disadvantage is that each control valve must be designed and adjusted individually according to the flow rate range used. The present invention seeks to eliminate the above-mentioned drawbacks, and its main purpose is to provide a flow path for the main control flow in a multifunctional hydraulic control valve device that controls the flow in the main circuit in a pilot-operated manner. An object of the present invention is to provide a hydraulic control valve device that can control the main circuit flow with high accuracy in response to the pilot flow rate over a wide control range from small flow rates to large flow rates without providing a fixed orifice for detecting the pilot flow rate. .

One of the specific objects of the present invention is to provide the above-mentioned hydraulic control valve device in which the main valve body can be displaced in response to the pilot flow rate even when the flow rate is small. Another specific object of the present invention is a hydraulic control valve device that can control up to a large flow rate by ensuring that the minimum operating pressure difference of the valve does not increase and remains a constant value even when the control flow rate becomes a large flow rate. The goal is to provide the following. Yet another specific object of the present invention is to incorporate a pressure compensation valve inside the main valve spool that maintains the differential pressure before and after the main circuit control section constant in both directions of the flow. The objective is to consolidate the through holes and oil passages for the compensation valve on the spool side, simplify the processing on the valve body side, and downsize the entire valve body. To achieve such an object, the hydraulic control valve device of the first invention of the present application has a spool-type main valve body, which is compressed by a main valve spring from both ends within the valve body to create a spring center type, by a pilot flow. In a system in which the flow in the main circuit is controlled by a pilot operation method by displacing the main valve spring against the main valve spring until the differential pressure generated before and after the pilot orifice is balanced with the spring force of the main valve spring, from the pilot boat. One end side receives the hydraulic pressure, and the other end side receives the hydraulic pressure from the external boat, and the pressure receiving area for the pilot pressure is equal on both end sides, and one end side receives the pilot pressure and is displaced in one direction. A first main control port that allows the external boat to pass through the supply boat at certain times, and a second main control port that allows the external boat to pass through the discharge boat when the other end side receives pilot pressure and is displaced to the other side. a main valve body having a main valve body symmetrically with respect to a neutral position; A main valve spring whose force changes are equal to each other and a main valve body are arranged coaxially, and a pressure compensating spring chamber is formed at one end side and a pressure valve chamber is formed at the pond end side, and the pressure compensating spring in the pressure compensating spring chamber acts as a pressure valve. First and second pressure compensation control ports are formed between the main valve body and are biased toward the chamber by a spring and are in series with the first and second main control ports, respectively, through an internal hollow portion. The pressure compensating valve and the supply boat are passed through the pressure valve chamber according to the displacement of the main valve body to one side, and the external boat is passed through the pressure compensation spring chamber, and the external boat is passed according to the displacement of the main valve body to the other side. The pilot passage is opened at a predetermined opening between the pilot boat and the external boat, and the pilot passage is bored in the main valve body so that the supply boat passes through the pressure valve chamber and the pressure compensating spring chamber. A pilot orifice that generates a pressure difference before and after the flow due to the flow, further, the pilot orifice is a fixed orifice, and the main valve spring is a cylindrical spring that acts when the pilot flow is small, and a cylindrical spring that acts after the pilot flow has increased to a certain extent. It is characterized by a combination of a circular sushi and a spring that act to increase the spring force as it swells, and as a result, the difference between before and after the pilot orifice can be adjusted without providing a fixed orifice in the flow path of the main control flow. The relationship between the main valve body control port is controlled in a wide control range from small flow rate to large flow rate according to the pressure, and the pressure difference before and after the main control port is always kept constant with a compact configuration. By flowing the main flow in proportion to the flow rate, pressure loss within the valve is prevented from increasing even at large flow rates.

Further, another specific object of the present invention is to be able to be constructed with only ordinary parts without using the special parts such as the disk and spring used in the first invention, and to have a small pilot flow. However, it is an object of the present invention to provide the above-mentioned hydraulic pressure control valve device in which the main valve body can be displaced in response to the flow.

Therefore, in the hydraulic control valve device according to the second aspect of the present invention, the pilot orifice is not simply a fixed orifice, but a pipe on the upstream side thereof.

The main valve spring is configured by a povet valve that opens when the pilot pressure reaches a certain pressure or more and then generates a differential pressure according to the pilot flow rate, and the main valve spring also closes when the pilot pressure reaches the cracking pressure of the povet valve. This valve is characterized by being constructed with only a cylindrical spring that is set so that the main valve body control port just begins to open at the same time.This allows the main flow to be controlled from the beginning of the pilot flow without using a spring. It has been made possible to do so. In the present invention, the main valve body responds even if the pilot flow rate is small, so
The main circuit flow can be controlled from a small flow rate range, and since no extra orifice is provided in the main flow path, there is no pressure loss due to it, and it is possible to control up to a large flow rate.

Furthermore, since the pressure compensating valve is incorporated into the main valve body spool, the through holes and oil passages therefor can be concentrated on the main valve body side, and it is also possible to simplify the machining on the valve body side. Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the first invention, and in the hydraulic control valve device of this embodiment, a supply boat 2 is connected to a pilot boat 38 to the valve body 1, and a supply boat 2 is also connected to a pilot boat 39. A discharge boat 3 is provided, and various parts to be described later are installed symmetrically with respect to both the supply and discharge boats as seen in the figure.

For convenience of explanation, parts installed on the left side will be suffixed with A or C in the rear figure number, and those installed on the right side will be suffixed with B or D. Unless there is a particular need, the left side configuration will be mainly described in detail. do. That is, the main valve body 5A that slides within the valve chamber 25A, which is suitable for the A boat 4A (B boat 4B) as an external connection boat that closes to the outside of the valve body, is arranged in the spring chambers 35A and 36A, respectively. A pilot passage 32A with a damping throttle 34A is created between the spring chambers and the valve chamber 25A by being compressed from above and below by a cylindrical spring 7A, a circular spring, and a spring 7C, and a cylindrical spring 6A, a circular cylinder, and a spring 6C.
, and the pilot passage 31A passing through the pilot aperture 33A.

Further, a pressure compensating valve body 8A is slidably inserted into the main valve body, and a pressure compensating valve spring 9 is disposed within the spring chamber 16A.
Pressure is applied at A to form a valve chamber 17A at the back of the valve. Also,
A valve chamber 18A surrounding the main valve body and conveying the valve body 1 to the supply boat 2 and a valve chamber 51A suitable for the discharge boat 3.
A main control port 19A is formed between the valve chamber 18A and the pilot boat 10A bored in the main valve body 5A, and a main control port 28A is formed between the pilot boat 15A and the valve chamber 51A, The pilot boat 10A is connected to a pilot passage 12A provided in the main valve body 5A, and the end of the passage is connected to the valve chamber 17A and the pilot boat 14A. Furthermore, the pilot passage 15
A is connected to the pilot passage 13A similarly provided in the main valve body 5A, and the end of the passage is closed to the spring chamber 16A and the pilot boat 11A, and the main valve body 5A is connected to the pilot passage 13A.
A valve chamber 24A that fits into the valve chamber 25A, and valve chambers 27A and 20A above and below the valve chamber 24A are provided. The valve chamber 24A
is conveyed to the valve chamber 23A of the pressure compensating valve body 8A, and the valve chamber 20
A and the valve chamber 21A of the compensation valve body and the pressure compensation control port 29A.
The valve chamber 26A of the compensating valve body is formed in the same way as the valve chamber 27A.
A pressure compensation control port 30A is formed. Furthermore, the valve chambers 23A, 21A and 26A are provided in the hollow portion 22 inside.
The pipes are connected to each other at A, and the spring chamber 36A can be freely connected to the outside. Pass the lotus through the cut port 37A. In order to describe the operation of this invention, the circuit of the pilot switching valve 40 shown in FIG. 1 will be described. The pump boat P of the valve 40 has a pilot boat 38, the tank boat T has a pilot boat 39, Boat A has pie.

The pilot boat 37B is also connected to the boat 8. According to the embodiment of the present invention described above, the pilot flow flowing in from the pilot boat 37A passes through the spring chamber 36A, the pilot throttle 33A, and the pilot passage 31A, and flows out from the A boat 4A, creating a pressure difference before and after the throttle. The pressure difference causes the main valve body 5A to be displaced toward the spring chamber 35A, and the main valve body occupies a position where the internal spring force and the pressure difference are balanced.

When the main valve body is in the neutral position shown in the drawing, the pilot boats 10A, 11A are closed, and as the main valve body is displaced, both boats are closed simultaneously, but at this time, the other pilot boats 14A, 11A are closed. 15A is blocked.

When the boats 10A and 11A close, the supply boat 2
The pressure oil flows into the valve chamber 17A via the boat 10A and the pilot passage 12A, presses the pressure compensating valve element 8A against the compensating valve spring 9A, and the control port 29A closes. Further, when the main valve body 5A is displaced, the control port 19A is closed and the pressure oil in the valve chamber 18A flows into the valve chamber 20A. When the oil pressure in the valve chamber increases, the pilot boat 11A of the main valve body
, the pressure oil flows into the spring chamber 16A through the same passage 13A, opens the control port A, and the pressure oil flows into the valve chambers 21A, 22A,
It flows out to A boat 4A via 23A and 25A. The pressure compensation valve body 8A controls the main flow of the control port 29A by occupying a position where the pressure difference between the valve chambers 18A and 20A is determined by the spring force of the spring 9A and the cross-sectional area of the compensation valve body. Next, when the pilot switching valve 40 is switched to cut off the pilot flow, the pressure difference across the pilot throttle 33A disappears, the main valve body returns to the neutral position by the force of both springs, and the control row 9A is blocked and closed. Main flow is blocked. Contrary to the above, when pilot flow is introduced from A boat 4A,
The pressure oil flows out to the boat 37A through the opposite path to that described above, and a pressure difference is generated in the pilot throttle 33A, one of which acts on the main valve body 5A from the spring chamber 35A and the other from the spring 36A. Then, the main valve body is displaced toward the spring chamber 35A side, and is placed in a position that is balanced with the spring force inside the main valve body. First, depending on this main valve body, the pilot boat 14A
, 15A closes at the same time and other pilot boats 10A
, 11A are cut off. When both the boats 14A and 15A close, the boat 15A closes the valve chamber 5 on the discharge boat 3 side.
1A, the pressure oil in the spring chamber 16A of the compensation valve body 8A is connected to the pilot passage 13A, the boat 15A, and the valve chamber 51A.
It is then opened to the discharge boat 3. Next, the pressure oil flowing from the pilot boat 14A through the same passage 12A into the valve chamber 17A and through the valve chambers 25A, 24A, 23A, 22A, 26A and into the valve chamber 27A causes the compensating valve body 8A to
The control port 30A is closed against the spring 9A. Furthermore, when the control port 28A opens according to the displacement of the main valve body, the pressure oil in the valve chamber 27A flows out into the discharge boat 3 through the valve chamber 51A, and the oil pressure in the valve chamber 27A decreases accordingly.
The pressure in the valve chamber 17A of the pressure compensating valve body 8A decreases, and the compensating valve body returns to its position by the spring force of the spring 9A. Therefore, the control port 30A opens and the pressure oil of the A boat is discharged from the boat 3. to flow out. In this case, as described above, the compensation valve body controls the pressure difference between the valve chambers 27A and 51A, and occupies a position determined by the spring force of the spring 9A and the cross-sectional area of the compensation valve body. , performs pressure compensation during flow rate control of the main valve body 5A. As previously mentioned, the pilot flow
When flowing from A to A boat 4A, the main flow flows from supply boat 2 to A boat 4A, and conversely when flowing from A boat 4A to boat 37A, the main flow flows from A boat 4A to discharge boat 3, and Since the pilot boat 10A or 14A closes before the control row 9A or 28A of the main valve body opens, the control port 2 of the compensation valve body first opens.
9A and 30A are closed, and then the control port 19A or 28A of the main valve body is closed, and then the control port 29A or 30A is closed to allow the main flow of pressure oil to flow, so there is a jumping phenomenon that occurs in normal flow control valves. does not occur. In addition,
Since it is equipped with a damping throttle 34A, the main valve body 5A
It is also possible to prevent the occurrence of vibrations.

Further, as mentioned above, due to the bilaterally symmetrical configuration of the parts, the above-described operation is equally valid on the right side.

The above-mentioned operation is to control the main circuit analogously by controlling the pilot circuit, and the principle thereof will be explained as follows.

The cylindrical springs 6A, 7A with a small spring constant and the cylindrical springs 6C, 7C with a large constant are selected as the displacement control springs of the main valve body 5A, and the former spring is pre-stressed and installed. The main valve body is brought to a neutral position, and in this neutral position, the latter spring does not apply spring force to the main valve body 5A, and the main valve body is displaced by hydraulic pressure to control the control row 9.
A, 28A is installed so that it acts immediately before the mouth closes.

In this case, by making the spring force of the circular sushi and springs 6C and 7C proportional to the square of the amount of extension, the total spring force becomes as shown in FIG. 2. That is, if the main valve body displacement is X, the main valve body control port opening is x, the amount of overlap of the control ports is h, the circular spring constant is kl, and the cylindrical spring constant is k3, then k3 is small, so The spring force F acting on the main valve body is F=kl・(x-h)212・k31×dkl. (x-h)2=kl·x2.

The pressure difference △p that occurs before and after the throttle 33A when the flow rate q flows through the pilot circuit is △p, where the throttle resistance is R.
= R・q2, and the main valve body balance formula is, if the main valve body cross-sectional area is A,
Since A.Δp=F=kl., the main valve body relation x is x; ノA'R/kl.q.

Moreover, the pressure difference Δpm between the control ports 19A and 28A of the main valve body 5A whose pressure is compensated by the pressure compensating valve body 8A is calculated by setting the spring constant of the pressure compensating valve spring 9A to k2, and the spring extension of the spring to X.
s, if the cross-sectional area of the pressure compensating valve body 8A is Ac, then △pm
= k2. x no △pm=K-q.

However, K is K=kf·k2·Xs/Ac and is called an amplification factor, and the main flow flow rate Q increases by k times in proportion to the pilot flow flow rate q.

Therefore, since the flow rate QT passing through the A boat 4A or the B boat 4B is the sum of the flow rate Q and the flow rate q, (
10K)q, and the flow rate q of the pilot circuit is proportional to the flow rate QT of the main circuit, and it is possible to control the main circuit analogously by controlling the pilot circuit as described above.

It goes without saying that the above explanation holds true regardless of whether the flow is from the supply boat to the A or B boat or from the A boat or B port to the discharge boat.
Next, FIG. 3 shows an embodiment of the second invention, in which, instead of the pilot throttle 33A of the embodiment shown in FIG. The flow was reversed, and the spring chamber 36A was opened again.
, 35A, except that only cylindrical springs 6'A and 7'A with large spring constants are arranged without providing any springs.
The structure is exactly the same as that of the previous embodiment.

The operation of this embodiment is similar to that of the previous embodiment, except that the povet valves 41A and 42A generate a pressure difference according to the pilot flow rate to displace the main valve body 5A, thereby controlling the king flow. , the pilot current is boat 37A
When the flow is from the A boat to the A boat 4A, the povet valve 41A is opened, and when the flow is in the opposite direction, the povet valve 42A is opened.

Pressure difference before and after each povet valve in these cases △
p is the Pobett valve cracking pressure △pc, and the constant is kq
Then, △p=△pc+kq·q, and as shown in FIG. 4, it is almost a straight line.

The main valve body 5A occupies a position that balances the pressure difference between the povet valves 41A and 42A and the spring force of the springs 6'A and 7'A, connects the control rows 9A and 28A, and connects the povet valves and the cylinder. As described above, the main flow rate can be made proportional to the pilot flow rate only by the spring.

Next, to further explain the functions of the valve device according to the present invention with reference to an example of use, the circuit shown in FIG. Boat P goes to supply boat 2 via pilot boat 38, and boat A goes to pilot boat 37.
As described above, port A and port B are connected to boat 37B, and tank boat T is connected to discharge boat 3 via boat 39, respectively.

Now, if the switching valve is switched to P-A and B-T, /・
On the A side, the pilot flow flows through the supply port 2, the pilot boat 38, the switching valve 40, the pilot boat 37A, and the spring chamber 36.
A, pilot throttle 33A, same passage 31A, A boat 4
On the B side, the flow flows from the B boat 4B to the discharge boat 3 in the opposite direction to the above-mentioned passage, displacing the main valve bodies 5A and 5B, respectively, and on the A side, the flow flows from the supply boat 2 to the A boat. 4A, and from the B boat 4B to the discharge boat 3 on the B side. In this case, since no other control valve is inserted into the pilot circuit, the pilot flow flows freely and the royal flow also flows freely along the aforementioned path. In addition, the switching valve is set to A-T.
, P-B, the king flow flows from the A boat 4A to the discharge boat 3 and from the supply boat 2 to the B boat 4B, just as before. Furthermore, in FIG. 5, where the circuit is configured as a switching and flow rate control valve, the pilot flow control valve 43A is installed in the pipe between the pilot boat 37A and the boat A of the pilot switching valve 40 shown in FIG. The same flow rate control valve 43B is inserted on the A side, and when the switching valve is switched to P-A and B-T, the pilot flow is transferred from the supply port 2 on the A side to the A boat 4A via the illustrated route. , on the B side, it flows from the B boat 4B to the discharge boat 3 via the illustrated path, but on the A side, the pilot flow rate is controlled to q by the pilot flow rate control valve 43A, so the main flow rate is K・q, and the A The flow rate from the boat 4A to the actuator is (10K)q, and since the pilot flow passes through the check valve side of the flow rate control valve 43B on the B side, the king flow also flows freely from the B boat 4B to the discharge boat 3. .

Then, when the switching valve is switched to A-T and P-B,
On the A side, the pilot flow flows freely into the discharge boat 3;
On the B side, the flow rate to the actuator is controlled by the flow control valve 43B as described above, and the flow rate to the actuator is (10K)q. At this time, the pilot flow control valves are both included in the meter-in, so the main flow is controlled by the final tine.
It is also possible to control the main flow with a meter-out by controlling the flow rate that returns. Furthermore, to explain the circuit configuration as a switching and pressure reducing valve illustrated in FIG. 6, the pilot boat 3 illustrated in FIG.
A pilot pressure reducing valve 45A is inserted in the conduit between the switching valve A boat 7A and the switching valve A boat, and at the switching valve positions P-A and B-T, the pressure of the A boat 4A is set to the pressure reducing valve setting on the A side. If the pressure is lower than the pressure, the pilot flow flows from the supply boat 2 to the A boat 4A via the illustrated path, and the main flow flows from the supply boat 2 to the pilot 4A depending on the pilot flow rate, but the pressure of the A boat is lower than the pilot pressure reducing valve. 45A
When approaching the set pressure, the reduced pressure flow rate decreases, the main flow flow rate also decreases, and the pressure of the A boat 4A is reduced to the set pressure.

On the B side, the pilot flow flows freely from the B boat 4B to the discharge boat 3 via the path shown, so that the main flow also flows from the B
Flows freely from boat 4B to discharge boat 3. next,
When the switching valve is switched to the A-T and P-B positions, A,
The pilot flow is free on both sides of B, and the main flow also flows freely from the A boat 4A to the discharge boat 3 and from the supply boat 2 to the B port 4B. Furthermore, the circuit configuration as a reef valve illustrated in FIG. Relief valves 46A and 46B are arranged, and by switching the switching valve, it operates as a switching valve similarly to the illustrated example in FIG. 1, but the pressure of A boat 4A is lower than the set pressure of pilot relief valve 46A When the pressure rises, the pressure oil is relieved as a pilot flow through the pilot passage 31A and other routes from the pilot relief valve 46A to the pilot boat 39 and then to the discharge boat 3, and the resulting pressure difference at the pilot throttle 33A causes the main valve body 5 to
A is displaced and the main flow is relieved from the A boat 4A to the discharge boat 3, and when the pressure decreases, the pilot flow stops and the main valve body 5A is brought to the neutral position by the cylindrical spring 6A, the circular ring, and the spring 6C. Return to the position, stop the flow of reef to the discharge boat 3, and reduce the pressure of the A boat 4A to the relief valve 46A.
Maintain the set pressure.

Needless to say, the above-described operation also holds true for the B side.

Furthermore, each of the pipes between the pilot boats 37A and 37B of the pilot circuit and the boats A and B of the pilot switching valve 40 shown in FIG. In FIG. 8, in which 43AB is arranged, when the gate valve 40 is in the neutral position, the A side is fully closed, and the relief valve 46B is activated on the B side, and the B boat 4B is closed as in the example of FIG. pressure oil is relieved to the discharge boat 3, and its pressure does not rise above the relief valve setting pressure.

Now, when the switching valve 40 is switched to P-A and B-T, the flow rate of the pilot circuit on the A side is adjusted to the flow rate q by the flow rate control valve 43A, so the flow rate K・q is adjusted from the supply boat 2.
flows into the A boat 4A, and when the flow rate flowing out from the A boat 4A becomes less than (10K)q, the pressure reducing valve 45A
works to reduce the pressure in the A boat 4A to the pressure reducing valve setting pressure, and on the B side, the pilot flow freely flows from the B boat 4B to the discharge boat via the check valve of the flow control valve 43B, so the main flow also flows from the B boat. 4B flows freely to the discharge boat 3. Next, when the switching valve is switched to A-T and P-B, the pilot flow freely flows from the A boat 4A to the discharge boat 3 via the pressure reducing valve 45A and the flow control valve 43A check valves on the A side. , the main flow also flows freely from the A boat 4A to the discharge boat 3, and on the B side, the pilot flow is adjusted to the flow rate q by the flow rate control valve and flows to the B boat 4B, so the main flow also flows from the supply boat 2 to the flow rate K.
q flows to the B boat 4B, and the pressure is applied to the relief valve 46B.
When the pressure becomes higher than the set pressure, it goes off. Since the bottom flow or the entire amount is discharged from the relief valve 46B to the discharge boat 3, the flow rate of the main flow also decreases accordingly, and the pressure in the B boat 4B does not become higher than the relief valve setting pressure. Also,
In each of the above embodiments, as shown in FIGS. 9 and 10, the supply boat 2 and the discharge boat 3 are provided through the valve body 101, and the support plate 10 is engaged with another valve laterally.
2, the valve body is connected to the actuator by providing an A boat 4A, a B boat 4B, and a bolt hole 107 on the side of the valve body. Mounting bolt holes 108 and each pilot boat 37A, 37B, 38, 39 shown in FIG.
Alternatively, instead of the above-mentioned through-bolt fastening shown in FIG. By performing the above configuration, an inter-valve circuit configuration may be created in which piping or manifolds are omitted.
As described above, the present invention allows main flow control to be performed by retaining all the functions of the pilot circuit by configuring the pilot circuit with the pilot switching valve alone or in combination with other pilot operated valves. More specifically, a pilot circuit having the functions required for the main control circuit is constructed by roughly combining four-capacity pilot valves with various single functions, and a small flow of the circuit is used to control the pilot flow. Since a large-capacity main control valve can be controlled with a pressure compensation function over a wide control range from startup, the main circuit can be controlled to fulfill the same function as the pilot circuit with a single main control valve, and the main circuit can be controlled to satisfy the same function as the pilot circuit. Since the control valve has multiple functions in one unit and can perform functions according to the functions of the pilot circuit, it is only necessary to deploy small pilot valves according to the function with one type of large-capacity control valve, making it easy to integrate. Even when systematized as a valve, it can be configured with a small number of types, the main control valve can be integrated with the actuator stand to achieve the purpose, and the pressure compensation valve is built into the main valve body spool. The through holes and oil passages can be concentrated on the main valve body side, simplifying the machining of the valve body side, and therefore, the valve body is small, lightweight, and inexpensive.

[Brief explanation of the drawing]

Fig. 1 is a configuration explanatory diagram showing a longitudinal cross-sectional view of an embodiment of the first invention with a pilot switching valve circuit attached, Fig. 2 is a cylinder and circular sushi, a spring force and displacement relationship curve diagram, and Fig. Fig. 4 is a diagram showing the flow rate and pressure characteristic curves of the Pobet valve, and Figs. FIG. 9 is a configuration explanatory diagram in which a longitudinal cross-sectional view of an embodiment of the invention is accompanied by different examples of pilot circuits, FIG. 10th
The figure is a front view of the previous figure, Figure 11 is an A-A blind view of Figure 9,
FIG. 12 is a side view showing another example of the valve-to-valve connection. 1... Valve body, 2... Supply boat, 3
...Discharge boat, 4A, 4B...A, B boat, 5A, 5B...Main valve body, 8A, 8B...
Pressure compensation valve body, 33A, 33B... Pilot throttle, 3
4A, 34B... Damping aperture, 40...
...Pilot switching valve. Figure 1 Figure 2 Figure 4 Figure 12 Figure 3 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11

Claims (1)

[Scope of Claims] 1. A spool-type main valve element which is made up of a spring center type by being compressed by main valve springs from both ends within the valve body, is compressed by the differential pressure generated before and after the pilot orifice due to the pilot flow. The flow of the main circuit is controlled by a pilot operation method by displacing the main valve against the spring force until it is balanced with the spring force of the pilot port 37A.
One end side receives the hydraulic pressure from the external port 4A, and the other end side receives the hydraulic pressure from the external port 4A, and the pressure receiving area for the pilot pressure is equal on both end sides, and the pilot pressure is received on the one end side and transferred to the other side. External port 4 when displaced
A first main control port 19A that communicates A with the supply port 2, and a second main control port 28A that communicates the external port 4A with the discharge port 3 when the other end face receives pilot pressure and is displaced to the other side. The main valve body 5A is symmetrical with respect to the neutral position, and the main valve body 5A is set to the neutral position when there is no pilot pressure, and the main valve body 5A is set to the neutral position when there is no pilot pressure, and the main valve body 5A is set to the neutral position, and the main valve body 5A is set to the neutral position and the main valve body is A main valve spring whose spring force changes are equal to each other and a main valve body 5A are arranged coaxially, and a pressure compensation spring chamber 16A is formed at one end and a pressure valve chamber 17A is formed at the other end. first and second pressure compensation controls that are biased toward the pressure valve chamber 17A by a pressure compensation spring 9A inside and are connected in series to the first and second main control ports, respectively, via an interior hollow portion 22A; Mouth 29A, 3
a pressure compensating valve 8A that forms 0A with the main valve body 5A;
As the main valve body 5A is displaced to one side, the supply port 2 is communicated with the pressure valve chamber 17A, and the external port 4A is communicated with the pressure compensating spring chamber 16A. A pilot passage 12A is bored in the main valve body 5A so as to communicate the port 4A with the pressure valve chamber 17A and the supply port 2 with the pressure compensation spring chamber 16A.
, 13A, pilot port 37A and external port 4A
and a pilot orifice that communicates with the main valve at a predetermined opening degree to generate a differential pressure before and after the pilot flow due to the pilot flow, and the pilot orifice is a fixed orifice 33A, and the main valve spring is activated when the pilot flow is small. A hydraulic control valve device characterized in that it is a combination of cylindrical springs 6A, 7A and conical springs 6C, 7C which act after the pilot flow increases to a certain extent and increase the spring force with deflection. 2. The spool-type main valve element is pressed by main valve springs from both ends within the valve body to form a spring center system, and the differential pressure generated before and after the pilot orifice due to the pilot flow balances the spring force of the main valve spring. In this device, the flow of the main circuit is controlled by a pilot operation method by displacing the main valve against the main valve spring, and the pilot port 37A
One end side receives the hydraulic pressure from the external port 4A, and the other end side receives the hydraulic pressure from the external port 4A, and the pressure receiving area for the pilot pressure is equal on both end sides, and the pilot pressure is received on the one end side and transferred to the other side. External port 4 when displaced
A first main control port 19A that communicates A with the supply port 2, and a second main control port 28A that communicates the external port 4A with the discharge port 3 when the other end face receives pilot pressure and is displaced to the other side. The main valve body 5A is symmetrical with respect to the neutral position, and the main valve body 5A is set to the neutral position when there is no pilot pressure, and the main valve body 5A is set to the neutral position when there is no pilot pressure, and the main valve body 5A is set to the neutral position, and the main valve body 5A is set to the neutral position and the main valve body is A main valve spring whose spring force changes are equal to each other and a main valve body 5A are arranged coaxially, and a pressure compensation spring chamber 16A is formed at one end and a pressure valve chamber 17A is formed at the other end. first and second pressure compensation controls that are biased toward the pressure valve chamber 17A by a pressure compensation spring 9A inside and are connected in series to the first and second main control ports, respectively, via an interior hollow portion 22A; Mouth 29A, 3
a pressure compensating valve 8A that forms 0A with the main valve body 5A;
As the main valve body 5A is displaced to one side, the supply port 2 is communicated with the pressure valve chamber 17A, and the external port 4A is communicated with the pressure compensating spring chamber 16A. A pilot passage 12A is bored in the main valve body 5A so as to communicate the port 4A with the pressure valve chamber 17A and the supply port 2 with the pressure compensating spring chamber 16A.
, 13A, pilot port 37A and external port 4A
and a pilot orifice which communicates at a predetermined opening degree with the pilot orifice to generate a differential pressure before and after the pilot flow due to the pilot flow, and the pilot orifice is opened when the pilot pressure on the upstream side of the pilot orifice reaches a certain pressure or more. After that, poppet valves 41A and 42 generate a differential pressure according to the pilot flow rate.
A, and the main valve spring is a cylindrical spring 6'A, 7 set so that the main control port of the main valve body just starts to open when the pilot pressure reaches the cracking pressure of the poppet valve. 1. A hydraulic control valve device comprising only 'A.