JPS6035566B2 - 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, Tsubaki Publication No. 48-73823, Japanese Patent Application Publication No. 48-86121, and Japanese Patent Application Publication 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 multi-function valves have an orifice for detecting the flow rate of the main flow in the part that controls the flow, and the pressure difference that occurs at 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 in the OJ is too small and the accuracy of the control valve deteriorates, so it is not suitable for small flow rate control. On the other hand, 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 not possible to satisfy a wide range of control flow rates from small flow rates to large flow rates with a single control valve, so each control valve is designed individually according to the flow rate range used.
The disadvantage of having to make adjustments is unavoidable. 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. Another specific object of the present invention is to provide a function for switching the direction of the differential pressure of the main control port applied to both ends of the pressure compensating valve according to the direction of the pilot flow, without requiring the main valve spool to have the function of switching the direction of the differential pressure applied to both ends of the pressure compensation valve. By providing a switching valve, the construction of the main valve spool and the valve body around it is simplified, and
The oil passage switching valve has a coaxial structure with the pressure compensating valve to avoid increasing the size of the 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 internal oil chamber of the valve body when the valve body is in use; The main valve body has two main control ports symmetrically with respect to the neutral position, and the main valve body can be set to the neutral position when there is no pilot pressure, and the main valve body can be moved in both directions when the main valve body is displaced from the neutral position. A main valve spring whose spring force changes with respect to the body displacement stroke are equal to each other, a pilot orifice that runs at a predetermined degree between the pilot boat and the external boat and creates a differential pressure before and after it due to the pilot flow, and a slider inside the valve body. The valve is movably arranged and supported in a spring center manner by a pressure compensating valve spring so that an equal spring force acts on displacement from its neutral position, and the hydraulic pressure of the internal oil chamber is applied to one end and the other end. A pressure compensating valve is configured to receive the hydraulic pressure of the external boat with equal pressure receiving areas, and has a concave groove closed to the internal oil chamber formed on the outer periphery, and a pressure compensating valve is configured to receive the hydraulic pressure of the pilot boat on one end side. , the other end is coaxially disposed on the outer periphery of the pressure compensating valve so as to receive the hydraulic pressure of the external boat, and is loosely attached to the inner oil chamber together with both shoulders of the concave groove on the outer periphery of the pressure compensating valve. A pair of pressure compensation control ports are formed through the pilot boat, and when one end receives the hydraulic pressure of the pilot boat and is displaced in one direction, one of the pressure compensation control ports is connected to the pressure oil supply boat and the other is closed. , a concave groove on the outer periphery of the pressure compensating valve body is arranged so that when the other end receives the hydraulic pressure of the external boat and is displaced to the other end, the other pressure compensating control port is connected to the discharge boat and one side is closed. an oil passage switching valve having a pair of switching oil passage closures symmetrically provided, the pilot orifice being a fixed orifice, and the main valve spring being a cylindrical valve that acts when the pilot flow is low. It is characterized by a combination of a circular sushi that acts after the pilot flow has increased to a certain extent and increases the 1 imitation force as it swells, and a 1 imitation force. The opening degree of the main valve body control port can be controlled in a wide control range from small flow rate to large flow rate according to the differential pressure before and after the pilot orifice without providing a fixed orifice in the main valve body spool shape and main valve body. By using a pressure compensating valve to always keep the pressure difference before and after the main control port constant without complicating the surrounding oil passages and openings, and by allowing the main flow to flow in proportion to the degree of darkness, the valve can be used even in large flow conditions. This is to prevent the pressure loss inside from becoming large.

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. Therefore, in the hydraulic control valve device of the second invention of the present application, the pilot orifice is configured with a simple fixed orifice. Without,
It is constituted by a povet valve that opens when the pilot pressure on the upstream side exceeds a certain pressure and then generates a differential pressure according to the pilot flow rate, and the main valve spring also has a povet valve whose pilot pressure reaches the cracking pressure of the povet valve. It is characterized by being constructed only with a cylindrical spring that is set so that the main valve body control port just starts to open when the main valve body reaches its final position. It is designed so that it can be controlled.

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, and since no extra orifice is provided in the main flow path, there is no pressure loss due to it. , it is possible to control up to a large flow rate range.

Furthermore, since the pressure compensation valve is combined with an oil passage switching valve and these are placed in the valve body separately from the main valve body, the oil passages and checkpoints around the main valve body are not complicated, and the main valve body spool shape It will also be simple. 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 46 to the valve body 1, and a supply boat 2 is also connected to a pilot boat 47. 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 will be suffixed with A or C, and those installed on the right will be suffixed with B or D. Unless there is a particular need, the left configuration will mainly be described in detail. do. That is, the main valve body 5 moves within the valve chambers 44A and 43A, which are suitable for the A boat 4A (B boat 4B) as an external connection boat that closes to the outside of the valve body.
A is compressed from both ends by a cylindrical spring 6A, a conical spring 60C, a cylindrical spring 7A, and a conical spring 7C disposed in the spring chambers 17A and 18A at both ends, and the main valve body is also A valve chamber 19A that closes to the valve chamber 44A and a valve chamber 20A that opens to the valve chamber 43A are bored to form a valve chamber 21A that closes both valve chambers to the spring chamber 18A.

In addition, the main valve chamber (internal oil chamber) 33 surrounds the main valve body.
A is drilled to form a control port 41A between the valve chambers 44A and a control port 42A between the valve chambers 43A. Next, a movable oil passage switching valve body 10A is disposed in the valve body, and a pressure compensating valve body 8A is inserted into the switching valve body so as to be super movable. Spring chambers 22A and 23A are formed by sliding engagement with the main body, and a guide 11A is provided in the chambers.
, 12A are inserted and their tips are brought into contact with both ends of the compensation valve body, and are pressed by pressure compensation valve springs 13A and 14A. A closing hole 30A is bored in the center of the oil passage switching valve body to communicate with the valve chamber 33A via the valve chambers 31A and 32A, and oil passage gates 38A and 35A are bored on both ends thereof, and the former 38A is a valve body. The latter passes through the chambers 37A and 36A to the supply boat 2, and the latter 35A passes through the valve chambers 28A and 27A to the discharge boat 3, and one end surface of both end surfaces thereof is located in the valve chamber 25A, so that the valve chamber is connected to the above-mentioned valve chamber. A pilot boat 45A, which is connected to the spring chamber 23A of the pressure compensating valve body through its pilot passage 24A, and whose end face is located in the valve chamber 26A, and the valve chamber is disposed in the valve body 1, and the spring chamber 23A, 18A to pilot passages 15A and 16A. The passage 15A is also branched to the main valve body spring chamber 17A, and a damping throttle 48A is disposed in the lotus passage, and a pilot throttle 9A is disposed in the passage 16A. In the center of the pressure compensating valve body, a control port 40A is connected to the oil passage switching valve 30A, and a control port 40A is connected to the oil passage closing port 35A, and a control port 39A is connected to the oil passage opening 38A at both shoulders. A concave groove 29A to be formed is turned, and the concave groove and the compensation valve spring chamber 22A fit together in the pilot passage 34A. In order to describe the operation of this embodiment, the circuit of the pilot switching valve 49 attached to FIG. 1 will be described.
A pilot boat 46 is connected to the pump boat P of No. 9, a pilot port 47 is connected to the tank boat T, a pilot boat 45A is connected to the boat A, and a pilot boat 458 is connected to the boat B. According to the embodiment of the first invention described above, the pilot flow flowing from the pilot boat 45A flows through the pilot passage 15A and the throttle 9.
A, same passage 16A, spring chamber 18A, valve chambers 21A, 19A
, 44A, and generates a pressure difference across the throttle, and at the same time flows from the pilot passage 15A through the damping throttle 48A into the spring chamber 17A.

The main valve body 5A is displaced toward the spring chamber 18A due to the pressure difference caused by the throttle 9A, and 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 control ports 41A and 42A are closed, and the spring chamber 17A is closed to the damping throttle 48A and the pilot passage 15.
A communicates with the valve chamber 26A, and the valve chamber 44A communicates with the valve chamber 1.
9A, 21A, spring chamber 18A, pilot passage 16A,
Valve chamber 25A via spring chamber 23A and pilot passage 24A
The pressure difference causes a small displacement of the main valve body 5A, and at the same time, the oil passage sluice valve 10A is pushed toward the valve chamber 25A to open the control port 39A. Pressure oil in the supply boat 2 flows into the internal oil chamber 33A via the valve chambers 36A, 37A, oil passage opening □ 38A, control port 39A, valve chamber 29A, opening 30A, valve chambers 31A, 32A, but the control port 41A Since it is closed, it flows into the spring chamber 22A through the pilot passage 35A of the pressure compensation valve body 8A, and pushes the compensation valve body through the guide 12A against the spring 14A, so that the control □ 39A is closed. When the main valve body 5A is further displaced, the control port 41A is closed and the pressure oil in the internal oil chamber 33A flows out from the valve chamber 44A to the A boat 4A, so the oil pressure in the spring chamber 22A decreases and the compensation valve body The control port 39 is pushed back by the spring 14A.
A opens □, and the pressure oil in the oil passage closing port 38A passes through the control port 39A, the valve chamber 29A, the closing port 30A, the valve chambers 31A, 32A, the internal oil chamber 33A, the control port 41A, and the valve chamber 44A to the A boat 4A.
leaks to.

At this time, the pressure difference between the valve chambers 22A and 23A occupies a position determined by the spring force of the spring 14A and the cross-sectional area of the compensation valve body, thereby controlling the main flow through the control port 39A. Next, when the pilot flow is stopped, the pressure difference across the throttle 9A disappears, and the main valve body 5A returns to the neutral position by the spring force of the springs 6A and 7A, blocking the control port 41A and thus blocking the main flow. do.

Contrary to the above, from A boat 4A to pilot boat 45A
When the pilot flow is allowed to flow in, the pressure oil flows into the boat 45A through the reverse path as described above, and also flows into the spring chamber 17A from the damping throttle 48A to generate a pressure difference in the throttle 9A. The valve body is displaced toward the spring chamber 17A to occupy a position balanced with the spring force of the springs 6A and 6C.

Along with this main valve body displacement, the oil passage switching valve body 10A is pushed toward the valve chamber 26A side due to the pressure difference in the throttle 9A, and the control port 40
A is closed and connected to the discharge boat 3 via the oil passage opening □ 35A and the valve chambers 28A and 27A, but since the control port 42A is closed, the pilot flow also flows into the spring chamber 23A and the compensation is performed. The valve body is pushed through the guide 11A against the spring 13A, thus closing the control port 40A. When the main valve body 5A is further displaced and the control port 42A is closed, the pressure oil in the valve chamber 44A is transferred to the valve chambers 19A, 21A, 20A, the control port 42A, the internal oil chamber 33A, the valve chambers 32A, 31A, and the open □ 30A, 29A, and the pilot passage 34A to the spring chamber 22A and press the compensation valve body to open the control port 40A, so that the pressure oil in the valve chamber 29A flows through the oil passage opening 35A and the valve chamber 28A to the discharge boat. 3. At this time too,
The pressure difference between the spring chambers 22A and 23A is always controlled by the compensating valve body to a value determined by the spring force of the spring 13A and the cross-sectional area of the compensating valve body, thereby performing pressure compensation. As mentioned above, the pilot flow
5A to A boat 4A, the main flow flows from supply boat 2 to A boat 4A, and conversely the pilot flow flows from A boat 4A to A boat 4A.
When flowing from boat 4A to pilot boat 45A,
It flows from the A boat 4A to the discharge boat 3. In addition, since the oil passage switching valve moves and the pilot passage 34A or 16A closes before the main valve body control port 41A or 42A opens, the pressure compensating valve body control port 39A or 40A
is closed, and then the main valve body control port and the compensation valve body control port open □ to allow the main flow of pressure oil to flow, so when the main valve body control port closes, the normal flow rate control valve The jumping phenomenon that occurs in Further, the springs 13A and 14A acting on the compensation valve body are connected to the guides 11A and 12, respectively.
Because A is interposed, the spring forces do not cancel each other out,
Do not go further than when neutral. In this embodiment, since the various parts are configured symmetrically as described above, it is needless to explain in detail that the above-mentioned operation also holds true for the right side. Next, to explain the above-mentioned principle of operation, the cylindrical springs 6A, 7A with a small spring constant and the round springs 6C, 7C with a large spring constant are selected as the displacement control springs of the main valve body 5A. The former spring is pre-stressed and installed so that the main valve body is in the neutral position, and in this neutral position, the latter spring is not applied with spring force to the main valve body 5A, so that the main valve body is free from oil. It is mounted so that it is displaced by pressure and starts acting immediately before the control ports 41A, 42A close.

In this case, by making the spring force of the springs 6C and 7C proportional to the square of the amount of operation, the total spring force will be as shown in FIG. 2. In other words, the displacement of the main valve body is x, the opening degree of the main valve body control port is x, and the overlap amount of the control port (separately stated) is h.
, the circular spring constant is small if kl is the cylindrical spring constant, and k3 is the cylindrical spring constant, so the spring force F acting on the main valve body is F = kl
・(x-h)212・k3・x 2kl. (x-h)2=kl·x2.

The pressure difference △p that occurs before and after the throttle 9A when the flow rate q flows through the pilot circuit is expressed as △p=
R・q2, and the main valve body balance equation is, if the main valve body cross-sectional area is A,
Since A・△p=F=kl・sleeve, the main valve body opening degree x is as follows: x=ノA・R/kl・q.

Further, the pressure difference pm between the control ports 41A and 42A of the main valve body 5A whose pressure is compensated by the pressure compensating valve body 8A is
A, the spring constant of 14A is k2, and the amount of deflection of the spring is Xs
, if the pressure compensation valve body cross-sectional area is Ac, △pm=k
2.Xs/Ac, and is automatically adjusted to a constant value. Therefore, the flow rate Q flowing through the main valve body control ports 41A, 42A is Q=kf. xノ△pm=K●q.

However, K is K=Kf・k2・Xs/Ac・A・R/
kl 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, (
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.

Furthermore, the above explanation holds true regardless of whether the flow is from the supply port to the A or B boat, or from the A or B boat to the discharge boat.

Next, FIG. 3 shows an embodiment of the second invention, in which pobet valves 50A and 51A, which are spring-loaded between the pilot passage 16A, are used in place of the pilot throttle 9A of the embodiment shown in FIG. , except that the cylinders 6'A and 7'A with large simulating constants are arranged, with the flow to be blocked being opposite to each other, and the cylinders 6'A and 7'A with large simulating constants are arranged without installing circular cylinders or springs. It is configured in exactly the same way. The operation of this embodiment is similar to the previous embodiment, except that the povet valve 51
A, 51A controls the main flow by generating a pressure difference according to the pilot flow rate and displacing the main valve body 5A, and when the pilot flow flows from the boat 45A to the A boat 4A, the povet valve 50A is closed. However, in the case of reverse flow, the povet valve 51A is closed.

In these cases, the pressure difference △p before and after each povet valve is determined by △pc being the povet valve cracking pressure, and k being the constant.
If q, then △p=△pc1kq·q, and as shown in FIG. 4, it is almost a straight line.

The pressure difference between the povet valves 50A and 51A and the cylindrical spring 6'
The main valve body 5A stops at a position balanced with the spring forces of A and 7'A, and the control ports 41A and 42A are closed, making it possible to make the main flow rate proportional to the pilot flow rate as in the previous embodiment. .

Next, the functions of the valve device according to the present invention will be further explained with reference to usage examples.The circuit shown in FIG. 1 is an example of a switching valve having a single function.

The pump boat P of the cut-off valve 49 is the pilot boat 4.
6 to supply boat 2, boat A to pilot port 45A, boat B to pilot port 45B,
As described above, the tank boats T are connected to the discharge boats 3 via the pilot boat 47, respectively. Now, when the switching valve is switched to P-A and B-T,
On the A side, the pilot flow is the supply boat 2, the pilot boat 46, the pilot switching valve 49, and the same boat 45A.
, the same passage 15A, the throttle 9A, the same passage 16A, the spring chamber 18A, the valve chambers 21A, 19A, 44A, the A boat 4
On the B side, the main 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 main 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 main flow also flows freely along the aforementioned path. Moreover, the said cut-sliding valve A-T,
When switching to P-B, the main flow flows from the A boat 4A to the discharge boat 3 and from the supply boat 2 to the B boat 4B, as before. In FIG. 5, where the circuit is configured as a switching/flow rate control valve, there is a pipe in the pipeline between the pilot boat 45A and the boat A of the pilot switching valve 49 shown in FIG. The same flow rate control valve 52B is inserted into the B side, and the switching valve is connected to the P-A, B side.
- When switched to T, the pilot flow flows from the supply boat 2 on the A side to the A boat 4A via the path shown, and on the B side also flows from the B boat 4B to the discharge boat 3 via the path shown; Since the flow rate control valve 52A controls and adjusts the pilot flow rate to q, the flow rate of the royal flow is K・q
Therefore, the flow rate from A boat 4A to the actuator is (
10K)q, and since the pilot flow freely flows through the check valve side of the flow rate control valve 52B on the B side, the main flow also flows freely from the B boat 4B to the discharge port 3. Then, when the switching valve is switched to A-T and P-B, A
On the side, the pilot flow flows freely into the discharge boat 3 and B
On the other hand, the flow rate control valve 52B controls the flow rate in the same manner as described above, and the flow rate to the actuator becomes (10K)q. In this case, the pilot flow control valve is originally installed in the meter, so it controls the main flow through the meter, but the control valve is installed in the meter out to control the flow rate of the pilot flow returning to the discharge boat 3. By doing so, it is also possible to control the flow by metering out. Furthermore, to explain the circuit configuration as a functional and pressure reducing valve illustrated in FIG. 6, the pilot boat 4 illustrated in FIG.
A pilot pressure reducing valve 53A is inserted into the conduit between 5A and the switching valve boat A, and the pilot switching valve 49 is connected to P-
When switching to A, B-T, on the A side, if the pressure of the A boat 4A is lower than the pressure reducing valve setting pressure, the pilot flow flows from the supply boat 2 to the A boat 4A via the illustrated path,
The main flow flows from the supply boat 2 to the A boat 4A according to the pilot flow rate, but when the pressure of the A boat approaches the pressure reducing valve setting pressure, the pressure reducing valve flow rate decreases and the main flow rate also decreases, and the A boat 4A The pressure is reduced to the set pressure.

On the B side, the pilot flow flows freely from the B boat 48 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. When the switching valve is switched to A-T and P-B, the pilot flow is a free flow on both sides of A and B, and the king flow is also a free flow.
from the supply boat 2 to the B boat 4B. Furthermore, the circuit configuration as a releaf valve illustrated in FIG. Relief valve 54A, 5
4B, and by switching the switching valve, it operates as a switching valve in the same way as the illustrated example in FIG.
When the pressure in the A-boat 4A becomes higher than the setting of the pilot relief valve 54A, pressure oil flows into the valve chamber 4 as a pilot flow.
The main valve body 5A is displaced by the pressure difference generated at 9A, and the main valve element 5A is displaced by the pressure difference generated at 9A, and the flow is transferred from the A boat 4A to the discharge boat 3. When the pressure is relieved and the pressure decreases, the pilot flow stops and the main valve body 5A is released from the cylindrical spring 6A, the conical spring, and the spring 6.
At C, the boat returns to the neutral position, stops the reef flow to the discharge boat 3, and maintains the pressure of the A boat 4A at the set pressure of the relief valve 46A.

Needless to say, this operation also holds true for the B side. Furthermore, in each of the pipes between the pilot boats 45A and 458 of the pilot circuit and the boats A and B of the pilot switching valve 49 shown in FIG. Control valve 52
In FIG. 8, in which a relief valve 54B and a flow control valve 52B are similarly arranged in the latter pipe line, the A side is fully closed when the pilot switching valve 49 is in the neutral position, but the B side is fully closed. operates, and the pressure oil in the B boat 4B does not rise above the relief valve setting pressure.

Now, when the switching valve 49 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 52A, so that the flow rate is changed from the supply boat 2 to the A boat 4.
A flow rate K.q flows into A, and the pressure reducing valve 53A, which reduces the flow rate flowing out from the A port 4A to less than (10K)q, operates, and the pressure in the -A boat 4A is brought to the pressure reducing valve set pressure. The pressure is reduced, and on the B side, the pilot flow freely flows from the B boat 4B to the discharge boat 3 via the check valve of the flow control valve 52B, so the king flow also freely flows from the B boat 4B to the discharge boat 3. When the switching valve is switched to A-T and PB,
On the A side, the pilot flow flows from the A boat 4A to the pressure reducing valve 53.
Since the main flow flows freely to the discharge boat 3 through the check valves A and flow control valve 52A, 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 controlled by the flow rate control valve to the flow rate q. Since the main flow is regulated and flows to the B boat 4B, the main flow also flows from the supply boat 2 to the B boat 4B, and when the pressure becomes higher than the set pressure of the relief valve 54B, part or all of the pilot flow q is discharged from the relief valve 54B to the discharge boat 3, the flow rate of the main flow also decreases accordingly, and the B boat 4B
The pressure does not exceed the relief valve setting pressure. Moreover, as illustrated in FIGS. 9 and 10, each of the above-mentioned embodiments is
A supply port 2 and a discharge boat 3 pass through the valve body 101.
is provided, the pond valve and the valve body are engaged laterally, and the support plate 1 is installed.
02 are fastened with through bolts 106 and nuts 110, and A boat 4A is attached to the side of the valve body.
A B boat 48 and a bolt hole 107 are provided to connect to the actuator, and a mounting bolt hole 108 and each pilot boat 45A shown in FIG. 11 are provided on the upper surface of the valve body 101.
, 45B. 46, 47 are standardized and the various pilot valves 49, 103, 104, 105, etc. are stacked on top of each other, or alternatively, instead of the aforementioned through-bolt fastening as shown in FIG. By providing the flanges 111 on the side surfaces and performing the valve joint stripes with the short bolts 109 and nuts 11, and performing the above-described configuration, an intervalve circuit configuration may be created in which piping or manifolds are omitted.

As described above, the present invention enables full flow control 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 with the functions required for the main control circuit is constructed by combining small-capacity pilot valves with various single functions, and a small amount of flow in the circuit is used to control the rise of the pilot flow. Since a large-capacity main control valve can be controlled over a wide control range and with a pressure compensation function depending on the direction of flow, the main circuit can be controlled so that a single main control valve can fulfill the same functions as the pilot circuit. Since the main control valve has multiple functions in one unit and can perform functions according to the functions of the pilot circuit, one type of large-capacity control valve can
All you need to do is deploy small pilot valves according to their functions.
Even when systematized as an integrated valve, it can be configured with a small number of types.
In addition, the main control valve can achieve its purpose in combination with the actuator, and the pressure compensation valve is combined with the oil passage switching valve and these are placed in the valve body separately from the main valve body. The oil passages and openings around the body are not complicated, and the main valve body spool has a simple shape, so it is small, lightweight, and inexpensive.

[Brief explanation of the drawing]

Fig. 1 is a configuration explanatory diagram showing a longitudinal cross-sectional view showing an embodiment of the first invention with a pilot switching valve circuit attached, Fig. 2 is a cylinder, a circular sushi, and a spring force and displacement relationship curve diagram of a spring, Fig. 3 4 is a configuration explanatory diagram with a pilot switching valve circuit attached to a longitudinal sectional view showing an embodiment of the second invention, FIG. 4 is a flow rate and pressure characteristic curve diagram of a Pobet valve, and FIGS. FIG. 9 is a configuration explanatory diagram in which a vertical cross-sectional view of an embodiment of the invention is accompanied by different examples of pilot circuits, and FIG. ,
FIG. 10 is a front view of the previous figure, FIG. 11 is a view taken along the line A--A in FIG. 9, and FIG. 12 is a side view showing another example of the valve spacing. 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, 15A, 158... Pilot passage, 9A, 9B... Throttle, 49...
Pilot valve. Figure 1Figure 2Figure 3Figure 4Figure 5Figure 9Figure 10Figure 6Figure 11Figure 7Figure 12Figure 8

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 45.
The hydraulic pressure from A is received on one end side, and the hydraulic pressure from external port 4A is received on the other end side, and the pressure receiving area for the pilot pressure is equal on both end sides, and the pilot pressure is received on one end side, and the other side receives the hydraulic pressure from the external port 4A. A first main control port 41A communicates the external port 4A with the internal oil chamber 33A of the valve body 1 when the valve is displaced to the other side, and a first main control port 41A that communicates the external port 4A with the internal oil chamber 33A of the valve body 1 when the valve body is displaced to the other side. Oil chamber 33
The main valve body 5A has a second main control port 28A that communicates with the main control port 28A symmetrically with respect to the neutral position. The main valve spring, whose spring force change with respect to the main valve body displacement stroke is equal in both directions of the valve body displacement, and the pilot port 45A and the external port 4A are communicated with each other at a predetermined opening degree to create a differential pressure before and after the valve body due to the pilot flow. the resulting pilot orifice, which is slidably arranged within the valve body 1 and supported in a spring-centered manner by pressure compensating valve springs 13A, 14A so as to apply an equal spring force to its displacement from its neutral position; One end receives the hydraulic pressure of the internal oil chamber 33A, and the other end receives the hydraulic pressure of the external port 4A with equal pressure receiving areas, and a concave groove opens to the internal oil chamber 33A on the outer periphery. 29
A pressure compensating valve 8A is formed, and a pressure compensating valve 8A is coaxially arranged on the outer circumference of the pressure compensating valve 8A so that one end receives the hydraulic pressure of the pilot port 45A and the other end receives the hydraulic pressure of the external port 4A. A pair of pressure compensation control ports 39A and 40A that are slidably fitted and communicated with the internal oil chamber 33A together with both shoulders of the concave groove 29A on the outer periphery of the pressure compensation valve are formed. When the pressure compensation control port 39A is connected to the pressure oil supply port 2 and the other 40A is closed, the hydraulic pressure of the external port 4A is received at the other end and the valve is displaced to the other side. A pair of switching oil passage openings 38A are arranged symmetrically with a concave groove 29A on the outer periphery of the pressure compensating valve body in between, so that when this happens, the other pressure compensation control port 40A is connected to the discharge port 3 and one 39A is closed. and an oil passage switching valve 10A provided with an oil passage switching valve 35A; further, the pilot orifice is a fixed orifice 9A, and the main valve spring is actuated by cylindrical springs 6A and 7A that act from when the pilot flow is small, and when the pilot flow is large to a certain extent. A hydraulic control valve device characterized in that it is combined with conical springs 6C and 7C which act after bending and increase the spring force as they bend. 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. The pilot port 45 is configured to control the flow of the main circuit by a pilot operation method by displacing the main valve against the main valve spring.
The hydraulic pressure from A is received on one end side, and the hydraulic pressure from external port 4A is received on the other end side, and the pressure receiving area for the pilot pressure is equal on both end sides, and the pilot pressure is received on one end side, and the other side receives the hydraulic pressure from the external port 4A. A first main control port 41A communicates the external port 4A with the internal oil chamber 33A of the valve body 1 when the valve is displaced to the other side, and a first main control port 41A that communicates the external port 4A with the internal oil chamber 33A of the valve body 1 when the valve body is displaced to the other side. Oil chamber 33
The main valve body 5A has a second main control port 42A that communicates with the main control port 42A, which is formed symmetrically with respect to the neutral position. The main valve spring, which has the same spring force change with respect to the main valve body displacement stroke in both directions of the main valve body displacement, and the pilot port 45A and the external port 4A are communicated with each other at a predetermined opening degree, and a differential pressure is created before and after the main valve spring by the pilot flow. a pilot orifice that generates a pressure, and a pilot orifice that is slidably disposed within the valve body 1 and supported in a spring center manner by pressure compensating valve springs 13A and 14A so that an equal spring force acts on displacement from the neutral position. , one end side receives the hydraulic pressure of the internal oil chamber 33A, the other end side receives the hydraulic pressure of the external port 4A with equal pressure receiving areas, and a recess opened to the internal oil chamber 33A on the outer periphery. Groove 2
9A is formed, the hydraulic pressure of the pilot 45A is connected to one end, and the external port 4A is connected to the other end.
A concave groove 29 on the outer periphery of the pressure compensating valve is slidably fitted coaxially to the outer periphery of the pressure compensating valve 8A so as to receive the hydraulic pressure of the pressure compensating valve 8A.
Together with both shoulders of A, a pair of pressure compensation control ports 39A and 40A are formed which communicate with the internal oil chamber 33A. The pressure compensation control port 39A is connected to the pressure oil supply port 2 and the other 40A is closed, and when the other end receives the hydraulic pressure of the external port 4A and is displaced to the other end, the other pressure compensation control port 40A is connected to the discharge port. an oil passage switching valve 10A, which is provided with a pair of switching oil passage openings 38A, 35A symmetrically with a concave groove 29A on the outer periphery of the pressure compensating valve body in between, so as to connect to the oil passage opening 38A and close one 39A; further comprising a poppet valve 50 which opens the pilot orifice when the pilot pressure on the upstream side thereof exceeds a certain pressure and thereafter generates a differential pressure according to the pilot flow rate.
A, 51A, and the main valve spring is a cylindrical spring 6'A 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. , 7'A.