JPH09303589A - Shut-off valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the shut-off valve suitable to a multiple string type laminated valve for construction machines, which communicates the loading pressure of a right and a left running motor with, or isolates the aforesaid pressure from pressure at the upstream side of a direction control valve and the like, thereby enhance running straight ahead properties, and furthermore make the valve small in size, and inexpensive. SOLUTION: A main body part is provided with a valve body 20 which is provided for the inner oil chamber 19 of the main body part 15 in such a way as to be freely moved, opening holes 17 which are communicated with each other within the inner oil chamber so as to be opened at both sides of the chamber, and with valve seats 18 which can be blocked by letting the valve body abut against the main body, each handle part 12 is inserted into the respective opening holes from the outward side of the main body part in such a way that it can abut against the valve body while each gap is being provided in the radial direction, the respective handle parts are so designed as to be energized to the valve body side by springs 9, and pilot ports 8 are thereby provided, which are communicated with the gaps 21 in the radial direction of the outer circumferences of the handle parts respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shutoff valve for a straight traveling control circuit for controlling straight traveling in a hydraulic circuit that supplies pressure oil to left and right traveling motors of a hydraulic traveling vehicle.

[0002]

2. Description of the Related Art A conventional straight ahead control circuit is disclosed in, for example, Japanese Utility Model Laid-Open No. 3-50589. As shown in the hydraulic circuit diagram of FIG. 4, the left and right traveling motors 31 and 32 for driving the left and right crawlers of a construction machine or the like are provided with variable displacement pumps 35 and tank circuits 36 via direction switching valves 33 and 34, respectively. , 37, pressure compensation valves 38, 39 are provided between the directional control valve and the variable displacement pump, respectively, and the higher load pressure 40 of the travel motors 31, 32 is selected by the shuttle valve 41. In a so-called load sensing circuit leading to the tilt angle control valve 42 of the variable displacement pump 35, the connection paths 43 and 44, which are downstream of the pressure compensation valves 38 and 39 and serve as pump ports of the directional control valves 33 and 34, are piloted. The pilot passages are connected by passages 45 and 46, and when the pressure difference between the pilot passages 45 and 46 exceeds the set pressure of the springs 57a and 57b, the pilot passages are connected to the pilot passages. Shut-off valve 51 is provided Jill.

According to this structure, the directional control valves 33, 3 are provided.
4 can be switched by the same stroke, pressure compensating valve 3
Although the differential pressures before and after the directional control valves 33 and 34 are controlled to be equal by 8 and 39, the same flow rate is supplied to the respective traveling motors. Spring force of pressure compensating valve 38a, 3
If there is an error of 9a, the flow rate supplied to one of the traveling hydraulic motors increases, and this causes a cause of impeding the straight traveling of the hydraulic traveling vehicle. At this time, the load pressure of the traveling motor on the side where the supply flow rate has increased becomes temporarily high, so that there is a difference in the pressures of the connection paths 43 and 44 connecting the directional control valves and the pressure compensating valves. Pressure oil flows from the connection passage on the side with the higher load pressure to the connection passage on the side with the lower load pressure via the connecting pilot passages 45, 46, and as a result, the side with the higher load pressure, that is, the supply flow rate increases. The number of rotations of the traveling motor on the raised side does not increase, and it is possible to automatically prevent the straight traveling from bending.

When the hydraulically traveling vehicle is turned to the left or right, the stroke of one of the directional control valves 33 and 34 is shortened so as to reduce the passing flow rate. The pressure in the connecting passages 43, 44 connecting the directional control valve and the pressure compensating valve in front thereof is connected by the pressure in the connecting passages 43, 4 connecting the other directional control valve and the pressure compensating valve in front thereof.
When there is a difference more than the set value than the pressure of 4, the shut-off valve 5 provided between the pilot passages 45 and 46 connecting both connection passages
1 operates so as to close the pilot passage, and the small flow rate of the flow passing through the one directional control valve is maintained, so that the vehicle can turn as it is.

By the way, as shown in the cross-sectional view of FIG. 5, the shut-off valve 51 used in this one has a central portion so as to traverse a pilot passage 53 provided at the center in a substantially rectangular parallelepiped valve body 52. Is provided with a spool 55 having a notch portion 54, and spring receivers 56a, 56 are provided on both sides of the spool 55.
Springs 57a and 57b are arranged via b. Spring chambers 58a, 58 in which springs are inserted
In b, the communication passages 5 communicating with the pilot passages 53, respectively.
The pilot pressure is guided by 9a and 59b.

In the shutoff valve 51, if the pilot ports 60a and 60b have the same pressure, the spool 5
5. Since pressure oil does not flow through the central cutout 54 and no differential pressure is generated, the pressures introduced from the respective pilot ports to the spring chambers 58a and 58b are the same, and the spool is kept at the central position. On the other hand, as described above, when a difference occurs in the load pressure of the traveling motors 31, 32, the pressure oil in the connection path between the direction switching valves 33, 34 and the pressure compensating valves 38, 39 flows from one pilot port 60a, 60b to the other. It flows into the pilot ports 60b and 60a. Therefore, since a pressure difference is generated in the notch 54 at the center of the spool, the spring chambers 58a, 58 pass through the communication passages 59a, 59b.
A pressure difference also occurs in the pressure guided to b. Therefore, the spool 55 is biased toward the lower pressure in the spring chambers 58a and 58b due to the force relationship between the pressure difference and the spring force.
When the pressure difference is small, the spool 55 remains open and the connection path 4 between the direction switching valves 33 and 34 and the pressure compensation valves 38 and 39 is connected.
3, 44 are made to communicate with each other. When the pressure difference becomes larger, the spring force is overcome and the spool 55 is further moved to close the pilot ports 60a and 60b.

In this way, the above-described running linearity and operability at the time of changing the direction are improved. Such a shut-off valve is used in various circuits as described in JP-A-6-48197, in addition to the above-mentioned. Although the shutoff valve is provided in the pilot passage from the connection passage of the directional control valve and the pressure compensating valve in the above-mentioned Japanese Utility Model Laid-Open No. 3-50589, in Japanese Unexamined Patent Publication No. 6-48197.
It is provided between the pilot passages on the load side. In Japanese Utility Model Laid-Open No. 6-14503, a throttle is provided between the pilot passages on the load side.

[0008]

However, the shut-off valve 51 having the structure shown in FIG.
A space for accommodating 7b is required. in addition,
The communicating passages 59a and 59b are formed in a slanted hole in the main body and guided to the spring chambers 58a and 58b, so that the processing is complicated. In particular, there is a problem that the space is too large, the entire valve becomes large, and in order to make it compact, it is not suitable for a valve for construction machinery in which multiple block bodies are stacked and tightened with connecting bolts. It was Further, there is a problem that a large cost is required due to complicated diagonal hole processing.

The object of the present invention has been made in view of the above-mentioned problems, and it is more compact, and moreover, it has a structure which is widely adopted in control valves for construction machines of this type, that is, a plurality of block main bodies are used. An object of the present invention is to provide a shut-off valve that is suitable for a structure in which layers are stacked and tightened with connecting bolts to form multiple lines. Further, the present invention provides an inexpensive shutoff valve without performing complicated processing.

[0010]

In order to achieve the above-mentioned object, the shut-off valve of the present invention communicates with a valve body movably provided in an internal oil chamber of the main body, and is open at both ends in the internal oil chamber. An opening hole and a valve seat provided at an edge portion of each opening hole that can be closed by abutting the valve body are provided in the main body portion. The handle portion is inserted from the outside of the main body portion so as to be able to contact the valve body with a radial gap in each opening hole. Furthermore, the problem has been solved by providing a pilot port that communicates with each of the radial gaps by urging each handle portion toward the valve body with a spring.

The valve body is preferably a sphere.

It is preferable that the main body has a substantially hollow cylindrical shape and is divided into two parts at the substantially central part so that the opening holes at both ends face each other.

The handle portion is provided with a hollow cylindrical portion having a diameter smaller than the outer diameter of the main body portion and capable of contacting the end surface of the main body portion, and a communication passage for communicating the radial gap with the inside of the hollow cylindrical portion is provided. A spring is inserted inside the provided hollow cylindrical portion.

From each of the mating surfaces of the two blocks, a fitting insertion hole into which the main body divided into two parts is fitted and a sliding hole in which the hollow cylindrical portion of the handle is slidable in an oil-tight manner, The pilot port opened on the bottom of the sliding hole is provided in sequence. A hollow cylindrical portion having a diameter smaller than the outer diameter of the main body portion and capable of contacting the end surface of the main body portion, a handle portion having a communication passage that communicates the radial gap and the inside of the hollow cylindrical portion, and a substantially hollow cylindrical shape. The main body part divided into two parts at the substantially central part so that the opening holes at both ends face each other are sequentially assembled into the sliding hole and the fitting insertion hole, respectively, and the internal oil formed in the divided surface of the main body part The valve body is installed in the chamber and the block is assembled.

(Operation) When there is a pressure difference between both pilot passages, the pilot pressure oil on the high pressure side flows from the high pressure side pilot port into the oil chamber inside the main body through the radial gap on the outer circumference of the handle portion. It passes through the periphery of the valve body, reaches the other opening hole, and flows to the pilot port on the low pressure side from the radial gap on the outer circumference of the other stem portion. When the flow rate is low, the valve body hardly moves and the opening hole is open. The valve body tries to sit on the valve seat at the edge of the opening hole on the downstream side due to the increase in the flow rate, but the seat is blocked by the handle portion biased by the spring. Furthermore, when the flow rate increases, a pressure loss occurs between the valve body and the valve seat of the opening hole on the downstream side, and a closing force acts in the direction in which the valve body is seated on the valve seat on the downstream side. When the pressure loss overcomes the set value of the spring force, the valve body sits on the valve seat and closes the downstream opening hole. When the pressure difference between the pilot pressures becomes equal to or less than the set value of the spring force, the valve body separates from the valve seat and the opening hole is opened.

When the valve body is a sphere, it is easy to sit on the valve seat and is small in size.

If the main body is divided into two parts from the center, parts can be shared.

The handle portion for urging the valve element is centered by the hollow cylindrical portion, and the hollow cylindrical portion is brought into contact with the end surface of the main body portion to regulate the axial position. Further, since the spring is inserted inside the hollow cylindrical portion, and the communication passage is provided between the inside of the hollow cylindrical portion and the radial gap on the outer periphery of the handle portion, the overall size is reduced, and the pressure oil has a pilot port and a spring. The oil flows into or out of the main body internal oil chamber through the inside of the hollow cylindrical portion of the inserted handle, the communication passage, and the radial gap of the outer circumference of the handle.

A body portion, a handle portion, a spring, and a pilot port are formed on each of the mating surfaces of the two blocks,
Since the valve element is installed in the internal oil chamber formed by the main body, a structure that is often used in control valves for construction machines, that is, a plurality of block main bodies are stacked,
Suitable for a structure in which multiple bolts are tightened with connecting bolts.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a shutoff valve that is an embodiment of the present invention. In FIG. 1, the respective valve block bodies 2a and 2b are laminated on a mating surface 3 and are joined together by connecting bolts or the like (not shown) to form the entire valve. The shutoff valve 1 is
The structure is almost symmetrical except for the sealing member 4 on the mating surface. That is, each valve block body 2a, 2b is provided with a stepped body hole having insertion holes 5a, 5b opened perpendicularly to the mating surface 3 and sliding holes 6a, 6b in the back. . Pilot ports 8a, 8b in which pressure oil can flow in and out of the central portions of the bottom surfaces 7a, 7b of the sliding holes 6a, 6b
Is provided. Springs 9a and 9b are inserted so that one ends of the bottom surfaces 7a and 7b of the body hole are in contact with each other.
The end faces of the springs 9a and 9b are connected to the inside 10a of the hollow cylindrical portion,
The end faces 11a and 11b of 10b are inserted in contact with the end faces 11a and 11b, and the tapered shank portions 12a and 12b on the side opposite to the spring and the hollow cylindrical portion 13 are inserted.
The poppets 14a and 14b composed of a and 13b are sliding holes 6
It is slidably inserted in a and 6b.

The body portions 15a, 15b, which are substantially hollow cylindrical and have a substantially concave axial cross-section, abut on the end faces 16a, 16b of the different diameter portions of the fitting insertion holes 5a, 5b and the sliding holes 6a, 6b. The concave side is fitted into the fitting hole with the opening side facing the mating surface 3. The end surfaces of the main body portions 15a and 15b on the block mating surface 3 side are substantially flush with each other within a range that does not project from the mating surfaces of the blocks 2a and 2b. Opening holes 17a and 17b are provided at substantially the center of the main body recess, and valve seats 18a and 18b are formed at the edges of the opening holes. The main body part inserted into both blocks is configured such that the recesses face each other to form a main body part internal oil chamber 19, and a spherical valve body 20 is installed in the main body part internal oil chamber.

Handles 12a, 1 of poppets 14a, 14b
2b is made to project into the opening holes 17a, 17b of the main body, the tip of which is brought into contact with the valve body 20, and radial gaps 21a, 21b are formed between the outer circumference of the handle and the opening hole. A diameter difference is provided between the outer diameter of the handle and the inner diameter of the opening so that the oil passage has an appropriate size. Also,
From the hollow cylindrical portion inside 10a, 10b into which the springs 9a, 9b are inserted, toward the outer periphery of the handle portions 12a, 12b, that is, the radial gaps 21a, 21b, the communication passages 22a, 22 are provided.
b is provided. Tapered portions 23a and 23b that spread outward from the opening holes 17a and 17b are provided on the end surfaces of the body portions 15a and 15b on the poppet 14a and 14b side, and the edge of the end surface of the poppet side of the opening hole is the handle portion 12a.
The root of 12b does not interfere, and the oil passage is secured.

O-rings 24a for preventing leakage between pilot ports are provided on the outer circumferences of the main bodies 15a, 15b.
24b is provided, but even if there is no O-ring, the leak amount between the pilot ports is very small with respect to the flow rate supplied to the traveling motor.
24b may be omitted. In addition, O- around the outer periphery of the main body 15b
The ring 4 is for preventing external leakage from the mating surface of the block, but this O-ring is another O-ring provided for preventing external leakage from other ports in the same block. It need not be provided as long as it can be prevented.

The pilot ports 8a and 8b may be communicated with the hollow cylindrical portion interiors 10a and 10b, respectively, at positions where they do not interfere with the sliding of the poppets 14a and 14b. Moreover, in this embodiment, the poppets 14a and 14b are used.
In order to form the communication passages 22a and 22b of the hollow cylindrical portions 10a and 10b, they are formed by passing through drilled holes toward the radial gaps 21a and 21b on the outer circumferences of the stalks 12a and 12b. Anything is acceptable as long as it allows communication between the insides 10a, 10b of the hollow cylindrical portions and the radial gaps 21a, 21b. For example, slits are formed in the outer peripheral sliding portions of the hollow cylindrical portions 13a, 13b of the poppets 14a, 14b in the axial direction. It may be processed. Further, the lengths of the handle portions 12a and 12b are such that a predetermined spring force is exerted when the tip end of the handle portion abuts on the valve body before the valve body 20 is seated and the valve body is seated on the valve seats 18a and 18b. To be

Next, the operation of the first embodiment of the present invention will be described. FIG. 2 is a hydraulic circuit diagram in which a cross-sectional view of the shutoff valve of the present invention is schematically arranged in the circuit diagram, and some of the reference numerals in FIG. 1 are omitted. Note that FIG.
4 uses the shutoff valve of the present invention in the hydraulic circuit of FIG. 4, and is the same in terms of circuit. In FIG. 2, both pilot ports 8a and 8b are connected to the connecting path 4 of the direction switching valves 33 and 34 of the left and right traveling motors 31 and 32 and the pressure compensating valves 38 and 39.
3, 44 are connected to the pilot passages 45, 46, respectively. When there is a pressure difference between the two pilot passages 45 and 46, for example, when the left pilot pressure is high in FIG. 2, the pilot pressure oil on the high pressure side is inserted into the spring 9 a from the high pressure side pilot passage 45. Block 2
a sliding hole 6a of a, the inside 10 of the hollow cylindrical portion of the poppet 14a
A, the communication passage 22a, the taper portion 23a, and the radial gap 21a on the outer circumference of the handle portion flow into the main unit internal oil chamber 19.
Further, the pressure oil passes through the periphery of the valve body 20 and reaches the other opening hole, and the radial gap on the outer circumference of the other handle portion, the taper portion, the communication passage, the inside of the poppet hollow cylindrical portion, the block sliding hole, and the low pressure. It flows from the side pilot port 8b to the pilot passage 46.

By the way, when the equal flow rates are supplied to the left and right traveling motors while the vehicle is traveling straight, it is assumed that the pressures in the connecting passages 43 and 44 are substantially equal, and therefore there is a pressure difference between the pilot passages 45 and 46. Since the valve body 20 is very small, the valve body 20 hardly moves. Further, even if it moves, it does not come into contact with the tip of one of the handle portions 12a, 12b to sit on the valve seat, so both opening holes are opened and the pilot ports 8a, 8b are in communication. In this case, since the pressures of both connecting paths 43 and 44 are originally almost equal to each other, the straightness can be ensured while the flow rates flowing into the left and right traveling motors 31 and 32 remain the same.

While traveling straight ahead, as described above, the flow rate supplied to one of the traveling motors is large due to an error in machining the spools of the directional control valves 33 and 34 and an error in the spring forces 38a and 39a of the pressure compensation valve. Then, the load pressure of the traveling motor on the side where the supply flow rate increases becomes temporarily high, and the pressures of the connecting paths 43 and 44 connecting the directional control valves and the pressure compensating valves also differ from each other, so that they are connected to each other. Pilot passage 45,46
The pressure oil flows from the connection passage on the side of the high load pressure to the connection passage on the side of the low load pressure via the valve body 20, and the valve body 20 tries to sit on the valve seat at the edge of the opening hole on the downstream side. However, the spring 9
The spring forces of a and 9b are set so as to be larger than the closing force of the valve body which is to be seated due to the pressure loss generated between the valve body and the valve seat of the opening hole on the downstream side in a normal straight traveling state. Therefore, the valve body 20 is prevented from being seated by the handle portion urged by the downstream spring. Therefore, the opening hole is still opened, and the pressure oil flows from the connection path on the higher load pressure side to the connection path on the lower load side, and as a result, the side with the higher load pressure, that is, the side with the higher supply flow rate. The number of revolutions of the traveling motor does not increase, and the curve of the straight traveling can be automatically prevented and the traveling straightness can be secured.

On the other hand, when the vehicle travels in a curved state (direction change), the stroke of one of the direction change valves 33, 34 is reduced to reduce the control flow rate of the direction change valve. Then, the pressures in the connecting passages 43 and 44 of the directional control valves of both the left and right traveling motors and the pressure compensating valve are such that the traveling motors on the outer side with respect to the center of the bending radius on the side where the flow rate is larger than the traveling motors on the inner side. It will be extremely large. Therefore, as seen in the figure, when the stroke of the right-side directional control valve 34 is reduced, the right-side traction motor 32 decelerates to the inner side and the left-side traction motor 31 becomes the outer side. The pressure in the connection passage 43 of No. 2 is extremely higher than the pressure in the connection passage 44 for the right directional control valve and the pressure compensation valve. Therefore, the valve body 20 of the shutoff valve 1 abuts the handle portion 12b against the spring force of the right spring 9b due to the pressure difference, slides the poppet 14b backward, and seats on the valve seat 18b. The communication between 8a and 8b is cut off. Therefore, the pressure in each of the connection paths 43 and 44 becomes a pressure commensurate with the load pressure of each traveling motor. Therefore, the flow rate of the traveling motor 31 on the left side (outer side) is set to the traveling motor 32 on the right side (inner side).
Flow into the respective traveling motors without any flow into the vehicle, and desired traveling in a curved direction is possible.

The outer circumference of the hollow cylindrical portion 13 of the poppet 14 is
It is slidably inserted into a sliding hole 6 concentric with the fitting insertion hole 5 of the body portion 15, and the tip of the handle portion 12 is also at the center of the opening hole 17,
That is, since it is concentric with the center of the valve seat 18, the center position of the handle is constant, and the valve body 20 is seated stably at the center of the valve seat.

A pilot port 8, a sliding hole 6 and a fitting insertion hole 5 are formed in the mating surface 3 of the two blocks from the back, and a spring 9, a poppet 14 and a main body 15 divided into two parts from the center are formed in each. However, since the valve element 20 is internally housed in the internal oil chamber 19 formed by the main body, the parts can be shared, and the axial length is shorter than that of the conventional example. Further, since the opening hole is opened in the axial direction, the outer diameter is small.

A second embodiment of the present invention will be described. FIG. 3 is a hydraulic circuit diagram in which a cross-sectional view of the shutoff valve of the present invention is schematically arranged in the circuit diagram. In the second embodiment, the pilot passages 45 and 46 of the first embodiment are connected to the connection passages 43 and 44 of the direction switching valves 33 and 34 of the left and right traveling motors 31 and 32 and the pressure compensation valves 38 and 39, respectively. However, as shown in FIG. 3, the two pilot passages are different in that the load pressures 63 and 64 of the left and right traveling motors are connected to the pilot passages 65 and 66, respectively. Others are the same as those in the first embodiment, so the same reference numerals are given,
Description is omitted. In addition, this is the actual Kaihei 6-
This is an example of the case where the throttle valve between the pilot passages on the load side of Japanese Patent No. 14503 is replaced with a shutoff valve.

[0032]

As described above, according to the present invention, an opening hole opened at both ends which is opened and closed by the contact of the valve body, and a handle which is urged by a spring and protrudes into the opening hole so that its tip end contacts the valve body. Parts are arranged, and pilot passages are provided on both sides, and the flow of pressure oil is in the axial direction, so it is more compact, and moreover, it is a structure that is often adopted in control valves for construction machines of this kind, It became possible to provide a shut-off valve suitable for a structure in which the block main bodies are laminated and tightened with connecting bolts to form a multiple series.

Further, the valve body is a sphere, the main body part is divided into two parts in the substantially central part, the hollow cylindrical part is provided in the handle part, and the radial gap on the outer circumference of the handle part communicates with the inside of the hollow cylindrical part. Since the communication passage is provided and the spring is inserted inside the hollow cylindrical portion, it becomes possible to provide an inexpensive shut-off valve without making smaller and complicated processing.

Further, a pilot port, a sliding hole, and a fitting insertion hole are provided from the back on each of the mating surfaces of the two blocks, and a spring, a hollow cylinder portion and a handle portion having a communicating passage and a main body portion are provided in these holes. The blocks are assembled in sequence, the valve element is installed inside the dividing surface of the main body, and the block is easily assembled.Furthermore, it does not require a complicated shape with a small number of parts, and it is space-saving and compact. It also has an excellent feature that it can be constructed at low cost.

Furthermore, the structure in which the valve body blocks, which are often used in the control valves for continuous machines, are laminated and fastened with connecting bolts or the like does not require or reduce the increase in thickness or outward dimension. Therefore, there is no need to prepare a special main body or to install a mounting part to configure the shut-off valve, the entire valve can be made compact, and no parts that have undergone special and complicated processing are required. It is possible to obtain an excellent effect that a conventional shutoff valve can be configured and which is not available in the prior art.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a shutoff valve of the present invention.

FIG. 2 is a hydraulic circuit diagram showing the first embodiment of the present invention.

FIG. 3 is a hydraulic circuit diagram showing a second embodiment of the present invention.

FIG. 4 is a hydraulic circuit diagram of the traveling motor according to the present invention.

FIG. 5 is a cross-sectional view of a conventional shutoff valve.

[Explanation of symbols]

 1 Shut-off valve 2 Valve block 3 Mating surface 5 Fitting hole 6 Sliding hole 7 Sliding hole bottom 8 Pilot port 9 Spring 10 Hollow cylindrical part inside 11 End face 12 Handle part 13 Hollow cylindrical part 15 Main body part 17 Opening hole 18 Valve seat 19 body internal oil chamber 20 valve body 21 radial gap 22 communication passage

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area F16K 11/044 F16K 11/044 Z

Claims (5)

[Claims] 1. A valve element movably provided in an internal oil chamber, opening holes communicating with the internal oil chamber and opening at both ends, and the respective opening holes that can be closed by abutting the valve element. A main body portion having a valve seat provided at the edge portion of the main body portion, and a stem portion inserted into each of the opening holes with a radial gap from the outside of the main body portion so as to be able to contact the valve body, respectively. A shut-off valve having a spring for urging the handle portion toward the valve body and a pilot port communicating with the radial gap. 2. The shutoff valve according to claim 1, wherein the valve body is a sphere. 3. The shutoff valve according to claim 1, wherein the main body has a substantially hollow cylindrical shape, and the main body is divided into two parts at a substantially central part so that the opening holes at both ends face each other. 4. The handle portion has a hollow cylindrical portion having a diameter smaller than the outer diameter of the main body portion and capable of contacting an end surface of the main body portion, and an inside of the hollow cylindrical portion having the spring inserted therein. And a communication passage communicating with the radial gap and the inside of the hollow cylindrical portion.
Alternatively, the shutoff valve described in 3. 5. A fitting insertion hole into which the main body part divided into two parts according to claim 3 is fitted and inserted into each of the mating surfaces of the two blocks, and the hollow of the handle part according to claim 4. The cylindrical portion has a sliding hole capable of sliding in an oil-tight manner, and the pilot port opened on the bottom surface of the sliding hole, and the handle portion has a diameter smaller than the outer diameter of the body portion and the body. A hollow cylindrical portion that can be brought into contact with the end surface of the portion, a communication passage that communicates with the radial gap and the inside of the hollow cylindrical portion, and the inside of the hollow cylindrical portion into which the spring is inserted. The main body portion is substantially hollow and cylindrical, and is divided into two substantially in the central portion so that the opening holes at both ends face each other.
The handle portion and the main body portion are sequentially assembled in the sliding hole and the fitting insertion hole, respectively, and the valve body is installed in an internal oil chamber formed in a divided surface of the main body portion. The shutoff valve according to claim 1, wherein the shutoff valve is provided.