JPH09166229A - Rotary type four-way switching valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate generation of a gall and seizure even by sliding friction, thermal expansion, or the like and prevent a leak of fluid, in a sliding surface between a valve case internal surface and a valve unit. SOLUTION: A valve unit 15 supported to a valve rod 16 is stored in a valve case 10 comprising a valve main unit 11 having connection ports 11a to 11d in four directions and both side covers 13, 14. Valve vanes 18, comprising a peripheral surface part 18a into slide contact with an inner circumferential surface of the valve main unit 11 and a side surface part 18b into slide contact with an internal surface of both the side covers 13, 14, are mounted in the valve unit 15, and these peripheral/side surface parts 18a, 18b are energized so as to protrude outward by coil springs 19a, 19b built in the inside, so that a surface pressure is generated in a contact surface between an internal surface of the valve case 10 and a sliding surface of the valve vane 18. The valve vane 18 is constituted by a heat/wear resistant material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention allows a valve body to rotate 90 ° forward and backward in a valve box having connection ports in four directions.
The present invention relates to a rotary type four-way switching valve capable of switching a flow path in four directions, and more particularly to a valve body seal portion for eliminating fluid leakage.

[0002]

2. Description of the Related Art Conventionally, for example, when the supply of fuel gas and the exhaust of combustion exhaust gas of an industrial furnace are switched, four two-way valves are installed and the switching operation of each valve is performed by switching solenoid valves. It is also known that the operation is performed by a rotary type four-way switching valve. When switching the fluid, especially high-temperature gas, with the rotary four-way valve, the inner peripheral surface of the valve box and the sliding surface of the valve element are actuated due to thermal expansion, mist or drain in the exhaust gas, or clogging. Accidents such as impossible are likely to occur. Therefore, it is common to have a structure in which a direct contact between the sliding surfaces is avoided and a gap is provided in advance. However, in this case, there has been a problem that fluid leakage from this gap constantly occurs, and a decrease in combustion efficiency cannot be avoided.

FIG. 4 shows an example of the prior art. In the valve body 1 having the connection ports 1a to 1d on all sides, the connection ports 1a to 1d of the valve body 1 at predetermined two positions.
A rotary valve body 2 for communicating adjacent ones with each other is supported by a rotary shaft 3 which is rotated from the outside, and a valve body 1 of the rotary valve body 2 is provided.
A clearance setting member 4 that slides and wears against the inner peripheral surface 1e of the valve body is provided at a portion that slides in contact with the valve body, and a constant gap is provided by the sliding contact between the clearance setting member 4 of the rotary valve body 2 and the valve body 1. A rotary four-way valve for a heat storage type radiant tube burner that has formed No.
8276 gazette).

Further, as shown in FIGS. 5 (a) and 5 (b), the valve shaft 3 is erected so as to be rotatable at the center of the main body 1 in which openings 1a to 1d are formed in a cross shape in four directions. Valve seat projections 6, 6 are provided so as to cross the inside of the main body 1 obliquely while intersecting with the bearing portion of the valve shaft 3, and the valve seat projections 6, 6 are provided on the valve shaft 3 every 90 ° rotation. There has already been devised a switching valve in which an elliptical butterfly (valve body) 7 for contacting the outside is fixedly attached, and the butterfly 7 is fully rotatable with respect to the main body 1. (Actual Kosho 3
In the drawing, 8 is a hard rubber lining layer, 9 is a handle for manual opening and closing, and 9a is a pointer.

[0005]

As described above, FIG.
In the prior art shown in FIG. 1, a wear setting clearance setting member 4 is provided at a sliding portion of the valve body 2 that slides on the inner peripheral surface 1e of the valve box 1, and a constant gap 5 is formed by sliding the valve body 2. In this way, the leak amount is made constant regardless of the rotational position of the valve body 2.

Further, in the prior art shown in FIG. 5, a valve seat projection 6 is formed so as to cross the valve body 1 obliquely, and a valve shaft projection 9 is formed on the valve shaft 3.
An elliptical valve body 7 that is brought into contact with the outside of the valve seat protrusion 6 is fixed every time it is rotated by 0 °, and the fluid flow is switched by rotating this.

As described above, in the conventional example shown in FIG. 4, a constant gap is provided on the sliding surface between the valve body peripheral surface and the valve body (valve box) inner surface, and as shown in FIG. In this case, a hard rubber lining layer 8 is provided on the inner surface of the valve body 1 so as to prevent leakage as a valve seat, and therefore, the maximum operating temperature is limited to about 100 ° C. As described above, there is a problem in that it cannot be used for combustion gas at about 300 ° C.

According to the present invention, the sliding surface between the inner surface of the valve body consisting of the valve body and the lids on both sides and the valve body does not cause galling or seizure due to sliding friction or thermal expansion, and prevents fluid leakage. It is an object to provide a rotary type four-way switching valve which is prevented.

[0009]

In order to solve the above-mentioned problems, the invention according to claim 1 supports a valve body in a valve body having connection ports in four directions so as to be rotatable forward and backward by 90 °. In a rotary four-way switching valve that is provided so that the flow path can be switched in four directions, a seal member is attached to the sliding surface of the valve blade of the valve body that faces the inner peripheral surface of the valve body and the inner surfaces of both lids, The seal member is biased outward by an elastic member built in the seal member, and a surface pressure is applied to the contact surfaces of the inner surfaces of the valve body and both lids and the valve blade sliding surface of the valve body. It is characterized by being configured to generate.

The invention according to claim 2 is characterized in that the seal member is made of a heat-resistant and abrasion-resistant material such as carbon, carbon-containing Teflon, glass-containing Teflon or carbon fiber. The invention of 3 is characterized in that the elastic member for urging the sealing member to project outward is constituted by an elastic spring such as a leaf spring or a coil spring.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to an embodiment shown in the drawings. FIG. 1 is a sectional view of a rotary type four-way switching valve of the present invention. FIG. 1 (a) is a sectional view in a direction perpendicular to a valve rod, and FIG. 1 (b) is I- in FIG. 1 (a).
It is sectional drawing containing the valve stem by I line.

In the figure, a valve box 10 includes a valve main body 11 having connection ports 11a to 11d in four directions, and a double-sided lid fastened to both side surfaces of the valve main body 11 by bolts and nuts (shown by a center line) 12. A valve body 15 is fixedly attached to a valve rod 16 driven from the outside by a connecting pin 17 inside the valve box 10.

As shown in FIG. 1 (a), the valve body 15 is provided on the outside with the inner peripheral surface of the valve body 11 and the lids 13 and 14 on both sides.
The valve blades 18, which are in sliding contact with the inner surface of the, respectively, are attached so as to be integrally rotatable. The valve blade 18 is made of a heat-resistant and wear-resistant seal material made of carbon, Teflon containing carbon, Teflon containing glass, carbon fiber, etc., and as shown in FIGS. The inner peripheral surface 18a of the valve vane 18 is slidably in contact with the inner peripheral surfaces of the side lids 13 and 14, and the side surface 18b is slidably in contact with the inner surfaces of the both side lids 13 and 14. A coil spring 19a for urging the peripheral surface portion 18a so as to project outward in the radial direction and a coil spring 19b for urging the side surface portions 18b respectively outwardly in the axial direction are arranged in mutually orthogonal directions and with each other. It is built in by shifting the position so that it does not interfere. In addition, these peripheral surface portions 1
The contact surfaces 18c between the both end portions of 8a and the inner side surfaces of the both side surface portions 18b are the contact surfaces of the respective surface portions when the both surface portions 18a and 18b are simultaneously urged to project outward. Since the 18c tend to separate from each other, the fluid may leak from the high pressure side to the low pressure side from the separated contact surface 18c. In order to prevent this, as an example, a plurality of radial grooves are formed inside the side surface 18b of the contact surface 18c, while the inside of the groove is formed at both ends on the side of the peripheral surface 18a. By integrally forming the protrusions that are slidably fitted with each other while maintaining a narrow gap, fluids having different pressures acting on both sides in the rotation direction of the peripheral surface portion 18a of the valve vane 18 during the operation of the rotary valve are different in pressure side. Even if an attempt is made to leak from the low pressure side (back side) through the gap generated in the contact surface portion,
Since the protrusion and the groove which are slidably fitted to each other while maintaining the narrow gap are formed in the portion 8c, the fitting portion of the fitting portion having a large fluid resistance, which is orthogonal to the direction in which the fluid pressure acts, is formed. The amount of fluid that leaks from the high pressure side to the low pressure side through the slit is limited.

FIG. 3 shows another embodiment (example) of the present invention.
2B is a diagram similar to FIG. 2B, and the same reference numerals as those shown in FIG. 2B indicate the same or similar parts. In this embodiment, on the outside of the valve body 15, a peripheral surface portion 18a that rotates integrally with the valve body and is in sliding contact with the inner peripheral surface of the valve body 11, and both side surface portions that are in sliding contact with the inner surfaces of the both side lids 13 and 14. The fact that the valve vane 18 composed of 18b and 18b is urged by the elastic member built in so as to project outward is the same as in the above-described embodiment (FIG. 2), but the peripheral surface portion 18a The difference is that the elastic member built inside the both side surface portions 18b is formed by the leaf springs 29a and 29b.

Next, the operation will be described. As shown in FIG. 1 (a), when the valve body 15 is used by mounting it through a valve rod 16 in a valve box 10 having connection ports in four directions, it is shown by a solid line in FIG. 1 (a). At the rotational position of the valve body 15 that has been opened, the connection ports 11b and 11c and 11a and 11d are connected.
Are communicated with each other, the fluid flows along the communicated flow paths, and at the position indicated by the alternate long and two short dashes line by rotating the valve body 15 by 90 °, the fluid is connected to the respective communicating ports 11a. Flowing along the flow path passing through 11b and 11c and 11d is no different from the conventional one, but when the working fluid has a high temperature like the fuel gas of an industrial furnace, the valve box 10
Although the inner surface of the valve body and the sliding surface of the valve body 15 tend to cause galling due to thermal expansion, the valve body 15 of the present invention is urged by an elastic spring so as to project outward, and the valve body 11
18a that is in sliding contact with the inner peripheral surface of the
Of the side surface portion 18b that is in sliding contact with the inner surface of the
Since it is mounted so as to rotate integrally with the valve body, even if the contact force at the sliding contact surface portion between the inner surface of the valve box and the valve body side is increased by the thermal expansion, the valve blade 18 becomes elastic spring force. Since it can be displaced inward by the amount of thermal expansion, the above-mentioned galling and seizure do not occur, and the sliding contact surface is subjected to surface pressure due to the force of the elastic spring, so there is no gap. Does not occur, and there is no fluid leakage.

Further, since the seal member constituted by the above-mentioned valve vane 18 is made of carbon, Teflon containing carbon, Teflon containing glass, carbon fiber, etc., it is excellent not only in heat resistance but also in abrasion resistance. The contact surface pressure between the peripheral surface of the valve body and the inner surface of the valve box can be properly maintained to prevent leakage of fluid such as gas or air, enabling smooth rotation of the valve body over a long period of time. ing.

In addition to the materials of the seal member exemplified above, ceramic materials and the like are available as materials having heat resistance and wear resistance.

As the elastic member for urging the sealing member to project outward, in addition to the coil spring and the leaf spring, a C-shaped curl spring obtained by deforming the thin plate into a C-shaped cross section, or a thin plate is spirally wound. It is also possible to house the spiral spring formed by rolling in a circular shape in the inside of the seal member, and use the repulsive force of these springs to urge the seal member to project outward.

[0019]

As described above, according to the present invention,
According to the invention of claim 1, the valve body is provided in a valve body having connection ports in four directions so as to be rotatable forward and backward by 90 degrees,
In a rotary type four-way switching valve capable of switching a flow path in four directions, a seal member is attached to a sliding surface of a valve blade of a valve body that faces an inner peripheral surface of a valve body and inner surfaces of both lids. Is urged outward by an elastic member built inside thereof to generate surface pressure on the contact surfaces of the inner surfaces of the valve body and both side lids and the valve blade sliding surface of the valve body. With this configuration, it is possible to eliminate the gap that is conventionally provided to prevent galling on the sliding surface between the inner surface of the valve box and the peripheral surface of the valve body due to thermal expansion or the like, so that fluid leakage is prevented. Further, the elastic repulsive force of the elastic member incorporated inside the seal member can prevent galling and seizure due to thermal expansion of the valve box and the valve body.

In the invention of claim 2, the seal member is made of a heat-resistant and wear-resistant material such as carbon, Teflon containing carbon, Teflon containing glass, or carbon fiber. Even in the case of high-temperature fluid such as gas, it prevents galling and seizure due to thermal expansion etc. on the sliding surface between the valve box and the valve body, and enables smooth valve body rotation for a long period of time. It is possible to improve efficiency and operating efficiency of the device.

Further, in the invention of claim 3, an elastic member for urging the seal member to project outward is provided.
By using elastic springs such as leaf springs or coil springs, it has a simple structure and has little influence on the elastic action due to heat. It enables the rotation of the valve body.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a rotary four-way switching valve showing an embodiment of the present invention, in which FIG. 1 (a) is a cross-sectional view in a direction perpendicular to a valve rod, and FIG. 1 (b) is I in FIG. 1 (a). It is a -I line sectional view.

FIG. 2A is a front view showing an embodiment of a valve body, and FIG.
The left half of FIG. 3 is a cross-sectional view taken along the line II-II of FIG. 7A, and the right half of FIG. 7B is a top view of the right half of FIG.

FIG. 3 is a view similar to FIG. 2 (b) showing another embodiment of the valve body.

FIG. 4 is a schematic view of a four-way valve showing a conventional example.

FIG. 5 is an explanatory view of a four-way valve showing another conventional example, and FIG. 5 (b) is a sectional view taken along line bb of FIG. 5 (a).

[Explanation of symbols]

 10 valve box 11 valve body 13,14 both side lid 15 valve body 16 valve rod 17 connecting pin 18 valve blade 18a peripheral surface portion 18b side surface portion 19a, 19b coil spring 29a, 29b leaf spring

Claims (3)

[Claims] 1. A rotary type four-way switching valve in which a valve body is provided in a valve body having connection ports in four directions so as to be rotatable forward and backward by 90 °, and a flow path can be switched in four directions. A sealing member is attached to the sliding surface of the valve blade of the valve body facing the inner peripheral surface of the valve body and the inner surfaces of both side lids, and the sealing member is attached to the outside by an elastic member built in the sealing member. A rotary four-way switching valve, characterized in that it is configured to generate surface pressure on the contact surfaces of the inner surfaces of the valve body and both side lids and the valve blade sliding surface of the valve body. 2. A heat-resistant and wear-resistant material made of carbon, Teflon containing carbon, Teflon containing glass, or carbon fiber is used as a seal member attached to the sliding surface of the valve blade of the valve body. A rotary type four-way switching valve according to item 1. 3. A rotary member according to claim 1, wherein the seal member attached to the sliding surface of the valve blade of the valve body is biased so as to project outward from the inside by an elastic spring. Type 4-way switching valve.