JP2729885B2 - Gate valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gate valve having a valve body which moves in a direction perpendicular to a flow direction in a valve box,
The valve element has a support member that moves up and down, and the support member supports a deformable seal member for sealing a valve box opening and a valve box inner peripheral wall. About.

[0002]

2. Description of the Related Art As shown in FIG. 4, a conventional gate valve uses ordinary piping as a valve box 01. In this case, a valve box opening 02 is provided in the piping as the valve box 01. A lid 04 for closing the valve box opening 02 and rotatably supporting the screw spindle 03 is connected to the pipe 01 via a flange connection portion 05 and a split joint 06. A valve body 07 is supported in the pipe 04 and the pipe 01 so as to be vertically movable by a screw spindle 03. In this case, the valve body 07 is
And a rubber annular first seal member 09 for sealing the valve box opening 02.
And a rubber-made U-shaped second seal member 011 that can be deformed in the radial direction to seal the inner peripheral wall 010 of the valve case.

[0003] The operation of the gate valve having such a configuration will be described particularly with respect to the valve closing process. When the screw spindle 03 is rotated in the valve closing direction, the support member 08 screwed to the screw spindle 03 becomes the first and second seal members 09 and 01.
1 and gradually descends until the second seal member 01
The curved lower end surface of the valve body 1 comes into contact with the bottom of the inner peripheral wall 010 of the valve case. After that, when the screw spindle 03 is further rotated to forcibly depress the support member 08, the second seal member 011 is compressed in the vertical direction. The bulge is forcibly bulged in the direction and comes into contact with the inner peripheral wall 010 of the valve case. By further rotating the screw spindle 03, the sealing surfaces of the second sealing member 011, that is, the lower end surface and the left and right side surfaces are pressed against the inner peripheral wall 010 with sufficient force, and at the same time, the first sealing member When 09 is pressed against the periphery of the valve box opening 02 in the same manner, the closing of the gate valve is completed.

[0004]

In the gate valve having such a structure, both legs are indirectly bulged in the radial direction based on the vertical compression of the second seal member 011. In order to obtain sufficient sealing pressure, the second
Had to be compressed quite vertically in the vertical direction. Therefore, due to such strong compression, not only the second seal member 011 but also the pipe 01 as the valve box, the screw spindle 03, and the support member 0
8, and an excessive load is inevitably generated on the lid 04 and the like, and therefore, there is a disadvantage that the service life of each member becomes extremely short.

In closing the valve, the screw spindle 03
In order to receive the excessive compression resistance of the second seal member 011, the torque required to rotate the screw spindle 03 sharply increases. This causes a decrease in the operability of the gate valve.

The present invention has been made in consideration of such a problem, and the right and left sides of the seal member are directly swelled in the radial direction to minimize the overall compression amount of the seal member. It is an object of the present invention to sufficiently extend the service life of the gate valve and improve the operability of the gate valve.

[0007]

In order to achieve the above object, in the gate valve of the present invention, the support member includes a pair of widening members and includes an auxiliary member, and the auxiliary member includes a support member. While moving the member up and down, when closing the valve, a pressing force is applied to the widening member to forcibly move the widening member in the lateral direction, whereby both sides of the seal member face the inner peripheral wall of the valve box. It is characterized by being swollen.

[0008]

When the auxiliary member is lowered in order to close the gate valve, the valve body is lowered by its own weight following the downward movement of the auxiliary member. Eventually, when the lower end surface of the seal member comes into contact with the bottom of the inner peripheral wall of the valve box and the downward movement of the valve body stops,
Thereafter, only the auxiliary member is lowered. In this case, since the auxiliary member is forcibly pressed down with the lowering of the widening member, a part of the widening member is pushed out against the elastic force of the seal member. Therefore, the seal member is gradually pushed down and simultaneously swells toward both sides of the inner peripheral wall of the valve box. Thus, when the sealing surface of the seal member is pressed against the inner peripheral wall of the valve box with a sufficient force, at the same time, the upper portion of the seal member is also pressed with a sufficient force against the peripheral portion of the valve box opening (not shown). It will be crimped.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1, 2 and 3 show an embodiment of a valve body 1 according to the present invention. The valve body 1 includes a support member 2, an auxiliary member 3 located in the support member 2, and a support member 2.
A cover 5 for closing the opening 4 and a rubber seal member 6 fitted around the support member 2. The support member 2 includes two housing grooves 8 for housing the widening member 7 and a cylindrical portion 9 that partially supports the seal member 6.
And a flange 10 coupled to the cover 5.

The two receiving grooves 8 are each provided with two side plates 1.
It is constituted by one and one web 12 and is directed diametrically outward from one another and extends over substantially the entire height of the support member 2. Each side plate 11 extends from the lower end of the support member 2 to the flange 10, while the web 12
Without being reached halfway through. Each side plate 11 is connected to the cylindrical portion 9 at the upper portion, and the upper ends of the cylindrical portion 9 and the side plate 11 are connected to the flange 10. Also, the two housing grooves 8 are connected to each other at the lower ends thereof by an arc-shaped bottom 13 corresponding to the shape of the inner peripheral wall of the valve box (not shown).

The widening member 7 accommodated in the two accommodation grooves 8
Is a rigid cylindrical body 7 made of plastic or metal in this embodiment. Further, the housing groove 8 is filled with a lubricant as needed.

The rubber sealing member 6 has a bag-like shape and completely surrounds the supporting member 2 except for the flange 10. The sealing member 6 has a cylindrical upper part 14 corresponding to the shape of the valve box opening for sealing a valve box opening (not shown) when the valve is closed, and from this upper part 14 through a conical transition part 15. , A flat lower portion 16 having substantially the same width as the valve box opening
Has been migrated to. The lower portion 16 of the seal member 6 is for sealing between the valve housing inner peripheral wall (not shown) and the valve element 1 when the valve is closed.

The sealing member 6 has an inner surface shape which most conforms to the shape of the support member 2. Therefore, for example, inwardly protruding ridges 17 are provided on both side portions of the seal member 6, and the ridges 17 protrude into the accommodating grooves 8, so that the individual widening members 7 are constantly moved based on the elastic action. Pressing. However, a space for the auxiliary member 3 is left in the central region of the seal member 6. In addition, several bolts 18 are implanted in the upper part of the seal member 6, and these bolts 18 pass through the flange 10 and the cover 5 in a state where the valve body 1 is assembled as shown in FIG. I have. A nut 19 is fastened to a portion where the bolt 18 penetrates, whereby the seal member 6 is connected to the support member 2 and the cover 5.

In the space left in the central region between the support member 2 and the seal member 6, an auxiliary member 3 is disposed so as to be vertically movable. The auxiliary member 3 includes a tubular screw portion 21 that is screwed to a screw spindle 20 rotatably supported by a lid (not shown), and enters the accommodation groove 8 of the support member 2 from above and is inserted into the widening member 7. It comprises two hook-shaped pressing portions 22 that come into contact with each other in a pressable manner. The screw portion 21 of the auxiliary member 3 is guided in a vertical direction, that is, in a vertical direction by a cylindrical guide surface 23 provided on the cover 5.

The cover 5 is provided with at least one radial projection (not shown). The projection is provided in a vertically extending groove provided on the inner peripheral wall of the lid or flange connecting portion (not shown). Has rushed into.
With such a configuration, the valve element 1 or the support member 2
Can be moved up and down without rotating around the screw spindle 20.

Next, the operation of this embodiment will be described.

First, in the valve-open state, the auxiliary member 3 is located sufficiently above the screw spindle 20. Therefore, the upper end of the pressing portion 22 of the auxiliary member 3 is shown on the left side of FIG. Thus, by engaging with the cover 5, the cover 5, that is, the valve element 1 is pulled up from a valve box (not shown). At this time, the pressing portion 22 of the auxiliary member 3 hardly exerts a pressing force on the widening member 7 in the accommodation groove 8 of the support member 2, and therefore, the individual widening member 7
Are arranged neatly and linearly in the accommodation groove 8 in order to receive only a horizontal inward elastic pressing force from the rubber seal member 6.

Next, when the screw spindle 20 is rotated to lower the auxiliary member 3 in order to close the gate valve from this state, the valve body 1 is also lowered by its own weight following the downward movement of the auxiliary member 3. I do. Eventually, the lower part 1 of the sealing member 6
When the lower end surface of the valve body 6 comes into contact with the bottom of the inner peripheral wall of the valve box (not shown) and the descending movement of the valve body 1 stops, thereafter, only the auxiliary member 3 descends according to the rotation of the screw spindle 20. In this case, each pressing portion 22 of the auxiliary member 3 descends along each accommodation groove 8 of the support member 2, and accordingly, the forcibly pushing down the widening member 7 in the accommodation groove 8 is performed. The linear arrangement of the inner widening members 7 is broken, and several widening members 7 are pushed outward against the elastic force of the seal member 6.

Therefore, the flat lower part 1 of the seal member 6
6 is gradually pushed down, and at the same time, swells laterally, that is, toward both sides of the inner peripheral wall of the valve box (not shown) (right side in FIG. 2). Thus, the lower part 16 of the seal member 6
Is pressed against the inner peripheral wall of the valve box (not shown) with a sufficient force,
Is pressed against the periphery of the valve box opening (not shown) with a sufficient force.

Next, in order to open the gate valve from this closed state, the screw spindle 20 may be rotated in the opposite direction. In this case, the movement of each member of the valve body 1 is completely opposite to the movement at the time of closing the valve. That is, the widening member 7 that has been pushed outward in the housing groove 8 is gradually pushed inward by the elastic force of the seal member 6 as the auxiliary member 3 rises. Are separated from both sides of the inner peripheral wall of the valve box (not shown). At this time, the support member 2 also slightly rises in accordance with the expansion of the lower end of the lower portion 16 pressed against the bottom of the inner peripheral wall of the valve box.

When all the widening members 7 are linearly arranged again in the accommodation groove 8, the upper end of the pressing portion 22 of the auxiliary member 3 is engaged with the cover 5. Thereafter, following the movement of the auxiliary member 3, the support member 2, that is, the valve body 1 is similarly raised.

In the above embodiment, if a part of the pressing portion 22 of the auxiliary member 3 is configured to directly engage with the upper end portion of the web 12 constituting the accommodation groove 8 when the valve is closed,
The compression of the seal member 6 in the vertical direction is performed more reliably.

[0024]

According to the present invention, when the valve is closed, the right and left sides of the seal member can be directly bulged in the radial direction by the auxiliary member and the widening member. No need to overcompress. Therefore, since an excessive load can no longer act on each member, the service life of the gate valve can be greatly extended. Further, even when the valve is closed, for example, the rotational torque of the screw spindle is kept relatively small based on such proper compression action of the seal member, so that the operability of the gate valve is improved.

[0025]

[Brief description of the drawings]

FIG. 1 is a side view including a partial vertical cross section of a valve body according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the valve body at a position different from that of FIG. 1 by 90 °, wherein the left side shows a valve open state and the right side shows a valve closed state.

FIG. 3 is a cross-sectional view taken along line BB of FIG. 2;

FIG. 4 is a longitudinal sectional view of a conventional gate valve, in which the left side shows a valve open state and the right side shows a valve closed state.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Valve body 2 Supporting member 3 Auxiliary member 4 Opening 5 Cover 6 Sealing member 7 Widening member 8 Housing groove 9 Cylindrical part 10 Flange 11 Side plate 12 Web 13 Bottom part 14 Upper part 15 Transition part 16 Lower part 17 Protrusion 18 Bolt 19 Nut 20 Screw spindle 21 screw portion 22 pressing portion 23 guide surface

Claims (6)

(57) [Claims] 1. A gate valve having a valve element that moves in a direction perpendicular to the flow direction in a valve box, wherein the valve element has a support member that moves up and down. Is a type in which a deformable seal member for sealing the valve box opening and the valve box inner peripheral wall is supported, wherein the support member includes a pair of widening members and includes an auxiliary member, The auxiliary member moves the support member up and down, and when closing the valve, exerts a pressing force on the widening member to forcibly move the widening member in the lateral direction,
Thereby, a gate valve characterized in that both sides of the seal member are bulged toward the inner peripheral wall of the valve box. 2. The gate valve according to claim 1, wherein the support member is formed with two vertically extending accommodation grooves for accommodating the widening member. 3. The widening member is a plurality of cylinders, and is linearly arranged in the accommodation groove.
3. The gate valve according to claim 2, wherein the gate member is always elastically pressed by the seal member. 4. The gate valve according to claim 2, wherein a protrusion that protrudes into the housing groove and presses the widening member is provided on an inner surface of the seal member. 5. The gate valve according to claim 2, wherein the housing groove is filled with a lubricant. 6. A cover is provided at an upper end of the support member, and the support member is lifted upward by engaging the auxiliary member with the cover. The gate valve according to any one of the above.