JPH0953730A - Manufacture of double seat valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a double seat valve capable of making a first plug integral with a second plug. SOLUTION: In a double seat valve 6 having a pair of first and second valve seats 61, 62 provided on a shaft and a pair of first and second plugs 63, 64 opened and closed simultaneously with the first and second valve seats 61, 62, after the first and second plugs 63, 64 are formed integral with the second valve seat 62, the second valve seat 62 is separated from the first and second plugs 63, 64 and then the first valve seat 61 is fixedly connected to the second valve seat 62.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a double seat valve in which a pair of first and second valve seats provided on one shaft are opened and closed by a pair of first and second plugs moving on the shaft. Regarding In the double-seat valve, the seal diameters of the first and second plugs are formed to be the same or substantially the same, so that the opening / closing valve force due to the fluid pressure is canceled and the pair of plugs can be operated with a small driving force. It is a thing.

[0002]

2. Description of the Related Art FIG. 4 shows a conventional double seat valve. This double-seat valve includes a first valve seat 101, a second valve seat 102,
First plug 103, second plug 104, seal pipe 10
5 and a set screw 106. First, the first plug 103 is inserted into the first valve seat 101, and the first valve seat 10
The first and second valve seats 102 are connected and fixed by screws (not shown). Next, the seal pipe 105 is inserted into the lower shaft portion 107 of the first plug 103, and the second plug 104 is attached to the first plug 10.
3 is screwed and fixed by a set screw 106. The first valve seat 101 and the second valve seat 102 provided on one axis are opened and closed by the first plug 103 and the second plug 104 moving on this axis. Reference numeral 108 is an annular seal surface provided on the first valve seat 101, and 109 is the second valve seat 102.
It is an annular seal surface provided on the. The seal diameters of the seal surface 108 and the seal surface 109 are the same. Reference numeral 110 denotes an upper shaft portion provided on the first plug 103, and a driving member is connected to the upper shaft portion 110.

[0003]

In the above-mentioned conventional method, since the second valve seat is located between the first plug and the second plug, the first plug and the second plug are formed separately. Was there. Therefore, when connecting and fixing the first plug and the second plug, it is difficult to align the two plugs and adjust the parallelism, and this causes a valve leakage. Furthermore, the first plug and the second
There has been a problem that a member for sealing between the plugs and a locking member are required, resulting in high cost.

In view of the above-mentioned conventional problems, the present invention has a technical problem of making the first plug and the second plug integrally.

[0005]

Technical features of the present invention:
In a double seat valve having a pair of first and second valve seats provided on one shaft and a pair of first and second plugs that move on the shaft to simultaneously open and close the first and second valve seats. , The first and second plugs and the second valve seat are integrally formed, the second valve seat is separated from the first and second plugs, and then the first valve seat and the second valve seat
It is a method of manufacturing a double-seat valve in which valve seats are connected and fixed.

[0006]

According to the present invention, the first and second plugs and the second valve seat are integrally formed, and then the second valve seat is separated from the first and second plugs. The second valve seat can be positioned between the two even if they are integrally formed. Therefore, the connecting work and the adjusting work of the first plug and the second plug are unnecessary, and the seal member and the locking member are also unnecessary.

[0007]

EXAMPLE A specific example in which the double-seat valve of the present invention is applied to a liquid pumping device for pumping a liquid such as water or fuel will be described below. FIG. 1 is a sectional view of a liquid pumping device having a double seat valve according to a specific embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of the double-seat valve of the liquid pumping device of FIG. FIG. 3 is a cross-sectional view of the double-seat valve of FIG. 2 in which the first and second plugs and the second valve seat are integrally formed. In FIG. 1, the liquid pressure-feeding device 1 of the present embodiment has a closed container 2 in which a float 3, a switching valve 4, a snap mechanism 5, and a double-seat valve 6 are arranged.

Explaining in sequence, the closed container 2 has a main body portion 7
And the lid portion 8 are connected by screws (not shown), and a liquid storage space 10 is formed therein. In the present embodiment, the main body 7 of the closed container 2 is a mere container, and the characteristic components of the present embodiment are generally provided on the lid 8 of the closed container 2. That is, the lid 8 is provided with four openings, specifically, a working fluid inlet 11, a working fluid outlet 13, a pumping liquid inlet 16, and a pumping liquid outlet 17.

An air supply valve 20 is attached inside the working fluid inlet 11, in other words, a position inside the closed container 2, and an exhaust valve 21 is attached inside the working fluid outlet 13. Here, the air supply valve 20 is constituted by a valve case 22, a valve body 23, and a lifting rod 24. The valve case 22 has a through hole in the axial direction, and the upper end surface of the through hole functions as a valve seat 25. In the middle part of the valve case 22, there are provided four openings 26 for communicating the aforementioned through holes with the outside. The valve element 23 has a hemispherical shape, and is integrally attached to the tip of the lifting rod 24.

In the liquid pumping apparatus 1 of this embodiment, the air supply valve 2
The tip of the 0 valve case 22 is screwed into the working fluid inlet 11. And the valve body 23 is the working fluid inlet 1
On one side, the lifting rod 24 passes through the through hole of the valve case 22 to the closed container 2 side, and comes into contact with the continuous plate 27. The connecting plate 27 is connected to the valve shaft operating rod 28. Further, the valve shaft operating rod 28 is connected to the snap mechanism 5.

The exhaust valve 21 is composed of a valve case 29, a valve body 30, and a lifting rod 31. The valve case 29 has a through hole in the axial direction. A valve seat 32 is provided inside the through hole, and a valve body 30 held and fixed to the tip of an elevating rod 31 from below the valve seat 32 is brought into contact therewith. It opens and closes. The valve shaft operating rod 28 and the lifting rod 31 are connected by a pin 33. The switching valve 4 is constituted by the air supply valve 20 and the exhaust valve 21. The exhaust valve 21 is closed when the air supply valve 20 is opened, and the exhaust valve 21 is opened when the air supply valve 20 is closed.

The pressure-feeding liquid inlet 16 is located substantially in the center of the lid portion 8, and the pressure-feeding liquid outlet 17 is provided at a position corresponding to the lower portion of the closed container 2.

The float 3 is supported by a bracket 36 via a lever 34 and a shaft 35, and the snap mechanism 5 is supported by a bracket 38 via a first shaft 37. The bracket 36 and the bracket 38 are joined by screws (not shown) and integrally attached to the lid portion 8 of the closed container 2. The lever 34 is made by bending a plate into a "U" shape, and two plates are opposed to each other in parallel. The float 3 is connected to the bent portion of the lever 34. A shaft 40 is attached to the other end of the lever 34.

When viewed from above, the bracket 36 is composed of two "L" -shaped plates, and the shafts 41 and 42 and the shaft 35 are connected to each other. The shaft 35 also serves as the swing shaft of the float 3. Float 3 has shaft 35
It swings up and down around. The shafts 41 and 42 also serve as upper and lower limit stoppers for the float 3. On the other hand, similarly, the bracket 38 is also made up of two "L" -shaped plates, and the shaft 43 and the above-mentioned first shaft 37 are bridged and connected. Axis 43 is the following sub arm 5
Also serves as a stopper for 2.

The snap mechanism 5 includes a floating arm 51,
The sub arm 52 includes a coil spring 54 in a compressed state, a spring receiving member 55, and a spring receiving member 56. The front arm 51 is composed of two plates facing each other in parallel,
A groove 57 is provided at the left end of the two plates. The right end of the float arm 51 is rotatably supported by the first shaft 37 described above. Also the front arm 51
The shaft 40 of the lever 34 described above is fitted in the groove 57. Therefore, the float arm 51 follows the ups and downs of the float 3 and swings up and down about the first shaft 37.

The right end of the float arm 51 expands downward, and the second shaft 58 parallel to the above-mentioned first shaft 37 is stretched over the lower end thereof, and the spring receiving member 55 is arranged at the first end. It is rotatably supported by two shafts 58. The upper end of the sub arm 52 is rotatably supported by the first shaft 37. The sub arm 52 is composed of two plates facing each other in parallel, and each plate has an inverted "L" shape. At the lower end of the sub arm 52, the first and second shafts 3 described above are provided.
A third shaft 59, which is parallel to 7, 58, is bridged, and the spring bearing member 56 is rotatably supported by the third shaft 59. The compressed coil spring 54 is attached between the spring receiving members 55 and 56. Further, a shaft 60 is wound around the upper left end of the sub arm 52, and the valve shaft operating rod 28
The lower ends of are connected. A window 81 is opened in the front arm 51 so as not to hinder the movement of the shaft 60.

A double-seat valve 6 is provided on the liquid reservoir space 10 side of the pressure-feeding liquid discharge port 17. The double seat valve 6 includes a first valve seat 61, a second valve seat 62, a first plug 63 and a second plug 6.
It consists of 4. Upper shaft portion 65 and lower shaft portion 66
The first plug 63, the second plug 64, and the second valve seat 62 having the above are integrally formed by precision casting as shown in FIG. 3, and then the portion of reference numeral 69 indicated by cross-hatching is cut off, 2 valve seat 62 to the first plug 6
3 and the second plug 64. As a result, the second valve seat 62 can be positioned between the first plug 63 and the second plug 64. After that, the first valve seat 61 and the second valve seat 6
2 are connected and fixed by screws (not shown). First valve seat 6
The 1st and 2nd valve seats 62 are provided on one axis, and are opened and closed by the 1st plug 63 and the 2nd plug 64 which move on this axis. Reference numeral 67 is an annular seal surface provided on the first valve seat 61, and 68 is an annular seal surface provided on the second valve seat 62. The seal diameters of the seal surface 67 and the seal surface 68 are the same. Then, the first valve seat 61 is fixed to the lid portion 8 with a screw (not shown).

An upper end of the upper shaft portion 65 is swingably connected to a drain valve shaft 71 by a shaft 70, and an upper end of the drain valve shaft 71 is swingably connected to a float arm 51 by a shaft 72. ing. The first and second plugs 63 and 64 are
As the float 3 rises, it moves downwards and the liquid storage space 1
0 and the pressure-feeding liquid discharge port 17 communicate with each other, move upward as the float 3 descends, and shut off the liquid reservoir space 10 and the pressure-feeding liquid discharge port 17 as shown in FIG. .

Next, the operation of the liquid pressure-feeding device 1 of the present embodiment will be described by following a series of operation procedures when steam is used as the working fluid. First, the working fluid introduction port 11 is connected to a high-pressure steam source, and the working fluid discharge port 13 is connected to a steam circulation pipe. In addition, the pumping liquid inflow port 16 is connected to the liquid storage space 1
It is connected to a load such as a steam-using device via a check valve (not shown) that opens toward zero. On the other hand, the pumping liquid discharge port 17
Is connected to a liquid pressure destination such as a boiler via a check valve (not shown) which opens outward from the liquid storage space 10.

The liquid reservoir space 1 of the liquid pumping device 1 of this embodiment
If there is no condensate within 0, the float 3 is located at the bottom as shown in FIG. At this time, the air supply valve 20 of the switching valve 4 is closed, and the exhaust valve 21 is open. In addition, the double seat valve 6 is closed. Then, when condensed water is generated in a load such as a steam-using device, the condensed water flows down from the pumping liquid inlet 16 to the liquid pumping device 1 and accumulates in the liquid storage space 10.

When the float 3 floats up due to the condensed water stored in the liquid storage space 10, the lever 34 rotates in the clockwise direction around the shaft 35, and the shaft 72 which is a connecting portion with the drain valve shaft 71. Moves downward, the first and second plugs 63 and 64 move downward via the drain valve shaft 71, and the double-seat valve 6 opens.

On the other hand, on the side of the snap mechanism 5, the float arm 51 rotates counterclockwise about the first shaft 37 in conjunction with the downward movement of the shaft 40 due to the rotation of the lever 34. The second shaft 58, which is the connecting portion with the coil spring 54, moves to the right to approach the line connecting the first shaft 37 and the third shaft 59, and the coil spring 54 is compressed and deformed. And flow
3 further rises, and the second shaft 58 and the third shaft 37
When the second shaft 58 moves to the right of the line connecting the first shaft 37 and the third shaft 59, the coil spring 54 becomes The deformation suddenly recovers, the sub arm 52 rotates clockwise, and the third arm
Axis 59 snaps to the left. As a result,
The valve shaft operating rod 28 connected to the shaft 60 of the valve 52 moves upward, the air supply valve 20 is opened, and the exhaust valve 21 is closed.

When the working fluid introducing port 11 is opened, high-pressure steam is introduced into the closed container 2 and the internal pressure rises,
The condensed water collected in the liquid storage space 10 is pushed by the vapor pressure and discharged from the pumping liquid discharge port 17 to an external boiler or waste heat utilization device via a check valve (not shown).

As a result of discharging the condensate, the water level in the condensate storage space 10 lowers and the float 3 descends. Then Lever 3
4 rotates in the counterclockwise direction around the shaft 35, the shaft 72 that is a connecting portion with the drain valve shaft 71 moves upward, and the first and second plugs 63 and 64 are connected via the drain valve shaft 71. Moving upward, the double seat valve 6 closes.

On the other hand, on the side of the snap mechanism 5, the float arm 51 rotates clockwise around the first shaft 37 in conjunction with the upward movement of the shaft 40 due to the rotation of the lever 34, The second shaft 58, which is a connecting portion with the coil spring 54, moves to the left to approach the line connecting the first shaft 37 and the third shaft 59, and the coil spring 54 is compressed and deformed. Then, the float 3 is further lowered, the second shaft 58 is aligned on the line connecting the first shaft 37 and the third shaft 59, and the float 3 is still lowered and the second shaft 58 is moved to the first shaft 58. When it moves to the left of the line connecting the first shaft 37 and the third shaft 59, the coil spring 54 suddenly recovers from the deformation, and the sub arm 52 rotates counterclockwise to move the third shaft.
Axis 59 snaps to the right. As a result,
The valve shaft operating rod 28 connected to the shaft 60 of the valve 52 moves downward, the air supply valve 20 closes, and the exhaust valve 21 opens.

[0026]

In the double seat valve of the present invention, since the first and second plugs are integrated, the parallelism is improved, the dimensional accuracy of the seal position is improved, valve leakage does not occur, and alignment and positioning are performed. There is an excellent effect that adjustment work becomes unnecessary.

[Brief description of drawings]

FIG. 1 is a sectional view of a liquid pumping device having a double-seat valve according to a specific embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a double-seat valve of the liquid pumping device of FIG.

FIG. 3 is a cross-sectional view showing a state where the first and second plugs and the second valve seat of the double-seat valve of FIG. 2 are integrally formed.

FIG. 4 is a cross-sectional view of a conventional double seat valve.

[Explanation of symbols]

 2 Airtight container 3 Float 4 Switching valve 5 Snap mechanism 6 Double seat valve 11 Working fluid inlet 13 Working fluid outlet 16 Pressure liquid inlet 17 Pressure liquid outlet 61 First valve seat 62 Second valve seat 63 1st Plug 64 Second plug 65 Upper valve shaft 66 Lower valve shaft

Claims (1)

[Claims] 1. A pair of first and second uniaxially provided
In a double seat valve having a valve seat and a pair of first and second plugs that move on the shaft to open and close the first and second valve seats at the same time, the first and second plugs and the second valve seat are provided. A method for manufacturing a double-seat valve, characterized in that after being integrally formed, the second valve seat is separated from the first and second plugs, and then the first valve seat and the second valve seat are connected and fixed.