JPH0630560U - Bellows for valve device - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a bellows for a valve device, which has excellent corrosion resistance and is not easily damaged. [Structure] The whole is formed into a tubular shape from a material having excellent corrosion resistance such as PTFE. A plurality of inner concave grooves 21 and 21 and outer concave grooves 22 and 22 are provided in the intermediate portion. The inner concave grooves 21, 21 are formed at equal pitches and open on the inner peripheral surface of the intermediate portion. The outer concave grooves 22, 22 are formed at a pitch equal to the above pitch and open to the outer peripheral surface of the intermediate portion. However, the outer concave grooves 22 and 22 are formed in a state of being displaced from the inner concave grooves 21 and 21 in the axial direction by ½ of the pitch. The bottoms of the inner concave grooves 21 and 21 are V-shaped in cross section, and the bottoms of the outer concave grooves 22 and 22 are arcuate in cross section.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is incorporated in, for example, a three-way valve that constitutes a culture device, and prevents the culture fluid flowing in the three-way valve from leaking from the portion where the rod penetrates the end wall of the casing that constitutes the three-way valve. The present invention provides a bellows for a valve device having excellent durability.

[0002]

[Background of device]

 A three-way valve that is installed in a culture tank for culturing various microorganisms and plant cells and controls the supply and discharge of the culture solution into the culture tank has a function to reliably prevent foreign substances from entering the culture solution. In addition, a function that does not corrode the inside of the culture solution and a function that reliably prevents the culture solution from leaking are required. As a three-way valve having such a function, one having a structure as shown in FIG. 3 is considered.

A first supply / discharge port 2, a second supply / discharge port 3, and a third supply / discharge port 4 are provided on the side surface of the casing 1 that constitutes the three-way valve. Further, inside the casing 1, a first valve seat 5 is provided between the first supply / discharge port 2 and the second supply / discharge port 3 and the first supply / discharge port 2 and the third valve seat 3 are provided. Second valve seats 6 are provided between the supply / discharge port 4 of the above. In addition, the first and second valve bodies 7 and 8 are provided inside the casing 1, and one surface of each valve body 7 and 8 (the surface on the first and second supply / discharge ports 2 and 3 side) is provided. ) Is opposed to the valve seats 5 and 6 described above.

On the other surfaces of the valve bodies 7 and 8 (side surfaces opposite to the first and second supply / discharge ports 2 and 3), the base end portions of the first and second rods 9 and 10 are provided. Are fixed together, and the tips of the first and second rods 9 and 10 are projected from the end surface of the casing 1. Further, the first and second air cylinders 11 and 12 are fixed to both outer end surfaces of the casing 1, and the output rods 13 and 13 of the air cylinders 11 and 12 and the front end portions of the rods 9 and 10 are fixed. Are combined with.

For example, when the first and second supply / discharge ports 2 and 3 are communicated with each other, the output rod 13 of the first air cylinder 11 is retracted and the first valve 9 is used to insert the first valve. The body 7 is pulled to separate the first valve body 7 from the first valve seat 5. At this time, while the output rod 13 of the second air cylinder 12 is in a protruding state, the second valve body 8 is pushed through the second rod 10 and the second valve body 8 is moved to the second valve seat 6 Press on. On the contrary, when the first and third supply / discharge ports 2 and 4 are communicated with each other, the first valve body 7 is pressed against the first valve seat 5 and the second valve body 8 is connected to the first valve body 7. Separate it from the second valve seat 6.

Between the first and second valve bodies 7 and 8 and the end plates 14 and 14 which form the end wall of the casing 1, the peripheral portions of the first and second rods 9 and 10 are Bellows 15, 15 are provided to prevent the culture solution from leaking from the portions where the first and second rods 9, 10 penetrate the end plates 14, 14.

By the way, it is necessary that the above-mentioned bellows 15 and 15 are not corroded by a culture solution or the like. This is because the bellows 15 and 15 are corroded by the culture solution and the corrosion products mixed in the culture solution may adversely affect the culture results. For this reason, the present inventor first considered making the main body of the bellows 15, 15 from stainless steel and coating the surface of this main body with a corrosion-resistant coating made of polytetrafluoroethylene (PTFE).

However, it is difficult to coat the surface of stainless steel with PTFE, and the corrosion resistance film has insufficient peel resistance.

[0009]

[Process leading up to the invention]

 Therefore, the present inventor considered the bellows for a valve device shown in FIG. 4 before devising the bellows for a valve device of the present invention. The bellows 16 is formed in a tubular shape from PTFE, which has excellent acid resistance and alkali resistance. An outward flange-shaped portion 17 is provided at one end (the left end in FIG. 4) of the bellows 16, and the outward flange-shaped portion 17 can be sandwiched between the end edge of the casing 1 and the end plate 14. Further, the other end portion (right end portion in FIG. 4) of the bellows 16 has the first valve body 7 (or the second valve body 8) internally formed therein. The first valve body 7 (or the second valve body 8) is provided at the end portion of the first rod 9 (or the second rod 10), and the first valve body 7 (or the second valve body 8) is provided. The side surface of the second valve body 8) opposite to the first supply / discharge port 3 (or the second supply / discharge port 4) is tightly fitted inside the other end of the bellows 16.

Further, in the middle portion of the bellows 16, a plurality of inner concave grooves 18, 18 that open to the inner peripheral surface of the middle portion are formed at equal pitches, and also open to the outer peripheral surface of the middle portion. The plurality of outer recessed grooves 19, 19 are formed at a pitch equal to the above pitch and offset from the inner recessed grooves 18, 18 in the axial direction by ½ of this pitch. The bottoms of the inner and outer recessed grooves 18 and 19 are V-shaped in cross section.

As a result of the above-mentioned configuration, the bellows 16 is crushed by the external force in the axial direction (left and right direction in FIG. 4), so that the inner and outer concave grooves 18 and 19 are crushed. The intermediate part is in a contracted state. When no external force is applied, the inner and outer recessed grooves 18 and 19 are opened as shown in the figure, and the intermediate portion is expanded to its original state. Therefore, if the bellows 16 is bridged between the end edge of the casing 1 and the end plate 14 and assembled in a state of covering the peripheral portion of the first rod 9 (or the second rod 10), While allowing the displacement of the rod 9 (or the second rod 10) of the first rod 9 (or the second rod 10) by expanding and contracting the intermediate portion, the culture is started from the portion where the first rod 9 (or the second rod 10) penetrates the end plate 14 It is possible to prevent leakage of liquid and the like.

Since the bellows 16 configured and functioning as described above is made of PTFE, sufficient corrosion resistance can be obtained without peeling of the corrosion resistant film.

However, the bellows 16 has the following disadvantages due to its shape. For example, when the bellows 16 is incorporated into the three-way valve constituting the culture device shown in FIG. 3, the surface of the bellows 16 is in contact with the culture solution used for the culture work. Depending on the type of culture solution, there are some that precipitate hard minute crystals with changes in temperature or concentration. When such a culture solution that precipitates crystals contacts the surface of the bellows 16, The hard minute crystals may enter the bottoms of the outer grooves 19, 19 in the middle of the bellows 16. Further, even if the fluid is a fluid other than the culture solution, if a hard minute foreign matter is mixed in the fluid for some reason, the foreign matter may enter the bottom of the outer concave grooves 19, 19.

In this way, the first rod 9 (or the second rod 10) is fed with the hard minute crystals or foreign matter 23 (FIG. 5) entering the bottom of the outer concave grooves 19, 19. When the bellows 16 is contracted by displacing the exhaust port 2 (3) so as to be closed, the presence of the crystal or the foreign matter 23 causes a part of the side portions 20 and 20 having a V-shaped cross-section that constitute the outer groove 19. Excessive stress may be applied and the part may be damaged.

The bellows for a valve device of the present invention has been conceived in view of the above-mentioned circumstances, and it is not corroded by a circulating fluid, and is not damaged by hard minute crystals or foreign matters. It is intended to provide a bellows for a valve device which has excellent durability and which is not likely to be caused.

[0016]

[Means for solving the problem]

 The bellows for a valve device of the present invention, like the above-mentioned conventional bellows for a valve device, is provided so as to penetrate through the end wall of the casing, and pushes and pulls a rod having a valve element at one end located inside the casing. In some cases, the valve device is opened and closed so as to be bridged between the end wall and the valve body, and is installed in a state of covering the peripheral portion of the rod.

Particularly, in the bellows for a valve device of the present invention, the bellows is made of a material having corrosion resistance, is formed in the middle portion at equal pitches, and is opened to the inner peripheral surface side of the middle portion. A plurality of inner concave grooves and a plurality of outer concave grooves formed at the same pitch as the above-mentioned pitch and shifted in the axial direction by ½ of this pitch with respect to the inner concave grooves and opening toward the outer peripheral surface of the intermediate portion. It has a groove. The bottom of the inner groove is V-shaped in cross section, and the bottom of the outer groove is arcuate in cross section.

[0018]

[Action]

 With the valve device bellows of the present invention configured as described above, the action itself in preventing fluid leakage is the same as that of the conventional valve device bellows described above.

However, since the entire bellows for a valve device of the present invention is made of a material having corrosion resistance, sufficient corrosion resistance can be obtained without the corrosion resistant film peeling off.

Further, the bottom of the inner groove is V-shaped in cross section so that the bellows can be contracted, and the bottom of the outer groove is arcuate in cross section. Even if the bellows contracts with the hard crystal or foreign matter still inside, the hard crystal or foreign matter does not come into contact with the side portion forming the outer groove, or they come into contact with each other. Even if this happens, no excessive stress is applied to this abutting part.

Therefore, it is possible to prevent the bellows from being damaged by the presence of the hard crystal or the foreign matter, and the durability is improved.

[0022]

【Example】

 Next, the case where the embodiment of the present invention shown in FIGS. 1 and 2 is applied to the three-way valve shown in FIG. 3 will be described. The bellows for a valve device according to the present invention is similar to the above-mentioned conventional bellows for a valve device, and as shown in FIG. 3, end plates 14, 14 of a three-way valve for opening and closing the first and second supply / discharge ports 2, 3. The first and second rods 9 and 10 are installed in a state of being bridged between the first and second valve bodies 7 and 8 and covering the peripheral portions of the first and second rods 9 and 10. A fluid such as a culture solution is prevented from leaking from a portion penetrating the end plates 14, 14.

The bellows for a valve device of the present invention as described above is entirely made of a material having corrosion resistance. For example, polytetrafluoroethylene (PTFE) is preferably used because it is excellent in both acid resistance and alkali resistance.

At one end (the left end in FIG. 1) of the valve device bellows of the present invention, which is formed into a cylindrical shape by the above-mentioned materials, an end plate that constitutes the end edge and the end wall of the casing 1 (FIG. 3) is provided. An outward flange-shaped portion 17 is provided so as to be sandwiched between the outer flange portion 17 and the outer flange portion 14. The other end (the right end in FIG. 1) is provided on one side (first and second feeds) of the first and second valve bodies 7 and 8 provided at the ends of the first and second rods 9 and 10, respectively. The side faces opposite to the outlets 3 and 4) can be tightly fitted inside.

Further, inner concave grooves 21, 21 are provided in an intermediate portion located between the outward flange-like portion 17 and the other end portion into which the first and second valve bodies 7, 8 can be freely fitted. And a plurality of outer concave grooves 22 and 22 are formed.

Among these, the inner concave grooves 21, 21 are formed at equal pitches with each other in a state of opening on the inner peripheral surface of the intermediate portion. On the other hand, the outer concave grooves 22, 22 are formed at a pitch equal to the above pitch in a state of opening on the outer peripheral surface of the intermediate portion. However, the outer concave grooves 22 and 22 are formed so as to be offset from the inner concave grooves 21 and 21 by ½ of the pitch in the axial direction (left and right direction in FIG. 1). Further, the bottoms of the inner recessed grooves 21, 21 are V-shaped in cross section, and the bottoms of the outer recessed grooves 22, 22 are arcuate in cross section.

As a result of being configured as described above, when the external force in the axial direction is applied to the bellows for a valve device of the present invention, the inner concave grooves 21, 21 are crushed and the opening portions of the outer concave grooves 22, 22 are formed. Becomes narrower and the bellows contract. When the external force is not applied, the inner and outer concave grooves 21 and 22 are opened as shown in FIGS. 1 and 2, and the original portions are expanded. Therefore, if the bellows for a valve device of the present invention is hung between the end edge of the casing 1 and the end plate 14 and installed in a state of covering the peripheral portion of the first rod 9 (or the second rod 10). While permitting the displacement of the first rod 9 (or the second rod 10) by the expansion and contraction of the intermediate portion, the first rod 9 (or the second rod 10) is moved by the end plate 14 It is possible to prevent the culture solution from leaking from the part that penetrates the cell.

Further, in the bellows for a valve device of the present invention, since the whole is made of a material having corrosion resistance such as PTFE, sufficient corrosion resistance can be obtained without peeling of the corrosion resistant film.

The operation described above is the same as that of the bellows 16 shown in FIG. 4, but in addition, in the bellows for a valve device of the present invention, the bottom portions of the outer concave grooves 22, 22 are cross-sectioned. Since it has an arcuate shape, a hard crystal or foreign matter 23 (FIG. 5) enters this bottom portion, and even if the bellows contracts in this state, the bellows will not be damaged. That is, when the bellows contracts with the above-mentioned crystals or foreign matter 23 in the outer grooves 22, 22, the openings of the outer grooves 22, 22 are narrowed to form the outer grooves 22, 22. Since the side portions 20 and 20 to be contacted only come close to each other and the side portions 20 and 20 do not come into contact with each other, the side portions 20 and 20 that form the crystal or foreign matter 23 and the outer concave grooves 22 and 22. Does not abut, or even if they abut, excessive stress is not applied to this abutting part.

Therefore, the bellows are prevented from being damaged by the presence of the crystals or the foreign matter 23, and the durability is improved. However, although the bellows for a valve device of the present invention has a slightly smaller amount of contraction than the bellows 16 shown in FIG. 4 due to the bottoms of the outer recessed grooves 22, 22 being arcuate in section. , This is not a practical obstacle.

Although the bellows for a valve device according to the present invention is applied to a three-way valve for a culture device in this embodiment, the bellows for a valve device according to the present invention can be applied to other devices. Of course, it can be applied to various valve devices incorporated.

[0032]

[Effect of device]

 Since the bellows for a valve device according to the present invention is constructed and operates as described above, it has sufficient corrosion resistance and is prevented from being damaged by the inclusion of foreign matter, so that the durability is improved. As a result, the reliability of the entire valve device is improved. The property is improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing the present invention.

FIG. 2 is an enlarged cross-sectional view of part A in FIG.

FIG. 3 is a sectional view of a three-way valve to which the present invention is applied.

FIG. 4 is a cross-sectional view showing a bellows for a valve device conceived prior to the present invention.

5 is an enlarged sectional view of a B part in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 2 First supply / discharge port 3 Second supply / discharge port 4 Third supply / discharge port 5 First valve seat 6 Second valve seat 7 First valve body 8 Second valve body 9 First Rod 10 second rod 11 first air cylinder 12 second air cylinder 13 output rod 14 end plate 15 bellows 16 bellows 17 outward flange-like portion 18 inner concave groove 19 outer concave groove 20 side 21 inner concave groove 22 Outer groove 23 Crystal or foreign material

Claims (1)

[Scope of utility model registration request] 1. An end wall of the casing is provided so as to penetrate therethrough,
A state in which a rod provided with a valve element at one end located inside the casing is pushed and pulled to bridge the end wall of the valve device that opens and closes the flow path and the valve element to cover a peripheral portion of the rod. A bellows for a valve device incorporated in
In a tubular shape made of a material having corrosion resistance, the intermediate portion thereof is formed at an equal pitch, and a plurality of inner concave grooves open to the inner peripheral surface of the intermediate portion, and at a pitch equal to the pitch,
And a plurality of outer concave grooves which are formed in a state of being displaced in the axial direction by ½ of this pitch with respect to the inner concave groove and open to the outer peripheral surface side of the intermediate portion, and the bottom portion of the inner concave groove has a cross section V A bellows for a valve device, which is V-shaped and in which the bottom of the outer concave groove has an arc-shaped cross section.