JPH10318383A - Valve and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce parts in number, improve its assemblage, and lower its costs down in a valve made of resin, and provided with a rotary member and a valve body. SOLUTION: This valve is provided with a rotary member composed of a stem 51, a valve part 52, and of a shaft part 53, and with a valve body 6 holding the aforesaid rotary member 5 in such a way as to be freely rotated. The sealing seat surface 66 of the valve body 6 is piled up the sealing surface 55 of the valve body 52 in such a way that they can be hermetically closed, and slid. A nut body 7 is screwed in a screw shaft part 58 provided for the rotary member 5, and the nut body 7 is thereby fastened, so that bearing stress between the sealing surface 55 and the sealing seat surface 66 is thereby increased. In this valve, the rotary member 5 is set up in a metallic mold as a core, molding resin is injected into a space formed around the aforesaid core so as to allow the valve body 6 to be integrally formed out of synthetic resin by means of injection molding. The rotary member 5 and the valve body 6 are preferably made out of PTEF and PFA.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a valve and a method for manufacturing the same.

[0002]

2. Description of the Related Art In a valve in which a communication passage provided in a valve or a valve portion is disconnected from an inlet passage or an outlet passage provided in a valve body by rotation of the valve portion, a semiconductor, a liquid crystal or the like is used. The material used in the manufacture of the resin is made of fluororesin from the viewpoint of cleanliness.

Conventionally, this type of fluorine resin valve has been
The valve portion, the valve stem, the valve body, and the like are separately manufactured by machining and then assembled, and the sealing of the sliding portion is achieved by interposing a sealing member in the sliding portion.

[0004]

However, if individual parts are manufactured through machining or a sealing member is used to ensure the sealing property, the number of assembly steps is increased, and an extra sealing member is required. In addition to problems, there were many problems in terms of assembly workability and cost.

The present invention has been made in view of the above circumstances, and has as its object to provide a valve which requires a small number of parts, is excellent in productivity and economical efficiency, and a method of manufacturing the valve.

[0006]

According to a first aspect of the invention, there is provided a valve having a truncated cone-shaped valve portion provided with a communication passage, the diameter of which is smaller than the diameter of the larger diameter end. Valve stems of different diameters
A shaft portion having a diameter not larger than the diameter of the small-diameter end portion at the small-diameter side end portion holds a rotating member coaxially protruding, and the rotatable member is rotatably held around its axis, and A valve body formed of an integral molded body of synthetic resin having an inlet passage and an outlet passage that are interrupted by the rotation of the valve portion to communicate with the communication passage, the entire outer peripheral surface of the valve portion being a sealing surface, A seal seating surface formed on the inner surface of the valve body is slidably overlapped on the entirety of the seal surface, and the valve body has a large-diameter end of the valve portion, the valve stem, A first bearing portion for rotatably supporting the valve stem by filling the stepped portion formed in the corner formed by the above, and filling a recess formed by the small-diameter end of the valve portion and the shaft portion. And penetrates the shaft to rotatably support it A second bearing section is provided,
That is.

[0007] In the valve according to the present invention, since the valve body is formed of an integrally molded synthetic resin, the valve body is formed of one part. In addition, since the seal seat surface formed on the inner surface of the valve body and the seal surface formed by the entire outer peripheral surface of the valve portion are slidably overlapped with each other, the seal member described at the beginning is used. Despite the absence, the sealing performance of the sliding part is ensured.
Furthermore, the valve according to the present invention includes a first valve body.
The bearing portion and the second bearing portion prevent the displacement of the valve portion in the axial direction.

According to a second aspect of the present invention, there is provided a valve according to the first aspect, wherein a screw shaft portion protrudes coaxially with the shaft portion of the rotating member, and an end face of the second bearing portion. Is formed as a receiving surface, and a pressing surface provided on a nut body screwed into the screw shaft portion is slidably overlapped on the receiving surface, and the valve body is tightened by tightening the nut body. It is desirable to adopt a configuration in which a seal surface is pressed against the seal seat surface of the valve body.

According to the present invention, since the sealing surface of the valve portion is pressed against the sealing surface of the valve body by tightening the nut body, a uniform surface is formed over the entire overlapping area between the sealing surface and the sealing surface. Pressure is generated, and high sealing performance is exhibited.

The valve according to the third aspect of the present invention is provided with a communication path and the same cross-sectional diameter at an arbitrary position in the axial direction. A valve stem having a smaller diameter than the other has a shaft member having a diameter smaller than the diameter of the other end at the other end in the axial direction. A valve body formed of a synthetic resin integrally molded body having an inlet passage and an outlet passage which are rotatably held around and which are interrupted by the rotation of the valve portion to communicate with the communication passage, and an outer periphery of the valve portion. The entire surface is a sealing surface, and a sealing seat surface formed on the inner surface of the valve body is overlapped with the entire sealing surface so as to be able to slide and hermetically close. Formed by one end and the valve stem A first bearing portion that embeds the formed corner-shaped step portion to rotatably support the valve stem, and a corner-shaped step portion formed by the other end of the valve portion and the shaft portion. A second buried and rotatably supported through the shaft portion
And a bearing portion.

According to a fourth aspect of the present invention, there is provided a valve provided with a communication passage and having a frusto-conical neck at one end in the axial direction and the other end in the axial direction. A valve stem with a diameter not larger than the tip diameter, a shaft part with a diameter not larger than the tip diameter of the other end at the other end, a rotating member protruding coaxially, and this rotating member around the axis thereof A valve body formed of an integrally molded synthetic resin body having an inlet passage and an outlet passage which are rotatably held and communicated with the communication passage by the rotation of the valve portion. The whole is a sealing surface, and a sealing seat surface formed on the inner surface of the valve body is overlapped with the entire sealing surface so as to be able to seal and slide, and one end portion of the valve portion is provided on the valve body. With the above valve stem A first bearing portion that fills the formed recess portion and rotatably supports the valve stem, and a recess formed by the other end portion of the valve portion and the shaft portion, and penetrates the shaft portion. And a second bearing portion rotatably supported.

According to the third and fourth aspects of the invention, as in the first aspect of the invention, the valve body is formed of one part and the sealing member described at the beginning is used. Despite the absence, the sealing performance of the sliding portion is ensured, and the first bearing portion and the second bearing portion of the valve body prevent displacement of the valve portion in the axial direction.

According to a fifth aspect of the present invention, there is provided a valve according to any one of the first, second, third and fourth aspects, wherein the rotating member comprises the valve stem and the valve portion. And an integral molded body of a synthetic resin having the shaft portion.

According to the present invention, similarly to the above-described valve body, the rotating member is formed of one part.

According to a sixth aspect of the present invention, there is provided a valve according to any one of the first, second, third, fourth and fifth aspects of the invention.
Each of the inner surface of the bearing portion and the outer surface of the valve stem overlapping the inner surface is provided with a recessed portion that cooperates with each other to form an annular enclosed space, and a peripheral wall surface of the enclosed space is provided. An annular sealing material having elasticity housed and held in the closed space is slidably adhered to the whole.

According to a seventh aspect of the present invention, there is provided a valve according to any one of the first, second, third, fourth, and fifth aspects, wherein the second part of the valve body is provided.
Each of the inner surface of the bearing portion and the outer surface of the shaft portion overlapping the inner surface is provided with a recessed portion that cooperates with each other to form an annular enclosed space, and a peripheral wall surface of the enclosed space is provided. An annular sealing material having elasticity housed and held in the closed space is slidably adhered to the whole. According to the invention as set forth in claim 6 or claim 7, the seal between the outer surface of the valve stem and the inner surface of the first bearing portion of the valve body, and the outer surface of the magnetic domain portion and the valve body are formed by the annular sealing material. The sealing performance between the second bearing portion and the inner surface of the second bearing portion is improved.

The valves of the inventions described above can be easily and economically manufactured by the valve manufacturing method according to the method of the present invention. According to this manufacturing method, as described in claim 11, a valve stem that forms a first concave portion at one end in the axial direction of a valve portion provided with a communication passage is provided coaxially with the one end portion. A first core is set in a mold as a first core having a shaft portion coaxially projecting with a shaft portion forming a second concave portion at a location connected to the other end portion at the other end portion in the axial direction of the valve stem. At the same time, a second core for forming an inlet passage and an outlet passage is set in the mold, and a molding resin is injected into a molding space around the first core and the second core, whereby An inlet passage and an outlet passage that are cut off from the communication passage by rotation of a valve portion, a first bearing portion that fills the first recess and rotatably supports the valve stem, and a second bearing portion.
A valve body having a second bearing portion that fills the recess and rotatably supports the shaft portion by penetrating the shaft portion is integrally injection-molded with a synthetic resin.

The valve according to the invention described in claim 8 is the valve according to any one of claim 1, claim 2, claim 3, claim 4, claim 5, claim 6, and claim 7, The melting point of the material forming the rotating member is equal to or higher than the melting point of the synthetic resin forming the valve body.

According to the present invention, when the valve body is manufactured in accordance with the method of the present invention, there is no possibility that the valve body molded in the molding space is fused to the rotating member set in the mold as the first core at all. Alternatively, the possibility is small. Therefore, the valve can be easily manufactured by molding the valve body. Here, the material forming the rotating member may be a synthetic resin, ceramics, or metal.

According to a ninth aspect of the present invention, there is provided the valve according to any one of the fifth, sixth, seventh and eighth aspects, wherein the synthetic resin forming the rotary member is formed. The molding shrinkage of the synthetic resin forming the valve body is larger than the shrinkage.
According to the present invention, when manufactured according to the method of the present invention, the sealing property of the overlapping portion between the seal seat surface of the valve body and the seal surface of the valve portion is further enhanced by the shrinkage of the synthetic resin forming the valve body after molding. . Therefore,
This valve exhibits high sealing performance. Note that the molding shrinkage of the synthetic resin or the molding resin refers to the shrinkage before and after molding due to curing after injection molding with the resin.

According to a tenth aspect of the present invention, there is provided a valve according to any one of the first, second, third, fourth, sixth, seventh and eighth aspects.
The rotating member is formed of a material selected from PTFE, ceramics, and metal, and the valve body is formed of a synthetic resin selected from a fluorine-based resin or another thermoplastic resin. The fluororesins include "PFA", "FEP", "PVdF", and other thermoplastic resins include "PP", "PE", "P
PS, PEEK, PES, PA, and POM. "PTFE" is a polytetrafluoroethylene resin, "PFA" is a perfluoroalkoxy fluororesin, "FEP" is fluorinated ethylene propylene, "PVd
“F” is polyvinylidene fluoride, “PP” is polypropylene resin, “PE” is polyethylene resin, “PPS”
Is a polyphenylsulfide resin, “PEEK” is a polyetheretherketone resin, “PES” is a polyethersulfone resin, “PA” is a polyamide resin, “PO”
"M" is an abbreviation for polyacetal resin. The above “ceramics” includes Al ₂ O ₃ and SiC.

[0022]

FIG. 1 is a longitudinal sectional view showing an embodiment of a valve according to the first and second aspects of the present invention, FIG. 2 is a view taken in the direction of arrow II in FIG. 1, and FIG. 1 is a view as seen in the direction of arrow III, and FIG. 4 is a view as viewed in the direction of arrow IV in FIG.

In this valve, the rotating member 5 includes a frusto-conical valve part 52, a cylindrical valve stem 51 protruding coaxially from the large-diameter end of the valve part 52, The valve member 52 is provided with a communication passage 54 orthogonal to the axis of the rotating member 5. The integral member is made of PTFE and has a shaft portion 53 coaxially protruded from a small-diameter end. The diameter of the valve stem 51 is smaller than the diameter of the large-diameter end of the valve part 52, and
The diameter of 3 is the same as the diameter of the small-diameter end of the valve section 52.
In addition, the diameter of the shaft portion 53 may be smaller than the diameter of the small-diameter end portion of the valve portion 52. In the rotating member 5, the outer peripheral surface of the valve portion 52 is a sealing surface 55, and the sealing surface 55 is finished to a predetermined surface roughness by machining.

The valve body 6 includes a body 61 around the valve 52, a first bearing 62 projecting from the body 61 and surrounding the valve rod 51,
It is an integrally molded PFA having a second bearing portion 63 that penetrates the shaft portion 53 and rotatably supports, and sleeve portions 64 and 65 protruding forward and rearward of the body main body portion 61. In this valve body 6, the inner peripheral surface of the body main portion 61 is a seal seat surface 66, and overlaps the seal surface 55 of the valve portion 52 in a slidable manner. In addition, while the stepped portion 56 formed by the large diameter end of the valve portion 52 and the valve rod 51 is buried in the first bearing portion 62, the diameter of the valve portion 52 is reduced. Small side end and shaft 5
3 form the second bearing 6
It is filled with 3. 2 and 3, a bulging portion 60 is provided at an intermediate portion of the outer peripheral portion 61 of the valve body 6. The bulged portion 60 may be omitted as long as a sealing property can be obtained.

The sleeve portions 64 and 65 are provided with an inlet passage 6.
7 and an outlet passage 68 are provided.
The communication of the communication passage 54 with the communication passage 54 is interrupted by the rotation of the valve portion 52.

A screw shaft 58 projects coaxially with the shaft 53. Further, the end surface of the second bearing portion 63 is
9, the receiving surface 69 has an annular pressing surface 7 provided on the nut body 7 screwed into the screw shaft portion 58.
1 are slidably overlapped. The tightening of the nut body 7 presses the seal surface 55 of the valve portion 52 against the seal seat surface 66 of the valve body 6.
For this reason, a uniform surface pressure is generated in the entire overlapping area between the seal surface 55 and the seal seat surface 66, thereby ensuring high sealing performance. A set screw 72 is screwed between the screw shaft portion 58 and the nut body 7, and the set screw 72 prevents the nut body 7 from loosening, thereby preventing the above-mentioned surface pressure from being reduced.

In the valve described with reference to FIGS. 1 to 4, the material forming the rotating member 5 is PTFE, and the synthetic resin forming the valve body 6 is PFA. Therefore, the melting point of the material forming the rotating member 5 is higher than the melting point of the synthetic resin forming the valve body 6. Further, the molding shrinkage of the synthetic resin forming the valve body 6 is greater than the molding shrinkage of the synthetic resin forming the rotating member 5.

In this valve, the rotating member 5 and the valve body 6 used in the valve are not formed by combining several kinds of members, but are formed as one body. Therefore, this valve has one rotating member 5.
And one valve body 6. In addition, since the seal seat surface 66 of the valve body 6 and the seal surface 55 of the valve portion 52 overlap in a sealingly slidable manner, the sealing property at the overlapping portion is ensured without using a valve seat or a seal ring. I have. Moreover, the sealing surface 55 and the sealing seat surface 6
Since a uniform surface pressure is generated in the entire area of the overlap with 6, a higher sealing property is ensured.

FIG. 5 is a longitudinal sectional view showing an embodiment of the valve according to the third aspect of the present invention. In this valve, the form of the valve portion 52, the seal surface 55 of the valve portion 52, the seal seat surface 66 of the valve body 6, and the like are different from those of the valve described with reference to FIGS. That is, in the valve of FIG. 5, the valve portion 52 has a regular cylindrical shape having the same cross-sectional diameter at an arbitrary position in the axial direction. Also, the diameter of the valve stem 51 protruding coaxially from one axial end of the valve portion 52,
A shaft 53 projecting coaxially from the other axial end of the valve 52
Is smaller than the diameter of one end or the other end of the valve portion 52. Then, the first bearing portion 6 of the valve body 6
2 fills a corner-shaped step formed by one end of the valve portion 52 and the valve rod 51, while the second bearing portion 63
The corner 57a formed by the other end of the valve 52 and the shaft 53 is filled. Other items are the same as those of the valve described with reference to FIGS.

FIG. 6 is a longitudinal sectional view showing an embodiment of the valve according to the fourth aspect of the present invention. Also in this valve, the form of the valve portion 52, the seal surface 55 of the valve portion 52, the seal seat surface 66 of the valve body 6, and the like are different from those of the valve described with reference to FIGS. That is, in the valve of FIG. 6, the valve portion 52 has tapered frustoconical neck portions 52a and 52b at one axial end and the other axial end. Also,
At one end of the valve portion 52, a valve stem 51 having the same diameter as the tip diameter of the one end portion, and at the other end, a shaft portion 53 having the same diameter as the tip diameter of the other end portion are projected coaxially. Then, the first bearing portion 62 of the valve body 6 is formed by the concave portion 5 formed by one end of the valve portion 52 and the valve rod 51.
6b, while the second bearing 63 fills a recess 57b formed by the other end of the valve 52 and the shaft 53. Other items are the same as those of the valve described with reference to FIGS.

In the valve described with reference to FIGS. 5 and 6,
It is composed of two parts, one rotating member 5 and one valve body 6. In addition, since the seal seat surface 66 of the valve body 6 and the seal surface 55 of the valve portion 52 overlap in a sealingly slidable manner, the sealing property at the overlapping portion is ensured without using a valve seat or a seal ring. I have.

Each of the valves described with reference to FIGS. 1 to 4 can be manufactured by a manufacturing method described below as an example.
That is, as shown in FIG. 7, a rotating member 5 made of an integrally molded body of PTFE is formed in advance, and the rotating member 5 is
As a core 110, an injection molding die 1 having a molding surface 101 on which the outer contour of the valve body 6 can be molded.
Set to 00. In addition, the mold 1 is used as the first core 110.
In the rotating member 5 set to 00, the step 56 described with reference to FIG. 1 corresponds to the first recess 81, and the recess 57 corresponds to the second recess 82. Rotating member 5 is connected to first core 11
At the same time, the second core 120 made of metal is inserted into the communication passage 54 provided in the valve portion 52 of the rotating member 5 so that the second core 120 made of metal is inserted into the communication passage 54. The second core 120 is prevented so that the molding resin is prevented from entering, and the inlet passage 67 and the outlet passage 68 of the valve body 6 can be formed by the second core 120.
Is set in the mold 100. Further, the third metal cores 130 and 140 having a molding surface for molding the inner peripheral surfaces of the sleeve portions 64 and 65 are attached to the second core 120.
And set in the mold 100.

Thus, the rotating member 5 used as the first core 110 is kept at room temperature or preheated to the mold temperature, and the first core 110, the second core 120, and the third core PFA in a molten state, which is a molding resin for molding the valve body 6, is injected into a molding space S formed around 130 and 140, and after a certain cooling time, the PFA is cured and Remove from mold 100. In this way, the body 61, the first bearing 62, the second bearing 63, and the sleeves 64, 65 having the inlet passage 67 and the outlet passage 68 described with reference to FIGS.
It is molded as an integral molded body of FA.

When such a manufacturing method is performed, the first core 1
PT, which is the material of the rotating member 5 used as 10
The melting point of FE is PFA which is a molding material of the valve body 6.
, The valve body 6 is molded without fusion during injection molding. Moreover, PTF
Since the molding shrinkage of PFA is larger than the molding shrinkage of E, after injection molding, the valve seat 52 of the valve body 6 made of PTFE is made of the seal seating surface 66 of the valve body 6 made of PFA.
The sealing surface 55 surely comes into close contact with the sealing surface 55, which helps to improve the sealing performance at the overlapping portion between the sealing seat surface 66 and the sealing surface 55.

In the method of manufacturing the valve described with reference to FIGS. 1 to 6 and the valve described with reference to FIG. 7, PTFE is used for the material of the rotating member 5 and PFA is used for the molding material of the valve body 6. The same synthetic resin can be used for the material of the rotating member 5 and the valve body 6.
And the valve body 6 have the same melting point. Even when the melting point of the rotating member 5 and that of the valve body 6 are the same, when the valve body 6 is injection-molded, the molding material of the valve body 6 is applied to the rotating member 5 used as the first core 110. Fusing is unlikely to occur. This is because both resins do not fuse even if the molten resin touches the cooled resin.

In the method of manufacturing the valve described with reference to FIGS. 1 to 6 and the valve described with reference to FIG. 7, various materials can be selected as the material of the rotating member 5 and the material of the valve body 6. Specifically, as the material of the rotating member 5, besides the above-mentioned PTFE, ceramics or metal can be used.
In addition to FA, fluorine-based resins such as FEP and PVdF and P
A synthetic resin selected from other thermoplastic resins such as P, PE, PPS, PEEK, PES, PA, and POM can be used.

When a synthetic resin such as PTFE is used as the material of the rotating member 5, the maximum value of the surface roughness Rmax is used.
Has been confirmed to be able to secure a high degree of the above-mentioned sealing performance when processed to 8 μm or less. Further, when ceramics or metal is used as the material of the rotating member 5, if the maximum value Rmax of the surface roughness is processed to 2.3 μm or less, the above-mentioned high sealing performance can be secured, and furthermore, a long term It has been confirmed that when the passage is repeatedly opened and closed over a period of time, the abrasion of the inner surface 65 of the valve body 6 as the counterpart is suppressed, and the seal reliability is enhanced.

In a valve manufactured by using the valve manufacturing method according to the present invention, the sealing property at the overlapping portion between the seal seat surface 66 of the valve body 6 and the seal surface 55 of the valve portion 52 is determined by the body main portion. It depends on the magnitude of the holding force of the valve section 52 by the valve 61. In order to prevent the holding force from deteriorating, it is useful to form a ring-shaped bulged portion 60 as shown in FIGS. The magnitude of the holding force is related to the molding shrinkage and the tensile strength of the molding material of the valve body 6. That is, the valve body 6 formed of a synthetic resin having a large molding shrinkage has a large holding force of the valve portion 52 even if the tensile strength is small, and conversely, a valve formed of a synthetic resin having a large tensile strength. The holding force of the valve portion 52 of the body 6 is increased even if the molding shrinkage is small. For valves used in semiconductor manufacturing processes,
The shrinkage ratio of the molding material of the valve body 6 is preferably 2% or more, particularly preferably 4% or more. Such a shrinkage is satisfied by using PFA for the molding material. Further, the tensile strength of the molding material of the valve body 6 is preferably 200 kg or more, particularly preferably 300 kg or more.

Next, concrete numerical values of the molding shrinkage and the tensile strength of the synthetic resin that can be selected as the material of the valve body 6 will be described. Which material to choose depends on
It should be determined appropriately in consideration of the purpose, economy, and other conditions of the valve.

Shrinkage (%) Tensile strength (kg / cm ² ) PFA 3-5 300 PP 1-2400 PE 1-2 150 PPS 0.5-1900 PPS (with glass fiber) 0.2-0. 5 1300 PEEK 1900 PEEK (with glass fiber) 0.5 1700 PES 0.6 800 PES (with glass fiber) 0.2-0.5 1400 PA 1.5 700 POM 1.5 600

As described above, the valve of the present invention and the valve manufactured by the method of manufacturing the valve of the present invention allow the seal seat surface 66 of the valve body 6 and the seal surface 55 of the valve portion 52 to slide tightly. By overlapping, the sealing property of the overlapping portion is ensured. Next, measures for further improving the sealing property will be described.

The countermeasure shown in FIG. 6 is to cooperate with the first bearing 62 of the valve body 6 and the outer peripheral surface of the valve rod 51 overlapping the inner surface of the first bearing 62, respectively. Semicircular concave portions 92 and 93 forming an annular closed space 91 are provided, and an elastic rubber O-ring accommodated and held in the closed space 91 is provided on the entire peripheral wall surface of the closed space 81. The annular sealing material 94 is slidably adhered. The valve in which such measures are taken is used as the first core 110 described above in the mold 10.
A semicircular groove-shaped recess 93 is formed in advance on the valve rod 51 of the rotating member 5 set to 0, and the inner half of the annular sealing material 94 having a circular cross section is housed and held in the recess 93. In this state, the valve body 6 can be easily manufactured by injection molding of the valve body 6 described with reference to FIG. By adopting this manufacturing method, it is not necessary to incorporate the annular sealing material 94 into the rotating member 5 or the valve body 6 later.

When the annular sealing material 94 is housed and held in the closed space 91 as described above, the sealing performance between the rotating member 5 and the valve body 6 is enhanced by the annular sealing material 94.

[0044]

As described above, in the valve of the present invention and the valve manufactured by the manufacturing method of the present invention, the valve body is formed of a single molded body of one synthetic resin. The sealing performance is ensured by the overlap of the seal seat surface and the seal surface of the valve part of the rotating member, so the number of parts is reduced, and at the same time, the assembly workability and cost are greatly improved compared to conventional valves. . Such a valve can be easily and inexpensively manufactured by the valve manufacturing method of the present invention.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a valve according to the first and second aspects of the present invention.

FIG. 2 is a view taken in the direction of the arrow II in FIG.

FIG. 3 is a view taken in the direction of the arrow III in FIG. 1;

FIG. 4 is a view taken in the direction of the arrow IV in FIG. 1;

FIG. 5 is a longitudinal sectional view showing an embodiment of the valve according to the third aspect of the present invention.

FIG. 6 is a longitudinal sectional view showing one embodiment of the valve according to the invention described in claim 4;

FIG. 7 is a longitudinal sectional view for explaining a method of manufacturing a valve according to the present invention.

FIG. 8 is a partial longitudinal sectional view showing a measure for improving the sealing property.

[Explanation of symbols]

 Reference Signs List 5 rotating member 6 valve body 7 nut body 51 valve rod 52 valve portion 52a, 52b neck portion 53 shaft portion 54 communication passage 55 sealing surface 56 step portion 56a step portion 56b recess portion 57 recess portion 57a step portion 57b recess portion 58 screw shaft portion 62 first bearing portion 63 second bearing portion 66 seal seating surface 67 inlet passage 68 outlet passage 69 receiving surface 71 pressing surface 81 first concave portion 82 second concave portion 92, 93 concave portion 94 annular seal material 110 first core 120 Second Core

Claims (11)

[Claims] 1. A valve stem having a diameter smaller than the diameter of the large-diameter side end of the large-diameter side end of the frusto-conical valve portion having the communication passage, and the valve stem having the diameter smaller than the diameter of the large-diameter side end. A shaft portion having a diameter not larger than the diameter of the small-diameter side end portion is provided with a rotating member protruding coaxially, the rotatable member being rotatably held around its axis, and the communication passage formed by rotation of the valve portion. A valve body formed of an integral molded body of synthetic resin having an inlet passage and an outlet passage that are blocked from communicating with the valve body. The entire outer peripheral surface of the valve portion is a sealing surface, and the entire sealing surface is The seal seat surface formed on the inner surface of the valve body overlaps so that it can slide tightly,
A first bearing portion for burying a corner-shaped step formed by the large-diameter end portion of the valve portion and the valve stem in the valve body and rotatably supporting the valve stem; A second bearing portion which fills a concave portion formed by the small-diameter end portion and the shaft portion and penetrates the shaft portion to rotatably support the shaft portion. 2. A screw shaft protrudes coaxially with the shaft of the rotating member, and an end face of the second bearing is formed as a receiving surface, and the receiving shaft is screwed into the screw shaft. A pressing surface provided on the nut body is slidably overlapped with the nut body, and a seal surface of the valve portion is pressed against the seal seat surface of the valve body by tightening the nut body. 2. The valve according to 1. 3. A valve rod having a communication passage and having a diameter smaller than the diameter of one end of an axially one end portion of a regular cylindrical valve portion having the same cross-sectional diameter at an arbitrary position in the axial direction. However, at the other end in the axial direction, a shaft portion having a diameter smaller than the diameter of the other end portion, respectively, a rotating member protruding coaxially, and the rotatable member is rotatably held around its axis, and A valve body formed of an integral molded body of synthetic resin having an inlet passage and an outlet passage that are interrupted by the rotation of the valve portion to communicate with the communication passage, the entire outer peripheral surface of the valve portion being a sealing surface, A seal seating surface formed on the inner surface of the valve body is overlapped with the entirety of the sealing surface so as to be able to slide hermetically.
A first bearing portion that embeds a corner-shaped step formed by the one end portion of the valve portion and the valve stem in the valve body to rotatably support the valve stem; A valve, comprising: a second bearing portion that fills a corner-shaped step formed by the other end portion and the shaft portion and that rotatably supports the shaft portion by penetrating the shaft portion. 4. A valve having a communicating passage and having a diameter at the one end of the valve portion having a frustoconical neck at one end in the axial direction and the other end in the axial direction, the diameter being not larger than the diameter of the tip of the one end. The rod has, at its other end, a shaft part having a diameter not larger than the tip diameter of the other end, a rotating member protruding coaxially, and the rotating member rotatably holding the rotating member around its axis and the valve part. A valve body formed of an integral molded body of synthetic resin having an inlet passage and an outlet passage that are interrupted by the rotation of the communication passage, and the entire outer peripheral surface of the valve portion is a sealing surface. A seal seating surface formed on the inner surface of the valve body overlaps with the entire surface so as to be able to slide and seal, and
A first bearing portion for burying a recess formed by one end of the valve portion and the valve stem in the valve body to rotatably support the valve stem; the other end of the valve portion; and the shaft. A second bearing portion that fills a recess formed by the first portion and rotatably supports the shaft portion by penetrating the shaft portion. 5. The rotary member according to claim 1, 2 or 3, wherein the rotary member is formed of a synthetic resin body having the valve stem, the valve portion, and the shaft portion. The valve according to any one of the above. 6. A recessed portion cooperating with each other to form an annular closed space in each of an inner surface of the first bearing portion of the valve body and an outer surface of the valve stem overlapping the inner surface. Is provided, on the entire peripheral wall surface of the closed space,
The valve according to any one of claims 1, 2, 3, 4, and 5, wherein an elastic annular sealing material housed and held in the closed space is slidably adhered. 7. A recessed portion cooperating with each other to form an annular closed space in each of an inner surface of a second bearing portion of the valve body and an outer surface of the shaft portion overlapping the inner surface. Is provided, on the entire peripheral wall surface of the closed space,
The valve according to any one of claims 1, 2, 3, 4, and 5, wherein an elastic annular sealing material housed and held in the closed space is slidably adhered. 8. The method according to claim 1, wherein the melting point of the material forming the rotating member is equal to or higher than the melting point of the synthetic resin forming the valve body.
The valve according to any one of claims 4, 5, 6, and 7. 9. The molding shrinkage of the synthetic resin forming the valve body is greater than the molding shrinkage of the synthetic resin forming the rotating member. A valve according to claim 8. 10. The rotating member is formed of a material selected from PTFE, ceramics, and metal, and the valve body is formed of a synthetic resin selected from a fluorine-based resin or another thermoplastic resin. Item 1,
Claim 2, Claim 3, Claim 4, Claim 6, Claim 7,
A valve according to claim 8. 11. A valve having a communication passage, a valve stem forming a first concave portion at one end in the axial direction of a valve portion provided with a communication passage and coaxially protruding at a location connected to the one end, and the other end in the axial direction of the valve stem. A rotary member having a shaft portion coaxially protruding from the end portion forming a second concave portion at a location connected to the other end portion is set in a mold as a first core, and an inlet passage and an outlet passage are formed. By setting the second core to the mold, and injecting molding resin into the molding space around the first core and the second core, the rotation of the valve portion causes the communication passage to enter the communication passage. The inlet passage and the outlet passage that are interrupted in communication, a first bearing portion that fills the first recess and rotatably supports the valve stem,
A method of manufacturing a valve, comprising: integrally injecting and molding a valve body having a second bearing portion that fills a concave portion and rotatably supports the shaft portion by penetrating the shaft portion.