JPH1144373A - Valve and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To strengthen strength of a valve by surrounding the whole faces of reinforcement with resin forming a valve body, and integratedly burying the reinforcement in the valve body, on the part position where the valve is apt to be broken and deformed, when a load is applied to the valve body made of a resin from the outside. SOLUTION: In this ball valve 3, a valve element 31 is rotatably mounted in a valve body 2, and a metallic handle receiving part 32 is provided on the extreme end of the stem 31a of the valve element 31 so as to project from the valve body 2. A seal ring 4 is internally provided in the valve body 2. A reinforcement formed out of metal material such as stainless steel, is provided with a trumpet-shaped pipe part 52 gradually spreading on one end of a straight pipe part 51. The reinforcement 5a surrounds the female screw 22 formed part of a socket from the outside with the straight pipe part 51, surrounds the valve element 31 part of the valve body 2 from the outside with the trumpet-shaped pipe part 52, and it is buried in the valve body 2, so that it is perfectly isolated from the outside with resin constituting the valve body 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin valve and a method for manufacturing the same.

[0002]

2. Description of the Related Art Resin valves are widely used in domestic hot water supply / water supply lines and chemical liquid lines because they are excellent in corrosion resistance such as chemical resistance, can be easily manufactured and can be provided at low cost. However, in the case of a resin valve, since the valve body is molded by injection molding, a weld line is inevitably generated at a position away from the gate portion.

[0003] Since the weld line is weaker in strength than other parts and is distorted, when a load is applied from the outside, the weld line tends to be a starting point of damage. In addition, the resin valve has a receiving port provided with a tapered female screw at an end, and the pipe is connected to the receiving port by screwing a thread provided on the outer peripheral surface of the pipe end. there is are, but when you try to connect the metal tube in such a resin valve, or damaged just the socket is pushed and spread outward because of high strength of the tube, there is a risk of or cause dropout .

Accordingly, as in the valve disclosed in Japanese Utility Model Application Laid-Open No. 7-4971, a metal tightening ring is fitted on the outer peripheral surface of the connection portion of the pipe of the receiving port,
As in the valves disclosed in JP-A-133279 and JP-A-62-151472, a ring-shaped reinforcing material may be integrally provided along the female screw portion of the socket to reinforce the socket. Proposed.

[0005]

However, in the case of any of the valves disclosed in the above publications, at least a part of the tightening ring and the reinforcing material are exposed outside the valve, and the inherent corrosion resistance of the resin valve is reduced. There is a problem in point.

[0006] In view of such circumstances, an object of the present invention is to provide a valve which is more excellent in strength without impairing the corrosion resistance of a resin-made valve body, and a method of manufacturing the valve.

[0007]

SUMMARY OF THE INVENTION A valve according to the present invention (the invention according to claim 1) is a portion which is easily damaged when a load is applied from the outside of a valve body made of resin or a portion which is likely to be deformed to cause poor connection. In addition, a reinforcing material for reinforcing these portions is embedded and integrated in the valve body so that the entire surface is surrounded by the resin forming the valve body.

In the above structure, the resin forming the valve body is not particularly limited. For example, polyvinyl chloride (PVC), post-chlorinated polyvinyl chloride (CPV)
C), polyvinylidene fluoride (PVDF), polyphenylene sulfide (PPS), polypropylene (PP)
And the like. As the reinforcing material, a metal material such as iron, stainless steel, copper, or a copper alloy is usually used, but a reinforcing material made of a fiber-reinforced resin may be used.

When a metal material is used as the reinforcing material, the thickness of the reinforcing material is preferably 0.2 mm or more, and the surface thereof is subjected to a punching process or a knurling process, or a projection is provided to make the surface uneven. Is preferably provided. In addition,
The holes formed by punching (hereinafter, referred to as “punched holes”) preferably have a porosity of 10 to 80%, and the diameter of the holes is preferably φ2 to 10 mm.

Preferably, an adhesive layer is interposed between the reinforcing material and the valve body. The adhesive constituting the adhesive layer is not particularly limited, and examples thereof include a hot melt adhesive, an organic titanate, a coupling agent, and an epoxy adhesive.

The method of manufacturing a valve according to the present invention (invention of claim 2) can be applied to a portion which is easily damaged when a load is applied from the outside of a valve body made of resin or a portion which is likely to be deformed to cause poor connection. Is provided, and the entire surface of the reinforcing material is embedded and integrated so as to be surrounded by the resin forming the valve body.

In a preferred embodiment of the method for manufacturing a valve according to the present invention, the preferred embodiment comprises a plurality of molds that can be opened and closed, and when closed, forms a mold cavity corresponding to the outer shape of the valve to be molded. In a cavity of a cavity mold of an injection mold including a cavity mold and a core mold corresponding to the inner surface shape of a valve to be molded, the core mold and a valve body forming a part of the valve are reinforced. And forming a first cavity surrounded by the core mold, the valve body, and the reinforcing material,
A first step of forming an inner layer by injecting a molten resin into the first cavity to obtain a molded body; inserting the obtained molded body into the mold cavity; Forming a second cavity by injecting a molten resin into the second cavity to form an outer layer, and burying and integrating the reinforcing material so as to be surrounded by the resin. Consists of

In the above aspect, the cavity mold used in the first step and the cavity mold used in the second step may be the same or different.
When the cavity mold used in the first step and the cavity mold used in the second step are the same, in the first step, the inner mold is placed in the cavity of the cavity mold. By inserting the reinforcing member, the reinforcing material can be gripped and fixed.

In the method of manufacturing a valve according to the present invention, another preferred embodiment comprises a plurality of molds which can be opened and closed, and when closed, forms a mold cavity corresponding to the outer shape of the valve to be molded. A valve body that forms a part of a valve while advancing the core mold into a cavity of a cavity mold of an injection mold that includes a cavity mold and a core mold corresponding to an inner surface shape of a valve to be molded. And a reinforcing material are provided to form a cavity surrounded by the core mold, the valve element and the reinforcing material, and the molten material is injected into the cavity so that the reinforcing material is surrounded by the resin. A method of manufacturing a valve for molding a valve embedded and integrated in a core mold, wherein the reinforcement is detachably supported by a reinforcement support member slidably mounted on a part of the core mold. But inside the fossa When advanced, the reinforcement support member moves forward with the core mold to dispose the reinforcement in the mold cavity, and when the molten resin is injected, the reinforcement support member is retracted by the resin pressure. Thereby, the reinforcing material supporting member is detached from the reinforcing material.

[0015] By doing so, the reinforcing material supporting member recedes due to the resin pressure, and the reinforcing material is buried without being exposed on the outer surface of the molded product, so that there is no fear of deterioration of the reinforcing material. . In addition, since the injection molding is performed in one step, no interface between the resins is generated except for the weld line, the adhesive strength between the resin and the reinforcing material is increased, and intrusion of water or the like from the interface is avoided.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
The details will be described with reference to the drawings. FIG. 1 shows an embodiment of a valve according to the present invention.

As shown in FIG. 1, the valve 1a is of a ball valve type, and includes a valve body 2, a valve body (ball valve) 3 forming a part of the valve, a seal ring 4,
And a reinforcing material 5a. The valve body 2 is formed of a resin material having excellent corrosion resistance, and has sockets 21 and 2 at both ends.
1, and a female screw 22 is provided on the inner peripheral surface of the receiving port 21.

The ball valve 3 has a valve body 31 formed of a resin material having excellent corrosion resistance, and is rotatably mounted inside the valve body 2. A metal handle is attached to the tip of a stem 31a of the valve body 31. The receiving portion 32 is provided so as to protrude from the valve body 2. The seal ring 4 is provided inside the valve body 2 and is made of a resin material having excellent corrosion resistance.

As shown in FIG. 2, the reinforcing material 5a is provided with a wrapper tube portion 52 having a gradually expanding diameter at one end of a straight tube portion 51, and is formed of a metal material such as stainless steel. The valve body 2 is embedded in the valve body 2 so as to surround the portion where the female screw 22 of the receiving port 21 is formed from the outside by the 51 and surround the valve body 31 of the valve body 21 from the outside by the wrapper tube 52. It is completely isolated from the outside by the constituent resin.

The valve 1a is provided with the reinforcing material 5 as described above.
a is buried in the valve body 2, even when a metal pipe is screwed and joined to the receiving port 21, the straight pipe portion 51 of the reinforcing material 5 a causes damage or disconnection due to the expansion of the receiving port 21 and a weld line. Can prevent damage from
The wrapper tube portion 52 reinforces the vicinity of the valve body 31 accommodating portion (the outer peripheral portion of the stem) of the valve body 2 to prevent breakage from the weld line.

In addition, since the reinforcing material 5a is completely covered by the resin constituting the valve body 2, the reinforcing material 5a
a does not come into contact with the fluid flowing inside the pipe or the external atmosphere. Therefore, a material having poor corrosion resistance can be used as the reinforcing material 5a.

FIGS. 3 and 4 are cross-sectional views of an injection mold for illustrating the method of manufacturing the valve of FIG. 1 and illustrating the first step of the invention according to claim 4. FIG. FIG. 4 shows a state in which the cavity mold is closed, and FIG. 4 shows only a portion constituting an injection mold in a cross-sectional view.

3 and 4, reference numeral 7 denotes a cavity mold;
Denotes an inner mold, 73 denotes a gate provided in the cavity mold 7, 7
Reference numeral 4 denotes a gate provided in the inner die 72, 8 denotes a core die (slide core), and 91 denotes a first cavity.

The cavity mold 7 forms an injection molding mold together with core molds 8 and 8 (FIG. 4) corresponding to the inner surface shape of the valve to be molded, and is opened and closed by an injection molding machine (not shown). It consists of two possible molds which, when closed, form a mold cavity. The mold cavity corresponds to the outer shape of the bulb to be molded.

One of the cavities 7 is provided with a gate 73 which can communicate with the nozzle of the injection molding apparatus. The cavity molds 7, 7 hold reinforcing materials 5a, 5a.
An inner mold 72 that can be fixed is provided.
A gate 74 communicating with 3 is provided.

In order to form the inner layer of the valve 2, first, the cavity molds 7, 7 provided with the inner molds 72, 72 are opened, and the cavity molds 7, 7 are formed in advance by molding. The ball valve 3 is disposed and the inner dies 72, 7
2. The reinforcing members 5a, 5a are gripped and fixed to 2.

Next, as shown in FIG. 4, a cavity mold 7, 7 in which a ball valve 3 and reinforcing materials 5a, 5a are disposed in a mold cavity.
Are closed and the slide cores 8, 8 are disposed in the mold cavity, and the slide cores 8, 8, the valve body 3, and the reinforcing members 5a, 5a
A first cavity 91 surrounded by is formed. Next, a gate 73,
Through 74, the molten resin is injected into the first cavity 91 to form an inner layer.

FIGS. 5 and 6 are cross-sectional views of an injection mold for illustrating a method of manufacturing the valve of FIG. 1 and illustrating a second step of the invention according to claim 4. FIG. FIG. 6 shows a state in which the cavity mold is closed, and FIG. 6 shows a state in which the cavity mold is closed.

In FIGS. 5 and 6, reference numeral 11 denotes a molded body obtained in the first step of the present invention, and reference numeral 91 denotes a second cavity.

After the resin forming the inner layer in the first step is solidified, as shown in FIG. 5, the cavity molds 7, 7 are opened, the inner molds 72, 72 are removed, and the molded body 11 (half sectional view) is formed. ).

Next, as shown in FIG. 6, the obtained molded body 11 is fixed to the cavity molds 7, 7 by forming the cavity of the cavity molds 7, 7. And slide cores 8 are inserted. Next, when the cavity molds 7 are closed, a second cavity 92 is formed between the molded body 11 and the cavity molds 7.

Next, a molten resin is injected into the second cavity 92 from the nozzle of an injection molding machine (not shown) through the gate 73 to form an outer layer. Thus, FIG.
As described above, the valve 1a embedded and integrated so that the reinforcing members 5a, 5a are surrounded by the resin is obtained.

FIG. 7 is a partial sectional view of an injection mold for explaining the fifth aspect of the present invention.

In FIG. 7, 57 is a reinforcing member support member,
Is an elastic member, 5h is a reinforcing material, 81 is a core-type cavity mounting portion, and 82 is a core-type core portion. The injection molding die used in the invention according to claim 5 comprises a plurality of molds that can be opened and closed, as described in FIGS. 3 and 4, and the outer surface of the valve to be molded when closed. It comprises a cavity mold that forms a cavity corresponding to the shape, and a core mold that corresponds to the inner surface shape of the valve to be molded.

According to the fifth aspect of the present invention, as shown in FIG. 7, the core mold is formed into a core part 82 which forms a part of a cavity and a cavity mold (7 in FIGS. 3 and 4) when closed. And a cavity type mounting portion 81 to be mounted and fixed. The reinforcing material 5h is detachably supported by a reinforcing material supporting member 57 slidably mounted on the core portion 82.

The core molds (81, 82) are advanced into the mold cavity,
When the core molds (81, 82) are advanced into the mold cavity, the reinforcing material support member 57 is pressed by the cavity mold mounting portion 81 via the elastic member 58, and the core material (81, 82) is retracted.
h is arranged in the mold cavity (the right direction of the arrow in the figure). Then, a valve body forming a part of the valve is provided to form a cavity surrounded by the core mold and the reinforcing material.

As shown in FIG. 8, the reinforcing material supporting member 57 has a cylindrical portion 571 having substantially the same diameter as the core-type cavity die mounting portion 81, and a taper whose diameter gradually decreases in the tip direction (cavity direction). It comprises a portion 572 and a cylindrical portion 573 having an inner diameter substantially equal to the outer diameter of the reinforcing material 5h and capable of externally fitting the reinforcing material. The angle of the tapered portion 572 is preferably 30 ° or more, and the cylindrical portion 573 is preferably 1 mm or more in order to fit the reinforcing material 5h.

Next, when the molten resin (not shown) is injected into the cavity, the reinforcing material supporting member 57 is retracted by the resin pressure (in the left direction of the arrow in the figure), so that the reinforcing material supporting member 57 is moved. A valve that is detached from the reinforcing material 5h and is embedded and integrated so that the reinforcing material 5h is surrounded by the resin is formed. The reinforcing material supporting member 5
7 may be separately advanced and retracted by a hydraulic cylinder and a pneumatic cylinder in synchronization with the movement timing of the injection mold. Further, the reinforcement support member 57 may be provided with a locking projection for locking the reinforcement 5h. In this case, the locking projection may be provided on the entire circumferential direction of the reinforcing member support member 57 or may be provided on a part of the circumferential direction.

The method of manufacturing the valve according to the present invention by injection molding has been described above, but the valve can be molded in the same manner by press molding.

FIG. 9 shows another embodiment of the valve according to the present invention. As shown in FIG. 9, the valve 1b is the same as the valve 1a, except that a straight tubular reinforcing material 5b is embedded only in the receiving portions 21 and 21.

In other words, according to this valve 1b, the receiving ports 21 and 21 are reinforced by the straight tubular reinforcing material 5b. There is no increase in diameter, no breakage, and no detachment of the metal tube.

FIG. 10 shows another embodiment of the valve according to the present invention. As shown in FIG. 10, the valve 1c is the same as the valve 1a except that a plate-like reinforcing material 5c is buried only along a weld line portion near the valve body accommodating portion of the valve body 2. ing.

That is, according to the valve 1c, the reinforcing material 5c is embedded and integrated along the weld line 6 which is expected to be a starting point of breakage when a load is applied from the outside. The strength is the same as other parts, and the durability is improved.

The valve according to the present invention is not limited to the above embodiment. For example, instead of the reinforcing member 5a of the valve 1a, as shown in FIG. 11, a reinforcing member 5d in which a plurality of ring-shaped ridges 53 are provided in parallel on the outer peripheral surface of a straight pipe portion 51, or as shown in FIG. Instead of the flared tube portion 52, a reinforcing material 5e provided with a protruding piece 55 only at a portion along the weld line at one end of the straight tube portion 51 may be used.

Further, as shown in FIGS. 13 and 14, the punching holes 56 provided in the reinforcing materials 5f and 5g are not only preferable because the resin and the reinforcing materials 5f and 5g are firmly adhered to each other by an anchor effect. In this case, the flow path of the resin can be secured, and the reinforcing materials 5f and 5g do not float due to the tree finger pressure.

In the above embodiment, the valve 1
Although a, 1b and 1c are all ball valves, other types of valves such as a diaphragm type may be used.

[0047]

Embodiments of the present invention will be described below in more detail.

(Example 1) An integrally molded compact type having a shape shown in Fig. 1 comprising a polyvinyl chloride valve body, a polyvinyl chloride ball valve, a seal ring made of fluororesin, and a reinforcing material made of stainless steel. Was manufactured.

The reinforcing material of this ball valve has a wall thickness of 1.2.
It was obtained by press forming a mm stainless steel tube. In manufacturing the ball valve, first, a hot-met adhesive (Hot-melt adhesive # 236, manufactured by Sekisui Chemical Co., Ltd.) is applied to the inner and outer surfaces of the reinforcing material, and a ball valve and a preformed ball valve are used. After setting the reinforcing material together with the seal ring in the mold and forming the inner layer as described with reference to FIGS.
As described above, a two-stage molding method for molding the outer layer was used. Further, the obtained ball valve has the reinforcing material completely surrounded by the resin constituting the valve body, and the thickness of the resin layer around the reinforcing material is 0.1 mm in any part.
It was 5 mm or more.

(Example 2) In the same manner as in Example 1 except that a stainless steel pipe having a thickness of 1 mm was used as a reinforcing material, FIG.
A 25A ball valve of the integrally molded compact type having the shape shown in FIG.

(Example 3) An integrally molded compact type 2 having the shape shown in Fig. 1 in the same manner as in Example 1 except that a stainless steel plate having a width of 10 mm and a thickness of 1 mm was used as a reinforcing material.
A 5A ball valve was manufactured.

(Example 4) The shape of the valve was changed to the shape (50A) shown in FIG. 15, and the shape shown in FIG.
% Of the reinforcing material 5i subjected to the punching process
In addition, the union nut 62 is provided with the reinforcing material 5f having the shape shown in FIG.
A ball valve was manufactured in the same manner as in Example 1, except that the reinforcing material 5f having the shape shown in FIG.

(Example 5) A ball valve was manufactured in the same manner as in Example 4, except that the reinforcing material 5i was provided only in the receiving portion 61.

(Example 6) A ball valve was manufactured in the same manner as in Example 4, except that the reinforcing material 5f was provided only on the union nut 62.

Comparative Example 1 An integrally molded compact 25A ball valve without a reinforcing material was manufactured in the same manner as in Example 1 except that no reinforcing material was embedded.

Comparative Example 2 A 50A ball valve without a reinforcing material was manufactured in the same manner as in Example 4 except that no reinforcing material was embedded.

The breaking water pressure values and breaking bending loads of the ball valves obtained in Examples 1 to 6 and Comparative Examples 1 and 2 were examined, and the results are shown in Table 1. In addition, as shown in FIG. 16, as shown in FIG. 16, the short water pipes 102 and 103 whose one ends are closed with blind plates 101 are connected to the two receiving ports of the valve 100, Pressurized water (23 ° C.) was supplied from the pump P through a hole (not shown), and the water pressure when the valve 100 was broken was measured by the pressure gauge 104 to obtain the water pressure. In addition,
For Example 5 and Comparative Example 2, 0.5 to 2.5 MPa
The number of times until destruction by the pulsating flow was determined.

On the other hand, as shown in FIG. 17, the short bending tubes 201 and 202 were connected to both receiving ports of the valve 200, and the breaking bending load was measured at a position 200 mm from the center of the valve 200 (Example 6, Comparative Example). (500 mm for No. 2) was obtained by applying a load in the direction of the arrow while supporting both short tubes 201 and 202 from below.

[0059]

[Table 1]

[0060]

[Table 2]

[0061]

The valve according to the present invention is configured as described above, and therefore is superior in strength as compared with a conventional valve. Moreover, it has excellent corrosion resistance.

Since the method for manufacturing a valve according to the present invention is as described above, it is possible to obtain a valve excellent in strength and corrosion resistance without exposing the reinforcing material.

Since the method for manufacturing a valve according to the fourth aspect of the present invention is as described above, the valve according to the present invention can be obtained with high productivity.

Since the method for manufacturing a valve according to the fifth aspect of the present invention is as described above, not only can the valve according to the present invention be obtained with high productivity, but there is no fear of deterioration of the reinforcing material. . . In addition, since the injection molding is performed in one step, no interface between the resins is generated except for the weld line, the adhesive strength between the resin and the reinforcing material is increased, and intrusion of water or the like from the interface is avoided.

[Brief description of the drawings]

FIG. 1 is a half sectional view showing an embodiment of a valve according to the present invention.

FIG. 2 is a perspective view of a reinforcement of the valve of FIG. 1;

FIG. 3 is a cross-sectional view of an injection mold used in a first step of the method of manufacturing a valve according to the fourth aspect of the present invention, showing a state in which a cavity mold is split.

FIG. 4 is a cross-sectional view of an injection mold used in the first step of the method for manufacturing a valve according to the invention of claim 4, showing a state in which a cavity mold is closed.

FIG. 5 is a cross-sectional view of an injection mold used in a second step of the method for manufacturing a valve according to the fourth aspect of the present invention, showing a state where a cavity mold is split.

FIG. 6 is a sectional view of an injection mold used in a second step of the method for manufacturing a valve according to the fourth aspect of the present invention, showing a state in which a cavity mold is closed.

FIG. 7 is a partial sectional view of an injection mold for explaining the invention described in claim 5;

FIG. 8 is a reinforcing member supporting member that can be used in the invention of FIG. 7;

FIG. 9 is a half sectional view showing another embodiment of the valve according to the present invention.

FIG. 10 is a half sectional view showing another embodiment of the valve according to the present invention.

FIG. 11 is a half sectional view showing another reinforcing material that can be used for the valve of FIG. 1;

FIG. 12 is a perspective view showing another reinforcing material that can be used for the valve of FIG. 1;

FIG. 13 is a side view showing another reinforcing material that can be used for the valve of FIG.

14 is a side view showing another reinforcing material that can be used for the valve of FIG.

FIG. 15 is a half sectional view showing a valve manufactured in Example 4.

FIG. 16 is an explanatory diagram illustrating a method of measuring a breaking water pressure value.

FIG. 17 is an explanatory diagram illustrating a method for measuring a bending bending load.

[Explanation of symbols]

1a, 1b, 1c Valve 2, 63 Valve body 21 Receptacle (portion where deformation is likely to cause poor connection) 3 Valve (ball valve) 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h Reinforcing material 57 Reinforcing material support member 6 Weld line (part likely to be damaged) 7 Cavity mold 8 Core mold (slide core) 91 First cavity 92 Second cavity 11 Molded body

Claims (5)

[Claims] A reinforcing material for reinforcing these parts is provided by a resin forming the valve body in a part which is easily damaged when a load is applied from the outside of the resin valve body or a part in which connection is likely to occur due to deformation. A valve which is embedded and integrated in a valve body so as to surround the entire surface. 2. The valve according to claim 1, wherein the reinforcing material is provided with a punching hole having a porosity of 10 to 80%. 3. A reinforcing material for reinforcing these portions is provided in a portion which is apt to be damaged when a load is applied from the outside of the resin valve body or in a portion which is liable to be deformed and cause a connection failure. Characterized in that the entire surface of the valve is embedded and integrated so as to be surrounded by the resin forming the valve body. 4. A cavity mold which comprises a plurality of molds which can be opened and closed and which forms a mold cavity corresponding to the outer surface shape of the valve to be molded when closed, and which corresponds to the inner surface shape of the valve to be molded. A core mold, a valve body forming a part of a valve, and a reinforcing material are arranged in a cavity of a cavity mold of an injection mold including a core mold, and a core mold, a valve body, A first step of forming a first cavity surrounded by a reinforcing material, forming an inner layer by injecting a molten resin into the first cavity, and obtaining a molded body; , A second cavity is formed between the molded body and the cavity mold, and an outer layer is formed by injecting a molten resin into the second cavity. And a second step of burying and integrating so as to be surrounded by the resin. 4. The method for manufacturing a valve according to claim 3, wherein: 5. A cavity mold which comprises a plurality of molds which can be opened and closed and which forms a cavity corresponding to the outer shape of the valve to be molded when closed, and which corresponds to the inner surface shape of the valve to be molded. In a cavity of a cavity mold of an injection mold including a core mold, the core mold is advanced, and a valve body forming a part of a valve and a reinforcing material are disposed, and a core mold is provided. A method of manufacturing a valve in which a cavity surrounded by a valve body and a reinforcing material is formed, and a molten resin is injected into the cavity to form a valve in which the reinforcing material is embedded and integrated so as to be surrounded by the resin. The reinforcing material is detachably supported by a reinforcing material supporting member slidably mounted on a part of the core mold, and when the core mold advances into the mold cavity, the reinforcing material is supported. The member moves forward with the core mold and strengthens Are disposed in the mold cavity, and when the molten resin is injected, the reinforcing material supporting member is retracted by the resin pressure, whereby the reinforcing material supporting member is detached from the reinforcing material. The method for manufacturing a valve according to claim 3, wherein