Rotary valve and method for forming reinforced resin part of rotary valve

Abstract

A rotary valve and a method for forming a reinforced resin component of the rotary valve are provided, which can maintain the sealing between the rotor and the stator for a long period of time. A rotary valve includes: a stator (4); an axially rotating rotor shaft (8); and a rotor (6) held at the front end of the rotor shaft (8), in contact with the surface of the stator (4), and rotating together with the rotor shaft (8). The stator (4) and the rotor (6) have sliding surfaces that slide against each other due to the rotation of the rotor (6). Either the stator (4) or the rotor (6) is a reinforced resin component made of fiber-reinforced resin containing reinforcing fibers for increasing hardness. The reinforcing fibers exposed on the sliding surface of the reinforced resin component are oriented primarily along a direction perpendicular to the sliding surface of the reinforced resin component.

Description

Technical Field

[0001] This invention relates to a rotary valve for analytical apparatus such as a liquid chromatograph, and a method for forming a reinforced resin component of the rotary valve. Background Technology

[0002] The rotary flow path switching valve (hereinafter referred to as the rotary valve) used in liquid chromatographs needs to withstand high liquid delivery pressures ranging from tens to hundreds of megapascals. Therefore, elastic components such as helical springs are used to forcefully press the rotor against the stator to ensure a tight seal between the rotor and the stator (see Patent Document 1).

[0003] Since the rotor and stator slide under strong mutual pressure, the sliding surfaces of the rotor and stator are required to have high sealing and wear resistance. Therefore, the stator is usually made of ceramic or hard stainless steel with a DLC (diamond-like carbon) coating (see, for example, Patent Document 2), while the rotor is usually made of soft materials such as PEEK (polyetheretherketone) or polyimide.

[0004] [Existing Technical Documents]

[0005] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent No. 6773233

[0007] [Patent Document 2] US Patent No. 8438910 Specification Summary of the Invention

[0008] [Technical problems to be solved]

[0009] Environments with pressures exceeding 130 MPa applied to the rotor or stator create harsh conditions that cause plastic deformation in soft materials such as PEEK. Under these conditions, the sliding between soft and hard materials leads to rapid wear of the soft material, shortening component lifespan. Therefore, countermeasures have been implemented, such as using fiber-reinforced resins containing reinforcing fibers like carbon fiber as the soft material. However, even with these wear countermeasures, problems persist: one or both sliding surfaces of the rotor and stator will wear, and after a period of use, the seal between the rotor and stator will deteriorate, leading to leakage.

[0010] The present invention was made in view of the above-mentioned problems, and its purpose is to maintain the sealing between the rotor and the stator for a long period of time.

[0011] [Technical Solution to the Problem]

[0012] Research has revealed a problem when one component of the mutually sliding stator and rotor is made of a rigid material, while the other is made of fiber-reinforced resin. The reinforcing fibers contained in the resin cause wear on the component made of the rigid material, thus accelerating the decrease in the seal between the stator and rotor. The inventors then realized that the orientation of the reinforcing fibers in the fiber-reinforced resin on the sliding surface affects the wear of the component made of the rigid material. By making the orientation of the reinforcing fibers exposed on the sliding surface approximately perpendicular to the sliding surface, wear on the component made of the rigid material can be suppressed.

[0013] The first rotary valve of the present invention based on the above insights comprises: a stator; an axially rotating rotor shaft; and a rotor held at the front end of the rotor shaft, in contact with the stator surface and rotating together with the rotor shaft, wherein the stator and the rotor have sliding surfaces that slide against each other due to the rotation of the rotor, and either the stator or the rotor is a reinforced resin component made of a fiber-reinforced resin containing reinforcing fibers for increasing hardness, wherein the reinforcing fibers exposed on the sliding surface of the reinforced resin component are oriented primarily along a direction perpendicular to the sliding surface of the reinforced resin component.

[0014] Furthermore, when the stator is made of a hard material and the rotor is made of a soft material, the rotor is prone to wear, and the area around the rotor grooves will expand due to wear, making it easy for liquid to leak.

[0015] The second rotary valve of the present invention, which addresses the above-mentioned problems, comprises: a stator; an axially rotating rotor shaft; and a rotor held at the front end of the rotor shaft, in contact with the stator surface, and rotating together with the rotor shaft, wherein the stator is made of resin, and at least the sliding surface of the rotor with the stator is made of a material harder than the stator.

[0016] Furthermore, if the opposing surfaces of the stator and rotor are not parallel, one-sided contact will occur, resulting in the inability to achieve the designed pressure resistance performance. Alternatively, sliding under one-sided contact can lead to accelerated wear and reduced durability. To prevent these problems, the stator, rotor, and their supporting components need to be manufactured with high precision, or other components that allow the rotor to tilt and provide elastic support need to be installed, which is costly.

[0017] The third rotary valve of the present invention, which addresses the above-mentioned problems, comprises: a stator; an axially rotating rotor shaft; and a rotor held at the front end of the rotor shaft, in contact with the stator surface, and rotating together with the rotor shaft. A generally spherical portion, which is part of either the rotor or the rotor shaft, is provided between the rotor and the rotor shaft. By having the rotor and the rotor shaft in direct contact with the generally spherical portion, the sliding surface of the rotor can be tilted from a state perpendicular to the rotation axis of the rotor shaft.

[0018] Furthermore, in order to improve the sliding properties and wear resistance of the rotor and stator, when a DLC coating is applied to either the rotor or the stator (e.g., the stator), the DLC film may peel off from the substrate, causing leakage between the rotor and the stator. This problem is particularly pronounced when one of the rotor and stator is a DLC forming component with a DLC film, and the other is a soft component such as resin. This is believed to be because the soft component is forcefully pressed against the DLC forming component, causing the deformed soft component to enter the opening at the flow path end of the DLC forming component. When the two slide, the soft component entering the opening exerts a cutting force on the DLC film at the edge of the opening. Therefore, the inventors have focused on the thickness of the sliding surface of the DLC forming component from the substrate surface to the DLC film surface. In DLC coatings, it is known that the thicker the formed DLC film, the higher the wear resistance; typically, the thickness of the DLC film formed by DLC coating is about 1 to 3 μm. However, if the thickness of the DLC film increases, its residual stress also increases, making the DLC film more prone to peeling off from the substrate. Furthermore, if the thickness from the substrate surface to the DLC film surface is large, when the DLC forming component and the flexible component slide, the DLC film located at the opening edge of the DLC forming component is easily subjected to peeling stress transmitted from the flexible component entering the opening.

[0019] The inventors conducted sliding experiments with soft components using multiple DLC forming components with varying thicknesses from the substrate surface to the DLC film surface. The results confirmed that, compared to DLC forming components with a thicker thickness from the substrate surface to the DLC film surface, DLC forming components with a thinner thickness from the substrate surface to the DLC film surface were less prone to DLC film peeling and had a longer lifespan, especially when the thickness from the substrate surface to the DLC film surface was less than 0.5 μm. The fourth rotary valve of this invention is based on this insight.

[0020] That is, the fourth rotary valve of the present invention comprises: a stator; and a rotor that contacts and rotates with the surface of the stator, wherein the stator and the rotor each have a sliding surface that slides against each other due to the rotation of the rotor, and either the stator or the rotor is a DLC forming member whose sliding surface is formed of a DLC film, wherein the thickness from the substrate surface of the sliding surface side of the DLC forming member to the surface of the DLC film is 0.5 μm or less.

[0021] The method of the present invention is a method for forming either a rotor or a stator having sliding surfaces that are in direct contact and sliding with each other in the aforementioned first rotary valve into a reinforced resin component made of a fiber-reinforced resin containing reinforcing fibers for improving hardness, comprising:

[0022] In the flow step, liquid fiber-reinforced resin is flowed in one direction, which is perpendicular to the direction of the surface that will become the sliding surface when formed into the reinforced resin component.

[0023] A curing step, following the flow step, cures the fiber-reinforced resin.

[0024] The forming step involves forming the reinforced resin component using the cured fiber-reinforced resin as a substrate after the curing step, wherein the reinforced resin exposed on the sliding surface is oriented primarily along a direction perpendicular to the sliding surface.

[0025] [Invention Effects]

[0026] According to the first rotary valve of the present invention, either the stator or the rotor is a reinforced resin component made of fiber-reinforced resin containing reinforcing fibers for increasing hardness. The reinforcing fibers exposed on the sliding surface of the reinforced resin component are oriented mainly along a direction perpendicular to the sliding surface of the reinforced resin component. Therefore, wear on the sliding surfaces of the stator and rotor is reduced, and the sealing between the stator and rotor can be maintained for a long time.

[0027] According to the second rotary valve of the present invention, the stator is made of resin, while at least the sliding surface of the rotor with the stator is made of a material harder than the stator. Therefore, the expansion of the grooves of the rotor due to wear is suppressed, and the sealing between the stator and the rotor can be maintained for a long time.

[0028] According to the third rotary valve of the present invention, a generally spherical portion is provided between the rotor and the rotor shaft, which is part of either the rotor or the rotor shaft. By having the rotor and the rotor shaft in direct contact with the generally spherical portion, the sliding surface of the rotor can be tilted from a state perpendicular to the rotation axis of the rotor shaft. Therefore, unilateral contact between the stator and the rotor can be prevented, and the sealing between the stator and the rotor can be maintained for a long time.

[0029] According to the fourth rotary valve of the present invention, either the stator or the rotor is a DLC forming component whose sliding surface is formed by a DLC film. The thickness from the substrate surface to the DLC film surface on the sliding surface side of the DLC forming component is less than 0.5 μm. Therefore, the DLC film of the DLC forming component is not easily peeled off, and the long life of the DLC forming component can be achieved.

[0030] According to the method of the present invention, a reinforced resin component can be formed in which the reinforcing fibers exposed on the sliding surface are oriented primarily in a direction perpendicular to the sliding surface. Attached Figure Description

[0031] Figure 1 This is a cross-sectional view showing one embodiment of a rotary valve.

[0032] Figure 2 This is a conceptual diagram illustrating an example of a method for forming fiber-reinforced resin.

[0033] Figure 3 This is a diagram showing the orientation direction of the reinforcing fibers when a reinforcing resin component is formed in a direction parallel to the direction that will become the sliding surface, causing the fiber-reinforced resin to flow.

[0034] Figure 4 This is an image showing the state of the sliding surfaces of the stator and rotor after the reinforcing resin component, in which the reinforcing fibers exposed on the sliding surface are oriented mainly in a direction perpendicular to the sliding surface, is used as the stator.

[0035] Figure 5 This is an image showing the state of the respective sliding surfaces of the stator and rotor after the reinforcing resin component with the reinforcing fibers exposed on the sliding surface is mainly oriented along the sliding surface is used as the stator.

[0036] Figure 6 This is a diagram showing the structure of the contact area between the rotor and the rotor shaft.

[0037] Figure 7 This is a diagram showing an example of the cross-sectional structure of a DLC-formed component.

[0038] [Symbol Explanation]

[0039] 1 Rotary valve

[0040] 2 shells

[0041] 4 stators

[0042] 6 rotors

[0043] 8 rotor shafts

[0044] 10 bearings

[0045] 12 elastic components

[0046] 14 sales

[0047] 16-speed ring

[0048] 18 Piping Connections

[0049] 20 approximately spherical parts Detailed Implementation

[0050] Hereinafter, an embodiment of the rotary valve according to the present invention will be described with reference to the accompanying drawings.

[0051] like Figure 1 As shown, the rotary valve 1 includes a housing 2, a stator 4, a rotor 6, a rotor shaft 8, a bearing 10, and an elastic component 12.

[0052] The housing 2 is a generally hollow cylindrical, one-piece component with an open front end (upper end in the figure). A stator 4 is bolted to the front end of the housing 2. The stator 4 has multiple pipe connection parts 18 for connecting piping. It should be noted that only one pipe connection part 18 is shown in the figure. The pipe connection part 18 extends through a flow path to the inner space side of the housing 2 (lower end in the figure). The rotor 6 rotates while in contact with the lower end of the stator 4, switching the interconnection states between the multiple pipes connected to the stator 4.

[0053] The rotor shaft 8 is disposed within the internal space of the housing 2, with its front end (upper end in the figure) facing the stator 4. The rotor shaft 8 is driven to rotate axially by a motor (not shown in the figure). The rotor 6 is held at the front end of the rotor shaft 8 and rotates as the rotor shaft 8 rotates.

[0054] The bearing 10 is located between the outer circumferential surface of the rotor shaft 8 and the inner circumferential surface of the housing 2, supporting the rotor shaft 8 and stabilizing its rotation. In this embodiment, a retaining ring 16 is installed at the front end of the rotor shaft 8, and the bearing 10 engages with the retaining ring 16.

[0055] The elastic member 12 is compressed and positioned within the internal space of the housing 2, closer to the base end of the rotor shaft 8 than the bearing 10, to apply force to the bearing 10 towards the stator 4. By applying force to the bearing 10 towards the stator 4 through the elastic member 12, force is applied to the rotor shaft 8 towards the stator 4, pressing the rotor 6, held at the front end of the rotor shaft 8, against the stator 4. This ensures a tight seal between the stator 4 and the rotor 6. It should be noted that in this embodiment, the rotor 6 directly contacts the stator 4, but the invention is not limited to this; other components fixed to the stator 4 can also be inserted between the stator 4 and the rotor 6.

[0056] The stator 4 can be made of resin. If the stator 4 is made of resin, it can be used in applications where solvents corrosive to metals are used. The resin constituting the stator 4 can be a fiber-reinforced resin such as polyetheretherketone resin or polyimide resin containing reinforcing fibers (e.g., carbon fibers) to improve hardness. By making the stator 4 into a reinforced resin component made of fiber-reinforced resin, the hardness of the stator 4 can be increased, thereby improving the pressure resistance of the rotary valve 1.

[0057] When the stator 4 is made of resin, the sliding surface of the rotor 6 at least with respect to the stator 4 (top of the figure) can be a hard component made of a material harder than the stator 4 (e.g., ceramic, diamond-like carbon). By making the sliding surface of the rotor 6 at least with respect to the stator 4 a material harder than the stator 4, the enlargement of the grooves provided on the rotor 6 due to wear can be suppressed.

[0058] It should be noted that the present invention is not limited thereto. The rotor 6 may also be formed of fiber-reinforced resin, and at least the sliding surface of the stator 4 with the rotor 6 may be made of a material harder than the rotor 6.

[0059] When the stator 4 is a reinforced resin component made of fiber-reinforced resin, the reinforcing fibers of the stator 4 exposed on the sliding surface with the rotor 6 are mainly oriented in a direction perpendicular to the sliding surface (bottom of the figure) (vertical direction in the figure). It should be noted that when the rotor 6 is a reinforced resin component, the reinforcing fibers of the rotor 6 exposed on the sliding surface with the stator 4 are mainly oriented in a direction perpendicular to the sliding surface with the stator 4 (top of the figure).

[0060] Here, refer to Figure 2 The method for forming the reinforced resin component in this embodiment will be described. Here, injection molding will be used as an example.

[0061] like Figure 2 As shown in (A), liquid fiber-reinforced resin is injected into the interior space of the mold along a direction perpendicular to the surface that will become the sliding surface when molded into a resin-reinforced part. This flow of the fiber-reinforced resin results in the reinforcing fibers primarily oriented along the inner surface of the mold at the deepest part of the mold interior, but in areas closer to the gate, the reinforcing fibers primarily oriented along a direction perpendicular to the surface that will become the sliding surface. Then, as... Figure 2 As shown in (B), after the fiber-reinforced resin filling the interior space of the mold has cured, the substrate of the reinforced resin part is obtained by demolding. Next, as... Figure 2As shown in (C), the substrate of the reinforced resin component is processed by cutting (or slitting) to a predetermined thickness at the deepest part of the mold, thereby obtaining a reinforced resin component in which the reinforcing fibers exposed on the surface that will become the sliding surface are oriented mainly in a direction perpendicular to the surface that will become the sliding surface. This method is equally applicable to both the stator 4 and the rotor 6.

[0062] In the case of forming cylindrical reinforced resin parts by conventional injection molding, such as Figure 3 As shown, fiber-reinforced resin is typically injected from the side (parallel to the direction of the surface that will become the sliding surface after molding) into the roughly cylindrical space inside the mold that forms the substrate shape. In this case, at the location that will become the sliding surface, the reinforcing fibers will primarily oriented along the sliding surface.

[0063] Here, "the reinforcing fibers exposed on the sliding surface are mainly oriented in a direction perpendicular to the sliding surface" means that most of the reinforcing fibers exposed on the sliding surface of the fiber-reinforced resin (e.g., more than 50%) are oriented in a direction that intersects (not necessarily orthogonal) the sliding surface.

[0064] It should be noted that, Figure 2 This is an example of injection molding, but the method of the present invention is not limited to this. Reinforced resin parts can also be formed by methods such as extrusion molding, which includes a step of flowing liquid fiber-reinforced resin in a direction perpendicular to the surface that will become the sliding surface. Figure 2 In the case of injection molding to form reinforced resin parts, gate marks may sometimes remain on the sliding surface of the reinforced resin parts or on the surface parallel to the sliding surface.

[0065] Figure 4 This is an example of a stator using reinforcing fibers exposed on the sliding surface, oriented primarily in a direction perpendicular to the sliding surface. It is an image of the sliding surfaces of the stator and rotor after the stator with the reinforcing fibers exposed on the sliding surface oriented primarily in a direction perpendicular to the sliding surface has undergone 700,000 reciprocating cycles with a ceramic rotor. Figure 5 This is an example of a stator using reinforcing fibers exposed on the sliding surface, oriented primarily along the sliding surface direction. It is an image of the sliding surfaces of the stator and rotor after the stator with reinforcing fibers exposed on the sliding surface oriented primarily along the sliding surface has undergone 700,000 reciprocating cycles with a ceramic rotor.

[0066] Compare Figure 4 Microscopic images of the stator sliding surface shown and Figure 5 The microscopic image of the stator sliding surface shown is in Figure 4 In the stator sliding surface, the proportion of reinforcing fibers exposed in a dotted pattern is relatively high, while... Figure 5 In the stator sliding surface, a higher proportion of reinforcing fibers are exposed in a linear form.

[0067] Because of this difference, Figure 4 The proportion of exposed reinforcing fiber area in the stator sliding surface is less than Figure 5 The proportion of the area of ​​exposed reinforcing fibers in the stator sliding surface can be considered as... Figure 4 The stator causes more damage to the rotor than Figure 5 The stator should be small.

[0068] In fact, comparison Figure 4 The rotor sliding surface shown and Figure 5 The rotor sliding surface shown can be clearly seen to be in relation to... Figure 5 The stator slides on the rotor, compared to... Figure 4 The wear of the rotor is significantly more severe when the stator slides. Conversely, if a reinforced resin component with reinforcing fibers exposed on the sliding surface oriented primarily perpendicular to the sliding surface is used, the wear of the component sliding with the reinforced resin component (in this case, the rotor) can be suppressed compared to the case where a reinforced resin component with reinforcing fibers exposed on the sliding surface oriented primarily along the sliding surface is used.

[0069] Back Figure 1 Continuing the explanation, the rotor 6 is provided with a through hole, and the front end face of the rotor shaft 8 is provided with a hole. The pin 14, which passes through the through hole of the rotor 6, is embedded in the hole of the front end face of the rotor shaft 8, so that the rotor 6 is fixed relative to the rotor shaft 8 only in the direction of rotation.

[0070] like Figure 6 As shown, a generally spherical portion 20 protruding toward the rotor shaft 8 side is provided on the surface of rotor 6 (lower part in the figure). Rotor 6 contacts rotor shaft 8 only through the generally spherical portion 20, and rotor 6 can tilt and swing slightly (e.g., at most about 0.5°) on the front end face of rotor shaft 8 with its sliding surface (upper part in the figure) perpendicular to the rotation axis of rotor shaft 8. Thus, when rotor 6 is pressed against stator 4, stator 4 and rotor 6 can make precise surface contact without one-sided contact.

[0071] It should be noted that the approximately spherical part 20 does not necessarily have to be set on the rotor 6, but can also be set on the front end face of the rotor shaft 8.

[0072] Furthermore, either stator 4 or rotor 6 can also be as follows: Figure 7 As shown, the sliding surface of the DLC forming component is formed from a DLC film. In this case, the thickness T from the substrate surface to the DLC film surface on the sliding surface side (upper side in the figure) of the DLC forming component is less than 0.5 μm.

[0073] The inventors developed a stator and a rotor made of fiber-reinforced resin (polyetheretherketone) with DLC films of thicknesses of 2μm, 1μm, 0.5μm, and 0.1μm directly formed on the surface of a stainless steel substrate. These were used as the stator and rotor of an autosampler's injection valve (a six-way two-position valve). Water was used as the solvent, and the system was subjected to a continuous switching durability test at an infusion pressure of 100MPa. In the durability test, the injection valve using the stator with the 2μm thick DLC film leaked after approximately 10,000 switching cycles due to DLC film peeling; the injection valve using the stator with the 1μm thick DLC film leaked after approximately 15,000 switching cycles due to DLC film peeling. On the other hand, even after more than 20,000 switching operations, no leakage occurred between the stator and rotor when using a sample valve with a stator having a DLC film with a thickness of 0.5 μm; and even after more than 150,000 switching operations, no leakage occurred between the stator and rotor when using a sample valve with a stator having a DLC film with a thickness of 0.1 μm. These experimental results demonstrate that by setting the thickness from the substrate surface of the DLC forming component to the DLC film surface to less than 0.5 μm, the durability of the seal between the stator and rotor can be significantly improved.

[0074] It should be noted that in the above experiment, the DLC film was formed in direct contact with the substrate surface. However, the present invention is not limited to this, and an adhesive layer or the like can also be inserted between the substrate surface and the DLC film. In this case, it is important that the thickness from the substrate surface to the DLC film surface is less than 0.5 μm. Even if the DLC film thickness is less than 0.5 μm, if the thickness from the substrate surface to the DLC film surface exceeds 0.5 μm due to the presence of an adhesive layer or the like, the step from the DLC film opening edge of the DLC forming component to the substrate opening edge will become larger. As a result, when the DLC forming component (the stator in the above experiment) and the soft component (the rotor in the above experiment) slide, the stress in the peeling direction applied to the DLC film by the soft component entering the DLC film opening will become stronger, and the DLC film will easily peel off from the substrate. Conversely, even if there is an adhesive layer between the substrate and the DLC film, as long as the thickness from the substrate surface to the DLC film surface is controlled to be less than 0.5 μm, the stress in the peeling direction on the DLC film when the DLC forming parts and soft parts slide can be reduced, making the DLC film less likely to peel off from the substrate.

[0075] Furthermore, in the above experiment, the stator was a DLC-formed component and the rotor was a soft component, but the rotor could also be a DLC-formed component.

[0076] Patent Document 2 (US Patent No. 8,438,910) discloses a DLC forming component with a DLC film forming thickness in the range of 0.2 μm to 3 μm. However, the DLC forming component disclosed here incorporates an adhesion-promoting layer with a thickness in the range of 1 μm to 5 μm between the substrate and the DLC film. That is, the thickness of the DLC forming component disclosed in Patent Document 2 from the substrate surface to the DLC film surface is 1.2 μm or more. With this structure, the stress on the DLC film in the peeling direction is relatively large when the DLC forming component and the soft component slide, making it impossible to achieve the durability of the stator-rotor seal provided by the present invention.

[0077] The embodiments described above are merely examples of one implementation of the rotary valve and method according to the present invention. The implementation of the rotary valve and method according to the present invention is as follows.

[0078] The first embodiment of the rotary valve of the present invention,

[0079] Features: stator;

[0080] A rotor shaft that rotates axially;

[0081] And a rotor that is held at the front end of the rotor shaft, in contact with the stator surface, and rotates together with the rotor shaft.

[0082] The stator and the rotor have sliding surfaces that slide against each other due to the rotation of the rotor.

[0083] Either the stator or the rotor is a reinforced resin component made of fiber-reinforced resin containing reinforcing fibers for increasing hardness.

[0084] The reinforcing fibers exposed on the sliding surface of the reinforcing resin component are oriented primarily along a direction perpendicular to the sliding surface of the reinforcing resin component.

[0085] In the first aspect of the first embodiment described above, the reinforced resin component has injection molding gate marks on the sliding surface or on a surface parallel to the sliding surface.

[0086] In the second aspect of the first embodiment described above, the reinforced resin component is the stator. By making the stator into a reinforced resin component made of fiber-reinforced resin, the stator can be made resistant to agents that corrode metals. This second aspect can be combined with the first aspect described above.

[0087] In the second aspect described above, the sliding surface of the rotor can also be made of a non-metallic material that is harder than that of the stator. This can suppress the enlargement of rotor grooves due to wear.

[0088] In the above case, the stator may also have multiple piping connections for connecting to piping. Thus, the stator with multiple piping connections is made of fiber-reinforced resin, while the rotor is made of a non-metallic material that is harder than the stator, thereby enabling a high-pressure resistant rotary valve to be used while allowing the application of metal-corroding agents.

[0089] In the third aspect of the first embodiment described above, a generally spherical portion, which is part of either the rotor or the rotor shaft, is provided between the rotor and the rotor shaft. The rotor and the rotor shaft are in direct contact with this generally spherical portion, allowing the sliding surface of the rotor to tilt from a state perpendicular to the rotation axis of the rotor shaft. Therefore, when the rotor is pressed against the stator, the sliding surface of the rotor can follow the sliding surface of the stator and become parallel, allowing the rotor and stator to slide without unilateral contact. This third aspect can be combined with the first and / or second aspects described above.

[0090] In the third aspect described above, the generally spherical portion may also be provided as a protrusion on the surface of the rotor shaft. Although a generally spherical protrusion may also be provided on the rotor shaft, providing such a protrusion on the rotor makes the rotor less prone to breakage.

[0091] In the fourth aspect of the first embodiment described above, the other of the stator and the rotor is a DLC forming member whose sliding surface is formed of a diamond-like carbon film, and the thickness of the substrate surface on the sliding surface side of the DLC forming member to the surface of the diamond-like carbon film is less than 0.5 μm. This fourth aspect can be combined with the first, second, and / or third aspects described above.

[0092] In the fourth aspect above, the diamond-like carbon film of the DLC forming component can also be in direct contact with the substrate.

[0093] A second embodiment of the rotary valve of the present invention,

[0094] Features: stator;

[0095] A rotor shaft that rotates axially;

[0096] And a rotor that is held at the front end of the rotor shaft, in contact with the stator surface, and rotates together with the rotor shaft.

[0097] The stator is made of resin, and at least the sliding surface of the rotor that slides with the stator is formed of a material harder than the stator.

[0098] In the first aspect of the second embodiment described above, the resin constituting the stator is a fiber-reinforced resin containing reinforcing fibers for increasing hardness. By making the stator from fiber-reinforced resin, the hardness of the stator is increased dramatically compared to the case where the stator is made from resin, thus improving the pressure resistance of the rotary valve.

[0099] In a second aspect of the second embodiment described above, the stator has a plurality of piping connection portions for connecting piping.

[0100] In a third aspect of the second embodiment described above, the sliding surface of the rotor is formed of a diamond-like carbon film, and the thickness from the substrate surface on the sliding surface side of the rotor to the surface of the diamond-like carbon film is less than 0.5 μm. This third aspect can be combined with the first and / or second aspects described above.

[0101] Furthermore, in the third aspect described above, the diamond-like carbon film of the rotor can also be in direct contact with the substrate.

[0102] A third embodiment of the rotary valve of the present invention,

[0103] Features: stator;

[0104] A rotor shaft that rotates axially;

[0105] And a rotor that is held at the front end of the rotor shaft, in contact with the stator surface, and rotates together with the rotor shaft.

[0106] A generally spherical portion, which is part of either the rotor or the rotor shaft, is provided between the rotor and the rotor shaft. The rotor and the rotor shaft are in direct contact with the generally spherical portion, allowing the sliding surface of the rotor to tilt from a state perpendicular to the rotation axis of the rotor shaft.

[0107] In the third embodiment described above, the generally spherical portion may also be provided as a protrusion on the surface of the rotor shaft. Although a generally spherical protrusion may also be provided on the rotor shaft, providing such a protrusion on the rotor makes the rotor less prone to breakage.

[0108] A fourth embodiment of the rotary valve of the present invention,

[0109] Features: stator;

[0110] And the rotor that contacts and rotates with the stator surface,

[0111] The stator and the rotor each have sliding surfaces that slide against each other due to the rotation of the rotor.

[0112] Either the stator or the rotor is a DLC-formed component with a sliding surface made of diamond-like carbon film.

[0113] The thickness from the substrate surface on the sliding side of the DLC forming component to the surface of the diamond-like carbon film is less than 0.5 μm.

[0114] In the fourth embodiment described above, the diamond-like carbon film of the DLC forming component can also be in direct contact with the substrate. This second aspect can be combined with the first aspect described above.

[0115] One embodiment of the method of the present invention is a method for forming either a rotor or a stator having sliding surfaces that are in direct contact and slide against each other in a rotary valve into a reinforced resin component made of a fiber-reinforced resin containing reinforcing fibers for increasing hardness, comprising:

[0116] In the flow step, liquid fiber-reinforced resin is flowed in one direction, which is perpendicular to the direction of the surface that will become the sliding surface when formed into the reinforced resin component.

[0117] A curing step, following the flow step, cures the fiber-reinforced resin.

[0118] The forming step involves forming the reinforced resin component using the cured fiber-reinforced resin as a substrate after the curing step, wherein the reinforced resin exposed on the sliding surface is oriented primarily along a direction perpendicular to the sliding surface.

Claims

1. A rotary valve comprising: stator; Axially rotating rotor shaft; and A rotor that is held at the front end of the rotor shaft, in contact with the stator surface, and rotates together with the rotor shaft. The stator and the rotor have sliding surfaces that slide against each other due to the rotation of the rotor. Either the stator or the rotor is a reinforced resin component made of fiber-reinforced resin containing reinforcing fibers for increasing hardness. The reinforcing fibers exposed on the sliding surface of the reinforcing resin component are oriented in a direction perpendicular to the sliding surface of the reinforcing resin component.

2. The rotary valve according to claim 1, wherein, The reinforced resin component has injection molding gate marks on the sliding surface or on a surface parallel to the sliding surface.

3. The rotary valve according to claim 1, wherein, The reinforced resin component is the stator.

4. The rotary valve according to claim 3, wherein, The sliding surface of the rotor is made of a non-metallic material that is harder than that of the stator.

5. The rotary valve according to claim 4, wherein, The stator has multiple piping connection parts for connecting piping.

6. The rotary valve according to claim 1, wherein, A spherical portion, which is part of either the rotor or the rotor shaft, is provided between the rotor and the rotor shaft. The rotor and the rotor shaft are in direct contact with the spherical portion, allowing the sliding surface of the rotor to tilt from a state perpendicular to the rotation axis of the rotor shaft.

7. The rotary valve according to claim 6, wherein, The spherical portion is provided as a protrusion on the surface of the rotor shaft side of the rotor.

8. The rotary valve according to claim 1, wherein, The other of the stator and the rotor is a diamond-like carbon forming component whose sliding surface is formed of a diamond-like carbon film. The thickness from the substrate surface on the sliding side of the diamond-like carbon forming component to the surface of the diamond-like carbon film is less than 0.5 μm.

9. The rotary valve according to claim 8, wherein, The diamond-like carbon film of the diamond-like carbon forming component is in direct contact with the substrate.

10. A rotary valve comprising: stator; Axially rotating rotor shaft; and A rotor that is held at the front end of the rotor shaft, in contact with the stator surface, and rotates together with the rotor shaft. The stator is made of resin, and at least the sliding surface of the rotor that slides with the stator is formed of a material harder than the stator.

11. The rotary valve according to claim 10, wherein, The resin constituting the stator is a fiber-reinforced resin containing reinforcing fibers to improve hardness.

12. The rotary valve according to claim 10, wherein, The stator has multiple piping connection parts for connecting piping.

13. The rotary valve according to claim 10, wherein, The sliding surface of the rotor is formed of a diamond-like carbon film. The thickness from the substrate surface on the sliding side of the rotor to the surface of the diamond-like carbon film is less than 0.5 μm.

14. The rotary valve according to claim 13, wherein, The diamond-like carbon film of the rotor is in direct contact with the substrate.

15. A rotary valve comprising: stator; Axially rotating rotor shaft; and A rotor that is held at the front end of the rotor shaft, in contact with the stator surface, and rotates together with the rotor shaft. A spherical portion, which is part of either the rotor or the rotor shaft, is provided between the rotor and the rotor shaft. The rotor and the rotor shaft are in direct contact with the spherical portion, allowing the sliding surface of the rotor to tilt from a state perpendicular to the rotation axis of the rotor shaft.

16. The rotary valve according to claim 15, wherein, The spherical portion is provided as a protrusion on the surface of the rotor shaft side of the rotor.

17. A rotary valve comprising: Stator; and The rotor that contacts and rotates with the stator surface The stator and the rotor each have sliding surfaces that slide against each other due to the rotation of the rotor. Either the stator or the rotor is a diamond-like carbon forming component whose sliding surface is formed of a diamond-like carbon film. The thickness from the substrate surface on the sliding side of the diamond-like carbon forming component to the surface of the diamond-like carbon film is less than 0.5 μm.

18. The rotary valve according to claim 17, wherein, The diamond-like carbon film of the diamond-like carbon forming component is in direct contact with the substrate.

19. A method for forming either a rotor or a stator having sliding surfaces that are in direct contact and slide against each other in a rotary valve into a reinforced resin component made of a fiber-reinforced resin containing reinforcing fibers for increasing hardness, comprising: In the flow step, liquid fiber-reinforced resin is flowed in one direction, which is perpendicular to the direction of the surface that will become the sliding surface when formed into the reinforced resin component. A curing step, which, after the flow step, cures the fiber-reinforced resin; The forming step involves forming the reinforced resin component using the cured fiber-reinforced resin as a substrate after the curing step, wherein the reinforced resin exposed on the sliding surface is oriented in a direction perpendicular to the sliding surface.

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