阅读说明：本技术 水质分析仪用多端口阀 (Multi-port valve for water quality analyzer ) 是由 前田一真 于 2019-03-04 设计创作，主要内容包括：水质分析仪用多端口阀包括：阀头,在外表面上具有用以连接配管的多个端口,并且具有连接面,所述连接面使与各个所述端口相通的流路的端部配置在同一平面内,所述阀头包含有对水质分析仪中所使用的药品具有耐腐蚀性的树脂材料；转子,具有形成有槽的平面,且以所述平面与所述连接面相向的方式配置,所述槽是用以对配置在所述连接面上的所述流路的端部间的连接状态进行切换；以及驱动机构,用以使所述转子旋转。(The multi-port valve for the water quality analyzer comprises: a valve head having a plurality of ports for connecting pipes on an outer surface thereof and a connecting surface for arranging end portions of flow paths communicating with the ports on the same plane, the valve head including a resin material having corrosion resistance to chemicals used in a water quality analyzer; a rotor having a plane surface on which grooves are formed for switching a connection state between end portions of the flow paths arranged on the connection surface, the plane surface being arranged to face the connection surface; and a drive mechanism to rotate the rotor.)

1. A multiport valve for a water quality analyzer, comprising:

a valve head having a plurality of ports for connecting pipes on an outer surface thereof and a connecting surface for arranging end portions of flow paths communicating with the ports on the same plane, the valve head including a resin material having corrosion resistance to chemicals used in a water quality analyzer;

a rotor having a plane surface on which grooves are formed for switching a connection state between end portions of the flow paths arranged on the connection surface, the plane surface being arranged to face the connection surface; and

a drive mechanism to rotate the rotor.

2. The multi-port valve for a water quality analyzer according to claim 1, wherein a stator fixed to the valve head side is interposed between a plane of the rotor on which the groove is formed and the connection surface of the valve head.

3. The multiport valve for a water quality analyzer as set forth in claim 2, wherein the rotor and the stator comprise materials having different hardness from each other.

4. The multi-port valve for a water quality analyzer according to claim 1, wherein the flat surface of the rotor formed with the groove is in contact with the connection surface of the valve head.

5. The multi-port valve for a water quality analyzer according to claim 4, wherein the rotor comprises a resin material softer than the valve head.

6. The multiport valve for a water quality analyzer according to claim 1, wherein the valve head is made of a fluororesin.

7. The multiport valve for water quality analyzers as set forth in claim 6, wherein a stator fixed to the valve head side is interposed between a plane of the rotor on which the grooves are formed and the connection surface of the valve head,

at least any one of the rotor and the stator includes a resin material.

8. The multiport valve for a water quality analyzer as set forth in claim 7, wherein the material of the rotor is a fluororesin.

9. The multiport valve for a water quality analyzer according to claim 7, wherein the material of the stator is a fluororesin.

Technical Field

The present invention relates to a multi-port valve (multi-port valve) for a water quality analyzer.

Background

In a water quality analyzer, treatments such as sample selection, reagent suction, reagent addition to a sample, sample transport to an oxidation reaction portion, and sample transport to a measurement portion are performed using a syringe pump (syringe pump). These processes are performed by switching a flow path communicating with the syringe pump by a multiport valve (see patent document 1).

In water quality analyzers, highly corrosive reagents such as strong acids or strong bases are often used. Therefore, the parts of the water quality analyzer that may come into contact with the reagent should include a material that is resistant to corrosion by the reagent. For the above reasons, the multiport valve of the water quality analyzer is configured such that the reagent does not come into contact with the metal portion.

Specifically, the multi-port valve includes a valve body (valve body), a valve head (valve head), a rotor (rotor), a stator (stator), and the like. The valve head is a metal member attached to the tip of the valve body. The valve head is provided with a plurality of recessed screw holes for fixing the pipe. The stator is mounted on the valve head, and a flow path communicated with a pipe fixed in a concave screw hole of the valve head is arranged in the stator. The rotor has a groove for communicating between the flow paths provided in the stator, and is rotated while sliding with the stator to switch the flow paths of the stator that are communicated.

[ Prior art documents ]

[ patent document ]

Patent document 1: japanese patent laid-open publication No. 2013-015387

Disclosure of Invention

[ problems to be solved by the invention ]

In a multiport valve of a water quality analyzer, a pipe is fixed in a recessed screw hole of a valve head in a state that a front end portion of the pipe is strongly pushed against a stator, and a connecting portion between a flow passage inside the stator and the pipe is sealed so that a highly corrosive reagent or the like does not contact with the valve head made of metal. With such a configuration, stress is applied to the stator pushed against the distal ends of the plurality of pipes from a plurality of directions, and particularly, if the stress is uneven, the stator may be deformed, or a ferrule (ferule) attached to the distal end of the pipe may be deformed, thereby causing liquid leakage inside the multiport valve.

If liquid leaks from the inside of the multiport valve, corrosion, rust, or the like occurs in the metal valve head, which may cause problems such as water collection failure, crystallization of reagents, and fastening of joint parts. Further, the stator may be fixed to the valve head, and in the worst case, the stator may not be replaced.

Accordingly, an object of the present invention is to prevent leakage in a multiport valve due to stress applied to a stator from multiple directions.

[ means for solving problems ]

The multi-port valve for a water quality analyzer of the present invention comprises: a valve head having a plurality of ports for connecting pipes on an outer surface thereof and a connecting surface for arranging end portions of flow paths communicating with the ports on the same plane, the valve head including a resin material having corrosion resistance to chemicals used in a water quality analyzer; a rotor having a plane surface on which grooves are formed, the grooves being arranged so as to face the connection surface, the grooves being for switching a connection state between ends of the flow paths arranged on the connection surface; and a drive mechanism to rotate the rotor.

That is, the multiport valve for a water quality analyzer according to the present invention is not configured such that the tip of the pipe is pushed against the stator, but the valve head is made of a corrosion-resistant material, and the pipe is connected to the flow path provided in the valve head. In short, the multiport valve for a water quality analyzer according to the present invention does not have a structure in which the tip of the pipe is pushed against the stator from a plurality of directions.

In the present invention, a stator fixed to the valve head side may be interposed between a flat surface of the rotor on which the groove is formed and the connection surface of the valve head.

In this case, if the rotor and the stator are made of the same material, the sliding surfaces of the rotor and the stator may be adhered to each other by friction, and the rotor and the stator may be fixed to each other. Therefore, the rotor and the stator preferably include materials having different hardness from each other. In this way, the adhesion of the rotor and the stator can be prevented. Further, since either one of the rotor and the stator is made of a material softer than the other, and the one made of the soft material is elastically deformed, the sealing property between the two is improved.

In the present invention, the stator may not be interposed between the valve head and the rotor. That is, the flat surface of the rotor formed with the groove may directly meet the attachment surface of the valve head.

In that case, the rotor may comprise a softer resin material than the valve head. In this way, the rotor is more easily worn than the valve head by the sliding between the valve head and the rotor, and thus the wear of the valve head can be suppressed.

As a material of the valve head, a fluororesin may be used. Examples of the fluororesin include Polytetrafluoroethylene (PTFE) and Polychlorotrifluoroethylene (PCTFE).

The stator fixed to the valve head side may be interposed between a flat surface of the rotor formed with the groove and the connection surface of the valve head. In this case, at least either one of the rotor and the stator may be constituted by a resin material. In this way, the resin material is easily elastically deformed, and thus the sealing property between the rotor and the stator can be improved.

In this case, the rotor may be made of fluororesin.

The stator may be made of fluororesin.

[ Effect of the invention ]

The multi-port valve for the water quality analyzer of the present invention is configured such that the valve head is made of a corrosion-resistant material, and the pipe is connected to the flow path provided in the valve head, and therefore, the multi-port valve does not have a structure in which the tip of the pipe is pushed against the stator from a plurality of directions, and thus, leakage due to such a structure does not occur.

Drawings

Fig. 1 is a sectional view showing an embodiment of a multiport valve for a water quality analyzer.

Fig. 2 is a sectional view showing another embodiment of a multiport valve for a water quality analyzer.

Fig. 3 is an image showing the state of a flow path when a valve head made of polyphenylene sulfide (PPS) is used for a long period of time.

Fig. 4 is a diagram showing a state of a flow path when a valve head made of PCTFE is used for a long period of time.

Detailed Description

Hereinafter, an embodiment of a multiport valve for a water quality analyzer will be described with reference to the drawings.

The multiport valve 1 for a water quality analyzer of an embodiment includes a valve body 2 and a valve head 4. The valve head 4 is mounted on the front end of the valve body 2. The valve head 4 has an outer surface provided with a plurality of ports 6 including recessed screw holes for connecting pipes. The port 6 communicates with a flow passage 8 provided inside the valve head 4, and an end of the flow passage 8 is disposed on a flat surface 4a of the valve head 4 forming the innermost surface of the internal space of the valve body 2. The flat surface 4a of the valve head 4 forms a connecting surface in which the end portions of the flow paths 8 communicating with the ports 6 are aligned on the same plane.

A stator 10 is attached to the flat surface 4a of the valve head 4. The stator 10 is inserted between the valve head 4 and a rotor 14 described later and slides on the rotor 10. The stator 10 has a through hole 12 at a position corresponding to an end of the flow path 8 provided on the flat surface 4 a.

The rotor 14 is held at the tip end 18a of the rotor shaft 18 inside the valve body 2. The rotor 14 has a flat surface facing the flat surface 4a of the valve head 4, and grooves 16 are provided in the flat surface to communicate between the end portions of the flow passages 8. In the rotor 14, a plane provided with the groove 16 abuts on the stator 12, and rotates while sliding on the stator 12 with the rotation of the rotor shaft 18, thereby switching between the ends of the flow paths 8 that communicate with each other.

The rotor shaft 18 is biased toward the valve head 4 by an elastic member such as a coil spring (coil spring), and thereby presses the rotor 14 to the stator 10. The rotor shaft 18 is rotated by a stepping motor 22. The rotor shaft 18 and the stepper motor 22 form a drive mechanism to rotate the rotor 14.

In the multi-port valve 1 for a water quality analyzer of the present embodiment, at least the valve head 4, the stator 10, and the rotor 14 are made of a material having corrosion resistance to a reagent that may be used in the water quality analyzer. Examples of such materials include polyphenylene sulfide (PPS), Polyetheretherketone (PEEK), Polytetrafluoroethylene (PTFE), and ceramics.

In particular, by using a fluororesin such as PTFE or PCTFE as a corrosive material, the generation of rust and the clogging of a flow path due to the melting or erosion of the material can be prevented. The inventors examined the durability of the valve head 4 when PPS is used as the material of the valve head 4 and when PCTFE is used. If the valve head 4 made of PPS is used for a long period of time, as shown in fig. 3, a flow path provided in the valve head 4 is clogged. On the other hand, even if the valve head 4 made of PCTFE is used for a long period of time, the flow path provided in the valve head 4 is not clogged as shown in fig. 4. Therefore, if a fluororesin such as PCTFE is used as the material of the stator 10 and the rotor 10 in addition to the valve head 4, the flow path can be effectively prevented from being clogged due to the melting and erosion of the material.

In particular, by forming the valve head 4 of a corrosion-resistant material as described above, a highly corrosion-resistant chemical such as a strong acid or a strong alkali can be made to flow through the flow passage 8 in the valve head 4. Therefore, it is not necessary to seal the pipe through which the chemicals flow by pushing against a member (for example, a stator) different from the valve head 4.

With the above-described structure, the sealing surface in the valve 1 is defined by the surface between the valve head 4 and the stator 10 and the surface between the stator 10 and the rotor 14, and stress is applied only in the direction perpendicular to the sealing surface. That is, the fastening force of the joint for connecting pipes acts only on the valve head 4, and no stress is applied from a direction other than the direction perpendicular to the sealing surface in the valve 1.

The stator 10 and the rotor 14 preferably include materials (e.g., ceramic, PEEK, etc.) having different hardness from each other. As a result, the member made of a soft material is elastically deformed, and the sealing property between the stator 10 and the rotor 14 is improved. In particular, since the rotor 14 is a replaceable consumable, it is more preferable to form the rotor 14 from a material (for example, PEEK) that is softer than the stator 10.

Further, as in the multi-port valve 1' for a water quality analyzer shown in fig. 2, the rotor 14 may be in direct contact with the valve head 4 without interposing a stator between the valve head 4 and the rotor 14. In this case, in order to suppress wear of the valve head 4, it is preferable to form the rotor 14 of a material softer than the valve head 4. For example, the valve head 4 may be formed of PPS and the rotor 14 may be formed of PEEK.

By adopting the configuration shown in fig. 2, the sealing surface in the valve 1 'is only the surface between the valve head 4 and the rotor 14, and the fastening force of the joint for connecting the pipes acts only on the valve head 4, so that stress is applied only in the direction perpendicular to the sealing surface in the valve 1'.

[ description of symbols ]

1. 1': multi-port valve for water quality analyzer

2: valve body

4: valve head

6: port(s)

8: flow path

10: stator

12: through hole

14: rotor

16: trough

18: rotor shaft

20: elastic member

22: a stepper motor.