JPH0751957B2 - Magnet pump - Google Patents

Description

TECHNICAL FIELD The present invention relates to a magnet pump in which a permanent magnet is embedded in a rotor or an impeller and the impeller is rotated by the action of a magnetic field from the outside. The present invention relates to a magnet pump suitable for handling a fluid having a strong action.

[Conventional technology]

Generally, when a fluid having strong toxicity such as strong acid or strong alkali is transferred, a magnet pump having no shaft sealing portion is used in order to prevent the fluid to be handled from leaking to the outside. This magnet pump is one in which a permanent magnet is embedded on the impeller side (rotation side) to rotate the impeller, and the impeller is rotated by a magnetic force from the outside. This permanent magnet is hermetically sealed with resin or metal, because direct contact with it often causes corrosion.

FIG. 6 is a partial vertical sectional view of a conventional magnet pump. In the figure, reference numeral 1 is a casing, and this casing 1 is composed of a suction casing 5 having a suction port 2 and a discharge port 3 and a back casing 6, and a pump for rotatably accommodating an impeller 7 in the casing 1. A chamber 4 is formed. The impeller 7 has a blade 17, a permanent magnet 8 and a main shaft 24 integrally fixed to each other, and both ends of the main shaft 24 are freely rotatable by a bearing 9 fixed to the suction casing 5 and a bearing 15 fixed to the rear casing 6. Is supported by. The permanent magnet 21 that gives rotation to the impeller is annularly fixed along the inner circumference of the magnet yoke 20 that is fastened to the drive shaft 19 of the motor 25, and the impeller 7 is rotated by the bias of the motor 25.
The fluid to be transferred flows in through the suction port 2, is pressurized by the blades 17, and flows out through the discharge port 3. In this conventional example, the liquid contact portion of the pump, that is, the casing 1, the impeller 2, and the bearings 9 and 15 are made of resin or ceramic in order to impart corrosion resistance.

FIG. 7 is a vertical cross-sectional view showing another conventional example. The conventional example (FIG. 6) adopts a radial gap type magnet joint, whereas an axial gap type magnet joint is adopted. It is an example of a magnet pump. In the figure, a casing 1 is composed of a front casing 26 and a rear casing 27, the front casing 26 is provided with a suction port 2 and a discharge port 3, and a pump for housing the impeller 7 by the front casing 26 and the rear casing 27. A chamber 4 is formed.
An annular permanent magnet 8 and a magnet yoke 23 are embedded in the impeller 7, a disc-shaped rotating side bearing 10 is fixed to the suction side of the impeller 7, and a quill-type bearing is also provided on the back side of the impeller 7.
16 is fixed. On the other hand, fixed side bearings 9 and 15 are fixed to the inner surface of the casing 1 corresponding to the bearings 10 and 16. An annular permanent magnet 21 is fixed to a disk-shaped magnet yoke 20 fixed to a drive shaft 19 of a motor (not shown), and the impeller 7 of the pump rotates in the pump chamber 4 by the bias of the motor.

[Problems to be Solved by the Invention]

In the above-mentioned conventional magnet pump, the parts that come into contact with the fluid to be transferred are mainly the impeller 7 and the inner surface of the casing 1 and the bearings. For these wetted parts, materials that do not easily react or dissolve with the transferred fluid are selected. There must be. Generally, organic polymer materials (PFA, PTFE, PPS,
Nylon, etc.), ceramics (alumina, silicon carbide, zirconia, etc.), metallic materials such as stainless steel, etc. are selected. For example, when the fluid is a strong acid, liquid such as alkali, the metallic material is corroded. Therefore, organic polymer materials and ceramics are most commonly used. Since ceramic is difficult to form a complicated shape, it is often applied only to the bearing portion, and the impeller 7 and the casing 1 are often made of an organic polymer material. But,
Since the organic polymer material has a property of allowing a gas or a liquid to pass therethrough, it is difficult to protect the metal members such as the permanent magnet 8 and the magnet yoke 23 embedded in the impeller. That is, even if the permanent magnet 8 and the magnet yoke 23 are embedded with an organic polymer material as in the above-mentioned conventional example, when the impeller is placed in a chemical such as nitric acid, hydrochloric acid, or hydrofluoric acid, However, these chemical components penetrate the organic polymer material layer and reach the surfaces of the permanent magnet 8 and the magnet yoke 23 to corrode these materials. The period until the metal material buried in the impeller 2 is corroded depends on the type of chemical
It depends on factors such as temperature / concentration / pressure, organic polymer material type / density / thickness, etc., but in any case, the metal member embedded in the impeller 7 (permanent magnet 8, magnet) in the fluid to be transferred. If the yoke 23) is essentially corroded by the chemical components in the fluid, corrosion will occur after a predetermined period of time. On the other hand, when the casing 1 is made of an organic polymer material, the chemical component that has permeated from the inside to the outside is diffused to the outside air and diluted, so that the pump is hardly adversely affected. However, in the impeller 7 that is completely surrounded by the fluid that is transferred, the chemical component that has permeated the organic polymer material layer toward the inside reacts with the permanent magnet and the magnet yoke, and as a result, the pump. Its function as
There is a problem that the corroded metal component is released into the fluid to be transferred, or the organic polymer material layer burying these metal members is destroyed and the pump itself is damaged, so that it does not function at all.

The present invention is a magnet pump in which a permanent magnet on the impeller side is embedded with an organic polymer material, in which a chemical component that permeates the organic polymer material layer is effectively blocked, and a permanent magnet or a magnet yoke is protected. The purpose is to provide a magnet pump that delays or blocks the arrival of the pump and significantly extends the service life of the pump. Furthermore, chemicals (liquid) with high purity are separated by a component derived from a permanent magnet or a magnet yoke. An object of the present invention is to provide a magnet pump suitable for transfer without being contaminated.

[Means for Solving the Problems]

In order to achieve the above object, the present invention is a magnet pump in which a permanent magnet coated with an organic polymer material is integrally provided in an impeller, and the permanent magnet is housed in an inorganic container made of glass or ceramic, A second aspect of the present invention is a magnet pump characterized in that the outside thereof is coated with an organic polymer material, which is mainly for protecting the inorganic container from damage in the specific invention, In a magnet pump in which an impeller is integrally provided with a permanent magnet coated with an organic polymer material, the permanent magnet is housed in an inorganic container made of glass or ceramic, and the outside is coated with an organic polymer material. A magnet pump characterized in that a cushioning material made of an organic polymer material is interposed between the permanent magnet and the container. A.

A third aspect of the invention is characterized in that the inorganic container is made of borosilicate glass or quartz and the joint portion of the container is welded. The fourth aspect of the invention is that the inorganic container is formed by thermal CVD. The fifth invention is characterized in that the permanent magnet is entirely covered with the buffer material.

[Work]

Since the present invention is configured as described above, the permanent magnet coated with the organic polymer material on the impeller side placed in the fluid to be transferred has a structure in which the organic polymer material layer has a chemical component in the fluid. Even if it permeates, the permeation is blocked by the inorganic container made of glass or ceramic having a dense structure, or the permeation amount is remarkably reduced.

In the second aspect of the invention, since the cushioning material made of an organic polymer material is interposed between the permanent magnet and the inorganic container made of glass or ceramic, the permanent magnet made of a hard material and the inorganic material are made of inorganic material. Local contact between the container and the container is avoided.

Further, in the third aspect of the invention, since the container made of inorganic material is made of borosilicate glass or quartz and the joint portion of the container is welded, the material itself forming the container is completely protected unless it is attacked by chemicals. The magnet is protected.

Further, in the fourth aspect of the invention, since the container is made of a silicon carbide thin film formed by CVD,
In the normal operating temperature range of magnets (200 ° C or less), there are no chemicals that corrode the container, so it can be widely used.

Furthermore, in the fifth aspect of the invention, since the entire permanent magnet is covered with the cushioning material, it is possible to prevent the inorganic container from being destroyed by a mechanical shock, and to prevent the inorganic container from being damaged by the gap. The chemical components penetrating inside are effectively reduced.

〔Example〕

 Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a magnet pump of the present invention, in which a casing 1 of the pump comprises a suction casing 5 having a fluid suction port 2 and a back casing 6 having a pressurized fluid discharge port 3, The suction casing 5 and the back casing 6 form a pump chamber 4 for accommodating the impeller 7, and the impeller 7 and the suction casing 5 are fixed with a rotating side bearing 10 and a fixed side bearing 9, respectively. 4 and the suction port 2 are communicated with each other by an inflow path 28. The materials of these parts constituting the casing 1 must have corrosion resistance to the fluid to be transferred depending on the application of the pump, but at least the suction casing 5 placed in a magnetic field of high magnetic flux density is made of a non-magnetic material. Is desirable.

The impeller 7 rotatably housed in the pump chamber 4 has a suction casing 5 of a magnet yoke 23 formed in an annular shape.
The ring-shaped permanent magnet 8 is bonded to the surface on the side of, and the permanent magnet 8 and the magnet yoke 23, which are metallic members, are housed in a quartz container 29 made of an inorganic material. The organic polymer material is covered with a molecular material, such as nylon or fluorine resin. In this embodiment, since the organic polymer material that covers the container 29 is the same material as the member that constitutes the blade 17 that functions as an impeller, the lid 7b and the case 7c in which the blade 17 and the main plate 31 are formed in advance are joined together. Bonded by welding at face 30. On the inner surface of the suction casing 5, that is, on the portion facing the pump chamber 4, a fixed-side bearing 9 having a spherical concave surface facing the impeller 7 is screwed, and this and the rotary shaft core 18 of the impeller 7 are inserted.
In the portion of the impeller 7 facing each other with respect to the direction of, the rotating side bearing 10 with the convex surface corresponding to the concave surface of the fixed side bearing 9 facing the concave surface is screwed in, and the bearing 9 and the bearing 10 slide. The rubbing supports the thrust load in the direction of the rotary shaft core 18 and the radial load in the direction perpendicular to the rotary shaft core 18. The bearings 9 and 10 are each made of a silicon carbide thin film CV with a thin film of silicon carbide on the surface of the silicon carbide sintered body.
Convex surfaces that are deposited by D and rub against each other,
A groove for generating dynamic pressure is formed on either one of the concave surfaces.

Drive magnetic force mechanism 32 that is a means for transmitting a rotational force to the impeller 7
Is a ring-shaped magnet yoke 33 to which a ring-shaped permanent magnet 34 is bonded, and is rotatably supported by a ball bearing 35. The motor unit 11 for rotating the driving magnetic force mechanism 32 has a flat iron core 12 fixed to a motor cover 36, a coil 14 wound around the iron core 12, and a rotor 37.
Is composed of a magnet yoke 38 and a permanent magnet 39 fixed to the driving magnetic force mechanism 32 so as to face the protrusions 13 of the iron core 12, and the rotor 37 is rotated by energization of the coil 14 from a power supply unit (not shown), and the rotor is rotated. The drive magnetic force mechanism 32 fixed integrally with 37 rotates. The impeller 27 rotates in synchronism with the rotation of the drive magnetic force mechanism 32, sucks the fluid from the suction port 2, further increases the pressure, and transfers the fluid from the discharge port 3 to the downstream side.

FIG. 2 is a partially enlarged view of the impeller 7 of FIG. 1 and shows a detailed structure of the impeller 7 of the magnet pump of the present invention. The permanent magnet 8 and the magnet yoke 23, which are metal members, are sealed in an inorganic quartz container 29. The container 29 is formed by laser welding an upper lid 29b and a lower lid 29c at a joint 29d. Therefore, it has a structure capable of blocking the intrusion of liquid from the outside into the metal member. In addition,
The position 29d where the container 29 is joined by welding or fusion generally requires a high temperature, which may deteriorate the properties of the permanent magnet 8. Therefore, it is desirable to set it at a position away from the permanent magnet 8. In the figure, the magnet yoke
It is done on the side of 23. Furthermore, the container 2 indicated by a broken line
9. The organic polymer material lid 7b is a protrusion for transmitting the rotational torque of the magnet yoke 23.

In the present invention, suitable materials for the inorganic container 29 made of glass or ceramics include borosilicate glass, natural quartz, and synthetic quartz as the glass, and as the ceramic, a silicon carbide sintered body, a silicon carbide thin film, Materials such as alumina can be used, but they are appropriately selected depending on the type of liquid to be transferred. For example, in the case of transferring a hydrofluoric acid-based chemical containing extremely few impurities, it is preferable to use a container formed of a silicon carbide thin film formed by CVD,
Further, when transferring sulfuric acid, hydrochloric acid, nitric acid or the like having significantly less impurities, a container made of high-purity synthetic quartz should be used. It is possible to completely enclose the permanent magnet 8 and the magnet yoke 23 in the container 29 as shown in FIG. 2 using a material such as quartz or glass that can be fused and welded. When the container is formed of a material that does not melt in the normal temperature and pressure region, it is preferable to do as shown in FIG.

FIG. 3 shows the impeller 7 of the magnet pump shown in FIG.
In another embodiment of the present invention, a silicon carbide thin film formed by thermal CVD is used as an inorganic container. In the figure, 31 is a main plate, 17 is a wing, 8 is a permanent magnet, and 23 is a magnet yoke. The structure is the same as that in FIG. 2, but since the inorganic container 29 cannot be welded to each other, the upper lid 29b and the A permeation of a corrosive component is reduced by interposing a sealing material 40 such as a fluorine resin at a joint with the lid 29c.

Next, a second invention of the present invention will be described with reference to the drawings. In the second aspect of the present invention, when the permanent magnet and the inorganic container are locally in contact with each other to transmit the rotational torque, the inorganic container is easily damaged. The present invention has been made to prevent the damage by interposing a shock absorbing material, and FIG. 4 is an impeller in which the second invention is applied to the impeller 7 of the magnet pump shown in FIG. 7 is a partially enlarged view of FIG.

In the figure, a buffer made of an organic polymer material such as fluorine resin, nylon, polyethylene, or silicon rubber is provided between a metal member made of the permanent magnet 8 and the magnet yoke 23 and a container 29 made of quartz which is an inorganic material. The material 41 is interposed. Like the container 29, the cushioning material 41 covers and seals the entire permanent magnet 8 and the magnet yoke 23. However, as long as the container 29 is kept airtight, the cushioning material 41 is
41's airtightness isn't necessary originally.

FIG. 5 shows another embodiment, in which the present invention is applied to the impeller 7 of FIG. In the figure, as compared with the impeller 7 of FIG.
The difference is that a buffer material 41 made of an organic polymer material is also interposed between the same and 23. Since the container 29 is a silicon carbide thin film container that cannot be welded, a slight penetration from the sealing material 40 cannot be prevented. Therefore, the cushioning material 41 covers the permanent magnet 8 and the magnet yoke 23 as a whole, and Not only does it absorb mechanical shock, but it also has the function of reducing the penetration of chemicals even when they have penetrated.

In all of the above-described embodiments of the present invention, the permanent magnet and the magnet yoke are integrally fixed to the impeller side of the magnet pump, but it goes without saying that the magnet yoke can be omitted if necessary. Yes.

Further, although the axial gap type magnet pump is used in the description of the embodiment, the present invention can be applied to the radial gap type magnet pump shown as a conventional example in FIG.

〔The invention's effect〕

As described above, the magnet pump of the present invention is a magnet pump in which a permanent magnet covered with an organic polymer material is integrally provided in an impeller, and the permanent magnet is housed in an inorganic container made of glass or ceramic. The magnet pump having the outside covered with an organic polymer material has the following effects.

(A) When the chemical component of the fluid to be transferred permeates the organic polymer material layer of the impeller and penetrates into the interior, the permanent magnet is protected by the inorganic container, so the chemical that reaches the permanent magnet or the magnet yoke. Is significantly reduced,
Or, because it is completely shut off, the life of the pump is greatly improved.

(B) When chemicals containing a small amount of impurities are transferred, particularly when chemicals used in semiconductor manufacturing processes are transferred, the elution of impurities from the pump poses a problem, and even in such cases, the life of the pump Is not only long
Impurities resulting from corrosion of metal members such as permanent magnets and magnet yokes are not released into the liquid to be transferred.

Further, in the second aspect of the present invention, a buffer material of an organic polymer material is interposed between the container and the permanent magnet in order to protect the inorganic container made of glass or ceramic that prevents permeation of chemical components. (C) Since the local contact between the highly brittle inorganic container and the permanent magnet is mitigated, the possibility that the inorganic container is mechanically damaged is significantly reduced. The effect of (b) is achieved more reliably.

In the third aspect of the present invention, since the container is made of a vitreous material such as quartz or borosilicate glass, the permanent magnet can be sealed by fusion or welding. Complete protection of the magnet can be achieved as long as the material of which the container is made is not attacked by the chemical.

Further, in the fourth aspect of the present invention, the container is made of a silicon carbide thin film formed by CVD, so that (e) the container is corroded in a normal magnet operating temperature range (200 degrees Celsius or less). There is no chemical to be used, and a magnet pump that can be applied to a wide range of applications can be constructed.

Furthermore, in the fifth aspect of the present invention, by covering the permanent magnet with a buffer material of an organic polymer material interposed between the inorganic container and the permanent magnet, (f) the inorganic container is mechanical It is possible to prevent destruction due to impact, and it is possible to effectively reduce the chemical components that permeate into the interior of the inorganic container through the gap, and it is possible to provide a more reliable magnet pump.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, and FIG.
FIG. 3 is a partial cross-sectional view of the impeller shown in FIG. 3, FIG. 3 is a partial cross-sectional view of the impeller showing another embodiment, FIG. 4 is a partial cross-sectional view of the impeller showing the second invention, and FIG. FIG. 6 and FIG. 7 are vertical cross-sectional views showing different conventional examples. 1 ... Casing, 2 ... Suction port, 3 ... Discharge port, 4 ...
… Pump chamber, 5 …… Suction casing, 6 …… Rear casing, 7 …… Impeller, 7b …… Lid, 7c …… Case, 8 ……
Permanent magnet, 9 ... Fixed bearing, 10 ... Rotary bearing, 11 ...
… Motor part, 12 …… Iron core, 13 …… Protrusion, 14 …… Coil, 17 …… Wing, 18 …… Shaft core, 23 …… Magnet yoke,
28 …… inflow path, 29 …… container, 30 …… joining surface, 31 …… main plate, 32 …… driving magnetic force mechanism, 33 …… magnet yoke, 34
...... Permanent magnet, 35 …… Ball bearing, 36 …… Motor cover, 37 …… Rotor, 38 …… Magnet yoke, 39
…… Permanent magnet, 40 …… Sealant.

Claims (5)

[Claims] 1. A magnet pump in which an impeller is integrally provided with a permanent magnet coated with an organic polymer material,
A magnet pump characterized in that the permanent magnet is housed in an inorganic container made of glass or ceramic, and the outside is covered with an organic polymer material. 2. A magnet pump in which an impeller is integrally provided with a permanent magnet coated with an organic polymer material,
The permanent magnet is housed in an inorganic container made of glass or ceramic, the outside is covered with an organic polymer material, and a cushioning material made of an organic polymer material is interposed between the permanent magnet and the container. Magnet pump characterized by. 3. The magnet pump according to claim 1, wherein the inorganic container is made of borosilicate glass or quartz, and the joint portion of the container is welded. 4. The magnet pump according to claim 1, wherein the inorganic container is silicon carbide formed by thermal CVD. 5. The magnet pump according to claim 1, wherein a cushioning material covers the entire permanent magnet.