WO2014155925A1

WO2014155925A1 - Pump

Info

Publication number: WO2014155925A1
Application number: PCT/JP2014/000544
Authority: WO
Inventors: 哲也福田; 植田　英稔; 日下部　毅
Original assignee: パナソニック株式会社
Priority date: 2013-03-29
Filing date: 2014-02-03
Publication date: 2014-10-02
Also published as: JP2014194189A; EP2980415B1; EP2980415A4; EP2980415A1

Abstract

A pump (1) is provided with : a casing (30) which forms the outer shell of a suction flow passage (35a), of a pump chamber (131) which connects to the suction flow passage (35a), and of a discharge flow passage (36a) which connects to the pump chamber (131); and a volute section (130) which includes a volute flow passage connecting to both the suction flow passage (35a) and the discharge flow passage (36a) and which is formed in the pump chamber (131) as a part independent of the casing (30).

Description

pump

The present invention relates to a pump that discharges a liquid whose pressure has been increased by drawing a liquid and applying a pressure to the drawn liquid.

BACKGROUND Conventionally, pumps used to increase the pressure of a liquid are known. Conventional pumps include a casing having a liquid inlet and outlet. The conventional casing has on its inner side a volute formed integrally with the part constituting the shell of the pump. That is, the casing and the volute portion are formed as an integral structure formed by integral molding.

Also, the conventional pump is a component formed independently of volute, and one end is supported by the shaft support fixed to the peripheral edge of the end of the suction port described above, and the shaft support And a rotation center shaft. In addition, conventional pumps include an impeller mounted on a rotor that rotates about a center of rotation shaft. Such a pump is disclosed, for example, in Patent Document 1.

In the pump disclosed in Patent Document 1, each of the shaft support and the casing is formed as an independent and separate part. Therefore, even if the shaft support having the same structure is provided for each of a plurality of types of pumps, a pump having the required performance can be manufactured by varying the diameter of the suction port of the casing.

According to the above-mentioned conventional pump, it is possible to use a shaft support having the same structure for a plurality of types of pumps according to various required performances.

WO 08/069124

The volute has a greater effect on the performance of the pump compared to the shaft support described above. Therefore, it is extremely important to form a volute suitable for each of a plurality of types of pumps depending on the required performance. However, forming different volute parts for each of a plurality of types of pumps is not a practical solution. The reason is that in the conventional pump, the volute portion is integrally formed with the portion constituting the outer shell of the pump as a part of the casing by integral molding. More specifically, the reason why the above-mentioned countermeasure is not realistic is that, in the case of forming different volutes depending on the required performance of the pump, the entire casing of each of a plurality of types of pumps has a different structure It is necessary to form in

On the other hand, in recent years, there is an increasing need for pumps having high heat resistance and high water pressure resistance. Therefore, it is necessary to use an expensive resin material such as engineering plastic for the casing. Therefore, depending on the required performance, if the entire casing of each of the plurality of types of pumps is formed into a different structure, the cost of the pump will increase.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide various pumps according to the required performance without forming the entire casings of a plurality of types of pumps into different structures. .

In order to solve the above-mentioned conventional problems, a pump according to the present invention includes a suction flow passage, a pump chamber communicating with the suction flow passage, and a casing forming an outer shell of a discharge flow passage communicating with the pump chamber; A volute portion formed as a component independent of the casing in the pump chamber so as to form an outer shell of a spiral flow path communicating with each of the flow path and the discharge flow path; And an impeller, which is accommodated in the pump chamber so as to fit, and which discharges the liquid, which has flowed into the spiral flow passage from the suction flow passage, to the discharge flow passage.

According to the present invention, it is possible to provide various pumps according to required performance without forming the entire casings of a plurality of types of pumps into different structures.

It is sectional drawing when the pump of Embodiment 1 of this invention is cut along the plane containing the rotation center axis of the impeller. It is a top view which shows the casing of the pump of Embodiment 1 of this invention. It is a perspective view when the inside part of the casing of the pump of Embodiment 1 of this invention is seen. It is a figure which shows the volute part of the pump of Embodiment 1 of this invention, Comprising: It is a perspective view when the surface by the side of a casing of a volute part is seen. It is a figure which shows the volute part of the pump of Embodiment 1 of this invention, Comprising: It is a perspective view when the volute part is seen from the surface by the side of a pump chamber. It is a figure which shows the spacer of the pump of Embodiment 1 of this invention, Comprising: It is a perspective view when the surface by the side of a casing is looked at. It is a figure which shows the spacer of the pump of Embodiment 1 of this invention, Comprising: It is a perspective view when the surface by the side of a separating plate is looked at on a spacer. It is a perspective view when the casing of the pump of the modification of Embodiment 1 of this invention is seen from the inner surface of a pump. It is a perspective view when the volute part of the modification of Embodiment 1 of this invention is seen from the surface by the side of a casing.

A pump according to a first embodiment of the present invention includes: a suction flow passage; a pump chamber communicating with the suction flow passage; and a casing forming an outer shell of a discharge flow passage communicating with the pump chamber; The volute portion provided as a component independent of the casing in the pump chamber and the volute flow path so as to form an outer shell of the flow path communicating with each of the discharge flow path And an impeller, which is accommodated in the pump chamber and sends out the liquid flowing from the suction flow path to the spiral flow path to the discharge flow path.

According to this, it is possible to provide various pumps according to the required performance without forming the respective casings of a plurality of types of pumps in different structures.

The pump according to the second embodiment of the present invention is, in particular, the pump according to the first embodiment described above, wherein the rotation center shaft extends along the direction in which the rotation center axis of the impeller extends, and the rotation center shaft And a shaft support portion for supporting the volute portion, and the volute portion and the shaft support portion are formed as an integral structure by integral molding.

According to this, the volute portion and the shaft support portion can be formed in one molding process with one mold.

In the pump of the third embodiment of the present invention, in particular, in the pump of the first embodiment described above, the downstream end of the suction passage extends along the direction in which the rotation shaft extends. The flow passage extending from the upstream portion of the suction flow passage to the downstream end of the suction flow passage has a curved shape.

According to this, the flow of the liquid sucked into the pump chamber can be made smooth.

In the pump according to the fourth embodiment of the present invention, in particular, in the pump according to the first embodiment described above, the upstream end of the discharge flow passage is the outer end of the spiral flow passage It extends to be continuous with the part.

According to this, the flow of the liquid expelled from the pump chamber can be made smooth.

According to the fifth embodiment of the present invention, in particular, in the pump according to any one of the first to fourth embodiments described above, in the region inside the volute portion, the central portion of the spiral flow path An opening communicating with the suction flow passage is formed so as to configure the casing, and a portion on the casing side of the volute has an annular protrusion extending along the outer periphery of the opening. .

According to this, it is possible to form the volute portion so that the flow passage in the opening of the volute portion communicates with the suction flow passage of the casing by using the protrusion of the volute portion.

According to a sixth embodiment of the present invention, in particular, in the pump according to any of the fifth embodiment described above, the upper surface of the annular projection forms the part of the suction flow passage, and the upper surface of the annular protrusion It has a flat surface continued to the inner surface which constitutes the suction channel.

According to this, the inner surface of the suction flow passage and the upper surface of the protrusion are continuous. Therefore, there is no stepped portion between the suction flow passage and the upper surface of the protrusion. As a result, the liquid flows smoothly in the path from the suction flow path to the upper surface of the projection. Thus, the pump efficiency can be enhanced.

According to the seventh embodiment of the present invention, in particular, in the pump of the sixth embodiment described above, the annular protrusion has a curved surface continuous with the upper surface, and the curved surface is formed from the suction flow channel It is curved to direct liquid to the center of the spiral channel in the opening.

According to this, a sharp bend is not formed between the suction flow passage and the pump chamber. As a result, the liquid flows smoothly in the flow path from the suction flow path to the pump chamber. Thus, the pump efficiency can be increased.

According to the eighth embodiment of the present invention, in particular, in the pump according to any one of the fifth to seventh embodiments, the inner surface constituting the suction passage and the inner peripheral surface of the opening are continuous. As a result, a part of the upper surface of the annular projection is closed by the casing.

According to this, from the inner surface which comprises the suction flow path of a casing to the internal peripheral surface of an opening part, an acute-angled curved part is not formed between a suction flow path and a pump chamber. As a result, the liquid flows smoothly in the flow path from the suction flow path to the pump chamber. Thus, the pump efficiency can be increased.

In the pump according to the ninth embodiment of the present invention, in particular, in the pump according to any of the fifth to eighth embodiments described above, the volute portion has an outer periphery protruding from an outer peripheral surface of the annular protrusion. It has a projection, and the casing has an L-shaped groove for receiving the outer peripheral projection at a position corresponding to the outer peripheral projection.

This prevents the volute portion and the casing from being separated from each other in the direction in which the central shaft extends.

In the pump according to the tenth embodiment of the present invention, in particular, in the pump according to any of the first to ninth inventions described above, the casing has a casing recess on the surface facing the pump chamber side. The volute portion includes a volute convex portion inserted in the casing concave portion on a surface facing the casing side.

According to this, the casing and the volute portion can be positioned.

The pump according to the eleventh embodiment of the present invention is, in particular, the pump according to any of the first to tenth embodiments described above, in which the casing faces the volute portion and the casing of the volute portion. The faces facing each other have a fitting relationship with each other.

According to this, the fixing of the positional relationship between the casing and the volute portion is stabilized.

In the pump according to the twelfth embodiment of the present invention, in particular, in the pump according to any one of the first to eleventh embodiments described above, an elastic material is disposed between the volute portion and the casing. There is.

According to this, the dispersion of the dimensions of the volute portion and the casing in the direction in which the rotation center shaft extends is absorbed by the elastic material. Therefore, the volute portion and the casing can be prevented from colliding due to the vibration of the volute portion, that is, so-called rattling can be prevented.

The pump according to the thirteenth embodiment of the present invention is, in particular, the pump according to the first embodiment described above, wherein the magnetic follower connected to the impeller and rotated by an electromagnetic force, and one end thereof are closed And a flange portion having an annular convex portion protruding outward from the opening at the other end of the cylindrical portion and protruding along the central axis direction of the cylindrical portion, A separation plate that forms a space for housing the impeller, the rotation center shaft, and the magnetic driven portion together with the casing and the volute portion, and is disposed along the outer periphery of the impeller; An annular spacer is provided between the volute portion and the separation plate so as to reduce a gap between the separation plate and the inner peripheral portion of the flange portion.

According to this, it is possible to reduce as much as possible the amount of liquid flowing into the space in which the magnetic driven portion is stored from the gap between the outer peripheral portion of the impeller and the inner peripheral portion of the flange portion of the separating plate.

In a pump according to a fourteenth embodiment of the present invention, in particular according to the thirteenth invention, the annular spacer has a spacer protrusion projecting from a surface facing the volute portion, and the volute portion is A volute recess is provided on the annular spacer facing surface and receives the spacer protrusion.

According to this, the positional deviation between the annular spacer and the volute portion is prevented.

A pump according to a fifteenth embodiment of the present invention is, in particular, the pump according to the thirteenth or fourteenth embodiment described above, comprising: a cover flange portion covering the flange portion of the separating plate; and the cylindrical shape of the separating plate A cover inner peripheral surface covering the inner peripheral surface of the housing, and the spacer is provided on the annular convex portion in a region inside the annular convex portion of the flange portion of the separator. The annular rib extends along and protrudes from a surface of the annular spacer on the side of the separation plate, and the annular rib presses the cover flange toward the flange of the separation plate.

According to this, the position of the separating plate cover is fixed in a state in which the cover flange portion is sandwiched between the separating plate and the spacer. Therefore, the position of the separating plate cover is firmly fixed.

Hereinafter, a pump according to an embodiment of the present invention will be described with reference to the drawings. The present invention is not limited by the embodiment. Also, in the following, the direction in which the rotation center shaft of the impeller extends is defined as the front-rear direction. The direction from the rotation center shaft to the suction port in the direction in which the rotation center shaft extends is defined as the forward direction. The direction opposite to the forward direction is defined as the backward direction. The pump of embodiment is demonstrated on such a premise.

Embodiment 1
First, an outline of a pump according to a first embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 1, the pump 1 includes a pump main body 10 forming an outer shell thereof, a rotary body storage chamber 51 formed in the pump main body 10, and a rotary body 20 stored in the rotary body storage chamber 51. And.

The pump body 10 is provided with a casing 30 and a volute portion 130 which is formed as a component independent of the casing 30 and in which a pump chamber 131 opened toward the rear is formed. The surface of the casing 30 facing the volute portion 130 and the surface of the volute portion 130 facing the casing 30 have a fitting relationship with each other. This fitting is preferably a clearance fit.

The pump body 10 is provided with a drive block 40 in which a storage portion 41a that opens forward is formed. As described later, the spacer 140 may be provided as a member constituting the pump main body 10 as necessary.

The drive block 40 is positioned behind the casing 30 and the volute portion 130. A later-described storage portion 41 a of the drive block 40 is in communication with the pump chamber 131 of the volute portion 130. The housing portion 41 a and the pump chamber 131 constitute a rotary body storage chamber 51 for housing the entire rotary body 20.

The drive block 40 has a separating plate 41, a magnetic drive unit 42, a control unit 43, and a mold resin 44 forming an outer shell of the drive block 40.

The separation plate 41 is formed of a synthetic resin, for example, a polyphenylene sulfide (PPS) resin. It is also possible to form the separation plate 41 using a metal that does not affect the magnetic drive.

The separation plate 41 is formed in the shape of a container that opens forward, that is, in a concave shape. The separation plate 41 is configured of a storage portion 41a and a flange portion 41d. The storage portion 41a is configured of a cylindrical peripheral wall portion 41c and a bottom surface portion 41b. The front end of the peripheral wall 41c is open, and the rear end of the peripheral wall 41c constitutes a bottom 41b of the housing 41a. That is, the storage portion 41 a has a cylindrical shape in which one end is closed. The flange portion 41 d protrudes outward in the radial direction from an end portion on the front side of the peripheral wall portion 41 c of the storage portion 41 a. In the present embodiment, the flange portion 41 d is formed over the entire circumferential length of the peripheral wall portion 41 c.

Thus, in the present embodiment, the housing 50 is configured by the casing 30, the volute portion 130 and the separation plate 41. The housing 50 forms a rotating body storage chamber 51 as a space for storing the rotating body 20. In addition, the spacer 140 may be provided as a member which comprises the housing 50 as needed like the pump main body 10. FIG.

A rear shaft fixing portion (shaft support portion) 41e which protrudes forward from the bottom surface portion is formed in a central region of the bottom surface portion 41b of the storage portion 41a (a central portion on the back side in the storage portion 41a). The rear end portion of a rotation center shaft 60 made of ceramics, which rotatably supports the rotating body 20, is fixed to the rear shaft fixing portion 41e.

The rotation center shaft 60 is fixed to the separation plate 41 and can not rotate with respect to the separation plate 41. In the present embodiment, the outline shape of the tip on the rear side of the rotation center shaft 60 is formed in a D-shape. In addition, an inner peripheral surface of the rear shaft fixing portion 41 e is formed in a D-shaped concave portion corresponding to the rear end of the rotation center shaft 60. According to this configuration, the D-shaped rear end of the rotation center shaft 60 is fitted into the D-shaped recess of the rear shaft fixing portion 41e. As a result, the rotation center shaft 60 is held in a non-rotatable state relative to the separation plate 41. As a result, the rotation center shaft 60 functions as a rotation center axis of the impeller 70 via the magnetic follower 80 described later.

The magnetic drive unit 42 is a stator. The magnetic drive unit 42 includes a stator core 42 a and a coil 42 b formed of an electromagnetic steel plate. Mold resin 44 is provided between stator core 42a and coil 42b. Therefore, stator core 42a and coil 42b are electrically isolated. The magnetic drive unit 42 is provided so as to surround the peripheral wall portion 41 c of the storage portion 41 a.

The control unit 43 is a control board that controls the magnetic drive unit 42. The control unit 43 is positioned behind the separation plate 41 and the magnetic drive unit 42. The control unit 43 is electrically connected to the coil 42 b of the magnetic drive unit 42. When the control unit 43 supplies a current to the coil 42 b of the magnetic drive unit 42, a magnetic field is generated in the magnetic drive unit 42 to rotate a magnetic driven unit 80 described later of the rotating body 20.

The mold resin 44 is formed of, for example, an unsaturated polyester resin. The mold resin 44 is provided on the outer side of the separation plate 41, and is formed by integral molding so as to include the separation plate 41, the magnetic drive unit 42, and the control unit 43.

The rotating body 20 has an impeller 70 as a pump unit, and a magnetic follower 80 provided on the rear side of the impeller 70. In the present embodiment, the impeller 70 and the magnetic follower 80 are connected. In the present embodiment, the impeller 70 and the magnetic follower unit 80 constitute a rotating body 20 as one assembly part performing a common rotational operation. That is, the impeller 70 is attached to a portion on the front side of the magnetic driven portion 80 (a portion on one end side in the direction of the rotation center shaft 60).

The magnetically driven portion 80 of the rotating body 20 is housed in the housing portion 41 a, and the impeller 70 is housed in the pump chamber 131. The magnetic driven unit 80 is a rotor which is housed in the housing portion 41 a and rotatably provided by the rotation center shaft 60 with the rotation center shaft 60 as a center axis.

The magnetically driven portion 80 is composed of a rotor portion 81 made of synthetic resin, a magnet portion 82 provided on the outer peripheral side of the rotor portion 81, and a bearing 83 provided at the center of the rotor portion 81. In the present embodiment, the rotor portion 81 is made of polyphenylene ether (PPE) resin. The magnet unit 82 is a permanent magnet made of ferrite or SmFe. The bearing 83 is made of a carbon-containing resin sliding material or ceramic.

The rotor portion 81 has a cylindrical bearing fixing portion 81a extending in the front-rear direction, and a magnet fixing portion 81b surrounding the bearing fixing portion 81a.

The bearing fixing portion 81a includes a front small diameter portion 81c and a rear large diameter portion 81d. The small diameter portion 81c is smaller in diameter than the large diameter portion 81d. The bearing 83 is inserted into the small diameter portion 81c. The bearing 83 is fixed to the inner circumferential surface of the small diameter portion 81c. A rotation center shaft 60 is inserted into the bearing 83. The rotation center shaft 60 is rotatably slidable with respect to the inner circumferential surface of the bearing 83. Therefore, the entire rotary body 20 is rotatably supported by the rotation center shaft 60 with the front and rear axis as the rotation center axis.

The magnet fixing portion 81 b is formed in a cylindrical shape. The front side portion of the inner peripheral surface of the magnet fixing portion 81b is integrally formed with the small diameter portion 81c of the bearing fixing portion 81a as an integral structure. Further, a magnet storage groove 81e is formed on the outer peripheral surface of the magnet fixing portion 81b.

A magnet portion 82 covered with a stainless steel magnet cover 82a is housed in the magnet housing groove 81e. Note that the outer peripheral surface of the magnet portion 82 may be exposed as the outer peripheral surface of the magnetic driven portion (rotor) 80 without providing the magnet cover 82 a.

The magnet unit 82 is provided on the outer peripheral portion of the rotor unit 81 and positioned inside the magnetic drive unit 42. A circumferential wall portion 41 c of the storage portion 41 a of the separation plate 41 is disposed between the magnet portion 82 and the magnetic drive portion 42. A gap d1 for allowing the magnetic follower 80 to rotate is formed between the magnet 82 and the peripheral wall 41c (in the embodiment, the separation plate cover 160).

The impeller 70 is a pump unit positioned in front of the magnetic follower unit 80. The impeller 70 is accommodated in the pump chamber 131 so as to fit in the spiral flow path of the volute portion 130. The impeller 70 includes a plurality of vanes 71 provided in the circumferential direction of the impeller 70, a rear shroud 72 covering the rear side of each vane 71, and a front shroud 73 covering the front of each vane 71 There is.

However, in the present embodiment, the blade portion 71 and the front shroud 73 are integrally formed so as to constitute an integral structure. A rear surface shroud 72 is joined to the end face on the rear side of the blade portion 71.

The rear shroud 72 is formed in a disk shape. At a central portion of the rear surface shroud 72, a connection portion 90 formed integrally with the rear surface shroud 72 and formed as an integral structure is continuous. The connecting portion 90 is continuous with the front end of the rotor portion 81.

At the time of manufacture of the pump, the magnet portion 82, the magnet cover 82a, the bearing 83 and the connection portion 90 are inserted into the same mold as the mold for molding the rear shroud 72 and the rotor portion 81. Thereby, the magnet portion 82, the magnet cover 82a, the bearing 83 and the connection portion 90, together with the rear surface shroud 72 and the rotor portion 81, are resin-molded so as to form an integral assembly. That is, the rear shroud 72 and the magnetic follower 80 are insert-molded articles.

The front shroud 73 includes a conical portion 73a whose diameter gradually decreases toward the front, and a cylindrical portion 73b formed at the front of the conical portion 73a. At the front of the cylindrical portion 73b, a suction port portion 74 penetrating in the front-rear direction is formed.

The outer peripheral edge of the front shroud 73 (the outer peripheral edge of the conical portion 73a) and the outer peripheral edge of the rear shroud 72 are radial directions of the impeller 70 when viewed along the direction in which the rotation center shaft 60 extends. At the same position. A gap is formed between the outer peripheral edge of the front shroud 73 and the outer peripheral edge of the rear shroud 72.

The gap communicates with the suction port 74 via a flow path 75 formed between the adjacent vanes 71 between the

shrouds

72 and 73. The discharge part 76 of the impeller 70 is comprised by this clearance gap.

Each blade portion 71 is formed at a position from the inner peripheral side of the front surface shroud 73 to the outer peripheral edge of the front surface shroud 73 (that is, the outer peripheral edge of the rear surface shroud 72). The front end of each blade 71 and the rear end of the conical portion 73 a of the front shroud 73 are continuous. That is, each blade 71 and the front shroud 73 are integrally formed so as to form an integral structure. On the other hand, the rear end surface of each blade portion 71 is attached to the front surface of the rear shroud 72.

Each blade 71 applies pressure in the radial direction to the liquid introduced into the flow path 75 via the suction port 74 when the impeller 70 rotates. Thus, the liquid supplied from the suction port 74 to the flow path 75 is sent to the discharger 76 and discharged from the discharger 76 into the space on the outer peripheral side of the impeller 70.

Further, in the present embodiment, the reflux hole 91 is formed in the connection portion 90 so that the liquid flowing into the space on the rear side of the impeller 70 is recirculated to the pump chamber 131. Preferably, the plurality of reflux holes 91 are formed along the circumferential direction of the connection portion 90.

FIG. 2 shows a plan view of a casing of the pump according to Embodiment 1 of the present invention. Moreover, FIG. 3 shows the perspective view when the casing in the pump concerning Embodiment 1 of this invention is seen from the position of an inner side.

As shown in FIGS. 1 to 3, the casing 30 is formed in the shape of a container that opens rearward. The casing 30 has a wall 32. When the outer peripheral side rear edge of the wall portion 32 abuts on the front outer peripheral end of the flange portion 41 d, the casing 30 covers the front portion of the storage portion 41 a.

The casing 30 constitutes an outer shell of a suction flow passage 35 a, a pump chamber 131 communicating with the suction flow passage 35 a, and a discharge flow passage 36 a communicating with the pump chamber 131. The casing 30 is attached to the drive block 40 by attaching the outer periphery of the wall 32 to the outer periphery of the drive block 40 including the flange 41d with a plurality of screws, screws or the like (not shown). At this time, the sealing material 100 is provided between the casing 30 and the flange portion 41 d. Therefore, the water tightness of the rotating body storage room 51 is secured.

Further, a suction pipe 35 and a discharge pipe 36 are attached to the wall portion 32 of the casing 30. The suction pipe 35 is connected to a pipe or the like (not shown), and is configured to introduce the liquid into the pump chamber 131. The discharge pipe 36 is connected to a pipe or the like (not shown), and is configured to discharge the liquid in the pump chamber 131 to the outside (a connected pipe or the like).

A space inside the suction pipe 35 is a suction flow path 35a, and a space on the upstream side of the suction flow path 35a is in communication with a suction port 35b communicating with a flow path such as a connected pipe. The space on the downstream side of the suction flow passage 35 a faces the suction port 74 of the impeller 70 and forms an opening 35 c into which the volute portion 130 is inserted.

In the present embodiment, the suction passage 35a has a curved shape. A space on the upstream side of the suction passage 35 a extends in a direction intersecting the direction of the rotation center shaft 60. On the other hand, the space on the downstream side of the suction passage 35 a extends along the direction in which the rotation center shaft 60 extends. Therefore, the suction port 35b is directed in a direction (vertical direction in the present embodiment) intersecting the direction of the rotation center shaft 60. The opening 35 c is directed to a space on the rear side in the direction in which the rotation center shaft 60 extends (a space on the impeller 70 side).

On the other hand, the space inside the discharge pipe 36 constitutes a discharge flow path 36a. At a position downstream of the discharge flow passage 36a, a discharge port 36b communicating with the flow passage such as the connected pipe is formed. Further, the discharge port 36b is also directed in a direction (vertical direction in the present embodiment) which intersects the rotation center shaft 60 direction.

Furthermore, in the present embodiment, a straight line perpendicular to the plane including the opening of the suction port 35b and a straight line perpendicular to the plane including the opening of the discharge port 36b are perpendicular to the direction in which the rotation center shaft 60 extends. , Passing through a straight line passing through the rotation center shaft 60. That is, the suction port 35 b and the discharge port 36 b are arranged such that a straight line connecting the center of the suction port 35 b and the center of the discharge port 36 b intersects perpendicularly with the straight line passing through the rotation center shaft 60. By doing this, the pump 1 can be attached to a part of the linearly arranged piping.

Further,

screw threads

35d and 36d are formed on the outer peripheral surfaces of the suction pipe 35 and the discharge pipe 36, respectively. The screw thread 35d and the screw thread 36d are connected to the pipe using a nut or the like (not shown).

Further, holding ribs 35 e and holding ribs 36 e protrude from surfaces on the center sides of the

screw threads

35 d and 36 d on the outer peripheral surface of the suction pipe 35 and the discharge pipe 36, respectively. The holding rib 35 e and the holding rib 36 e are fixed by a tool when the pump 1 is connected to a pipe.

Specifically, in the state where the holding rib 35e and the holding rib 36e are fixed by the holding tool, the pipe joint connected to the screw thread 35d and the screw thread 36d is tightened by the special tool with a predetermined tightening torque.

Further, by providing the holding rib 35e and the holding rib 36e, it is possible to make the installer of the pump recognize the necessity of fixing the holding rib 35e and the holding rib 36e by the holding tool. Therefore, it is possible to suppress that the pipe joint is attached to the

screw threads

35d and 36d in a state where the installer of the pump holds the drive block 40 with his / her hand.

Thus, if piping is attached to the pump 1 in a state where the holding rib 35e and the holding rib 36e are fixed by a tool, the pipe joint can be pumped while the builder holds the drive block 40 by his own hand. There are the following advantages compared to the case of attaching to 1.

The advantage is that it is possible to suppress the load from being applied to a screw, screw or the like that fixes the casing 30 and the drive block 40. Therefore, according to the above mounting method of piping, it is possible to more reliably suppress water leakage due to loosening of screws, screws and the like.

Further, it is desirable that the shapes of the holding rib 35 e and the holding rib 36 e be polygonal. By so doing, the holding rib 35 e and the holding rib 36 e can be held at multiple angles using the holding tool. In the present embodiment, the shapes of the holding rib 35 e and the holding rib 36 e are hexagonal.

Further, it is desirable that the centers of the polygonal holding rib 35 e and the holding rib 36 e be on a straight line connecting the centers of the suction port 35 b and the discharge port 36 b. In this way, the center of the holding tool can be positioned on a straight line connecting the center positions of the suction port 35b and the discharge port 36b of the pump 1 and the center position of the pipe. As a result, the pipe joint can be easily tightened with a dedicated tool.

In the pump of the above-described embodiment, as described above, the volute portion 130 is formed as a component independent of the casing 30. That is, the volute portion 130 and the casing 30 can be separated.

FIG. 4 and FIG. 5 are views showing a volute part in the pump of the embodiment 1 of the present invention. FIG. 4 is a perspective view when the volute portion is viewed from the position on the casing side. FIG. 5 is a perspective view when the volute is viewed from the position on the pump chamber side.

The volute portion 130 is a structure forming a spiral flow passage communicating with each of the suction flow passage 35 a and the discharge flow passage 36 a. An opening 135 communicating with the suction flow passage 35a is formed at a position on the front side of the volute portion 130 and at a radially inner position.

Specifically, the volute portion 130 is formed in a step-like shape by forming an annular protrusion 137 at a position on the front side of the rear portion 136 (a position on the casing 30 side). In the volute portion 130, an opening 135 communicating with the suction flow passage 35a is formed at a position on the front side of the projection 137 and at a radially inner position.

That is, in the portion on the casing 30 side of the volute portion 130, the annular protrusion 137 protrudes so as to surround the opening 135.

A pump chamber 131 is formed in the volute portion 130. The pump chamber 131 is formed on the outer periphery of the impeller accommodation chamber 131a circular in plan view for accommodating the impeller 70 and the impeller accommodation chamber 131a, and has a volute structure of a spiral shape in plan view to give a pressure increase effect to the liquid. And 131b.

Therefore, the liquid discharged from the discharge part 76 to the space on the outer peripheral side of the impeller 70 is introduced into the space having the volute structure 131 b. Pressure is applied to the liquid in this volute structure 131b. When the volute portion 130 is assembled to the casing 30, the volute structure 131b communicates with the space on the upstream side of the discharge flow path 36a.

According to the above configuration, the liquid is discharged from the discharge part 76 of the impeller 70 to the space having the volute structure 131 b. The liquid is then pressurized in the space with volute structure 131b. As a result, the liquid is discharged to the space outside the pump 1 through the discharge port 36b of the discharge flow path 36a in a state where pressure is applied.

A protrusion (convex portion) 136 b formed on a position on the casing 30 side of the volute portion 130 (front surface 136 a of the rear portion 136) is inserted in the direction of the rotation center shaft 60 along the recess 37 provided on the inner surface of the casing 30. . Further, the outer peripheral surface 137 b of the annular protrusion 137 provided around the opening 135 is fitted into the recess 38 of the opposing casing 30. Thus, the volute portion 130 is assembled to the casing 30.

Further, in the present embodiment, the upper surface (the surface on the side of the casing 30) 137a of the protrusion 137 is formed in a planar shape. In a state where the volute portion 130 is assembled to the casing 30, a portion on the suction port 35b side (a portion on the right side in FIG. 1) of the planarly formed upper surface 137a is exposed to the suction flow passage 35a. On the other hand, the part on the opposite side to the part on the suction port 35 b side (the part on the left side in FIG. 1) is closed by the casing 30. Thus, the protrusion 137 is formed. Therefore, the portion closed by the casing 30 becomes a positioning portion in the direction in which the rotation center shaft 60 extends when the volute portion 130 is attached to the casing 30. Therefore, the assembling accuracy is improved and the assembling operation is facilitated.

That is, on the upper surface 137a of the projecting portion 137, the exposed portion 137d is formed at the position on the suction port 35b side (the position on the right side in FIG. 1) in a state where the volute portion 130 is assembled to the casing 30. Further, on the upper surface 137a of the projection 137, a closed portion 137c is formed at a position opposite to the position on the suction port 35b side.

In addition, as shown in FIG. 4, the rear surface 38a of the recessed part 38 is formed so that a width may become wide as it goes to the position on the opposite side with respect to the position by the side of the suction port 35b. A portion of the upper surface 137a of the protrusion 137 overlapping the rear surface 38a is a closed portion 137c.

Further, an arc-shaped portion (R portion) 137f is formed on the peripheral edge on the opening portion 135 side of the upper surface 137a. The arc-shaped portion (R portion) 137f is such that the portion on the suction port 35b side (the portion on the right side in FIG. 1) is the largest arc-shaped portion (R portion), that is, the arc-shaped portion positioned outermost. There is. The arc-shaped portion (R portion) 137 f becomes an arc-shaped portion (R portion) which gradually becomes smaller toward the opposite side to the portion on the suction port 35 b side, that is, an arc-shaped portion gradually positioned inside.

The protrusion 137 has an arc-shaped portion (R portion) 137f as a curved surface continuous with the upper surface 137a. An arc-shaped portion (R portion) 137f which is the curved surface is bent so as to guide the liquid in the direction of the front shaft fixing portion (shaft supporting portion) 133 side.

Further, the volute portion 130 has a front shaft fixing portion (shaft support portion) 133 located at the central portion of the rotating body storage chamber 51. The front end portion of the rotation center shaft 60 on the front side is fixed to the front shaft fixing portion 133.

The rotation center shaft 60 is held by the separation plate 41 so as not to rotate. The casing 30 and the separation plate 41 are fixed. Also, the volute portion 130 is fixed to the casing 30. Therefore, the front end portion of the rotation center shaft 60 may not be held so as not to be rotated by the front shaft fixing portion 133 of the volute portion 130. The reason is that the relative rotation of the rotation center shaft 60 with respect to the volute portion 130 is limited by the separation plate 41.

In the present embodiment, the front shaft fixing portion 133 is integral with the volute portion 130 via a plurality (three in the present embodiment) of support ribs 134 extending from the position on the inner surface side of the protrusion 137 toward the pump chamber 131. Is formed. That is, in the present embodiment, the volute portion 130 and the front shaft fixing portion 133 are integrally formed as an integral structure. However, in the present invention, the front shaft fixing portion 133 does not have to be formed as an integral structure with the volute portion 130. In the present invention, each of the volute portion and the front shaft fixing portion may be formed as an independent structure by separate molding processes.

The front shaft fixing portion 133 has a cylindrical (conical) protruding portion 133 a protruding toward the front, and a tubular portion connected to the rear of the protruding portion 133 a to support the front end of the rotation center shaft 60. And a bearing portion 133b.

Reference numeral 110 in FIG. 1 denotes a bearing plate that receives a load in the thrust direction applied to the bearing 83, and reference numeral 120 denotes a shock absorbing material that absorbs vibration or the like of the rotation center shaft 60.

Further, an elastic member 150 is disposed between the casing 30 side of the volute portion 130 and the casing 30. In the present embodiment, the elastic member 150 is an O-ring.

Thus, the elastic member 150 is disposed between the casing 30 side of the volute portion 130 and the casing 30. Generally, there may be variations in the dimensions of volute portion 130 and casing 30 in the direction in which rotation center shaft 60 extends. In this case, the front shaft fixing portion 133 may vibrate (wobble) in the direction in which the rotation center shaft 60 extends due to the variation. However, in the pump of the present embodiment, the elastic material 150 suppresses the generation of the above-mentioned vibration.

It is desirable that a material having high heat resistance, high rigidity, and high hardness be used as the material of the casing 30. In the present embodiment, the casing 30 is formed of PPS resin. On the other hand, volute portion 130 is formed of PPE resin because it requires less strength than casing 30.

As described above, in the pump according to the present embodiment, the volute portion 130 having the front shaft fixing portion 133 is formed as an integrally molded part independent of the casing 30, ie, separately from the casing 30. The volute portion 130 and the front shaft fixing portion 133 are not adversely affected by water pressure. Therefore, the materials of the volute portion 130 and the front shaft fixing portion 133 do not require more strength than the material of the casing 30. Therefore, the volute portion 130 and the front shaft fixing portion 133 can be formed of a cheaper material.

The pump 1 described above is driven by the control unit 43 causing a current to flow through the coil 42 b. When a current flows in the coil 42b, a magnetic field is generated in the magnetic drive unit 42. Thereby, the magnet unit 82 provided on the rotating body 20 is attracted to the magnetic drive unit 42 or repelled to the magnetic drive unit 42. As a result, the magnetic follower 80 rotates around the rotation center shaft 60 with the rotation center shaft 60 as a center axis. Thus, the impeller 70 rotates around the rotation center shaft 60 with the rotation center shaft 60 extending back and forth as a rotation center axis.

When the impeller 70 rotates, the liquid introduced into the flow path 75 of the impeller 70 via the suction port 74 is discharged from the discharge portion 76 to the space on the outer peripheral side of the impeller 70. The liquid discharged into the space on the outer peripheral side of the impeller 70 is basically introduced into the space having the volute structure 131 b. At this time, pressure is applied to the liquid in the space having the volute structure 131 b. Thereafter, the liquid is discharged to the space outside the pump 1 via the discharge port 36b in a state where pressure is applied in the volute structure 131b.

A portion of the liquid passes through the gap d3 of the flange portion between the outer peripheral edge of the rear surface shroud 72 and the flange portion 41d of the separation plate 41, flows into the space behind the rear surface shroud 72, and flows into the storage portion 41a. I assume.

At this time, if foreign matter (magnetic material such as iron powder) that may adhere to the magnet unit 82 is mixed in the liquid, foreign matter (magnetic material such as iron powder) adheres to the magnet unit 82. In this case, the rotation of the rotating body 20 may be inhibited or locked.

Therefore, in the present embodiment, the separation plate cover 160 formed of SUS is provided on the inner surface of the separation plate 41. Thereby, it is possible to suppress that the foreign matter (magnetic material such as iron powder or the like) which has entered the storage portion 41a and is attracted to the magnet portion 82 is rotated with the magnetic driven portion 80 to damage the inner surface of the separation plate 41. .

Further, in the present embodiment, an annular spacer 140 is disposed on the inner circumferential surface of the opening of the separation plate 41.

6 and 7 are views showing a spacer in the pump of the first embodiment of the present invention. FIG. 6 is a perspective view of the spacer on the side of the casing. FIG. 7 is a perspective view of the spacer on the side of the separating plate.

The spacer 140 is formed of resin, and as shown in FIGS. 1, 6 and 7, the end surface 140 a on the casing 30 side of the spacer 140 constitutes a part of the volute structure 131 b. The outer peripheral portion of the casing 30 side end surface 140 a is pushed by the rear end surface 130 a of the volute portion 130. Thus, the spacer 140 is fixed by interposing the outer peripheral portion of the casing 30 side end surface 140 a between the rear end surface 130 a and the separation plate 41.

In addition, the protrusion 140b is formed on the casing 30 side end surface 140a. The protrusion 140 b is inserted into the recess 130 b in the rear end surface 130 a of the volute portion 130. Thereby, the rotation of the spacer 140 is prevented.

Furthermore, in the present embodiment, an annular rib 140c is formed at a position on the rear side of the spacer 140 so as to protrude along the inner circumferential surface of the opening of the separation plate 41. The annular rib 140 c presses the flange portion 160 a of the separating plate cover 160. Thus, the position is fixed in a state where the separation plate cover 160 is sandwiched by the separation plate 41 and the spacer 140.

In the present embodiment, the flange portion 41 d is provided with an annular convex portion that protrudes along the direction in which the rotation center shaft 60 extends, that is, the direction in which the central axis of the cylindrical portion extends. The impeller 70 having a large gap between the outer peripheral portion of the impeller 70 and the inner peripheral portion of the annular convex portion of the flange portion 41 d is used. Therefore, the spacer 140 is disposed along the outer periphery of the impeller 70. Thus, the gap between the outer peripheral portion of the impeller 70 and the inner peripheral portion of the annular convex portion of the flange portion 41 d is reduced.

However, in the case of using the impeller 70 (the impeller 70 having a large outer diameter) in which the gap between the outer peripheral portion of the impeller 70 and the inner peripheral portion of the flange portion 41d is not large in order to enhance the pump efficiency. The spacer 140 need not be used.

As described above, the pump 1 includes the suction flow passage 35a, the pump chamber 131 communicating with the suction flow passage 35a, and the casing 30 forming an outer shell of the discharge flow passage 36a communicating with the pump chamber 131. The pump 1 also has an impeller 70 housed in the pump chamber 131 and a rotation center shaft 60 functioning as a rotation center axis of the impeller 70.

The pump 1 includes a volute unit 130. The volute portion 130 includes a front shaft fixing portion (shaft support portion) 60 that communicates with the suction flow path 35 a and the discharge flow path 36 a and supports the rotation center shaft 60. The volute portion 130 is formed as a component independent of the casing 30 in the pump chamber 131.

Thus, the volute portion 130 having the front shaft fixing portion (shaft support portion) 133 supporting the one end of the shaft 60 during rotation is formed separately from the casing 30. Thereby, a plurality of types of volute sections 130 can be formed according to various pump performances. Thus, only the volute portion 130 can be replaced in a state in which the portion other than the volute portion 130 of the casing 30 is left.

As a result, in the plurality of types of pumps 1, for example, a casing 30 made of an expensive resin material having high heat resistance, high rigidity, and high hardness can be used as a common component. On the other hand, different volute units 130 may be used depending on various pump performances. Therefore, for example, the volute portion 130 can be made of a material cheaper than the casing 30.

As described above, according to the pump 1 of the present embodiment, the pump 1 is provided that is compatible with various required pump performances without forming the entire casing 30 as multiple types of parts having different structures. be able to.

Further, in the present embodiment, the suction port 35b of the suction flow path 35a and the discharge port 36b of the discharge flow path 36a face in the direction intersecting with the direction in which the rotation center shaft 60 extends. In addition, the suction flow passage 35a is curved so that the direction in which the liquid flowing in the flow passage on the downstream side travels is substantially parallel to the rotation center shaft 60 direction. A portion on the casing 30 side of the volute portion 130 constitutes an annular protrusion 137 which protrudes around the opening 135. The upper surface 137a of the protrusion 137 is formed in a planar shape.

Furthermore, in the protrusion 137, a portion on the suction port 35b side of the planarly formed upper surface 137a is exposed to the suction flow passage 35a. Further, a portion on the opposite side to the portion on the suction port 35 b side of the upper surface 137 a is closed by the casing 30.

Thereby, in the upper surface 137a of the projection 137 formed in a planar shape, a portion on the suction port 35b side forms a part of the suction flow passage 35a. Therefore, no sharp bends are formed in the suction flow passage 35a. As a result, the liquid flows smoothly in the suction passage 35a. Thus, the pump efficiency can be increased.

Specifically, the liquid flows along the direction that intersects the direction in which the rotation center shaft 60 extends in the upstream of the suction flow channel 35a (upstream of the curved flow channel). In addition, the liquid flows so as to be gradually displaced forward from the above-mentioned intersecting direction as it goes downstream in the suction flow channel 35a. In addition, on the downstream side of the suction flow path 35a (in the flow path after being curved), the liquid flows rearward along the direction in which the rotation center shaft 60 extends.

If the suction flow passage 35a is bent at an acute angle so that the flow of the liquid is directed to the suction port 74, the flow direction of the liquid flowing in the suction flow passage 35a changes rapidly. In this case, the liquid can not flow smoothly.

However, in the pump of the present embodiment, the upper surface 137a of the projection 137 formed in a planar shape in the inner bent portion (right side in FIG. 1) of the suction flow passage 35a is exposed to the suction flow passage 35a. It constitutes a part of the wall surrounding 35a. Therefore, the acute-angled curved part in the suction flow path 35a is not formed. As a result, the liquid in the suction flow path 35a flows smoothly. Thus, the pump efficiency can be increased.

Furthermore, when attaching the volute portion 130 having the front shaft fixing portion (shaft support portion) 133 to the casing 30, the direction in which the rotation center shaft 60 extends when the portion (closing portion 137 c) closed by the casing 30 of the projecting portion 137 Functions as a positioning unit in Therefore, the assembling accuracy of the pump 1 is improved. Further, in the present embodiment, the R portion 137f is formed on the peripheral edge on the opening 135 side of the upper surface 137a. In the circular arc portion (R portion) 137f, a portion on the suction port 35b side (right side in FIG. 1) constitutes the circular arc portion (R portion) having the largest radius of curvature. In the circular arc portion (R portion) 137f, the radius of curvature of the circular arc portion (R portion) 137f gradually decreases from the portion on the suction port 35b side toward the portion on the opposite side.

Therefore, the curved portion of the suction flow passage 35a can be formed more gently. As a result, the liquid in the suction flow path 35a flows more smoothly. As a result, the pump efficiency can be further enhanced.

Further, in the present embodiment, the elastic material 150 is disposed between the volute portion 130 and the casing 30. As a result, the variation in dimension in the direction in which the rotation center shaft 60 extends is absorbed by the elastic member 150. Therefore, so-called rattling that the front shaft fixing portion (shaft support portion) 133 collides with a surrounding portion due to vibration does not occur. Thereby, the front shaft fixing portion (shaft support portion) 133 of the volute portion 130 can be stably attached to the casing 30.

Next, modifications of the casing and the volute portion will be described.

FIG. 8 is a perspective view when looking at the inner surface of the casing of the modification of the first embodiment of the present invention. FIG. 9 is a perspective view of the volute portion of the modification of the first embodiment of the present invention as viewed from the side of the casing.

The casing 30A and the volute portion 130A basically have the same configuration as the casing 30 and the volute portion 130 described in the first embodiment.

Here, differences between the casing 30A and the volute portion 130A from the casing 30 and the volute portion 130 described in the first embodiment will be mainly described. In the pump of this modification, a protrusion 137e is provided on the outer peripheral surface 137b of the protrusion 137 of the volute portion 130A, and an L-shaped groove 38b is provided in the recess 38 of the casing 30A corresponding to the protrusion 137e. The point is different from the pump of the first embodiment.

In the pump of the modification, the protrusion 137e is inserted along the groove 38b and then rotated about the central axis of rotation at the deepest position of the groove 38b. Thus, the volute portion 130A is fixed to the casing 30.

The above-described pump of the present modification also provides the same operation and effect as the operation and effect obtained by the pump of the first embodiment.

Further, in the pump of the present modification, the protrusion 137e and the groove 38b are formed as a retaining structure that prevents the volute portion 130A and the casing 30A from being separated from each other. Therefore, in addition to the operation and effects obtained by the pump of the embodiment described above, an effect is also obtained that the volute portion 130A and the casing 30A can be easily assembled.

As mentioned above, although the suitable embodiment of the present invention was described, the present invention is not limited to the above-mentioned embodiment, and it is possible to add various modification to a pump of the above-mentioned embodiment.

For example, in the above embodiment, as an example of the pump of the present invention, a canned motor pump is exemplified in which the suction pipe and the suction flow path are curved and can be attached to a part of linearly arranged piping. . However, in the pump of the present invention, the direction in which each of the suction pipe and the suction flow path extends substantially coincides with the direction in which the rotation center shaft extends, and can be attached to a corner or the like of the L-shaped bent pipe. It may be a canned motor pump.

In addition, the specifications (shape, size, layout, etc.) of the casing, the suction pipe, and other details may be changed as appropriate.

As described above, in the pump of the present invention, the volute portion is formed as a separate part from the casing and attached to the casing. Such a pump can be applied to, for example, a pump incorporating a line piping type that forms a suction flow passage in a casing by die cutting.

Reference Signs List 1 pump, 30, 30A casing, 35a suction flow channel, 35b suction port, 36a discharge flow channel, 36b discharge port, 60 rotation center shaft, 70 impellers, 130, 130A volute section, 131 pump chamber, 133 front shaft fixing section (Shaft support), 135 opening, 137 protrusion, 137a top surface, 150 elastic material.

Claims

A suction channel, a pump chamber communicating with the suction channel, and a casing forming an outer shell of a discharge channel communicating with the pump chamber;
A volute portion provided as a component independent of the casing in the pump chamber so as to form an outer shell of a spiral flow passage communicating with each of the suction flow passage and the discharge flow passage;
A pump which is accommodated in the pump chamber so as to fit in the spiral flow path, and which discharges the liquid flowing from the suction flow path into the spiral flow path to the discharge flow path .
A rotation center shaft extending along a direction in which the rotation center axis of the impeller extends;
And a shaft support portion for supporting one end of the rotation center shaft.
The pump according to claim 1, wherein the volute portion and the shaft support portion are integrally formed as an integral structure.
The downstream end of the suction flow path from the upstream portion of the suction flow path so that the downstream end of the suction flow path extends along the direction in which the rotation central axis of the impeller extends A pump according to claim 1 or 2, wherein the flow path leading to it has a curved shape.
The pump according to any one of claims 1 to 3, wherein an upstream end of the discharge flow channel extends in communication with an outer peripheral end of the spiral flow channel.
An opening communicating with the suction flow passage is formed in a region inside the volute portion so as to form a central portion of the spiral flow passage,
The pump according to any one of claims 1 to 4, wherein the casing-side portion of the volute portion has an annular protrusion extending along the outer periphery of the opening.
The pump according to claim 5, wherein the upper surface of the annular protrusion has a flat surface continuous with the inner surface of the suction channel of the casing so as to form a part of the suction channel.
The annular protrusion has a curved surface continuous with the upper surface,
7. The pump of claim 6, wherein the curved surface is curved to direct liquid from the suction channel to the central portion of the spiral channel in the opening.
The upper surface of the annular projection is partially closed by the casing so that the inner surface of the suction passage and the inner circumferential surface of the opening are continuous with each other. Description pump.
The volute portion has an outer peripheral protrusion that protrudes from an outer peripheral surface of the annular protrusion portion,
The pump according to any one of claims 5 to 8, wherein the casing has an L-shaped groove for receiving the outer peripheral projection at a position corresponding to the outer peripheral projection.
The casing includes a casing recess on the surface facing the pump chamber side,
The pump according to any one of claims 1 to 9, wherein the volute portion includes a volute convex portion inserted in the casing concave portion on a surface facing the casing side.
The pump according to any one of claims 1 to 10, wherein a surface of the casing facing the volute portion and a surface of the volute portion facing the casing have a fitting relationship with each other.
The pump according to any one of claims 1 to 11, further comprising an elastic material provided between the volute portion and the casing.
A magnetic follower connected to the impeller and rotated by an electromagnetic force;
A cylindrical portion having one end closed and a flange portion having an annular convex portion protruding outward from the opening at the other end of the cylindrical portion and protruding in the central axis direction of the cylindrical portion A separation plate that forms a space for housing the impeller and the magnetic follower together with the casing and the volute portion;
The volute portion is disposed along the outer periphery of the impeller so as to reduce a gap between the outer periphery of the impeller and the inner periphery of the annular convex portion of the flange portion of the separation plate The pump according to any one of claims 1 to 12, further comprising an annular spacer provided between the separation plate and the separation plate.
The annular spacer has a spacer protrusion projecting from the surface facing the volute portion,
The pump according to claim 13, wherein the volute portion has a volute recess provided on a surface facing the annular spacer and receiving the spacer protrusion.
The separation plate cover includes a cover flange portion covering the flange portion of the separation plate, and a cover inner circumferential surface portion covering the inner circumferential surface of the cylindrical portion of the separation plate.
The spacer includes an annular rib which extends along the annular convex portion in a region inside the annular convex portion of the flange portion of the separator plate and which protrudes from a surface of the spacer on the separator plate side. ,
The pump according to claim 13, wherein the annular rib presses the cover flange toward the flange of the separating plate.