JP2019068702A - Canned electric rotating machine - Google Patents

Abstract

To provide a canned electric rotating machine which does not cause can loss and of which the can is easily manufactured.SOLUTION: A canned electric rotating machine includes a large diameter cylindrical frame 4, a small diameter cylindrical can 9, a load side frame side plate 1, a non-load side frame side plate 13, a stator chamber F defined by the cylindrical frame 4, the can 9, the load side frame side plate 1, and the non-load side frame side plate 13, a rotor chamber R defined on the cylinder center side of the can 9, a stator 3 accommodated in the stator chamber F, and a rotor 8 housed in the rotor chamber R, and the can is made of a cellulose nanofiber sheet.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rotating electrical machine having a canned structure.

  Conventionally, as shown in FIG. 10, when the leakage of the liquid to be treated to the outside of the pump motor is not allowed, or when the entry of water into the inside of the pump motor such as the submersible motor pump and vacuum pump is not allowed. A canned rotary electric machine (canned motor) is used. In the rotating electrical machine having the canned structure of FIG. 10, the can 109 separates the rotor 108 from the stator 103 (consisting of a stator core and a stator winding 110). The can 109 generally has a cylindrical shape and is attached to the inner surface of the core portion of the stator 103 with the rotor 108 completely closed. Usually, metal cans are used from the viewpoint of durability and water resistance, but since metal cans have conductivity, when the magnetic flux generated by the stator rotates, eddy currents are generated inside the cans. It flows and losses occur. Such loss is referred to as a can loss, and there is a problem that the can loss significantly reduces the motor efficiency. In addition to this, in the case of a metal can, welding is necessary to form a thin metal plate into a cylindrical shape, but it is difficult to weld a thin metal plate so as not to cause a step, and Since welding itself is difficult depending on the type of metal material, there is a problem that it is difficult to manufacture a metal can.

  In order to solve the problem resulting from such metal cans, it has been proposed to use fiber cans made of fiber reinforced plastic or resin instead of metal cans (Patent Documents 1 to 3).

  In Patent Document 1, a stator core loaded with a stator winding is inserted and fixed in a cylindrical frame, the stator winding and the stator core are surrounded by a can, and in a space surrounded by the can. In a canned rotary electric machine in which a rotor is arranged rotatably, a can is made of a resin such as polyether-ether ketone (PEEK), polyimide (PI) or the like, and a carbon fiber or the like is arranged to reinforce it. A multilayer consisting of a layer or a first layer of a fiber-reinforced plastic or plastic and a second layer of a metal-deposited layer or a ceramic-deposited layer or a thin metal plate disposed on the inner surface of the first layer It has been proposed to configure.

  In Patent Document 2, a can disposed between a stator and a rotor of a canned motor, which is formed by laminating sheet-like fiber reinforced plastics concentrically or spirally, and between the laminations, A can having a barrier layer made of gas-tight resin interposed therein has been proposed. Further, in Patent Document 3, a stator core having a stator winding loaded in a cylindrical frame is inserted and fixed, and the stator winding and the stator core are surrounded by a can and surrounded by the can. In a canned rotary electric machine in which a rotor is rotatably disposed in a space, it has been proposed that a can has a multi-layer structure including a first layer made of resin and a second layer made of sheet metal. And, as the first layer made of resin, those made of PEEK (polyether-ether ketone) or PI (polyimide) resin, or those made of fiber reinforced plastic (FRP) reinforced by arranging reinforcing fibers in the resin It is shown.

However, in the can of Patent Document 1, the gas is transmitted only by the layer of fiber reinforced plastic or the first layer made of resin, and the insulation of the coil is lowered. In the documents 2 and 3, it is essential to use a barrier layer made of gas-tight resin or a second layer made of sheet metal. The cans of Patent Documents 2 and 3 have a problem that the manufacturing process is complicated because a plurality of layers are formed, and in particular, it is difficult to weld thin sheet metal without steps to form a cylindrical shape.

JP, 2011-166944, A JP 2001-231213 A Unexamined-Japanese-Patent No. 2011-193662

  An object of the present invention is to provide a canned rotary electric machine in which can loss does not occur and manufacture of the can is easy.

As a result of earnestly researching to solve the above problems, the present inventors have found that forming a can using a layer containing cellulose nanofibers prevents can loss and facilitates manufacture of the can. And completed the present invention. Specific embodiments of the present invention are as follows.
[1] A large diameter cylindrical frame, a small diameter cylindrical can, a load side frame side plate, a non-load side frame side plate, the frame, the can, the load side frame side plate, and the non load side frame A stator chamber defined by a frame side plate, a rotor chamber defined on the cylindrical center side of the can, a stator accommodated in the stator chamber, and a rotor accommodated in the rotor chamber; A rotating electrical machine having a cand structure, wherein the can is composed of a cellulose nanofiber sheet.
[2] A large diameter cylindrical frame, a small diameter cylindrical can, a load side frame side plate, a non-load side frame side plate, the frame, the can, the load side frame side plate, and the non load side frame A stator chamber defined by a frame side plate, a rotor chamber defined on the cylindrical center side of the can, a stator accommodated in the stator chamber, and a rotor accommodated in the rotor chamber; A rotating electrical machine having a canned structure, wherein the can is composed of a two-layer sheet of a cellulose nanofiber sheet and a resin layer.
[3] The rotating electrical machine according to [1] or [2], wherein the can is connected to the load side frame side plate and the anti-load side frame side plate by an O-ring and a wedge.
[4] The can is connected to the surface of the cellulose nanofiber sheet or the surface of the two-layer sheet and the load side frame side plate and the anti-load side frame side plate by a sealing resin layer formed by blow molding The rotating electric machine according to [1] or [2].
[5] The rotating electrical machine according to [4], wherein the can is connected to the load side frame side plate and the non-load side frame side plate by an O-ring.

  The rotating electric machine having the canned structure of the present invention does not generate a can loss and the can can be easily manufactured.

It is sectional drawing which shows one aspect | mode of the rotary electric machine of the canned structure of this invention. It is an enlarged view of the can part in FIG. It is an enlarged view of the A section of FIG. 1, and shows some cans comprised from a cellulose nanofiber sheet. It is a modification of FIG. 3 and shows a part of the can comprised from the bilayer | two_layer sheet | seat of a cellulose nanofiber sheet | seat and a resin layer. It is sectional drawing which shows another one aspect | mode of the rotary electric machine of the canned structure of this invention. FIG. 6 is an enlarged view of a portion B of FIG. 5 and shows a part of a can composed of a cellulose nanofiber sheet connected by a blow-molded sealing resin layer. It is a modification of FIG. 6, and shows a part of the can comprised from the two-layer sheet | seat of the cellulose nanofiber sheet and resin layer which are connected by the blow-molded resin layer for sealing. It is a modification of FIG. 3, and shows a part of the can comprised from the blow molding resin layer for sealing, and the cellulose nanofiber sheet connected by O ring. It is a modification of FIG. 4 and shows a part of the can comprised from the two-layer sheet | seat of the cellulose nanofiber sheet and resin layer which are connected by the blow molding resin layer and O ring. It is sectional drawing which shows the rotary electric machine of the conventional cand structure.

Hereinafter, a rotating electrical machine having a canned structure according to the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing one aspect of a canned structure rotary electric machine of the present invention, FIG. 2 is an enlarged view of a can portion in FIG. 1, and FIG. 3 is an enlarged view of A part in FIG. FIG. 4 is a modification of FIG. 3 and shows a part of a can composed of a two-layer sheet of a cellulose nanofiber sheet and a resin layer.

  The rotating electrical machine having a canned structure according to the present invention comprises a large diameter cylindrical frame 4, a small diameter cylindrical can 9, a load side frame side plate 1, a non-load side frame side plate 13, and the cylindrical frame 4. A stator chamber F defined by the can 9, the load side frame side plate 1, and the non-load side frame side plate 13, a rotor chamber R defined on the cylinder center side of the can 9, and the stator chamber It has a stator 3 accommodated in F and a rotor 8 accommodated in the rotor chamber R. In FIG. 1, the upper side of the drawing is the load side (impeller side), and the lower side of the drawing is the non-load side (anti-vane side).

  As shown in the drawing, in the rotating electric machine having a canned structure, the stator chamber F and the rotor chamber R are partitioned by the can 9. In the rotor chamber R, the main shaft 2 is rotatably supported by the load side bearing 6 and the anti-load side bearing 11 arranged up and down, and the rotor 8 is provided substantially at the center of the main shaft 2 in the longitudinal axis direction. ing. In the stator chamber F, a stator 3 (consisting of a stator core and a stator winding 10) is provided at a position corresponding to the rotor 8. Both ends of the frame 4 are connected to the load side frame side plate 1 provided on the impeller side and the anti-load side frame side plate 13 provided on the non-impeller side, and the load side frame side plate 1 is on the load side It is fixed to the bracket 5. The outer peripheral surface of the cylindrical can 9 is in close contact with the inner peripheral surfaces of the stator 3, the load side frame side plate 1 and the anti-load side frame side plate 13, and between the load side frame side plate 1 and the anti load side frame side plate 13 The stator chamber F in which the stator 3 is disposed is sealed by interposing the load side O-ring 7 and the non-load side O-ring 12 respectively. The can 9 is connected to the load side frame side plate 1 and the anti-load side frame side plate 13 by the load side wedge 15 provided on the load side and the anti-load side wedge 16 provided on the non-load side.

  The can 9 is formed by forming the cellulose nanofiber sheet shown in FIG. 3 in a cylindrical shape, or formed by forming a two-layer sheet of the cellulose nanofiber sheet 9a and the resin layer 9b shown in FIG. 4 in a cylindrical shape. In the conventional rotating electric machine having a canned structure as shown in FIG. 10, the metal can 109 is fixed to the load side frame side plate 101 and the non-load side frame side plate 113 by welding, but the canned shown in FIGS. In the rotating electric machine having the structure, the can 9 can be easily fixed by the load side wedge 15 and the non-load side wedge 16 without welding.

FIGS. 5-9 show alternative embodiments of FIGS. 5-9, the same code | symbol is attached | subjected to the same structure as FIGS. 1, 3-4, and description is abbreviate | omitted.
FIG. 5 is a cross-sectional view showing another aspect of the canned structure rotary electric machine of the present invention, and FIG. 6 is an enlarged view of a portion B of FIG. FIG. 7 is a modification of FIG. 6 and shows a part of a can composed of a two-layer sheet of a cellulose nanofiber sheet and a resin layer. In the embodiment shown in FIGS. 5 to 7, the outer peripheral surface of the cylindrical can 9 shown in part B is replaced with the stator 3 in place of the connection by the wedge and O ring shown in part A in the embodiment shown in FIGS. Stator chamber F in which the stator 3 is disposed between the load side frame side plate 1 and the non-load side frame side plate 13 in close contact with the inner peripheral surfaces of the load side frame side plate 1 and the non-load side frame side plate 13 Of the cellulose nanofiber sheet 9 (FIG. 6) or the cellulose nanofiber sheet 9a and the resin layer 9b (FIG. 7) and the load side frame side plate 1 and the anti The load side frame side plates 13 are connected by a blow molded sealing resin layer.

  Alternatively, as shown in FIGS. 8 and 9, instead of the wedges shown in FIGS. 3 and 4, an O-ring is provided between the cellulose nanofiber sheet 9 (FIG. 8) or 9a (FIG. 9) and the negative frame side plate 1 After interposing, the outer peripheral surface of the cylindrical can 9 is in close contact with the inner peripheral surfaces of the stator 3, the load side frame side plate 1, and the anti-load side frame side plate 13, and the load side frame side plate 1 and the anti load side frame Cellulose nanofiber sheet 9 (FIG. 8) or two of cellulose nanofiber sheet 9a and resin layer 9b so as to define in a sealed state stator chamber F in which stator 3 is disposed between side plate 13 and The surface of the layer sheet (FIG. 9) and the load side frame side plate 1 and the reverse load side frame side plate 13 may be connected by a blow molded sealing resin layer.

  In one aspect of the invention, the can 9 is formed from a cellulose nanofiber sheet. Cellulose nanofibers are the microfibrils of cellulose which comprises the basic skeleton of a plant cell wall, etc., or the fiber which comprises this, and using conventionally well-known things as a cellulose nanofiber, without being specifically limited Can. In the present invention, the cellulose nanofiber sheet includes a sheet, a film or a paper made of cellulose nanofibers or a fiber reinforced plastic reinforced by cellulose nanofibers. As the cellulose nanofibers dispersed in the fiber reinforced plastic, those having a hydrophobic treatment are preferable from the viewpoint of improving the dispersibility in the resin.

A known method can be used without limitation as a method of forming a cellulose nanofiber sheet, for example, a method of applying a coating liquid containing cellulose nanofibers to a substrate and peeling the cellulose nanofiber sheet from the substrate after drying A method of applying a coating liquid containing cellulose nanofibers to a substrate and drying it to form a laminate sheet of the substrate and a layer containing cellulose nanofibers can be used. The can 9 can be easily manufactured by cylindrically winding a cellulose nanofiber sheet, or by cylindrically molding a resin composition containing cellulose nanofibers by a known method such as blow molding. In addition, when a resin composition containing cellulose nanofibers is formed into a sheet, wound into a cylindrical shape, and hot-pressed, a can having a higher mechanical strength can be manufactured. In this way, by forming the cellulose nanofiber sheet into a cylindrical shape, it is possible to manufacture cans seamlessly, and there is no need for joining such as welding like metal cans, which makes it difficult to use welding technology. It is possible to avoid structural defects such as leaks that cause welding defects. In addition, since cellulose nanofibers have excellent gas barrier properties and gas is difficult to be transmitted, the insulation of the coil is deteriorated without using other layers such as a gas barrier resin layer or metal layer as a layer constituting the can. Problem does not occur. In addition, since the can made of a cellulose nanofiber sheet has a high electric resistance similar to the insulating material and is a nonmagnetic material, cans such as eddy current loss and hysteresis loss even if the rotating magnetic field of the motor is generated in the can. Do not lose money. Therefore, the loss can be reduced and the motor efficiency can be enhanced. In addition, cellulose nanofiber sheets have mechanical strength and durability equal to or better than metal materials, and can be used without problems even under the same conditions as cans in which conventional metal materials are used. It is possible. In addition, a cellulose nanofiber sheet having good durability can be imparted with a function of preventing the entry of water. In addition, the cellulose nanofiber sheet has the advantages of being light and strong, having a small thermal deformation, and being renewable because of being derived from natural resources and having a low environmental impact.

  Further, in another aspect of the present invention shown in FIGS. 4 and 7, the can 9 is a cylindrical two-layer sheet of a cellulose nanofiber sheet 9a and a resin layer 9b. As the resin layer, thermoplastic resins such as polyethylene terephthalate (PET), polypropylene (PP), polyethylene (PE) and the like can be preferably used. The manufacturing method of the bilayer | two_layer sheet | seat of a cellulose nanofiber sheet and a resin layer is not specifically limited. For example, a resin layer is manufactured by blow molding of a resin such as PET, PP, PE, etc. in which the shape of the inner diameter of the stator is a mold, and a cylindrical resin layer is formed on the cellulose nanofiber sheet arranged in the inner diameter of the stator. It may be placed to form a can, or after the cellulose nanofiber sheet is placed on the inner diameter of the stator, the shape of the inner diameter of the stator is used as a mold to blow resin such as PET, PP, PE, etc. By molding, a can of a two-layer sheet of a cellulose nanofiber sheet and a resin layer can be formed. In addition, although the two-layer sheet of a cellulose nanofiber sheet and a resin layer was illustrated and demonstrated, it is not limited to a two-layer sheet, It is good also as a multilayer sheet which has three or more layers.

  As materials for forming the load-side wedge 15 and the anti-load-side wedge 16, metal materials such as iron and aluminum, and polymer materials such as engineering plastics can be used. Among these materials, those excellent in toughness and elasticity are preferable, and in particular, from the viewpoint of corrosion resistance, polymer materials are preferable.

  In the rotating electrical machine having a canned structure shown in FIGS. 1 and 5, the rotating magnetic field is generated by supplying three-phase power of a predetermined frequency and a predetermined voltage from the inverter (not shown) of the power supply to the stator winding 10 of the motor unit. As a result, the rotor 8 rotates. The load device connected to the main shaft 2 is thereby rotated. For example, when the load device is a pump, an impeller (not shown) connected to the main shaft 2 is rotated, and the pump working fluid sucked from the suction port of the pump casing is discharged from the discharge port. At this time, since the pump portion is a non-seal pump, the inside of the rotor chamber R is filled with the pump working fluid, and the working fluid is stirred by the rotor 8. While the pump hydraulic fluid of substantially the same flow rate flows, the pressure of the pump hydraulic fluid is applied. In the rotating electric machine of the cand structure shown in FIGS. 1 and 5, even when the pressure of the pump hydraulic fluid is applied to the inner peripheral surface of the can 9 as described above, the cellulose nanofiber sheet constituting the can 9 has pressure resistance and water resistance Since the can 9 is not damaged, the pump fluid can be prevented from flowing into the stator chamber F. Moreover, the cellulose nanofiber sheet which comprises can 9 has the advantage that the problem of the can loss does not generate | occur | produce like the can comprised from the conventional metal material, and the problem of the corrosion by a pump hydraulic fluid does not generate | occur | produce.

DESCRIPTION OF SYMBOLS 1 load side frame side plate 2 main axis 3 stator 4 frame 5 load side bracket 6 load side bearing 7 load side O ring 8 rotor 9 can 9 a cellulose nanofiber sheet 9 b resin layer 10 stator winding 11 anti load side bearing 12 Load side O-ring 13 Anti-load side frame side plate 15 Load side wedge 16 Anti-load side wedge 101 Load side frame side plate 102 Main shaft 103 Stator 104 Frame 105 Load side bracket 106 Load side bearing 107 Load side O ring 108 Rotor 109 Can 110 Stator winding 111 Anti load side bearing 112 Anti load side O ring 113 Anti load side frame side plate F Stator room R Rotor room

Claims (5)

By the large diameter cylindrical frame, the small diameter cylindrical can, the load side frame side plate, the non-load side frame side plate, the frame, the can, the load side frame side plate, and the non load side frame side plate A canned structure having a stator chamber defined, a rotor chamber defined on the cylindrical center side of the can, a stator accommodated in the stator chamber, and a rotor accommodated in the rotor chamber The electric rotating machine of
The can of the canned structure is characterized in that the can is made of a cellulose nanofiber sheet. By the large diameter cylindrical frame, the small diameter cylindrical can, the load side frame side plate, the non-load side frame side plate, the frame, the can, the load side frame side plate, and the non load side frame side plate A canned structure having a stator chamber defined, a rotor chamber defined on the cylindrical center side of the can, a stator accommodated in the stator chamber, and a rotor accommodated in the rotor chamber The electric rotating machine of
The can of the canned structure is characterized in that the can is composed of a two-layer sheet of a cellulose nanofiber sheet and a resin layer.   The electric rotating machine according to claim 1, wherein the can is connected to the load side frame side plate and the non-load side frame side plate by a wedge and an O-ring.   The can is connected to the surface of the cellulose nanofiber sheet or the surface of the two-layer sheet, and the load side frame side plate and the anti-load side frame side plate by a sealing resin layer formed by blow molding. The rotating electric machine according to 1 or 2. The electric rotating machine according to claim 4, wherein the can is connected to the load side frame side plate and the non-load side frame side plate by an O-ring.

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