JP6109052B2 - Canned motor - Google Patents

Description

  The present invention relates to a canned motor in which surfaces of a stator and a rotor facing each other are covered with a stator can and a rotor can, respectively.

  Conventionally, a canned motor is used in fields such as a canned motor pump.

  A stator of a canned motor includes a cylindrical stator core configured by laminating magnetic steel plates provided with a plurality of stator grooves, a stator winding disposed in the stator groove of the stator core, and It is composed of an insulating member. The rotor is arranged inside the stator and is configured to rotate by obtaining a rotational force by a rotating magnetic field generated by passing an alternating current through the stator winding. The mutually opposing surfaces of the stator and the rotor are covered with a stator can and a rotor can each formed of a thin non-magnetic plate. In the can gap between the stator can and the rotor can, a liquid such as a pump handling liquid is circulated in order to lubricate and cool the rotor bearing.

  The stator groove is opened in the inner peripheral surface of the stator core, and the width of the opening is narrower than the width of the portion where the stator winding is disposed, and has a so-called semi-closed slot shape. The stator winding is a round wire having a circular cross section, and is wound by a random winding coil system, and can be disposed in a semi-closed slot type stator groove through an opening. A winding fixing wedge for fixing the stator winding in the stator groove is provided near the opening of the stator groove.

  The stator can is disposed so as to be in close contact with the inner peripheral surface of the stator core excluding the opening of the stator groove (see, for example, Patent Document 1).

JP 2005-318713 A

  In the field of canned motors, there has been no demand for such high output, but it has been difficult to provide high-power canned motors and high-voltage canned motors exceeding 1000V class.

  In order to realize a high-power canned motor, the round wire random winding coil method has insufficient durability against high voltages. Instead, use a die winding coil method using rectangular rectangular copper wire. Is preferred. This die-wound coil system has already been adopted in the field of general high-power motors. The coil winding type stator winding is made by winding a rectangular copper wire with a rectangular cross section for the required number of turns, forming it into a turtle shell shape, winding it with insulating tape, and then placing it in the stator groove. Yes.

  However, when the stator winding of the die-wound coil system is arranged in the stator groove, since the stator winding cannot be deformed, the opening of the stator groove is the same as the groove bottom on the opposite side to the opening It needs to be wide. Therefore, the width of the opening of the stator groove is wider than that of the conventional semi-closed slot type.

  In the case of a canned motor, the pressure of the liquid filled in the can gap becomes a force that deforms the stator can in the radial direction, and if the width of the opening of the stator groove is wide, the stator can not enter the stator groove. Since deformation becomes large, there is a problem that cannot be used for applications where the pressure of the liquid is high.

  The present invention has been made in view of these points, and an object of the present invention is to provide a canned motor that can ensure the withstand voltage of the stator can.

The canned motor according to claim 1 is a cylindrical stator core provided with a stator groove having an opening opened on an inner peripheral surface thereof, and a stator winding disposed in the stator groove of the stator core. a stator having, a rotor which rotates inside of this stator, opposing surfaces of the stator and rotor in a canned motor covered respectively stator scan and rotor-scan, the the stator is provided in the stator grooves, and a stator winding fixed wedge for fixing the stator winding in said stator groove, provided in the opening portion of the stator groove, the stator A stator can support wedge for supporting the can, and the stator winding fixing wedge and the stator can support wedge are formed in the same cross-sectional shape .

  According to a second aspect of the present invention, in the canned motor according to the first aspect, a magnetic wedge is provided between the stator can and the stator can support wedge at the opening of the stator groove. It is what.

  The canned motor according to claim 3 is the canned motor according to claim 1 or 2, wherein the stator winding is a die-wound coil, and the stator groove is opposite to the opening from the opening. The groove width to the groove bottom on the side is formed to the same width.

  According to the can motor of claim 1, even if the pressure applied to the stator can is high by the stator can support wedge provided in the opening of the stator groove, the stator can is deformed into the stator groove. Can be secured and the withstand voltage of the stator can can be secured.

  According to the canned motor of the second aspect, in addition to the effect of the canned motor of the first aspect, the magnetic groove provided between the stator can and the stator can support wedge allows the opening of the stator groove to be opened. The increase in overcurrent loss can be suppressed.

  According to the canned motor of the third aspect, in addition to the effects of the canned motor of the first or second aspect, the stator winding is a die-wound coil, and the stator groove extends from the opening to the opening side. Even when the groove width to the opposite groove bottom is the same, and the width of the opening of the stator groove is wide, the withstand voltage of the stator can can be secured.

It is sectional drawing of a part of stator of the canned motor which shows one Embodiment. It is sectional drawing of the canned motor pump using a canned motor same as the above. It is sectional drawing of a part of stator same as the above.

  Hereinafter, an embodiment will be described with reference to the drawings.

  As shown in FIG. 2, reference numeral 11 denotes a canned motor pump. The canned motor pump 11 is configured by integrally connecting a canned motor 12 and a pump 13 in a liquid-tight manner.

  The canned motor 12 has a stator 17 formed by winding a stator winding 16 in a stator groove 15 of a cylindrical stator iron core 14, and the stator 17 is inserted into a stator frame 18. At the same time, a stator can 19 formed of a non-magnetic material such as stainless steel in a thin cylindrical shape is tightly inserted on the inner peripheral surface of the stator 17, and both end edges of the stator can 19 are liquidated to the stator frame 18. It is welded closely.

  Further, the canned motor 12 has a rotor 23 configured by attaching a rotor conductor 22 to a rotor groove 21 of a cylindrical rotor core 20, and the rotor 23 is inserted into a rotating shaft 24. A rotor can 25 formed of a non-magnetic material such as stainless steel and having a thin cylindrical shape is attached to the outer peripheral surface of the rotor 23.

  A rotor 23 is inserted inside the stator 17, and a stator can 19 of the stator 17 and a rotor can 25 of the rotor 23 are disposed to face each other with a can gap 26 interposed therebetween.

  Bearing frames 31 and 32 are attached to the stator frame 18 on the front side which is the pump 13 side and the rear side which is the opposite side, and are sliding bearings which rotatably support the rotating shaft 24 on these bearing boxes 31 and 32. Some bearings 33 and 34 are mounted. Sleeves 35 and 36 and thrust collars 37 and 38 for rotatably supporting the rotary shaft 24 are attached to the bearings 33 and 34, respectively.

  The pump 13 also has a casing 41 that is liquid-tightly attached to the stator frame 18 of the canned motor 12 and an impeller 42 that is attached to the rotary shaft 24 in the casing 41.

  In the canned motor pump 11, the rotor 23 is rotated by a rotational magnetic field generated by flowing an alternating current through the stator winding 16, and the impeller 42 rotates integrally with the rotor 23. During operation of the canned motor pump 11, a part of the pump handling liquid on the pump discharge side 41a of the casing 41 is led into the canned motor 12 through the circulation pipe 45, the rear bearing 34 is lubricated, and the stator can 19 rotates. The stator 17 and the rotor 23 are cooled by flowing into the can clearance 26 with the child can 25, and the front bearing 33 is lubricated, and then returned from the balance hole 42a of the impeller 42 to the pump suction side 41b of the casing 41. The structure to circulate is adopted.

  As shown in FIGS. 1 and 3, the stator core 14 is formed in a cylindrical shape by laminating magnetic steel plates provided with a plurality of stator grooves 15. The stator groove 15 has an opening 15a that opens on the inner peripheral surface of the stator core 14, and is a groove bottom on the opposite side of the opening 15a from the opening 15a, and is a stator winding housing 15b. Is formed in a rectangular shape having the same width.

  For the stator winding 16, a die winding coil is used. This die-wound coil stator winding 16 is formed by winding a rectangular copper wire 16a having a rectangular cross section for the required number of turns, forming a tortoiseshell shape, winding an insulating tape, and then forming a stator groove 15 The opening 15a is inserted into the stator winding housing 15b.

  On the side of the opening 15a of the stator groove 15, a stator winding fixing wedge 51 made of an insulating material for preventing the stator winding 16 from coming off is inserted and fixed from the axial direction of the stator core 14. Has been.

  Further, in the stator groove 15, the opening 15a side of the stator winding fixing wedge 51 is formed of an insulating material for supporting the stator can 19 that covers the inner peripheral surface of the stator core 14. The stator can support wedge 52 is inserted and fixed from the axial direction of the stator core 14, and is formed of a material having a high relative permeability between the stator can 19 and the stator can support wedge 52. A magnetic wedge 53 is arranged. The magnetic wedge 53 is disposed so as to cover the entire opening 15a, and the surface of the magnetic wedge 53 facing the stator can 19 may be formed as a curved surface corresponding to the outer peripheral surface of the stator can 19. It may be formed in a flat surface, and at least a portion that is substantially flush with the inner peripheral surface of the stator core 14 is sufficient. The stator can support wedge 52 and the magnetic wedge 53 are disposed in the stator groove 15 so as to be in close contact with each other, or are bonded together and fixed.

  In the canned motor pump 11 configured as described above, the pressure of the pump handling liquid filled in the can gap 26 acts to deform the stator can 19 in the outer diameter direction.

  In the portion of the inner peripheral surface of the stator core 14, the stator can 19 abuts on the stator core 14, and the deformation of the stator can 19 is restricted.

  In the portion of the stator groove 15 of the stator core 14, the stator can 19 abuts against the magnetic wedge 53 so that the stator can support wedge 52 supports the stator can 19 via the magnetic wedge 53. The deformation of the stator can 19 is restricted.

  Thus, even when the pressure applied to the stator can 19 is high due to the stator can support wedge 52 provided in the opening 15a of the stator groove 15, the stator can 19 is deformed into the stator groove 15. The pressure resistance of the stator can 19 can be secured by regulating.

  Moreover, the stator winding 16 is a die-coil, and the stator groove 15 has the same groove width from the opening 15a to the groove bottom opposite to the opening 15a. Even when the opening 15a of the groove 15 is wide, the withstand voltage of the stator can 19 can be ensured.

  Further, when the width of the opening 15a of the stator groove 15 is wide, the magnetic pulsation of the magnetic field in the direction of the rotating magnetic field increases, and the overcurrent loss in the stator can 19 near the opening 15a of the stator groove 15 is reduced. Although there is an increased problem, the overcurrent loss can be reduced by the magnetic wedge 53 provided between the stator can 19 and the stator can support wedge 52.

  As described above, the high-power canned motor 12 can be realized by ensuring the withstand voltage of the stator can 19 and further reducing the overcurrent loss in the stator can 19.

  In order to reduce the overcurrent loss, it is preferable to provide the magnetic wedge 53. However, the magnetic wedge 53 may be omitted, and the stator can 19 may be directly supported by the stator can support wedge 52.

  Further, the function of the stator winding fixing wedge 51 may be shared by the stator can support wedge 52, and the stator winding fixing wedge 51 may be omitted.

12 Canned motor
14 Stator core
15 Stator groove
15a opening
16 Stator winding
17 Stator
19 Stator can
23 Rotor
25 Rotor can
51 Wedge for fixing stator winding
52 Stator can support wedge
53 Magnetic wedge

Claims (3)

A stator having an inner circumferential surface stator winding stator groove having an opening which opening is disposed in the stator groove of a cylindrical stator core and the stator core provided, in this fixed A can motor that includes a rotor that rotates inside the rotor, and surfaces of the stator and the rotor that are opposed to each other are covered with the stator can and the rotor can, respectively.
The stator is
A stator winding fixing wedge provided in the stator groove for fixing the stator winding in the stator groove;
Provided in the opening portion of the stator grooves, and a stator scanning support wedge for supporting the stator scan,
The canned motor , wherein the stator winding fixing wedge and the stator can support wedge are formed in the same cross-sectional shape . The canned motor according to claim 1, wherein a magnetic wedge is provided between the stator can and the stator can support wedge at the opening of the stator groove. The stator winding is a die winding coil,
3. The canned motor according to claim 1, wherein the stator groove is formed to have the same width from the opening to the groove bottom on the side opposite to the opening.

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