JP2011066950A - Rotor for cage-type electric motor and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotor for a multiple type electric motor such as a dual cage-type electric motor, in which an inner bar is especially firmly fixed in an inner slot to prevent the inner bar from coming off. <P>SOLUTION: The rotor for the multiple cage-type electric motor includes a core 11, an inner bar 18 piercing through a slot 13 of the core 11, an outer bar 19 piercing through the slot 13 outside of a radius direction from the inner bar 18, an inner end ring 20 for connecting the sections from which the inner bar 18 protrudes from the end of diameter direction of a rotary shaft of the core 11 in a circumferential direction, and an outer end ring 21 for connecting the sections from which the outer bar 19 protrudes from the end of diameter direction of a rotary shaft of the core 11 in a circumferential direction. The inner bar 18 and the inner end ring 20 are fixed while they are pressed each other in a radius direction. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a rotor for a multi-cage motor such as a double-cage motor and a method for manufacturing the same, and more particularly to a feature of the inner bar fixing method.

  There is known a cage-type electric motor having a multiple cage type electric motor in which a rotor has an inner bar and an outer bar (Patent Document 1). In the rotor of the multi-cage motor, the inner bar and the outer bar penetrate through the iron core in which steel plates are laminated in the axial direction in the axial direction. Each steel plate is formed with a slot through which the inner bar and the outer bar pass.

JP-A-6-205570

  When manufacturing a rotor of a multi-cage motor, the inner bar and outer bar are accommodated in each slot and subjected to swaging by mechanical hitting from the outer peripheral side of each slot. The outer bar is fixed in the outer slot by narrowing. However, this swaging process cannot fix the inner bar to the inner slot.

  As a method for fixing the inner bar to the inner slot, a method using a varnish is known. However, fixing with a varnish does not have a sufficient fixing force, and the inner bar may come off.

  The present invention has been made in view of the above circumstances, and is a rotor of a multi-cage motor, in particular, to firmly fix the inner bar in the inner slot and prevent or suppress the inner bar from coming off. Objective.

  In order to achieve the above object, the rotor of the cage electric motor according to the present invention has a plurality of slots extending in the plane direction perpendicular to the rotation axis and extending in the radial direction from the outer periphery and spaced apart from each other in the circumferential direction. The steel plate 12 formed in this manner has a plurality of laminated iron cores in the rotation axis direction, an inner bar made of a conductive metal material that extends in the rotation axis direction through the slots of the plurality of laminated steel plates, and An outer bar made of a conductive metal material that extends through the slot of the steel plates laminated in a radial direction outside the inner bar in the rotation axis direction, and the inner bar protrudes from the end of the iron core in the rotation axis direction A cage-type electric motor comprising: an inner end ring that connects the parts that are circumferentially connected; and an outer end ring that connects the parts where the outer bar protrudes from the end in the rotational axis direction of the iron core in the circumferential direction. In the rotor, the slot includes an inner wide portion that accommodates the inner bar, an outer wide portion that accommodates the outer bar, and an intermediate narrow portion formed between the inner wide portion and the outer wide portion. And an outer narrow portion formed on the outer peripheral side of the outer wide portion, and the inner bar and the inner end ring are fixed in a state of being pressed against each other in the radial direction. .

  In the method of manufacturing a rotor of a cage motor according to the present invention, a plurality of slots extending in a plane direction perpendicular to the rotation axis and extending in the radial direction from the outer periphery are arranged at intervals in the circumferential direction. A plurality of stacked steel cores in the direction of the rotation axis, an inner bar made of a conductive metal material that extends through the slot of the stacked steel sheets in the direction of the rotation axis, and the plurality of sheets are stacked. An outer bar made of a conductive metal material that extends through the slot of the steel plate and extends radially outward from the inner bar in the direction of the rotation axis, and portions where the inner bar protrudes from the end in the rotation axis direction of the iron core. Manufacture of a rotor for a cage motor comprising an inner end ring connected in the circumferential direction and an outer end ring connecting the portions where the outer bar protrudes from the rotation axis direction end of the iron core in the circumferential direction The slot includes an inner wide portion that accommodates the inner bar, an outer wide portion that accommodates the outer bar, and an intermediate narrow portion formed between the inner wide portion and the outer wide portion. And an outer narrow portion formed on the outer peripheral side of the outer wide portion, and after the inner bar is disposed in the inner wide portion, the inner bar and the inner end ring are pressed against each other in the radial direction. The inner end ring is fitted into the inner bar so as to be fixed in a state, and the inner end ring is fixed to the inner bar.

  According to the present invention, in the rotor of the multi-cage motor, in particular, the inner bar can be firmly fixed in the inner slot, and the inner bar can be prevented or prevented from coming off.

It is a fragmentary sectional elevation view of the principal part of the upper half of the first embodiment of the rotor of the cage electric motor according to the present invention. It is the II-II arrow cross-sectional view of FIG. 1 and FIG. It is the fragmentary perspective view which looked at the upper part near the inner side end ring and outer side end ring of 1st Embodiment of the rotor of the cage motor of FIG. 1 from the outer side. It is the fragmentary perspective view which looked at the upper part near the inner side end ring and outer side end ring of 1st Embodiment of the rotor of the cage motor of FIG. 1 from the inner side. It is a fragmentary sectional elevation view of the principal part of the upper half of the second embodiment of the rotor of the cage motor according to the present invention.

  With reference to the drawings, an embodiment of a rotor of a cage motor according to the present invention will be described below.

[First Embodiment]
FIG. 1 is a partial cross-sectional elevational view of the main part of the upper half of the first embodiment of the rotor of the multi-cage motor according to the present invention, and FIG. 2 is a cross-sectional view taken along the line II-II in FIG. It is. FIG. 3 is a partial perspective view of the upper part in the vicinity of the inner end ring and the outer end ring of the first embodiment of the rotor of the cage motor shown in FIG. 1 as viewed from the outside. FIG. 4 is a partial perspective view of the rotor of the cage motor of FIG. 1 as viewed from the inside in the first embodiment in the vicinity of the inner end ring and the outer end ring.

  This embodiment is a rotor of a double cage motor. The iron core 11 is configured by stacking a plurality of steel plates 12 in the rotation axis direction. Each steel plate 12 has a plate shape extending perpendicular to the rotation axis, and is formed with a slot 13 extending radially inward from the outer periphery. A plurality of the slots 13 are arranged at intervals in the circumferential direction of the steel plate 12.

  An inner wide portion (inner slot portion) 14 is formed on the bottom portion of each slot 13, that is, the innermost diameter side, an intermediate narrow portion 15 is formed on the outer side, and an outer wide portion (outer side) is formed on the outer side. A slot portion 16 is formed, and an outer narrow portion 17 is formed at a position in contact with the outer periphery on the outer side. An inner bar 18 is accommodated in the inner wide portion 14, and an outer bar 19 is accommodated in the outer wide portion 16. The inner bar 18 and the outer bar 19 are made of a conductive material, for example, copper or aluminum, and extend in parallel to the rotation axis. The axial ends protrude from the ends of the iron core 11. The intermediate narrow portion 15 is narrower than the inner bar 18 and the outer bar 19. The width of the outer narrow portion 17 is narrower than the width of the outer bar 19. Further, the outer side of the outer narrow portion 17, that is, the outer peripheral portion of the slot 13, is processed so as to narrow the groove width by swaging and tighten the outer bar 19 in the outer narrow portion 17.

  In FIG. 2, the inner bar 18 and the outer bar 19 are shown narrowly for easy understanding of the structure. However, in practice, there is almost no gap between the inner wide portion 14 and the outer wide portion 16. ing.

  An annular inner end ring 20 that electrically connects the plurality of inner bars 18 in the circumferential direction is attached to the end of the inner bar 18. An annular outer end ring 21 that electrically connects the plurality of outer bars 19 in the circumferential direction is attached to the end of the outer bar 19. The inner end ring 20 and the outer end ring 21 are made of a conductive material such as copper.

  As shown in FIG. 1, a tapered surface 22 is formed so that the inner peripheral side near the tip of the inner bar 18 becomes narrower toward the tip, and the outer end surface of the inner end ring 20 is formed along the tapered surface 22. A tapered surface 23 is formed. In assembling the rotor, the inner end ring 20 is inserted from the tip of the inner bar 18 to the inner peripheral side and driven in the axial direction. Thereby, the tip of the inner bar 18 after completion is always urged toward the outer peripheral side. Thereby, the inner bar 18 is always pressed against the iron core 11, and the inner bar 18 can be fixed to the iron core 11 by a frictional force. Thereafter, the inner bar 18 and the inner end ring 20 may be fixed by welding or brazing.

  When fitting the inner end ring 20 to the inner bar 18, if the inner end ring 20 is cooled and the outer diameter is reduced by heat shrinkage and then the cold fitting is performed, the work is easy to perform and the original When the temperature returns, the inner end ring 20 expands and the contact between the inner end ring 20 and the inner bar 18 becomes stronger.

  Further, if the varnish is interposed between the inner wide portion 14 and the inner bar 18 of the slot 13 so that the inner bar 18 is fixed by the inner wide portion 14, the inner bar 18 can be further fixed.

[Second Embodiment]
FIG. 5 is a partial cross-sectional elevational view of the main part of the upper half of the second embodiment of the rotor of the multi-cage motor according to the present invention. The cross-sectional view taken along the line II-II in FIG. 5 is the same as FIG. Portions that are the same as or similar to those in the first embodiment are denoted by common reference numerals, and redundant description is omitted.

  In the second embodiment, as shown in FIG. 5, a tapered surface 24 is formed so that the outer side near the tip of the inner bar 18 becomes narrower toward the tip, and the inner side is formed along the tapered surface 24. A tapered surface 25 is formed on the inner peripheral surface of the end ring 20. In assembling the rotor, the inner end ring 20 is inserted from the tip of the inner bar 18 to the outer peripheral side and driven in the axial direction. Thereby, the end of the inner bar 18 after completion is always urged toward the inner peripheral side. Thereby, the inner bar 18 is always pressed against the iron core 11, and the inner bar 18 can be fixed to the iron core 11 by a frictional force. Thereafter, the inner bar 18 and the inner end ring 20 may be fixed by welding or brazing.

  When fitting the inner end ring 20 to the inner bar 18, if the inner end ring 20 is heated and shrink-fitted in a state where the outer diameter is increased due to thermal expansion, the work is easy to perform and the original When the temperature returns, the inner end ring 20 contracts, and the contact between the inner end ring 20 and the inner bar 18 becomes stronger.

  Further, if the varnish is interposed between the inner wide portion 14 and the inner bar 18 of the slot 13 so that the inner bar 18 is fixed by the inner wide portion 14, the inner bar 18 can be further fixed.

[Other Embodiments]
Each embodiment described above is merely an example, and the present invention is not limited thereto. For example, when performing cold fitting in the first embodiment or shrink fitting in the second embodiment, it is not essential to form the tapered surfaces 22, 23, 24, 25.

  In the above embodiment, the tapered surface is formed only on one of the inner bar 18 and the inner ring 20, but a tapered surface may be formed on both.

  Furthermore, although the case where the bar and the end ring are double was shown in the above embodiment, the present invention can be similarly applied even when the number of multiplexes is more than triple.

DESCRIPTION OF SYMBOLS 11 ... Iron core 12 ... Steel plate 13 ... Slot 14 ... Inner wide part (inner slot part)
15 ... Intermediate narrow part 16 ... Outer wide part (outer slot part)
17 ... Outer narrow portion 18 ... Inner bar 19 ... Outer bar 20 ... Inner end ring 21 ... Outer end rings 22, 23, 24, 25 ... Tapered surface

Claims (10)

A steel sheet 12 formed by laminating a plurality of slots extending in the plane direction perpendicular to the rotation axis and extending radially from the outer periphery at intervals in the circumferential direction, and a plurality of laminated steel cores in the rotation axis direction;
An inner bar made of a conductive metal material that extends through the slot of the laminated steel plates and extends in the rotation axis direction;
An outer bar made of a conductive metal material that extends through the slot of the laminated steel plates and extends in the direction of the rotation axis on the radially outer side of the inner bar; and
An inner end ring in which the inner bar connects portions protruding from the rotation axis direction end of the iron core in the circumferential direction;
An outer end ring for connecting the portions of the outer bar protruding from the rotation axis direction end of the iron core in the circumferential direction;
A rotor of a cage motor with
The slot includes an inner wide portion that accommodates the inner bar, an outer wide portion that accommodates the outer bar, an intermediate narrow portion formed between the inner wide portion and the outer wide portion, and the outer wide portion. And an outer narrow portion formed on the outer peripheral side of the
The inner bar and the inner end ring are fixed in a state of pressing against each other in the radial direction;
A cage-type electric motor rotor.   The basket according to claim 1, wherein the inner end ring is located radially inside the inner bar, and the inner end ring is fixed in a state of pushing the inner bar radially outward. Type motor rotor.   The basket according to claim 1, wherein the inner end ring is located radially outside the inner bar, and the inner end ring is fixed in a state in which the inner bar is radially compressed. Type motor rotor.   The rotor of a cage motor according to any one of claims 1 to 3, wherein the inner end ring is formed with a tapered surface on a surface in contact with the inner bar on the inner side in the axial direction. .   5. The cage-type electric motor according to claim 1, wherein a taper surface is formed on a surface in contact with the inner end ring near an axial end of the inner bar. Rotor.   The width of the outer narrow portion is narrowed by swaging after the outer bar is disposed in the outer wide portion. The rotor of a cage motor.   The rotor of a cage motor according to any one of claims 1 to 6, wherein a varnish is disposed between the outer wide portion and the outer bar. A steel sheet formed by laminating a plurality of slots extending in the plane direction perpendicular to the rotation axis and extending in the radial direction from the outer periphery and spaced apart from each other in the circumferential direction;
An inner bar made of a conductive metal material that extends through the slot of the laminated steel plates and extends in the rotation axis direction;
An outer bar made of a conductive metal material that extends through the slot of the laminated steel plates and extends in the direction of the rotation axis on the radially outer side of the inner bar; and
An inner end ring in which the inner bar connects portions protruding from the rotation axis direction end of the iron core in the circumferential direction;
An outer end ring for connecting the portions of the outer bar protruding from the rotation axis direction end of the iron core in the circumferential direction;
A method of manufacturing a rotor of a cage electric motor comprising:
The slot includes an inner wide portion that accommodates the inner bar, an outer wide portion that accommodates the outer bar, an intermediate narrow portion formed between the inner wide portion and the outer wide portion, and the outer wide portion. And an outer narrow portion formed on the outer peripheral side of the
After placing the inner bar in the inner wide part,
The inner end ring is fixed to the inner bar by fitting the inner end ring into the inner bar so that the inner bar and the inner end ring are fixed in a state of being pressed against each other in the radial direction. ,
A method for manufacturing a rotor of a cage motor.   The method for manufacturing a rotor of a cage motor according to claim 8, wherein when the inner end ring is fitted into the inner bar, the inner end ring is heated or cooled.   10. The cage-type electric motor according to claim 8, wherein when the inner end ring is fitted into the inner bar, the inner end ring is driven from an axial end portion of the inner end ring. A method for manufacturing a rotor.

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