JP5874747B2 - Rotor core heating device and rotor core shrink fitting method - Google Patents

Description

  The present invention relates to a technology of a rotor core heating device and a rotor core shrink fitting method.

  The rotor core is a component of the motor. The motor is rotatably held in a sealed case and has a rotor integrally formed at one end thereof, a rotor core fitted on the shaft, and a fixed rotor on the sealed case side. And a stator opposed to the outer peripheral surface of the stator with a predetermined gap.

  In order to manufacture the motor, it is necessary to externally fit the rotor core to the shaft. A shrink fitting method is known as a method for externally fitting the rotor core. In shrink fitting of the rotor core to the shaft, the rotor core is heated by a rotor core heating device, and the heated rotor core is cooled after being fitted to the shaft.

  For example, Patent Document 1 discloses that a first heater that performs high-frequency heating (IH (Induction Heating) heating) on the inner peripheral side surface of a hollow cylindrical rotor core and an outer peripheral side surface of the hollow cylindrical rotor core by IH A rotor core heating device including a second heater for heating is disclosed.

A configuration of a conventional rotor core heating apparatus 500 represented by Patent Document 1 will be described with reference to FIGS. 5 (A) and 5 (B).
5A and 5B schematically show the configuration of a conventional rotor core heating device 500 in a cross-sectional view. In the following, description will be given according to the axial directions shown in FIGS. 5 (A) and 5 (B).

  The rotor core heating device 500 is a device that heats the rotor core 550 by IH in order to shrink-fit the rotor core 550 to a shaft (not shown). The rotor core heating device 500 includes an inner diameter coil 510, an outer diameter coil 520, and an IH heater (not shown).

  The rotor core 550 is formed in a columnar shape, and a hollow portion 560 is formed in the axial direction (see FIG. 5A). The rotor core 550 is configured by laminating a plurality of steel plates.

  The inner diameter coil 510 is formed in a spiral shape and is arranged on the inner peripheral side (hollow portion 560) of the rotor core 550. The inner diameter coil 510 is arranged in the hollow portion 560 so as to draw a spiral toward the axial direction.

  The outer diameter coil 520 is formed in a spiral shape and is disposed on the outer peripheral side of the rotor core 550. The outer diameter coil 520 is arranged so as to draw a spiral around the outer periphery of the rotor core 550 in the axial direction.

  The IH heater causes an alternating current to flow through the inner diameter coil 510 and the outer diameter coil 520 and generates magnetic lines of force around the inner diameter coil 510 and the outer diameter coil 520.

  5A shows the rotor core 550 in which the axial length of the rotor core 550 and the axial lengths of the inner diameter coil 510 and the outer diameter coil 520 are substantially the same. FIG. 5B shows a rotor core 580 in which the axial length of the rotor core 550 is shorter than the axial lengths of the inner diameter coil 510 and the outer diameter coil 520.

The operation of the conventional rotor core heating apparatus 500 will be described with reference to FIG.
In addition, in FIG. 6, the effect | action of the conventional rotor core heating apparatus 500 is typically represented by sectional view. FIG. 6 shows a rotor core 580 in which the axial length of the rotor core is shorter than the axial lengths of the inner diameter coil 510 and the outer diameter coil 520.

  When magnetic lines of force are generated around the inner diameter coil 510 and the outer diameter coil 520, the rotor core 580 disposed in the vicinity is affected by the lines of magnetic force, and an eddy current flows in the rotor core 580. Since the rotor core 580 has an electrical resistance, when a current flows through the rotor core 580, Joule heat is generated and the rotor core 580 self-heats.

  As described above, FIG. 6 shows the rotor core 580 in which the axial length of the rotor core is shorter than the axial lengths of the inner diameter coil 510 and the outer diameter coil 520. When the rotor core 580 is affected by the lines of magnetic force, the magnetic flux concentrates on the upper end surface in the axial direction of the rotor core 580 (point C in FIG. 6), and the steel plate located at the upper end portion of the rotor core 580 is turned up due to abnormal heat generation. May occur.

  For example, when turning occurs in one steel plate, the turning of the steel plate insulates heat transfer with other steel plates, so that the turning becomes larger and reaches the plastic region, and the rotor core 580 is deformed. There is a case.

  Therefore, conventionally, it is necessary to prepare a dedicated rotor core heating device corresponding to the axial length of the rotor core, which increases the cost of equipment. Therefore, a highly versatile rotor core heating device that can cope with the difference in the axial length of the rotor core is desired.

Japanese Patent Application Laid-Open No. 07-022168

  The problem to be solved by the present invention is to provide a rotor core heating device and a rotor core shrink-fitting method that can cope with differences in the axial length of the rotor core.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, in claim 1, a rotor core heating device that heats an inner peripheral side surface and an outer peripheral side surface of a hollow cylindrical rotor core with a coil at a high frequency, and is arranged with a gap provided on one side end surface in the axial direction of the rotor core, A magnetic flux shielding jig having a sectional view substantially the same as the axial sectional shape of the outer shape of the rotor core is provided so as to face the one end face, and the magnetic flux shielding jig includes an inner portion of the rotor core during high-frequency heating. It is provided in the position which overlaps in the axial direction of the coil arrange | positioned at a surrounding side surface, and the said rotor core .

  The rotor core heating device according to claim 1, wherein the magnetic flux shielding jig is disposed with a gap so as to face both side end surfaces in the axial direction of the rotor core, and the inner peripheral side surface of the rotor core The coil arranged at is arranged such that both ends of the coil in the axial direction protrude from the rotor core with respect to the rotor core.

  According to a third aspect of the present invention, in the rotor core heating device according to the first or second aspect, the magnetic flux shielding jig is made of copper.

  In Claim 4, it is a rotor core shrink fitting method which shrink-fits and fastens a rotor core to a shaft, Comprising: Heating the internal diameter of a rotor core using the rotor core heating apparatus as described in any one of Claim 1 thru | or 3. The shaft is shrink-fitted and fastened to the rotor core whose diameter is expanded and the inner diameter is expanded.

  According to the rotor core heating device and the rotor core shrink-fitting method of the present invention, it is possible to cope with the difference in the axial length of the rotor core.

The schematic diagram which showed the structure of the rotor core heating apparatus of 1st embodiment. The schematic diagram which showed the effect | action of the rotor core heating apparatus of 1st embodiment. The schematic diagram which showed the structure of the rotor core heating apparatus of 2nd embodiment. The schematic diagram which showed the effect | action of the rotor core heating apparatus of 2nd embodiment. The schematic diagram which showed the structure of the conventional rotor core heating apparatus. The schematic diagram which showed the effect | action of the conventional rotor core heating apparatus.

[First embodiment]
The configuration of the rotor core heating device 100 will be described with reference to FIG.
In addition, in FIG. 1, the structure of the rotor core heating apparatus 100 is typically represented by the cross sectional view. In the following, description will be given according to the axial direction shown in FIG.

  The rotor core heating device 100 is a first embodiment according to the rotor core heating device of the present invention. The rotor core heating apparatus 100 is an apparatus that heats the rotor core 150 by IH (Induction Heating) in order to shrink-fit the rotor core 150 to a shaft (not shown).

  The rotor core 150 is a component of a motor (not shown). The motor includes a shaft (not shown) in which a roller is rotatably held in a sealed case (not shown) and a roller is integrally formed at one end, and a rotor core 150 fitted on the shaft. And a stator (not shown) which is fixed to the sealing case and faces the outer peripheral surface of the rotor with a predetermined gap.

  In order to manufacture the motor, it is necessary to externally fit the rotor core 150 to the shaft. A shrink fitting method is known as a method for externally fitting the rotor core 150. In the shrink fitting of the rotor core 150 to the shaft, the rotor core 150 is heated by the rotor core heating apparatus 100, and the heated rotor core 150 is cooled after being fitted to the shaft.

  The rotor core heating device 100 includes an inner diameter coil 110, an outer diameter coil 120, an IH heater (not shown), and a magnetic flux shielding jig 170. The rotor core 150 is formed in a cylindrical shape, and a hollow portion 160 is formed in the axial direction. The rotor core 150 is configured by laminating a plurality of steel plates.

  The inner diameter coil 110 is formed in a spiral shape, and is disposed on the inner peripheral side (hollow portion 160) of the rotor core 150. The inner diameter coil 110 is arranged in the hollow portion 160 so as to draw a spiral in the axial direction.

  The outer diameter coil 120 is formed in a spiral shape and is disposed on the outer peripheral side of the rotor core 150. The outer diameter coil 120 is arranged so as to draw a spiral around the outer periphery of the rotor core 150 in the axial direction.

  The IH heater causes an alternating current to flow through the inner diameter coil 110 and the outer diameter coil 120 to generate lines of magnetic force around the inner diameter coil 110 and the outer diameter coil 120.

  The magnetic flux shielding jig 170 is formed in a cylindrical shape, and a hollow portion 180 is formed in the axial direction. The magnetic flux shielding jig 170 is made of copper. The sectional view shape in the axial direction of the magnetic flux shielding jig 170 is substantially the same as the sectional view shape of the rotor core 150.

  When the rotor core 150 is heated by the rotor core heating device 100, the magnetic flux shielding jig 170 is disposed on the upper side in the axial direction of the rotor core 150. The magnetic flux shielding jig 170 is arranged with a gap without being in close contact with the rotor core 150. In the present embodiment, the sum of the axial length of the magnetic flux shielding jig 170 and the axial length of the rotor core 150 is substantially the same as the axial length of the inner diameter coil 110 and the outer diameter coil 120. .

  The axial lengths of the inner diameter coil 110 and the outer diameter coil 120 are preferably substantially the same as the longest axial length of the rotor core that is supposed to be heated.

  Further, magnetic flux concentrates on the inner peripheral side of the axial end surface of the rotor core 150, and abnormal heat generation is likely to occur. On the other hand, the outer peripheral side of the axial end surface of the rotor core 150 is less likely to generate abnormal heat due to the concentration of magnetic flux than the inner peripheral side. Therefore, although the outer shape of the magnetic flux shielding jig 170 is substantially the same as the outer shape of the rotor core 150, the outer diameter of the magnetic flux shielding jig 170 may be larger than the outer diameter of the rotor core 150.

The operation of the rotor core heating device 100 will be described with reference to FIG.
In addition, in FIG. 2, the effect | action of the rotor core heating apparatus 100 is typically represented by sectional view.

When magnetic lines of force are generated around the inner diameter coil 110 and the outer diameter coil 120, the rotor core 150 disposed in the vicinity is affected by the lines of magnetic force, and an eddy current flows in the rotor core 150.
Since the rotor core 150 has electrical resistance, when current flows through the rotor core 150, Joule heat is generated and the rotor core 150 self-heats.

  At this time, since the magnetic flux shielding jig 170 is disposed on the upper side in the axial direction of the rotor core 150, the magnetic flux is prevented from concentrating on the upper end surface in the axial direction of the rotor core 150. The magnetic flux is distributed as if the axial length of the rotor core 150 is substantially the same as the axial lengths of the inner diameter coil 110 and the outer diameter coil 120.

  Therefore, the magnetic flux does not concentrate on the upper end surface in the axial direction of the rotor core 150 (point A in FIG. 2), and it is possible to prevent the steel sheet from being turned up due to abnormal heat generation.

The effect of the rotor core heating device 100 will be described.
In the rotor core heating apparatus 100, the axial length of the rotor core 150 is prepared by preparing a plurality of magnetic flux shielding jigs 170 corresponding to the axial height of the rotor core 150 corresponding to the axial height of the rotor core 150. Can handle the difference.

  That is, the set of the inner diameter coil 110 and the outer diameter coil 120 is obtained by adding the axial length of the magnetic flux shielding jig 170 and the axial length of the rotor core 150 to the inner diameter coil 110 and the outer diameter coil 120. By preparing a plurality of magnetic flux shielding jigs 170 so as to be substantially the same as the length in the axial direction, it is possible to cope with the difference in the axial length of the rotor core.

  In the present embodiment, the magnetic flux shielding jig 170 is made of copper, but is not limited to this. For example, if the substance has magnetism such as iron, the same effect as the present invention can be obtained.

  In the present embodiment, the sum of the axial length of the magnetic flux shielding jig 170 and the axial length of the rotor core 150 is substantially the same as the axial length of the inner diameter coil 110 and the outer diameter coil 120. However, it is not limited to this.

  Even if the sum of the axial length of the magnetic flux shielding jig 170 and the axial length of the rotor core 150 is longer than the axial length of the inner diameter coil 110 and the outer diameter coil 120, or the magnetic flux shielding Even if the sum of the axial length of the jig 170 and the axial length of the rotor core 150 is shorter than the axial lengths of the inner diameter coil 110 and the outer diameter coil 120, the same effect as the present invention is achieved. Has an effect.

[Second Embodiment]
The configuration of the rotor core heating device 200 will be described with reference to FIG.
In addition, in FIG. 3, the structure of the rotor core heating apparatus 200 is typically represented by the cross sectional view. In the following, description will be given according to the axial direction shown in FIG.

  The rotor core heating device 200 is a second embodiment according to the rotor core heating device of the present invention. The rotor core heating apparatus 200 is an apparatus that heats the rotor core 250 by IH (Induction Heating) in order to shrink-fit the rotor core 250 to a shaft (not shown).

  The rotor core 250 is a component of a motor (not shown). The motor is rotatably held in a sealed case (not shown) and has a shaft (not shown) in which a roller is integrally formed at one end, and a rotor core 250 fitted on the shaft. And a stator (not shown) which is fixed to the sealing case and faces the outer peripheral surface of the rotor with a predetermined gap.

  In order to manufacture the motor, it is necessary to externally fit the rotor core 250 to the shaft. A shrink fitting method is known as a method for externally fitting the rotor core 250. In the shrink fitting of the rotor core 250 to the shaft, the rotor core 250 is heated by the rotor core heating device 200, and the heated rotor core 250 is cooled after being fitted to the shaft.

  The rotor core heating apparatus 200 includes an inner diameter coil 210, an outer diameter coil 220, an IH heater (not shown), and a magnetic flux shielding jig 270. The rotor core 250 is formed in a cylindrical shape, and a hollow portion 260 is formed in the axial direction. The rotor core 250 is configured by laminating a plurality of steel plates.

  The inner diameter coil 210 is formed in a spiral shape and is disposed on the inner peripheral side (hollow portion 260) of the rotor core 250. The inner diameter coil 210 is arranged in the hollow portion 260 so as to draw a spiral in the axial direction. The axial length of the inner diameter coil 210 is longer than the axial length of the rotor core 250.

  The inner diameter coil 210 is disposed so that the upper and lower ends in the axial direction of the inner diameter coil 210 protrude from the rotor core 250 with respect to the rotor core 250. More specifically, the inner diameter coil 210 is preferably disposed at a position where the central portion of the inner diameter coil 210 and the central portion of the rotor core 250 substantially coincide with each other in the axial direction.

  The outer diameter coil 220 is formed in a spiral shape and is disposed on the outer peripheral side of the rotor core 250. The outer diameter coil 220 is disposed so as to draw a spiral around the outer periphery of the rotor core 250 in the axial direction.

  The IH heater causes an alternating current to flow through the inner diameter coil 210 and the outer diameter coil 220 and generates magnetic lines of force around the inner diameter coil 210 and the outer diameter coil 220.

  The magnetic flux shielding jig 270 is formed in a cylindrical shape, and a hollow portion 280 is formed in the axial direction. The magnetic flux shielding jig 270 is made of copper. The sectional view shape in the axial direction of the magnetic flux shielding jig 270 is substantially the same as the sectional view shape of the rotor core 250.

  The magnetic flux shielding jig 270 is disposed on the upper and lower sides of the rotor core 250 in the axial direction when the rotor core 250 is heated by the rotor core heating device 200. Each magnetic flux shielding jig 270 is disposed with a gap without being in close contact with the rotor core 250.

  Moreover, magnetic flux concentrates on the inner peripheral side of the axial end surface of the rotor core 250, and abnormal heat generation is likely to occur. On the other hand, the outer peripheral side of the axial end surface of the rotor core 250 is less likely to generate abnormal heat due to the concentration of magnetic flux than the inner peripheral side. Therefore, although the outer shape of the magnetic flux shielding jig 270 is substantially the same as the outer shape of the rotor core 250, the outer diameter of the magnetic flux shielding jig 270 may be larger than the outer diameter of the rotor core 250.

The operation of the rotor core heating device 200 will be described with reference to FIG.
In FIG. 4, the action of the rotor core heating device 200 is schematically shown in a sectional view.

  When magnetic lines of force are generated around the inner diameter coil 210 and the outer diameter coil 220, the rotor core 250 disposed in the vicinity is affected by the lines of magnetic force, and an eddy current flows in the rotor core 250. Since the rotor core 250 has electrical resistance, when current flows through the rotor core 250, Joule heat is generated and the rotor core 250 self-heats.

  At this time, since the magnetic flux shielding jig 270 is disposed on the upper and lower sides in the axial direction of the rotor core 250, the magnetic flux is prevented from concentrating on the upper or lower end surface in the axial direction of the rotor core 250. The magnetic flux is substantially the same as if the axial length of the magnetic flux shielding jig 270 arranged on the upper side of the rotor core 250 and the axial length of the magnetic flux shielding jig 270 arranged on the lower side are added. Distributed as if.

  Therefore, the magnetic flux does not concentrate on the upper end surface and the lower end surface in the axial direction of the rotor core 150 (point B in FIG. 4), and it is possible to prevent the steel sheet from being turned up due to abnormal heat generation. Further, since the magnetic flux shielding jig 270 is disposed on the upper and lower sides of the rotor core 250 in the axial direction, the rotor core 250 generates a uniform magnetic field in the axial direction, and the rotor core 250 is heated uniformly in the axial direction. The inner diameter of the rotor core 250 is uniformly expanded.

The effect of the rotor core heating device 200 will be described.
The rotor core heating device 200 can cope with the difference in the axial length of the rotor core 250. That is, if the rotor core 250 has an axial length shorter than the axial length of the inner diameter coil 210 with respect to the set of inner diameter coil 210 and outer diameter coil 220, a magnetic flux shielding jig is provided above and below the rotor core 250. By disposing 270, the difference in the axial length of the rotor core 250 can be accommodated.

  Further, in the rotor core heating device 200, the magnetic flux shielding jig 270 is arranged on the upper side and the lower side in the axial direction of the rotor core 250, so that in the axial direction of the rotor core 250 compared to the rotor core heating device 100 of the first embodiment. A uniform magnetic field is generated, the rotor core 250 is heated uniformly in the axial direction, and the inner diameter of the rotor core 250 can be expanded uniformly.

  In this embodiment, the magnetic flux shielding jig 270 is made of copper, but is not limited to this. For example, if the substance has magnetism such as iron, the same effect as the present invention can be obtained.

The rotor core shrink fitting method S300 will be described.
The rotor core shrink fitting method S300 is an embodiment according to the rotor core shrink fitting method of the present invention. In the rotor core shrink fitting method S300, the rotor core 150 or the rotor core 250 is heated using the rotor core heating device 100 or the rotor core heating device 200 to expand the inner diameter, and the shaft is shrink fitted to the rotor core 150 or the rotor core 250 having the expanded inner diameter. And fasten.

DESCRIPTION OF SYMBOLS 100 Rotor core heating apparatus 110 Inner diameter coil 120 Outer diameter coil 150 Rotor core 160 Hollow part 170 Magnetic flux shielding jig 200 Rotor core heating apparatus 210 Inner diameter coil 220 Outer diameter coil 250 Rotor core 260 Hollow part 270 Magnetic flux shielding jig 500 Conventional rotor core heating apparatus

Claims (4)

A rotor core heating device for high-frequency heating the inner peripheral side surface and outer peripheral side surface of a hollow cylindrical rotor core with a coil,
A magnetic flux shielding jig having a cross-sectional view shape substantially the same as the axial cross-sectional view shape of the outer shape of the rotor core is disposed so as to have a gap on one end surface in the axial direction of the rotor core and facing the one end surface. Prepared ,
The magnetic flux shielding jig is provided at a position overlapping with the coil disposed on the inner peripheral side surface of the rotor core and the axial direction of the rotor core during high-frequency heating.
Rotor core heating device. The rotor core heating device according to claim 1,
The magnetic flux shielding jig is disposed with a gap so as to face both end faces in the axial direction of the rotor core,
The coil disposed on the inner peripheral side surface of the rotor core is disposed such that both ends of the coil in the axial direction protrude from the rotor core with respect to the rotor core.
Rotor core heating device. In the rotor core heating device according to claim 1 or 2,
The magnetic flux shielding jig is made of copper,
Rotor core heating device. A rotor core shrink fitting method in which a rotor core is shrink fitted on a shaft and fastened.
The rotor core heating device according to any one of claims 1 to 3 is used to heat and expand the inner diameter of the rotor core,
The shaft is shrink-fitted and fastened to the rotor core whose inner diameter is expanded,
Rotor core shrink fitting method.

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