JP4887990B2 - Stator heating method - Google Patents

Description

  The present invention relates to a stator in which a wire coil is mounted on a stator core that is a component of a motor. More specifically, the wire coil is fixed by filling and molding an insulating resin between the wire coils, and the wire coil The present invention relates to a stator heating method for heating the stator as pre-heating in a wire coil resin molding step for radiating heat, heating during molding, or heating after molding.

Conventionally, as a processing method for forming and fixing an electric wire coil to a stator having an electric wire coil mounted on a stator core, a varnish impregnation method in which the varnish is cured by impregnating the varnish between the electric wire coils and heating, A resin molding method in which an insulating resin is filled and molded between wire coils is performed by injection molding of a resin material using a wire.
And, as a method of impregnating the varnish into the electric wire coil, there are known a method of dripping and impregnating the varnish while rotating the stator, and an immersion method in which the lower part of the electric wire coil is immersed in the varnish tank and the varnish is impregnated by capillary action. ing. In any case, a preheating drying process for removing moisture and winding stress relaxation (annealing process) and a stator heating process for heating the wire coil to cure the thermosetting resin are required before and after the molding process. .
Similarly, in the resin molding method, since a thermosetting type resin is generally used, the resin is cured if the stator is not heated when the stator is inserted into the mold and insert injection molding is performed. If the resin is a thermoplastic type, if the stator is not heated, the fluidity of the resin will deteriorate significantly, causing problems such as unfilling. And a stator heating step in which the stator core is uniformly heated in advance within a certain temperature range. For example, examples of the thermosetting resin include unsaturated polyester, epoxy, PPS, and LCP resins.

The stator is composed of a stator core and an electric wire coil attached to the stator core. In particular, it is ideal that the entire electric wire coil is heated uniformly in a short time. At least, the temperature distribution of the entire wire coil needs to fall within a predetermined range in a short time.
However, since the wire coil is provided with an insulation coating and has an electrical terminal, it can be easily heated by energization, but the stator core has no insulation coating and is difficult to energize and has a large heat capacity and a short time. It is difficult to heat.
As a method for heating the stator core, Patent Document 1 discloses a method in which a wire coil is energized and energized and heated, and simultaneously, hot air is supplied into a drying furnace to heat the entire coil.
Further, Patent Documents 2 to 4 disclose that a 20 kHz high-frequency power is directly input to the electric wire coil, thereby energizing and heating the electric wire coil and simultaneously induction heating the stator core.

JP 2004-096876 A JP 2005-102404 A JP 2005-086954 A JP 2005-110493 A

However, the conventional stator heating method has the following problems.
That is, in the method of Patent Document 1, since the stator core is heated with hot air, there is a problem that several hours are required to heat the stator core to a predetermined temperature. In particular, since the heat of the electric wire coil that is energized and heated is taken away by the stator core, there is a problem that significant temperature variation occurs between the electric wire coils or between the portions, or the electric wire coil temperature is made uniform by eliminating the variation. Because of this, there was a problem that required a long curing time.
Similarly, in the methods of Patent Document 2 to Patent Document 4, by directly supplying high-frequency power to the wire coil, the wire coil self-heats, and at the same time, a magnetic field is generated via the wire coil. By utilizing the fact that eddy current is generated and heated near the inner surface of the stator core located on the surface in contact with the coil, the entire wire coil including the slot portion can be heated.
However, since the electric heating of the electric wire coil and the dielectric heating of the stator core are performed with the same high frequency power that supplies electric current to the electric wire coil, the heating of the electric wire coil and the heating of the stator core can be performed only at the same timing. Also, because it can always be performed only with the same electric power, the stator core with a large heat capacity has a shortage of power due to insufficient power, heat is taken away from the wire coil to the stator core, the temperature of the wire coil decreases, and the wire coil The large variation in temperature between these parts was still a problem. Specifically, there is a temperature variation between the portions of the wire coil such that the temperature of the wire coil in the slot portion of the stator core is 60 ° C. to 100 ° C. lower than the wire coil at the coil end.

If the temperature variation between the parts of the wire coil is large, in the case of varnish, the varnish impregnated between the wire coils partially gels at a very high temperature and the fluidity becomes poor. In some cases, the permeation flow is partially lost, and the gap between the wire coils cannot be filled uniformly in a short time. Alternatively, a difference in varnish temperature occurs depending on the temperature level, a difference in viscosity occurs depending on the part, and the sagging drop is worsened when the surface tension is reduced.
Similarly, in the case of the resin mold, if the temperature is too high, the reaction is accelerated, gelation is caused to stop flowing, the viscosity is lowered, and burrs appear.

  This invention is made | formed in view of the said situation, The objective is to provide the stator heating method with few temperature variations in the site | part in an electric wire coil in a short time.

In order to achieve the above object, the stator heating method of the present invention employs the following method.
(1) An electric wire for fixing a wire coil by filling and molding an insulating resin between the wire coils to a stator having a wire coil mounted on a stator core, and for radiating heat of the wire coil A stator heating method for heating the stator as pre-heating in the coil resin molding step, heating during molding, or heating after molding, wherein the heating of the electric wire coil and induction heating of the stator core Are performed independently.
(2) Of the inner diameter induction heating coil facing the inner peripheral surface of the center portion of the stator core described in (1) or the outer diameter induction heating core facing the outer peripheral surface of the stator core, at least One is provided.

(3) In the coil heating method described in (1) or (2), the stator core is configured by a laminated plate, and the induction heating coil that performs the induction heating is opposed to a central portion in the lamination direction of the laminated plate. By making the coil density at the position lower than the coil density at the position facing the end portion of the laminated plate, the center portion in the laminating direction of the laminated plate is given less heat than both end portions.
(4) In the coil heating method described in (2) or (3), the induction heating coil protrudes a predetermined distance from both ends of the stator core.

(5) In the stator heating method described in (1), the induction heating is performed prior to the energization heating in terms of time.
(6) In the stator heating method described in (5), after the induction heating is started, the energization heating is started when the stator core reaches a predetermined temperature or when a predetermined time has elapsed. It is characterized by doing.
(7) In the stator heating method described in (5), when the stator core reaches a temperature of 1/5 to 2/3 of the annealing temperature (internal stress relaxation temperature) of the wire coil, The energization heating is started.

The effect | action and effect of the stator heating method which has the said process are demonstrated.
According to the stator heating method described in (1), since the electric heating for the electric wire coil and the induction heating for the stator core are performed with different electric powers, optimum heating for the electric wire coil and the stator core, respectively. Conditions can be given. In particular, the temperature variation between the wire coil parts, the temperature variation between the wire coil and the stator core, and the stator core is formed by laminating the plate material. If it occurs at the initial stage of the process, it takes a long time to correct the generated temperature variation. Therefore, from the initial stage, it is necessary to heat each of the wire coil and the stator core so as not to cause temperature variations between the wire coil portions and the like as much as possible.

In the method (1) or (2) in which the stator core is directly heated, either or both of the inner diameter induction heating coil and the outer diameter induction heating coil are used. Heat can be applied from the inner end and the outer end.
In particular, heating time can be further shortened by heating from both sides. Specifically, as compared with the case where only one induction heating coil is used, the use of both induction heating coils can increase the heating rate by 1.5 times. In particular, when the difference between the inner and outer diameters of the stator core exceeds 50 mm, the heating time becomes longer due to the longer distance of heat transfer in the plate with only one side, so induction heating from both sides The effect is great.
In addition to increasing the heating rate, heat is not dissipated from the opposite end compared to heating from only one side, and heating from both sides also reduces temperature variations within the plate. it can.

Moreover, since the laminated plate which laminated | stacked the flat plate is used as a stator core, between a flat plate in a coating layer and an air layer tends to heat-insulate, and heat transfer is bad. On the other hand, since heat is taken away by heat radiation at the upper and lower end surfaces of the hollow cylindrical stator core, the temperature of the central portion in the stacking direction of the stacked flat plates becomes high, and temperature variation occurs in the stacking direction. There's a problem. According to the method of (3), since the coil density at the position facing the end of the laminated plate is larger than the coil density at the position facing the central portion of the laminated plate, Much heat can be applied, and variations in the temperature of the stator core in the stacking direction can be reduced.
Furthermore, according to the method (4), more heat can be applied to the end portion of the laminated plate, so that the temperature variation between the end portion and the central portion of the laminated plate is reduced, and the overall temperature of the stator core is reduced. Can be made more uniform.

In addition, according to the method (1), since the electric heating to the electric wire coil and the induction heating to the stator core can be performed at different timings, optimum heating for the electric wire coil and the stator core, respectively. Conditions can be given.
In particular, since the heat capacity of the stator core is larger than the heat capacity of the wire coil, in the wire coil in the slot portion surrounded by the stator core having a large heat capacity, the stator core is first heated by induction to the wire coil. If the stator coil has already reached a certain temperature when the current is heated, it is possible to prevent heat from being removed from the wire coil to the stator core. The overall heating time can be greatly shortened.

When induction heating of the stator core is preceded, the timing of starting energization heating to the wire coil may be performed after the elapse of a predetermined time. In particular, the temperature of the stator core in the slot portion where the wire coil is densely measured is measured. The energization heating may be started when the stator core reaches a predetermined temperature.
It is necessary to relieve (anneal) the internal stress that remains inside when the wire coil is attached to the stator core or when the wire is manufactured. In order to perform annealing in a short time, for example, there is a method of heating to 150 ° C. or more and annealing in 10 to 60 seconds.
In order to efficiently heat the electric wire coil to a predetermined temperature of 150 ° C. to 200 ° C., the temperature of the stator core is 1 of a predetermined temperature of 150 ° C. to 200 ° C. by dielectric heating to the stator core. When the temperature reaches / 5 to 2/3, it is preferable to start energization heating to the wire coil.
When the electric wire coil is heated to 250 ° C. or higher, the enamel layer may be damaged. Therefore, for example, heating is stopped at a temperature of 200 ° C. or lower. On the other hand, under the annealing conditions described above, the annealing temperature for the wire coil needs to raise the temperature of all the portions of the wire coil by 150 ° C. or more.
To uniformly heat the wire coil to the annealing temperature in a short time, by starting the energization heating to the wire coil when the stator core is heated to a predetermined temperature by dielectric heating to the stator core, It can be achieved for the first time.

A first example of a stator heating method according to an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a sectional view showing a general stator winding distribution (distributed winding) configuration and a stator heating device. The hollow stator core 11 is configured by laminating silicon steel (steel-based) flat plates having a magnetic permeability of about 600 to 1200. A plurality of slot shapes are formed on the inner surface of the hollow stator core 11. A winding coil 12 is wound around each set of slots. In the figure, the central portion of the winding coil 12 is hidden by the stator core 11 and only the winding coil end appears.
As a manufacturing process of the motor, varnish impregnation treatment or resin molding is performed on the stator. In any case, the winding coil and the stator core constituting the stator, especially the winding, are used. It is desirable to heat the coil uniformly.

In FIG. 1, the lower surface of the stator core 11 is supported by an insulating holder 15. An inner diameter induction heating coil 14 is installed inside the stator core 11 along the hollow surface of the stator core 11. An outer diameter induction heating coil 13 is installed on the outer side of the stator core 11 along the outer peripheral surface of the stator core 11.
The inner diameter induction heating coil 14 and the outer diameter induction heating coil 13 are respectively adjusted and supplied in a power range of 45 KHz, 200 V, and 20 KW by a high frequency power supply circuit (not shown). In this embodiment, the high frequency supplied to the induction heating coil is 45 KHz, but the high frequency supplied to the induction heating coil may be in the range of 10 to 100 KHz.
The terminal-attached portion 12 a of the winding coil 12 is connected to the energization heating terminal 17 by a terminal presser 16. The energization heating terminal 17 is adjusted and supplied in a power range of 200 V and 60 KW by an energization power supply circuit (not shown).
As described above, in this embodiment, since the power to the induction heating coil and the power for energization heating are supplied independently, the power is supplied to the inner diameter induction heating coil 14 and the outer diameter induction heating coil 13. The optimum power can be selected such that the induction heating power is a high frequency power of 20 KW and the energization heating power to be passed through the winding coil 12 is 60 KW power.

Next, the operation of the heating device of FIG. 1 will be described. The winding coil 12 is made of copper, and copper has a magnetic permeability close to 1, so that it is not heated effectively in principle. On the other hand, the stator core 11 is configured by laminating silicon steel (steel-based) flat plates having a magnetic permeability of about 600 to 1200, and thus is effectively heated in principle.
When a high frequency power is applied to the inner diameter induction heating coil 14, a magnetic field is generated, and an eddy current is generated in a portion on the inner peripheral side of the flat plate on which the stator core 11 is laminated, thereby generating heat. Since a coating layer and an air layer exist between the laminated flat plates, the heat transfer between the flat plates is poor and the heat transfer is poor. In the flat plate, it is gradually heated outward and the temperature is raised.
Similarly, when a high frequency power is applied to the outer diameter induction heating coil 13, a magnetic field is generated, and an eddy current is generated in the outer peripheral portion of the flat plate on which the stator core 11 is laminated, thereby generating heat. Since a coating layer and an air layer exist between the laminated flat plates, the heat transfer between the flat plates is poor and the heat transfer is poor. In the flat plate, it is gradually heated inward and heated.
On the other hand, the winding coil 12 is self-heated by applying electric power for energization heating, and the whole is likely to be heated almost uniformly.
Thus, the inner diameter induction heating coil 14 and the outer diameter induction heating coil 13 heat only the stator core 11 directly, and the energization heating heats only the direct winding coil 12. However, the winding coil 12 and the stator core 11 naturally have a heat transfer relationship.

The temperature rise of the stator core 11 and the winding coil 12 is shown in FIG. The horizontal axis is time (seconds), and the vertical axis is temperature. The dotted lines A1 and A2 indicate the temperature rise curves of the winding coil 12. A dotted line A <b> 1 is a portion showing the highest temperature in the entire region of the winding coil 12. A dotted line A <b> 2 is a part indicating the lowest temperature in the entire area of the winding coil 12.
The solid line shows the temperature rise curve of the stator core 11. The solid lines B1 and B2 indicate the temperature rise curves of the stator core 11. A solid line B <b> 1 is a portion showing the highest temperature in the entire region of the stator core 11. A solid line B <b> 2 is a portion showing the lowest temperature in the entire region of the stator core 11.

As shown in FIG. 4, in the energization heating, since the energization heating current is directly applied to the winding coil 12, the average temperature of the winding coil 12 rises to around 150 ° C. in a short time of 10 seconds or less. In this embodiment, energization is stopped when the average temperature of the winding coil 12 exceeds 150 ° C. The winding coil 12 is enamel-coated, but if the winding coil 12 exceeds 250 ° C., the enamel layer may be damaged. Therefore, A1 which is the highest temperature in the entire area of the winding coil 12 is safe. This is to avoid exceeding 200 ° C. in consideration.
In this embodiment, since the power to the induction heating coil and the power for energization heating are supplied independently, the supply of the power for energization heating is stopped regardless of the power supply to the induction heating coil. be able to.
On the other hand, since the induction heating is performed by generating an eddy current in the stator core 11 and heating only the inside near the surface of the stator core 11, it takes time to gradually transfer the heat further to the inside. It takes 40 seconds or more to reach 150 ° C. When the average temperature of the stator core 11 exceeds 150 ° C., the application of the high frequency power to the inner diameter induction heating coil 14 and the outer diameter induction heating coil 13 is stopped.

Looking at the overall temperature change, since it takes time until the stator core 11 is heated, the heat of the portion of the winding coil 12 that is in close contact with or close to the stator core 11 is applied to the stator core 11. The temperature is lowered and the temperature difference across the winding coil 12 is increased.
In this embodiment, since the stator core 11 is simultaneously induction-heated with the inner diameter induction heating coil 14 and the outer diameter induction heating coil 13, the stator core 11 is gradually heated. Since heat taken from the winding coil 12 to the stator core 11 is reduced, temperature variation in the entire region of the winding coil 12 is reduced. And after the average temperature of the stator core 11 exceeds 150 degreeC and induction heating is also stopped, heat | fever falls gradually. Then, with soaking and curing for several minutes after 96 seconds, both the winding coil 12 and the stator core 11 are close to the average temperature of 120 ° C., and the temperature variation between them is reduced, and the target value of 120 ° C. ± 5 Enter the range of ℃.
In soaking, the variation can be reduced a little. Soaking and curing may be performed in a heat-insulated space that is thermally shielded, or in winter and the like, may be performed in a heat-insulated space that is slightly heated.

  As described above in detail, according to the stator heating method of the first embodiment, insulating resin is applied between the winding coils 12 with respect to the stator in which the winding coils 12 are wound around the stator core 11. The stator is heated as the pre-heating of the wire coil resin molding step for fixing the winding coil 12 by filling molding and radiating the heat of the wire coil, heating during molding, or heating after molding. A stator heating method, in which energization heating to the winding coil 12 and induction heating to the stator core 11 are performed independently, so that the power to be applied and the timing to turn on / off the application are arbitrarily set In addition, since it is possible to control the energization heating for the winding coil 12 and the induction heating for the stator core 11 with optimum power and optimum on / off timing, respectively, the heating time can be greatly shortened. The temperature variation in the part and the temperature variation in the winding coil 12 can be reduced.

Next, second and third embodiments will be described. FIG. 2 shows a second embodiment in which the stator core 11 is induction-heated only by the inner diameter type induction heating coil 14 without installing the outer diameter type induction heating coil 13. FIG. 3 shows a third embodiment in which the stator core 11 is induction heated only by the outer diameter induction heating coil 13 without installing the inner diameter induction heating coil 14.
The operation when only one of the inner diameter induction heating coil 14 and the outer diameter induction heating coil 13 is used as in the second or third embodiment will be described with reference to FIG. .
The meanings of dotted lines A1 and A2 and solid lines B1 and B2 in FIG. 5 are the same as those in FIG. Since there is only one induction heating coil, the temperature rise of the stator core 11 is considerably moderate as compared with FIG. The average temperature of the stator core 11 exceeding 150 ° C. takes 90 seconds after the start of heating and takes more time than the first embodiment, but can be dealt with in a significantly shorter time than the conventional method.
It is. The induction heating is stopped when the average temperature of the stator core 11 exceeds 150 ° C., as in FIG. The electric heating is the same as in FIG.
In the second and third embodiments, the curing time can be within the target temperature range of 120 ° C. ± 5 ° C. by taking more time than the first embodiment.

  According to the first to third embodiments, the inner diameter induction heating coil 14 facing the hollow surface of the stator core 11 or the outer diameter induction heating core 13 facing the outer peripheral surface of the stator core 11, Since at least one is provided, the stator core 11 can be efficiently heated. In particular, when the stator core 11 is formed by laminating flat plates, even if heat transfer between the flat plates is poor, each flat plate can be heated from the inner peripheral surface and the outer peripheral surface. Can be heated.

Next, a fourth embodiment will be described with reference to FIG. Here, the diameter of the induction heating coil is 8 mm. For example, the outer diameter type induction heating coil 13 has a lower coil density at the center h2 than both ends as shown in the figure. . Similarly, as shown in the drawing, the inner diameter induction heating coil 14 has a lower coil density at the center h1 than at both ends. Thereby, since the central part can generate less induced current than both ends, heating of the central part can be further suppressed at both ends.
Further, the outer diameter induction heating coil 13 and the inner diameter induction heating coil 14 protrude from the end of the stator core 11 by a predetermined distance.
As a result, the induced current generated by the protruding induction coil acts on both ends of the stator core more greatly, so that both ends of the stator core can be heated more than the center.
In the present embodiment, it has been experimentally confirmed that the predetermined amount of protrusion is effective from 1 mm to 16 mm.

The operational effects of the fourth embodiment are shown in FIG. The contents of the figure are almost the same as those in FIG. 4 is different from FIG. 4 in that the widths of the solid lines B1 and B2 indicating the temperature variation of the stator core are smaller.
By heating more both ends with respect to the central portion, it is possible to reduce variations in temperature that normally occur due to heat radiation from both ends.
On the other hand, since the heat of the central portion of the stator core 11 is higher than that of the both end portions, the variation can be similarly reduced by heating the central portion of the stator core 11 less.

According to the fourth embodiment, the stator core 11 is formed of a laminated plate, and the induction heating coils 13 and 14 that perform induction heating have a higher density than the coil density at the position facing the center of the laminated plate. Since the coil density at the positions facing both end portions is large, more heat is applied to both end portions than to the center portion of the laminated plate. Therefore, even if heat is radiated from the end face of the stator core 11, the stator core 11 Since both end portions are heated more than the central portion, temperature variations at both end portions and the central portion can be reduced.
In addition, since the induction heating coil protrudes from the both ends of the stator core 11 by a predetermined distance, both ends of the stator core 11 can be heated more. Therefore, the temperature of the end portion and the center portion of the stator core 11 can be increased. Variations can be reduced.
On the other hand, since the heat of the central portion of the stator core 11 is higher than that of the both end portions, the variation can be similarly reduced by heating the central portion of the stator core 11 less.

Next, a fifth embodiment will be described with reference to FIG. The configuration of the apparatus of the fifth embodiment is the same as that of FIG. Since only the control method is different, the control method will be described.
That is, first, only the inner diameter type induction coil 14 and the outer diameter type induction coil 13 are energized without causing the winding coil 12 to pass an energization heating current. As a result, only the temperatures B1 and B2 of the stator core 11 rise. Then, when the average temperature of the stator core 11 becomes a predetermined temperature within a range of 1/5 to 2/3 of the predetermined temperature TM exceeding the annealing temperature of 150 ° C. as an annealing condition, for example. Then, energization of the energization heating current is started. This is the timing indicated by T in the figure. Since the stator core 11 has already been warmed, when the winding coil 12 is heated, less heat is taken away from the winding coil 12 by the stator core 11, so that the winding coil 12 can be annealed at a short time. It is heated to a certain 150 ° C., and the temperature variation of the winding coil 12 can be reduced.
In this embodiment, the energization timing of the energization heating current is measured by measuring the temperature of the stator core 11. However, if the stator has a constant shape, it may be controlled only by the passage of time.

  Although the energization heating current is stopped at an appropriate time when the winding coil 12 exceeds the annealing temperature, since the heating by the induction current to the stator core 11 is continued, the temperature of the winding coil 12 is The annealing temperature can be maintained for a predetermined time W without rapidly decreasing. Heating by induction current to the stator core 11 is stopped after 60 seconds. As a result, both the stator core 11 and the winding coil 12 decrease in temperature, and the temperature decreases to within the target temperature by soaking for several minutes after 96 seconds. The difference between A1 and A2, which is the temperature variation of the winding coil 12, and the difference between B1 and B2, which is the temperature variation of the stator core, are controlled so as to be a small difference due to temperature rise. The temperature of the coil 12 and the stator core 11 can be set within the target value at the shortest. However, the heating time on the equipment can be as short as about 60 seconds.

According to the fifth embodiment, since induction heating is performed temporally prior to energization heating, when energization heating is started on the winding coil 12, the stator core 11 has already been wound. Since the coil core 12 is heated to a temperature higher than that of the wire coil 12 and less heat is taken away from the winding coil 12 by the stator core 11, when the winding coil 12 is heated, temperature variation due to the portion of the winding coil 12 is reduced. can do.
In particular, after the induction heating is started, when the stator core reaches a predetermined temperature or when a predetermined time has elapsed, the energization heating is started. Since the temperature can be set in accordance with the temperature state of the stator core 11 corresponding to the stator, the temperature variation due to the portion of the winding coil 12 of the various types of stators can be reduced.

In addition, when the stator core 11 reaches 1/5 or more and 2/3 or less of the annealing temperature of the winding coil 12, energization heating is started. Since the temperature variation due to the part can be reduced, the temperature of the highest part can be kept low even if the lowest part of the winding coil 12 exceeds, for example, the annealing condition of this time of 150 ° C. The residual stress in all parts of the wound coil 12 can be stably removed while reducing the risk of damage to the coating.
Conventionally, it is necessary to ensure that the annealing temperature is heated by maintaining the temperature of the lowest part of the winding coil 12 for a predetermined time, and even if the furnace has a large variation or a constant temperature. In order to guarantee the lower limit temperature and reduce the heating time, it was often performed in a separate process at about 100 ° C. for several tens of minutes.
However, according to the present embodiment, since the heating of the winding coil 12 can be accurately controlled, the heating as the pretreatment heating can be performed in a short time, so that the annealing at 1.5 times the conventional temperature can be performed. Since heating can be performed simultaneously, the total number of steps can be shortened and performed in a short time.

In addition, this invention is not limited to each said embodiment, It can also implement by changing a part of structure suitably in the range which does not deviate from the meaning of invention.
For example, in this embodiment, the target temperature is 120 ° C. plus or minus 5 ° C., but the numerical value of 120 ° C. is a matter determined by the size of the coil, the molding method, the type of varnish, etc. It is to be decided. However, the range of plus or minus 5 ° C. is a numerical value that can be adopted as a substantially sufficient range regardless of which molding method is employed.
In addition, in the present embodiment, induction and energization are performed only once each on and off in the present embodiment, but heating may be performed in several times, or induction heating may be performed during energization heating. May be stopped.
In this embodiment, 150 ° C. is adopted as the annealing temperature, but the annealing temperature is also determined by the coil diameter of the winding coil, the size of the coil, and the like.
In this embodiment, the stator uses a general winding distributed winding form as the electric wire coil. However, a concentrated winding form or a cassette type coil form is used. May be.
Moreover, although the electromagnetic steel plate lamination | stacking form was demonstrated in the present Example as a stator core, you may use cases, such as a block shape formed into a compact.

It is sectional drawing of the stator heating apparatus of 1st Example of this invention. It is a data figure which shows the temperature rise with the time passage of the stator core 11 and the electric wire coil 12 in 1st Example. It is sectional drawing of the stator heating apparatus of 2nd Example of this invention. It is sectional drawing of the stator heating apparatus of 3rd Example of this invention. It is a data figure which shows the temperature rise with the time passage of the stator core 11 and the electric wire coil 12 in a 2nd and 3rd Example. It is sectional drawing of the coil heating apparatus of 4th Example of this invention. It is a data figure which shows the temperature rise with the time passage of the stator core 11 and the electric wire coil 12 in 4th Example. It is a data figure which shows the temperature rise with the time passage of the stator core 11 and the electric wire coil 12 in 5th Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Stator core 12 Winding coil 13 Outer diameter type induction heating coil 14 Inner diameter type induction heating coil

Claims (5)

Electric wire coil resin molding for fixing the electric wire coil by filling and molding the insulating resin between the electric wire coils to the stator having the electric wire coil mounted on the stator core, and for radiating the heat of the electric wire coil. In the stator heating method of heating the stator as pre-heating of the process, or heating during molding, or heating after molding,
Conducting heating to the wire coil and induction heating to the stator core are performed independently,
Performing the induction heating in advance of the energization heating in time;
When the stator core is heated to a predetermined temperature by the induction heating, the current heating is started, and the current heating and the induction heating are performed in parallel, so that the wire coil is transferred to the stator core. The heat taken away is reduced, and the variation between the temperature of the wire coil and the temperature of the stator core is reduced,
Stator heating method characterized by the above. In the stator heating method according to claim 1,
The stator heating method, wherein the predetermined temperature is not less than 1/5 and not more than 2/3 of the annealing temperature of the wire coil. In the stator heating method according to claim 1 or 2,
At least one of an inner diameter induction heating coil facing the inner peripheral surface of the center portion of the stator core or an outer diameter induction heating core facing the outer peripheral surface of the stator core is provided. Stator heating method. In any one of the stator heating methods according to claim 1 to claim 3,
The stator core is constituted by a laminated plate;
With respect to the induction heating coil that performs the induction heating, the coil density at the position facing the central portion in the stacking direction of the laminate is made lower than the coil density at the position facing the end of the laminate, The stator heating method, wherein the center portion in the stacking direction is given less heat than both ends. In the stator heating method according to claim 3 or 4,
The stator heating method, wherein the induction heating coil protrudes a predetermined distance from both ends of the stator core.

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