JP4727552B2 - Stator coil and core heating apparatus and heating method - Google Patents

Description

  The present invention relates to a heating apparatus and a heating method for heating a coil and a core of a stator used for an automobile generator or the like prior to a varnish impregnation step or the like.

  Generally, when manufacturing this type of stator, the stator coil wound on the inner peripheral side of the annular core is impregnated with varnish or resin-molded. Prior to this varnish-impregnation step or resin mold, the stator coil And the core needs to be heated.

  Conventionally, prior to varnish impregnation or resin molding, the stator is placed in a heating furnace to heat the entire stator coil.

  However, in the above-described conventional technique, an operator has to insert the stator into the heating furnace, and after heating, the stator must be taken out of the heating furnace and sent to the next process, resulting in poor working efficiency and a long heating time. Accordingly, the amount of power used is increased accordingly.

  In addition, it takes time to take out the stator coil heated to a predetermined temperature from the heating furnace and transport it to the next process, and it is difficult to keep the stator coil at the predetermined temperature. As a result, the varnish applied to the stator coil is well impregnated. There is a problem that the quality of the resin molded product is impaired due to difficulty or cracks.

  Therefore, for the purpose of improving work efficiency and reducing power consumption by reducing heating time, a coil head for high frequency induction heating is disposed in the hollow portion of the annular core, and the stator coil and the core are rapidly heated by the high frequency induction heating method. Has been proposed.

In addition to heating by a high frequency induction heating method, it has also been proposed to heat the stator coil more uniformly by energizing the stator coil to self-heat the coil (for example, Patent Document 1).
JP 60-82050 A

  However, in the method in which the coil head for high frequency induction heating is arranged in the hollow portion of the annular core and the stator coil and the core are heated by the high frequency induction heating method, most of the magnetic flux generated from the coil head for high frequency induction heating is Acts on the end in the thickness direction. Since the core is usually composed of a laminated body of silicon steel sheets, the thermal conductivity in the thickness direction of the core is not good, so only this part is locally heated and thermally deformed. In addition, there is a problem that the coil is not sufficiently heated.

  In addition to the heating by the high frequency induction heating method, the method of heating the core and the stator coil by energizing the stator coil to self-heat the stator coil causes the self-heating temperature to vary by the stator coil, There is a problem in that electromagnetic force is generated during energization and the entire stator coil vibrates. Furthermore, there are problems that positioning of the terminals for energization is difficult and automation is difficult, or sparks are generated between the connection terminals due to poor connection when the stator coil and the power supply for energization are connected.

  The present invention has been made in view of the above circumstances, and can prevent the temperature rise due to local heating of the core by the high frequency induction heating method without energizing the stator coil, and the coil and the core. It is an object of the present invention to provide a stator coil and core heating apparatus and a heating method that can uniformly heat the coil.

The above problem is solved by the following means.
The hollow portion of the wound on an annular core into the inner peripheral side (1) stator coils, by high-frequency induction heating coil head is inserted, provided with a high-frequency induction heating means for heating the stator coil and the core, the The coil head for high frequency induction heating has an annular winding portion corresponding to the vicinity of the stator coil on at least one of the one end side and the other end side excluding the intermediate portion in the thickness direction of the core. The high frequency induction heating means is further arranged coaxially with the core at a position outside the core in the thickness direction , and prevents the magnetic flux generated from the coil head from reaching the outer periphery of the core. A stator coil and core heating apparatus, comprising a shield.
(2) The stator coil and core heating device according to item 1 above, wherein the shield is cylindrical or donut-shaped.
(3) The stator coil and core heating device according to (1) or (2), wherein the shield is disposed in the vicinity of the outer end of the stator coil in the radial direction of the core.
(4) The stator coil and the core according to any one of the preceding items 1 to 3, wherein an outer coil head for high-frequency induction heating is disposed around an outer peripheral portion of the core and positioned in an intermediate portion in the thickness direction of the core. Heating device.
(5) A stator coil and core heating method in which a high frequency induction heating coil head is inserted into a hollow portion of an annular core in which a stator coil is wound on the inner peripheral side, and the stator coil is heated by high frequency induction, The high frequency induction heating coil head has an annular winding portion corresponding to the vicinity of the stator coil on at least one end side of one end side and the other end side excluding an intermediate portion in the thickness direction of the core. And a shield that prevents the magnetic flux generated from the high frequency induction heating coil head from reaching the outer periphery of the core is disposed coaxially with the core at a position outside the core in the thickness direction. A method for heating a stator coil and a core, wherein an AC voltage is applied to the coil head to heat the stator coil and the core.
(6) The method for heating a stator coil and a core according to item 5 above, wherein the shield is cylindrical or donut-shaped.
(7) The method for heating a stator coil according to (5) or (6), wherein the shielding body is disposed in the vicinity of an outer end portion of the stator coil in a radial direction of the core.
(8) The stator according to any one of 5 to 7 above, in which the outer periphery of the core is surrounded and an outer coil head for high-frequency induction heating positioned at an intermediate portion in the thickness direction of the core is disposed to perform high-frequency induction heating. Coil and core heating method.

According to the invention described in (1) above , the magnetic flux generated from the coil head for high-frequency induction heating reaches the outer periphery of the core at the outer position in the thickness direction of the core and coaxially with the core. Since the magnetic body generated by the high frequency induction heating device coil head is prevented from reaching the outer periphery of the core, heating from the inner periphery becomes the mainstream, while the stator coil The high frequency magnetic flux is transmitted and the stator coil is sufficiently heated. For this reason, only the end portion in the thickness direction of the outer peripheral portion of the core is locally heated, and the stator coil and the core can be uniformly heated while eliminating the inconvenience of causing thermal deformation and damage to the insulating resin. . Of course, since there is no energization of the stator coil, variations in the heat generation temperature of the stator coil due to energization, vibration of the stator coil, difficulty in positioning the terminals during energization, sparking due to poor connection during energization connection, etc. There is no inconvenience. In addition, the high frequency induction heating coil head has an annular winding portion corresponding to the vicinity of the stator coil on at least one of the one end side and the other end side excluding the intermediate portion in the thickness direction of the core. Therefore, compared with the case where the winding part of the coil head is provided only in the central part in the thickness direction of the core, the high-frequency magnetic flux from both winding parts by the coil head is effectively transmitted to the stator coil. And heating can be performed more efficiently.

  According to the invention described in item (2), the cylindrical or donut-shaped shield can effectively prevent the magnetic flux generated by the coil head of the high-frequency induction heating device from reaching the outer periphery of the core.

  According to the invention described in item (3) above, since the shield is disposed near the outer end of the stator coil in the radial direction of the core, the magnetic flux generated by the coil head reaches the outer periphery of the core. Can be more reliably prevented, and it can be heated uniformly from the inner periphery by heat conduction of each laminated core.

According to the invention described in item (4) above, the outer coil head for high-frequency induction heating is disposed around the outer periphery of the core and located in the middle in the thickness direction of the core. As a result, the stator coil and the core are induction-heated. For this reason, induction heating from both the inner and outer sides requires less heating time until the temperature of the core and the stator coil rises, compared to heating using only the inner coil head, and less energy is required for heating, reducing power consumption. Become.

According to the invention described in item (5) , the cylindrical or donut-shaped shield can effectively prevent the magnetic flux generated by the high frequency induction heating device coil head from reaching the outer peripheral portion of the core.

According to the invention described in item (6) above, the cylindrical or donut-shaped shield can effectively suppress the magnetic flux generated in the coil head of the high-frequency induction heating device from reaching the outer peripheral portion of the core.

According to the invention described in item (7) , since the shield is arranged near the outer end of the stator coil in the radial direction of the core, the magnetic flux generated by the coil head reaches the outer periphery of the core. Can be more reliably prevented.

According to the invention described in the preceding item (8) , the outer periphery of the core is surrounded, the outer coil head for high-frequency induction heating located at the intermediate portion in the thickness direction of the core is disposed, and high-frequency induction heating is performed. The stator coil and the core are also induction-heated by this outer coil head, and the heating time until the temperature of the core and the stator coil rises is less than that by heating only by the inner coil head. Less energy is required.

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

  1 and 2 are a schematic plan view and a front view showing a stator manufacturing system including a stator coil and a core heating device according to an embodiment of the present invention, respectively.

  1 and 2, the stator coil and core heating device applies the varnish W (FIG. 9) to the coil (stator coil) L of the stator M shown in FIGS. 3 and 4. Used to heat the core F.

  As shown in FIGS. 3 and 4, the stator M has a stator coil L wound around an inner peripheral projection Fb of an annular core F formed by laminating a number of steel plates in the thickness direction. Is provided with a three-phase external terminal T.

  The stator manufacturing system generally includes high-frequency induction heating that performs high-frequency induction heating on the stator coil L and the core F of the stator M at a predetermined position, the main work table 1, the transfer mechanism 2 for transferring the stator M, and the stator M. A heating device 3 and varnish applying means 4 for the stator M are provided.

  The main work table 1 is formed, for example, in a rectangular shape having a planar shape that is long in the left-right direction, and the upper surface side of the main work table 1 is spaced from the right side by a predetermined interval, a loading area S1, a heating area S2, and a varnish application area S3. Is set as a carry-out area S4.

  The transfer mechanism 2 grips the stator M from above the main work table 1 and transports it from the loading area S1 to the unloading area S4 through the areas S2 and S3.

  The transfer mechanism 2 is supported by, for example, support columns 2 a and 2 a, and a rail 21 disposed along the left-right direction at a position above the main work table portion 1, and can be moved in the left-right direction by the rail 21. The trolley 23 is supported, and the chuck device 24 is suspended from the trolley 23 via a wire 23a so as to be lifted and lowered. The chuck 24a in the chuck device 24 grips the stator M. ing.

  Of course, the transfer mechanism 2 of the stator M is not limited to the one using the rails 21 and the trolley 23, and various transport mechanisms can be adopted, and a self-propelled robot or the like may be used.

  The high frequency induction heating device 3 is for heating and holding the stator coil L of the stator M, particularly the stator coil L, at a predetermined temperature prior to varnishing the stator coil L of the stator M. For example, the high frequency induction unit 31 A receiving table 32 for the stator M transferred to the heating region S2, a heating coil head 33 drawn from the high-frequency oscillation unit 31 via the cable 34, and the coil head 33 inserted into the stator M. A coil head setting mechanism 35 and a cylindrical shield 36 are provided.

  The high frequency induction heating device 3 can set heating conditions such as a heating temperature and a heating time according to the type of the stator M via an operation panel (not shown). Various set heating conditions are stored in a storage unit (not shown) as a heating chart. Then, according to the type of stator M to be processed, the corresponding heating chart is selected / instructed on the operation panel or the like to pop out the heating chart, and by computer control, the condition of the stator M is adjusted based on the heating chart. Heating conditions are to be implemented.

  A plurality of support pins (not shown) are erected on the upper surface of the receiving table 32, and when the stator M is placed on the receiving table 32, the support is inserted into a plurality of mounting holes (not shown) in the stator M. The stator M is positioned by being inserted into the pin.

  Of course, the receiving table 32 is not essential, and the stator M may be received directly on the work table 1.

  As shown in FIG. 5, the heating coil head 33 has a two-stage configuration of an upper winding portion 33 a and a lower winding portion 33 b in the thickness direction (vertical direction) of the core F. The portion 33a is set to correspond to substantially the upper end portion of the stator coil L on one end side (upper end side) in the thickness direction of the core F, for example, by two turns, and the lower winding portion 33b is, for example, two turns The other end side (lower end side) in the thickness direction of the core F is set so as to correspond to the substantially lower end portion of the stator coil L.

  In this way, the heating coil head 33 corresponds to the upper winding portion 33a corresponding to the vicinity of the upper end of the stator coil L on one end side in the thickness direction of the core F, and to the vicinity of the lower end of the stator coil L on the other end side. The reason why the lower winding portion 33b is provided is to allow the high-frequency magnetic flux generated in the winding portions 33a and 33b to effectively act and transmit to the stator coil L of the stator M from near.

  The heating coil head 33 is not limited to the two stages of the upper winding part 33a and the lower winding part 33b, and may have at least one winding part 33a (33b). . Further, the number of turns in each of the winding portions 33a and 33b may be set to 3 times, 1 time, or other multiple times depending on a desired coil heating rate.

  The coil head setting mechanism 35 includes, for example, a coil head holding member 351 that holds the coil head 33 on the lower side, and a cylinder 352 that drives the coil head holding member 351 up and down, and the stator M receives the receiving base 32. The piston rod 352a is extended and the coil head 33 is inserted into the central hole Ma of the stator M.

  The coil head setting mechanism 35 is not limited to the one having the above-described configuration, and an arbitrary configuration such as one in which the coil head 33 is inserted into the stator M from above can be adopted.

  In this embodiment, the cylindrical shield 36 has a cylindrical shape and attempts to act on the outer peripheral portion Fa of the core F so as to concentrate and transmit the induced magnetic flux generated by the coil head 33 to the stator coil L. The magnetic flux to be shielded is guided to the stator coil L, arranged coaxially with the core F, and near the outer end of the stator coil L in the radial direction of the core F. It is arranged on the upper and lower outer sides of the stator coil L in the vertical direction. It is desirable that the gap between the stator coil L and each cylindrical shield 36 be set within about 5 mm because the magnetic flux can act on the stator coil L more effectively.

  The constituent material of the shield 36 may be a metal material, and is preferably a metal material with low magnetic resistance, such as a Cu plate. It is possible to use not only flat plates but also punching metals and mesh materials.

  The cylindrical shield 36 may be cooled by a cooling device (not shown) in order to suppress heat generation due to a current flowing in the circumferential direction. Moreover, in this example, as shown in FIG. 6, the slit 36a is provided in a part of the cylindrical shield 36 in the circumferential direction, and the eddy current in the circumferential direction is cut off to thereby prevent the cylindrical shield 36 itself. It is supposed to prevent heat generation. In addition, when the cooling device is provided, the slit 36a can be omitted.

  The varnish applying means 5 is for applying the varnish W (FIG. 9) to the stator coil L of the stator M that has been heated by the high frequency induction heating and then transferred to the varnish application region S3. A receiving table 41 for receiving the stator M, a varnish supply unit 42 disposed behind the work table unit 1, and a varnish supply pipe 43 connected from the varnish supply unit 42 via the varnish supply pipe 43. A varnish application gun 44 for application is provided.

  Of course, the receiving table 41 is not essential, and the heated stator M may be received directly on the work table 1.

  Next, a method for manufacturing the stator M by the manufacturing system having the above configuration will be described.

  First, when the stator M that has undergone the previous process is carried into the carry-in area S1 on the work table 1, the stator M is gripped by the chuck 24a of the chuck device 24 as shown in FIG. As the trolley 23 moves to the left, the stator M gripped by the chuck 24a is transferred to the heating region S2.

  When the stator M reaches the heating region S2, the stator M gripped by the chuck 24 is received and positioned by the receiving table 32 as shown in FIG. 7B.

  In this state, the cylinder 351 in the coil head setting mechanism 35 is driven, and the piston rod 352a extends as shown in FIG. 8C, so that the coil head 33 moves up and down together with the coil head holding member 351, It is set by being inserted into the central hole Ma of the stator M.

  In this state, first, when the high-frequency oscillation unit 31 in the high-frequency induction heating device 3 is driven, a high-frequency output is applied to the coil head 33. An induction effect is exerted, and the stator coil L is directly heated. Furthermore, the inner peripheral protrusion Fb of the core F is also heated by the high frequency induction action, whereby the stator coil L is heated via the core F.

  As for the heating conditions, a heating chart corresponding to the stator M may be selected from various heating charts stored in advance in the storage unit of the high-frequency induction heating device 3 using an operation panel or the like.

  When the stator coil L of the stator M is heated to a certain temperature by the high frequency induction heating by the coil head 33, the high frequency induction heating by the coil head 33 is stopped.

  Next, the piston rod 351 in the cylinder 352 is contracted to disengage the coil head 33 from the central hole Ma of the stator M.

  Thereafter, as shown in FIG. 8D, the stator M is gripped by the chuck 24a in the chuck device 24, transferred to the varnish application region S3, and placed on the receiving table 41 for positioning.

  If the varnish supply unit 42 is driven in this state, the varnish W is applied to the stator coil L of the stator M from the varnish application gun 4 positioned above the stator M, as shown in FIG. L is impregnated with varnish W.

  Thus, in applying the varnish, the stator coil L is heated directly and further through the core F by induction heating of the stator M by the high frequency induction heating coil head 33, so that a heating furnace is used. As in the case, there is no need to put the stator M in and out of the heating furnace, and workability is improved. Of course, after high-frequency induction heating of the stator M, the stator M is put in a heating furnace to prevent cooling, and then varnish application may be performed.

  By the way, when the stator M is induction-heated by the high-frequency induction heating coil head 33, if the cylindrical shields 36 are not provided, most of the high-frequency magnetic flux from the coil head 33 is the outer peripheral portion of the core F. In particular, it acts on the end portion Fa in the thickness direction, and there is a possibility that only this portion is locally heated.

  On the other hand, in this embodiment, since the cylindrical shields 36 are provided on the upper and lower outer sides of the stator coil L in the thickness direction of the core F, the outer peripheral portion Fa of the core F from the coil head 33 is provided. The shielding effect by the cylindrical shields 36 and 36 acts on the high-frequency magnetic flux that is to act on, and is prevented from acting on the outer peripheral portion Fa of the core F, so that a lot of high-frequency magnetic flux is induced to the stator coil L. The Accordingly, the outer peripheral portion Fa of the core F is not locally heated, and the stator coil L is efficiently and quickly heated.

  Moreover, since the cylindrical shield 36 is disposed in the vicinity of the outer end of the stator coil L in the radial direction of the core F, the high-frequency magnetic flux can be more effectively transmitted through the stator coil L. .

  FIG. 10 shows another embodiment of the present invention.

  In the embodiment shown in FIG. 10, a substantially central portion in the thickness direction of the stator M is surrounded, for example, a one-turn core heating outer coil head 50 is provided.

  By providing such an outer coil head 50, the core F is heated by high frequency induction heating from the outside, and the stator coil L is also heated via the core F that has been heated by this heating. The whole can be heated more efficiently, and compared with the case where only the coil head 33 is used for heating, the heating time required for the stator coil L and the core F to rise to a predetermined temperature is reduced, and heating is possible. The energy required can be reduced and the power can be reduced.

  In order to perform more efficient heating, it is desirable that heating is first performed by the inner coil head 33 and then heating is started by the outer heating head 50. The inner coil head 33 and the outer coil head 50 may be connected to the same high frequency power source, and the heating timing and power may be adjusted, or may be driven by different power sources.

  Incidentally, while using the coil head 33 shown in FIG. 5, the copper cylindrical shield 36 (outer diameter 203 mm, height 70 mm, thickness 3 mm) shown in FIG. When the outer peripheral surface is arranged on the upper and lower outer sides of the stator coil L in the thickness direction of the core F so as to be flush with the outer end portion of the stator coil L in the radial direction of the core F (the stator coil L and each cylinder) The high-frequency induction heating was performed under the same conditions except for the shield 36 in the case where the gap with the shape shield 36 was 10 mm) and the case where the shield 36 was not disposed. The input power was 10 kw (180 V, 56 A), and the frequency was 44.1 kHz.

  As a result, when the cylindrical shield 36 is not used, the rate of temperature rise at the end portion Fa in the thickness direction at the outer peripheral portion of the core F is extremely high compared to the rate at which the temperature of the stator coil L rises. The heating could not be continued until the temperature of the stator coil L reached the expected temperature. On the other hand, by using the cylindrical shield 36, the temperature increase rate of the stator coil L increases, while the temperature increase rate of the end portion Fa in the thickness direction in the outer peripheral portion of the core F decreases. The heating could be continued until the temperature of the stator coil L reached the expected temperature.

  In the embodiment described above, the stator M is arranged and heated so that the thickness direction of the core F (the axial direction of the stator M) is up and down. However, the attitude of the stator M is particularly limited. Instead, as shown in FIG. 11, the core F may be heated in the direction in which the thickness direction of the core F (the axial direction of the stator M) is left and right.

  Moreover, although the case where the shielding body 36 has a cylindrical shape is shown, as shown in FIG. 11, a donut-shaped shielding body 36 having a width in the radial direction may be disposed outside the stator coil L. It may be a shield of the shape. In short, any shape that can prevent the magnetic flux generated from the coil head 33 from reaching the outer peripheral portion of the core F may be used.

It is a schematic plan view which shows the manufacturing system of the stator containing the heating apparatus which concerns on one Embodiment of this invention. It is a schematic front view which similarly shows the manufacturing system of a stator. It is a front view which shows the high frequency induction heating apparatus of the stator coil and core which concern on one Embodiment of this invention. It is sectional drawing which similarly shows a high frequency induction heating apparatus. It is a perspective view which similarly shows the coil head in a high frequency induction heating apparatus. It is a perspective view which similarly shows the cylindrical shielding body in a high frequency induction heating apparatus. (A) is explanatory drawing of the transfer condition of the stator by a chuck | zipper apparatus, (B) is a figure which shows the state which transferred and set the stator to the area | region for a heating. (C) is a figure which shows the condition which set the coil head of the high frequency induction heating means to the stator, (D) is explanatory drawing of the condition which transfers the heated stator to the area | region for varnish application | coating. (E) is explanatory drawing of the condition which apply | coats a varnish to the stator coil after a heating. It is front sectional drawing which shows the high frequency induction heating apparatus of the stator coil and core which concern on other embodiment of this invention. It is front sectional drawing which shows the high frequency induction heating apparatus of the stator coil and core which concern on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 High frequency induction heating apparatus 4 Varnish application means 33 Coil head 33a, 33b of high frequency induction heating apparatus Coiled part of coil head 36 Cylindrical shield F Stator coil core Fa Core outer periphery L Stator coil M Stator Ma Stator center Hole

Claims (8)

A high-frequency induction heating means for heating the stator coil and the core is provided by inserting a coil head for high-frequency induction heating into the hollow portion of the annular core around which the stator coil is wound on the inner peripheral side,
The high frequency induction heating coil head has an annular winding portion corresponding to the vicinity of the stator coil on at least one end side of one end side and the other end side excluding an intermediate portion in the thickness direction of the core. And
The high frequency induction heating means further includes:
A shield is provided on the outer side of the core in the thickness direction so as to be coaxial with the core and prevents magnetic flux generated from the coil head from reaching the outer periphery of the core. Stator coil and core heating device.   The stator coil and core heating device according to claim 1, wherein the shield has a cylindrical shape or a donut shape.   The stator coil and core heating device according to claim 1, wherein the shield is disposed in the vicinity of an outer end portion of the stator coil in a radial direction of the core. The stator coil and core heating device according to any one of claims 1 to 3, wherein an outer coil head for high-frequency induction heating is disposed around the outer periphery of the core and positioned at an intermediate portion in the thickness direction of the core. . A stator coil and core heating method in which a high frequency induction heating coil head is inserted into a hollow portion of an annular core in which a stator coil is wound on an inner peripheral side, and the stator coil is heated by high frequency induction,
The high frequency induction heating coil head has an annular winding portion corresponding to the vicinity of the stator coil on at least one end side of one end side and the other end side excluding an intermediate portion in the thickness direction of the core. And
After arranging a shield for preventing the magnetic flux generated from the high frequency induction heating coil head from reaching the outer periphery of the core, coaxially with the core at a position outside the core in the thickness direction, the coil A method for heating a stator coil and a core, wherein an AC voltage is applied to the head to heat the stator coil and the core. The method for heating a stator coil and a core according to claim 5, wherein the shield is cylindrical or donut-shaped. The method for heating a stator coil according to claim 5, wherein the shield is disposed in the vicinity of an outer end portion of the stator coil in a radial direction of the core. The stator coil according to any one of claims 5 to 7, wherein a high frequency induction heating is performed by surrounding an outer peripheral portion of the core and disposing an outer coil head for high frequency induction heating located at an intermediate portion in a thickness direction of the core. Core heating method.

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