JP2012224924A - Method for manufacturing coil with insulating film, and electrodeposition coating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a coil with an insulating film, which can inexpensively manufacture the coil with the insulating film in which a thickness of insulating film portions formed on coil end portions is thick and a thickness of an insulating film portion formed on coil portions to be stored in slots is thin.SOLUTION: The method for manufacturing the coil with the insulating film includes an electrodeposition coating step and a baking step. In the electrodeposition coating step, a precipitation film is electrodeposited to the coil 10 including the slot portions 11 to be inserted into the slots 22 of a stator core 20 and the coil end portions 12 to be exposed from the slots 22. In the baking step, the coil 10 covered with the precipitation film is baked to form an insulating film ZH thereon. In the electrodeposition coating step, especially, the coil 10 is immersed into an electrodeposition solution 41 in an electrodeposition vessel 40 where the electrodeposition solution 41 is caused to flow toward the coil 10, wherein a flow rate of the electrodeposition solution 41 toward the coil end portions 12 is raised relative to that of the electrodeposition solution 41 toward the slot portions 11.

Description

  The present invention relates to a method for manufacturing a coil with an insulating coating for forming an insulating coating on the coil, and more particularly to a method for manufacturing a coil with an insulating coating including an electrodeposition process and a baking process. The present invention also relates to an electrodeposition coating apparatus for electrodepositing a coil.

  For example, in a three-phase AC motor for a hybrid vehicle, a U-phase coil, a V-phase coil, and a W-phase coil are sequentially assembled to the stator core, and the coil end portions exposed from the slots of the stator core overlap each other. There is something. In such overlapping coil end portions, a particularly high voltage (for example, about 1300 V) acts, so that it is necessary to electrically insulate the coil end portions from each other.

  For this reason, in the motor described in Patent Document 1 below, an insulating sheet called interphase insulating paper is assembled between overlapping coil end portions, and a distance between phases for insulating each phase is secured. Yes. The insulating paper is assembled not only between the coil end portions but also between the stator core slot and the coil slot portion inserted into the slot. Therefore, the slots of the stator core and the coil slot are also insulated.

  By the way, the following Patent Document 2 describes a method for manufacturing a coil with an insulating coating in which an insulating coating is formed on the coil itself by electrodeposition in order to ensure the insulation of the coil. In this manufacturing method, first, a coil is immersed in an electrodeposition solution containing a thermosetting resin as a resin component, and a direct current is passed using the electrodeposition solution as an anode and the coil as a cathode. Thereby, particles of the electrodeposition liquid are deposited on the surface of the coil, and a deposited film is formed. Thereafter, the coil on which the deposited film is formed is baked and cooled. In this way, an insulating film that is sufficiently cured and firmly adsorbed is formed on the surface of the coil with a uniform film thickness.

JP 2003-319594 A JP 2010-251615 A

  However, there are the following problems when the insulating properties of the coil are ensured by using interphase insulating paper as in Patent Document 1. In other words, the interphase insulating paper is required to be made of a material having sufficient strength and insulation because large tensile stress and compressive stress are applied and a large voltage is applied. For this reason, the interphase insulating paper itself becomes expensive, and the manufacturing cost of the motor increases in that this interphase insulating paper is used.

  Furthermore, since the interphase insulating paper is designed according to the shape of the coil, the interphase insulating paper has a three-dimensional complicated shape. For this reason, the dedicated assembling machine for assembling the interphase insulating paper performs a complicated operation and is expensive. Thus, the manufacturing cost of the motor also increases in terms of using a dedicated assembly machine. In addition, there is a problem in that the interphase insulating paper, which is a sheet, is torn due to the load generated when the interphase insulating paper is assembled, resulting in an insulation failure.

  Therefore, it is conceivable that the insulation of the coil is secured by using a coil with an insulating coating formed with an insulating coating as described in Patent Document 2 without using interphase insulating paper. In this case, since it is not necessary to use interphase insulating paper and a dedicated assembling machine, the manufacturing cost of the motor can be reduced. Furthermore, since the insulating film is sufficiently cured and firmly adsorbed, it is possible to make it difficult to cause an insulation failure. However, when using this coil with an insulating coating, there are the following problems.

  That is, in the coil with an insulating coating manufactured by the manufacturing method of Patent Document 2, since the insulating coating is formed with a uniform film thickness on the surface of the coil, not only the insulating coating formed on the coil end portion but also the slot. The film thickness is the same also in the insulating film formed in the part. For this reason, in order to sufficiently secure the insulation of the coil end portion, increasing the film thickness of the insulating coating formed on the coil end portion and the slot portion can sufficiently secure the interphase distance between the coil end portions. The ratio (ratio of the cross-sectional area of the conductor of the slot portion to the cross-sectional area of the slot) decreases. As a result, the heat dissipation in the slot deteriorates, and it is necessary to reduce the current supplied to the coil. That is, as the resistance of the coil increases, the temperature of the coil increases, making it impossible to cope with higher motor output.

  On the other hand, in order to increase the slot space factor, if the conductor of the slot portion is made thick and the thickness of the insulating coating formed on the slot is reduced, the thickness of the insulating coating formed on the coil end portion also decreases. . For this reason, in this case, it is impossible to secure a sufficient distance between the coil end portions. In short, in the manufacturing method of Patent Document 2, the film thickness of the insulating coating formed on the coil end portion is increased to ensure a sufficient interphase distance, and the insulating coating formed on the slot portion is reduced to reduce the motor. Can not cope with high output.

  The present invention has been made in order to solve the above-described problems, and has a coil with an insulating coating in which the thickness of the insulating coating formed on the coil end portion is large and the thickness of the insulating coating formed on the slot portion is small. It is providing the manufacturing method of the coil with an insulation film which can be manufactured at low cost, and an electrodeposition coating apparatus.

In order to achieve the above-described problem, a method for manufacturing a coil with an insulating coating of the present invention has the following configuration.
(1) An electrodeposition process for forming a deposited film by electrodeposition on a coil having a slot portion inserted into a slot of a stator core and a coil end portion exposed from the slot; and a coil on which the deposited film is formed On the other hand, in the method of manufacturing a coil with an insulating coating, comprising a baking step of forming an insulating coating by baking, in the electrodeposition step, the coil is immersed in the electrodeposition liquid in an electrodeposition bath. The electrodeposition liquid is caused to flow, and the flow rate of the electrodeposition liquid with respect to the coil end portion is made larger than the flow rate of the electrodeposition liquid with respect to the slot portion.
(2) In the method of manufacturing a coil with an insulating coating described in (1), in the electrodeposition step, the flow of the electrodeposition liquid with respect to the slot portion is upstream of the flow of the electrodeposition liquid from the slot portion. By providing a flow inhibiting means for inhibiting, the flow rate of the electrodeposition liquid with respect to the coil end part is made larger than the flow rate of the electrodeposition liquid with respect to the slot part.
(3) In the method for manufacturing a coil with an insulating coating described in (2), the flow blocking means is disposed upstream of the flow of the electrodeposition liquid from the slot portion so as to surround the slot portion. It has a front wall part and a pair of side wall part extended in the direction where the said electrodeposition liquid flows from the said front wall part outside the said slot part, It is characterized by the above-mentioned.

Moreover, in order to achieve the above-mentioned subject, the electrodeposition coating apparatus of this invention has the following structures.
(4) Suspension for suspending an electrodeposition tank for storing an electrodeposition liquid, a coil having a slot portion inserted into a slot of a stator core and a coil end portion exposed from the slot in a state of being immersed in the electrodeposition liquid In an electrodeposition coating apparatus comprising: an apparatus; a power source for applying a voltage to the coil and the electrodeposition liquid; and a flow device for flowing the electrodeposition liquid toward the coil immersed in the electrodeposition liquid. The flow rate of the electrodeposition liquid with respect to the coil end portion is prevented from flowing to the slot portion by inhibiting the flow of the electrodeposition liquid with respect to the slot portion upstream of the flow of the electrodeposition liquid with respect to the slot portion. The present invention is characterized in that a flow inhibiting means is provided which is larger than the flow rate of the landing liquid.
(5) In the electrodeposition coating apparatus described in (4), the flow blocking means is a front wall portion disposed on the upstream side of the flow of the electrodeposition liquid from the slot portion so as to surround the slot portion. And a pair of side wall portions extending in a direction in which the electrodeposition liquid flows from the front wall portion outside the slot portion.

The effect of the manufacturing method of an above-mentioned coil with an insulation coat is explained.
(1) According to the method for manufacturing a coil with an insulating coating of the present invention, in the electrodeposition step, the flow rate of the electrodeposition liquid with respect to the coil end portion is made larger than the flow rate of the electrodeposition liquid with respect to the slot portion. As a result, the surface of the deposited film formed on the coil end portion is in a dense state with large unevenness, whereas the surface of the deposited film formed on the slot portion is in a rough state with small unevenness. For this reason, by baking the coil on which the deposited film is formed, a large thick insulating film can be formed at the coil end portion, and a small insulating film can be formed at the slot portion. Therefore, according to this coil with an insulating coating, it is possible to sufficiently secure the interphase distance between the coil end portions and increase the slot space factor to cope with the high output of the motor.
In addition, according to this method for manufacturing a coil with an insulating coating, a large thick insulating coating can be formed on the coil end portion in a single electrodeposition step and a subsequent baking step, and a small thickness insulating layer can be formed on the slot portion. A film can be formed. For this reason, it is possible to shorten the electrodeposition processing time in a plurality of electrodeposition steps and subsequent baking steps as compared with the case where a difference in film thickness of the insulating coating is provided between the coil end portion and the slot portion. In addition, a coil with an insulating coating can be manufactured at a low cost based on a decrease in the number of electrodeposition processes.
(2) In this case, a simple structure is provided in which the flow blocking means for blocking the flow of the electrodeposition liquid to the slot portion is provided upstream of the flow of the electrodeposition liquid from the slot portion, and a large thick film is formed An insulating film can be formed, and an insulating film with a small film thickness can be formed in the slot portion. Therefore, since only the flow inhibiting means having a simple configuration is added to the conventionally used electrodeposition coating apparatus, the coil with an insulating coating can be manufactured at low cost.
(3) In this case, in addition to making the flow rate of the electrodeposition liquid substantially zero in the region surrounded by the flow obstruction plate, the difference in potential between the slot portion and the electrodeposition liquid is reduced, The film thickness of the deposited film formed in the slot portion is sufficiently small. For this reason, a large difference in film thickness of the insulating coating can be provided between the coil end portion and the slot portion by the flow blocking plate having a simple configuration.

The effect of the above-described electrodeposition coating apparatus will be described.
(4) According to the electrodeposition coating apparatus of the present invention, the flow-inhibiting means is disposed on the upstream side of the flow of the electrodeposition liquid with respect to the coil immersed in the electrodeposition liquid. Obstructs flow. Thereby, the flow rate of the electrodeposition liquid with respect to a coil end part becomes large compared with the flow rate of the electrodeposition liquid with respect to a slot part. Thus, the surface of the deposited film formed on the coil end portion is in a dense state with large unevenness, whereas the surface of the deposited film formed on the slot portion is in a rough state with small unevenness. For this reason, by subsequently baking the coil on which the deposited film is formed, an insulation film having a large film thickness is formed at the coil end portion, and an insulation film having a small film thickness is formed at the slot portion. Coated coils will be manufactured.
Further, according to this electrodeposition coating apparatus, a flow inhibiting means for inhibiting the flow of the electrodeposition liquid to the slot portion is added to the conventional electrodeposition coating apparatus on the upstream side of the flow of the electrodeposition liquid from the slot portion. It's just a configuration. Therefore, there is almost no cost increase compared with the conventional electrodeposition coating apparatus.
(5) In this case, in addition to making the flow rate of the electrodeposition liquid almost zero in the region surrounded by the flow obstruction plate, the difference in potential between the slot portion and the electrodeposition liquid is reduced, The film thickness of the deposited film formed in the slot portion is sufficiently small. For this reason, a large difference in film thickness of the insulating coating can be provided between the coil end portion and the slot portion by the flow blocking plate having a simple configuration.

It is a perspective view of a coil and a stator core. It is a schematic whole block diagram of an electrodeposition coating apparatus. FIG. 3 is an enlarged view of a coil and a flow inhibition plate shown in FIG. 2. It is the figure which showed the relationship between the flow rate of an electrodeposition liquid, and the film thickness of the insulating film formed in a coil. It is a perspective view of the coil with an insulation film in which the insulation film was formed in the slot part and the coil end part. (A) It is a perspective view of the flow obstruction member in the 1st modification. (B) It is a perspective view of the flow obstruction member in the 2nd modification.

  A method for manufacturing a coil with an insulating coating and an electrodeposition coating apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of the coil 10 and the stator core 20. As shown in FIG. 1, the coil 10 is configured by winding a rectangular conductive wire edgewise and winding it in a spiral shape. The flat conducting wire is made of copper, and one side of the cross section is about 3 mm and the other side of the cross section is about 2 mm. The flat conductive wire may be made of a copper alloy, aluminum, an aluminum alloy, or the like. In the coil 10 shown in FIG. 1, an insulating coating ZH (see FIG. 5) described later is not yet formed.

  As shown in FIG. 1, the stator core 20 is formed by laminating a plurality of hollow disk-shaped metal plates. The stator core 20 is formed with teeth 21 and slots 22 alternately in the circumferential direction. The teeth 21 are formed so as to protrude toward the inside of the stator core 20. The slot 22 is formed by cutting out so that the cross section is substantially U-shaped.

  As shown in FIG. 1, the coil 10 has a slot portion 11, a coil end portion 12, an inner end portion 13, and an outer end portion 14. The coil 10 is assembled to the tooth 21 and the slot 22 in a state where an insulating coating ZH (see FIG. 5) described later is formed. For this reason, the portion inserted into the slot 22 and extending in the vertical direction in FIG. Further, a portion exposed from the slot 22 and indicated by an alternate long and short dash line in FIG.

  Here, for example, when manufacturing a three-phase AC motor for a hybrid vehicle, first, the coil 10 on which 48 insulating coatings ZH (see FIG. 5) are formed is assembled to the stator core 20. Then, the connection wires are connected to the inner end portion 13 and the outer end portion 14 of each coil 10 so that each coil 10 is divided into a U phase, a V phase, and a W phase. In the formed U-phase, V-phase, and W-phase coils 10, the coil end portions 12 overlap. In this embodiment, the case where the shape of the coil 10 is simply shown in FIG. 1 and the coil end portions 12 of the coils 10 of the motor overlap each other will be described.

  Thus, a very high voltage (for example, about 1300 V) acts on the coil end portion 12 when the motor is driven. For this reason, it is necessary to ensure a sufficient inter-phase distance for insulating each phase and to electrically insulate the coil end portions 12 from each other. Although it is necessary to electrically insulate between the slot 22 and the slot portion 11 into which the slot 22 is inserted, it is not necessary to secure a sufficient distance for insulation as in the coil end portion 12. .

  Therefore, in this embodiment, in order to insulate the slot portion 11 and the coil end portion 12 of the coil 10, the insulating coating ZH (see FIG. 5) is formed by electrodeposition and baking. First, the electrodeposition coating apparatus 30 used in the electrodeposition process will be described with reference to FIG. FIG. 2 is a schematic overall configuration diagram of the electrodeposition coating apparatus 30. As shown in FIG. 2, the electrodeposition coating apparatus 30 includes an electrodeposition tank 40, an electrodeposition hanger 50 as a suspension device, a power source 60, a circulation pump 70 as a flow means, and a flow as a flow inhibition means. Inhibiting plate 80 is provided.

  The electrodeposition tank 40 is a container for storing the electrodeposition liquid 41. The electrodeposition liquid 41 forms a deposited film on the surface of the coil 10 by electrodeposition. The coil 10 is immersed in the electrodeposition liquid 41 except for the inner end portion 13 and the outer end portion 14. This electrodeposition liquid 41 is a polyamideimide-based electrodeposition liquid comprising a polyamideimide resin having high insulation and heat resistance. The electrodeposition liquid 41 is not limited to the polyamide-imide electrodeposition liquid, and can be appropriately changed. For example, a polyimide electrodeposition liquid containing a polyimide resin or an epoxy resin containing an epoxy resin can be used. A system electrodeposition solution may also be used. For the polyamideimide-based electrodeposition liquid, for example, a cationic electrodeposition coating composition described in JP-A-2009-2556489 can be used.

  The electrodeposition hanger 50 is for suspending the immersed coil 10. Specifically, in the electrodeposition hanger 50, the inner end portion 13 and the outer end portion 14 are electrically connected to each other in order to prevent a deposited film from being formed on the inner end portion 13 and the outer end portion 14 of the coil 10 by electrodeposition. The coil 10 is suspended so as to be exposed from the landing liquid 41. The electrodeposition hanger 50 is made of conductive steel and is connected to the cathode side of the power source 60. Here, in FIG. 2, the electrodeposition hanger 50 suspends one coil 10, but the electrodeposition hanger 50 may suspend, for example, 48 coils 10. The coil 10 may be immersed by masking the electrodeposition liquid 41 so as not to contact the inner end portion 13 and the outer end portion 14.

  The power source 60 is for applying a voltage with the electrodeposition liquid 41 on the anode side and the coil 10 on the cathode side. The anode side of the power source 60 is connected to the electrode rod 61. The electrode rod 61 is assembled to the rear wall 43 of the electrodeposition tank 40, and the lower end portion is immersed in the electrodeposition liquid 41. Thus, an electric circuit of power source 60-electrode bar 61-electrodeposition liquid 41-coil 10-electrodeposition hanger 50-power source 60 is formed. For this reason, when a direct current flows from the power source 60, cationic electrodeposition is performed with the electrodeposition liquid 41 on the anode side and the coil 10 on the cathode side.

  The circulation pump 70 is for flowing the electrodeposition liquid 41. The circulation pump 70 feeds the electrodeposition liquid 41 into the electrodeposition tank 40 through a delivery pipe 71 connected to the front wall 42 of the electrodeposition tank 40. Further, the electrodeposition liquid 41 in the electrodeposition tank 40 flows toward the circulation pump 70 through the discharge pipe 72 connected to the rear wall 43 of the electrodeposition tank 40. Thus, the circulation pump 70 causes the electrodeposition liquid 41 in the electrodeposition tank 40 to flow in the direction indicated by the arrow in FIG. 2 so that the flow rate is about 15 cm / s. The direction of the coil 10 is set so that the direction indicated by the arrow in FIG. 2 through which the electrodeposition liquid 41 flows and the direction penetrating the inside of the coil 10 in which the flat wire is spirally wound are substantially orthogonal to each other. Has been.

  By the way, as shown in FIG. 2, the electrodeposition coating apparatus 30 of this embodiment is provided with a flow inhibition plate 80 as a flow inhibition means. The flow blocking plate 80 is for inhibiting the flow of the electrodeposition liquid 41 with respect to the slot portion 11 on the upstream side of the flow of the electrodeposition liquid 41 from the slot portion 11 of the coil 10. The flow blocking plate 80 is supported by a support device (not shown) so as to be disposed in the electrodeposition liquid 41 of the electrodeposition tank 40. The flow blocking plate 80 may be supported by the electrodeposition hanger 50. The flow blocking plate 80 is made of a metal such as copper. Here, FIG. 3 is an enlarged view of the coil 10 and the flow blocking plate 80 shown in FIG.

  As shown in FIG. 3, the flow blocking plate 80 includes a front wall portion 81 disposed on the upstream side of the flow of the electrodeposition liquid 41 from the slot portion 11 so as to surround the slot portion 11, and an outer side from the slot portion 11. And a pair of side wall portions 82 extending in the direction in which the electrodeposition liquid 41 flows from the front wall portion 81. The front wall portion 81 is a rectangular thin plate, and when viewed in the direction in which the electrodeposition liquid 41 flows on the upstream side of the flow of the electrodeposition liquid 41, the coil end portion 12 can be seen, whereas the slot portion 11 is formed. It is arranged so that it cannot be seen. Each side wall portion 82 is a rectangular thin plate and extends from the coil 10 in the direction in which the electrodeposition liquid 41 flows. In the flow blocking plate 80, the height dimension H is about 70 mm, the width dimension W is about 50 mm, and the depth dimension D is about 80 mm. Moreover, in the wound part of the coil 10, the height dimension is about 80 mm, the width dimension is about 30 mm, and the depth dimension is about 70 mm. In addition, the dimension of the flow obstruction board 80 and the dimension of the coil 10 can be changed suitably.

  Thus, in the electrodeposition liquid 41 flowing toward the coil 10, the flow with respect to the coil end portion 12 is not obstructed by the flow inhibition plate 80, so the flow rate of the electrodeposition liquid 41 with respect to the coil end portion 12 is 15 cm / s. Maintained to a certain extent. On the other hand, since the flow with respect to the slot portion 11 is inhibited by the flow inhibition plate 80, the flow rate of the electrodeposition liquid 41 with respect to the slot portion 11 becomes approximately 0 cm / s. That is, in the region surrounded by the flow blocking plate 80, the electrodeposition liquid 41 stays and stagnates, so the flow rate of the electrodeposition liquid 41 with respect to the slot portion 11 is approximately 0 cm / s. In addition, the effect produced when the flow rate of the electrodeposition liquid 41 with respect to the coil end part 12 is larger than the flow rate of the electrodeposition liquid 41 with respect to the slot part 11 will be described in detail later.

  Next, the electrodeposition process will be described. In a state where the electrodeposition liquid 41 is flowing toward the coil 10, the power source 60 applies a voltage with the electrodeposition liquid 41 as an anode and the coil 10 as a cathode to flow a direct current. As a result, the positively charged particles in the electrodeposition liquid 41 are electrophoresed toward the coil 10 and are deposited on the slot portion 11 and the coil end portion 12. Thus, a deposited film is formed on the slot portion 11 and the coil end portion 12. The deposited film is adsorbed in a state of being dripped into the slot portion 11 and the coil end portion 12.

  Next, the baking process will be described. First, the coil 10 on which the deposited film is formed is placed in a baking and drying furnace. Next, the deposited film formed on the slot portion 11 and the coil end portion 12 is uniformly heated using, for example, infrared rays or hot air. Thereafter, the coil 10 is cooled. In this way, the deposited coating is sufficiently cured and firmly adsorbed to the slot portion 11 and the coil end portion 12, whereby the insulating coating ZH (see FIG. 5) is formed on the slot portion 11 and the coil end portion 12. Hereinafter, the coil 10 on which the insulating coating ZH is formed is referred to as an insulating coating-coated coil 10A.

  Here, the effect produced when the flow rate of the electrodeposition liquid 41 with respect to the coil end part 12 is larger than the flow rate of the electrodeposition liquid 41 with respect to the slot part 11 is demonstrated using FIG. FIG. 4 is a diagram showing the relationship between the flow rate of the electrodeposition liquid and the film thickness of the insulating coating formed on the coil. In FIG. 4, when the flow rate of the experimental electrodeposition liquid is changed using the same experimental electrodeposition liquid as the electrodeposition liquid 41 and the same experimental coil as the coil 10, it is formed on the surface of the experimental coil. The experimental results of measuring the thickness of the insulating coating are shown by black circles. Hereinafter, the experimental electrodeposition liquid is referred to as an electrodeposition liquid 41X, and the experimental coil is referred to as a coil 10X. Here, a black circle is an experimental result when the flow rate of the electrodeposition liquid 41X is changed by the circulation pump 70 without using the flow inhibition plate 80 described above.

As shown in FIG. 4, it can be seen that the greater the flow rate of the electrodeposition liquid 41X, the greater the thickness of the insulating coating. This is based on the following reason. When a deposited film is formed on the surface of the coil 10X by electrodeposition, minute bubbles of H ₂ are generated. The timing at which the bubbles are separated from the surface of the deposited coating varies depending on the flow rate of the electrodeposition liquid 41X. That is, when the flow rate of the electrodeposition liquid 41X is small, the H ₂ bubbles grow greatly and then move away from the surface of the deposited film, and the surface of the deposited film becomes rough with small irregularities. Thereby, when this depositing film is baked and leveled (film thickness adjustment), the film thickness of an insulating film becomes small. On the other hand, when the flow rate of the electrodeposition liquid 41X is large, the H ₂ bubbles are separated from the surface of the deposited coating in a small state, and the surface of the deposited coating is in a dense state with large irregularities. Thereby, when this depositing film is baked and leveled, the film thickness of an insulating film becomes large. Thus, when the flow rate of the electrodeposition liquid 41X is 15 cm / s, the film thickness of the insulating coating is about 120 μm, whereas when the flow rate of the electrodeposition liquid 41X is 0 cm / s, the insulating film is insulated. The film thickness is about 85 μm.

  By the way, in FIG. 4, when the flow inhibition plate 80 is used as in the present embodiment, the coil 10X is surrounded by the flow inhibition plate 80 (the portion corresponding to the slot portion 11). The film thickness of the insulating coating is indicated by a double circle. In the double circle, the thickness of the insulating coating is about 75 μm. Thus, when the flow inhibition plate 80 is used, the film thickness of the insulating coating is further reduced compared to the case where the flow rate of the electrodeposition liquid 41X is set to 0 cm / s without using the flow inhibition plate 80. This is based on the following reason.

  The difference in potential between the portion of the coil 10X surrounded by the flow inhibition plate 80 and the electrodeposition liquid 41X is compared to the difference in potential between the portion of the coil 10X and the electrodeposition liquid 41X when the flow inhibition plate 80 is not used. And become smaller. Thus, when the flow inhibition plate 80 is used, the positively charged particles in the electrodeposition liquid 41X are less likely to be attracted to the surface of the coil 10X than when the flow inhibition plate 80 is not used. The film thickness of the coating is reduced. Thus, in the case where the flow inhibition plate 80 is used, in addition to the flow velocity of the electrodeposition liquid 41X being approximately 0 cm / s in the region surrounded by the flow inhibition plate 80, the coil 10X and the electrodeposition liquid 41X By reducing the difference in potential, the thickness of the insulating coating is further reduced.

  Here, FIG. 5 is a perspective view of the coil 10A with an insulating coating manufactured in the electrodeposition process and the baking process of the present embodiment. As shown in FIG. 5, the insulating coating ZH that is sufficiently cured and firmly adsorbed is formed in the slot portion 11 and the coil end portion 12. For this reason, the insulating coating-coated coil 10A is less likely to cause insulation failure due to cracks or the like when it is assembled to the teeth 21 and the slots 22 of the stator 20.

  As shown in FIG. 5, the insulating coating ZH formed on the slot portion 11 is referred to as a slot coating ZH1, and the insulating coating ZH formed on the coil end portion 12 is referred to as a coil end coating ZH2. The film thickness of the slot coating ZH1 is about 75 μm. For this reason, the slot space factor (ratio of the cross-sectional area of the flat wire of the slot portion 11 to the cross-sectional area of the slot 22) can be increased. That is, by making the flat rectangular wire of the slot portion 11 thick, the resistance of the coil 10 can be reduced and the temperature of the coil 10 can be lowered. Therefore, the current supplied to the coil 10 can be increased, and the motor can be increased in output. On the other hand, the film thickness of the coil end coating ZH2 is about 120 μm. For this reason, the interphase distance of the coil end part 12 can be secured sufficiently, and the insulation of the coil end part 12 can be secured sufficiently.

  In addition, the coil 10A with an insulation coating can sufficiently secure the insulation of the coil end portion 12 without using conventional interphase insulating paper in a state where it is assembled to the stator 20. Therefore, it is not necessary to use expensive interphase insulating paper and a dedicated assembling machine for assembling the interphase insulating paper, and the manufacturing cost of the motor can be reduced.

The effect of this embodiment is demonstrated.
First, the effect of the manufacturing method of a coil with an insulating coating will be described. In the electrodeposition process, the flow rate of the electrodeposition liquid 41 with respect to the coil end portion 12 is made larger than the flow rate of the electrodeposition liquid 41 with respect to the slot portion 11. As a result, the surface of the deposited film formed on the coil end portion 12 is in a dense state with large unevenness, whereas the surface of the deposited film formed on the slot portion 11 is in a rough state with small unevenness. . For this reason, by baking the coil 10 on which the deposited film is formed, a coil end film ZH2 having a large thickness can be formed as shown in FIG. 5, and a slot film ZH1 having a small film thickness can be formed. Can do. Therefore, according to this coil with insulation coating 10A, the interphase distance of the coil end portion 12 can be sufficiently secured, and the slot space factor can be increased to cope with the high output of the motor.

  In addition, according to this method of manufacturing a coil with an insulating coating, a large thick coil end coating ZH2 can be formed and a small thickness slot coating ZH1 can be formed by a single electrodeposition step and a subsequent baking step. be able to. For this reason, when a difference in film thickness of the insulating coating is provided between the coil end portion 12 and the slot portion 11 in a plurality of electrodeposition steps and subsequent baking steps, for example, the slot portion 11 is charged once. Compared with the case where electrodeposition is performed twice or more times on the coil end portion 12, the electrodeposition processing time can be shortened, and the coil with an insulating coating can be manufactured at a lower cost based on a decrease in the number of electrodeposition processes. 10A can be manufactured.

  In addition, according to the method for manufacturing the coil with an insulating coating, the flow blocking means (flow blocking plate 80) inhibits the flow of the electrodeposition liquid 41 with respect to the slot portion 11 upstream of the flow of the electrodeposition liquid 41 from the slot portion 11. The coil end coating ZH2 having a large thickness can be formed and the slot coating ZH1 having a small thickness can be formed. Therefore, the flow coating means having a simple configuration is simply added to the conventionally used electrodeposition coating apparatus, and thus the coil with insulating coating 10A can be manufactured at low cost.

  Further, according to this method for manufacturing a coil with an insulating coating, in addition to setting the flow rate of the electrodeposition liquid 41 to approximately 0 cm / s in the region surrounded by the flow blocking plate 80, the slot portion 11 and the electrodeposition liquid When the potential difference from 41 is reduced, the thickness of the deposited film formed in the slot portion 11 is sufficiently reduced. For this reason, a large difference in film thickness of the insulating coating ZH can be provided between the coil end portion 12 and the slot portion 11 by the flow blocking plate 80 having a simple configuration.

  In addition, according to this method for manufacturing a coil with an insulating coating, various types of coils can be handled by changing the position where the flow inhibition plate 80 is disposed and the shape of the flow inhibition plate 80. That is, even by changing the shape and position of the flow blocking plate 80, a difference in the thickness of the insulating coating can be easily provided between the coil end portion and the slot portion even if the coils have different shapes. . Therefore, it is possible to sufficiently cope with a case where a large number of types of coils are produced in a small amount only by adding the flow blocking plate 80 to the conventional electrodeposition coating apparatus.

  Next, the effect of the electrodeposition coating apparatus 30 will be described. The flow blocking means (flow blocking plate 80) is a flow of the electrodeposition liquid 41 with respect to the slot portion 11 on the upstream side of the flow of the electrodeposition liquid 41 with respect to the coil 10 immersed in the electrodeposition liquid 41. Inhibits. Thereby, the flow rate of the electrodeposition liquid 41 with respect to the coil end part 12 becomes larger than the flow rate of the electrodeposition liquid 41 with respect to the slot part 11. In this way, the surface of the deposited film formed on the coil end portion 12 is in a dense state with large unevenness, whereas the surface of the deposited film formed on the slot portion 11 is in a rough state with small unevenness. Therefore, by subsequently baking the coil 10 on which the deposited film is formed, a coil end film ZH2 having a large thickness is formed as shown in FIG. 5, and a slot film ZH1 having a small film thickness is formed. The formed insulating coating-coated coil 10A is manufactured.

  Moreover, according to this electrodeposition coating apparatus 30, the flow of the electrodeposition liquid 41 with respect to the slot part 11 is inhibited in the upstream of the flow of the electrodeposition liquid 41 from the slot part 11 with respect to the conventional electrodeposition coating apparatus. The flow blocking means (flow blocking plate 80) is simply added. Therefore, there is almost no cost increase compared with the conventional electrodeposition coating apparatus.

  Further, according to the electrodeposition coating apparatus 30, in addition to setting the flow rate of the electrodeposition liquid 41 to approximately 0 cm / s in the region surrounded by the flow blocking plate 80, the slot portion 11 and the electrodeposition liquid 41 By reducing the potential difference between the two, the film thickness of the deposited film formed in the slot portion 11 becomes sufficiently small. For this reason, a large difference in film thickness of the insulating coating ZH can be provided between the coil end portion 12 and the slot portion 11 by the flow blocking plate 80 having a simple configuration.

As mentioned above, in the manufacturing method of the coil with an insulation film and electrodeposition coating apparatus which concern on this invention, this invention is not limited to this, A various change is possible in the range which does not deviate from the meaning.
In the present embodiment, as shown in FIG. 3, as the flow inhibition means, a flow inhibition plate 80 having a front wall portion 81 and a pair of side wall portions 82 is used. It can be changed as appropriate.
For example, as in the first modified embodiment shown in FIG. 6A, the flow inhibition means is a cylindrical flow inhibition member having a front wall portion 81, a pair of side wall portions 82, and a rear wall portion 83. 80A may be sufficient. In this case, it is possible to prevent the electrodeposition liquid 41 from entering the slot portion 11 from the pair of side wall portions 82.
Further, as in the second modified embodiment shown in FIG. 6B, the flow inhibition means may be a flow inhibition member 80 </ b> B having only the front wall portion 81. In this case, the configuration of the flow inhibition means is simplified as compared with the case where the flow inhibition plate 80 is used. In addition, the shape of the front wall portion 81 can be changed as appropriate, and the cross section may be a V-shape projecting upstream of the flow of the electrodeposition liquid 41.

In the present embodiment, the flow inhibition means is a flow inhibition plate 80 supported by a support device (not shown) or the electrodeposition hanger 50, but the flow integrally formed on the bottom wall of the electrodeposition tank 40 or the like. It may be an inhibiting part.
Further, in place of the flow preventing means (flow blocking plate 80) that obstructs the flow of the electrodeposition liquid 41 with respect to the slot portion 11, a nozzle is arranged on the upstream side of the flow of the electrodeposition liquid 41 from the coil end portion 12, and the coil The flow rate of the electrodeposition liquid 41 with respect to the end part 12 may be made larger than the flow rate of the electrodeposition liquid 41 with respect to the slot part 11.

  Further, in the present embodiment, the power supply 60 applied the voltage with the electrodeposition liquid 41 as the anode and the coil 10 as the cathode to perform the cationic electrodeposition, but the power supply has the coil as the anode and the electrodeposition liquid as the cathode. As described above, anion electrodeposition may be performed by applying a voltage.

DESCRIPTION OF SYMBOLS 10 Coil 11 Slot part 12 Coil end part 20 Stator 21 Teeth 22 Slot 30 Electrodeposition coating apparatus 40 Electrodeposition tank 41 Electrodeposition liquid 50 Electrodeposition hanger 60 Power supply 70 Circulation pump 80 Flow inhibition plate 81 Front wall part 82 Side wall part ZH Insulation Coating ZH1 Slot coating ZH2 Coil end coating

Claims (5)

An electrodeposition step of forming a deposited film by electrodeposition on a coil having a slot portion inserted into a slot of a stator core and a coil end portion exposed from the slot;
In the method of manufacturing a coil with an insulating coating, comprising a baking step of forming an insulating coating by baking the coil on which the deposited coating is formed,
In the electrodeposition step, the electrodeposition liquid is caused to flow toward the coil immersed in the electrodeposition liquid in an electrodeposition tank, and the flow rate of the electrodeposition liquid with respect to the coil end portion is set to be the electric current with respect to the slot portion. A method for manufacturing a coil with an insulating coating, wherein the coil is made larger than a flow rate of the liquid. In the manufacturing method of the coil with an insulation film described in Claim 1,
In the electrodeposition step, the electrodeposition liquid for the coil end portion is provided by providing a flow inhibition means for inhibiting the flow of the electrodeposition liquid to the slot portion upstream of the slot portion from the flow of the electrodeposition liquid. The method of manufacturing a coil with an insulating coating is characterized in that the flow rate of the coil is larger than the flow rate of the electrodeposition liquid with respect to the slot portion. In the manufacturing method of the coil with an insulation film described in Claim 2,
The flow blocking means includes a front wall portion disposed on the upstream side of the flow of the electrodeposition liquid from the slot portion so as to surround the slot portion, and the electrodeposition from the front wall portion outside the slot portion. And a pair of side wall portions extending in a direction in which the liquid flows. An electrodeposition tank for storing an electrodeposition liquid;
A suspension device for suspending a coil having a slot portion inserted into a slot of a stator core and a coil end portion exposed from the slot in a state of being immersed in the electrodeposition liquid;
A power source for applying a voltage to the coil and the electrodeposition liquid;
In the electrodeposition coating apparatus comprising: a fluidizing device that causes the electrodeposition fluid to flow toward the coil immersed in the electrodeposition fluid;
By inhibiting the flow of the electrodeposition liquid with respect to the slot part upstream of the flow of the electrodeposition liquid from the slot part, the flow rate of the electrodeposition liquid with respect to the coil end part is changed to the electrodeposition with respect to the slot part. An electrodeposition coating apparatus provided with a flow inhibiting means for increasing the flow rate of the liquid. In the electrodeposition coating apparatus according to claim 4,
The flow blocking means includes a front wall portion disposed on the upstream side of the flow of the electrodeposition liquid from the slot portion so as to surround the slot portion, and the electrodeposition from the front wall portion outside the slot portion. An electrodeposition coating apparatus comprising a pair of side wall portions extending in a direction in which the liquid flows.

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