Film forming device

Abstract

To provide a film forming device that can reduce the mold release force when removing a resin-coated coil end portion from a mold, and can suppress the occurrence of cracks in a resin coating the coil end portion.SOLUTION: A film forming device according to the present disclosure is a film forming device 1 for coating a coil end portion of a coil with resin R, and includes a mold 10 having an annular first mold portion 11 containing aluminum and having a storage chamber 111 formed therein that concavely surrounds the coil end portion and is filled with resin, and an annular second mold portion 12 containing iron that is formed on the side of the first mold portion 11 opposite to the storage chamber 111, and an IH coil 20 that heats the mold 10 and is arranged to face the surface of the second mold portion 12 opposite to the surface that contacts the first mold portion 11, and the second mold portion 12 is divided into multiple sections by slits 121 extending radially.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a coating forming apparatus. [Background technology]

[0002] For example, there is a case where the coil end portion of a coil wound around a stator, rotor, etc. is coated with resin. Patent Document 1 discloses a coating forming device that uses an induction coil to heat an annular mold while the coil end portion is immersed in thermosetting resin filled inside the mold. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-129605 Summary of the Invention [Problem to be solved by the invention]

[0004] The inventors discovered the following problem with the coating formation device disclosed in Patent Document 1. When releasing the coil end portion from a mold, the coil end portion may be released from a mold that has cooled due to, for example, a facility shutdown. When releasing from the mold at low temperatures, a greater release force is required to release the coil end portion from the mold than when releasing from the mold at high temperatures. A large release force increases residual stress in the resin coating the coil end portion, causing resin cracks. If resin cracks occur, the coil insulation cannot be guaranteed. Therefore, stators and rotors with release forces that exceed the standard may be discarded.

[0005] The present disclosure has been made to solve such problems, and provides a coating forming device that can reduce the demolding force required when releasing a resin-coated coil end portion from a mold, and can suppress the occurrence of cracks in the resin coating the coil end portion. [Means for solving the problem]

[0006] The coating forming device according to the present disclosure is a coating forming device that coats the coil end portion of a coil with resin, and includes a mold including: a first annular mold portion containing aluminum that concavely surrounds the coil end portion and has a storage chamber into which the resin is filled; and a second annular mold portion containing iron that is formed on the side of the first mold portion opposite the storage chamber; and an induction heating coil that heats the mold and is arranged to face the surface of the second mold portion opposite the surface that contacts the first mold portion, wherein the second mold portion is divided into multiple sections by slits extending radially. [Effects of the Invention]

[0007] The present disclosure makes it possible to provide a coating forming device that reduces the mold release force when removing a resin-coated coil end portion from a mold and can suppress the occurrence of cracks in the resin coating the coil end portion. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a side view of a coating forming apparatus according to the present disclosure. [Figure 2] 2A and 2B are cross-sectional views of the coating forming apparatus according to the present disclosure, where Fig. 2A is a cross-sectional view showing the state before cooling, and Fig. 2B is a cross-sectional view showing the state after cooling. [Figure 3] FIG. 3 is a view of the second mold part according to the present disclosure, seen from the opposite side to the surface that contacts the first mold part. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention will be described below through embodiments of the invention, but the invention according to the claims is not limited to the following embodiments. Furthermore, not all of the configurations described in the embodiments are necessarily essential means for solving the problems. For clarity of explanation, the following description and drawings have been omitted and simplified as appropriate. In each drawing, the same elements are given the same reference numerals, and duplicate explanations are omitted as necessary. In the following description, an xyz three-dimensional Cartesian coordinate system is used as appropriate.

[0010] Embodiment 1 <Film forming device> The configuration of a coating formation apparatus according to the present disclosure will be described with reference to the drawings. Fig. 1 is a side view of the coating formation apparatus according to the present disclosure. As shown in Fig. 1, the coating formation apparatus 1 includes a mold 10 and an IH coil 20. The mold 10 includes a first mold part 11 and a second mold part 12. The coating formation apparatus 1 coats the coil end parts with resin by heating the mold 10 using the IH coil 20 while the coil end parts are immersed in resin filled in the mold 10.

[0011] The first mold part 11 is an annular member containing aluminum. FIG. 2 is a cross-sectional view of the coating forming apparatus according to the present disclosure. FIG. 2(a) is a cross-sectional view showing the state before cooling, and FIG. 2(b) is a cross-sectional view showing the state after cooling. As shown in FIG. 2, the first mold part 11 has a receiving chamber 111 formed therein that concavely surrounds the coil end portion and is filled with resin R. More specifically, the receiving chamber 111 is formed as a ring-shaped space that concavely surrounds the coil end portion in a radial cross-sectional view. To coat the coil end portion with resin R, first, the receiving chamber 111 is filled with resin R. Then, the coil end portion is inserted into the receiving chamber 111 in the −z direction and immersed in the resin R, thereby coating the coil end portion with resin R. The coated coil end portion is then released from the receiving chamber 111 in the +z direction. Note that the material of the resin R is not particularly limited as long as it is an insulating and thermosetting material.

[0012] The second mold part 12 is an annular member containing iron. As shown in FIG. 2(a), the second mold part 12 is formed on the surface of the first mold part 11 opposite the storage chamber 111 (the surface on the -z side). More specifically, the second mold part 12 is formed by thermally spraying magnetic iron onto the surface of the first mold part 11 opposite the storage chamber 111. FIG. 3 is a view of the second mold part according to the present disclosure, seen from the opposite side (the -z side) of the surface that contacts the first mold part. As shown in FIG. 3, the second mold part 12 is divided into multiple parts by multiple slits 121 extending in the radial direction.

[0013] Before explaining the effect of the slits 121, we will explain the issues with the mold 10 that includes a second mold portion 12 without the slits 121. When releasing the coil end portions from the mold 10 after they have been coated with the resin R, the coil end portions that remain in the mold 10 due to, for example, a shutdown of the equipment may be released at a low temperature of around 40°C. When releasing the coil end portions from the mold 10 at such low temperatures, a greater release force is required to release the coil end portions from the mold 10 than when the temperature is higher. A large release force increases residual stress in the resin R that has coated the coil end portions, causing the resin R to crack. If cracks occur in the resin R, the insulation of the coil cannot be ensured.

[0014] Next, the reason why the mold release force is large in the mold 10 having the second mold portion 12 in which the slit 121 is not formed will be described. As shown in FIG. 2, the mold 10 is an annular member, and therefore contracts toward the center in the radial direction of the mold 10 when the mold 10 is cooled. Here, the linear expansion coefficient of aluminum, which is the material of the first mold portion 11, (approximately 24×10 -6 / °C), the linear expansion coefficient of iron, which is the material of the second mold portion 12, is about 12×10 -6 / °C), the amount of deformation due to shrinkage of the second mold portion 12 is smaller than the amount of deformation due to shrinkage of the first mold portion 11. Therefore, the deformation of the first mold portion 11 is inhibited by the second mold portion 12. The linear expansion coefficient of the resin R (approximately 20×10 -6 / °C) is close to that of aluminum, which is the material of the first mold portion 11. Therefore, the deformation of the resin R is also hindered by the first mold portion 11, whose deformation is hindered by the second mold portion 12. As a result, the clamping force of the first mold portion 11 against the resin R becomes stronger, and the demolding force required to release the coil end portion from the mold 10 becomes larger.

[0015] On the other hand, the second mold portion 12 according to the present disclosure is divided into multiple pieces by multiple slits 121 extending in the radial direction. As shown in FIGS. 2(b) and 3, each of the divided second mold portions 12 contracts toward the center of the divided second mold portion 12. Therefore, the amount of deformation toward the center in the radial direction of the second mold portion 12 according to the present disclosure is smaller than that of a second mold portion 12 in which no slits 121 are formed. Therefore, the second mold portion 12 according to the present disclosure can suppress the inhibition of deformation of the first mold portion 11, and the mold release force required to release the coil end portion from the mold 10 can be reduced.

[0016] The width of the slits 121 is not particularly limited, but is preferably 5 mm or less. By setting the width of the slits 121 to 5 mm or less, it is possible to suitably suppress temperature unevenness in the mold 10 during heating and cooling. Furthermore, the number of slits 121 is not particularly limited.

[0017] Returning to the explanation of FIG. 1, the IH coil 20 is a coil that heats the mold 10. As shown in FIG. 1, the IH coil 20 is arranged to face the surface (-z side surface) of the second mold part 12 opposite to the surface that contacts the first mold part 11. The IH coil 20 is connected to a power source, for example, via an inverter circuit (not shown). A high-frequency alternating current is applied to the IH coil 20 by controlling the switching of the switching elements of the inverter circuit. This generates magnetic lines of force around the IH coil 20. These magnetic lines of force generate eddy currents in the mold 10. The mold 10 is then heated by Joule heat generated by the eddy currents.

[0018] As described above, with the coating forming device according to the present disclosure, the amount of deformation toward the center in the radial direction of the second mold portion 12 divided into multiple portions by the slits 121 is smaller than that of a second mold portion 12 without the slits 121. Therefore, the second mold portion 12 according to the present disclosure can suppress the inhibition of the deformation of the first mold portion 11. Therefore, when the mold 10 is at a low temperature, the mold release force required to release the coil end portion coated with the resin R from the mold 10 can be reduced, and the occurrence of cracks in the resin R coating the coil end portion can be suppressed.

[0019] The present invention is not limited to the above-described embodiment, and can be modified as appropriate within the scope of the invention. [Explanation of symbols]

[0020] 1 Film forming device 10. Mold 11 First Mold Department 12 Second Mold Department 20 IH coil 111 Containment Room 121 Slit R resin

Claims

[Claim 1] A coating forming device that coats a coil end portion of a coil with resin, a first mold portion having an annular shape and containing aluminum, the first mold portion having a receiving chamber that concavely surrounds the coil end portion and is filled with the resin; a mold including: a second mold portion having an annular shape containing iron, the second mold portion being formed on a surface of the first mold portion opposite the storage chamber; an induction heating coil disposed on the second mold portion so as to face the surface opposite to the surface in contact with the first mold portion, and heating the mold; The second mold part is divided into a plurality of parts by slits extending in the radial direction. Film forming device.

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