Two-member bonding method and motor manufacturing method

Abstract

In the present invention, after a sheet (14) that has been heated in a first heating step and has exhibited adhesiveness is affixed to a magnet (13), which is a first member: the magnet (13) is inserted into a slot hole (12), which is an insertion hole of a rotor core (10), which is a second member; and the magnet (13) is bonded to an inner surface of the slot hole (12), e.g. an inner surface (121) on an outer side in the radial direction, via expansion and curing of the sheet (14) due to the sheet (14) being heated to a second temperature (T2) together with the rotor core (10) in a second heating step. As a result, the person-hours required for the bonding of the magnet (13) can be reduced in a manufacturing process for a motor (M).

Description

Method for bonding two components and method for manufacturing a motor

[0001] The present invention relates to a method for bonding two members and a method for manufacturing a motor.

[0002] A conventional method for bonding two members and a conventional method for manufacturing a motor are disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-222999.

[0003] In summary, in this method of bonding two components and manufacturing a motor, one side of a resin sheet, which is an adhesive sheet, is attached to the side of a magnet, which is one of the components. The release liner on the other side of the resin sheet is then peeled off, and the other side of the resin sheet is attached to each slot hole of the rotor core of the motor, thereby fixing the magnet to each slot hole of the rotor core, which is the other component, via the resin sheet.

[0004] Japanese Patent Application Laid-Open No. 2020-011768

[0005] However, with the conventional method of bonding two components and the conventional method of manufacturing a motor, when bonding the magnets to the slot holes, it is necessary to peel off the release liner from the resin sheet attached to the magnets, which increases manufacturing costs by the amount of work required to peel off the release liner, and there is still room for improvement.

[0006] Therefore, the present invention was devised in consideration of the technical problems with the conventional methods for bonding two components and methods for manufacturing motors, and aims to provide a method for bonding two components and a method for manufacturing motors that can reduce the number of steps involved in bonding.

[0007] In one aspect of the present invention, a sheet that exhibits adhesiveness and expandability when heated is heated to a first temperature at which the sheet exhibits the adhesiveness, the sheet heated to the first temperature is attached to a first member, the first member to which the sheet is attached is inserted into an insertion hole provided in a second member, and the first member inserted into the insertion hole is heated to a second temperature that is higher than the first temperature and at which the sheet expands and hardens to adhere to the inner surface of the insertion hole.

[0008] According to the present invention, the number of steps involved in bonding can be reduced.

[0009] 1 is a schematic diagram showing the configuration of a motor according to a first embodiment of the present invention; 2 is a schematic diagram showing a first heating step and a sheet attaching step; 3 is a flowchart of the first heating step and the sheet attaching step shown in FIG. 4; 4 is a perspective view showing the manufacturing process of the motor shown in FIG. 1, where (a) is a schematic diagram showing the member (magnet) insertion step, (b) is a schematic diagram showing the second heating step, and (c) is a schematic diagram showing the magnetizing step; 5 is a cross-sectional view showing the manufacturing process of the motor shown in FIG. 1, where (a) is a schematic diagram showing the member (magnet) insertion step, (b) is a schematic diagram showing the second heating step, and (c) is a schematic diagram showing the magnetizing step; 6 is a flowchart of the member (magnet) insertion step, the second heating step, and the magnetizing step shown in FIG. 7; 8 is a schematic diagram showing the insertion mode of a magnet into a rotor core, where (a) is a first mode, (b) is a second mode, and (c) is a third mode; 9 is a diagram showing the bonding mode of a magnet to a rotor core, where (a) is a first mode, (b) is a second mode, (c) is a third mode, and (d) is a fourth mode; 10 is a schematic diagram showing the configuration of a motor according to a second embodiment of the present invention. 10A to 10C are cross-sectional views showing the manufacturing process of the motor shown in FIG. 9, in which (a) is a sheet attaching step, (b) is a member (magnet) inserting step, and (c) is a schematic view showing a second heating step.

[0010] Hereinafter, embodiments of the method for bonding two members and the method for manufacturing a motor according to the present invention will be described in detail with reference to the drawings. Note that in each of the following embodiments, the method for bonding two members will be described as being applied to a motor manufacturing method, as in the conventional method.

[0011] First Embodiment FIGS. 1 to 8 show a first embodiment of a method for bonding two members and a method for manufacturing a motor according to the present invention.

[0012] 1 is a schematic diagram of a motor M according to this embodiment, showing the general configuration of the motor M. In addition, the direction along the rotation axis Z in FIG. 1 will be referred to as the "axial direction," the direction perpendicular to the rotation axis Z as the "radial direction," and the direction around the rotation axis Z as the "circumferential direction."

[0013] For example, as shown in FIG. 1 , the motor M according to this embodiment is a so-called inner rotor type, and includes a stator (not shown), a cylindrical rotor 1 that is rotatably arranged on the inner periphery of the stator, and a rotating shaft 2 that is fixed to the inner periphery of the rotor 1 and rotates integrally with the rotor 1.

[0014] The rotor 1 has a rotor core 10, which is a rotor iron core. The rotor core 10 is made of, for example, laminated steel plates formed by stacking multiple electromagnetic steel plates, and corresponds to the second member of the present invention. The rotor core 10 has a shaft insertion hole 11 that penetrates in the axial direction in the center, and a plurality of slot holes 12 that extend in the axial direction and correspond to the insertion holes of the present invention are provided inside and arranged in parallel in the circumferential direction.

[0015] The rotating shaft 2 is fixed in the shaft insertion hole 11 by, for example, press-fitting. A roughly rectangular plate-shaped magnet 13, which corresponds to the first member of the present invention, is inserted axially into each slot hole 12. Each slot hole 12 has a circumferential dimension 12X and a radial dimension 12Y that are slightly larger than the width dimension 13X and thickness dimension 13Y of the magnet 13 when the sheet 14 is attached. In other words, before the magnet 13 is inserted into each slot hole 12, i.e., before the sheet 14, which will be described later, is heated, a predetermined gap C is formed between the inner surfaces 121, 122, 123, and 124 of each slot hole 12 and the outer surfaces 131, 132, 133, and 134 of the magnet 13 that face the inner surfaces 121, 122, 123, and 124.

[0016] The magnet 13 is adhered to the inner surfaces 121, 122, 123, and 124 of each slot hole 12 via a sheet 14 attached to at least one outer surface 131, 132, 133, and 134 facing the inner surfaces 121, 122, 123, and 124 of each slot hole 12. In other words, the sheet 14 only needs to be interposed between one or more outer surfaces 131, 132, 133, and 134 of the magnet 13 facing each slot hole 12 and the inner surfaces 121, 122, 123, and 124 of each slot hole 12. In this case, the position on the magnet 13 where the sheet 14 is attached (to which outer surface 131, 132, 133, and 134) and the number of outer surfaces 131, 132, 133, and 134 to which the sheet 14 is attached can be changed as desired depending on the specifications of the motor M, etc.

[0017] The base material of sheet 14 is a thermosetting resin, and contains an expandable component with foaming properties, such as isopentane. That is, when heated, sheet 14 softens the thermosetting resin and expands the expandable component with foaming properties, thereby filling gaps C between outer surfaces 131, 132, 133, and 134 of magnet 13 and inner surfaces 121, 122, 123, and 124 of each slot hole 12, and thereby adhering closely to inner surfaces 121, 122, 123, and 124 of each slot hole 12.

[0018] (Motor Manufacturing Process) Fig. 2 is a schematic diagram of the first heating step and the sheet attaching step, and Fig. 3 is a flowchart of the first heating step and the sheet attaching step shown in Fig. 2 .

[0019] In the first heating step and the sheet attaching step, the sheet 14 is heated and attached to the magnet 13 by a sheet heating and attaching device 3 as shown in Fig. 2, for example. The sheet heating and attaching device 3 has a sheet roll storage section 31, a heat-generating roller 32 as a sheet heating section, a roller conveyor 33 as a sheet transport section, a magnet supply section 34, and a sheet cutter 35 as a sheet cutting section.

[0020] The sheet roll storage section 31 stores a sheet roll 140 in which a long, strip-shaped sheet 14 is wound into a roll. The sheet roll storage section 31 also has a sheet drawer section 310 that is open to allow communication between the inside and outside of the sheet roll storage section 31 and exposes the end portion (sheet 14) of the sheet roll 140 to the outside. The sheet drawer section 310 is formed with an opening that is, for example, roughly rectangular (not shown) and is larger than the width dimension of the sheet 14 and is sufficiently larger than the thickness dimension of the sheet 14.

[0021] The heat-generating rollers 32 are a pair of upper and lower rollers provided in the sheet drawer 310, and the upper roller 321 and the lower roller 322 generate heat, for example, by passing electricity through them. That is, the upper roller 321 and the lower roller 322 generate heat, which heats the sheet 14 sandwiched between the rollers 321 and 322. Furthermore, the upper roller 321 and the lower roller 322 rotate, causing the strip-shaped sheet 14 to be drawn out from the sheet roll 140.

[0022] The roller conveyor 33 is disposed horizontally adjacent to the lower roller 322 of the heat-generating roller 32, and as the roller conveyor 33 rotates, it horizontally conveys the sheet 14 that has been heated by the heat-generating roller 32 and drawn out. The roller conveyor 33 is also disposed below the magnet supply unit 34 so as to face the bottom surface of the magnet 13 discharged from the magnet supply unit 34.

[0023] The magnet supply unit 34 is formed in a generally cylindrical shape and is capable of accommodating a plurality of magnets 13 stacked in the thickness direction. The magnet supply unit 34 supplies the magnets 13 to the sheet 14 by discharging the magnets 13 one by one from an opening provided at the bottom end toward the sheet 14 moving on the roller conveyor 33.

[0024] The sheet cutter 35 is disposed adjacent to the magnet supply unit 34 immediately before the magnet supply unit 34 in the feed direction of the sheet 14. The sheet cutter 35 has a pair of upper and lower cutters 351, 352, and cuts the strip-shaped sheet 14 by sandwiching it between the cutters 351, 352. At this time, the end face of the sheet 14 cut by the sheet cutter 35 is arranged to roughly coincide with the rear end 13b of the magnet 13 in the feed direction of the sheet 14.

[0025] FIG. 3 shows a flowchart of the first heating step and the sheet attaching step shown in FIG.

[0026] The first heating step and the sheet bonding step performed using the sheet heating bonding device 3 will be described in detail below based on the flowchart shown in FIG. 3 and with reference to the process diagram shown in FIG.

[0027] First, as shown in step S1 of Fig. 3, the magnets 13 and the sheet 14 (sheet roll 140) are set in their initial positions. Specifically, as shown in Fig. 2(a), for example, the magnets 13 are set in the magnet supply unit 34 so that they are stacked in the thickness direction. In addition, the front end 14a, which corresponds to the terminal end of the sheet roll 140, is sandwiched between the heat-generating roller 32 (between the upper roller 321 and the lower roller 322). Thereafter, the heat-generating roller 32 is heated by energizing it.

[0028] Thereafter, as shown in step S2 of FIG. 3 , the sheet 14 is fed by the heat roller 32. Specifically, as shown in FIG. 2B , the sheet 14 is fed by rotating the heat roller 32, which has been heated by energization (sheet heating process). The sheet 14 fed by the heat roller 32 is then conveyed by the roller conveyor 33 in a direction away from the sheet roll storage section 31. Here, in the sheet heating process, the sheet 14 is heated to a first temperature T1 according to the present invention, at which the sheet 14 becomes adhesive. Specifically, the heat roller 32 heats the sheet 14 to 50 to 90°C. This causes the sheet 14 to become adhesive. Note that the adhesiveness exerted in the sheet heating process only needs to be sufficient to prevent the sheet 14 from peeling off the magnets 13 when the magnets 13 are inserted into the slot holes 12 of the rotor core 10 in the component (magnet) insertion process described below.

[0029] Next, as shown in step S3 of Fig. 3, magnets 13 are placed on the sheet 14. Specifically, as shown in Fig. 2(c), for example, when the leading edge 14a of the sheet 14 roughly coincides with the leading edge 13a of the magnet 13 in the feed direction of the sheet 14, magnets 13 are discharged one by one from the magnet supply unit 34 and placed on the sheet 14 supported by the roller conveyor 33. The magnets 13 placed on the sheet 14 are then pressed against the upper surface of the sheet 14 by their own weight, and are adhered to the upper surface of the sheet 14 by the adhesive force of the heated sheet 14 (sheet adhering process). In other words, the sheet 14 is adhered to the outer surface 131, which is one end surface (lower end surface) of the magnet 13 in the thickness direction.

[0030] Next, as shown in step S4 of FIG. 3 , the sheet 14 on which the magnets 13 were placed in step S3 is cut. Specifically, when the magnets 13 are placed on the sheet 14, the trailing edge 14b of the sheet 14 is cut by the sheet cutter 35, as shown in FIG. 2( d ), for example (sheet cutting process). After the sheet 14 is cut, as shown in step S5 of FIG. 3 , the sheet 14 is fed out by the heat roller 32. Specifically, as shown in FIG. 2( e ), for example, the heat roller 32 is rotated to feed out the sheet 14 by the width dimension 13X of the magnet 13. Then, a magnet 13 discharged from the magnet supply unit 34 is placed on the fed sheet 14, and the sheet 14 is adhered to the magnet 13. In this way, the feeding of the sheet 14 and the discharge of the magnets 13 are repeated, and the sheet 14 is adhered to all of the magnets 13 discharged from the magnet supply unit 34.

[0031] 3, it is determined whether or not the sheet 14 has been adhered to all of the magnets 13. If it is determined that the sheet 14 has been adhered to all of the magnets 13 (Yes), the flow ends. On the other hand, if it is determined that the sheet 14 has not been adhered to all of the magnets 13 (No), the process returns to step S13, where a magnet 13 to which a sheet has not yet been adhered is placed on a sheet 14, and the sheet 14 is adhered to the magnet 13 to which the sheet 14 has not yet been adhered.

[0032] Figure 4 is a perspective view showing the manufacturing process of the motor M shown in Figure 1, with (a) being a schematic diagram showing the member (magnet) insertion process, (b) being a schematic diagram showing the second heating process, and (c) being a schematic diagram showing the magnetization process. Figure 5 is a cross-sectional view showing the manufacturing process of the motor M shown in Figure 1, with (a) being a schematic diagram showing the member (magnet) insertion process, (b) being a schematic diagram showing the second heating process, and (c) being a schematic diagram showing the magnetization process. Figure 6 is a flowchart of the member (magnet) insertion process, second heating process, and magnetization process shown in Figures 4 and 5. Note that the following process explanation using Figure 5 will be described using an example in which the magnet 13 is adhered to the inner surface (outer surface in the depth direction) 121 of the slot hole 12 via the sheet 14.

[0033] After the sheet attachment step, as shown in step S7 of Fig. 6, magnets 13 are inserted into each slot hole 12 of the rotor core 10 (member insertion step). Specifically, as shown in Figs. 4(a) and 5(a), for example, magnets 13 having sheets 14 adhered to their outer surfaces 131, which are one end faces in the thickness direction, are inserted into the slot holes 12 of the rotor core 10. Here, a small gap C is formed between the magnets 13 inserted into the slot holes 12 and the inner surfaces 121 of the slot holes 12, as shown in Figs. 4(a) and 5(a).

[0034] Next, as shown in step S8 of FIG. 6 , the rotor core 10 into which the magnets 13 have been inserted in step S7 is placed in a drying oven (heating oven). Specifically, as shown in FIG. 4( b), for example, the rotor core 10 is placed in the drying oven (heating oven), and the rotor core 10 is heated, for example, by applying hot air H to the rotor core 10 (second heating step). Here, in the second heating step, the sheet 14 is heated to a second temperature T2 that is higher than the first temperature (50 to 90°C) and at which the sheet 14 expands and hardens to be able to adhere closely to the inner surfaces 121 of the slot holes 12. Specifically, the sheet 14 is heated to 130 to 190°C by heating the rotor core 10 with the hot air H.

[0035] As a result, as shown in step S9 of FIG. 6 , the sheet 14 expands and hardens, bonding the magnet 13 to the inner surface 121 of the slot hole 12. Specifically, the heating softens the thermosetting resin that makes up the sheet 14, and the foam component contained in the sheet 14 expands, causing the magnet 13 to expand in the thickness direction. Then, as shown in FIG. 5B , for example, inside the slot hole 12, the sheet 14 attached to the outer surface 131, which is one end face of the magnet 13 in the thickness direction, expands in the thickness direction of the magnet 13 (depth direction of the slot hole 12) to fill the gap C, causing the sheet 14 to adhere closely to the inner surface 121 of the slot hole 12 that faces the sheet 14. After that, as a certain amount of time passes, the thermosetting resin that makes up the sheet 14 hardens, bonding the magnet 13 to the inner surface 121 of the slot hole 12.

[0036] Thereafter, as shown in step S10 of Fig. 6, the magnets 13 inserted into the slot holes 12 of the rotor core 10 are magnetized (magnetization process), and the flow ends. Specifically, as shown in Figs. 4(c) and 5(c), for example, a magnetic field is generated and applied to the magnets 13, thereby magnetizing the magnets 13 attached to the slot holes 12 of the rotor core 10.

[0037] 7A to 7C are schematic diagrams showing how magnets 13 are inserted into slot holes 12 of a rotor core 10, where (a) shows a first mode, (b) shows a second mode, and (c) shows a third mode.

[0038] 7( a), so-called C-chamfers 136 are formed on both widthwise sides of one longitudinal end 135 of the magnet 13, which corresponds to the end of the magnet 13 in the insertion direction into the slot hole 12. As a result, when inserting the magnet 13 into the slot hole 12, the C-chamfers 136 guide the insertion of the magnet 13 into the slot hole 12, enabling good insertion of the magnet 13 into the slot hole 12.

[0039] 7(b), when inserting the magnets 13 into the slot holes 12 of the rotor core 10, for example, plate-shaped guide members GD are arranged on the opening edges on both sides in the width direction of the slot holes 12. As a result, when inserting the magnets 13 into the slot holes 12, the guide members GD guide the insertion of the magnets 13 into the slot holes 12, enabling good insertion of the magnets 13 into the slot holes 12.

[0040] 7(c), when inserting the magnet 13 into the slot hole 12 of the rotor core 10, the magnet 13 is held by a robot arm RA of a precision robot (not shown). This allows the magnet 13 to be accurately inserted into the slot hole 12 by the robot arm RA when inserting the magnet 13 into the slot hole 12, enabling good insertion of the magnet 13 into the slot hole 12.

[0041] 8A to 8D are diagrams showing the manner in which the magnets 13 are attached to the slot holes 12 of the rotor core 10, where (a) shows the first manner, (b) shows the second manner, (c) shows the third manner, and (d) shows the fourth manner.

[0042] As a first mode of adhesion of the magnet 13 to the slot hole 12 of the rotor core 10, for example, as shown in Figure 8 (a), the magnet 13 is adhered to the outer peripheral side of the rotor core 10, i.e., the outer surface 121 in the depth direction of the slot hole 12, via a sheet 14 attached to the outer surface 131, which is one end surface in the thickness direction.

[0043] In addition, as a second mode of adhesion of the magnet 13 to the slot hole 12 of the rotor core 10, for example, as shown in Figure 8 (b), the magnet 13 is adhered to the inner peripheral side surface of the rotor core 10, i.e., the inner surface 122 in the depth direction of the slot hole 12, via a sheet 14 attached to the outer surface 131, which is one end surface in the thickness direction.

[0044] As a third mode of adhesion of the magnet 13 to the slot hole 12 of the rotor core 10, for example, as shown in Figure 8 (c), the magnet 13 is adhered to both radial side surfaces of the rotor core 10, i.e., the outer surface 121 and inner surface 122 in the depth direction of the slot hole 12, via a sheet 14 attached to the outer surface 131, which is one end surface in the thickness direction.

[0045] As a fourth mode of adhesion of the magnet 13 to the slot hole 12 of the rotor core 10, for example, as shown in Figure 8 (d), the magnet 13 is adhered to both circumferential side surfaces of the rotor core 10, i.e., both widthwise side surfaces 123 and 124 of the slot hole 12, via each sheet 14 attached to both widthwise side surfaces 133 and 134.

[0046] (Effects of the Present Embodiment) As described above, the conventional method of bonding two members and the conventional method of manufacturing a motor require the labor of peeling off the release liners of the resin sheets attached to the magnets 13 when bonding the magnets 13 to the slot holes 12. This increases the manufacturing cost of the motor by the labor of peeling off the release liners, and there is still room for improvement.

[0047] In contrast, the method for bonding two components and the method for manufacturing a motor according to this embodiment achieves the following effects, thereby solving the problems of the conventional methods for bonding two components and the conventional methods for manufacturing a motor.

[0048] The method for bonding two members and the method for manufacturing a motor according to this embodiment include a first heating step in which a sheet 14, which exhibits adhesiveness and expandability when heated, is heated to a first temperature T1 at which the sheet 14 exhibits the adhesiveness; a sheet attachment step in which the sheet 14, which has been heated to the first temperature T1, is attached to a first member (magnet 13); a member insertion step in which the first member (magnet 13) to which the sheet 14 has been attached is inserted into an insertion hole (slot hole 12) provided in a second member (rotor core 10); and a second heating step in which the second member (rotor core 10) with the first member (magnet 13) inserted into the insertion hole (slot hole 12) is heated to a second temperature T2, which is higher than the first temperature T1 and at which the sheet 14 expands and hardens to adhere to the inner surfaces 121, 122, 123, and 124 of the insertion hole (slot hole 12).

[0049] As described above, in this embodiment, the sheet 14, which has been heated and made adhesive in the first heating step, is attached to the magnet 13, which is the first member. The magnet 13 is then inserted into the slot 12, which is the insertion hole of the rotor core 10, which is the second member. In the second heating step, the sheet 14 is heated together with the rotor core 10 to the second temperature T2, causing the sheet 14 to expand and harden, thereby adhering the magnet 13 to the inner surfaces 121, 122, 123, and 124 of the slot 12. In other words, in this embodiment, simply by causing the sheet 14 to become adhesive and expandable through heating, the magnet 13 can be adhered to the inner surfaces 121, 122, 123, and 124 of the slot 12. This eliminates the need for the labor required to peel off the release liner from the sheet, as in the conventional method, thereby reducing the labor required to adhere the magnet 13. Furthermore, eliminating the release liner has the advantage of reducing waste from the peeled release liner.

[0050] Furthermore, in this embodiment, the magnets 13 are adhered to the inner surfaces 121, 122, 123, and 124 of the slot holes 12 of the rotor core 10 via the sheets 14. This eliminates the risk of adhesive leakage compared to when an adhesive is applied to the magnets 13 and then adhered to the inner surfaces 121, 122, 123, and 124 of the slot holes 12 of the rotor core 10, and reduces the amount of work required to correct such leakage.

[0051] Furthermore, in this embodiment, the sheet 14 exhibits adhesiveness when heated. This allows the sheet 14 to be rolled and set, as in the sheet roll 140. By being able to roll the sheet 14 and set it as the sheet roll 140, it is possible to set a long length of the sheet 14 at once. This reduces the amount of sheet 14 refilling work or the number of times it is refilled, which contributes to improving motor productivity.

[0052] Additionally, in this embodiment, the sheet 14 exhibits adhesiveness upon heating, and does not have an inherent adhesive layer whose adhesion is restricted by a release liner as in the conventional method. In other words, the inherent adhesive layer in the sheet 14 is reduced, and the expansion layer can be increased accordingly. This allows the magnets 13 to be more firmly adhered and fixed to the inner surfaces 121, 122, 123, and 124 of each slot hole 12 in the rotor core 10, improving the reliability of the adhesion of the magnets 13.

[0053] In this embodiment, the first member is a magnet 13, and the second member is a rotor 1 of a motor M formed from laminated steel plates.

[0054] Therefore, the number of steps required for bonding the magnet 13 can be reduced, and the number of steps required for manufacturing the motor M can be reduced.

[0055] In this embodiment, the base material of the sheet 14 is a resin (thermosetting resin), and contains an expansion component.

[0056] In this embodiment, the expansion component contained in the sheet 14 causes the sheet 14 to expand, thereby filling the gaps C between the inner surfaces 121, 122, 123, and 124 of each slot hole 12 and the outer surfaces 131, 132, 133, and 134 of the magnets 13, and the sheet 14 comes into close contact with the inner surfaces 121, 122, 123, and 124 of each slot hole 12, thereby adhering the magnets 13 to the inner surfaces 121, 122, 123, and 124 of each slot hole 12. Therefore, in the member insertion step, the gaps C ensure easy insertion of the magnets 13 into each slot hole 12, and in the second heating step, the gaps C are filled by expansion based on the expansion component of the sheet 14, and the magnets 13 are easily adhered to the inner surfaces 121, 122, 123, and 124 of each slot hole 12 due to hardening of the resin (thermosetting resin) constituting the sheet 14. In other words, it is possible to easily insert the magnets 13 into each slot hole 12 and also to easily adhere the magnets 13 to the inner surfaces 121, 122, 123, and 124 of each slot hole 12. This makes the manufacturing process of the motor M easier and shortens the manufacturing process of the motor M.

[0057] In this embodiment, the sheet 14 is conveyed on rollers (roller conveyor 33).

[0058] In this manner, in this embodiment, the sheet 14 is placed on the roller conveyor 33 and transported, and in this embodiment, the sheet 14 is attached to the magnet 13 while being placed on the roller (roller conveyor 33).

[0059] In this manner, in this embodiment, the sheet 14 is attached to the magnet 13 while being placed on the roller conveyor 33. Therefore, the sheet 14 is attached to the magnet 13 while being supported (propped up) by the roller conveyor 33. This improves the adhesiveness of the sheet 14 to the magnet 13, making it possible to stably attach the sheet 14 to the magnet 13 and improving the reliability of the adhesion of the sheet 14 to the magnet 13.

[0060] In addition, in this embodiment, after the sheet attaching step of attaching the sheet 14 to the magnet 13, a sheet cutting step of cutting the sheet 14 is further included.

[0061] In this manner, in this embodiment, the sheet 14 is cut after being attached to the magnets 13. Therefore, when cutting the sheet 14, the sheet 14 is pressed against the roller conveyor 33 by the weight of the magnets 13, which has the advantage that the cutting operation of the sheet 14 can be performed relatively easily compared to when only the sheet 14 that has become adhesive due to the heating is cut first. This improves the ease of cutting the sheet 14 in the sheet cutting process, which can contribute to improving the productivity of the motor M.

[0062] In this embodiment, an example is given in which a gap is formed between the side of the magnet 13 to which the sheet 14 is not attached and the rotor core 10 (see, for example, Figures 5(a) and 8(a) and (b)), but this gap does not have to be present.

[0063] 9 and 10 show a second embodiment of the method for bonding two members and the method for manufacturing a motor according to the present invention, in which the second member according to the present invention is changed to the stator core 40 of a motor M. Note that the basic configuration other than this change is the same as in the first embodiment, and therefore the same components as in the first embodiment are denoted by the same reference numerals and description thereof will be omitted.

[0064] 9 is a schematic diagram of the motor M according to the present embodiment, showing the general configuration of the motor M. In addition, the direction along the rotation axis Z in FIG. 9 will be referred to as the "axial direction," the direction perpendicular to the rotation axis Z as the "radial direction," and the direction around the rotation axis Z as the "circumferential direction."

[0065] In this embodiment, the method for bonding two members and the method for manufacturing a motor according to the present invention are applied to the stator core 40 of the stator 4 that constitutes the motor M. Specifically, in this embodiment, the second member according to the present invention corresponds to the stator core 40 of the motor M, and as shown in Fig. 9, for example, the stator core 40 has a rotor accommodating portion 41 that penetrates in the axial direction in the center, and inside the stator core 40, a plurality of slot holes 42 that extend in the axial direction and correspond to the insertion holes according to the present invention are provided in parallel in the circumferential direction.

[0066] A rotor (not shown), which is a movable core, is rotatably accommodated in the rotor accommodating portion 41 via a predetermined gap. A coil 43, which corresponds to a first member according to the present invention, is inserted axially into each slot 42. Each slot 42 has a circumferential dimension 42X and a radial dimension 42Y that are slightly larger than a width dimension 43X and a thickness dimension 43Y of a sheet 44 (described later) that surrounds the outer periphery of the coil 43. In other words, before the coil 43 is inserted into each slot 42, i.e., before the sheet 44 (described later) is heated, a predetermined gap C is formed between inner surfaces 421, 423, and 424 of each slot 42 and the outer surface of the coil 43 (sheet 14) that faces the inner surfaces 421, 423, and 424.

[0067] The coil 43 includes a plurality of coils made of rectangular wire, such as a first coil 431 arranged on the outer periphery of the stator core 40 and a second coil 432 arranged on the inner periphery of the stator core 40, which are integrated with each other by adhesive or the like. The first coil 431 and the second coil 432 have the same configuration and are made of a well-known enameled wire having a copper wire 433 as a conductor and an insulating coating 434 made of, for example, enamel that surrounds the outer periphery of the copper wire 433. The first coil 431 and the second coil 432, arranged in parallel on the inside and outside in the radial direction, are insulating sheets, or sheets 14 that constitute so-called slot liners.

[0068] The sheet 14 has the same material and components as the sheet 14 according to the first embodiment and collectively surrounds the first coil 431 and the second coil 432. Specifically, the sheet 14 is attached to an outer peripheral surface 431a of the first coil 431, an inner peripheral surface 432b of the second coil 432, first side end faces 431c and 432c that are one side end faces of the first coil 431 and the second coil 432, and second side end faces 431d and 432d that are the other side end faces of the first coil 431 and the second coil 432. Here, the sheet 14 facing the generally tapered inner surface 422 of each slot hole 42 is not intended to bond to the inner surface 422 of each slot hole 42, but rather to insulate the coil 43 (second coil 432) from the stator core 40.

[0069] (Motor manufacturing process) Figure 10 is a cross-sectional view showing a method of adhering the coil 43 to the stator core 40 in the manufacturing process of the motor M shown in Figure 9, where (a) is a schematic diagram showing the sheet attachment process, (b) is a component (coil) insertion process, and (c) is a schematic diagram showing the second heating process.

[0070] 10A, the manufacturing process of the motor M according to this embodiment begins with adhering the first coil 431 and the second coil 432 constituting the coil 43 to one another so as to overlap in the thickness direction. Then, the sheet 14 is adhered to the outer peripheral surface 431a of the first coil 431, the inner peripheral surface 432b of the second coil 432, the first side end surfaces 431c, 432c of the first coil 431 and the second coil 432, and the second side end surfaces 431d, 432d of the first coil 431 and the second coil 432 by the same means as in the first embodiment (see FIG. 2).

[0071] 10(a) , for example, in a member (coil) insertion process shown in Fig. 10(b), the coils 43 (first coil 431 and second coil 432) with the sheet 14 adhered to the entire outer circumferential surface are inserted into the slot holes 42 of the stator core 40. Here, the coils 43 (first coil 431 and second coil 432) inserted into the slot holes 42 have a small gap C between them and the inner surfaces 421, 423, 424 of the slot holes 42, as shown in Fig. 10(b) .

[0072] 10(b), the stator core 40 with the coil 43 inserted therein is placed in a drying oven (heating oven) in a second heating step shown in FIG. 10(c). In the drying oven (heating oven), the stator core 40 is heated by, for example, blowing hot air H onto the stator core 40 (second heating step). In the second heating step, the sheet 14 is heated to a second temperature T2 (130 to 190°C) that is higher than the first temperature (50 to 90°C) and at which the sheet 14 expands and hardens to be able to adhere to the inner surface 121 of the slot hole 12.

[0073] 10( c), the sheet 14 expands and hardens, adhering the coil 43 to the inner surfaces 421, 423, and 424 of each slot hole 42. Specifically, the heating softens the thermosetting resin that makes up the sheet 14, and the foam component contained in the sheet 14 expands outward from the coil 43 to fill the gap C, causing the sheet 14 to adhere closely to the inner surfaces 421, 423, and 424 of each slot hole 42 that face the sheet 14. After that, after a certain period of time has passed, the thermosetting resin that makes up the sheet 14 hardens, adhering the coil 43 to the inner surfaces 421, 423, and 424 of each slot hole 42.

[0074] (Operation and Effect of the Present Embodiment) In the present embodiment, the first member is the coil 43, and the second member is the stator 4 of the motor M.

[0075] Thus, even when the method for bonding two members and the method for manufacturing a motor according to the present invention are applied to an embodiment in which the first member according to the present invention is the coil 43 and the second member is the stator 4 (stator core 40) of the motor M, it is possible to bond the coil 43 to the inner surfaces 421, 423, 424 of each slot hole 42 simply by causing the sheet 14 to exhibit its adhesiveness and expandability through heating. This eliminates the need for the labor required to peel off the release liner of the sheet as in the conventional method, reducing the labor required for bonding the coil 43 and reducing the labor required for manufacturing the motor M.

[0076] As described above, the present invention is not limited to the configurations and aspects exemplified in the above-described embodiments, and can be freely modified depending on the specifications, costs, etc. of the target object as long as the configuration can achieve the effects of the present invention described above.

Claims

1. A method for bonding two members, comprising: a first heating step in which a sheet that exhibits adhesiveness and expandability when heated is heated to a first temperature at which the sheet exhibits said adhesiveness; a sheet attachment step in which the sheet heated to the first temperature is attached to a first member; a member insertion step in which the first member to which the sheet has been attached is inserted into an insertion hole provided in a second member; and a second heating step in which the first member inserted into the insertion hole is heated to a second temperature which is higher than the first temperature and at which the sheet expands and hardens to adhere to the inner surface of the insertion hole.

2. A method for manufacturing a motor using the method for bonding two members as described in claim 1, characterized in that the first member is a magnet, and the second member is a rotor core of the motor formed from laminated steel plates.

3. A method for manufacturing a motor using the method for bonding two members as described in claim 1, characterized in that the first member is a coil, and the second member is a stator core of the motor.

4. A method for manufacturing a motor according to claim 2 or 3, characterized in that the base material of the sheet is a resin and contains an expansion component.

5. A method for manufacturing a motor using the method for bonding two members as described in claim 1, characterized in that the sheet is placed on a roller and transported.

6. A method of manufacturing a motor according to claim 5, characterized in that the sheet is attached to the first member while being placed on the roller.

7. A method for manufacturing a motor using the method for bonding two members as described in claim 1, further comprising a sheet cutting step of cutting the sheet after the sheet attaching step of attaching the sheet to the first member.

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