Method for manufacturing a motor core, motor core and motor with the motor core

Abstract

Provided are a motor core which can be effectively cooled and a motor with the motor core.In a preparatory step, through-holes are formed in first electromagnetic steel sheets constituting at least a portion of a plurality of electromagnetic steel sheets 100, and a coating layer 38 covering surfaces of the plurality of electromagnetic steel sheets 100 is formed; in a laminating step S4, the plurality of electromagnetic steel sheets 100 are laminated such that the through-holes of the first electromagnetic steel sheets communicate with each other and form a cooling channel 34 that allows passage of a cooling medium; and in a joining step S6, the adjacent electromagnetic steel sheets 100 are joined using the coating layer 38 such that the adjacent electromagnetic steel sheets 100 are sealed by the coating layer 38.

Description

Technical area

[0001] The present invention relates to a technology relating to a method for manufacturing a motor core and a motor having the motor core. General state of the art

[0002] Conventionally, technologies relating to a method for manufacturing a motor core and a motor having a motor core are known. An example of such a technology is disclosed in Patent Literature 1.

[0003] Patent Literature 1 describes a motor capable of cooling the coil of the motor by spraying oil onto the coil. Specifically, the motor housing described in Patent Literature 1 has an inner side surface provided with a circumferential oil passage having an annular shape extending along the circumferential direction of the motor. A member covering the circumferential oil passage (oil passage cover) is provided with a plurality of spray holes through which the oil circulating through the circumferential oil passage is sprayed onto the coil. With such a configuration, the coil is cooled by discharging the oil flowing through the circumferential oil passage onto the coil through the plurality of spray holes.

[0004] However, since the coil is cooled indirectly from the outside of the coil, the technology described in Patent Literature 1 is not sufficient to cool the motor core wound around the coil. Citation listPatent literature

[0005] Patent Document 1: JP 5347380 B Summary of the inventionTechnical problem

[0006] The present invention has been made in view of the above-described problem, and an object to be solved by the present invention is to provide a motor core which can be cooled effectively and a motor including the motor core. Solution to the problem

[0007] The problem to be solved by the present invention has been described above. Solutions to the problem will now be explained.

[0008] That is, a method for manufacturing a motor core according to the present invention corresponds to a method for manufacturing a motor core, the method comprising: a preparation step of preparing a plurality of electromagnetic steel sheets; a laminating step of laminating the plurality of thus prepared electromagnetic steel sheets;and a joining step for joining the plurality of thus laminated electromagnetic steel sheets. In the preparation step, through-holes are formed in first electromagnetic steel sheets constituting at least a part of the plurality of electromagnetic steel sheets, and a coating layer is formed covering surfaces of the plurality of electromagnetic steel sheets. In the laminating step, the plurality of electromagnetic steel sheets are laminated such that the through-holes of the first electromagnetic steel sheets communicate with each other and form a cooling channel allowing passage of a cooling medium. In the joining step, the adjacent electromagnetic steel sheets are joined using the coating layer so that the adjacent electromagnetic steel sheets are sealed by the coating layer.

[0009] In the lamination step, second electromagnetic steel sheets different from the first electromagnetic steel sheets are laminated from the plurality of electromagnetic steel sheets so as to sandwich the first electromagnetic steel sheets from both sides of the motor core in an axial direction.

[0010] Furthermore, each of the plurality of thus laminated electromagnetic steel sheets comprises: a body having an annular shape when viewed in the axial direction of the motor core, and a plurality of protrusion parts protruding radially inward or radially outward from the body in a comb-like shape, and the cooling channels include: circulation channels formed within the plurality of protrusion parts and circulating within the protrusion parts, and a connection channel formed in the body and connecting the adjacent circulation channels.

[0011] Furthermore, in the preparation step, the coating layer is applied to surfaces of the plurality of electromagnetic steel sheets.

[0012] Furthermore, in the preparation step, the coating layer is formed with a thickness of 25 micrometers or less.

[0013] Furthermore, in the joining step, the adjacent electromagnetic steel sheets are joined by vulcanization using the coating layer.

[0014] A motor core according to the present invention comprises a laminate of a plurality of electromagnetic steel sheets, the motor core further comprising: cooling channels formed by connecting through holes provided in at least a part of the plurality of electromagnetic steel sheets in a manner to communicate with each other and allowing passage of a cooling medium; and a coating layer connecting the adjacent electromagnetic steel sheets to provide sealing between the adjacent electromagnetic steel sheets.

[0015] A motor according to the present invention comprises a motor core manufactured by the above-described method for manufacturing a motor core or the above-described motor core. Advantageous effect of the invention

[0016] The present invention achieves the following advantageous effect.

[0017] In the present invention, the motor core can be effectively cooled. Short description of the figures Fig. 1 is a schematic side sectional view of a motor including a motor core according to the embodiment. Fig. 2 is a perspective view of the motor core. Fig. 3 is an exploded perspective view of the motor core. Fig. 4 is a flowchart illustrating a method for manufacturing a motor core. Fig. 5(a) is a front view showing a first electromagnetic steel sheet. Fig. 5(b) is a perspective view illustrating a first block and a seventh block corresponding to a laminate of the first electromagnetic steel sheets. Fig. 6(a) is a front view showing a second electromagnetic steel sheet. Fig. 6(b) is a perspective view illustrating a second block corresponding to a laminate of the second electromagnetic steel sheets. Fig. 7(a) is a front view showing a third electromagnetic steel sheet. Fig. 7(b) is a perspective view illustrating a third block corresponding to a laminate of the third electromagnetic steel sheets. Fig. 8(a) is a front view showing a fourth electromagnetic steel sheet. Fig. 8(b) is a perspective view showing a fourth block corresponding to a laminate of the fourth electromagnetic steel sheets. Fig. 9(a) is a front view showing a fifth electromagnetic steel sheet. Fig. 9(b) is a perspective view showing a fifth block corresponding to a laminate of the fifth electromagnetic steel sheets. Fig. 10(a) is a front view showing a sixth electromagnetic steel sheet. Fig. 10(b) is a perspective view showing a sixth block corresponding to a laminate of the sixth electromagnetic steel sheets. Fig. 11(a) is a sectional view showing the electromagnetic steel sheet with a coating layer formed thereon. Fig. 11(b) is a sectional view showing a laminate of the electromagnetic steel sheets. Fig. 12 is a perspective view showing an overall configuration of a cooling passage. Fig. 13 is a front view of the cooling channel and an enlargement of a part thereof. Fig. 14(a) is a perspective view showing how cooling water is supplied to the Fig. 13 shows an enlarged part. Fig. 14(b) is a figure showing cutouts showing the cooling channel in Fig. 13(a). Description of an embodiment

[0018] In the following description, the directions indicated by arrows U, D, F, B, L, and R in the figures are defined as an upward direction, a downward direction, a forward direction, a backward direction, a left direction, and a right direction, respectively. In each figure, the size, shape, and the like of the individual elements are exaggerated or understated for simplicity.

[0019] First, a configuration of a motor 1 including a motor core 3 according to a first embodiment of the present invention will be generally described with reference to FIG. Fig. 1 and Fig. 2 described.

[0020] The motor 1 according to the embodiment is used for a drive device on a motor vehicle (e.g., a hybrid vehicle (HV) or an electric vehicle (EV)). The motor 1 essentially includes a housing 2, a motor core 3, a coil 4, a rotor 5, and a rotating shaft 6.

[0021] The housing 2 is configured to accommodate the other elements of the motor 1 (such as the motor core 3). The motor core 3 is fixed to the inside of the housing 2. As shown in Fig. As shown in Figure 2, the motor core 3 has a substantially cylindrical shape. The motor core 3 is arranged so that its axis is aligned in the front-backward or longitudinal direction. The coil 4 is provided as a conductive wire wound around the motor core 3. The coil 4 has a cylindrical shape concentric with the motor core 3. The front and rear ends of the coil 4 are arranged to protrude from the front and rear ends of the motor core 3, respectively.

[0022] The rotor 5 has a substantially cylindrical shape. The rotor 5 is arranged on the inside of the motor core 3. The rotor 5 is arranged so that its axis is aligned in the longitudinal direction. The rotating shaft 6 is provided so that it passes through the center of the rotor 5, with its axis aligned in the longitudinal direction. The rotating shaft 6 is rotatably mounted on the housing 2 via a bearing. The rotor 5 and the rotating shaft 6 are arranged coaxially (concentrically) with the motor core 3 and the coil 4.

[0023] In the motor 1 configured as described above, when the coil 4 is energized, a magnetic field is generated in the motor core 3. When the magnetic field is generated in the motor core 3, the magnetic field generates a rotational force in the rotor 5, causing the rotor 5 and the rotating shaft 6 to rotate.

[0024] When the coil 4 is energized, the coil 4 heats up due to its internal resistance, and the temperature of the motor core 3 wound around the coil 4 also rises. Since the motor core 3 in this embodiment has a cooling structure, the motor core 3 (and consequently the coil 4) is cooled, making it less likely that problems (such as reduced efficiency) will occur.

[0025] A configuration of the engine core 3 will now be described with reference to the Fig. 2 and Fig. 3 described in detail.

[0026] The motor core 3 is formed as a laminate of a plurality of substantially ring-shaped electromagnetic steel sheets 100 (see, for example, Fig. 5) in the axial direction. Since the plurality of electromagnetic steel sheets 100 constituting the motor core 3 can be divided into a plurality of blocks in the axial direction, as will be described later, Fig. 2 For simplicity, boundaries between the blocks are shown. Fig. Figure 3 provides an exploded perspective view of the blocks. The motor core 3 includes a rear yoke 31, teeth 32, slots 33, and a cooling channel 34.

[0027] The rear yoke 31 has a substantially tubular shape. On the outer peripheral surface of the rear yoke 31, fastening portions 37 are provided, which protrude radially outward. The motor core 3 is fixed to the housing 2 via the fastening portions 37. Each of the fastening portions 37 has a hole extending through it in the axial direction, through which a screw (not shown) for tightening the motor core 3 is passed.

[0028] The teeth 32 protrude radially inward from the inner peripheral surface of the rear yoke 31. A plurality of the teeth 32 are provided and arranged at equal intervals with respect to each other in the circumferential direction.

[0029] The slots 33 are provided between the circumferentially adjacent teeth 32. A conductive wire is guided in each of the slots 33. The coil 4 is formed by winding the conductive wire guided through the slot 33 around the corresponding tooth 32.

[0030] The cooling channel 34 is a channel for a cooling medium (in this embodiment, water) for cooling the motor core 3. As shown in Fig. 3, through holes penetrating each of the blocks in the axial direction form the cooling channel 34 inside the motor core 3. A water inlet 35 leading to the cooling channel 34 and a water outlet 36 leading out of the cooling channel 34 are provided on the outer peripheral surface (in the embodiment, the upward outer peripheral surface on the front side in the axial direction) of the motor core 3. The configuration of the cooling channel 34 will be described in detail later.

[0031] A method of manufacturing the motor core 3 will now be described with reference to the Fig. 2 to 11.

[0032] In the embodiment, the method for manufacturing the motor core 3 includes a steel sheet punching step S1, a coating step S2, a drying step S3, a laminating step S4, a compression step S5, a joining step S6, and a vertical welding step S7.

[0033] As in Fig. 4, in the method for manufacturing the motor 1, the steel sheet punching step S1 is first performed. The steel sheet punching step S1 is a step of punching an electromagnetic steel sheet, which is a type of soft magnetic material. In the steel sheet punching step S1, for example, a coil strip is prepared, and a plurality of parts, each having a predetermined shape (hereinafter referred to as "electromagnetic steel sheets 100"), are manufactured by punching or pressing from the electromagnetic steel sheet corresponding to the unwound coil strip. The electromagnetic steel sheet 100 is manufactured in a substantially annular shape (see, for example, Fig. 5).

[0034] In the embodiment, a plurality of electromagnetic steel sheets 100 having different configurations (six types in the embodiment) are manufactured. These six types of electromagnetic steel sheets 100 have the same external shape but differ in the configurations (configurations and arrangements) of the through holes (cutouts) penetrating them in the thickness direction, as described later. Hereinafter, each of these six types of electromagnetic steel sheets 100 is sometimes referred to as a "first electromagnetic steel sheet 110," a "second electromagnetic steel sheet 120," a "third electromagnetic steel sheet 130," a "fourth electromagnetic steel sheet 140," a "fifth electromagnetic steel sheet 150," and a "sixth electromagnetic steel sheet 160."

[0035] The Fig. The first electromagnetic steel sheet 110 shown in Figure 5(a) is manufactured in a plurality (eight in the embodiment). Each of the first electromagnetic steel sheets 110 includes first screw fastening portions 111, first inner peripheral cutouts 112, a first body 118, and first protrusion portions 119.

[0036] The first screw fastening portions 111 are provided on the outer circumference in a manner that bulges radially outward. Three of the first screw fastening portions 111 are provided and arranged at equal intervals with respect to each other in the circumferential direction. A through hole (screw fastening hole) penetrating in the thickness direction is provided at each of the first screw fastening portions 111.

[0037] The first inner circumferential cutouts 112 are provided on the inner circumference in such a way that they penetrate the inner circumference in the thickness direction and extend radially outward. The plurality of first inner circumferential cutouts 112 are provided and arranged at equal intervals with respect to each other in the circumferential direction.

[0038] The first body 118 is a part of the first electromagnetic steel sheet 110, the part being located on the outside of the first inner peripheral cutout 112 in the radial direction. The first body 118 has an annular shape in the thickness direction.

[0039] The first protrusion portions 119 are portions that protrude radially inward from the first body 118 in the first electromagnetic steel sheet 110. By providing a plurality of the first protrusion portions 119, a comb-like shape is formed overall. Each of the first protrusion portions 119 is provided between the first inner peripheral cutouts 112, which are adjacent to each other in the circumferential direction.

[0040] The Fig. The second electromagnetic steel sheet 120 shown in Figure 6(a) is manufactured in a plurality (ten in the embodiment). Each of the second electromagnetic steel sheets 120 includes second screw fastening portions 121, second inner peripheral cutouts 122, second arcuate cutouts 123, a second body 128, and second protrusion portions 129.

[0041] Since the second screw fastening portions 121, the second inner peripheral cutouts 122, the second body 128, and the second protrusion parts 129 are configured in the same manner as the first screw fastening portions 111, the first inner peripheral cutouts 112, the first bodies 118, and the first protrusion parts 119 of the first electromagnetic steel sheet 110, respectively, their description will be omitted.

[0042] Each of the second arcuate cutouts 123 penetrates in the thickness direction and has an arcuate shape that opens radially inward in a front view. The second arcuate cutout 123 communicates with neither the outer circumference nor the inner circumference of the second electromagnetic steel sheet 120. Each of the second arcuate cutouts 123 has a radially inner end located near the inner circumference of the second electromagnetic steel sheet 120.

[0043] Each of the second arcuate cutouts 123 includes second legs 123a provided on respective second protrusion portions 129 adjacent to each other in the circumferential direction, and a second connecting portion 123b provided on the second body 128 in such a manner as to connect the radially outer ends of the two second legs 123a. As described above, the second arcuate cutout 123 is formed to span a corresponding one of the second inner circumferential cutouts 122 on its inner side in the thickness direction. A plurality of the second arcuate cutouts 123 are provided and arranged at equal intervals with respect to each other in the circumferential direction, except for an uppermost part of the second electromagnetic steel sheet 120.The second arcuate cutouts 123 are provided in a manner that each spans over every other second inner peripheral cutout 122 of the plurality of second inner peripheral cutouts 122 arranged in the circumferential direction.

[0044] The Fig. The third electromagnetic steel sheet 130 shown in Figure 7(a) is manufactured in a plurality (ten in the embodiment). Each of the third electromagnetic steel sheets 130 includes third screw fastening portions 131, third inner peripheral cutouts 132, third arcuate cutouts 133, third outer peripheral cutouts 134, a third body 138, and third protrusion portions 139.

[0045] Since the third screw fastening portions 131, the third inner peripheral cutouts 132, the third arcuate cutouts 133 (the third legs 133a and the third connecting portions 133b), the third body 138, and the third protrusion parts 139 are configured in the same manner as the first screw fastening portions 111 and the first inner peripheral cutouts 112 of the first electromagnetic steel sheets 110, the second arcuate cutouts 123 (the second legs 123a and the second connecting portions 123b) of the second electromagnetic steel sheets 120, the first body 118, and the first protrusion parts 119, respectively, description thereof will be omitted.

[0046] The third outer peripheral cutouts 134 are provided at an upper end of the third electromagnetic steel sheet 130 in a manner to penetrate the third electromagnetic steel sheet 130 in the thickness direction and extend radially inward from the outer periphery. Two of the third outer peripheral cutouts 134 are provided and arranged spaced apart from each other in the circumferential direction, with one of the third inner peripheral cutouts 132 interposed therebetween. Each of the third outer peripheral cutouts 134 has a radially inner end located near the inner periphery of the third electromagnetic steel sheet 130.

[0047] The Fig. The fourth electromagnetic steel sheet 140 shown in Figure 8(a) is manufactured in a plurality (twelve in the embodiment). Each of the fourth electromagnetic steel sheets 140 includes fourth screw fastening portions 141, fourth inner peripheral cutouts 142, fourth arcuate cutouts 143, fourth rectangular cutouts 145, a fourth body 148, and a fourth protrusion part 149.

[0048] Since the fourth screw fastening portions 141, the fourth inner peripheral cutouts 142, the fourth arcuate cutouts 143 (the fourth legs 143a and the fourth connecting portions 143b), the fourth body 148, and the fourth protrusion parts 149 are configured in the same manner as the first screw fastening portions 111 and the first inner peripheral cutouts 112 of the first electromagnetic steel sheet 110, the second arcuate cutouts 123 (the second legs 123a and the second connecting portions 123b) of the second electromagnetic steel sheet 120, the first body 118, and the first protrusion parts 119, respectively, description thereof will be omitted.

[0049] The fourth rectangular cutouts 145 are provided at the corresponding fourth protrusion portions 149. Each of the fourth rectangular cutouts 145 penetrates the fourth protrusion portions 149 in the thickness direction and has a substantially rectangular shape extending in the radial direction. The fourth rectangular cutout 145 communicates with neither the inner circumference nor the outer circumference of the fourth electromagnetic steel sheet 140. Two of the fourth rectangular cutouts 145 are provided and arranged at two corresponding fourth protrusion portions 149, which are adjacent to each other in the circumferential direction, in the upper part of the fourth electromagnetic steel sheet 140. Each of the fourth rectangular cutouts 145 has a radially inner end thereof located near the inner circumference of the fourth electromagnetic steel sheet 140.

[0050] The Fig. The fifth electromagnetic steel sheet 150 shown in Figure 9(a) is manufactured in a plurality (one hundred sixty-eight in the embodiment). Each of the fifth electromagnetic steel sheets 150 includes fifth screw fastening portions 151, fifth inner peripheral cutouts 152, fifth rectangular cutouts 155, a fifth body 158, and fifth protrusion portions 159.

[0051] Since the fifth screw fastening portions 151, the fifth inner peripheral cutouts 152, the fifth body 158, and the fifth protrusion parts 159 are configured in the same manner as the first screw fastening portions 111, the first inner peripheral cutouts 112, the first body 118, and the first protrusion parts 119 of the first electromagnetic steel sheet 110, their description will be omitted.

[0052] Each of the fifth rectangular cutouts 155 is configured in substantially the same manner as the fourth rectangular cutout 145 of the fourth electromagnetic steel sheet 140. However, unlike the fourth rectangular cutout 145, the fifth rectangular cutout 155 is provided on each of the fifth protrusion parts 159.

[0053] The Fig. The sixth electromagnetic steel sheets 160 shown in Figure 10(a) are manufactured in a plurality (thirty-two in the embodiment). Each of the sixth electromagnetic steel sheets 160 includes sixth bolt fastening portions 161, sixth inner peripheral cutouts 162, sixth arcuate cutouts 163, a sixth body 168, and sixth protrusion portions 169.

[0054] Since the sixth screw fastening portions 161, the sixth inner peripheral cutouts 162, the sixth body 168, and the sixth protrusion parts 169 are configured in the same manner as the first screw fastening portions 111, the first inner peripheral cutouts 112, the first body 118, and the first protrusion parts 119 of the first electromagnetic steel sheet 110, their description will be omitted.

[0055] The sixth arcuate cutouts 163 (the sixth legs 163a and the sixth connecting portions 163b) are configured in substantially the same manner as the second arcuate cutouts 123 (the second legs 123a and the second connecting portions 123b) of the second electromagnetic steel sheet 120. However, unlike the second arcuate cutouts 123, the sixth arcuate cutouts 163 are also provided at the uppermost part of the sixth electromagnetic steel sheet 160. The sixth arcuate cutouts 163 are arranged out of phase with the second arcuate cutouts 123 in the circumferential direction.Specifically, while the sixth legs 163a of the sixth arcuate cutouts 163 are provided in the circumferential direction at positions overlapping with the second legs 123a of the second arcuate cutouts 123, sixth connecting portions 163b of the sixth arcuate cutouts 163 are provided at positions offset from the second connecting portions 123b of the second arcuate cutouts 123 in the circumferential direction.

[0056] As in Fig. 4, after completion of the steel sheet punching step S1, the coating step S2 is carried out. The coating step S2 corresponds to a step for forming the coating layer 38, as shown in Fig. 11(a), by applying (forming a layer) a rubber material to the electromagnetic steel sheet 100. In the coating step S2, the coating is applied to both side surfaces of the electromagnetic steel sheet 100 in the thickness direction. The coating layer 38 is thus formed to cover the surfaces of the electromagnetic steel sheet 100.

[0057] As the coating method, various methods such as pre-coating, partial coating, and flow coating can be used. In the embodiment, partial coating is used. This allows the coating layer 38 to be formed in a layer thickness as thin as possible and to have a uniform thickness. In the embodiment, the coating layer 38 is formed with a layer thickness of 25 micrometers or less. Preferably, the coating layer 38 is formed with a thickness of 15 micrometers or less. More preferably, the coating layer 38 is formed with a thickness of 5 micrometers or less. An elastically deformable insulating material is used as the rubber material. This allows the rubber material to elastically deform to suppress the generation of noise and the like caused by vibrations of the engine 1.In this way, various rubber materials, such as fluorine and nitrile rubber, can be used as the rubber material.

[0058] In the coating step S2, the electromagnetic steel sheet 100 is cleaned as a preliminary process before coating. To increase the bonding strength between the electromagnetic steel sheet 100 and the coating layer 38, it is also possible to perform a chemical conversion treatment on both side surfaces of the electromagnetic steel sheet 100 in the thickness direction after cleaning the electromagnetic steel sheet 100, and to apply, for example, a primer after the chemical conversion treatment. Furthermore, it is possible to coat only one side surface of the electromagnetic steel sheet 100 instead of both side surfaces in the coating step S2.

[0059] After the coating step S2 is completed, the drying step S3 is performed. The drying step S3 is a step for drying the coating layer 38 formed in the coating step S2. In the drying step S3, the coating layer 38 is dried while the electromagnetic steel sheet 100 is kept at rest.

[0060] After completion of the drying step S3, the lamination step S4 is carried out as in Fig. 4. The lamination step is a step of laminating the electromagnetic steel sheets 100. In the lamination step, the motor core 3 is formed as a laminate of a predetermined number of electromagnetic steel sheets 100. In the motor core 3 according to the embodiment, for each of the six types, a predetermined number of the electromagnetic steel sheets 100 are laminated in a predetermined order, and the motor core 3 is divided into seven blocks in the lamination direction for convenience, as shown in FIGS. Fig. 2 and Fig. 3. Hereinafter, each of a plurality of blocks arranged sequentially in the lamination direction from the front side to the back side is sometimes referred to as "first block 100B," "second block 120B," "third block 130B," "fourth block 140B," "fifth block 150B," "sixth block 160B," and "seventh block 170B."

[0061] As in Fig. As shown in FIG. 5(b), each of the first block 100B and the seventh block 170B is formed as a laminate of the first electromagnetic steel sheets 110. In the embodiment, four first electromagnetic steel sheets 110 are laminated for each of the first block 100B and the seventh block 170B. Thus, each of the first block 100B and the seventh block 170B has a thickness of, for example, 1 mm. In the first block 100B, the first screw fastening portions 111, the first inner peripheral cutouts 112, the first bodies 118, and the first protrusion parts 119 are stacked to overlap each other in the lamination direction.

[0062] As in Fig. As shown in Fig. 6(b), the second block 120B is formed as a laminate of the second electromagnetic steel sheets 120. In the embodiment, ten second electromagnetic steel sheets 120 are laminated for the second block 120B. As a result, the second block 120B has a thickness of, for example, 2.5 mm. In the second block 120B, the second screw fastening portions 121, the second inner peripheral cutouts 122, the second arcuate cutouts 123, the second bodies 128, and the second protrusion parts 129 are stacked overlapping each other in the lamination direction.

[0063] As in Fig. As shown in Figure 7(b), the third block 130B is formed as a laminate of third electromagnetic steel sheets 130. In the embodiment, ten third electromagnetic steel sheets 130 are laminated in the third block 130B. As a result, the third block 130B has a thickness of, for example, 2.5 mm. In the third block 130B, the third screw fastening portions 131, the third inner peripheral cutouts 132, the third arcuate cutouts 133, the third outer peripheral cutouts 134, the third bodies 138, and the third protrusion parts 139 are stacked to overlap each other in the lamination direction.

[0064] As in Fig. As shown in Fig. 8(b), the fourth block 140B is formed as a laminate of the fourth electromagnetic steel sheets 140. In the embodiment, twelve fourth electromagnetic steel sheets 140 are laminated in the fourth block 140B. As a result, the fourth block 140B has a thickness of, for example, 3 mm. In the fourth block 140B, the fourth screw fastening portions 141, the fourth inner peripheral cutouts 142, the fourth arcuate cutouts 143, the fourth rectangular cutouts 145, the fourth bodies 148, and the fourth protrusion parts 149 are stacked to overlap each other in the lamination direction.

[0065] As in Fig. As shown in Figure 9(b), the fifth block 150B is formed as a laminate of the fifth electromagnetic steel sheets 150. In the embodiment, one hundred sixty-eight fifth electromagnetic steel sheets 150 are laminated in the fifth block 150B. As a result, the fifth block 150B has a thickness of, for example, 42 mm. In the fifth block 150B, the fifth screw fastening portions 151, the fifth inner peripheral cutouts 152, the fifth rectangular cutouts 155, the fifth bodies 158, and the fifth protrusion parts 159 are stacked so as to overlap each other in the lamination direction.

[0066] As in Fig. As shown in Figure 10(b), the sixth block 160B is formed as a laminate of the sixth electromagnetic steel sheets 160. In the embodiment, thirty-two sixth electromagnetic steel sheets 160 are laminated in the sixth block 160B. As a result, the sixth block 160B has a thickness of, for example, 8 mm. In the sixth block 160B, the sixth bolt fastening portions 161, the sixth inner peripheral cutouts 162, the sixth arcuate cutouts 163, the sixth bodies 168, and the sixth protrusion parts 169 are stacked to overlap each other in the lamination direction.

[0067] As a result of assembling the motor core 3 in the manner described above, the rear yoke 31, the teeth 32, the slots 33, and the cooling channel 34 of the motor core 3 are formed by the corresponding parts of the blocks stacked one on top of the other in the lamination direction. Specifically, the rear yoke 31 is formed by stacking the bodies 118, 128, 138, 148, 158, and 168 of the respective blocks. The fastening portion 37 is formed by stacking the screw fastening portions 111, 121, 131, 141, 151, and 161.

[0068] The teeth 32 are formed by stacking the protrusions 119, 129, 139, 149, 159, and 169 of the respective blocks. The slots 33 are formed by the overlapping inner peripheral cutouts 112, 122, 132, 142, 152, and 162 of the respective blocks.

[0069] The overlapping arcuate cutouts 123, 133, 143, 163, the overlapping outer peripheral cutouts 134 and the overlapping rectangular cutouts 145, 155 of the respective blocks communicate with each other and together form the cooling channel 34. The configuration of the cooling channel 34 will be described in detail later.

[0070] As in Fig. As shown in Fig. 4, after the completion of the lamination step S4, the compression step S5 is performed. The compression step S5 is a step of compressing the entire laminated electromagnetic steel sheets 100 (from the first block 100B to the seventh block 170B) in the lamination direction. In the compression step S5, the entire laminated electromagnetic steel sheets 100 are pressed inward in the lamination direction using, for example, a predetermined clamp. As described above, the coating layer 38 in the embodiment has a layer thickness of 25 micrometers or less (that is, it is relatively thin). Therefore, even when the laminated electromagnetic steel sheets 100 are compressed, the coating layer 38 is less likely to come out or leak from between the electromagnetic steel sheets 100.

[0071] As in Fig. 4, after performing the compression step S5, the joining step S6 is performed. The joining step S6 is a step of joining the electromagnetic steel sheets 100 that are adjacent to each other in the lamination direction. The joining step S6 is performed while the entire laminated electromagnetic steel sheets 100 are compressed. In the embodiment, in the joining step S6, the adjacent electromagnetic steel sheets 100 are joined by vulcanization bonding using the coating layer 38. As a result, as shown in Fig. As shown in Figure 11(b), the adjacent press-bonded electromagnetic steel sheets 100 are bonded in close contact with each other, and the entire laminated electromagnetic steel sheets 100 (from the first block 100B to the seventh block 170B) are thereby integrated. In the bonding step S6, the entire surfaces of the adjacent electromagnetic steel sheets 100 that are adjacent to each other can be sealed because the coating layer 38 is used as an adhesive.

[0072] As in Fig. 4, after the joining step S6 is completed, the vertical welding step S7 is performed. In the vertical welding step S7, a weld line (not shown) is formed on the outer periphery of the electromagnetic steel sheets 100 integrated in the joining step S6 in a manner extending in the lamination direction. The weld line is formed at a plurality of points spaced apart from each other in the circumferential direction. In this way, the strength of the motor core 3 can be increased, and the entire electromagnetic steel sheets 100 can be kept compressed. Once the joining step S6 is completed, the finished motor core 3 is achieved.

[0073] A configuration of the cooling channel 34 will now be described with reference to Fig. 3 and the Fig. 12 to 14 described in detail.

[0074] As in Fig. As shown in FIG. 3, the cooling passage 34 is formed inside the blocks between the first block 110B and the seventh block 170B in the engine core 3. That is, the cooling passage 34 is formed by positioning the first block 110B and the seventh block 170B from the front and rear, respectively, in such a manner as to sandwich the through holes (cutouts) axially penetrating the blocks between the first block 110B and the seventh block 170B. The thus-formed cooling passage 34 has a substantially cylindrical shape whose axial direction is aligned in the longitudinal direction. The cooling passage 34 includes front arcuate passages 310, rear arcuate passages 320, main passages 330, an introduction passage 340, and an exhaust passage 350.

[0075] The front arcuate channels 310 forming the cooling channel 34 are channels arranged at the front end. Each of the front arcuate channels 310 has an arcuate shape that opens radially inward when viewed from the front. The front sides of the front arcuate channels 310 are closed by the first block 110B (see Fig. 3). As in Fig. 14, the front arcuate channels 310 are formed by the overlapping arcuate cutouts 123, 133, 143 on the second, third and fourth blocks 120B, 130B, 140B.

[0076] The legs 123a, 133a, 143a of the arcuate cutouts 123, 133, 143 provide the channels formed inside the respective teeth 32 (hereinafter referred to as "front arcuate first channels 311"). The connecting portions 123b, 133b, 143b of the arcuate cutouts 123, 133, 143 provide the channels formed inside the rear yoke 31 (hereinafter referred to as "front arcuate second channels 312").

[0077] The rear arcuate channels 320 forming the cooling channel 34 are channels located at the rear end. Each of the rear arcuate channels 320 has an arcuate shape that opens radially inward when viewed from the front. The rear sides of the rear arcuate channels 320 are closed by the seventh block 170B (see Fig. 3). The rear arcuate channels 320 are formed by the overlapping sixth arcuate cutouts 163 of the sixth block 160B.

[0078] The sixth legs 163a of the sixth arcuate cutouts 163 provide the channels formed inside the teeth 32 (hereinafter referred to as "rear arcuate first channels 321"). The sixth connecting portions 163b of the sixth arcuate cutouts 163 provide the channels formed inside the rear yoke 31 (hereinafter referred to as "rear arcuate second channels 322").

[0079] The main channels 330 forming the cooling channel 34 are channels located between the front arcuate channels 310 and the rear arcuate channels 320. Each of the main channels 330 is formed to connect the front arcuate channel 310 and the corresponding rear arcuate channel 320. The main channels 330 are formed to extend linearly in the axial direction. The main channels 330 are formed by the overlapping rectangular cutouts 145, 155 (not shown) in the fourth and fifth blocks 140B, 150B.

[0080] In this way, the main channels 330 are provided inside all the teeth 32 near the inner peripheral surface of the motor core 3. Each of the main channels 330 is provided in a manner extending substantially in the axial direction between the front end and the rear end of the corresponding tooth 32. Specifically, the main channels 330 are formed to extend in the axial direction across the teeth 32 of the respective blocks, except for the teeth 32 in the first block 110B and the seventh block 170B.

[0081] Each of the main channels 330 has the front end connected to the corresponding front arcuate first channel 311. Each of the main channels 330 has the rear end connected to the corresponding rear arcuate first channel 321. Of the plurality of main channels 330, two uppermost front ends have connected to both an inlet channel 340 and an outlet channel 350 (not shown).

[0082] The introduction channel 340 is a channel for introducing cooling water into the cooling channel 34. The introduction channel 340 is configured to connect the water inlet 35 located on the outer peripheral surface of the motor core 3 with one of the two main channels 330 in the uppermost part (the left one in the figure). The introduction channel 340 is formed by one of the two overlapping outer peripheral cutouts 134 in the third block 130B (the left one in the figure).

[0083] The outlet channel 350 is a channel for discharging the cooling water from the cooling channel 34. The outlet channel 350 is configured to connect the water outlet 36 located on the outer peripheral surface of the motor core 3 with the other main channel 330 among the two main channels 330 in the uppermost part (the right one in the figure). The outlet channel 350 is formed by the other of the two overlapping outer peripheral cutouts 134 in the third block 130B (the right one in the figure).

[0084] In this way, the cooling channel 34, especially with the front arcuate channels 310, the rear arcuate channels 320 and the main channels 330, presents a meandering shape (extending back and forth) in the longitudinal direction since the cooling channel 34 extends in the circumferential direction, and these are provided so that all the teeth 32 are covered thereby.

[0085] With reference to Fig.14(a), it will now be described how the cooling water flows through the cooling channel 34 configured as described above.

[0086] First, the cooling water introduced from the introduction channel 340 is guided backward through the main channel 330. At the rear end of the main channel 330, the cooling water is guided to one of the rear arcuate first channels 321 in the rear arcuate channel 320, and sequentially guided to the rear arcuate second channel 322 and the other rear arcuate first channel 321 in the rear arcuate channel 320, and then guided to the main channel 330, which is offset by one channel in the circumferential direction (counterclockwise). The cooling water is then guided forward along the main channel 330.

[0087] At the front end of the main channel 330, the cooling water is guided to one of the front arcuate first channels 311 in the front arcuate channel 310, then sequentially guided to the front arcuate second channel 312 and the other front arcuate first channel 311 in the front arcuate channel 310, and then guided to the main channel 330 offset by one channel in the circumferential direction (counterclockwise). The cooling water is then guided backward along the main channel 330.

[0088] In this way, the cooling water introduced from the introduction channel 340 is guided to the front or rear within each of the teeth 32, guided in the axial direction in such a way that it describes substantially a complete circle around the motor core 3, and then reaches the outlet channel 350. Thus, the teeth 32, which correspond to the part that is most likely to be heated in the motor core 3, can be effectively cooled.

[0089] As described above, a method for manufacturing a motor core 3 according to the embodiment corresponds to a method for manufacturing a motor core 3, the method comprising: a preparation step for preparing a plurality of electromagnetic steel sheets 100 (a steel sheet punching step S1, a coating step S2, and a drying step S3); a laminating step S4 for laminating the plurality of thus-prepared electromagnetic steel sheets 100; and a joining step S6 for joining the plurality of thus-laminated electromagnetic steel sheets 100. In the preparation step, through holes (arc-shaped cutouts 123, 133, 143, 163, outer peripheral cutouts 134, rectangular cutouts 145, 155) are formed in first electromagnetic steel sheets (second electromagnetic steel sheets 120, third electromagnetic steel sheets 130, fourth electromagnetic steel sheets 140,Fifth electromagnetic steel sheets 150 and sixth electromagnetic steel sheets 160) are formed, which are at least a part of the plurality of electromagnetic steel sheets 100, and a coating layer 38 covering surfaces of the plurality of electromagnetic steel sheets 100 is formed. In the laminating step S4, the plurality of electromagnetic steel sheets 100 are laminated such that the through-holes of the first electromagnetic steel sheets communicate with each other and form a cooling channel 34 that allows the passage of a cooling medium. In the joining step S6, the adjacent electromagnetic steel sheets 100 are joined using the coating layer 38, so that the adjacent electromagnetic steel sheets 100 are sealed by the coating layer 38.

[0090] In the motor core 3 manufactured using such a configuration, the motor core 3 can be effectively cooled from the inside by using the cooling channel 34 formed by laminating the plurality of electromagnetic steel sheets 100.

[0091] In the embodiment, since the adjacent electromagnetic steel sheets 100 are bonded using the coating layer 38 and the adjacent electromagnetic steel sheets 100 are sealed by the coating layer 38, it is possible to prevent the cooling medium flowing through the cooling channel 34 from leaking to the outside of the motor core 3. In this way, since dispersion of the cooling medium from the motor core 3 into the motor 1 is prevented, friction loss due to the dispersed cooling medium, for example, can be avoided.

[0092] In the method for manufacturing the motor core 3, in the laminating step S4, second electromagnetic steel sheets (the first electromagnetic steel sheets 110) different from the first electromagnetic steel sheets are laminated from the plurality of electromagnetic steel sheets 100 so as to sandwich the first electromagnetic steel sheets from both sides of the motor core 3 in the axial direction.

[0093] In such a configuration, one axial side and the other axial side of the cooling channel 34 can be defined using the first electromagnetic steel sheets 110 constituting the motor core 3.

[0094] That is, since it is not necessary to provide a special member or the like for defining the cooling channel 34, it is possible to achieve cost reduction and simplify the configuration.

[0095] In the method for manufacturing the motor core 3, each of the plurality of laminated electromagnetic steel sheets 100 includes: a body (bodies 118 to 168) having an annular shape when viewed in the axial direction of the motor core 3; and a plurality of protrusion portions (protrusion portions 119 to 169) protruding radially inward or radially outward from the body in a comb-like shape, and the cooling channel 34 includes: circulation channels (main channels 330, front arcuate first channels 311, rear arcuate first channels 321) formed within the plurality of protrusion portions and circulating within the protrusion portions; and a connection channel (front arcuate second channel 312, rear arcuate second channel 322) formed in the body and connecting the adjacent circulation channels.

[0096] With such a configuration, the teeth 32 corresponding to the part which is most likely to be heated in the motor core 3 can be effectively cooled.

[0097] In the method for manufacturing the motor core 3, in the preparation step (coating step S2), the coating layer 38 is applied to surfaces of the plurality of electromagnetic steel sheets 100.

[0098] With such a configuration, the tightness provided by the coating layer 38 can be improved.

[0099] In the method of manufacturing the motor core 3, the coating layer 38 is formed in the preparation step (coating step S2) to a thickness of 25 micrometers or less.

[0100] Since the coating layer 38 is relatively thin in such a configuration, the coating layer 38 is less likely to leak out between the electromagnetic steel sheets 100 even if the laminated electromagnetic steel sheets 100 are compressed.

[0101] In the method for manufacturing the motor core 3, in the joining step S6, the adjacent electromagnetic steel sheets 100 are joined by vulcanization using the coating layer 38.

[0102] With such a configuration, the entire surface between the adjacent electromagnetic steel sheets 100 can be effectively sealed.

[0103] A motor core 3 according to the embodiment corresponds to a motor core 3 having a laminate of a plurality of electromagnetic steel sheets 100, the motor core 3 including: a cooling channel 34 formed by connecting through holes provided on at least a part of the plurality of electromagnetic steel sheets 100 in a communicating manner, and allowing the passage of a cooling medium; and a coating layer 38 connecting the adjacent electromagnetic steel sheets 100 to provide sealing between the adjacent electromagnetic steel sheets 100.

[0104] With such a configuration, the motor core 3 can be effectively cooled from the inside by using the cooling channel 34 formed by laminating the plurality of electromagnetic steel sheets 100.

[0105] A motor 1 according to the embodiment includes a motor core 3 manufactured by the method for manufacturing the motor core 3 according to any one of claims 1 to 6, or the motor core 3 according to claim 7.

[0106] With such a configuration, by using the cooling channel 34 formed by laminating the plurality of electromagnetic steel sheets 100, the motor core 3 can be effectively cooled from the inside.

[0107] Although the embodiment of the present invention has been described above, the present disclosure is not limited to the above-described configurations, and various modifications may be made within the scope of the present invention defined in the claims.

[0108] For example, in the embodiment, vulcanization bonding is used in the bonding step S6, but the embodiment is not limited to this. In the bonding step S6, the adjacent electromagnetic steel sheets 100 can be bonded to each other using any method.

[0109] In the embodiment, one water inlet 35 leading to the cooling channel 34 and one water outlet 36 leading from the cooling channel 34 are provided, but a plurality of water inlets (corresponding to one cooling channel 34) may be provided. Furthermore, the water inlet 35 and the water outlet 36 may be provided at any location on the motor core 3. In the embodiment, only one cooling channel 34 is provided, but a plurality of cooling channels may be provided. In the embodiment, the plurality of protrusions (the first protrusion part 119 and the like) protrude radially inward, but the plurality of protrusions may also protrude radially outward.

[0110] In the embodiment, the main channels 330 of the cooling channel 34 are formed to extend in the axial direction substantially between the front end and the rear end of the teeth 32 (that is, so that the entire layer can be cooled), but the embodiment is not limited to this. That is, the main channels 330 may be partially provided in the axial direction between the front end and the rear end of the teeth 32 (that is, in a manner that enables partial layer cooling). Specifically, the main channels 330 may be provided only at a front part or a rear part of the teeth 32. Furthermore, the main channels 330 may be provided only at a central portion of the teeth 32 in the longitudinal direction.

[0111] That is, since the cooling channel 34 is formed by forming cutouts within the teeth 32, the formation of the magnetic field may be hindered. Therefore, it is possible to use a shape that can effectively cool, depending on the specifications of the motor 1, without excessively hindering the formation of the magnetic field.

[0112] Note that the motor core according to the present invention is not limited to that according to the embodiment and may correspond to a core used in either a rotor or a stator of a motor (that is, a rotor core or a stator core). Industrial applicability

[0113] The present invention is applicable to a method for manufacturing a motor core, a motor core, and a motor having the motor core. List of reference symbols 34 Cooling channel 38 coating layer 100 Electromagnetic steel sheet S1 steel sheet punching step S2 coating step S3 Drying step S4 Laminating step S6 connection step QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 5347380 B

[0005]

Claims

[1] A method of manufacturing a motor core, the method comprising: a preparation step of preparing a plurality of electromagnetic steel sheets; a laminating step for laminating the plurality of electromagnetic steel sheets thus prepared; and a joining step of joining the plurality of thus laminated electromagnetic steel sheets, wherein in the preparation step, through holes are formed in first electromagnetic steel sheets constituting at least a part of the plurality of electromagnetic steel sheets, and a coating layer covering surfaces of the plurality of electromagnetic steel sheets is formed, in the laminating step, the plurality of electromagnetic steel sheets are laminated such that the through holes of the first electromagnetic steel sheets communicate with each other and form a cooling channel that allows passage of a cooling medium, and in the joining step, the adjacent electromagnetic steel sheets are joined using the coating layer so that the adjacent electromagnetic steel sheets are sealed by the coating layer. [2] A method for manufacturing a motor core according to claim 1, wherein in the laminating step, second electromagnetic steel sheets different from the first electromagnetic steel sheets are laminated from the plurality of electromagnetic steel sheets so as to sandwich the first electromagnetic steel sheets from both sides of the motor core in an axial direction. [3] A method of manufacturing a motor core according to claim 1, wherein each of the plurality of electromagnetic steel sheets thus laminated comprises a body having a ring-shaped shape when viewed in the axial direction of the motor core, and a plurality of projection parts projecting radially inwardly or radially outwardly from the body in a comb-like shape, and the cooling channels include Circulation channels formed within the plurality of projection parts and circulating within the projection parts, and a connecting channel formed in the body that connects the adjacent circulation channels. [4] A method for manufacturing a motor core according to claim 1, wherein in the preparation step, the coating layer is applied to surfaces of the plurality of electromagnetic steel sheets. [5] A method for manufacturing a motor core according to claim 1, wherein in the preparation step, the coating layer is formed to have a thickness of 25 micrometers or less. [6] A method of manufacturing a motor core according to claim 1, wherein in the joining step, the adjacent electromagnetic steel sheets are joined by vulcanization using the coating layer. [7] A motor core comprising a laminate of a plurality of electromagnetic steel sheets, the motor core further comprising: Cooling channels formed by connecting through holes provided on at least a part of the plurality of electromagnetic steel sheets in a communicating manner, and allowing passage of a cooling medium; and a coating layer bonding the adjacent electromagnetic steel sheets to provide a seal between the adjacent electromagnetic steel sheets. [8] A motor having a motor core manufactured by the method for manufacturing a motor core according to any one of claims 1 to 6, or the motor core according to claim 7.

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