Drive device

Abstract

The drive devices (1-3) each comprise a motor (10), a motor case (21, 22), and a frame member (25, 26). The motor (10) comprises: a stator (11); a motor winding (12) that is wound around the stator (11); a rotor (13) that is provided so as to be rotatable relative to the stator (11) by energization of the motor winding (12); and a shaft (15) that rotates integrally with the rotor (13). The motor case (21, 22) of a non-metal material has a cylindrical part (211) and holds the stator (11). The frame member (25, 26) of a non-metal material is provided on one side of the cylindrical part (211) in the axial direction. The frame member (25, 26) abuts an end surface (212, 226) of an axial direction side of the motor case (21, 22) and is welded at the abutment surface.

Description

Drive unit CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Patent Application No. 2024-025142, filed on February 22, 2024, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a drive device.

[0003] 2. Description of the Related Art Conventionally, there has been known a drive device including a motor unit and a control unit. For example, in Patent Document 1, a motor case that houses the motor unit and a control unit cover that covers the control unit are integrally provided.

[0004] Japanese Patent Application Laid-Open No. 2016-72996

[0005] In Patent Document 1, the motor case and the lid that fits onto the cylindrical portion of the motor case are made of metal, and the motor case and the control unit cover are sealed by being fixed with an adhesive. A motor case made of metal may corrode due to exposure to water, humidity, etc. An object of the present disclosure is to provide a drive device that can improve corrosion resistance.

[0006] The drive device of the present disclosure includes a motor, a motor case, and a frame member. The motor has a stator, motor windings wound around the stator, a rotor that is rotatable relative to the stator when current is applied to the motor windings, and a shaft that rotates integrally with the rotor.

[0007] The motor case, made of a non-metallic material, has a cylindrical portion and holds the stator. The frame member, made of a non-metallic material, is provided on one axial side of the cylindrical portion. The frame member abuts against the axial end face of the motor case and is welded to the abutting surface. This improves corrosion resistance.

[0008] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which Fig. 1 is a schematic diagram showing an electric power steering device according to a first embodiment, Fig. 2 is a cross-sectional view of a drive unit according to the first embodiment, Fig. 3 is a plan view showing a state in which a frame member is assembled to a motor case in the first embodiment, Fig. 4 is a plan view showing a state in which the frame member is assembled to the motor case in the first embodiment, Fig. 5 is an explanatory diagram explaining welding of the motor case and the frame member according to the first embodiment, Fig. 6 is a cross-sectional view of a drive unit according to a second embodiment, and Fig. 7 is a cross-sectional view of a drive unit according to a third embodiment.

[0009] A drive device according to the present disclosure will be described below with reference to the drawings. In the following, substantially identical components in multiple embodiments will be assigned the same reference numerals and descriptions thereof will be omitted.

[0010] (First embodiment) The first embodiment is shown in Figures 1 to 5. A drive device 1 includes a motor 10 and an ECU 30 as a control unit, and is applied to an electric power steering device 8, which is a steering device for assisting the steering operation of a vehicle. Figure 1 shows the overall configuration of a steering system 90 that includes the electric power steering device 8. The steering system 90 includes a steering wheel 91, which is a steering member, a steering shaft 92, a pinion gear 96, a rack shaft 97, wheels 98, the electric power steering device 8, etc.

[0011] The steering wheel 91 is connected to a steering shaft 92. A torque sensor 93 that detects steering torque is provided on the steering shaft 92. A pinion gear 96 is provided at the tip of the steering shaft 92. The pinion gear 96 meshes with a rack shaft 97. A pair of wheels 98 are connected to both ends of the rack shaft 97 via tie rods or the like.

[0012] When the driver turns the steering wheel 91, the steering shaft 92 connected to the steering wheel 91 rotates. The rotational motion of the steering shaft 92 is converted into linear motion of a rack shaft 97 by a pinion gear 96. A pair of wheels 98 are steered to an angle corresponding to the amount of displacement of the rack shaft 97.

[0013] The electric power steering device 8 includes the drive unit 1 and a reduction gear 89 as a power transmission unit that reduces the rotation of the motor 10 and transmits the reduced rotation to the rack shaft 97. The electric power steering device 8 of this embodiment is a so-called "rack assist type," but may also be a so-called "column assist type" that transmits the rotation of the motor 10 to the steering shaft 92.

[0014] The motor 10 is a three-phase brushless motor having two sets of three-phase windings. The motor 10 outputs part or all of the torque required for steering, and is driven by power supplied from a vehicle power supply (not shown) to rotate the reduction gear 89 forward and reverse.

[0015] A connector 41 provided on the ECU 30 is connected to a vehicle power supply to receive power, a vehicle communication network to input and output communication signals, and a torque sensor 93 to input a sensor signal.

[0016] As shown in FIG. 2, the drive unit 1 has the ECU 30 integrally provided on one side of the motor 10 in the axial direction, which is a so-called "mechatronically integrated type," but they may also be separate. The mechatronically integrated type allows the motor 10 and ECU 30 to be efficiently arranged in a vehicle with limited installation space. Hereinafter, the axial direction of the motor 10 will be considered to be the axial direction of the drive unit 1, and will be simply referred to as the "axial direction." The same applies to the "radial direction" and "circumferential direction." Furthermore, in the drive unit 1, the side opposite the ECU 30 will be referred to as the "front side," and the ECU 30 side will be referred to as the "rear side." Note that FIG. 2 is a view corresponding to the cross section taken along line II-II in FIG. 3.

[0017] The motor 10 includes a stator 11, motor windings 12, a rotor 13, a shaft 15, a motor case 21, and a frame member 25. The stator 11 is formed of a laminated iron plate or the like, and has the motor windings 12 wound thereon. One end of the motor windings 12 extends to the ECU 30 side and is electrically connected to a substrate 31. The motor windings 12 and the substrate 31 may be connected via a separate member such as a bus bar.

[0018] The rotor 13 is made of, for example, laminated steel plates, and is disposed radially inside the stator 11 so as to be rotatable relative to the stator 11. A shaft 15 is press-fitted into the rotor 13. The shaft 15 is rotatably supported by bearings 151 and 152. When current is applied to the motor windings 12, the rotor 13 and the shaft 15 rotate together. A magnet 16 is fixed to the rear end of the shaft 15.

[0019] The motor case 21 is formed in a generally cylindrical shape with a bottom that opens toward the ECU 30. The motor case 21 has a cylindrical portion 211, a bottom portion 213, and a flange portion 214 that are integrally formed from a non-metallic material such as resin.

[0020] The stator 11 and motor windings 12 are integrally molded into the cylindrical portion 211. By integrally molding the stator 11 and motor windings 12 with the non-metallic motor case 21, corrosion and deterioration of sealing due to water (especially salt water) and humidity can be prevented compared to when the stator 11 and motor windings 12 are formed from metallic materials. It is also possible to reduce weight. Hereinafter, the area obtained by projecting the cylindrical portion 211 in the axial direction will be referred to as the motor silhouette.

[0021] A shaft hole 215 is formed in the bottom portion 213. A holding member 232 that holds the bearing 151 is provided in the shaft hole 215. The flange portions 214 are formed at two circumferential locations on opposite sides of the rotation shaft, protruding radially outward from the bottom portion 213. The number and arrangement of the flange portions 214 may vary (see FIG. 4). A metal collar 231 is insert-molded into the flange portion 214. A fixing member such as a screw (not shown) is inserted into the collar 231, and the collar 231 is fixed to a gear box that houses the reduction gear 89.

[0022] The frame member 25 is formed of a non-metallic material such as resin, and is provided so as to close the opening of the cylindrical portion 211. The front side of the frame member 25 is provided so as to protrude in a cylindrical shape, and is inserted into the radially inner side of the cylindrical portion 211.

[0023] An axial hole 251 is formed in the frame member 25, penetrating in the axial direction. A bearing 152 is fixed in the axial hole 251, and the shaft 15 is inserted through the axial hole 251. The magnet 16 is exposed on the rear side from the frame member 25 and faces the circuit board 31. A rotation angle sensor (not shown) is provided on the circuit board 31 at a position facing the magnet 16.

[0024] The configuration of the rear side of the frame member 25 is shown in Figures 3 and 4. Figure 4 shows a variation in arrangement. The frame member 25 is formed with motor wire outlet portions 252 through which the outlet wires of the motor windings 12 are inserted. The motor wire outlet portions 252 are provided radially inside a groove portion 255 (described later) on both sides of the axial hole 251. One set of the motor windings 12 is taken out from each motor wire outlet portion 252 to the ECU 30 side and connected to the circuit board 31.

[0025] A connector fixing portion 253 and a board fixing portion 254 are formed on the rear surface of the frame member 25. In the example of FIG. 2, the board fixing portion 254 is provided radially inward of the motor wire outlet portion 252, but as in the example of FIG. 4, it may be provided in an area adjacent to or concentric with the motor wire outlet portion 252. Furthermore, the connector fixing portion 253 is provided adjacent to the board fixing portion 254. In the example of FIG. 4, three connector fixing portions 253 and four board fixing portions 254 are provided, but the arrangement and number may be different. Note that the connector fixing portions 253 and the board fixing portions 254 are omitted from FIG. 3.

[0026] 2 to 4, an annular groove 255 is formed on the rear side of the frame member 25. The connection between the frame member 25 and the motor case 21, including details of the groove 255, will be described later.

[0027] 2, the ECU 30 includes a circuit board 31, a connector 41, and an ECU cover 51. The circuit board 31 is formed so that a portion of its circumference extends to the outside of the motor silhouette, and is fixed to a circuit board fixing portion 254 of the frame member 25 by a circuit board fixing member 32 such as a screw. Various electronic components that control the supply of electricity to the motor windings 12 are mounted on the circuit board 31.

[0028] The connector portion 41 has a connector body 411, a connector holder 415, an insertion convex portion 416, and a wall portion 417, and is integrally formed from resin or the like. The connector portion 41 is fixed to the connector fixing portion 253 of the frame member 25 by fixing members such as screws (not shown).

[0029] The connector body 411 protrudes from the connector holder 415 to the front outside the motor silhouette, allowing a harness (not shown) to be inserted and removed from the front. The orientation of the opening may vary, and the number of openings can be changed as desired. The connector body 411 is provided with connector terminals 412. The connector terminals 412 are electrically connected to the circuit board 31.

[0030] The connector holder 415 is formed so that a portion of its circumferential direction extends to the outside of the motor silhouette so as to fit along the circuit board 31. The insertion protrusion 416 is formed in an annular shape on the front side of the connector holder 415. The insertion protrusion 416 is inserted into the groove 255 of the frame member 25 and is liquid-tightly sealed with adhesive 291. The wall portion 417 is erected on the rear side along the outer edge of the connector holder 415. A cover insertion groove 418 is formed on the rear end face of the wall portion 417.

[0031] The ECU cover 51 has a top plate 511 and a peripheral wall 512, which are integrally formed from resin or the like. A protrusion 513 is formed at the tip of the peripheral wall 512. The protrusion 513 is inserted into the cover insertion groove 418 and is liquid-tightly sealed with adhesive 292. The circuit board 31 is housed in the housing space surrounded by the ECU cover 51 and the connector holder 415.

[0032] The connection between the motor case 21 and the frame member 25 will now be described. The motor case 21 and the frame member 25 are molded, for example, from polybutylene terephthalate (PBT) and have the same linear expansion coefficient. The motor case 21 contains carbon fiber composite material (CFRP) or glass fiber (GF) as an additive. The carbon fiber composite material or glass fiber is preferably blended at 35% or more. This improves the strength of the motor case 21.

[0033] The motor case 21 can be melted by laser irradiation. Meanwhile, the frame member 25 is formed to be laser-transparent by adjusting the additives. "Laser-transparent" can also be interpreted as meaning that the temperature rise caused by the laser irradiation for welding is suppressed to a level that does not melt the resin material. The composition of the motor case 21 and the frame member 25 can be identified by cutting out samples of each part of the completed drive device 1 and performing chemical analysis.

[0034] 5, the inner peripheral wall 257 and the outer peripheral wall 258 that constitute the groove 255 of the frame member 25 are the same height, and a flat surface is formed with a width at least sufficient to place the jig Z thereon, and the height is such that the laser irradiation to the bottom surface 256 is not hindered. By irradiating the groove 255 with a laser, the laser transmission distance to the contact surface with the motor case 21 can be shortened. The jig Z is formed in an annular shape from a laser-transmittable material such as glass, and is placed on the frame member 25 so as to cover the entire opening of the groove 255 during laser irradiation.

[0035] With the frame member 25 pressed against the motor case 21 using the jig Z, a laser beam narrower than the bottom surface 256 of the groove 255 is irradiated from the rear side. The laser beam passes through the frame member 25, causing the motor case 21 to thermally melt and weld to the frame member 25. The welded portion 219 is formed within the axial projection area of ​​the groove 255, and the motor case 21 and the frame member 25 are integrated without any boundary. The welded portion 219 is also formed on abutting surfaces that are approximately perpendicular to the axial direction in inner portions of the motor case 21 and the frame member 25 spaced from the outer peripheral walls. In FIGS. 2 and 5, the welded portion 219 is shown with a matte finish. In FIGS. 3 and 4, the welded area of ​​the welded portion 219 projected in the axial direction is shown with a matte finish.

[0036] After the motor case 21 and the frame member 25 are laser welded together, the connector portion 41, the circuit board 31, and the ECU cover 51 are assembled. The inner peripheral wall 257 and the outer peripheral wall 258 are formed to a height that allows them to hold adhesive 291 when the connector portion 41 is assembled, and the insertion protrusion 416 of the connector portion 41 is inserted into the groove 255 and sealed with the adhesive 291. That is, in this embodiment, the adhesive groove used for assembling the connector portion 41 is also used for laser irradiation.

[0037] In this embodiment, both the motor case 21 and the frame member 25 are made of non-metallic materials. This allows the drive unit 1 to be lighter in weight than when made of metallic materials. It also improves corrosion resistance. The stator 11 is molded integrally with the motor case 21. This reduces the number of parts required in the assembly process. It also suppresses vibration of the stator 11.

[0038] The motor case 21 and the frame member 25 are integrated by laser welding. This eliminates the need for a separate sealing member, reducing the number of parts. In this embodiment, laser light is irradiated onto the groove 255 from the rear side to melt the motor case 21, thereby welding the motor case 21 and the frame member 25 together. By irradiating the motor body radially outward with laser light from the rear side, the motor case 21 and the frame member 25 can be welded together without causing laser damage to the motor body. Note that while FIG. 5 illustrates the laser irradiation along the axial direction, the laser may be irradiated at an angle as long as it does not interfere with the inner circumferential wall 257 and the outer circumferential wall 258.

[0039] As described above, the drive device 1 includes the motor 10, the motor case 21, and the frame member 25. The motor 10 has the stator 11, the motor windings 12 wound around the stator 11, the rotor 13 that is rotatable relative to the stator 11 when current is applied to the motor windings 12, and the shaft 15 that rotates integrally with the rotor 13.

[0040] The motor case 21, made of a non-metallic material, has a cylindrical portion 211 and holds the stator 11. In this embodiment, the stator 11 is molded integrally with the motor case 21. A frame member 25, made of a non-metallic material, is provided on one axial side of the cylindrical portion 211. The frame member 25 abuts against an axial end face 212 of the motor case 21, and is welded at the abutting surface. By forming the motor case 21 and the frame member 25 from a non-metallic material and thermally welding the motor case 21 and the frame member 25 together by, for example, laser irradiation, corrosion resistance is improved.

[0041] The frame member 25 is made of a laser-transparent material. The motor case 21 is made of a material that can be melted by a laser. By making the frame member 25 of a laser-transparent material, the frame member 25 and the motor case 21 can be welded together by irradiating a laser from the frame member 25 side, thereby preventing the laser from affecting the inside of the motor.

[0042] The frame member 25 has an annular groove 255 that opens on the side opposite to the motor case 21. A welded portion 219 where the motor case 21 and the frame member 25 are welded is formed within a projection area of ​​the groove 255 projected in the axial direction. By irradiating the groove 255 with a laser, the distance that the laser passes through the frame member 25 can be shortened.

[0043] The end faces of the inner peripheral wall 257 and the outer peripheral wall 258 formed on both sides of the groove 255 are formed to be the same height within at least a predetermined width range. This allows laser irradiation while holding both sides of the groove 255 with the jig Z. Note that "the same height" means that an error is allowed to the extent that the jig Z can be pressed against the frame member 25 toward the motor case 21. Also, the "predetermined width range" means a width that allows the jig Z to press the frame member 25 against the motor case 21, and the height of the part that does not interfere with the jig Z may be different.

[0044] The ECU 30 includes a substrate 31 on which electronic components related to controlling the energization of the motor windings 12 are mounted, a connector portion 41 used to connect the substrate 31 to the outside, and an ECU cover 51 that houses the substrate 31, and is provided on the opposite side of the frame member 25 from the motor case 21. An insertion protrusion 416 of the connector portion 41 is inserted into at least a portion of the groove 255 and fixed with adhesive 291 as an adhesive member. In this embodiment, the insertion protrusion 416 is inserted and fixed around the entire periphery of the groove 255. By using the groove 255 used to fix the connector portion 41 also for laser irradiation, the configuration can be simplified compared to when a separate groove for laser irradiation is formed.

[0045] Second Embodiment A second embodiment is shown in Figure 6. The drive unit 2 of this embodiment differs from the above-described embodiment in the motor case 22, frame member 26, and connector portion 42, and this will be mainly described. The motor case 22 differs from the above-described embodiment in that a welded wall portion 225 is provided along the outer edge of the rear side of the cylindrical portion 211. A rear end surface 226 of the welded wall portion 225 abuts against the frame member 26.

[0046] The frame member 26 has a first cylindrical portion 261, a second cylindrical portion 262, a connector holding portion 265, etc., and is formed of a non-metallic material such as a laser-transparent resin. The first cylindrical portion 261 is inserted into the cylindrical portion 211. The second cylindrical portion 262 is formed on the rear side of the first cylindrical portion 261 and has a larger diameter than the first cylindrical portion 261, and is inserted radially inward of the welded wall portion 225. The frame member 26 abuts against the end face 226 of the motor case 22 at the radially outer side of the second cylindrical portion 262.

[0047] The connector holding portion 265 is formed so that a portion of the connector holding portion 265 in the circumferential direction extends to the outside of the motor silhouette so as to fit along the circuit board 31. A connector insertion hole 266 is formed in the connector holding portion 265. The connector portion 42 has substantially the same function as the connector main body 411, and is inserted into the connector insertion hole 266 from the rear side and fixed to the connector holding portion 265. In this embodiment, by providing the connector holding portion 265 on the frame member 26, the connector portion 42 can be made smaller.

[0048] A common groove 267, a welding groove 268, and an adhesive groove 269 are formed on the rear surface of the frame member 26. The common groove 267 is formed within a projected area of ​​the welding wall portion 225 projected in the axial direction, and along the outer edge of the frame member 26. The welding groove 268 is formed within a projected area of ​​the welding wall portion 225 projected in the axial direction, at a location spaced from the outer edge of the frame member 26. The adhesive groove 269 is formed along the outer edge of the frame member 26 outside the motor silhouette.

[0049] The common groove 267 and the adhesive groove 269 are formed continuously, and as a whole are formed in a ring shape along the outer edge of the frame member 26. The protrusion 513 of the ECU cover 51 is inserted into the common groove 267 and the adhesive groove 269, and is liquid-tightly sealed with adhesive 293.

[0050] The common groove 267 and the welding groove 268 are formed continuously and are formed as a ring along the silhouette of the motor as a whole. Specifically, the common groove 267 and the welding groove 268 are formed within the axial projection area of ​​the welding wall portion 225. The continuous common groove 267 and the welding groove 268 are formed so that they can be irradiated with laser light, similar to the groove portion 255 in the above embodiment. Furthermore, the inner and outer circumferential sides of the common groove 267 and the welding groove 268 are formed at the same height so that they can be pressed with the jig Z.

[0051] By irradiating the common groove 267 and the welding groove 268 with a laser from the rear side, the end face of the welding wall portion 225 of the motor case 22 is melted, welding the motor case 22 to the frame member 26. After the motor case 22 and the frame member 26 are laser welded together, the connector portion 42, the circuit board 31, and the ECU cover 51 are assembled. After assembly, the welding groove 268 is open to the circuit board 31 and is covered by the circuit board 31.

[0052] That is, the common groove 267 is used both for laser irradiation and for assembling the ECU cover 51. The welding groove 268 is used for laser irradiation but is not used for assembling the ECU cover 51, and the adhesive groove 269 is used for assembling the ECU cover 51 but is not used for laser irradiation.

[0053] In this embodiment, the common groove 267 and the welding groove 268 correspond to the "groove portion," and the protrusion 513 of the ECU cover 51 is inserted into the common groove 267, which is part of the groove portion, and fixed with adhesive 293. This configuration also achieves the same effects as the above embodiment.

[0054] Third Embodiment A third embodiment is shown in FIG. 7 . The drive unit 3 of this embodiment differs from the above-described embodiment in the connector unit 43 and ECU cover 52, and this difference will be mainly described. The connector unit 43 includes a connector body 431 and a connector holder 433, which are integrally formed from resin or the like. The connector body 431 is provided within the motor silhouette and allows a harness (not shown) to be inserted and removed from the rear side. The connector holder 433 has legs 434 extending axially and is fixed to the frame member 25 by through bolts 439 inserted through the legs 434. A seal groove 435 is formed on the rear surface of the connector holder 433, outside the connector body 431.

[0055] The ECU cover 52 has a top plate 521 and a peripheral wall 522, which are integrally formed from resin or the like. A protrusion 523 is formed at the tip of the peripheral wall 522. The protrusion 523 is inserted into a groove 255 formed in the rear end face of the frame member 25, and is liquid-tightly sealed with adhesive 294.

[0056] The top plate portion 521 is formed with a connector insertion hole 525 and a protrusion 526. The connector main body 431 is inserted into the connector insertion hole 525, with the opening of the connector main body 431 exposed on the rear side. The protrusion 526 is formed radially outward of the connector insertion hole 525 and protrudes toward the front side of the top plate portion 521. The protrusion 524 is inserted into a seal groove 435 of the connector portion 43 and is liquid-tightly sealed with an adhesive.

[0057] In this embodiment, the protrusion 523 of the ECU cover 52 is inserted into the groove 255, and the groove 255, which is an adhesive groove for the ECU cover 52, is also used for laser irradiation. Note that the laser welding between the motor case 21 and the frame member 25 is the same as in the first embodiment. In this way, by changing the shapes of the connector portion 43 and the ECU cover 52, the arrangement of the connector and the orientation of the opening can be changed as appropriate. This configuration also achieves the same effects as the above embodiment.

[0058] In the embodiment, the groove 255, the common groove 267 and the welding groove 268 correspond to "grooves", the ECU 30 corresponds to "control unit", the ECU covers 51 and 52 correspond to "covers", and the adhesives 291, 293 and 294 correspond to "adhesive members".

[0059] (Other Embodiments) In the above embodiment, the motor case and the frame member are made of PBT. In other embodiments, the motor case and the frame member may be made of a material other than PBT as long as they have the same linear expansion coefficient. In the above embodiment, the stator is molded integrally with the motor case. In other embodiments, the stator does not have to be molded with the motor case, and the method of fixing the stator to the motor case does not matter.

[0060] In the above embodiment, the welded portion is formed in a projection area of ​​the groove in the axial direction. In other embodiments, the motor case and the frame member may be welded by irradiating a location other than the groove with a laser, or the welded portion may be formed in a location other than the axial projection area of ​​the groove.

[0061] In the above embodiment, the drive device is applied to an electric power steering device. In other embodiments, the drive device may be applied to an in-vehicle device other than an electric power steering device, or may be applied to a device other than an in-vehicle device.

[0062] (Disclosure of Technical Ideas) This specification discloses multiple technical ideas described in the following multiple clauses. Some clauses may be described in a multiple dependent form, with the subsequent clause alternatively referring to the preceding clause. Furthermore, some clauses may be described in a multiple dependent form, with the subsequent clause referring to another multiple dependent clause. These multiple dependent clauses define multiple technical ideas.

[0063] (Technical Idea 1) A drive device comprising: a motor (10) having a stator (11), motor windings (12) wound around the stator, a rotor (13) rotatable relative to the stator when current is applied to the motor windings, and a shaft (15) rotating integrally with the rotor, a motor case (21, 22) made of a non-metallic material having a cylindrical portion (211) and holding the stator, and frame members (25, 26) made of a non-metallic material provided on one axial side of the cylindrical portion, wherein the frame members abut against end faces (212, 226) on the axial side of the motor case and are welded at the abutting surfaces. (Technical Idea 2) The drive device according to Technical Idea 1, wherein the frame members are made of a laser-transparent material, and the motor case is made of a material that can be melted by a laser. (Technical Idea 3) The frame member has an annular groove portion (255, 267, 268) that opens on the side opposite to the motor case, and a welded portion (219) at which the motor case and the frame member are welded is formed in a projected area of ​​the groove portion projected in the axial direction. (Technical Idea 4) The drive device according to Technical Idea 3, wherein end faces of an inner circumferential wall (256) and an outer circumferential wall (257) formed on both sides of the groove portion are formed to have the same height at least within a predetermined width range. (Technical Idea 5) A drive device according to Technical Idea 3 or 4, further comprising a control unit (30) provided on the opposite side of the frame member from the motor case, the control unit having a substrate (31) on which electronic components related to the control of the current supply to the motor windings are mounted, connector parts (41-43) used to connect the substrate to the outside, and a cover (51, 52) that houses the substrate therein, wherein the connector part or the cover is inserted into at least a part of the groove part and fixed with adhesive members (291, 293, 294).

[0064] As described above, the present disclosure is not limited to the above-described embodiment, and can be implemented in various forms without departing from the spirit of the present disclosure.

[0065] The present disclosure has been described based on the embodiments. However, the present disclosure is not limited to the embodiments and structures. The present disclosure also encompasses various modifications and variations within the scope of equivalents. Furthermore, various combinations and forms, as well as other combinations and forms including only one element, more than one element, or less than one element, are also within the scope and spirit of the present disclosure.

Claims

1. A drive device comprising: a motor (10) having a stator (11), motor windings (12) wound around the stator, a rotor (13) rotatable relative to the stator when current is applied to the motor windings, and a shaft (15) that rotates integrally with the rotor; a motor case (21, 22) made of a non-metallic material that has a cylindrical portion (211) and holds the stator; and frame members (25, 26) made of a non-metallic material that are provided on one axial side of the cylindrical portion, wherein the frame members abut against the axial end faces (212, 226) of the motor case, and are welded at the abutting surfaces.

2. A drive unit according to claim 1, wherein the frame member is made of a laser-transparent material, and the motor case is made of a laser-meltable material.

3. A drive unit as described in claim 1 or 2, wherein the frame member has an annular groove portion (255, 267, 268) that opens on the side opposite the motor case, and the welded portion (219) where the motor case and the frame member are welded is formed in a projection area obtained by projecting the groove portion in the axial direction.

4. A drive device according to claim 3, wherein the end faces of the inner peripheral wall (256) and the outer peripheral wall (257) formed on both sides of the groove are formed to have the same height within at least a predetermined width range.

5. A drive device as described in claim 3, further comprising a control unit (30) provided on the opposite side of the frame member from the motor case, the control unit having a substrate (31) on which electronic components related to the control of the current supply to the motor windings are mounted, connector portions (41-43) used to connect the substrate to the outside, and a cover (51, 52) that houses the substrate therein, the connector portion or the cover being inserted into at least a portion of the groove portion and fixed with adhesive members (291, 293, 294).

Images