Driving device

Abstract

To provide a driving device capable of preventing entry of water droplets and the like into a device.SOLUTION: A driving device 1 includes a motor 10 and an ECU 50. The motor 10 includes a motor housing 15 having a tubular motor case 16, a stator 12 fixed on the motor housing 15, a motor line 11 wound around the stator 12, a rotor 13 configured to rotate by electric conduction to the motor line 11, and a shaft 14 that is rotatably supported by the motor housing 15 and rotates integrally with the rotor 13. The ECU 50 includes a substrate 53 on which electronic components involved in the driving control of the motor 10 are mounted, and an ECU housing 60 that accommodates the substrate 53, and is provided on one side in an axial direction of the motor 10. An end part of the motor case 16 on the ECU 50 side is sealed by the ECU housing 60.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a drive device. [Background technology]

[0002] Conventionally, there has been known an electrically-integrated motor in which a control device is integrally formed on one side of the motor in the axial direction. For example, in Patent Document 1, a cover, a frame, and a motor case are bonded together with a sealant. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-17866 A Summary of the Invention [Problem to be solved by the invention]

[0004] For example, in a structure such as that disclosed in Patent Document 1 that uses a sealing material or packing material to prevent water droplets from entering the interior, if gaps occur due to deterioration over time or the like, there is a risk that the waterproof performance will decrease.

[0005] The present invention has been made in view of the above-mentioned problems, and has an object to provide a drive device capable of preventing the intrusion of water droplets and the like into the inside of the device. [Means for solving the problem]

[0006] A drive device (1) of the present invention includes a motor (10) and a controller (50). The motor includes a motor housing (15, 20, 30, 35) having a cylindrical motor case (16, 23, 33), a stator (12) fixed to the motor housing, a motor wire (11) wound around the stator, a rotor (13) that rotates when electricity is applied to the motor wire, and a shaft (14) that rotates integrally with the rotor.

[0007] The controller has a board (53) on which electronic components (54, 55) related to the drive control of the motor are mounted, and a controller housing (60) that houses the board, and is provided on one side in the axial direction of the motor. The controller housing seals the end of the motor case on the controller side, which makes it possible to prevent water droplets and the like from entering the inside of the device. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic configuration diagram of a steering system according to a first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view of the drive device according to the first embodiment. [Diagram 3] 2 is a schematic diagram illustrating a connection between a motor case and an ECU case according to the first embodiment. FIG. [Figure 4] 4 is a flowchart illustrating an assembly process of the drive device according to the first embodiment. [Diagram 5] FIG. 2 is an explanatory diagram illustrating assembly of a motor case and a stator according to the first embodiment. [Figure 6] FIG. 4 is an explanatory diagram for explaining assembly of the rotor ASSY according to the first embodiment. [Figure 7] FIG. 2 is an explanatory diagram for explaining assembly of the motor ASSY according to the first embodiment. [Figure 8] 3 is an explanatory diagram for explaining assembly of an ECU case and an ECU-ASSY to a motor ASSY according to the first embodiment. FIG. [Figure 9] FIG. 11 is a cross-sectional view of a drive device according to a second embodiment. [Figure 10] 10 is a flowchart illustrating an assembly process of the drive device according to the second embodiment. [Figure 11] 10A to 10C are explanatory views for explaining the formation of a motor case according to a second embodiment. [Figure 12] 13 is an explanatory diagram illustrating assembly of an ECU case to a motor ASSY according to a second embodiment. FIG. [Figure 13] FIG. 11 is a cross-sectional view of a drive device according to a third embodiment. [Figure 14] 13 is a flowchart illustrating an assembly process of the drive device according to the third embodiment. [Figure 15] 13 is an explanatory diagram illustrating assembly of an inner case according to a third embodiment. FIG. [Figure 16] 13 is an explanatory diagram illustrating the formation of a motor case according to a third embodiment and the assembly of an ECU case to the motor case. FIG. [Figure 17] FIG. 10 is a cross-sectional view of a drive device according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A driving device according to the present invention will be described below with reference to the drawings. In the following, in a number of embodiments, substantially the same components are designated by the same reference numerals, and description thereof will be omitted.

[0010] (First embodiment) The first embodiment is shown in Fig. 1 to Fig. 8. As shown in Fig. 1, a drive device 1 includes a motor 10 and an ECU 50 serving as a controller, and is applied to an electric power steering device 8. Fig. 1 shows the configuration of a steering system 90 including 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, and the like.

[0011] The steering wheel 91 is connected to a steering shaft 92. A torque sensor 94 that detects steering torque is provided on the steering shaft 92. A pinion gear 96 is provided on 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 a driver turns a steering wheel 91, a 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 according to the amount of displacement of the rack shaft 97.

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

[0014] The motor 10 is, for example, a three-phase brushless motor. The motor 10 outputs a part or all of the torque required for steering, and is driven by power supplied from a battery (not shown) to rotate the reduction gear 89 forward and reverse. The drive device 1 is a so-called "mechatronically integrated type" in which the ECU 50 is provided on one side of the motor 10 in the axial direction. The mechatronically integrated type allows the motor 10 and the ECU 50 to be efficiently arranged in a vehicle with limited mounting space. Hereinafter, when the terms "axial direction" and "radial direction" are simply used, they will mean the axial direction and radial direction of the motor 10. Also, the lower side of the paper in FIG. 2 and the like is the output end side.

[0015] As shown in Fig. 2, the motor 10 includes a stator 12, a rotor 13, a shaft 14, and a motor housing 15. The stator 12 is fixed to the motor housing 15, and a motor wire 11 is wound around the stator 12. The motor wire 11 is not shown in any figures other than Fig. 2. The rotor 13 is provided radially inside the stator 12 and is provided to be rotatable relative to the stator 12.

[0016] The shaft 14 is fitted into the rotor 13 and rotates integrally with the rotor 13. The shaft 14 is rotatably supported in the motor housing 15 by bearings 141 and 142. The end of the shaft 14 on the ECU 50 side is exposed from the motor housing 15 to the ECU 50 side, and is provided with a sensor magnet 145. The end of the shaft 14 opposite the ECU 50 is an output end, which is provided with a pulley 147 and connected to the reduction gear 89.

[0017] The motor housing 15 has a motor case 16, a front frame 17, and a rear frame 18. The motor case 16 is formed into a cylindrical shape from, for example, aluminum. The motor case 16 has a front frame 17 integrally molded on the output end side, and an ECU case 61 (described later) integrally molded on the ECU 50 side. In this specification, the state in which at least one preformed member A is inserted to form a member B is referred to as "integrally molded" or "formed as an integrally molded product," and members A and B may be made of the same material or different materials.

[0018] The front frame 17 is made of, for example, phenolic resin, and seals the end portion on the output end side of the motor case 16. The front frame 17 is formed with a bearing holding portion 171, an outer wall abutment portion 172, a flange portion 175, and the like. The bearing holding portion 171 is provided with a bearing 141.

[0019] The outer wall abutment portion 172 is formed in a cylindrical shape extending along the outer peripheral wall of the motor case 16 toward the ECU 50 side from the radially inner side. Providing the outer wall abutment portion 172 prevents water droplets and the like from entering the inside of the device from the connection portion between the motor case 16 and the front frame 17. A plurality of flange portions 175 are formed protruding radially outward, and are attached to the gear box by fixing members such as screws (not shown). They may also be attached to a housing other than the gear box.

[0020] The rear frame 18 is formed into a substantially circular plate shape from, for example, phenolic resin, and is fixed to the ECU 50 side of the motor case 16. A bearing 142 is fixed to the rear frame 18. The frames 17, 18 hold the bearings 141, 142, and can also be regarded as bearing holding members.

[0021] The ECU 50 has a board 53, a connector 57, an ECU housing 60, and the like. The board 53 is formed to extend radially outward beyond a motor area, which is an area obtained by projecting the motor case 16 in the axial direction, and is fixed to the ECU housing 60 by a fixing member 59 such as a tapping screw. A fixing member other than a tapping screw may be used, and the board 53 may be fixed to the ECU housing 60 by, for example, resin caulking. Hereinafter, the surface of the board 53 facing the motor 10 is referred to as a motor surface 531, and the surface opposite the motor 10 is referred to as a cover surface 532.

[0022] Lead wires 115 taken out from each phase of the motor wire 11 are formed to extend toward the ECU 50 and are electrically connected to the substrate 53 within the motor area. In this embodiment, the lead wires 115 are soldered to the substrate 53, but the connection method is not limited to soldering as long as an electrical connection is established, and may be, for example, an elastic connection by press-fit or a solderless connection such as a fitting connection using a socket connector.

[0023] Various electronic components such as a heating element 54, a capacitor 55, and a rotation angle sensor 56 are mounted on the substrate 53. In this embodiment, the heating element 54 and the capacitor 55 are mounted on a cover surface 532 of the substrate 53. The heating element 54 includes a switching element constituting an inverter that switches the current supply to the motor wires 11, a motor relay, a power relay, and the like. The rotation angle sensor 56 is mounted on the motor surface 531 at a position facing the sensor magnet 145, and detects the rotation of the motor 10 by detecting the rotating magnetic field of the sensor magnet 145. Note that the rotation angle sensor 56 is not shown in the description of the assembly, etc.

[0024] Connector 57 is provided on the motor surface 531 side of substrate 53 outside the motor area, and connector terminal 571 is connected to substrate 53. A flange 575 extending from the main body to the outer periphery is formed on the end of connector 57 on the substrate 53 side. Flange 575 is formed in an L-shape in cross section so that its tip projects toward the opposite side to substrate 53.

[0025] The ECU housing 60 has an ECU case 61 and an ECU cover 71, and is formed to extend radially outward from the motor area. The ECU case 61 is formed, for example, from epoxy resin into a generally cylindrical shape with a bottom that opens on the side opposite the motor 10, and is integrally molded with the motor case 16, sealing the end of the motor case 16 on the ECU 50 side.

[0026] 3, the motor case 16 is formed with a sealing hole 162 penetrating in the plate thickness direction. A plurality of sealing holes 162 are formed at locations integrally molded with the ECU case 61, spaced apart in the circumferential direction. When the motor case 16 and the ECU case 61 are integrally molded, the ECU case 61 is formed at the end of the motor case 16 on the ECU 50 side, sandwiching the radially inner and outer sides. Here, the resin of the ECU case 61 enters the sealing hole 162, thereby improving the joining strength.

[0027] Similarly, a plurality of sealing holes 163 penetrating in the plate thickness direction are formed at intervals in the circumferential direction at the portion of the motor case 16 that is integrally molded with the front frame 17. When the motor case 16 and the front frame 17 are integrally molded, the resin of the front frame 17 penetrates into the sealing holes 163, thereby improving the joining strength.

[0028] Returning to FIG. 2, the ECU case 61 is formed with an outer wall abutment portion 611, a through hole 612, a board holding portion 613, a connector attachment portion 614, and a connector insertion hole 615 (see FIG. 8), etc.

[0029] The outer wall abutment portion 611 is formed in a cylindrical shape extending along the outer peripheral wall of the motor case 16 toward the output end side from the radially inner side. Providing the outer wall abutment portion 611 suppresses the intrusion of water droplets and the like into the inside of the device from the connection portion between the motor case 16 and the ECU case 61. Note that the outer wall abutment portion 611 may not be provided, and the axial length of the radially outer portion of the motor case 16 at the connection portion between the motor case 16 and the ECU case 61 may be equal to or less than the axial length of the radially inner portion. The same applies to the outer wall abutment portion 172 of the front frame 17. Also, the outer wall abutment portion 611 is omitted from illustrations other than FIG. 2.

[0030] The through hole 612 is provided so as to penetrate in the axial direction at a position corresponding to the shaft 14, and the sensor magnet 145 is disposed inside. The board holding portion 613 is formed in the motor area, and the board 53 is fixed thereto by a fixing member 59. The connector 57 is attached to the connector attachment portion 614 by adhesive or the like. In detail, the main body portion of the connector 57 is inserted into the connector insertion hole 615 with the opening exposed to the outside, and then the flange portion 575 is inserted into the connector attachment portion 614 to which adhesive or the like is applied, thereby attaching the connector 57 to the ECU case 61.

[0031] The ECU cover 71 is made of, for example, epoxy resin, and is provided on the cover surface 532 side of the substrate 53. The ECU cover 71 is molded integrally with the ECU case 61, and resin-seals the substrate 53, and the heat generating element 54 and the capacitor 55 mounted on the cover surface 532 side of the substrate 53. The ECU cover 71 is formed with heat dissipation fins 711 in an element mounting area, which is an area obtained by projecting the area where the heat generating element 54 is mounted in the axial direction.

[0032] The assembly process of the drive device 1 of this embodiment will be described with reference to the flow chart of Fig. 4 and Fig. 5 to Fig. 8. Hereinafter, the "step" such as step S10 will be omitted, and the steps will simply be referred to as "S".

[0033] As shown in Fig. 5, in S10, the front frame 17 is integrally molded with the motor case 16. In S11, the stator 12 is shrink-fitted to the motor case 16. As shown in Fig. 6, in S12, the bearing 142 is fixed to the rear frame 18 by crimping, press-fitting, or the like. In S13, the bearings 141, 142 are press-fitted into the rotor assembly in which the shaft 14 is press-fitted into the rotor 13. Note that the order of S10, S11 and S12, S13 may be reversed, or they may be performed in parallel.

[0034] As shown in Fig. 7, in S14, the rotor ASSY in the state shown on the right side of Fig. 6 is assembled to the motor case 16 in the state shown on the right side of Fig. 5. Specifically, the rear frame 18 is shrink-fitted to the motor case 16. The bearing 141 is inserted into the bearing holder 171 of the front frame 17. In S15, the pulley 147 is press-fitted into the end of the shaft 14 on the output end side, and the sensor magnet 145 is press-fitted into the end of the shaft 14 on the ECU 50 side. Hereinafter, the state in which the stator 12, the front frame 17, the rear frame 18, etc. are assembled to the motor case 16 is referred to as the motor ASSY.

[0035] 8, in S16, in the state of the motor assembly, the ECU case 61 is molded integrally with the motor case 16 by resin (see the left side of FIG. 8). In S17, adhesive is applied to the connector attachment portion 614 of the ECU case 61. In S18, the ECU-ASSY with the connector 57 attached is attached to the ECU case 61 (see the right side of FIG. 8).

[0036] In S19, the lead wires 115 are electrically connected to the substrate 53. If the connection between the lead wires 115 and the substrate 53 is a solderless connection such as a press-fit connection, the connection is completed when the ECU-ASSY is attached to the ECU case 61 in S18, and S19 is omitted. In S20, the ECU-ASSY is sealed with resin, and the ECU cover 71 is formed (see FIG. 2). In the drawings, the rotor ASSY is designated as "RA", the motor ASSY as "MA", and the ECU ASSY as "EA" as appropriate.

[0037] For example, as a comparative example, if the rear frame were a metal heat sink and the heat from the heating element 54 was to be dissipated to the motor case 16 side, the heating element 54 had to be mounted on the motor surface 531 side of the substrate 53 and within the motor area.

[0038] In contrast, in the drive unit 1 of this embodiment, the heat generating element 54 is embedded in resin in the ECU cover 71, and heat is dissipated by air radiation through the ECU cover 71 with which the heat generating element 54 is in direct contact. This makes it possible to mount the heat generating element 54 on the cover surface 532 side or outside the motor area, improving the freedom of board design. Also, there is no need for an intermediate material such as heat dissipation gel that is required when dissipating heat to a metal heat sink.

[0039] The ECU case 61 is molded integrally with the motor case 16 by insert molding, and seals the end of the motor case 16. The front frame 17 is molded integrally with the motor case 16 by insert molding, and seals the end of the motor case 16. This makes it possible to prevent water droplets, dust, etc. from entering the inside of the device with a simple configuration without any gap corrosion. In addition, since the ECU case 61 and the front frame 17 are sealed without using a sealant such as an adhesive to connect the motor case 16, no gaps are created due to deterioration of the sealant over time, and waterproof performance can be maintained over time. It is preferable that the ECU case 61 and the front frame 17, which are molded integrally, and the motor case 16 are made of materials with similar linear expansion coefficients.

[0040] In this embodiment, the motor case 16 is made of metal, and the front frame 17 is made of resin. In other words, in this embodiment, instead of forming the motor case as a cylindrical shape with a bottom and the cylindrical part and the side opposite to the ECU 50 as one member, the cylindrical motor case 16 and the approximately disk-shaped front frame 17 are separated, and the end of the metal motor case 16 is molded with resin to form the front frame 17, so that the motor case 16 and the front frame 17 are molded as one piece. This allows the members to be separated without deteriorating corrosion resistance. Note that since the front frame 17 is relatively easy to form by making it a separate member from the motor case 16, it is also possible to use a material that has good corrosion resistance and relatively low fluidity.

[0041] As described above, the drive device 1 includes the motor 10 and the ECU 50. The motor 10 includes a motor housing 15 having a cylindrical motor case 16, a stator 12 fixed to the motor housing 15, a motor wire 11 wound around the stator 12, a rotor 13 that rotates when electricity is applied to the motor wire 11, and a shaft 14 that is rotatably supported by the motor housing 15 and rotates integrally with the rotor 13.

[0042] The ECU 50 has a board 53 on which electronic components related to drive control of the motor 10 are mounted, and an ECU housing 60 that houses the board 53, and is provided on one axial side of the motor 10. The electronic components include a heat generating element 54 and a capacitor 55. The ECU housing 60 seals the end of the motor case 16 on the ECU 50 side. In detail, the motor case 16 and the ECU case 61 are formed as an integrally molded product, and the end of the motor case 16 on the ECU 50 side is directly sealed by the ECU case 61.

[0043] This makes it possible to eliminate any gap between the motor case 16 and the ECU housing 60, thereby making it possible to prevent water droplets, foreign matter, etc. from entering the inside of the device through the connection point between the motor 10 and the ECU 50.

[0044] The motor housing 15 has a front frame 17 that seals the end of the motor case 16 opposite to the ECU 50. This allows the front frame 17 to be formed without deteriorating corrosion resistance.

[0045] The ECU housing 60 sandwiches the radially inner and outer sides of the end of the motor case 16 on the ECU 50 side. The front frame 17 also sandwiches the radially inner and outer sides of the end of the motor case 16 opposite the ECU 50. By sandwiching the motor case 16 from both radial sides with the resin ECU case 61 or the front frame 17, the reliability of the connection can be improved.

[0046] At the connection points between the ECU housing 60 and the motor case 16, the radially outer portion of the ECU housing 60 has a longer axial length than the radially inner portion of the ECU housing 60. ... By providing the outer wall abutment portions 172, 611 and forming the axial length relatively longer on the radially outer side, it is possible to further prevent water droplets and the like from entering the inside of the device.

[0047] Second embodiment The second embodiment is shown in Figures 9 to 12. The second to fourth embodiments differ mainly in the motor housing, so description of the ECU 50 etc. will be omitted and the description will focus on the configuration related to the motor housing.

[0048] 9, the motor housing 20 of this embodiment has a front frame 21, a rear frame 22, and a motor case 23. The front frame 21 has a bearing holding portion 211, a stator abutment portion 212, and a plurality of flange portions 215, and is formed of a metal such as an aluminum alloy.

[0049] The bearing holding portion 221 holds the bearing 141. The stator abutment portion 212 is formed in a cylindrical shape along the inner peripheral wall of the motor case 23. The flange portion 215 is formed to protrude radially outward, and is provided so as to be attachable to a housing by a fixing member such as a screw (not shown).

[0050] The rear frame 22 has a bearing holding portion 221 and a stator abutment portion 222, is made of a metal such as an aluminum alloy, and is provided on the ECU 50 side of the stator 12. The bearing 142 is fixed to the bearing holding portion 221 by press fitting or the like. The stator abutment portion 222 is formed in a cylindrical shape along the inner circumferential wall of the motor case 23.

[0051] The motor case 23 is formed in a generally cylindrical shape from, for example, phenolic resin. The motor case 23 is integrally formed with the side surfaces of the stator 12, the front frame 21, and the rear frame 22. A sealing hole 231 penetrating in the plate thickness direction is formed at a location of the motor case 23 where the motor case 23 is connected to the ECU case 61. The resin of the ECU case 61 fills the sealing hole 231, improving the reliability of the connection.

[0052] The assembly process of the motor assembly of this embodiment will be described with reference to the flowchart of Fig. 10, Fig. 11 and Fig. 12. The steps S30 and S31 are similar to the steps S12 and S13 in Fig. 4, although the material and shape of the rear frame 22 are different from those of the first embodiment.

[0053] 11, in S32, the front frame 21, the stator 12, and the rotor ASSY are stacked. At this time, on the radially outer side, the front frame 21, the stator 12, and the rear frame 22 are stacked in this order from the output end side, and the stator abutment portion 212 of the front frame 21 and the stator abutment portion 222 of the rear frame 22 abut against the stator 12. This determines the axial position.

[0054] In S33, the radial outside of the front frame 21, the stator 12, and the rear frame 22 are sealed with resin to form the motor case 23. The processing from S15 onwards is the same as in the first embodiment, and as shown in Fig. 12, a pulley 147 is press-fitted into the end of the shaft 14 on the output end side, and a sensor magnet 145 is press-fitted into the end of the shaft 14 on the ECU 50 side. Then, the ECU case 61 is resin-molded integrally with the motor case 23. The assembly of the ECU 50 is the same as in the above embodiment, and therefore a description thereof will be omitted.

[0055] In this embodiment, the stator 12, the front frame 21, and the rear frame 22 are integrally resin-sealed in the motor case 23. This increases the fixing force between the components. Also, the thickness required to ensure the fixing strength can be reduced, which contributes to reducing the weight of the drive unit 1. Also, by molding the sides of the stator 12 and the frames 21 and 22 together and forming the motor case 23 by integral molding, it is possible to prevent water droplets and the like from entering the inside of the device without using a sealant or the like.

[0056] In this embodiment, the motor case 23 is made of resin. In detail, the motor housing 20 has a front frame 21 provided on one axial side of the stator 12, and a rear frame 22 provided on the other axial side of the stator 12. The motor case 23 is formed on the radially outer side of the front frame 21, the stator 12, and the rear frame 22 stacked in the axial direction. This allows the front frame 21, the stator 12, and the rear frame 22 to be more firmly connected to the motor case 23, thereby improving the reliability of the connection of the members. In addition, the same effects as those of the above embodiment are achieved.

[0057] Third embodiment The third embodiment is shown in Figures 13 to 16. A motor housing 30 of this embodiment has a front inner case 31, a rear inner case 32, and a motor case 33.

[0058] The front inner case 31 has a bearing holding portion 311 and a stator holding portion 312, and is formed of, for example, an aluminum alloy or the like in a generally cylindrical shape with a bottom that opens to the ECU 50 side. The bearing holding portion 311 holds the bearing 141. The stator holding portion 312 is formed in a cylindrical shape, and an end portion on the ECU 50 side is provided between the stator 12 and the motor case 33.

[0059] The rear inner case 32 has a bearing holding portion 321 and a stator holding portion 322, and is formed of, for example, an aluminum alloy or the like in a generally cylindrical shape with a bottom that opens on the side opposite the ECU 50. A bearing 142 is fixed to the bearing holding portion 321. The stator holding portion 322 is formed in a cylindrical shape. An end of the stator holding portion 322 opposite the ECU 50 is provided between the stator 12 and the motor case 33, and abuts against the front inner case 31 at its tip surface.

[0060] The motor case 33 is formed in a generally cylindrical shape from, for example, phenolic resin. The motor case 33 is formed by integrally molding the side surfaces of the inner cases 31, 32. A sealing hole 331 penetrating in the plate thickness direction is formed at a portion of the motor case 33 where the motor case 33 is connected to the ECU case 61. The resin of the ECU case 61 fills the sealing hole 331, thereby improving the reliability of the connection. The motor case 33 is formed with a plurality of flanges 335 protruding radially outward for attachment to a housing by fixing members such as screws (not shown).

[0061] The assembly process of the motor ASSY of this embodiment will be described with reference to the flowchart of Fig. 14 and Figs. 15 and 16. As shown in the lower left of Fig. 15, in S40, the stator 12 is shrink-fitted into the front inner case 31 so that the bearing holder 311 is on the opposite side to the side from which the lead wires 115 of the stator 12 are taken out. The front inner case 31 and the stator 12 may be fixed by a method other than shrink-fitting. The same applies to the fixing of the rear inner case 32 and the stator 12.

[0062] As shown in the upper part of Fig. 15, in S41, bearing 142 is press-fitted into rear inner case 32, and in S42, bearings 141, 142 are press-fitted into the rotor ASSY. As shown in the lower right part of Fig. 15, in S43, rear inner case 32 is placed over stator 12 and shrink-fitted so that the opening side faces front inner case 31. The abutment positions of inner cases 31, 32 need only be such that stator 12 can be shrink-fitted to both, and may be offset from the center position in the axial direction of stator 12.

[0063] In S44, as shown in Fig. 16, the front inner case 31 and the rear inner case 32 are molded integrally with resin to form the motor case 33. The processing from S15 onwards is the same as in the first embodiment, and a pulley 147 is press-fitted into the end of the shaft 14 on the output end side, and a sensor magnet 145 is press-fitted into the end of the shaft 14 on the ECU 50 side. Then, the ECU case 61 is molded integrally with the motor case 33 with resin. As the assembly on the ECU side is the same as in the above embodiment, a description thereof will be omitted.

[0064] In this embodiment, the stator 12 is fixed to the inner cases 31 and 32, and the outside is sealed with resin, thereby preventing the intrusion of water droplets and the like into the inside of the device without using a sealing material, etc. Also, the reliability of corrosion resistance can be improved.

[0065] In this embodiment, the motor housing 30 has a front-side inner case 31 fixed to the radial outside of the stator 12 and formed extending to one side in the axial direction of the stator 12, and a rear-side inner case 32 fixed to the radial outside of the stator 12 and formed extending to the other side in the axial direction of the stator 12. The motor case 33 is formed radially outside the front-side inner case 31 and the rear-side inner case 32. This makes it possible to form the motor case 33 relatively easily. In addition, the same effects as those of the above embodiment are achieved.

[0066] (Fourth embodiment) The fourth embodiment is shown in Fig. 17. A motor housing 35 of this embodiment has a front inner case 36, a front frame 37, a rear inner case 32, and a motor case 33. In this embodiment, a front frame 37 having a bearing holding portion 371 that holds a bearing 141 is formed separately from the front inner case 36. In the assembly process, before shrink-fitting the stator 12 into the front inner case 36, the front frame 37 is fixed to the front inner case 36 by shrink-fitting, press-fitting, or the like. The subsequent assembly process is the same as that of the third embodiment.

[0067] In this embodiment, by making the front frame 37 separate from the front inner case 36, the front inner case 36 can be formed by press working, which can improve productivity. In addition, the same effects as those of the above embodiment can be achieved.

[0068] In the embodiment, the front frame 17 corresponds to the "frame", the front frame 21 corresponds to the "first frame", the rear frame 22 corresponds to the "second frame", the front side inner case 31 corresponds to the "first inner case", the rear side inner case 32 corresponds to the "second inner case", the ECU 50 corresponds to the "controller", and the ECU housing 60 corresponds to the "controller housing".

[0069] (Other embodiments) In the above embodiment, an example has been shown in which phenol resin is mainly used as the material for the front frame and rear frame, and epoxy resin is used as the material for the controller housing. In other embodiments, the controller housing may be made of a material other than epoxy resin. Also, the motor housing may be made of a material other than phenol resin, for example, the rear frame may be made of a metal with good thermal conductivity such as an aluminum alloy to further improve heat dissipation. Also, in the first embodiment, the motor case may be made of resin. That is, it may be "the drive device according to any one of aspects 1 to 6, in which the motor case is made of resin."

[0070] In the above embodiment, the motor case is formed by integrally molding the front frame and the motor case as separate members. In another embodiment, the motor case may be formed into a cylindrical shape with a bottom that opens to the ECU side, and the motor case and the front frame may be formed into a single member. As a supplementary note, even when the motor case is formed into a cylindrical shape with a bottom, it is still included in the concept of a "cylindrical motor case."

[0071] In the above embodiment, when the motor case and the controller housing are integrally molded, a sealing hole is formed in the motor case, and the motor case is integrally molded with the controller housing sandwiching the radially inner and outer sides. In other embodiments, when the motor case and the ECU housing are integrally molded, the motor case does not have to be sandwiched between the radially inner and outer sides. Also, the sealing hole may be omitted. The same applies to the connection points between the motor case and the front frame.

[0072] In the above embodiment, the heat dissipation rib is provided in the axial projection area of ​​the heat generating component. In other embodiments, depending on the thermal mass of the controller housing, the heat dissipation rib may be omitted, or a separate structure for heat dissipation (for example, a metal plate with good thermal conductivity or a flow passage portion through which a cooling fluid can flow) may be provided.

[0073] In the above embodiment, the connector is provided on the motor surface side of the board, with the opening facing the output end side in the axial direction. In other embodiments, the connector may be provided on the cover surface of the board, or the opening may face in a different direction. Also, multiple connectors may be provided. Also, the element arrangement on the board may be different from that of the above embodiment. Furthermore, as long as heat dissipation from the electronic components can be ensured, the electronic components do not need to be embedded in the controller housing.

[0074] In the above embodiment, the controller is formed to extend radially outward beyond the motor region. In other embodiments, the controller may be provided within the motor region. 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.

[0075] As described above, the present invention is not limited to the above-described embodiment, and can be embodied in various forms without departing from the spirit of the invention. [Explanation of symbols]

[0076] 1 Drive unit 10 Motor 11 Motor wire 12 stator 13 rotor 14 shaft 15, 20, 30...Motor housing 16, 23, 33 Motor case 50···ECU (controller) 53... Substrate 54 Heat generating element (electronic component) 55 Capacitor (electronic component) 60···ECU housing (controller housing)

Claims

1. a motor (10) having a motor housing (15, 20, 30, 35) with a cylindrical motor case (16, 23, 33), a stator (12) fixed to the motor housing, a motor wire (11) wound around the stator, a rotor (13) that rotates when current is applied to the motor wire, and a shaft (14) that rotates integrally with the rotor; a controller (50) provided on one side of the motor in the axial direction, the controller having a board (53) on which electronic components (54, 55) related to drive control of the motor are mounted and a controller housing (60) that houses the board; Equipped with The controller housing is made of resin, and the end of the motor case on the controller side is molded into a single piece by resin molding and sealed.

2. a motor (10) having a motor housing (15, 20, 30, 35) with a cylindrical motor case (16, 23, 33), a stator (12) fixed to the motor housing, a motor wire (11) wound around the stator, a rotor (13) that rotates when current is applied to the motor wire, and a shaft (14) that rotates integrally with the rotor; a controller (50) provided on one side of the motor in the axial direction, the controller having a board (53) on which electronic components (54, 55) related to drive control of the motor are mounted and a controller housing (60) that houses the board; Equipped with The controller housing is a drive device that sandwiches and seals the radially inner and outer sides of the controller side end of the motor case around the entire circumference.

3. 3. The drive device according to claim 2, wherein, at a connection point between the controller housing and the motor case, a portion of the controller housing that runs along an outer wall of the motor case has a longer axial length than a portion that is radially inward of the motor case.

4. The drive device according to any one of claims 1 to 3, wherein the motor housing has a frame (17) sealing an end of the motor case opposite to the controller.

5. The drive device according to claim 4 , wherein the frame sandwiches the radially inner and outer sides of the end of the motor case opposite to the controller.

6. 6. The drive device according to claim 5, wherein at a connection point between the frame and the motor case, the axial length of a portion of the frame that runs along an outer wall of the motor case is longer than the axial length of a portion that is radially inward of the motor case.

7. The motor case is made of resin, The motor housing (20) has a first frame (21) provided on one side of the stator in the axial direction and a second frame (22) provided on the other side of the stator in the axial direction, The drive device according to any one of claims 1 to 3, wherein the motor case (23) is formed radially outward when the first frame, the stator, and the second frame are stacked together.

8. a motor (10) having a motor housing (30, 35) with a cylindrical motor case (33), a stator (12) fixed to the motor housing, a motor wire (11) wound around the stator, a rotor (13) that rotates when current is applied to the motor wire, and a shaft (14) that rotates integrally with the rotor; a controller (50) provided on one side of the motor in the axial direction, the controller having a board (53) on which electronic components (54, 55) related to drive control of the motor are mounted and a controller housing (60) that houses the board; Equipped with the controller housing seals the end of the motor case on the controller side; The motor case is made of resin, The motor housing has a first inner case (31, 36) fixed to the radial outside of the stator and extending to one side in the axial direction of the stator, and a second inner case (32) fixed to the radial outside of the stator and extending to the other side in the axial direction of the stator, The motor case (33) is a drive device formed radially outside the first inner case and the second inner case.

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