Drive unit

Abstract

To provide a driving unit that prevents the generation of an excessive stress at a connection of a connector terminal and an end substrate.SOLUTION: A connector housing 50 has a bottomed cylindrical shape having a top plate part 561 and an outer cylinder part 562 extending from an outer edge of the top plate part 561. The connector housing 50 has one or more connectors 57, 58 each having a frontage directed to the opposite side of an end substrate 33. Two or more connector terminals 45 are provided for one connector, and the plurality of connector terminals are connected to the end substrate 33 at one end, and inserted through terminal insertion holes 54 formed in the bottom of the frontages of the connectors 57, 58 and exposed to the frontages of the connectors at the other end. A connector terminal binder 65 holds an intermediate part of the plurality of connector terminals 45 to bind a group of connector terminals 45 corresponding to the connectors. The connector terminals 45 are inserted into the terminal insertion holes 54 to prevent a situation in which the connector terminals are brought into contact with inner walls of the terminal insertion holes 54 and deformed following the connector housing 50.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] 2. Description of the Related Art Conventionally, a drive device in which a motor and a control unit are integrated together is known.

[0003] For example, in the integrated electric power steering device disclosed in Patent Document 1, the control unit is configured as a module including a wiring board on which an inverter circuit and a CPU are mounted, a housing for accommodating the wiring board, and a connector provided in the housing. Connector terminals for power supply line terminals and signal line terminals are connected between the connector and the wiring board. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2017 / 068636 Summary of the Invention [Problem to be solved by the invention]

[0005] Hereinafter, in this specification, the resin housing with the connector integrally provided is referred to as the "connector housing". In the device of Patent Document 1, the part of the crank-shaped connector terminal that extends in a direction perpendicular to the motor shaft is embedded in the top plate of the connector housing, and the tip of the terminal protrudes from the inner wall surface of the connector housing toward the wiring board. In other words, it is recognized that the connector terminal is insert-molded into the connector housing.

[0006] This connector housing is a large resin part with a diameter equivalent to the outer diameter of the motor, and has a bottomed cylindrical shape with an outer tube extending axially from the outer edge of the top plate, so that the central region of the top plate is prone to warping and deformation when the temperature changes. If the connector terminals are firmly fixed to the connector housing by insert or outsert molding, the connector terminals will displace in response to the relative displacement of the connector housing caused by the difference in the linear expansion coefficient of each component when the temperature changes. This causes excessive stress to be applied to the connection between the connector terminals and the board and to the electronic components around the connection, which may cause the connection to break or the electronic components to fail.

[0007] In addition, in a drive device in which two or more boards are arranged in layers within a control unit, the axial length of the outer cylinder of the connector housing is long and the size is large, so that the displacement during temperature changes becomes more significant. In this specification, the board closest to the connector among the two or more boards is referred to as the "end board." In a drive device equipped with two or more boards, it is more important to prevent the generation of excessive stress at the connection between the connector terminal and the board during temperature changes.

[0008] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide a drive device that prevents the occurrence of excessive stress at the connection portion between the connector terminal and the end board. [Means for solving the problem]

[0009] The drive device according to the present invention is configured integrally with a motor (80) including a stator (860) and a rotor (865), and a control unit (10) that is provided on one axial side of the motor and drives and controls the motor. The drive device includes a metal motor frame (840), one or more circuit boards, a resin connector housing (50), a plurality of connector terminals (45), and one or more resin connector terminal binders (65).

[0010] The motor frame is provided at the end of the motor on the control unit side in the axial direction. One or more boards are provided on the opposite side of the motor frame from the motor, including an end board (33) provided on the side farthest from the motor frame. The one or more boards are mounted with electronic components that constitute the control unit.

[0011] The connector housing is a cylindrical member with a bottom, and has a top plate portion (561) facing the end board, and an outer tube portion (562) extending from the outer edge of the top plate portion toward the motor and having an end fixed to the motor or the motor frame. The connector housing has one or more connectors (57, 58) on the top plate portion, with their openings facing away from the end board.

[0012] Two or more connector terminals are provided for each connector, one end of which is connected to the end board and the other end of which is inserted through a terminal insertion hole (54) formed in the bottom of the opening of the connector and exposed at the opening of the connector.

[0013] The connector terminal binder holds intermediate portions of a plurality of connector terminals so as to bundle a group of connector terminals corresponding to each connector, or to bundle a plurality of groups of connector terminals corresponding to adjacent connectors. The connector terminal binder has one or more convex stoppers (656) formed on the end board side to regulate the distance between the end board and the connector terminal binder. The connector terminals have flanges (46) that come into contact with the surface of the connector terminal binder on the end board side, and are positioned in the axial direction of the motor.

[0014] Each connector terminal is inserted into the terminal insertion hole so as to be prevented from being displaced following the connector housing due to contact with the inner wall of the terminal insertion hole. For example, each connector terminal may be fitted with a clearance between the connector terminal and the inner wall of the terminal insertion hole. Alternatively, the connector terminal may be configured to slide along the inner wall of the terminal insertion hole.

[0015] Furthermore, by bundling the multiple connector terminals with a connector terminal binder, the relative positional accuracy of each connector terminal is ensured. Therefore, the stress generated between each connector terminal and the inner wall of the terminal insertion hole is prevented from being transmitted to the connection portion with the end substrate. Therefore, the drive device of the present invention can prevent the generation of excessive stress at the connection portion between the connector terminal and the end substrate when the temperature changes. Therefore, it is possible to prevent breakage of the connection portion and failure of electronic components around the connection portion. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic configuration diagram of an electric power steering device to which a drive device is applied; [Diagram 2] FIG. 4 is a partial cross-sectional view showing a motor unit of the drive device. [Diagram 3] FIG. 3 is a view taken in the direction of arrow III in FIG. 2 . [Figure 4] FIG. 2 is a schematic cross-sectional view of a control unit according to the first embodiment. [Diagram 5] 1A and 1B are enlarged cross-sectional views showing examples of connection configurations between a terminal and a board by (a) soldering and (b) press-fit connection. [Figure 6] 1A is a plan view of a connector terminal binder according to a first embodiment, and FIG. [Figure 7] FIG. 3 is a schematic cross-sectional view of a control unit according to the first embodiment before assembly. [Figure 8] FIG. 4 is a schematic cross-sectional view of a control unit according to the first embodiment during assembly. [Figure 9] 11A and 11B are diagrams illustrating the relationship between a connector terminal and a terminal insertion hole in a comparative example. [Figure 10] 4A and 4B are diagrams illustrating the relationship between connector terminals and terminal insertion holes in one aspect and another aspect of the embodiment; [Figure 11] FIG. 11 is a schematic cross-sectional view of a control unit according to a second embodiment. [Figure 12] FIG. 11 is a schematic cross-sectional view of a control unit according to a third embodiment. [Figure 13] FIG. 13 is a schematic cross-sectional view of a control unit according to a reference embodiment during assembly. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, multiple embodiments of the drive device according to the present invention will be described with reference to the drawings. In multiple embodiments, substantially the same configurations are given the same reference numerals and the description will be omitted. The first to third embodiments are collectively referred to as "the present embodiment." The drive device of the present embodiment is applied, for example, as a steering assist motor of an electric power steering device, and the motor and a control unit that drives and controls the motor are integrally configured.

[0018] [Electric power steering device configuration] A schematic configuration of an electric power steering device 99 will be described with reference to Fig. 1. Although a rack-assist type electric power steering device is illustrated in Fig. 1, a drive unit 800 of this embodiment is similarly applicable to a column-assist type electric power steering device. A steering system 90 including the electric power steering device 99 includes a steering wheel 91, a steering shaft 92, a pinion gear 96, a rack shaft 97, wheels 98, the electric power steering device 99, and the like.

[0019] A torque sensor 93 that detects steering torque is provided on a steering shaft 92 to which a steering wheel 91 is connected. A pinion gear 96 that meshes with a rack shaft 97 is provided at the end of the steering shaft 92. When the driver turns the steering wheel 91, the rotational motion of the steering shaft 92 is converted into linear motion of the rack shaft 97 by the pinion gear 96. A pair of wheels 98 connected to both ends of the rack shaft 97 are steered to an angle that corresponds to the amount of displacement of the rack shaft 97.

[0020] The electric power steering device 99 includes a drive device 800 in which a motor 80 and a control unit 10 are integrated, and a reduction gear 89 that reduces the speed of rotation of the motor 80 and transmits it to a rack shaft 97. The motor 80 is a two-system three-phase brushless motor having two sets of three-phase windings. The control unit 10 has at least a "two drive systems" configuration capable of supplying power to the two sets of three-phase windings by two inverter circuits. The motor 80 outputs steering assist torque by being supplied with three-phase AC power converted from DC power by the inverter circuit of the control unit 10.

[0021] The vehicle system connector 57 of the control unit 10 is supplied with DC power from a vehicle power supply 905, and also inputs and outputs communication signals to and from a vehicle communication network ("CAN" in the figure) 906. A sensor signal detected by a torque sensor 93 is input to the signal system connector 58 via a harness 94. In this way, the vehicle system connector 57 and the signal system connector 58 are configured as connectors with different openings.

[0022] [Drive system configuration] The overall configuration of the drive device 800 will be described with reference to Figures 2 and 3. The direction parallel to the rotation axis O of the motor 80 shown in Figure 2 is referred to as the "axial direction", and the view from the upper side of Figure 2 in the axial direction is referred to as the plan view. The control unit 10 is provided on one side of the motor 80 in the axial direction. In other words, the drive device 800 has a so-called "mechanically and electrically integrated" configuration.

[0023] The motor 80 has a motor case 830, a motor frame 840, a stator 860, a rotor 865, etc. The motor case 830 is formed in a generally bottomed cylindrical shape consisting of a bottom portion 831 and a cylindrical portion 832, and the control unit 10 is provided on the opening side. A groove forming wall 834 having a thin plate thickness is formed on the opening side end of the cylindrical portion 832 via a stepped portion 833.

[0024] The stator 860 is fixed to the inside of the cylinder portion 832 of the motor case 830, and a three-phase motor winding 880 is wound around the stator 860. A rotating magnetic field is formed in the stator 860 by controlling the supply of electricity to the motor winding 880 by the control unit 10. The rotor 865 is a stator 860 A shaft 870 is fixed to the center of the shaft 870. The shaft 870 is rotatably supported by a front bearing 871 held by a bottom 831 of the motor case 830, and a rear bearing 872 held by the motor frame 840.

[0025] Rotor 865 has a plurality of permanent magnets 867 provided on the outer periphery of rotor core 866. Rotor 865 rotates about shaft 870 due to a rotating magnetic field formed in stator 860. A sensor magnet 875 for detecting the rotation angle is provided on the end of shaft 870 on the control unit 10 side.

[0026] Motor frame 840 is made of aluminum alloy or the like, and has frame portion 841, flange portion 842, heat sink 845, etc. Frame portion 841 is press-fitted into the inside of motor case 830. Flange portion 842 formed on the outer periphery of frame portion 841 abuts against step portion 833 of motor case 830. A seal groove 843 filled with adhesive is formed in an annular space defined by the outer wall of frame portion 841, the surface of flange portion 842 facing control unit 10, and the inner wall of groove forming wall 834 of motor case 830.

[0027] The connector housing 50 is formed of a resin material such as PBT, and has a bottomed cylindrical shape having a top plate portion 561 and an outer cylinder portion 562. A convex portion 563 protruding in the axial direction is formed in an annular shape at the tip of the outer cylinder portion 562. The convex portion 563 is inserted into a seal groove 843, and the outer cylinder portion 562 is fixed to the motor 80 or the motor frame 840. The top plate portion 561 is provided with connectors 57 and 58 whose openings face the opposite side to the motor 80. The connector housing 50 is a large resin part having a diameter equivalent to the outer diameter of the motor 80, and has a U-shaped cross section, so that warping and deformation are likely to occur in the central region of the top plate portion 561 when the temperature changes.

[0028] Fig. 3 shows an example of the arrangement of the connectors 57, 58. Note that Fig. 3 is a view seen in the direction of the arrow III in Fig. 2, but is not drawn to the same scale as Fig. 2 but is drawn to the same scale as Figs. 6(a) and (b), which are plan views of the components inside the control unit 10.

[0029] The vehicle system connector 57 and the signal system connector 58 may be provided in a pair as shown in Fig. 3, or in other arrangements, two pairs may be provided for redundancy. The configuration in which two pairs of connectors 57, 58 are provided is mainly adopted in a "completely dual system" drive device in which two systems of inverter circuits are connected to separate power sources and various signals are input and output redundantly. On the other hand, in a "dual drive system" drive device in which two systems of inverter circuits are connected in parallel to a common power source and various signals are shared between the systems, mainly one pair of connectors 57, 58 is provided.

[0030] The vehicle connector 57 is provided with two power terminals 45p including a positive power terminal connected to the positive pole of the vehicle power supply 905 and a ground terminal connected to the ground, and seven communication terminals 45c, for example, connected to a vehicle communication network 906 such as CAN. The power terminal 45p, through which a large current flows, has a connection portion with the harness formed in a rectangular column shape, and the board side is divided into three cylindrical shapes, for example. The signal connector 58 is provided with eight sensor terminals 45s, for example, connected to the harness 94 from the torque sensor 93. The symbols "45p", "45c", and "45c" indicating the type of connector terminal 45 are used only in FIG. 3. In FIG. 4 and subsequent figures, the terminals are uniformly referred to as "connector terminals 45" without distinguishing between their uses.

[0031] The connector housing 50 accommodates one or more boards on which electronic components constituting the control unit 10 are mounted. The one or more boards are provided on the opposite side of the motor frame 840 from the motor 80 (upper side in FIG. 2). The one or more boards also include an "end board" provided on the side furthest from the motor frame 840.

[0032] Next, the configuration of the control unit in each embodiment will be described in order. The reference numerals of the control units in the first to third embodiments have the embodiment number added to the third digit following "10". The first and second embodiments include one board. In this case, the board is an "end board". The third embodiment includes two boards including one "general board" and one "end board" arranged in a hierarchical manner. In addition, as another embodiment, a configuration including three or more boards will be mentioned.

[0033] (First embodiment) The configuration of the control unit 101 of the first embodiment will be described with reference to Fig. 4 to Fig. 6. Fig. 4 shows a schematic cross-sectional view of the entire unit, and Figs. 5(a) and (b) show enlarged cross-sectional views of the connection between the terminals 45 and the substrate 33. Figs. 6(a) and (b) show plan views of the connector terminal binder 65 and the substrate 33, respectively.

[0034] 4, the control unit 101 is provided with one board 33. The board 33 is a board that is attached to the motor frame 840, and corresponds to the “end board” that is closest to the motor frame 840.

[0035] 6(b), connector terminal holes 345 corresponding to the two connectors 57, 58 are formed toward the center of the board 33. Two or more connector terminals 45 are provided for each connector, and one end of each connector terminal 45 is connected to the board 33. The other end of each connector terminal 45 is inserted through a terminal insertion hole 54 formed in the bottom of the opening of the connectors 57, 58 and exposed at the opening of the connectors 57, 58.

[0036] In this embodiment, unlike the device disclosed in Patent Document 1 (WO 2017 / 068636), the crank-shaped connector terminal is not insert-molded into the top plate of the connector housing. The connector terminals 45 in this embodiment are linear and connected so as to connect the frontages of the connectors 57 and 58 and the board 33 in a straight line in the axial direction of the motor 80.

[0037] 4 illustrates two connector terminals 45 including a communication terminal and a power terminal in vehicle system connector 57, and two sensor terminals in signal system connector 58, following the cross-sectional line in Fig. 3. However, in this embodiment, it is significant that there are two or more connector terminals 45 corresponding to each of connectors 57, 58, and attention is not focused on the type or number of connector terminals 45. The multiple connector terminals 45 corresponding to each of connectors 57, 58 are referred to as a "group of connector terminals."

[0038] 5(a) and (b) show an example of the electrical connection between a terminal and a board, taking the connection point between a connector terminal 45 and a board 33 as an example. In the following specification, when it is self-evident that the term "connection between a terminal and a board" means an electrical connection, the word "electrical" will be omitted as appropriate. A connection portion 38 such as a via hole is provided in the terminal hole 345 of the board 33. The connection portion 38 is electrically connected to the connection portion of an electronic component or another terminal via a conductive pattern, a bus bar, or the like (not shown).

[0039] 5(a), the terminal 45 and the connection portion 38 of the substrate 33 may be soldered by solder WD. As shown in FIG. 5(b), a press-fit connection may be made by pressing a press-fit portion 48 formed at the end of the terminal 45 so as to be elastically deformable into a terminal hole 345.

[0040] 6(a), a resin connector terminal binder 65 holds intermediate portions of the connector terminals 45 so as to bundle together groups of connector terminals 45 corresponding to adjacent vehicle system connectors 57 and signal system connectors 58. A recess 649 may be provided in the unnecessary portion. By bundling the connector terminals 45 with the connector terminal binder 65, the relative positional accuracy of the connector terminals 45 is ensured.

[0041] Furthermore, one or more convex stopper portions 656 are formed on the substrate 33 side of the connector terminal binder 65 to regulate the distance from the substrate 33. The positions of the stopper portions 656 are shown in Fig. 6(a) as examples, but they may be provided in any positions that provide good balance. For convenience, the stopper portions 656 are shown in Fig. 4 without regard to the positions of the cross-sectional lines in Fig. 3.

[0042] The connector terminals 45 are formed with flanges 46 that come into contact with the surface of the connector terminal binder 95 facing the substrate 33. The flanges 46 determine the heightwise positions of the connector terminals 45 relative to the connector terminal binder 95. Therefore, the connector terminals 45 are positioned in the axial direction of the motor 80 via the connector terminal binder 65 whose gap with the substrate 33 is regulated by the stopper portions 656.

[0043] Also, unlike the connector housing 50 which is exposed to the external environment, the connector terminal binder 65 is housed inside the connector housing 50. Therefore, the connector terminal binder 65 is made of a resin material which does not require consideration of weather resistance compared to the connector housing 50, i.e., a resin material with low weather resistance. For example, the connector housing 50 is made of weather-resistant grade PBT, whereas the connector terminal binder 65 is made of non-weather-resistant grade PBT. This allows the material cost to be reduced.

[0044] 4, the resin connector housing 50 has a bottomed cylindrical shape in which an outer tube portion 562 extends from the outer edge of a top plate portion 561 facing the board 33 toward the motor 80. A protrusion 563 formed at the tip of the outer tube portion 562 is inserted into an annular seal groove 843 filled with adhesive. When the connector housing 50 is assembled, a load receiving portion 564 provided at the end of the outer tube portion 562 abuts against a frame outer edge portion 844 of the motor frame 840.

[0045] 3, the top plate portion 561 is provided with the connectors 57, 58 whose frontages face the opposite side to the end substrate 33. The connectors 57, 58 have terminal insertion holes 54 formed at the bottom of their frontages, through which the respective connector terminals 45 can be inserted.

[0046] In a representative embodiment, the central positions of the terminal insertion hole 54 and the connector terminal 45 coincide with each other, and the inner diameter or inner dimension of the rectangular hole of the terminal insertion hole 54 is set to be larger than the outer diameter or outer dimension of the rectangular column of the connector terminal 45. In other words, each connector terminal 45 is fitted with a clearance between it and the inner wall of the terminal insertion hole 54. Even if there is a clearance on the outer periphery of the connector terminal 45, there is no risk of water or foreign matter entering when the harness is inserted into the connectors 57, 58.

[0047] Next, the procedure for assembling the control unit will be described with reference to Figures 7 and 8. As shown in Figure 7, first, the board 33 is fixed to the motor frame 840 with screws 41, and the motor terminals 42 that lead to the motor windings 880 are connected. Next, a bundle of multiple connector terminals 45 bound by a connector terminal binder 65 is assembled to the board 33. At this time, the positional accuracy of the connector terminals 45 in the height direction is ensured by the stopper portions 656 of the connector terminal binder 65 and the flange portions 46 of the connector terminals 45.

[0048] The assembled state is shown in Figure 8. In Figure 8, control unit 101 of this embodiment has a structure in which a bundle of multiple connector terminals 45 assembled integrally with motor 80 is separated from a resin connector housing 50. In the final assembly process, connector housing 50 is placed over substrate 33 to which one ends of multiple connector terminals 45 are connected, and the other ends of connector terminals 45 are inserted into terminal insertion holes 54 and exposed to the openings of connectors 57, 58.

[0049] At the same time, the protrusion 563 of the connector housing 50 is inserted into the seal groove 843 filled with the adhesive, and the outer cylinder portion 562 is fixed to the motor frame 840. Note that since the motor frame 840 is fixed to the motor 80, it may be expressed that the outer cylinder portion 562 is fixed to the motor 80.

[0050] The effects of this embodiment will be described in comparison with a comparative example with reference to Figures 9, 10(a) and 10(b). Figures 9, 10(a) and 10(b) show a schematic relationship between the connector terminals 45 and the terminal insertion holes 54 at the bottom plate portion 540 of the opening of the connector 57. The same is true at the opening of the connector 58.

[0051] 9, the connector terminals 45 are insert- or outsert-molded into a resin connector housing 50. That is, the connector terminals 45 are rigidly fixed to the connector housing 50. When the connector housing 50 is displaced relative to the connector terminals 45 due to the difference in linear expansion coefficient between resin and metal in expansion and contraction due to temperature changes, the connector terminals 45 are displaced following the connector housing 50. This displacement applies excessive stress to the connection portion 38 between the connector terminals 45 and the board 33 and the electronic component ED soldered around the connection portion 38, as shown by the dashed arrow, which may cause breakage of the connection portion 38, failure of the electronic component ED, or the like.

[0052] 10(a), the connector terminals 45 are fitted in the terminal insertion holes 54 with a clearance between them and the inner walls of the terminal insertion holes 54. Therefore, even if the connector housing 50 is displaced relative to the connector terminals 45 due to temperature changes, the connector terminals 45 do not move and remain in their original positions. 54 The displacement of the connector housing 50 due to contact with the inner wall of the connector housing 50 is suppressed to zero.

[0053] In another aspect of this embodiment shown in FIG. 10(b), there is no visible gap between the connector terminal 45 and the inner wall of the terminal insertion hole 54. However, the connector terminal 45 is configured to slide along the inner wall surface of the terminal insertion hole 54 without being dragged due to friction with the inner wall of the terminal insertion hole. For example, a lubricating surface treatment LB is applied to the outer wall of the connector terminal 45, or the terminal insertion hole 54 is formed from a resin material with high self-lubricating properties. Therefore, the connector terminal 45 slides along the inner wall surface of the terminal insertion hole 54 without being dragged due to friction with the inner wall of the terminal insertion hole 54. 54 The contact with the inner wall of the connector terminal 45 suppresses the displacement of the connector terminal 45 following the displacement of the connector housing 50. In this case, the displacement of the connector terminal 45 does not have to be zero, but it is sufficient that the displacement of the connector terminal 45 is attenuated to a certain ratio or less relative to the displacement of the connector housing 50.

[0054] In one aspect and another aspect of this embodiment, the connector terminals 45 are suppressed from being displaced following the relative displacement of the connector housing 50 due to differences in the linear expansion coefficients of the respective members when the temperature changes. This prevents excessive stress from being applied to the connection portions 38 with the board 33 and the electronic components soldered around the connection portions 38 due to the displacement of the connector terminals 45. This ensures the durability of the connection portions 38 with the board 33 and the surrounding soldered joints.

[0055] (Effects of this embodiment) (1) In this embodiment, a bundle of multiple connector terminals 45 bound by a connector terminal binder 65 is separated from a resin connector housing 50. Each connector terminal 45 is inserted into the terminal insertion hole 54 so as to be prevented from being displaced following the connector housing 50 due to contact with the inner wall of the terminal insertion hole 54. This prevents the influence of relative displacement of the connector housing 50 caused by temperature changes from being exerted on the connection portion 38 with the board 33 via the connector terminal 45.

[0056] (2) The connector terminal binder 65 holds the middle portions of the connector terminals 45 so as to bundle the connector terminals 45, thereby ensuring the relative positional accuracy of the connector terminals 45. In addition, the connector terminals 45 are positioned in the axial direction of the motor 80 by the stopper portions 656 of the connector terminal binder 65 and the flange portions 46 of the connector terminals 45. This makes it possible to prevent connector fitting failure.

[0057] (3) Each connector terminal 45 is connected so as to connect in a straight line between the frontage of the connectors 57, 58 and the circuit board 33 in the axial direction of the motor 80. Reducing the length of the connector terminals 45 to a minimum contributes to the miniaturization of the control unit 10 and prevents sliding wear at the contact points with the harness-side female connector.

[0058] (4) The load receiving portion 564 provided at the end of the outer tube portion 562 of the connector housing 50 abuts against the motor frame 840. This prevents stress from concentrating on the fitting portion or the contact portion even if an excessive insertion load is generated when the harness side female connector is inserted into the connectors 57, 58.

[0059] (5) In molding the connector housing 50, which is a large resin part, the number of molding steps is reduced by eliminating the need for insert molding of metal parts such as the connector terminals, etc. Also, by making the connector terminals 45 into a simple, short, straight shape, the part cost is reduced.

[0060] (6) Since the bundle of multiple connector terminals 45 and the resin connector housing 50 are separate, design changes to the openings of the connectors 57, 58 and the terminals of the connector terminals 45 can be flexibly accommodated.

[0061] Second embodiment 11, a control unit 102 according to a second embodiment will be described. In the second embodiment, two connector terminal binders 65 are provided for the connectors 57, 58. Each connector terminal binder 65 holds intermediate portions of the connector terminals 45 so as to bundle a group of connector terminals 45 corresponding to each connector 57, 58.

[0062] Each connector terminal binder 65 is provided with a stopper portion 656, and each connector terminal 45 is formed with a flange portion 46. Therefore, positional accuracy in the height direction of the connector terminals 45 for each of the connectors 57, 58 is ensured.

[0063] When the number of openings of the connectors 57, 58 is large or when the distance between the connectors 57, 58 is wide, providing one common connector terminal binder 65 results in a large size. Therefore, due to the expansion and contraction of the connector terminal binder 65 itself, it becomes difficult to ensure the relative positional accuracy of the multiple connector terminals 45. Therefore, dividing the connector terminal binders 65 into relatively small ones is advantageous in ensuring the relative positional accuracy of the multiple connector terminals 45.

[0064] Third embodiment A control unit 103 according to the third embodiment will be described with reference to Fig. 12. The control unit 103 according to the third embodiment includes two boards, a general board 31 and an end board 33, which are arranged in a hierarchical structure. Regardless of the functions of the electronic components mounted on the boards, the board arranged on the side furthest from the motor frame 840, i.e., the board closest to the connectors 57 and 58, is referred to as the "end board", and one or more boards other than the end board are referred to as the "general board".

[0065] The general board 31 is fixed to the motor frame 840 with screws 41, and a motor terminal 42 is connected to the motor winding 880. The end board 33, which corresponds to the board 33 in the first embodiment, is connected to a plurality of connector terminals 45. For example, the general board 31 is connected to the motor winding 880. 880 An inverter circuit that supplies current to the end board 33 is mounted on the end board 34. Components such as a filter circuit and a communication driver are mounted on the end board 33.

[0066] A plurality of inter-board terminals 43 are connected between the general board 31 and the end board 33. The inter-board terminals 43 are arranged in a region radially outward from the central region in which the connector terminals 45 are arranged. A resin inter-board terminal binder 63 holds intermediate portions of the inter-board terminals 43 so as to bundle the adjacent inter-board terminals 43. However, the inter-board terminal binder 63 does not necessarily have to be provided.

[0067] Similarly to the first embodiment, each connector terminal 45 is inserted into the terminal insertion hole 54 so as to be restrained from being displaced following the connector housing 50 due to contact with the inner wall of the terminal insertion hole 54.

[0068] In the two-board configuration, the axial length of the outer tube portion 562 of the connector housing 50 is longer and larger than in the single-board configuration, so that the displacement during temperature changes becomes more significant. Therefore, the effect of suppressing the displacement of the connector terminals 45 and preventing the generation of excessive stress in the connection portions 38 between the connector terminals 45 and the end board 33 is more effectively exerted.

[0069] (Reference form) A control unit 108 of the reference embodiment will be described with reference to Fig. 13. In the control unit 108 of the reference embodiment, a plurality of connector terminals 45 are insert- or outsert-molded into a connector housing 504. A commercially available movable socket connector 72 is surface-mounted on the substrate 33. When the connector housing 504 is assembled to the motor 80, the plurality of connector terminals 45 are connected to the respective terminals of the socket connector 72.

[0070] When the connector housing 504 is displaced due to expansion / contraction or warping caused by temperature changes, the terminal connection position of the movable socket connector 72 moves flexibly, thereby preventing the occurrence of excessive stress. Therefore, the effect of the displacement of the connector housing 504 is mitigated.

[0071] (Other embodiments) (a) In contrast to the third embodiment, the number of general boards is not limited to one, but may be two or more. The present invention is widely applicable to driving devices having two or more boards in which one or more general boards and one end board are arranged in a hierarchical structure.

[0072] (b) There may be one or more connectors provided on the top plate portion 561 of the connector housing 50. The number of connectors and the use of each connector terminal are not limited to those in the above embodiment, and may be set appropriately according to needs.

[0073] (c) The drive unit 800 of the present invention is not limited to being used as a steering assist motor for an electric power steering device, and may be used as a reaction motor or a steering motor for a steer-by-wire system, or as a drive unit for any other motor.

[0074] 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 present invention. [Explanation of symbols]

[0075] 10(101-103)...Control unit, 33... Substrate (end substrate), 45 Connector terminal, 50 ...connector housing, 54 ...terminal insertion hole, 561 ... top plate portion, 562 ... outer cylinder portion, 57, 58: Connector, 65 Connector terminal binder, 80···motor, 860···stator, 865···rotor.

Claims

1. A drive device comprising a motor (80) including a stator (860) and a rotor (865), and a control unit (10) provided on one side of the motor in the axial direction for controlling the motor, the drive device being integrally configured, a metal motor frame (840) provided at an axial end of the motor on the control unit side; an end board (33) provided on the opposite side of the motor frame from the motor and on the farthest side from the motor frame, the end board having one or more boards on which electronic components constituting the control unit are mounted; a resin connector housing (50) having a bottomed tubular shape including a top plate portion (561) facing the end board and an outer tubular portion (562) extending from an outer edge of the top plate portion toward the motor and having an end fixed to the motor or the motor frame, the top plate portion having one or more connectors (57, 58) with an opening facing the opposite side to the board; a plurality of connector terminals (45) provided for one of the connectors, one end of which is connected to the end board and the other end of which is inserted through a terminal insertion hole (54) formed in the bottom of the frontage of the connector and exposed at the frontage of the connector; one or more resin connector terminal binders (65) for bundling a group of the connector terminals corresponding to each of the connectors, or for holding intermediate portions of the connector terminals so as to bundling a plurality of groups of the connector terminals corresponding to adjacent connectors; Equipped with The connector terminal binder has one or more convex stopper portions (656) formed on the end substrate side to regulate the distance between the end substrate and the connector terminal binder, The connector terminal is formed with a flange portion (46) that abuts against a surface of the connector terminal binder on the end board side, and is positioned in the axial direction of the motor, The connector terminals are inserted into the terminal insertion holes such that the connector terminals are prevented from being displaced in accordance with the connector housing due to contact with an inner wall of the terminal insertion hole.

2. The drive device according to claim 1 , wherein the connector terminal is connected so as to connect a frontage of the connector and the end board in a straight line in an axial direction of the motor.

3. 3. The drive unit according to claim 1, wherein the connector housing is provided with a load receiving portion (564) at an end of the outer cylindrical portion, the load receiving portion abutting against the motor frame.

4. 4. The drive device according to claim 1, wherein the connector terminal binder is made of a resin material having lower weather resistance than the connector housing.

5. The drive device according to any one of claims 1 to 4, further comprising at least one general substrate (31) other than the end substrate, the substrate being arranged in a hierarchical manner.

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