CN116472659A - Motor device - Google Patents

Abstract

In the motor device, the electrical connection between the terminals of the bus bar and the terminals of the terminal unit can be achieved without using a large-sized device. A motor device is provided with: a stator accommodated in the housing and wound with a coil; a rotor that rotates with respect to the stator; a bus bar unit 50 disposed at one side of the stator in an axial direction and including a plurality of bus bars; and a terminal 61 for supplying a driving current to the coil. The bus bar includes: an arc part formed in an arc shape; and a power connection portion 51e protruding radially outward of the circular arc portion, the terminal 61 being disposed so as to straddle the inner side and the outer side of the housing, the power connection portion 51e and the terminal 61 being disposed so as to overlap each other in the axial direction of the rotor, and being electrically connected by a bolt 28.

Description

Motor device

Technical Field

The present invention relates to a motor device.

Background

As a three-phase motor device mounted on a motorcycle or the like, a motor device is known in which a bus bar is interposed between a coil wound around each stator and a terminal unit (terminal unit) facing a connector connected to an external power source. As an example of the motor device, patent document 1 describes a motor device in which terminals of bus bars and terminals included in a terminal unit are welded.

Prior art literature

Patent literature

Patent document 1: japanese patent application laid-open No. 2010-41871

Disclosure of Invention

Problems to be solved by the invention

In the motor device described in patent document 1, the terminals of the bus bar and the terminals of the terminal unit are welded.

However, in the welding process of the terminals of the bus bar and the terminals, the gap or the positional deviation between the terminals of the bus bar and the terminals when the terminal unit is assembled is large due to the deviation of the respective parts, and therefore it is difficult to establish welding in a state where the terminals of the bus bar and the terminals are in contact.

Further, in the case of using welding, a welder or an image recognition camera is required, and therefore, there is a problem that the apparatus becomes large.

Therefore, a connection structure other than soldering is required for connection between the terminals of the bus bar and the terminals of the terminal unit.

The purpose of the present invention is to provide a motor device that can electrically connect the terminals of a bus bar to the terminals of a terminal unit without using a large-sized device.

Technical means for solving the problems

The motor device of the invention comprises: a stator accommodated in the housing and wound with a coil; a rotor that rotates with respect to the stator; a bus bar unit disposed at one axial side of the stator and including a plurality of bus bars; and a terminal for supplying a driving current to the coil, wherein the bus bar includes: an arc part formed in an arc shape; and a power supply connection portion protruding radially outward of the circular arc portion, the terminal being disposed so as to straddle the inner side and the outer side of the housing, the power supply connection portion and the terminal being disposed so as to overlap each other in the axial direction of the rotor, and being electrically connected to each other by a fastening member.

ADVANTAGEOUS EFFECTS OF INVENTION

By the present invention, the terminals of the bus bar can be electrically connected with the terminals of the terminal unit without using a large-sized device.

Drawings

Fig. 1 is an external perspective view showing the structure of a motor device (brushless motor) according to an embodiment of the present invention.

Fig. 2 is a plan view showing an internal structure of the motor apparatus shown in fig. 1 with a cover member removed.

FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2.

Fig. 4 is a perspective view showing a bus bar unit and a driving connector incorporated in the motor device shown in fig. 1.

Fig. 5 is a partial plan view showing a structure of a connection portion between a bus bar unit and a driving connector in the motor device shown in fig. 1.

FIG. 6 is a sectional view taken along line B-B of FIG. 5.

Fig. 7 is a partial perspective view showing the shape of the front end of the power connection portion of the bus bar shown in fig. 6.

Fig. 8 is a partial perspective view showing the shape of the distal end of the terminal of the drive connector shown in fig. 6.

Fig. 9 is a partial sectional view taken along line C-C of fig. 5.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The motor device shown in fig. 1 to 3 is a brushless motor 10 used as a drive source for an electric motorcycle or the like (a driven object). Specifically, the brushless motor 10 is provided in a vehicle body frame, and drives an axle of a drive wheel via a chain or a belt. The brushless motor 10 may be directly provided to the axle of the drive wheel.

The brushless motor 10 includes a housing 20 forming the outer contour of the brushless motor 10. The case 20 includes a case body 21 made of aluminum and formed in a substantially bottomed tubular shape, and a cover member 22 made of aluminum and formed in a substantially circular plate shape. Here, the lid member 22 closes the opening side (upper side in fig. 1 and 3) of the case main body 21 via a gasket 23 (see fig. 1 and 3) functioning as a sealing member.

As shown in fig. 3, a motor unit 40 is housed inside the casing 20. The motor unit 40 includes a stator 41 fixed to the inside of the housing main body 21, and a rotor 42 rotating radially inward of the stator 41 with a minute gap (air gap). That is, the stator 41 is accommodated in the housing 20.

The stator 41 has a stator core 41a formed by stacking a plurality of steel plates (magnetic materials) and having a substantially cylindrical shape. A plurality of teeth (not shown) are provided on the radial inner side of the stator core 41a, and coils 41c corresponding to three phases of U phase, V phase, and W phase are wound around the teeth via insulators 41b including a non-magnetic material such as plastic, and the like, respectively, by concentrated windings. That is, a plurality of coils 41c are wound around the stator 41.

Further, an annular busbar unit 50 is provided on one axial side (upper side in the axial direction SD of fig. 3) of the stator 41. The bus bar unit 50 includes a plurality of bus bars 51. The bus bar unit 50 is electrically connected to the front end portion Tb of each of the U-phase power supply terminal TU, the V-phase power supply terminal TV, and the W-phase power supply terminal TW (see fig. 4). The bus bar unit 50 has a function of distributing drive currents to the coils 41c corresponding to the three phases of the U-phase, the V-phase, and the W-phase. That is, the U-phase power supply terminal TU, the V-phase power supply terminal TV, and the W-phase power supply terminal TW supply driving currents to the coils 41c corresponding to the three phases U-phase, V-phase, and W-phase, respectively.

The rotor 42 rotates with respect to the stator 41. The rotor 42 includes a rotor body 42a formed in a substantially cylindrical shape by stacking a plurality of steel plates (magnetic materials). A rotation shaft 42b including a round steel rod is fixed to the rotation center of the rotor body 42a. That is, the rotation shaft 42b rotates together with the rotor body 42a. A plurality of magnets 42c formed in a substantially plate shape are provided in the rotor body 42a. The plurality of magnets 42c are arranged so that N poles and S poles alternately appear in the circumferential direction of the rotor body 42a.

However, the structure is not limited to the so-called "built-in permanent magnet (Interior Permanent Magnet, IPM) structure in which a plurality of magnets 42c are embedded in the rotor main body 42a as described above, and a so-called" surface permanent magnet (SurfacePermanent Magnet, SPM) structure in which a magnet (not shown) is mounted on the surface of the rotor main body 42a may be employed.

A sensor magnet 42d formed in a substantially circular plate shape is fixed to one side in the axial direction of the rotary shaft 42b forming the rotor 42. The sensor magnet 42d detects the rotation state of the rotor 42 (rotation shaft 42 b). The sensor magnet 42d faces the rotation sensor 44a provided on the sensor substrate 44 in the axial direction of the rotor 42.

Further, one side in the axial direction of the rotation shaft 42b is rotatably supported by a first ball bearing BB1 mounted on a bearing holder 43. In contrast, the other axial side (lower side in fig. 3) of the rotation shaft 42b is rotatably supported by a second ball bearing BB2 attached to the housing main body 21.

The case main body 21 includes a bottom wall portion 21a formed in a substantially circular plate shape. A bearing mounting portion 21b and a seal mounting portion 21c formed in a substantially cylindrical shape are integrally provided in a central portion of the bottom wall portion 21a. The bearing mounting portions 21b and the seal mounting portions 21c are coaxially arranged. The bearing mounting portion 21b is provided inside the housing main body 21, and an outer ring of the second ball bearing BB2 is mounted radially inward of the bearing mounting portion 21 b. In contrast, the seal mounting portion 21c is provided outside the housing main body 21, and a rubber lip seal LS is mounted radially inside the seal mounting portion 21c.

The inner ring of the second ball bearing BB2 is attached to the other axial side of the rotary shaft 42b, and the lip seal LS contacts the outer periphery of the rotary shaft 42b at a portion outside the housing main body 21 than the second ball bearing BB 2. Thereby, rainwater, dust, or the like is prevented from entering the inside of the housing 20.

Further, four fixing legs 21d (only three are shown in fig. 1 and 2) are provided on the outer side of the case main body 21 in the radial direction of the bottom wall portion 21a. The fixing legs 21d are integrally provided at equal intervals (90 degree intervals) around the bottom wall portion 21a, and are fixed to a body frame or the like forming a skeleton of the motorcycle via bolts.

Further, the case main body 21 includes a cylindrical wall portion 21e formed in a substantially cylindrical shape. The other axial side of the cylindrical wall portion 21e is integrally provided radially outward of the bottom wall portion 21a. The stator core 41a is pressed into the radial inner side of the cylindrical wall portion 21e and is firmly fixed by an adhesive or the like. Further, a plurality of cooling fins 21f are integrally provided on the radial outer side of the cylindrical wall portion 21e, and the plurality of cooling fins 21f radiate heat of the motor unit 40 (stator core 41 a) generated by the driving of the brushless motor 10 to the outside of the housing main body 21.

Further, the housing main body 21 includes a polygonal wall portion 24. The polygonal wall portion 24 is integrally provided on one axial side (upper side in fig. 3) of the cylindrical wall portion 21e so as to be coaxial with the cylindrical wall portion 21e. Further, as shown in fig. 2, the polygonal wall portion 24 is formed in a substantially regular hexagonal shape when the housing main body 21 is viewed from the axial direction side.

Specifically, the polygonal wall portion 24 includes a first side portion 24a, a second side portion 24b, a third side portion 24c, a fourth side portion 24d, a fifth side portion 24e, and a sixth side portion 24f, the six side portions 24a to 24f forming a substantially regular hexagon. The polygonal wall 24 is provided with an opening 24g, and the stator 41 or the rotor 42 (motor unit 40) is assembled into the housing main body 21 through the opening 24 g. The opening 24g is sealed by the cover member 22 via the gasket 23.

A drive connector 25 as a terminal unit is mounted on the first side 24a, and the drive connector 25 is provided on one side in the axial direction of the housing 20. The driving connector 25 has a connector block 25a made of a resin material such as plastic, and the driving connector 25 including the connector block 25a is fixed to the first side 24a of the polygonal wall 24 shown in fig. 2 by a bolt (another fastening member) 53 for fixing shown in fig. 5 described later.

The connector block 25a is disposed outside the housing 20, specifically, protrudes radially outward of the polygonal wall 24. Further, each terminal 61 is provided inside the connector block 25 a. Specifically, the base ends Tt of the U-phase power supply terminal TU, the V-phase power supply terminal TV, and the W-phase power supply terminal TW are exposed in the connector block 25a (see fig. 4). The front end portions Tb (see fig. 4) of the U-phase power supply terminal TU, the V-phase power supply terminal TV, and the W-phase power supply terminal TW are electrically connected to the busbar unit 50 housed in the case 20.

Specifically, the distal ends Tb of the U-phase power supply terminal TU, the V-phase power supply terminal TV, and the W-phase power supply terminal TW are electrically connected to the power supply connection portions 51e (see fig. 4) of the U-phase, V-phase, and W-phase bus bars 51, respectively, by fastening members. The electrical connection between each terminal 61 and each power supply connection portion 51e by the fastening member will be described in detail later.

As shown in fig. 2, the base end portion Tt of the U-phase power supply terminal TU is electrically connected to the other end side of the U-phase electric wire EU, one end side of which is electrically connected to the controller CU. The base end portion Tt of the V-phase power supply terminal TV is electrically connected to the other end side of the V-phase electric wire EV, one end side of which is electrically connected to the controller CU. Further, the base end portion Tt of the W-phase power supply terminal TW is electrically connected to the other end side of the W-phase wire EW, one end side of which is electrically connected to the controller CU. Thereby, a driving current is supplied to each coil 41c of the stator 41.

As shown in fig. 3 and 5, each terminal 61 including the U-phase power supply terminal TU, the V-phase power supply terminal TV, and the W-phase power supply terminal TW is disposed so as to extend inside and outside the polygonal wall 24 of the case 20 in a plan view.

Here, the connector block 25a faces in a direction intersecting the axial direction of the housing 20 (upper side of fig. 2). That is, the other end sides of the U-phase electric wire EU, the V-phase electric wire EV, and the W-phase electric wire EW are respectively in directions intersecting the axial direction of the housing 20 with respect to the connection direction of the drive connector 25. The connector block 25a is fixed to the first side 24a via a rubber seal member SM (see fig. 3). Thereby, rainwater, dust, or the like is prevented from entering the inside of the housing 20 from the portion of the connector block 25 a.

As shown in fig. 2, a protrusion 26 protruding radially outward of the housing 20 is integrally provided on the polygonal wall 24. Specifically, the protruding portion 26 protrudes radially outward of the housing 20 from a second side portion 24b provided beside the first side portion 24a. When the housing 20 is viewed from one axial side, the protruding portion 26 is formed in a substantially triangular shape, and includes an opening portion 26a and a bottom wall 26b formed in a substantially triangular shape. The protruding portion 26 has a first side wall 26c and a second side wall 26d that are raised from the bottom wall 26b toward one side in the axial direction of the housing 20. The second side 24b also stands up from the bottom wall 26b toward one side in the axial direction of the housing 20.

In this way, the protruding portion 26 is surrounded by the bottom wall 26b, the first side wall 26c, the second side wall 26d, and the second side portion 24b, and the connecting space SP is formed inside the protruding portion 26. That is, the connecting space SP is provided on one axial side of the housing 20.

The connection space SP is a portion into which the controller-side connector portion 47 side of the board harness 45 in the longitudinal direction enters. When the controller-side connector portion 47 is connected to the board connector 27, the connection space SP has a function of guiding (guiding) the controller-side connector portion 47 to the board connector 27. In this way, the controller-side connector portion 47 can be easily connected to the substrate connector 27 at the time of assembling the brushless motor 10.

Here, the first side wall 26c is disposed on a substantially extended line of the first side 24a. The second side wall 26d is disposed on a substantially extended line of the third side 24 c. This suppresses the protrusion 26 from protruding significantly radially outward of the case 20. The opening 26a of the protruding portion 26 is also sealed by the cover member 22 via the gasket 23.

As shown in fig. 1 to 3, the cover member 22 includes a main cover portion 22a that closes the opening 24g of the polygonal wall portion 24, and a sub-cover portion 22b that closes the opening 26a of the protruding portion 26. The main cover 22a and the sub cover 22b are integrated, the main cover 22a is formed in a substantially circular plate shape, and the sub cover 22b is formed in a substantially triangular plate shape.

The cover member 22 is firmly fixed to the housing main body 21 by seven fixing bolts BT distributed in the circumferential direction thereof. When the cover member 22 is fixed to the case main body 21, the gasket 23 is interposed therebetween.

A connector fixing portion 26e is integrally provided on the first side wall 26c of the protruding portion 26 so as to protrude radially outward of the housing 20. The connector 27 for the substrate is mounted on the connector fixing portion 26e. Here, the board connector 27 is also provided on one side in the axial direction of the housing 20, similarly to the driving connector 25.

The board connector 27 is formed in a predetermined shape from a resin material such as plastic, and includes a fixing plate portion 27a formed in a substantially flat plate shape. The fixing plate portion 27a is fixed to the connector fixing portion 26e by a pair of first screws S1. A rubber sealing member (not shown) is provided between the fixing plate portion 27a and the connector fixing portion 26e. Thereby, rainwater, dust, or the like is prevented from entering the interior of the housing 20 from the portion of the substrate connector 27.

The board connector 27 includes an inner connecting portion (not shown) and an outer connecting portion 27c formed in a substantially box shape. The inner connecting portion is provided on the connector fixing portion 26e side of the fixing plate portion 27a, and is disposed inside the housing 20. In contrast, the outer connecting portion 27c is provided on the opposite side of the fixing plate portion 27a from the connector fixing portion 26e, and is disposed outside the housing 20. A plurality of conductive members (not shown) are embedded in the substrate connector 27 by insert molding or the like.

Here, the controller-side connector portion 47 of the board harness 45 is connected to the inside connection portion of the board connector 27 in the connection space SP inside the protruding portion 26. In contrast, the outer connection portion 27c of the board connector 27 is connected to the other end side of the board wire SE (see fig. 2) having one end side electrically connected to the controller CU via a connector connection portion (not shown). That is, the other end side of the substrate wire SE is electrically connected to one end side of the conductive member provided in the substrate connector 27.

As shown in fig. 1 and 2, the connector block 25a disposed outside the housing 20 and the outside connection portion 27c also disposed outside the housing 20 face the same direction (upper side in fig. 2) as the direction intersecting the axial direction of the housing 20. When the housing 20 is viewed from a direction intersecting the axial direction of the housing 20, the drive connector 25 and the board connector 27 are arranged in a row and in close proximity to each other in a direction intersecting the axial direction of the housing 20. This improves the handling properties of the U-phase electric wire EU, V-phase electric wire EV, W-phase electric wire EW, and substrate electric wire SW with respect to the brushless motor 10, and makes it possible to easily connect these electric wires EU, EV, EW, SE to the drive connector 25 and the substrate connector 27, respectively.

Further, when the housing 20 is viewed from a direction intersecting the axial direction of the housing 20, the drive connector 25 and the board connector 27 are provided within a range of the axial dimension of the rotor 42, that is, within a range of the axial dimension of the rotary shaft 42b (see fig. 3). Thereby, the axial dimension of the brushless motor 10 is shortened, and miniaturization of the brushless motor 10 is achieved.

As shown in fig. 2 and 3, an aluminum bearing holder 43 formed in a substantially regular hexagonal plate shape is provided on one axial side (upper side in fig. 3) of the housing main body 21. The bearing holder 43 is disposed radially inward of the polygonal wall portion 24 formed in a substantially regular hexagon, and holds the first ball bearing BB1. Specifically, the first ball bearing BB1 is mounted on a holding cylinder 43a formed at the central portion of the bearing holder 43. Further, the holding cylinder 43a protrudes toward the other axial side (lower side in fig. 3) of the housing main body 21, and enters the radial inner side of the bus bar unit 50. Thereby, the axial dimension of the brushless motor 10 can also be shortened.

The bearing holder 43 is firmly fixed to one axial side of the housing main body 21 by a total of six first fixing bolts B1. Further, the total of six first fixing bolts B1 are distributed so as to be located near the corners of the bearing holder 43, and are fastened from the axial side of the housing main body 21. This effectively suppresses deformation of the bearing holder 43, and ensures positional accuracy of the first ball bearing BB1. Therefore, the rotor 42 can smoothly rotate. Further, the first fixing bolt B1 is provided inside the housing 20, but even if the first fixing bolt is loosened and disengaged in the tightened state, the first fixing bolt does not come off to the rotor 42 side, and damage to the rotating portion can be reliably prevented.

Further, a clamp fixing portion 43b formed in a substantially plate shape is provided near the protruding portion 26 on the opposite side of the bearing holder 43 from the rotor 42 side. The clamp fixing portion 43B is disposed between the adjacent first fixing bolts B1 and protrudes toward one axial side (near front side in fig. 2) of the housing 20. A clip member 49 fixed to the board harness 45 is fixed to the clip fixing portion 43b.

Further, an annular support plate 43c is provided at a center portion of the bearing holder 43 on the side opposite to the rotor 42 side, and the annular support plate 43c prevents the first ball bearing BB1 from coming off the holding cylinder 43a. Specifically, the support plate 43c presses the outer ring of the first ball bearing BB1 with its radially inner portion. This ensures smooth operation of the first ball bearing BB1.

The support plate 43c is fixed to the bearing holder 43 by a total of four second fixing bolts B2 (only three are shown in fig. 2) arranged at equal intervals (90 degree intervals) in the circumferential direction of the support plate 43 c. The second fixing bolt B2 is also provided in the housing 20, but does not fall off to the rotor 42 side even when the second fixing bolt is loosened in the tightened state, and damage to the rotating portion can be reliably prevented.

Further, four support columns 43d in total are provided around the first ball bearing BB1 on the opposite side of the bearing holder 43 from the rotor 42 side. The support columns 43d protrude at a predetermined height on one axial side of the housing 20, and a sensor substrate 44 is fixed to a front end portion thereof. That is, the total of four support columns 43d support the sensor substrate 44.

Specifically, the support columns 43d are arranged at equal intervals (90 degree intervals) around the first ball bearing BB1, and the sensor substrate 44 is fixed to the pair of support columns 43d arranged on the diagonal line by the pair of second screws S2. The second screw S2 is also provided in the housing 20, but is not detached to the rotor 42 side even if the fastened state is loosened and detached, and damage to the rotating portion can be reliably prevented.

The sensor substrate 44 supported by the total of four support columns 43d is provided on one axial side of the housing 20, and becomes a printed substrate (printed circuit board (printed circuit board, PCB)) formed in a substantially square shape. Further, in a central portion of the sensor substrate 44, a rotation sensor 44a including a magneto-resistive element is provided. The rotation sensor 44a faces the sensor magnet 42d fixed to one side of the rotation shaft 42b in the axial direction of the housing 20 with a small gap therebetween (see fig. 3). Thereby, the rotation sensor 44a detects the rotation state (rotation direction, rotation speed, etc.) of the rotation shaft 42b.

The sensor board 44 is provided with a board-side connection portion 44b to which the board-side connector portion 48 of the board harness 45 is connected. As shown in fig. 2, the substrate-side connector portion 48 can be easily connected to the substrate-side connection portion 44b by the substrate-side connection portion 44b provided on the sensor substrate 44 facing the connection space SP of the protruding portion 26.

Here, the board harness 45 is provided between the sensor board 44 and the board connector 27, and the board harness 45 has a function of electrically connecting the controller CU (see fig. 2) and the sensor board 44 in the housing 20. Accordingly, the detection signal of the rotation sensor 44a is transmitted to the controller CU via the board harness 45 and the board electric wire SE.

As shown in fig. 3 and 4, the busbar unit 50 provided on one side in the axial direction of the stator 41 is formed in a substantially annular shape as viewed in the axial direction. A holding cylinder 43a is disposed radially inward of the busbar unit 50 in a state where the brushless motor 10 is assembled. Therefore, the first ball bearing BB1 and a part of the rotation shaft 42b are also disposed radially inward of the bus bar unit 50.

The bus bar unit 50 includes three bus bars 51 formed in a substantially C-shape in an axial direction, and these bus bars 51 are used for U-phase, V-phase, and W-phase, respectively, corresponding to the coils 41C (see fig. 3) of the U-phase, V-phase, and W-phase (three phases). Further, the three bus bars 51 are respectively formed in the same shape.

The bus bar unit 50 includes a bus bar support 52 for holding the bus bars 51 for the U-phase, the V-phase, and the W-phase. The bus bar support portion 52 corresponds to an insulator in the present invention, and is formed in a ring shape by injection molding a resin material such as plastic. Specifically, as shown in fig. 4, the bus bar support portion 52 holds the three bus bars 51 coaxially so as to be shifted by a predetermined amount (approximately 30 degrees) in the circumferential direction and to be in a state of being non-contact with each other (a state of not being short-circuited).

Further, the three bus bars 51 are overlapped in an insulating state with a minute gap therebetween in the axial direction of the bus bar unit 50. Therefore, the deformation of each bus bar 51 is a phenomenon to be surely eliminated in the manufacture of the bus bar unit 50. In other words, in order to reduce the axial dimension of the bus bar unit 50 to achieve miniaturization of the entire brushless motor 10, it is also necessary to precisely shape the bus bar 51 so as not to generate deformation.

Each of the bus bars 51 includes a first arc portion (arc portion) 51a and a second arc portion (arc portion) 51b formed in an arc shape as viewed in the axial direction of the bus bar 51, and a power supply connection portion 51e protruding radially outward of each of the first arc portion 51a and the second arc portion 51b.

In detail, the bus bar 51 includes a first circular arc portion 51a formed in a substantially circular arc shape when viewed in the axial direction of the bus bar 51. The first circular arc portion 51a occupies most of the bus bar 51. The bus bar 51 includes a second arc portion 51b formed in a substantially circular arc shape when viewed in the axial direction of the bus bar 51. The second circular arc portion 51b has the same radius of curvature as the first circular arc portion 51a.

The coil connecting portions 51c are integrally provided on both sides in the longitudinal direction of the first circular arc portion 51a and on one side in the longitudinal direction of the second circular arc portion 51b, respectively. That is, three coil connection portions 51c are provided in total in the bus bar 51. The interval between the pair of coil connection portions 51c provided in the first circular arc portion 51a is 180-degree interval. The distance between the coil connecting portion 51c on the other side in the longitudinal direction of the first circular arc portion 51a and the coil connecting portion 51c of the second circular arc portion 51b is 90 degrees.

Further, it is formed that: the front end portion Tp on the front end side in the longitudinal direction of the power supply connection portion 51e is electrically connected to the front end portion Tb of the U-phase power supply terminal TU, the V-phase power supply terminal TV, and the W-phase power supply terminal TW.

Here, the connection between each terminal 61 and the power supply connection portion 51e corresponding to each terminal 61 according to the present embodiment by the fastening member will be described in detail. The U-phase power supply terminal TU (61) and the power supply connection portion 51e are arranged so as to overlap each other in the axial direction RD of the rotor 42 shown in fig. 3. As shown in fig. 5, the U-phase power supply terminal TU (61) and the power supply connection portion 51e are electrically connected by screwing a bolt 28 for fixing as a fastening member. Similarly, the V-phase power supply terminal TV (61) and the power supply connection portion 51e are arranged to overlap each other in the axial direction RD of the rotor 42. As shown in fig. 5, the V-phase power supply terminal TV (61) and the power supply connection portion 51e are electrically connected by screwing the bolt 28 as a fastening member. The W-phase power supply terminal TW (61) and the power supply connection portion 51e are arranged to overlap each other in the axial direction RD of the rotor 42. As shown in fig. 5, the W-phase power supply terminal TW (61) and the power supply connection portion 51e are electrically connected by screwing the bolt 28 as a fastening member.

Here, the connection structure between each terminal 61 and the power supply connection unit 51e will be described in detail with a typical example of the connection structure between the V-phase power supply terminal TV (61) and the power supply connection unit 51e. However, the connection structure between the U-phase power supply terminal TU (61) and the power supply connection portion 51e and the connection structure between the W-phase power supply terminal TW (61) and the power supply connection portion 51e are also the same as the connection structure between the V-phase power supply terminal TV (61) and the power supply connection portion 51e.

As shown in fig. 6, in the connection structure between the V-phase power supply terminal TV (61) and the power supply connection portion 51e, the front end side end portion of the power supply connection portion 51e is overlapped on the front end side end portion of the V-phase power supply terminal TV (61), and the bolt 28 inserted from above the power supply connection portion 51e through the through hole 51i of the power supply connection portion 51e is screwed to the screw groove 61e shown in fig. 8 of the V-phase power supply terminal TV (61). Thus, the V-phase power supply terminal TV (61) is electrically connected to the power supply connection unit 51e.

In the fastening structure shown in fig. 6, the power supply connection portion 51e is disposed on the V-phase power supply terminal TV (61), and the bolt 28 inserted into the through hole 51i of the power supply connection portion 51e is screwed into the screw groove 61e of the V-phase power supply terminal TV (61). Specifically, the V-phase power supply terminal TV (61) has a screw hole 61d shown in fig. 8, and the power supply connection portion 51e has a through hole 51i shown in fig. 7 having a larger diameter than the screw hole 61 d. The bolt 28 inserted into the through hole 51i of the power supply connection portion 51e is screwed into the screw groove 61e of the V-phase power supply terminal TV (61), whereby the V-phase power supply terminal TV (61) and the power supply connection portion 51e are electrically connected.

The relationship between the V-phase power supply terminal TV (61) and the power supply connection unit 51e may be reversed. That is, it may be: the V-phase power supply terminal TV (61) is superimposed on the power supply connection portion 51e, and the power supply connection portion 51e and the V-phase power supply terminal TV (61) are electrically connected by screwing a bolt 28 inserted from above the V-phase power supply terminal TV (61) through a through hole of the V-phase power supply terminal TV (61) to a screw groove formed in the power supply connection portion 51e.

As described above, in the brushless motor 10 of the present embodiment, the connection between each terminal 61 and the power connection portion 51e corresponding to each terminal 61 is performed by screwing using the bolts 28, and thus the power connection portion (terminal) 51e of the bus bar 51 can be electrically connected to each terminal 61 of the terminal unit (driving connector 25) without using a large-sized device such as welding.

Further, by completing the electrical connection between each terminal 61 and the power connection portion 51e corresponding to each terminal 61 by screwing the fastening member such as the bolt 28, a larger connection area can be ensured than in the case of welding. Thereby, the current density of the current flowing in the connection portion between the terminal 61 and the power supply connection portion 51e can be reduced. Specifically, since the current flowing through the brushless motor 10 mounted on a motorcycle or the like is also large, the resistance increases when the area is locally reduced at the connection portion of the terminal or the like and the current density is increased. Therefore, the following is also considered: the heat generation in the connection portion may be large and exceed the heat resistant temperature of the coil coating film during operation, or the heat generation may be large and adversely affect the insert molding resin. Therefore, the current density in the connection portion or the like of the terminal is preferably low. In the case of soldering, a necessary and sufficient connection area (cross-sectional area) may not be ensured in a connection portion of a terminal or the like.

However, in the brushless motor 10 of the present embodiment, the electrical connection between the terminal 61 and the power supply connection portion 51e is performed by screwing the fastening member, whereby a large connection area in the connection portion or the like can be ensured, and the current density of the current flowing in the connection portion can be reduced. This suppresses the heat generation in the connection portion from increasing beyond the heat-resistant temperature of the coil coating film during operation, and further suppresses the adverse effect on the insert molding resin due to the large heat generation.

In addition, by completing the electrical connection between the terminal 61 and the power supply connection portion 51e by screwing the fastening member without performing soldering, a soldering machine or a camera for image recognition is not required, and the number of devices used can be reduced.

In the brushless motor 10 of the present embodiment, the terminal 61 and the power supply connection portion 51e are electrically connected by screwing the fastening member, and therefore, welding is not performed, and therefore, the use of a machine tool for determining the welding position of the terminal 61 can be reduced, and the driving energy of the welding machine for welding can be reduced. As a result, it is possible to achieve, among the sustainable development targets (SustainableDevelopment Goals, SDGs) established by the united nations, particularly the target 7 and the target 13.

As shown in fig. 6, a combustion portion 61f formed by combustion processing and tapping (tap) processing is provided in a portion of the V-phase power supply terminal TV (61) where a screw groove 61e (see fig. 8) is formed. This can further improve the coupling force of the screw portion of the screw groove 61e of the V-phase power supply terminal TV (61) and the coupling strength of the terminal 61 and the power supply connection portion 51e.

In addition, in assembling the terminal 61 and the power connection portion 51e, when the front end side end portion of the V-phase power supply terminal TV (61) is overlapped with the front end side end portion of the power connection portion 51e, the V-phase power supply terminal TV (61) is inserted from the outside of the housing main body 21 toward the bus bar unit 50 inside of the housing main body 21, and the front end side end portion of the V-phase power supply terminal TV (61) is overlapped with the front end side end portion of the power connection portion 51e. At this time, in the brushless motor 10 of the present embodiment, as shown in fig. 7, a chamfer 51h is formed in a front end side peripheral edge 51f (peripheral edge on the front end Tp side) of a surface (facing surface 51 d) of the power supply connection portion 51e overlapping the terminal 61 shown in fig. 8.

On the other hand, a chamfer portion 61c is formed on a front end side peripheral edge portion 61b (peripheral edge portion on the front end Tb side) of a surface (facing surface 61 a) of the terminal 61 overlapping the power supply connection portion 51e. Thus, even if the terminal 61 and the power supply connection portion 51e collide with each other due to the assembly deviation in the axial direction RD of the rotor 42 shown in fig. 3 at the time of assembly of the terminal 61 and the power supply connection portion 51e, the terminal 61 and the power supply connection portion 51e can be assembled. That is, the chamfer 51h is formed at the front end side peripheral edge 51f of the facing surface 51d of the power supply connection portion 51e, and the chamfer 61c is formed at the front end side peripheral edge 61b of the facing surface 61a of the terminal 61. Thus, when the V-phase power supply terminal TV (61) is inserted from the outside of the case main body 21 and the end portion on the front end Tb side of the V-phase power supply terminal TV (61) is overlapped with the end portion on the front end Tp side of the power supply connection portion 51e, the terminal 61 and the power supply connection portion 51e can be smoothly overlapped by the chamfer portion 51h of the power supply connection portion 51e and the chamfer portion 61c of the V-phase power supply terminal TV (61). Therefore, even if the terminal 61 and the power supply connection portion 51e collide with an obstacle, the terminal 61 and the power supply connection portion 51e can be assembled.

As shown in fig. 5, a connector block (connector) 25a for holding each terminal 61 is provided outside the polygonal wall 24 of the housing 20 (see fig. 3). Further, the mounting portion 25b of the connector block (connector) 25a is disposed at a position between two power supply connection portions 51e disposed adjacently in the circumferential direction AD of the first circular arc portion 51a (see fig. 4) among the power supply connection portions 51e included in each of the three bus bars 51 (see fig. 4). That is, in the configuration shown in fig. 5, the plate-like mounting portion 25b provided to the connector block 25a is arranged between two power supply connection portions 51e arranged adjacently in the circumferential direction AD. The plate-shaped mounting portion 25b is inserted from the outside to the inside of the polygonal wall portion 24 of the housing 20 and is disposed between the adjacent two power supply connection portions 51e.

As shown in fig. 9, the plate-like mounting portion 25b is screwed to the housing main body 21 of the housing 20 via a bolt (another fastening member) 53. Specifically, the bolt 53 is passed through the insertion member 54 embedded in the mounting portion 25b, and the bolt 53 is screwed with the screw groove 21g formed in the housing main body 21. That is, the connector block 25a is screwed to the housing main body 21 via the plate-shaped mounting portion 25b by the bolts 53.

By disposing the mounting portion 25b of the connector block 25a of the terminal unit between the two power supply connection portions 51e adjacently disposed in the circumferential direction AD in this manner, the terminal unit can be mounted to the housing main body 21 with efficient use of space.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit and scope of the present invention. In the above embodiment, the case where the brushless motor 10 including the bus bar unit 50 is applied to the drive source of the electric motorcycle or the like is shown, but the present invention is not limited thereto. For example, the present invention is applicable to a small-sized mobile drive source such as an electric wheelchair or an electric cart, a drive source such as a joint of an arm robot, and a drive source of a power steering (power steering) device.

In the above embodiment, the case where the combustion portion is formed by subjecting the terminal 61 to the combustion process has been described, but the combustion process may not be performed in the case where the thickness of the terminal 61 is large and the length of the portion where the screw groove 61e is formed can be sufficiently ensured.

In addition, the material, shape, size, number, arrangement position, and the like of each component in the embodiment are arbitrary as long as the present invention can be achieved, and are not limited to the embodiment.

Description of symbols

10: brushless motor (Motor device)

20: shell body

21: casing body

21a: bottom wall portion

21b: bearing mounting part

21c: sealing installation part

21d: fixed foot

21e: cylindrical wall part

21f: cooling fin

21g: thread groove

22: cover member

22a: main cover part

22b: auxiliary cover part

23: gasket ring

24: polygonal wall

24a: first edge part

24b: second edge part

24c: third side part

24d: fourth side part

24e: fifth edge part

24f: sixth edge portion

24g: an opening part

25: driving connector (terminal unit)

25a: connector block (connector)

25b: mounting part

26: protruding part

26a: an opening part

26b: bottom wall

26c: first side wall

26d: a second side wall

26e: connector fixing part

27: connector for substrate

27a: fixing plate part

27c: outside connecting part

28: bolt (fastening component)

40: motor unit

41: stator

41a: stator core

41b: insulation body

41c: coil

42: rotor

42a: rotor body

42b: rotary shaft

42c: magnet

42d: sensor magnet

43: bearing retainer

43a: holding cylinder

43b: clamp fixing part

43c: supporting plate

43d: support column

44: sensor substrate

44a: rotation sensor

44b: substrate-side connection portion

45: wire harness for substrate

47: controller-side connector part

48: substrate-side connector part

49: clamp component

50: bus bar unit

51: bus bar

51a: a first arc part

51b: a second arc part

51c: coil connecting part

51d: facing surfaces

51e: power supply connection part (terminal)

51f: front end side peripheral edge portion

51h: chamfering part

51i: through hole

52: bus bar support

53: bolt (another fastening component)

54: insert member

61: terminal

61a: facing surfaces

61b: front end side peripheral edge portion

61c: chamfering part

61d: threaded hole

61e: thread groove

61f: combustion part

AD: circumferential direction

B1: first fixing bolt

B2: second fixing bolt

BB1: first ball bearing

BB2: second ball bearing

BT: fixing bolt

CU: controller for controlling a power supply

EU: u-phase wire

EV: v-phase electric wire

EW: w-phase wire

LS: lip seal

RD: axial direction

S1: first screw

S2: second screw

SD: axial direction

SE: wire for substrate

SM: sealing member

SP: space for connection

Tb: front end part

Tp: front end part

Tt: base end portion

TU: u-phase power supply terminal

TV: v-phase power supply terminal

TW: w-phase power supply terminal

Claims (4)

1. A motor device is provided with:

a stator accommodated in the housing and wound with a coil;

a rotor that rotates with respect to the stator;

a bus bar unit disposed at one axial side of the stator and including a plurality of bus bars; and

a terminal for supplying a driving current to the coil,

the motor apparatus is characterized in that,

the bus bar includes:

an arc part formed in an arc shape; and

a power supply connection part protruding radially outward of the circular arc part,

the terminals are disposed across the inside and outside of the housing,

the power supply connection portion and the terminal are disposed to overlap in an axial direction of the rotor, and are electrically connected by a fastening member.

2. The motor apparatus according to claim 1, wherein a chamfer is formed on a front end side peripheral edge portion of a surface of the power supply connection portion overlapping the terminal end,

a chamfer is formed on the front end side peripheral edge of the surface of the terminal overlapping the power supply connection part.

3. A motor apparatus according to claim 1 or 2, wherein a screw hole is formed in the terminal end,

a through hole having a larger diameter than the screw hole is formed in the power supply connection portion,

the fixing bolt passing through the through hole is screwed with a thread groove formed in the screw hole.

4. A motor apparatus according to any one of claims 1 to 3, wherein a connector holding the terminal is provided outside the housing,

a mounting portion of the connector is disposed between two of the power supply connection portions disposed adjacently in a circumferential direction of the circular arc portion among the power supply connection portions included in each of the plurality of bus bars,

the mounting portion is fixed to the housing via another fastening member.