JP7354907B2 - motor - Google Patents

Description

The present invention relates to a motor equipped with a bus bar.

BACKGROUND ART Conventionally, a motor is known in which a winding wound around a stator is connected to an external device via a bus bar. For example, Patent Document 1 discloses that the base of a bus bar to which windings are connected is held on a wiring board, the terminal part of the bus bar that is connected to external wiring is held on a terminal block, and both the wiring board and the terminal block are held on a stator. A motor is described in which both ends of the bus bar are positioned at fixed positions relative to the stator by being fixed.

Patent No. 5992606

By the way, when connecting the terminal section including the tip of the bus bar to an external device outside the motor case, the terminal section cannot be fixed to the stator, so in addition to the member that holds the base of the bus bar, the terminal section must be attached to the motor shaft. A member is required for positioning against. However, since many parts are interposed between the terminal part of the bus bar and the motor shaft, a problem arises in that the positional accuracy of the terminal part with respect to the motor shaft is affected by the accumulation of component tolerances.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a motor that can reduce the influence of component tolerances and accurately position the terminal portion of a bus bar with respect to the motor shaft.

In order to solve the above problems, a motor (1) of the present invention includes a cylindrical stator (3) fixed to a motor case (2), a shaft (8) rotatably supported by the motor case, A three-phase bus bar (6) that connects the winding (5) wound around the stator to an external device, a bus bar holder (14) that fixedly holds the base (61) of the three-phase bus bar, and It includes a terminal holder (15) that holds a three-phase terminal portion (62) including the tip (60) of the bus bar in a fixed position relative to the shaft .
In the three-phase terminal portion, the portion extending parallel to the shaft to the tip of the bus bar is arranged such that wide rectangular portions are arranged radially in a direction parallel to a tangent to the outer circumference of the stator. The terminal holder is formed with three through holes (154) through which portions extending parallel to the shafts of the three-phase terminal portions to the tips of the bus bars are inserted.
The bus bar holder is provided with an assembly part (145) for assembling the holder to the engagement part (32, 33) formed on the outer periphery of the stator . The assembly portion has clearances (C1 , C2, C4, C5 ) between the assembly portion and the stator that allow movement of the bus bar holder relative to the stator at least in the circumferential direction of the stator .

In the motor of the present invention, the busbar holder is assembled movably relative to the stator, so when the terminal section of the busbar is held on the shaft by the terminal holder, the busbar holder moves relative to the stator, and the terminal section is moved to the terminal holder. is held in place with respect to the shaft via. Therefore, the influence of component tolerances can be alleviated, and the terminal portion can be accurately positioned with respect to the motor shaft.

FIG. 1 is a sectional view of a motor showing an embodiment of the present invention. FIG. 3 is an exploded perspective view showing the main parts of the motor. FIG. 2 is a sectional view taken along line III-III in FIG. 1 showing the bus bar holder. It is a perspective view showing the shape of a bus bar. The assembly structure of the stator and the bus bar holder is shown, with (a) being a partial front view and (b) being a sectional view taken along the line Vb-Vb in (a). Another assembly structure of the stator and bus bar holder is shown, in which (a) is a partial front view and (b) is a sectional view taken along the line VIb-VIb in (a). FIG. 7 is a partial cross-sectional view showing still another assembly structure of the stator and the bus bar holder. Still another assembly structure of the stator and the bus bar holder is shown, in which (a) is a partial cross-sectional view, and (b) is a cross-sectional view taken along the line VIIIb-VIIIb in (a).

<One embodiment>
Embodiments of the present invention will be described below based on the drawings.
An embodiment of the present invention will be described based on FIGS. 1 to 5. A motor 1 shown in FIG. 1 is a three-phase brushless motor used in a system that generates brake oil pressure for a vehicle. The motor case 2 includes a main body 21 with a bottom and an end frame 22 that covers an open upper end portion 211 of the main body 21. A cylindrical stator 3 is fixed inside the main body 21, and three-phase windings 5 are wound around a plurality of teeth portions (not shown) of the stator 3. Each winding 5 is electrically connected to external equipment (not shown) via separate bus bars 6.

A rotor 4 is arranged inside the stator 3, and a shaft 8 is fixed to the center of the rotor 4. The upper end of the shaft 8 is supported by the end frame 22 by an upper bearing 9, and the lower end of the shaft 8 is supported by the bottom wall portion 212 of the case body 21 by a lower bearing 11. When power is supplied to the winding 5 from an external device, the rotating magnetic field formed between the stator 3 and the rotor 4 causes the shaft 8 to rotate about its own axis O as a central axis. In this specification, the direction in which the bus bar 6 protrudes in FIG. 1 is referred to as "above" the motor 1, and the opposite side is referred to as "down".

As shown in FIGS. 2 and 3, a bus bar holder 14 made of resin is installed above the stator 3 to securely hold the base portions 61 of the three-phase bus bars 6 together. The bus bar holder 14 includes an opening 142 in the center of an annular portion 141 into which the body 221 of the end frame 22 is fitted. The circumferential edge of the annular portion 141 includes a plurality of notches 143 into which the windings 5 are inserted, a plurality of positioning portions 144 consisting of protrusions or holes for positioning the base 61 of the bus bar 6, and a plurality of positioning portions 144 for positioning the bus bar holder 14 on the stator 3. A plurality of snap-fit assembly pieces 145 are formed to be assembled.

A terminal holder 15 made of resin is installed above the end frame 22 to collectively hold the terminal portion 62 including the tip 60 of the bus bar 6. The terminal holder 15 is provided with a disc part 151 and a cylindrical part 152, the disc part 151 covers the upper surface of the flange part 222 of the end frame 22, and the cylindrical part 152 fits into the body part 221 of the end frame 22 from the inside. It matches. A sleeve 153 is provided upright on the disc portion 151, and the terminal portions 62 of the three-phase bus bar 6 are inserted into the three through holes 154 of the sleeve 153.

A slit 223 into which the terminal portion 62 of the bus bar 6 fits is formed in the flange portion 222 of the end frame 22 . During assembly, the terminal holder 15 is attached to the end frame 22 with the sleeve 153 aligned with the slit 223. At this time, the body portion 221 of the end frame 22 is positioned concentrically with the shaft 8 via the upper bearing 9, and the terminal portion 62 of the bus bar 6 is positioned at a fixed position relative to the shaft 8 by the sleeve 153 of the terminal holder 15.

As one bus bar 6 is shown in FIG. 4, the three-phase bus bar 6 includes, for example, a base portion 61 and a terminal portion 62 that are formed as separate parts from different conductive materials. The base portion 61 and the terminal portion 62 are connected by welding 631 at a joint portion 63, forming the bus bar 6 as a whole into a substantially L-shape. The base 61 is formed with two connecting pieces 612 to which two windings 5 of corresponding phases are connected, and a plurality of locking pieces 613 that are locked to the positioning part 144 of the bus bar holder 14. . The terminal portion 62 includes a portion connected to the base portion 61 and a portion extending parallel to the shaft axis to the tip 60 or upper end of the bus bar 6.

The bus bar holder 14 holding the base 61 is movably assembled to the stator 3 by a plurality of snap-fit assembly pieces 145. As shown in FIGS. 5A and 5B, the core portion 31 of the stator 3 has a plurality of stepped engagement recesses 32 formed on the outer periphery of its upper end. The snap-fit assembly piece 145 is an assembly portion having a claw portion 146 at the lower end or free end, and when the bus bar holder 14 is assembled, the claw portion 146 is elastically deformed and the snap-fit assembly piece 145 is elastically deformed. It is locked in the engagement recess 32 of the stator 3.

When the bus bar holder 14 is assembled, the snap fit assembly piece 145 has a clearance between it and the stator 3 that allows the bus bar holder 14 to move. The clearances C1 and C2 shown in FIG. 5A allow the bus bar holder 14 to move within a plane orthogonal to the shaft axis by forming the assembly piece 145 narrower than the engagement recess 32. A clearance C3 shown in FIG. 5(b) is defined between the claw portion 146 and the bottom surface of the engagement recess 32, and allows the bus bar holder 14 to move in the shaft axial direction.

In the motor 1 having the above configuration, the terminal portion 62 including the tip 60 of the bus bar 6 is held by the terminal holder 15, the base end of the terminal portion 62 is welded to the base portion 61 of the bus bar 6, and the base portion 61 is held by the bus bar holder 14. , a bus bar holder 14 is assembled to the stator 3. Therefore, many parts are interposed between the stator 3 and the terminal section 62, but since the bus bar holder 14 is assembled to the stator 3 via the clearances C1 to C3, the terminal holder 15 is assembled to the end frame 22. Then, the bus bar holder 14 moves in the shaft axial direction and in a plane perpendicular thereto, and the terminal portion 62 is held at a fixed position with respect to the shaft 8 by the terminal holder 15.

Therefore, according to the motor 1 of this embodiment, the influence of the tolerances of many parts can be alleviated, and the terminal portion 62 of the bus bar 6 can be assembled to the shaft 8 with high precision. In particular, since the clearances C1 to C3 are defined between the snap-fit assembly piece 145 of the bus bar holder 14 and the engagement recess 32 of the stator 3, the elasticity of the snap-fit assembly piece 145 can be utilized to It is possible to suppress rattling of the bus bar holder 14 against the bus bar holder 14.

<Other embodiments>
Next, other embodiments of the present invention will be described based on FIGS. 6, 7, and 8. These embodiments differ from the above embodiment in the configuration for assembling the bus bar holder 14 to the stator 3.

(1) In the embodiment shown in FIGS. 6(a) and 6(b), a square hole 33 as an engaging portion is formed in the outer peripheral surface of the core portion 31 of the stator 3, and the snap-fit assembly piece 145 of the bus bar holder 14 A protrusion 147 having a smaller cross-sectional area than the square hole 33 is formed in the square hole 33 . When the bus bar holder 14 is assembled, the snap fit assembly piece 145 is elastically deformed so that the protrusion 147 is locked in the square hole 33, and clearances C4 to C7 having a square annular cross section are defined between them. Clearances C4 and C5 shown in FIG. 6(a) allow the busbar holder 14 to move in a plane orthogonal to the shaft axis, and clearances C6 and C7 shown in FIG. 6(b) allow the busbar holder 14 to move in the shaft axis direction. Make it movable.

(2) In the embodiment shown in FIG. 7, a projecting edge 34 as an engaging portion is formed on the upper end edge of the core portion 31 of the stator 3, and the projecting edge 34 is attached to the snap-fit assembly piece 145 of the bus bar holder 14 from above and below. A clamping portion 148 is formed to clamp it. When the bus bar holder 14 is assembled, the snap-fit assembly piece 145 is elastically deformed and the clamping portion 148 is locked to the protrusion 34 . A clearance C8 that allows the busbar holder 14 to move in the radial direction of the shaft 8 and clearances C9 and C10 that allow the busbar holder 14 to move in the shaft axial direction are provided between the projecting edge 34 and the clamping part 148. It is defined.

(3) In the embodiment shown in FIGS. 8(a) and 8(b), a circular pin hole 35 is recessed in the upper surface of the core portion 31 of the stator 3, and a circular pin hole 35 is formed in the lower surface of the bus bar holder 14. A loose-fit assembly pin 149 with a large area is provided protrudingly. The loose fit assembly pin 149 is an assembly part for assembling the bus bar holder 14 to the stator 3, and when inserted into the pin hole 35, the shaft axis line is inserted between the pin hole 35 and the loose fit assembly pin 149. A clearance C11 in the direction and clearances C12 to C15 in a plane orthogonal to the shaft axis are defined.

(4) The motor 1 shown in FIG. 1 is a three-phase brushless motor used in a brake hydraulic pressure generation system of a vehicle. Motors used for other purposes may also be used.
The present invention is not limited to the embodiments described above, and the shapes and configurations of each part can be changed as appropriate without departing from the spirit of the invention.

1...Motor, 3...Stator, 4...Rotor, 5...Winding,
6... Bus bar, 60... Tip, 61... Base, 62... Terminal part,
8... Shaft, 14... Bus bar holder, 145... Snap fit assembly piece,
149... Loose fit assembly pin, 15... Terminal holder,
C1 to C15... Clearance.

Claims (2)

a cylindrical stator (3) fixed to a motor case (2);
a shaft (8) rotatably supported by the motor case;
a three-phase bus bar (6) that connects the winding (5) wound around the stator to an external device;
a busbar holder (14) that fixedly holds the base (61) of the three-phase busbar;
a terminal holder (15) that holds a three -phase terminal portion (62) including a tip (60) of the three-phase bus bar in a fixed position with respect to the shaft;
In the three-phase terminal portion, a portion extending parallel to the shaft to the tip of the bus bar is arranged such that wide rectangular portions are arranged radially in a direction parallel to a tangent to the outer periphery of the stator; The terminal holder is formed with three through holes (154) into which portions of the three-phase terminal portion extending parallel to the shaft and extending to the tip of the bus bar are inserted;
The bus bar holder is provided with an assembly part (145) for assembling the bus bar holder to the engagement part (32, 33) formed on the outer periphery of the stator,
The motor (1) has a clearance (C1 , C2, C4, C5 ) between the assembly section and the stator that allows movement of the bus bar holder with respect to the stator at least in the circumferential direction of the stator . The motor according to claim 1, wherein the assembly section includes a snap-fit assembly piece (145) that is elastically deformed and locked onto the engagement section.

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