JP2024042380A - Busbar, circuit board and motor - Google Patents

Abstract

[Problem] To provide a bus bar, a substrate, and a motor that can save space inside a motor with a simple structure. [Solution] A bus bar 60 includes a metal member 61, and the metal member 61 includes a terminal 63 (or 64) and an engagement portion 65a that can engage with and electrically connect to another metal member 61 stacked on the metal member 61 in a predetermined direction. [Selected Figure] Figure 7

Description

The present invention relates to a busbar, a substrate, and a motor.

Conventionally, in a motor, a bus bar is used as a member that is interposed between a lead wire from a coil and a conducting wire connected to an external power source or a circuit board, and supplies a large amount of current to the lead wire (for example, see Patent Document 1) ).

Japanese Patent Application Publication No. 2002-171708

When using a bus bar, for example, if the number of coils increases, a plurality of wiring circuits are required, which tends to make the wiring design complicated. As a result, the space occupied by the bus bar within the motor increases.

An example of an object of the present invention is to provide a bus bar, a board, and a motor that have a simple structure and can save space within the motor.

The above problem is solved, for example, by one embodiment of the present invention below. A bus bar according to one aspect of the present invention includes:
Equipped with metal parts,
The metal member is
terminal and
An engaging portion capable of engaging and electrically connecting another metal member stacked on the metal member in a predetermined direction.

1 is a perspective view schematically showing the appearance of a motor according to an embodiment of the present invention. 2 is a longitudinal sectional view of a motor according to an embodiment of the present invention, and corresponds to the AA sectional view in FIG. 1. FIG. 2 is a cross-sectional view of a motor according to an embodiment of the present invention, and corresponds to the BB sectional view in FIG. 1. FIG. 1 is a perspective view schematically showing the internal structure of a motor according to an embodiment of the present invention, with a housing removed from the motor. 1 is a plan view schematically showing the internal structure of a motor according to an embodiment of the present invention, with a housing removed from the motor. FIG. 1 is a perspective view schematically showing the structure of a substrate according to an embodiment of the present invention. FIG. 1 is a perspective view schematically showing the structure of a bus bar that constitutes a substrate according to an embodiment of the present invention. 1 is a perspective view showing a schematic structure of a bus bar constituting a substrate according to an embodiment of the present invention; FIG. 1 is a perspective view schematically showing an engagement structure of a bus bar that constitutes a substrate according to an embodiment of the present invention. FIG. 1 is a perspective view schematically showing a structure in which a plurality of substrates are stacked according to an embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the motor of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view schematically showing the structure of a motor 10 according to an embodiment of the present invention, FIG. 2 is a longitudinal cross-sectional view of the motor 10, and FIG. 3 is a cross-sectional view of the motor 10. Note that FIG. 2 corresponds to a sectional view taken along the AA line in FIG. 1 along a virtual plane including the axis x constituting the rotational axis of the motor 10, and FIG. This corresponds to the BB sectional view in FIG.

In the description of this embodiment, in the direction of the axis x, the side in the direction of the arrow a is defined as the upper side a, and the side in the direction of the arrow b is defined as the lower side b (see Figures 1 and 2). Note that the upper side a and the lower side b do not necessarily correspond to the up-down relationship in the direction of gravity. Also, in the radial direction cd of the motor 10 perpendicular to the axis x, the side in the direction of the arrow c away from the axis x is defined as the outer circumferential side c, and the side in the direction of the arrow d toward the axis x is defined as the inner circumferential side d (see Figures 2 and 3). Furthermore, in the circumferential direction ef about the axis x, the clockwise direction e and the counterclockwise direction f are defined as viewed from the upper side a (see Figure 3).

As shown in FIGS. 1 to 3, the motor 10 according to the present embodiment includes a shaft 11 constituting a rotating shaft, a rotor 20 that is fixed to the shaft 11 and rotates together with the shaft 11, and a rotor 20 that surrounds the rotor 20. The motor includes a stator 30 and a housing 40 that is fixed to the stator 30 and accommodates some or all of the components of the motor 10 therein. That is, the shaft 11 and rotor 20 rotate relative to the housing 40 and stator 30, which are fixed to an external device (not shown) in which the motor 10 is incorporated.

The rotor 20 has a magnet 22 fixed to the outer circumferential surface of a rotor core 21 made of a magnetic material. The stator 30 has a coil 32 wound around a stator core 31 made of a magnetic material, and is fixed to a housing 40. The motor 10 according to this embodiment is a type of inner rotor type brushless motor.

The housing 40 has a cylindrical housing body 41 that is open on the upper side a and closed on the lower side b, and a cover 42 that covers the opening on the upper side a of the housing body 41. The housing main body 41 includes an annular bottom portion 41a, a protruding portion 41b that protrudes downward in a cylindrical shape from the inner circumferential edge of the bottom portion 41a, and an outer circumferential portion 41c that extends in a cylindrical manner toward the upper side a from the outer circumferential edge of the bottom portion 41a. , is provided. The stator 30 is fixed to the inner peripheral surface of the outer peripheral portion 41c.

On the other hand, the cover 42 includes an annular flat plate part 42a, a protruding part 42b adjacent to the inner circumferential edge of the flat plate part 42a and protruding downward in a cylindrical shape, and a cylindrical protruding part 42b adjacent to the outer circumferential edge of the flat plate part 42a. and an outer peripheral portion 42c protruding toward the lower side b. The outer peripheral part 41c of the housing body 41 and the outer peripheral part 42c of the cover 42 are fitted and fixed (fastened), and the housing 40 is completed. The rotor 20 and stator 30 are all housed inside this housing 40.

As shown in FIG. 1, the flat plate portion 42a of the cover 42 is provided with a circular opening 42d at its center and one opening 42e extending circumferentially around the opening 42d. The shaft 11 projects from the opening 42d to the upper side a. The opening 42e extends circumferentially around the axis x. Referring to FIG. 2, the shaft 11 is rotatably supported by two bearings 12 and 13 fixed to the housing 40. One bearing 12 is attached to the inside of the protrusion 41b of the housing body 41, and the other bearing 13 is attached to the inside of the protrusion 42b of the cover 42, for example, by press fitting.

In the rotor 20, the rotor core 21 is formed from a laminate of a plurality of magnetic materials stacked in the axis x direction. In particular, as shown in FIG. 3, the shaft 11 is inserted into the hole 21a of the rotor core 21 and fixed. An annular magnet 22 is fixed to the outer peripheral surface of the stator core 21.

On the other hand, in the stator 30, the stator core 31 is formed from a laminate of magnetic material such as silicon steel plate. As shown in FIG. 3, the stator core 31 has an annular portion 31a arranged on the outer circumferential side c, and multiple magnetic pole portions 31b formed to extend from the annular portion 31a to the inner circumferential side d. The multiple magnetic pole portions 31b can be separated from the annular portion 31a at a boundary line R defined along their base ends defined on the outer circumferential side d. In other words, the stator core 31 is a split core. The ends of the magnetic pole portions 31b on the inner circumferential side d protrude on both sides in the circumferential direction ef.

A coil 32 is wound around each of the plurality of magnetic pole parts 31b. An insulator 33 made of an insulator is interposed between the stator core 12 and the coil 32, and the insulator 33 insulates the stator core 31 and the coil 32. As shown in FIG. 2, for example, one leader wire 32a is drawn out from each coil 32, and the leader wire 32a stands up toward the upper side a. A current is supplied to or extracted from the coil 32 through this lead wire 32a. In this embodiment, the number of coils 32 is twelve.

In the radial direction CD, the end of the magnetic pole portion 31b of the stator core 31 faces the magnet 22 of the rotor core 21 via the magnetic gap G. When current is supplied to the coil 32 of the stator 30, the rotor 20 rotates around the axis x due to interaction with the magnetic field generated by the magnet 22 of the rotor 20. In this way, the shaft 11 attached to the rotor 20 can rotate relative to external equipment (not shown) attached to the stator 30 and the housing 40.

4 is a perspective view schematically showing the internal structure of the motor 10 with the housing 40 removed from the motor 10, and FIG. 5 is a perspective view schematically showing the internal structure of the motor 10 with the housing 40 removed from the motor 10. FIG. Referring to FIGS. 2, 4, and 5 together, the motor 10 includes one or more substrates (hereinafter referred to as "busbar substrates") housed within the housing 40 between the cover 42 of the housing 40 and the stator 30. ) 50. In this embodiment, three busbar substrates 50 are stacked in the axis x direction. The busbar board 50 is arranged on the outer peripheral side c of the shaft 11.

In particular, as shown in FIG. 2, each busbar substrate 50 includes one or more busbars 60 that extend annularly around the axis x, and an annular resin member 70 that covers the busbars 60. In this embodiment, for example, two bus bars 60, 60 are stacked in the axis x direction. In this embodiment, the motor 10 includes three busbar boards 50, so a total of six busbars 61 are stacked in the axis x direction. Bus bar 60 is formed from a conductive material including a metal material such as copper or aluminum. The resin member 70 is formed from an insulating material containing a resin material.

FIG. 6 is a perspective view schematically showing the structure of the busbar board 50 according to the present embodiment, and FIG. 7 is a perspective view schematically showing the structure of two busbars 60, 60 of the busbar board 50 according to the present embodiment. FIG. 8 is a perspective view schematically showing the structure of a single bus bar 60 according to the present embodiment. First, referring to FIG. 8, the bus bar 60 includes a metal member (hereinafter referred to as a "metal ring") 61. The metal ring 61 includes an annular ring body 62, one or more terminals (hereinafter referred to as "internal connection terminals") 63 that protrude from the ring body 62, and one or more terminals that similarly protrude from the ring body 62. A plurality of terminals (hereinafter referred to as "external connection terminals") 64 are provided.

The ring body 62 extends along a virtual plane orthogonal to the axis x, and is formed of a flat member. The internal connection terminal 63 extends from the inner surface 62d of the ring body 62 to the outer circumferential side c in the direction toward the outer surface 62c in the radial direction CD. The internal connection terminal 63 extends along the virtual plane in which the ring body 62 extends. In this embodiment, two internal connection terminals 63, 63 are arranged at angular intervals of 180 degrees around the axis x.

Each of the internal connection terminals 63 is a fork-shaped terminal and has a pair of arms (hereinafter referred to as "terminal arms") 63a, 63a extending parallel to each other in the radial direction. As is clear from FIG. 4, each internal connection terminal 63 accommodates the lead wire 32a of the coil 32 between the pair of terminal arms 63a, 63a and is electrically connected to the lead wire 32a. The lead wire 32a accommodated between the pair of terminal arms 63a, 63a is fixed to the internal connection terminal 63 by soldering, crimping the pair of terminal arms 63a, 63a, or by pressing the lead wire 32a between the pair of terminal arms 63a, 63a.

On the other hand, one external connection terminal 64 extends from the outer surface 62c of the ring body 62 to the inner surface 62d in the radial direction cd toward the inner periphery d. The external connection terminal 64 is electrically connected to an external device (not shown). The external connection terminal 64 includes, for example, a protruding piece 64a protruding from the inner periphery end of the ring body 62 toward the inner periphery d in the radial direction cd, and an upright piece 64b standing upright from the inner periphery end of the protruding piece 64a to the upper side a. The protruding piece 64a protrudes from the inner periphery end of the ring body 62 within an imaginary plane in which the ring body 62 extends. The upright piece 64b is formed from a plate piece extending along an imaginary plane extending parallel to the axis x direction. In this embodiment, the external connection terminal 64 is disposed at the same angular position around the axis x as one internal connection terminal 63.

The metal ring 61 includes one or more engagement pieces 65 . In this embodiment, two engaging pieces 65, 65 protrude from the inner circumferential end of the ring body 62 toward the inner circumferential side d in the radial direction cd. The engagement piece 65 extends flatly along the imaginary plane in which the ring body 62 extends. In this embodiment, one engagement piece 65 is arranged at the same angular position as the other internal connection terminal 63 around the axis x. The other engagement piece 65 is arranged at an angle of 90 degrees in the counterclockwise direction f from the one engagement piece 65 around the axis x.

Each of the engagement pieces 65 includes an engagement portion, that is, a hole 65a that passes through the engagement piece 65 along a central axis defined parallel to the axis x. The hole 65a is, for example, a cylindrical space. A spiral groove, that is, a female thread groove 65b, is formed on the inner peripheral surface of the hole 65a. Note that such a hole 65a is formed by, for example, burring. Therefore, the hole 65a is also formed within the cylindrical edge 65c rising from the surface of the engagement piece 65.

Next, referring to FIG. 7, in the busbar board 50 according to this embodiment, two busbars 60, 60 are stacked in the axis x direction. That is, the center defined by the ring body 62 of the upper bus bar 60 and the center defined by the ring body 62 of the lower bus bar 60 coincide with the axis x. In this embodiment, the bus bar 60 on the upper side a is rotated 90 degrees clockwise e with respect to the bus bar 60 on the lower side b and is stacked on top of the bus bar 60 on the lower side b. The other engaging piece 65 of the bus bar 60 on the upper side a and the one engaging piece 65 of the bus bar 60 on the lower side b are aligned.

A member, that is, a screw 66 is screwed into the hole 65a of the other engagement piece 65 and the female thread groove 65b of the hole 65a of the one engagement piece 65. As shown in FIG. 9, the screw 66 is, for example, a rod-shaped body, and a spiral groove, that is, a male thread groove 66a, is formed on the outer peripheral surface of the screw 66. In this way, the two bus bars 60, 60 are engaged with each other via the screws 66. The screw 66 is made of a conductive material including a metal material such as copper or aluminum, for example. As a result, the two bus bars 60, 60 that are engaged with each other via the screws 66 are electrically connected to each other.

Returning to FIG. 7, in the two mutually engaged bus bars 60, 60, the four internal connection terminals 63 are arranged at equal angular intervals of 90 degrees around the axis x. Furthermore, the two external connection terminals 64 are arranged at angular intervals of 90 degrees around the axis x. Note that one engagement piece 65 of the upper bus bar 60 and the other engagement piece 65 of the lower bus bar 60, which are not used for engagement of the two bus bars 60, 60, have an angular interval of 180 degrees around the axis x. Arranged in Further, around the axis x, the angular position of the other engaging piece 65 of the lower bus bar 60 matches the angular position of one of the internal connection terminals 63 and the external connection terminals 64 of the upper bus bar 60.

Next, referring to FIG. 6, two mutually engaged bus bars 60, 60 are covered with an annular resin member 70. As shown in FIG. Specifically, while the resin member 70 completely covers the two ring bodies 62, 62, the internal connection terminal 63, the external connection terminal 64, and the engagement piece 65 are arranged outside the resin member 70. Insert molding is performed to manufacture such a bus bar board 50. Specifically, two bus bars 60, 60 that are engaged with each other via male screws 66 are installed in a mold, and a resin material is injected into the mold, so that they are engaged with each other. A resin member 70 is integrally formed on the bus bars 60, 60.

FIG. 10 is a perspective view schematically showing a state in which three busbar substrates 50 according to the present invention are stacked. Two adjacent busbar substrates 50, 50 are bonded to each other using, for example, an adhesive or the like. Each of the three busbar substrates 50 is rotated and arranged at angular intervals of 30 degrees around the axis x with respect to the other adjacent busbar substrates 50. For example, the positions of the engaging pieces 65, 65 that engage with each other on the busbar substrate 50 are between the busbar substrate 50 on the lower side b and the intermediate busbar substrate 50, and between the busbar substrate 50 on the upper side a of the intermediate busbar substrate 50. and are shifted at angular intervals of 30 degrees in the clockwise direction e. As a result, as shown in FIG. 5, the 12 internal connection terminals 63 of the three busbar boards 60 are arranged at equal angular intervals of 30 degrees around the axis x. In this way, each of the internal connection terminals 63 is electrically connected to each of the lead wires 32a of the coil 32.

On the other hand, the six external connection terminals 64 of the three busbar boards 50 are also arranged at angular intervals of 30 degrees. As shown in FIGS. 1 and 3, the external connection terminal 64 protrudes upward from the opening 42e of the cover 42a into the external space of the motor 10. In this way, the external connection terminal 64 is electrically connected to an external device (not shown).

In the motor 10 as described above, the busbars 60, 60 of the busbar board 50 are stacked in the axis x direction and can engage with each other. Specifically, the bus bars 60, 60 can be electrically connected to each other via the screws 66. Therefore, the space inside the motor 10 can be saved with a simple structure. Furthermore, since the busbar board 50 has a structure in which busbars 60 having the same shape are stacked at different angles around the axis x, a simplified operation is sufficient to form a plurality of circuits. Further, since the structure is simple, an increase in manufacturing cost of the motor 10 can be suppressed.

Note that in the above-described busbar board 50, the busbars 60 are engaged with each other through the screws 66, but instead of the screws 66, for example, a rod-shaped body is press-fitted into the hole 65a to form the hole. The portions 65a, 65a may be engaged with each other. Further, although the engagement piece 65 is disposed outside the ring body 62, the hole 65a may be formed in the ring body 62 and the formation of the engagement piece 65 may be omitted.

Further, in the above-described busbar board 50, the busbars 60, 60 are engaged with each other via the screws 66. The bus bars 60, 60 may be electrically independent from each other instead of being aligned. By making the busbars 60, 60 electrically independent from each other within the busbar board 50, it is possible to provide two independent circuit busbars within one busbar board 50. As a method for removing members such as the screws 66, it is possible to remove the members such as the screws 66 after the busbar board 50 shown in FIG. 60 may be integrally formed with a resin member 70.

Furthermore, in the embodiment described above, three busbar substrates 50 are stacked on top of each other, but the number of busbar substrates 50 can be increased or decreased by increasing or decreasing the number of internal connection terminals 63 or external connection terminals 64 of one busbar 60. is also possible. Furthermore, between the three busbar substrates 50, the holes (engaging portions) 65a are engaged with each other across the busbar substrates 50 via members such as screws 66, so that two circuits as a whole or It can also be a one-circuit bus bar. At this time, the busbars 60, 60 may be made electrically independent within each busbar substrate 50, and then the holes (engaging portions) 65a may be engaged with each other across the busbar substrate 50. In this case, the holes (engaging portions) 65a may be aligned so that engagement across the busbar substrate 50 is possible. A hole (engaging portion) 65a may be provided separately so that engagement across the busbar substrate 50 is possible. Note that the bus bar 60 does not need to have a continuous ring shape, and may have a shape in which a part of the ring is missing.

Furthermore, in the above example, the two busbars 60, 60 constitute one busbar board 50, but the number of busbars included in one busbar board is not limited to two, and may be three or more. do not have. By setting the number of busbars included in one busbar board to three or more, and engaging the engaging parts of the included busbars in any combination, one circuit or two or more circuits of busbars can be installed in one busbar board. It is possible to have a configuration including. For example, the number of busbars included in one busbar board is four, and the busbars are divided into two sets, each pair consisting of two busbars adjacent in the stacking direction, and the engaging portions of the busbars in each set are engaged with each other. This allows a configuration in which two circuit busbars are included in one busbar board.

In addition, the configuration of the motor 10 other than the busbar substrate 50 is not limited to that of the above embodiment, and the present invention can be applied to any type of motor. Therefore, although the above embodiment uses an inner rotor type motor as an example, the present invention can also be applied to outer rotor type motors, and can be applied to brush motors as well as brushless motors.

In addition, those skilled in the art can modify the motor of the present invention as appropriate based on conventionally known knowledge. As long as such modifications still have the structure of the present invention, they are, of course, included within the scope of the present invention.

DESCRIPTION OF SYMBOLS 10... Motor, 11... Shaft, 12... Bearing, 13... Bearing, 20... Rotor, 21... Rotor core, 21a... Hole part, 22... Magnet, 30... Stator, 31... Stator core, 31a... Annular part, 31b... Magnetic pole part , 32... Coil, 32a... Lead wire, 33... Insulator, 40... Housing, 41... Housing main body, 41a... Bottom, 41b... Protruding part, 41c... Outer circumferential part, 42... Cover, 42a... Flat plate part, 42b... Protruding part , 42c...Outer circumference, 42d...Opening, 42e...Opening, 50...Busbar board, 60...Busbar, 61...Metal member (metal ring), 62...Ring body, 63...Terminal (internal connection terminal), 63a... Arm (terminal arm), 64... Terminal (external connection terminal), 64a... Projecting piece, 64b... Upright piece, 65... Engaging piece, 65a... Engaging part (hole), 65b... Spiral groove (female thread groove) ), 65c...Cylindrical edge 65, 66...Member (rod-shaped body, screw), 66a...Spiral groove (male thread groove), 70...Resin member.

Claims (12)

Equipped with metal parts,
The metal member is
terminal and
A bus bar comprising: an engaging portion capable of engaging and electrically connecting another metal member stacked on the metal member in a predetermined direction. The bus bar according to claim 1, wherein the engaging portion is a hole. The bus bar according to claim 2, wherein a spiral groove is formed in the inner circumferential surface of the hole. the metal member is annular;
2. The terminal according to claim 1, wherein the terminal extends in the direction from the inner surface to the outer surface of the metal member, or extends in the direction from the outer surface to the inner surface of the metal member. bus bar. comprising the busbar according to claim 1 and one or more other busbars different from the busbar,
The substrate, wherein the bus bar and the other bus bar are stacked in the predetermined direction. The board according to claim 5, wherein the engaging portion of the bus bar and the engaging portion of the other bus bar are engaged with each other via a member. The engagement portion of the bus bar and the engagement portion of the other bus bar each include a hole,
The board according to claim 6, wherein the engaging portion of the bus bar and the engaging portion of the other bus bar are engaged with each other via a member. The engagement portion of the bus bar and the engagement portion of the other bus bar each include a spiral groove formed on the inner surface of the hole,
The member has an outer circumferential surface, and a spiral groove is formed on the outer circumferential surface,
Claim 7: The spiral groove formed on the inner surface of the engaging portion of the bus bar and the engaging portion of the other bus bar is screwed into the spiral groove formed on the outer peripheral surface of the member. The substrate described in . The board according to claim 5 or 6, wherein the metal member of the bus bar and the metal member of the other bus bar are covered with a resin member. A substrate according to claim 5 or 6;
a stator having a plurality of coils;
a terminal of the bus bar and a terminal of the other bus bar are electrically connected to the plurality of coils. The motor according to claim 10, wherein the metal members of the busbar and the metal members of the other busbar are covered with a resin member. shaft and
a rotor fixed to the shaft;
the substrate is annular;
The motor according to claim 10, wherein the shaft is located on the inner circumferential side of the substrate in the radial direction.

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