Patent Description:
In recent years, various brushless motors have been developed which do not use mechanical contacts such as brushes and commutators. For example, Patent Document <NUM> discloses a configuration related to a pump device including a brushless motor.

<CIT> relates to a control unit and driving apparatus using the same. In this respect, power terminals of power modules are described which are magnetically coupled to power-output terminals and power-input terminals. A heat sink has parallel surfaces, which are in parallel to the power modules and the power terminals. A magnetic field, which is generated by electric current flowing through switching devices and the power terminals, is cancelled by a magnetic field, which is generated by eddy current flowing in the heat sink.

<CIT> relates an electronically commutated motor and describes that in the case of an electronically commutated motor with a stator which has a plurality of individual coils which are connected to a motor winding via a connection element, the connection element is formed like a printed circuit board and has conductor tracks which interconnect the individual coils, the conductor tracks being welded to assigned individual coils.

<CIT> discloses an electrical machine, in particular an electronically commutated EC motor, and a method of manufacturing such a machine, having a pole pot in which a stator and a rotor are accommodated, and axially on the open side of the pole pot a plug housing with an integrated connection plug is arranged, wherein the plug housing is enclosed over its entire circumference by a metal cover which is tightly connected to the pole pot, wherein the connection plug projects outwardly through a recess in the metal cover axially opposite the rotor, and the plug housing is sealed with respect to the metal cover by means of a sealing ring.

<CIT> discloses that an electric motor includes: a brushless motor; and a control device that is coupled integrally to an end of a motor case in an axial direction. The control device includes: a bus bar unit main body that has a base unit with a plurality of bus bars wired thereinside and has a connector unit provided integrally on the base unit and led out to an outside of a housing; a motor drive unit that drives the brushless motor; and a motor control unit that controls the motor drive unit. The motor drive unit is attached to a first main surface of the base unit while the motor control unit is attached to a second main surface of the base unit.

By the way, an electric actuator to be mounted on a vehicle is desired to be miniaturized due to limitation of a space for mounting the electric actuator. However, in the pump device described in Patent Document <NUM>, a driving coil and a circuit board are connected to each other through a terminal pin arranged along an axial direction of a rotor by soldering one end of the terminal pin having the other end electrically connected to the driving coil to the circuit board. Therefore, in the axial direction of the rotor, it is required to secure a space for soldering the terminal pin to the circuit board in addition to a space for arranging the terminal pin. Thus, it is difficult to reduce the size of the entire pump device in the axial direction of the rotor. Patent Document <NUM> does not disclose any solution for solving such a problem.

In view of the foregoing, it is an object of at least one embodiment of the present disclosure to provide an on-vehicle brushless motor device that can be miniaturized in the axial direction of the rotor and a method of manufacturing the same.

Further embodiments of the present invention are described in the dependent claims.

According to at least one embodiment of the present disclosure, it is possible to provide an on-vehicle brushless motor device which can be miniaturized in the axial direction of the rotor and a method of manufacturing the same.

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It is intended, however, that unless particularly specified, dimensions, materials, shapes, relative positions and the like of components described in the embodiments shall be interpreted as illustrative only and not limitative of the scope of the present invention.

For example, an expression of relative or absolute arrangement such as "in a direction", "along a direction", "parallel", "orthogonal", "centered", "concentric" and "coaxial" shall not be construed as indicating only the arrangement in a strict literal sense, but also includes a state where the arrangement is relatively displaced by a tolerance, or by an angle or a distance whereby it is possible to achieve the same function.

For example, an expression of an equal state such as "same", "equal" and "uniform" shall not be construed as indicating only the state in which the feature is strictly equal, but also includes a state in which there is a tolerance or a difference that can still achieve the same function.

Further, for example, an expression of a shape such as a rectangular shape or a cylindrical shape shall not be construed as only the geometrically strict shape, but also includes a shape with unevenness or chamfered corners within the range in which the same effect can be achieved.

First, description will be provided on a schematic configuration of an on-vehicle brushless motor device <NUM> according to an embodiment of the present disclosure. <FIG> is a view schematically illustrating a configuration example of the on-vehicle brushless motor device <NUM> according to an embodiment of the present disclosure. <FIG> is a partial enlarged view illustrating a region II illustrated by a broken line in <FIG>.

As illustrated in <FIG> and <FIG>, the on-vehicle brushless motor device <NUM> is mounted, for example, on a vehicle as an electric oil pump (EOP) that is an electric oil supply device to supply oil for lubrication, cooling, or working fluid to an engine, a clutch, or the like. The on-vehicle brushless motor device <NUM> includes a brushless motor <NUM> that does not use a mechanical contact such as a brush or a commutator, and an electronic substrate <NUM> for controlling driving of the brushless motor <NUM>.

The brushless motor <NUM> is an inner rotor type brushless motor including, for example, a rotor <NUM> and a stator <NUM> including a plurality of coils <NUM> arranged around the rotor <NUM>.

The rotor <NUM> is arranged inside the stator <NUM> and formed, in a coaxial manner, of an output shaft <NUM> (rotary shaft), a cylindrical rotor core (not illustrated) arranged in the outer circumference of the output shaft <NUM>, and a ring-shaped magnet <NUM> (see <FIG>) magnetized in multiple poles (e.g., six poles) and fixed to the rotor core along the outer circumference thereof. In the exemplary embodiment illustrated in <FIG>, plate-like S-pole magnet portions 15a and plate-like N-pole magnet portions 15b are alternately arranged in the circumferential direction, and six magnet portions 15a and 15b (three magnet portions 15a and three magnet portions 15b) are arranged to form a substantially hexagonal shape when viewed in the axial direction of the rotor <NUM>. A pump rotor (not illustrated) such as a gear (not illustrated) for transporting oil is connected to the output shaft <NUM> to be rotatable together with the output shaft <NUM>.

Hereinafter, the axial direction of the rotor <NUM> is referred to as an "axial direction X". In addition, a direction from the electronic substrate <NUM> toward the brushless motor <NUM> (a direction from the opposite side to the output side of the brushless motor <NUM> toward the output side of the brushless motor <NUM>) in the axial direction X is referred to as "downward direction" or simply "downward", and a direction from the brushless motor <NUM> toward the electronic substrate <NUM> (a direction from the output side of the brushless motor <NUM> toward the opposite side to the output side of the brushless motor <NUM>) in the axial direction X is referred to as "upward direction" or simply "upward".

The stator <NUM> includes a housing (motor case) <NUM> also serving as a yoke, a plurality of stator cores (core members) <NUM> fixed to an inner peripheral side of the housing <NUM>, and the plurality of coils <NUM> each wound around the plurality of stator cores <NUM>. The housing <NUM> is made of metal such as iron and has a bottomed cylindrical shape. A holder unit <NUM> (described later) made of, for example, synthetic resin is attached to an opening of the housing <NUM>. The electronic substrate <NUM> is attached to an upper portion of the holder unit <NUM>, and an upper portion of the electronic substrate <NUM> is covered with a top cover <NUM>. The housing <NUM>, the holder unit <NUM>, and the top cover <NUM> are fixed by screws <NUM>. Each coil <NUM> is formed by winding a conductive metal wire such as copper around the stator core <NUM> a plurality of times.

The electronic substrate <NUM> includes a substrate body <NUM> arranged along a plane P intersecting the axial direction X on the opposite side to the output side of the brushless motor <NUM>, and a terminal <NUM> fixed on a surface 32A of the substrate body <NUM> on the opposite side to the rotor <NUM>. In the illustrated exemplary embodiment, the plane P is orthogonal to the axial direction X. A through hole <NUM> penetrating in the axial direction X is formed in the substrate body <NUM>. Hereinafter, the surface 32A of the substrate body <NUM> opposite to the rotor <NUM> is referred to as the "upper surface 32A" of the substrate body <NUM>, and the surface of the substrate body <NUM> on the side of the rotor <NUM> is referred to as the "lower surface 32B" of the substrate body <NUM>.

The substrate body <NUM> is a so-called printed circuit board (PCB), and is a printed-circuit board configured by mounting various electronic components on a printed wiring board (PWB) such as a glass epoxy substrate formed of a fiber-reinforced resin obtained by hardening cloth woven using glass fibers or the like with an epoxy resin. The printed wiring board may be, for example, a composite substrate in which paper and a glass substrate are mixed, a flexible substrate, or a ceramic substrate.

The through hole <NUM> is formed from the lower surface 32B to the upper surface 32A of the substrate body <NUM>. The cross-sectional shape of the through hole <NUM> orthogonal to the axial direction X is formed, for example, in a circular shape.

The terminal <NUM> is a conductive member formed of a metal such as copper, and is connected to a coil wire <NUM> to electrically connect the electronic substrate <NUM> and the coil <NUM>. The coil wire <NUM> of the coil <NUM> is inserted into the through hole <NUM>, and is welded to the terminal <NUM> by fusing on the opposite side of the rotor <NUM> with the substrate body <NUM> interposed therebetween.

Here, an on-vehicle electric oil pump to which the on-vehicle brushless motor device <NUM> is applied may be disposed adjacent to a drive shaft or the like in the axial direction X. Therefore, if the on-vehicle brushless motor device <NUM> can be downsized in the axial direction X, it is possible to avoid interference with a movable portion such as a drive shaft, and the degree of freedom of design is improved.

In this regard, according to the configuration of the present disclosure described above, the coil wire <NUM> of the coil <NUM> is directly welded to the terminal <NUM> on the side opposite to the rotor <NUM> with the substrate body <NUM> interposed therebetween. Therefore, the distance between the electronic substrate <NUM> and the winding portion of the coil <NUM> can be reduced as compared with the case where the coil and the electronic substrate are connected to each other via a component such as a rigid terminal pin disposed between the electronic substrate and the coil, for example, and it is possible to provide the on-vehicle brushless motor device <NUM> that can be downsized in the axial direction X. In addition, the number of welding points can be reduced as compared with the case where the coil and the electronic substrate are connected to each other via a terminal pin. Therefore, it is possible to provide the on-vehicle brushless motor device <NUM> with improved assemblability.

In some embodiments, for example, as illustrated in <FIG> and <FIG>, the on-vehicle brushless motor device <NUM> described above may further include the holder unit <NUM> including a connector terminal <NUM> for connecting the substrate body <NUM> and an external device (not illustrated), and a holder <NUM> disposed between the electronic substrate <NUM> and the brushless motor <NUM> to support the electronic substrate <NUM>.

The holder <NUM> functions as a partition member that partitions a space in which the brushless motor <NUM> is disposed and a space in which the electronic substrate <NUM> is disposed, and also functions as a support portion that rotatably supports the output shaft <NUM> of the brushless motor <NUM> via a bearing (not illustrated). The holder <NUM> is made of resin, and for example, may be formed by insert molding. For example, as illustrated in <FIG>, the holder <NUM> includes a groove portion <NUM> formed along the outer circumference of the holder <NUM> in the peripheral edge portion on the upper surface side. By filling the adhesive in the groove portion <NUM>, it is possible to ensure airtightness between the space in which the electronic substrate <NUM> is disposed and the outside of the on-vehicle brushless motor device <NUM>.

The connector terminal <NUM> is formed integrally with the holder <NUM> by embedding a part of the connector terminal <NUM> in the holder <NUM>. For example, the holder unit <NUM> is formed by insert-molding the holder <NUM> with a part of the connector terminal <NUM> embedded therein. One end 58A of the connector terminal <NUM> is provided to protrude upward from the upper surface of the holder <NUM>, and is connected to the electronic substrate <NUM> disposed above by soldering, for example. The other end 58B of the connector terminal <NUM> is provided in a state of projecting, for example, in the horizontal direction from the peripheral edge portion of the holder <NUM>. The connector terminal <NUM> is a conductive member formed of a metal such as copper, for example, and the other end 58B thereof is connected to an external device (not illustrated), thereby electrically connecting the electronic substrate <NUM> and the external device. Note that the other end 58B of the connector terminal <NUM> may be provided to protrude upward or downward from the peripheral edge portion of the holder <NUM>, for example, in accordance with the relative arrangement with the external device to be connected.

For example, a third soldering portion <NUM> may be provided to connect the one end 58A of the connector terminal <NUM> provided to protrude upward from the upper surface 32A of the substrate body <NUM> through the through hole <NUM> penetrating the substrate body <NUM> in the axial direction X and a metal foil terminal portion <NUM> provided on the upper surface 32A of the substrate body <NUM>.

According to the on-vehicle brushless motor device <NUM>, since the holder unit <NUM> in which the holder <NUM> and the connector terminal <NUM> are integrally formed is provided between the electronic substrate <NUM> and the brushless motor <NUM>, it is possible to provide the on-vehicle brushless motor device <NUM> in which the electronic substrate <NUM> and the external device can be easily connected to each other while the electronic substrate <NUM> arranged on the opposite side of the rotor <NUM> with the holder unit <NUM> interposed therebetween is supported by the holder <NUM> and which is easy to be assembled. Further, according to the configuration of connecting the connector terminal <NUM> and a metal foil terminal portion <NUM> via the third soldering portion <NUM>, soldering can be performed from above the substrate body <NUM>. Therefore, it is possible to provide the on-vehicle brushless motor device <NUM> with improved assemblability.

In some embodiments, for example, as illustrated in <FIG> and <FIG>, in the configuration of including the holder unit <NUM> described above, the holder <NUM> may include a guide hole <NUM> for guiding the coil wire <NUM> from the brushless motor <NUM> side to the through hole <NUM> of the substrate body <NUM> as penetrating the holder <NUM> in the axial direction X.

The guide hole <NUM> is formed to penetrate the holder <NUM> in the axial direction X from the lower surface side to the upper surface side of the holder <NUM>. The cross-sectional shape of the guide hole <NUM> orthogonal to the axial direction X is formed, for example, in a circular shape. The guide hole <NUM> is formed such that a substrate-side opening end <NUM>, which is an opening end of the guide hole <NUM> on the electronic substrate <NUM> side (upper side), overlaps the through hole <NUM> as viewed in the axial direction X (more specifically, such that the substrate-side opening end <NUM> is accommodated inside the through hole <NUM> as viewed in the axial direction X).

According to the on-vehicle brushless motor device <NUM>, since the holder <NUM> includes the guide hole <NUM>, the coil wire <NUM> can be guided upward from the brushless motor <NUM> side (lower side) of the holder <NUM>, and further, the coil wire <NUM> can be guided to the through hole <NUM> of the electronic substrate <NUM>. Therefore, for example, one end of the coil wire <NUM>, which is relatively flexible and has an indefinite shape compared to a rigid member such as a terminal pin, can be smoothly guided to the through hole <NUM> of the electronic substrate <NUM>. Therefore, it is possible to provide the on-vehicle brushless motor device <NUM> with improved assemblability. By removing the insulating film of the coil wire <NUM> of the coil <NUM> in advance, soldering is facilitated.

<FIG> are views illustrating configuration examples of the terminal <NUM> according to an embodiment. <FIG> is a top view (viewed in the axial direction X) of the terminal <NUM>, <FIG> is a side view of the terminal <NUM>, and <FIG> is a bottom view (viewed in the axial direction X) of the terminal <NUM>. <FIG> illustrate the terminal <NUM> in a state before the fusion welding of the terminal <NUM> and the coil wire <NUM> is performed.

According to the invention, as illustrated in <FIG>, in the configuration described above, a first slit <NUM> extending along a first direction a1 included in the plane P is formed in the terminal <NUM>. The terminal <NUM> includes a first terminal portion <NUM> provided on one side and a second terminal portion <NUM> provided on the other side with the first slit <NUM> interposed therebetween, a third terminal portion <NUM> connecting the first terminal portion <NUM> and the second terminal portion <NUM>, and a protruding portion <NUM> provided to protrude from the second terminal portion <NUM> to the opposite side to the rotor <NUM> in the axial direction.

The first terminal portion <NUM>, the second terminal portion <NUM>, and the third terminal portion <NUM> are formed on a flat plate as a whole and constitute a base portion <NUM> of the terminal <NUM>. The base portion <NUM> may be a flat plate-shaped member having, for example, a J-shape, a U-shape, or a V-shape as viewed in the axial direction X, and is disposed parallel to the plane P to face the upper surface 32A of the substrate body <NUM>.

The protruding portion <NUM> is fusion-welded to the coil wire <NUM>. The first terminal portion <NUM> is connected to the substrate body <NUM> via a first soldering portion <NUM>. In this specification, the term "soldering portion" means a solder located between a plurality of members (for example, <NUM> members) when the members are connected by soldering.

The melting point temperature of a typical lead-free solder is known to be, for example, about <NUM>. On the other hand, for example, in fusion welding in which copper is melted, a temperature of about <NUM> being the melting point of copper or higher is generated, and there is a concern that the soldering portion may be melted again (remelted) by the heat and the terminal may fall off from the electronic substrate.

According to the on-vehicle brushless motor device <NUM>, the distance along the surface of the terminal <NUM> from the protruding portion <NUM> to the first soldering portion <NUM> (the length along the arrow K in <FIG>) can be increased while suppressing an increase in the size of the terminal <NUM>. Therefore, it is possible to suppress the heat of welding from being transmitted from the protruding portion <NUM> to the first soldering portion <NUM> at the time of fusion welding of the protruding portion <NUM> and the coil wire <NUM>, and to suppress remelting of the first soldering portion <NUM>. Therefore, it is possible to realize an excellent electrical connection state between the electronic substrate <NUM> and the coil <NUM> while suppressing an increase in size of the on-vehicle brushless motor device <NUM>.

In some embodiments, for example, as illustrated in <FIG>, the second terminal portion <NUM> includes a second soldering portion <NUM> soldered to the substrate body <NUM>. The first soldering portion <NUM> and the second soldering portion <NUM> are separated from each other. The first soldering portion <NUM> and the second soldering portion <NUM> are arranged to extend in parallel with each other with the first slit <NUM> interposed therebetween.

According to this configuration, the coil <NUM> and the electronic substrate <NUM> can be electrically connected to each other via the first soldering portion <NUM> and the second soldering portion <NUM>. Further, since the first soldering portion <NUM> and the second soldering portion <NUM> are separated from each other, even if the second soldering portion <NUM> is remelted by the heat of welding of the protruding portion <NUM> and the coil wire <NUM>, the remelting of the first soldering portion <NUM> can be suppressed. Accordingly, an excellent electrical connection state between the electronic substrate <NUM> and the coil <NUM> can be realized.

In some embodiments, for example, as illustrated in <FIG>, the third terminal portion <NUM> is connected to one end portion 44a of the second terminal portion <NUM> in the first direction a1 and the protruding portion <NUM> is connected to the other end portion 44b of the second terminal portion <NUM> in the first direction a1.

According to this configuration, the distance along the surface of the terminal <NUM> from the protruding portion <NUM> to the third terminal portion <NUM> can be increased. Therefore, the distance along the surface of the terminal <NUM> from the protruding portion <NUM> to the first soldering portion <NUM> can be increased while suppressing an increase in the size of the terminal <NUM>. Therefore, it is possible to effectively suppress the heat of welding from being transmitted from the protruding portion <NUM> to the first soldering portion <NUM> at the time of fusion welding of the protruding portion <NUM> and the coil wire <NUM>, and to suppress remelting of the first soldering portion <NUM>.

In some embodiments, for example, as illustrated in <FIG> and <FIG>, the protruding portion <NUM> includes a base end portion 80a connected to the other end portion 44b of the second terminal portion <NUM> and a hook portion 80b formed in a hook shape and engaged with the coil wire <NUM>. In the illustrated exemplary embodiment, the base end portion 80a is formed in a flat plate shape along a plane intersecting the arrow a1 (a plane orthogonal to the arrow a1 in the illustrated embodiment). The hook portion 80b extends from the base end portion 80a and is formed in a curved or bent plate shape. The hook portion 80b may be bent such that the distal end thereof is folded back toward the second terminal portion <NUM> side to surround the coil wire <NUM> protruding from the upper surface 32A of the substrate body <NUM>. In the terminal <NUM> configured as described above, the base portion <NUM> and the protruding portion <NUM> may be integrally formed of the same member.

According to the on-vehicle brushless motor device <NUM> having such a configuration, it is possible to secure a long distance from the hook portion 80b disposed at the distal end of the protruding portion <NUM> and fusion-welded to the coil wire <NUM> to the first terminal portion <NUM> via the base end portion 80a of the protruding portion <NUM>, the second terminal portion <NUM>, and the third terminal portion <NUM>. Therefore, it is possible to suppress heat generated when the hook portion 80b and the coil wire <NUM> are welded from being transmitted to the first soldering portion <NUM>.

<FIG> is a plan view schematically illustrating a configuration example of the terminal <NUM> illustrated in <FIG>.

In some embodiments, for example, as illustrated in <FIG>, in the configuration that the terminal <NUM> includes the first terminal portion <NUM> and the second terminal portion <NUM>, the length L2 of the second terminal portion <NUM> in the first direction a1 may be longer than the length L1 of the first terminal portion <NUM> in the first direction a1.

According to the on-vehicle brushless motor device <NUM> having such a configuration, since the distance along the surface of the terminal <NUM> from the protruding portion <NUM> to the first soldering portion <NUM> can be increased, it is possible to suppress the first soldering portion <NUM> from being remelted by the heat of welding of the protruding portion <NUM> and the coil wire <NUM>.

<FIG> is a perspective view schematically illustrating the metal foil terminal portion <NUM> in an embodiment. <FIG> is a perspective view schematically illustrating a first opening <NUM> and a second opening <NUM> of a resist <NUM> in an embodiment. <FIG> is a perspective view schematically illustrating a state in which the terminal <NUM> is mounted on the substrate body <NUM> in an embodiment. <FIG> is a plan view schematically illustrating a configuration example of the metal foil terminal portion <NUM> in an embodiment.

In some embodiments, in the configuration including the first soldering portion <NUM> and the second soldering portion <NUM>, for example, as illustrated in <FIG>, the electronic substrate <NUM> may include the metal foil terminal portion <NUM> adjacent to the through hole <NUM> and disposed along the surface 32A of the substrate body <NUM> opposite to the rotor <NUM>, and the resist <NUM> disposed on the metal foil terminal portion <NUM> and having the first opening <NUM> corresponding to the first soldering portion <NUM> and a second opening <NUM> corresponding to the second soldering portion <NUM>.

For example, as illustrated in <FIG>, a second slit <NUM> extending along the first direction a1 is formed in the metal foil terminal portion <NUM>. That is, the slit <NUM> and the slit <NUM> extend along the same direction. The metal foil terminal portion <NUM> includes a first portion <NUM>, a second portion <NUM>, and a third portion <NUM>. As illustrated in <FIG> and <FIG>, the first portion <NUM> is provided on one side and the second portion <NUM> is provided on the other side with the second slit <NUM> having one end opened interposed therebetween. The first portion <NUM> is connected to the first soldering portion <NUM> (see <FIG>) in the first opening <NUM>. Thus, the first portion <NUM> is connected to the first terminal portion <NUM> via the first soldering portion <NUM> located in the first opening <NUM>. The second portion <NUM> is connected to the second soldering portion <NUM> (see <FIG>) in the second opening <NUM>. Thus, the second portion <NUM> is connected to the second terminal portion <NUM> via the second soldering portion <NUM> located in the second opening <NUM>.

The metal foil terminal portion <NUM> may be a flat plate-shaped member having, for example, a J-shape, a U-shape, or a V-shape as viewed in the axial direction X, and is disposed parallel to the plane P to face the upper surface 32A of the substrate body <NUM>.

The second portion <NUM> functions as a heat sink that dissipates heat generated during welding of the hook portion 80b and the coil wire <NUM>. The first portion <NUM> and the second portion <NUM> may be disposed to extend in parallel to each other with the second slit <NUM> interposed therebetween.

According to the on-vehicle brushless motor device <NUM> having such a configuration, in the transmission path of heat generated by welding of the hook portion 80b and the coil wire <NUM>, most of the heat can be radiated in the second portion <NUM> before the first soldering portion <NUM>. Therefore, even if the second soldering portion <NUM> is remelted by the heat generated by welding of the hook portion 80b and the coil wire <NUM>, the electrical connection between the electronic substrate <NUM> (more specifically, the metal foil terminal portion <NUM>) and the coil <NUM> can be ensured at least via the first soldering portion <NUM>. Therefore, an excellent electrical connection state between the electronic substrate <NUM> and the coil <NUM> can be realized.

In some embodiments, for example, as illustrated in <FIG>, the area A2 of the second portion <NUM> may be larger than the area A1 of the first portion <NUM>. In this case, the area A2 of the second portion <NUM> may be <NUM> times or more the area A1 of the first portion <NUM>. More preferably, the area A2 of the second portion <NUM> may be <NUM> times or more the area A1 of the first portion <NUM>.

According to the on-vehicle brushless motor device <NUM> having such a configuration, in the transmission path of the heat generated by welding of the hook portion 80b and the coil wire <NUM>, most of the heat can be radiated in the second portion <NUM> having the area A2 larger than that of the first portion <NUM> or having the area A2 equal to or larger than <NUM> times that of the first portion <NUM> before the first terminal portion <NUM> to the first soldering portion <NUM>. Thus, even if the second soldering portion <NUM> is remelted by the heat of welding of the protruding portion <NUM> and the coil wire <NUM>, the remelting of the first soldering portion <NUM> can be suppressed. Therefore, the electrical connection between the electronic substrate <NUM> (more specifically, the metal foil terminal portion <NUM>) and the coil <NUM> can be more reliably ensured via at least the first soldering portion <NUM>. Accordingly, it is possible to efficiently suppress a decrease in yield of the on-vehicle brushless motor device <NUM>.

In some embodiments, for example, as illustrated in <FIG>, in any one of the configurations described above, the electronic substrate <NUM> may include a plurality of terminals <NUM>. The terminals <NUM> may be configured to be oriented in the same direction with respect to the substrate body <NUM>.

Specifically, for example, the electronic substrate <NUM> may be configured such that the directions of the first terminal portion <NUM>, the second terminal portion <NUM>, the protruding portion <NUM>, and the hook portion 80b with respect to the substrate body <NUM> are unified in the respective terminals <NUM>.

According to the on-vehicle brushless motor device <NUM> having such a configuration, each terminal <NUM> can be automatically mounted on the substrate body <NUM> by using, for example, a mounter device (automatic assembly device) (not illustrated). Further, since the orientation of the mounter device or the substrate body <NUM> does not needs to be changed when each terminal <NUM> is mounted, the time required for assembling can be shortened. Accordingly, it is possible to provide an on-vehicle brushless motor with improved assemblability. Further, the on-vehicle brushless motor device <NUM> can be assembled at low cost.

<FIG> is a plan view schematically illustrating a region above the electronic substrate <NUM> in an embodiment. <FIG> is a side view schematically illustrating a region above the electronic substrate <NUM> in an embodiment.

According to the above-described on-vehicle brushless motor device <NUM> of the present disclosure, for example, as illustrated in <FIG> and <FIG>, a tool area <NUM> for an electrode of a fusing device for performing fusion welding is secured above the electronic substrate <NUM>. Therefore, it is possible to suppress the interference between the parts arranged around the terminal <NUM> and the electrode of the fusing device, and to improve the assemblability of the on-vehicle brushless motor device <NUM>.

<FIG> is a side sectional view illustrating a configuration example of the guide hole <NUM> in an embodiment. <FIG> is a side sectional view illustrating a modification of the guide hole <NUM> in an embodiment.

In some embodiments, for example, as illustrated in <FIG>, <FIG>, in the on-vehicle brushless motor device <NUM> in which the holder <NUM> includes the guide hole <NUM>, the guide hole <NUM> may include a tapered passage portion <NUM> formed to be tapered such that the hole diameter (passage diameter) decreases as a distance from the rotor <NUM> increases in the axial direction X.

Thus, the one end of the coil wire <NUM> can be smoothly guided to the through hole <NUM> of the electronic substrate <NUM> via the tapered passage portion <NUM>. Therefore, it is possible to provide the on-vehicle brushless motor device <NUM> with improved assemblability. For example, the holder unit <NUM> on which the electronic substrate <NUM> is mounted in advance and the coil <NUM> can be assembled by an automatic assembling apparatus. Subsequently, by performing fusion welding of the hook portion 80b and the coil wire <NUM>, the electronic substrate <NUM> and the coil <NUM> can be electrically connected to each other.

A motor-side opening end <NUM>, which is an opening end of the guide hole <NUM> on the brushless motor <NUM> side, has a diameter sufficiently larger than the diameter of the coil wire <NUM>. Specifically, as illustrated in <FIG>, the motor-side opening end <NUM> may be configured to satisfy <NUM>≤d2/d1, where d1 is the diameter of the coil wire <NUM> and d2 is the diameter of the motor side opening end <NUM> (the inner diameter of the motor-side opening end <NUM>). The "diameter of the motor-side opening end <NUM>" means the hole diameter (passage diameter) of the guide hole <NUM> at the position of the motor-side opening end <NUM>.

In some embodiments, for example, as illustrated in <FIG>, the guide hole <NUM> may include a substrate-side passage portion <NUM> having a passage diameter that is uniform in the axial direction. In the illustrated embodiment, the substrate-side passage portion <NUM> is configured to connect the substrate-side opening end <NUM> and the upper end of the tapered passage portion <NUM>.

As a result, when the coil wire <NUM> guided by the guide hole <NUM> passes through the substrate-side passage portion <NUM>, it is possible to give upward directivity to the coil wire <NUM>. Therefore, the coil wire <NUM> can be more easily and smoothly guided toward the through hole <NUM> of the electronic substrate <NUM>. In another embodiment, the guide hole <NUM> may have the tapered passage portion <NUM> extending from the motor-side opening end <NUM> to the substrate-side opening end <NUM>. That is, the lower end of the tapered passage portion <NUM> may be the motor-side opening end <NUM>, and the upper end of the tapered passage portion <NUM> may be the substrate-side opening end <NUM>.

In some embodiments, for example, as illustrated in <FIG>, the holder <NUM> may include a cylindrical portion <NUM> protruding toward the opposite side of the rotor <NUM>.

In this case, at least a part of the guide hole <NUM> is formed by the inner peripheral surface 82A of the cylindrical portion <NUM>. In this case, the substrate-side opening end <NUM>, which is the upper end of the inner peripheral surface 82A of the cylindrical portion <NUM>, may be disposed below the through hole <NUM> as illustrated in <FIG>, may be disposed inside the through hole <NUM>, may be arranged flush with the upper surface 32A of the electronic substrate <NUM> as illustrated in <FIG>, or may be disposed above the upper surface 32A of the electronic substrate <NUM>. Further, as illustrated in <FIG>, at least a part of a cylindrical substrate-side portion 82B of the cylindrical portion <NUM>, which forms the substrate-side passage portion <NUM> on the inner peripheral surface thereof, may be disposed inside the through hole <NUM>.

As illustrated in <FIG>, by disposing the substrate-side portion 82B of the cylindrical portion <NUM> inside the through hole <NUM>, the one end of the coil wire <NUM> can be smoothly guided by the through hole <NUM> of the electronic substrate <NUM>. Therefore, it is possible to provide the on-vehicle brushless motor device <NUM> with improved assemblability.

In some embodiments, for example, as illustrated in <FIG>, in the on-vehicle brushless motor device <NUM> in which the guide hole <NUM> includes the tapered passage portion <NUM>, the diameter D2 of the substrate-side opening end <NUM> (the inner diameter of the substrate-side opening end <NUM>) may be smaller than the diameter D1 of the through hole <NUM>. According to the on-vehicle brushless motor device <NUM> having the above-described structure, the coil wire <NUM> having passed through the substrate-side opening end <NUM> may be more easily and smoothly guided to the through hole <NUM> of the electronic substrate <NUM>. The "diameter of the substrate-side opening end <NUM>" means the hole diameter (passage diameter) of the guide hole <NUM> at the position of the substrate-side opening end <NUM>.

Next, a method of manufacturing an on-vehicle brushless motor device according to an embodiment of the present disclosure will be described. <FIG> is a flowchart illustrating a method of manufacturing an on-vehicle brushless motor device according to an embodiment. As shown in <FIG>, the method of manufacturing the on-vehicle brushless motor device <NUM> includes step S1 of arranging the substrate body <NUM> of the electronic substrate <NUM> along a plane P intersecting the axial direction X on the side opposite to the output side of the brushless motor <NUM>, step S2 of passing the coil wire <NUM> of the coil <NUM> constituting the stator <NUM> of the brushless motor <NUM> through the through hole <NUM> of the electronic substrate <NUM>, and step S3 of welding the coil wire <NUM> to the hook portion 80b of the terminal <NUM> fixed on the surface 32A of the substrate body <NUM> opposite to the rotor <NUM> with respect to the electronic substrate <NUM>.

In step S1, for example, the electronic substrate <NUM> on which various electronic components for controlling drive of the brushless motor <NUM> are mounted is disposed on the upper surface of the holder unit <NUM> that partitions the space in which the brushless motor <NUM> is disposed and the space in which the electronic substrate <NUM> is disposed. At this time, for example, the electronic substrate <NUM> may be disposed such that the through hole <NUM> formed in the electronic substrate <NUM> in advance for allowing the coil wire <NUM> to pass therethrough and the guide hole <NUM> formed in the holder unit <NUM> in advance to guide the coil wire <NUM> into the through hole <NUM> overlap each other when viewed in the axial direction X. Further, the third soldering portion <NUM> for connecting the one end 58A of the connector terminal <NUM> and the metal foil terminal portion <NUM> is formed.

As a pre-process of step S1, the metal foil terminal portion <NUM> is provided on the substrate body <NUM>, and the resist <NUM> is disposed on the metal foil terminal portion <NUM>. Then, the first portion <NUM> exposed inside the first opening <NUM> and the first terminal portion <NUM> are connected by soldering to form the first soldering portion <NUM>. Further, the second portion <NUM> exposed inside the second opening <NUM> and the second terminal portion <NUM> are connected by soldering to form the second soldering portion <NUM>.

In step S2, for example, the one end of the coil wire <NUM> is passed through the through hole <NUM> by guiding the coil wire <NUM> along the tapered passage portion <NUM> that is formed in advance in the holder <NUM> of the holder unit <NUM>, as the guide hole <NUM>, so that the diameter of thereof decreases from the lower surface side toward the upper surface side of the holder <NUM>.

In step S3, for example, one end of the coil wire <NUM> protruding to the upper side of the electronic substrate <NUM> through the through hole <NUM> is disposed so that the one end faces upward, and the coil wire <NUM> and the terminal <NUM> are fusion-welded so that the coil wire <NUM> is disposed inside the hook portion 80b. Further, the metal foil terminal portion <NUM> is provided on the substrate body <NUM>, and the resist <NUM> is arranged on the metal foil terminal portion <NUM>. The first soldering portion <NUM> is soldered to the first portion <NUM> exposed inside the first opening <NUM>. The second soldering portion <NUM> is soldered to the second portion <NUM> exposed inside the second opening <NUM>.

According to the method of manufacturing the on-vehicle brushless motor device <NUM>, as described above, the coil wire <NUM> of the coil <NUM> passes through the through hole <NUM> of the substrate body <NUM> and is directly fusion-welded to the terminal <NUM> on the side opposite to the rotor <NUM>. Therefore, it is possible to provide the on-vehicle brushless motor device <NUM> that can be downsized in the axial direction X compared to a case where the coil <NUM> and the electronic substrate <NUM> are connected to each other via a rigid component such as a terminal pin. Further, the number of welding points can be reduced as compared with the case where the coil <NUM> and the electronic substrate <NUM> are connected to each other via the terminal pin. Therefore, the on-vehicle brushless motor device <NUM> can be easily manufactured.

The present invention is not limited to the above-described embodiments, but rather defined by the appended claims, and includes modifications of the above-described embodiments and combinations of these embodiments.

Claim 1:
An on-vehicle brushless motor device (<NUM>), comprising:
a brushless motor (<NUM>) including a rotor (<NUM>) and a stator (<NUM>) which include a plurality of coils (<NUM>) arranged around the rotor (<NUM>); and
an electronic substrate (<NUM>) including a substrate body (<NUM>) provided with a through hole (<NUM>) penetrating in the axial direction of the rotor (<NUM>) and arranged along a plane intersecting the axial direction on the side opposite to the output side of the brushless motor (<NUM>),
wherein the electronic substrate (<NUM>) includes a terminal (<NUM>) fixed on a surface of the substrate body (<NUM>) opposite to the rotor (<NUM>), and a coil wire (<NUM>) of the coil (<NUM>) is inserted through the through hole (<NUM>) and welded to the terminal (<NUM>) on a side opposite to the rotor (<NUM>) with respect to the substrate body (<NUM>)
characterized in that a first slit (<NUM>) extending along a first direction included in the plane is formed in the terminal (<NUM>),
the terminal (<NUM>) includes a first terminal portion (<NUM>) provided on one side and a second terminal portion (<NUM>) provided on the other side with the first slit (<NUM>) interposed therebetween, a third terminal portion (<NUM>) connecting the first terminal portion (<NUM>) and the second terminal portion (<NUM>), and a protruding portion (<NUM>) provided to protrude from the second terminal portion (<NUM>) to the opposite side to the rotor (<NUM>) in the axial direction,
the protruding portion (<NUM>) is welded to the coil wire (<NUM>), and
the first terminal portion (<NUM>) is connected to the substrate body (<NUM>) via a first soldering portion (<NUM>).