JP4404199B2

JP4404199B2 - Synchronous motor

Info

Publication number: JP4404199B2
Application number: JP2004100155A
Authority: JP
Inventors: 弘治吉浪; 康夫浅井; 康博行竹; 隆敏阪田
Original assignee: 株式会社ジェイテクト
Priority date: 2004-03-30
Filing date: 2004-03-30
Publication date: 2010-01-27
Anticipated expiration: 2024-03-30
Also published as: JP2005287240A

Description

The present invention relates to a synchronous motor in which a coil is directly wound around a stator core via a resin insulator. More specifically, the synchronous motor is less susceptible to external forces such as vibration and is compact and reliable for mounting on a vehicle or the like. Related to high three-phase brushless synchronous motor.

In a synchronous motor (synchronous motor) such as a brushless motor, a rotor (rotor) having a magnet for forming a magnetic field rotates inside or outside a stator (stator) having a coil. This stator includes a stator core (stator core) having teeth (magnetic pole teeth or salient poles) and slots (iron core grooves) formed between the teeth, coils (windings) arranged around the teeth, and these It is formed mainly of an insulator disposed between the stator core and the coil.

As a method of attaching a coil to a stator core, there are a concentrated winding method in which a coil is directly wound around a tooth portion of the stator core via an insulator, and a distributed winding method in which a separately wound coil is fitted into the stator core.

Among these methods, in a synchronous motor that employs a concentrated winding method, as a means for connecting a connecting wire (crossover wire) between coils and a lead wire (lead wire) connected to a power source (or controller), conventionally, A method in which a resin bracket formed integrally with a connection plate connecting coils is arranged on one end side of the stator core (Patent Document 1), or a method using a printed circuit board in which a circuit connecting each coil is etched ( Patent document 2) etc. are used.

In addition, as a means for facilitating the connection work of these coils, a method using a plate-like connection member (bus bar) provided with a plurality of terminals for connection to the end portions of the coils has been proposed (for example, Patent Documents). 3 or Patent Document 4).

By the way, when a coil is directly wound around the teeth portion of the stator core, it is necessary to sandwich an insulator between them. Therefore, in order to simplify this work, in the inner rotor type brushless synchronous motor, a cylindrical stator core is used. Resin insulators for insulating the coil from the stator core are mounted at both ends in the axial direction (see, for example, Patent Document 5).

FIG. 7 is an exploded perspective view showing a configuration of a stator in a conventional brushless synchronous motor. This motor stator corresponds to a three-phase structure, and the six tooth portions 101t are paired with the tooth portions 101t arranged on the opposite sides in the circumferential direction, and are arranged in U phase, V phase and W phase. It corresponds. The stator core 101 is formed by laminating a large number of magnetic steel plates punched into a predetermined shape.

The insulators (102, 103) attached to the stator core 101 are arranged on the opposite side (rear side) to the front side insulator 102 inserted from the lead wire side (front side: upper side in the figure) connected to a power source or a controller (not shown). : A pair of assembled members composed of the rear insulator 103 inserted from below.

These insulators 102 and 103 are molded using a hard synthetic resin, and annular portions 102 a and 103 a disposed on the end surface of the stator core 101, and project from the annular portions 102 a and 103 a in the axial direction. The plurality of comb-like portions 102b and 103b are fitted into the slot 101s. Note that the comb-like portion 102b of the front-side insulator 102 and the comb-like portion 103b of the rear-side insulator 103 have their tips aligned with each other so as to cover all the inner surfaces of the slots 101s when inserted into the slots 101s of the stator core 101. It is configured to touch or overlap.

In addition, a conductive wire covered with enamel or the like is wound around each tooth portion 101t of the stator core 101 into which the insulators 102 and 103 are inserted, and coils corresponding to U, V, and W phases are formed. In addition, the winding start end and winding end end of each of these coils are connected.

In addition, regarding a stator of a synchronous motor using an insulator, as a means for fixing a lead wire (lead wire) connected to a power source and drawing it to a predetermined position, a method of bundling each lead wire with a fixed band (Patent Document 6) or an insulator A method (Patent Document 7) or the like of drawing around while engaging with a protrusion formed on the outer periphery of the outer periphery has been proposed. Further, in order to accommodate these lead wires, a flange (reference numeral 102c in FIG. 7) is formed on the front-side insulator.

JP-A-3-245760 JP-A-6-22484 Japanese Patent Laid-Open No. 6-233383 JP 2001-103700 A JP 2002-142418 A Japanese Patent Laid-Open No. 2000-60046 JP 2001-218407 A

By the way, the wiring method in the synchronous motor using the insulator as described above requires complicated and time-consuming wiring work according to each phase of U, V, and W, and requires a lot of space for wiring. It was an obstacle to downsizing.

Moreover, when these wiring methods are used for equipment mounted on a vehicle or the like, the wiring may be loosened by vibrations or heat, and there is a concern about troubles in long-term use.

The present invention has been made in order to address the above-described problems, and provides a compact and highly reliable synchronous motor that is simple in wiring work and that does not cause loosening of wiring due to external forces such as vibration. The purpose is to do.

In order to achieve the above-mentioned object, the invention according to claim 1 is characterized in that the synchronous motor includes a cylindrical stator core (11) in which a plurality of teeth and slots (11s) are formed radially inward. A coil (14) wound around the teeth portion, an annular portion along the end face shape of the stator core, and a comb-like portion fitted into the slot, and the stator core (11) from both axial ends. In a synchronous motor comprising a pair of resin insulators (12, 13) that are fitted to insulate between the stator core and the coils, and each coil is connected to a three-phase power source,
At least one of the pair of insulators (12, 13) is connected between a coil corresponding to each phase of three phases and a phase-specific wiring member (21, 22, 23) for connecting the power source, and between the coils of each phase. A common connection member (24) that is integrally formed with the annular portion in an electrically insulated state, and the phase-specific connection member and the common connection member have a coil connection terminal projecting radially from the annular portion of the insulator. a bus bar having protruding portions of the coil connection terminals, are bent in the axial direction, the portion where the coil connection terminals on the outer peripheral surface of the annular portion of the insulation regulator is protruding, of this site other are formed notch (12c) is smaller in diameter than the portion and is characterized by comprising.

In the synchronous motor in which the coil is directly wound around the stator core via the resin insulator, the present invention integrally molds a connecting member for connecting the coil and the power source and between the coils to the resin insulator. It is intended to achieve the intended purpose.

That is, according to the first aspect of the present invention, the insulator and the connecting member (wiring), which have been conventionally used as separate members, are integrally formed to reduce the space required for arranging these members. be able to. In addition, by reducing the space, the axial dimension of the stator and thus the entire synchronous motor can be shortened.

In addition, this configuration simplifies the wiring work according to each phase of U, V, and W, and there is no fear that the wiring is loosened due to vibration or heat, and the reliability of the synchronous motor can be improved. . Therefore, the synchronous motor of the present invention can be a compact and highly reliable synchronous motor.

Here, as a specific example of the phase-specific connection member and the common connection member, a bus bar having a coil connection terminal protruding in the radial direction from the annular portion of the insulator can be suitably employed.

When considering the molding method (insert molding, etc.) to the resin member and the structure of the mold to be used, the main body of the connection member needs to be strong enough to withstand the molding process, and the terminal protrudes from the insulator. The part needs a portion that is sandwiched between molds used for molding and stops the leakage of the resin. Accordingly, a bus bar made of a plate-like conductive member is suitable as the main body of the connecting member, and the coil connection terminal provided extending from the bus bar preferably has a shape protruding in the radial direction from the bus bar. With the above configuration, the manufacturing cost of the bus bar integrated insulator can be kept low without using a complicated manufacturing method or a mold.

The protruding portion of the coil connection terminal is bent in the axial direction, and this bending suppresses the amount of protrusion of the coil connection terminal in the radial direction, thereby preventing an increase in the radial dimension of the synchronous synchronous motor. it can.

In addition, it is desirable to form a notch having a smaller diameter in the outer peripheral surface of the annular portion of the insulator where the coil connection terminal protrudes and projects than in other portions.

By inserting a jig or the like into the notch, the coil connection terminal can be easily bent. In addition, this notch also has an effect of further reducing the amount of protrusion of the coil connection terminal in the radial direction, and when the bending is performed within this notch, the protrusion of the terminal in the radial direction is substantially zero. It is also possible.

Next, in the invention described in claim 2 , a part of the outer peripheral surface of the annular portion of the insulator (12, 13) protrudes in a radial direction from the outer peripheral surface, and the separate connection member (21, 22). , 23) is formed with a power connection terminal block (17) for integrally holding the power supply side end portions in an electrically insulated state.

In the present invention, the connection between the stator and the power source (or controller) is considered, and the end portions of the phase-specific connection members are collected at one place and molded on the outer periphery of the insulator. With this configuration, the coil and the power source can be easily connected without handling the lead wire.

It is preferable that the terminal block for power connection (17) is provided with a screw hole for each phase in which an end portion of the lead wire (18) connected to the power source can be screwed (Claim 3 ). ). Further, the power source connecting terminal block (17) is in the form its outermost diameter is equal to or less than the diameter of said stator core (11), and a shape stator core end surface thereof is in contact with the stator core is preferably (claim 4) .

These inventions are means for enhancing the durability of the connection portion with the power source, and are provided with a screw hole for each phase integrally with the power source side end portion of the phase-specific connecting member, thereby leading to the power source. The end of the wire can be firmly fixed by screwing. In addition, since the terminal block for power supply connection has a diameter equal to or smaller than the diameter of the stator core and is in close contact with the stator core, there is no fear of breakage when the screw is attached, and the occurrence of vibration or the like can be suppressed. Therefore, the synchronous motor according to the present invention does not cause the slack of wiring even by an external force such as vibration, and can be a highly reliable synchronous motor.

Further, in the synchronous motor in which the coil (14) is formed by one conductor for each phase,
The other of the pair of insulators (12, 13) is formed with a plurality of flanges (13c) protruding outward in the axial direction from the vicinity of the outer peripheral edge of the end surface of the annular portion, and on the outer peripheral surfaces of these flanges. Preferably, grooves or ribs for individually supporting the connecting wires (14a, 14b, 14c) between the coils in an electrically insulated state are formed (Claim 5).

With the above configuration, these connecting wires can be supported without interposing an insulator between the connecting wires provided between the coils of the same phase. Further, it is possible to prevent the connecting wires from contacting each other due to external forces such as vibration, and the reliability of the synchronous motor can be improved.

As described above, according to the present invention, a slack of wiring does not occur even by an external force such as vibration, and a highly reliable synchronous motor can be obtained. Further, by reducing the axial dimension, a small and lightweight synchronous motor can be obtained.

In addition, the number of parts is reduced, and the wiring work according to each phase of U, V, and W is simplified and simplified, so that the cost of the synchronous motor can be reduced.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing the structure of an electric pump unit using a synchronous motor according to the present invention, and FIG. 2 is an exploded perspective view of a motor stator used in the synchronous motor. 3 is a front view of a front-side insulator fitted to the motor stator, and FIG. 4 is a diagram showing individual shapes of bus bars molded on the front-side insulator. In the following description, the side of the motor stator where the lead wires are connected is referred to as the front side, and the opposite side in the axial direction is referred to as the rear side.

As shown in FIG. 1, the synchronous motor in the present embodiment is incorporated as a part of a motor-integrated hydraulic pump (trochoid gear pump) unit mounted in an automobile or the like. Inside the housing 1 of the electric pump unit, a motor chamber (motor unit 2) and a pump chamber (pump unit 3) are formed adjacent to each other. In addition, a main shaft 4 that is a drive shaft that is driven to rotate by the motor unit 2 and also a rotation shaft of the pump unit 3 is disposed in the housing, and is rotatably supported by bearings 5 and 6. .

The motor unit 2 includes a motor stator in which coils 14 (u, v, w) are wound around a plurality of teeth 11 t formed on a cylindrical stator core 11 via insulators 12, 13, and one end of a main shaft 4. A three-phase structure mainly composed of a motor rotor formed by adhering magnets 16 whose magnetization direction is a radial direction and whose direction is alternately opposite to the circumferential direction on the outer periphery of a rotor core 15 formed on the side. It is a brushless motor.

A front side insulator 12 and a rear side insulator 13, which will be described later, are fitted to the motor stator from both sides in the axial direction of the stator core 11, and a power source (illustrated) is connected to a power supply terminal block 17 provided on the front side insulator 12. Each lead wire 18 connected to (omitted) is fixed using a screw 19. The motor stator is fixedly arranged in a motor housing 1a having a substantially cylindrical shape with a bottom, and one end of the main shaft 4 is a rolling bearing 5 with respect to the motor housing 1a in a state where the motor rotor is inserted inside the motor stator. It is supported so that it can rotate freely.

The opening portion of the motor housing 1a is closed by the pump housing 1b, and the other end side of the main shaft 4 is rotatably supported by the pump housing 1b via a rolling bearing 6, After being sealed by the oil seal 7, it passes through the pump housing 1 b and faces the pump portion 3. The pump housing 1b is formed with a pump chamber that accommodates the inner gear 31 and the outer gear 32 of the trochoid pump, and the opening is closed by the pump plate 1c.

As shown in FIG. 2, six teeth portions 11t are formed on the stator core 11 used in the synchronous motor (motor portion 2) in the present embodiment, and these teeth are disposed on the opposite sides in the circumferential direction. It forms a pair with the part 11t and corresponds to each of the U phase, V phase and W phase. Further, the insulators 12 and 13 attached to the stator core 11 are from the front side insulator 12 inserted from the lead wire 18 side (upper side in the drawing) connected to the power source or the controller (not shown) and from the axially opposite side (lower side in the drawing). It is comprised as a pair of assembled member which consists of the rear side insulator 13 inserted.

These insulators 12 and 13 are molded using a hard synthetic resin such as polyphenylene sulfide (PPS), and annular portions 12a and 13a disposed on the end face of the stator core 11 and the annular portions 12a and 13a. Is formed from a plurality of comb-like portions 12b and 13b that are fitted in the slots 11s of the stator core 11. The comb-shaped portion 12b of the front-side insulator 12 and the comb-shaped portion 13b of the rear-side insulator 13 are overlapped with each other so as to cover all the inner surfaces of the slots 11s when inserted into the slots 11s of the stator core 11. It is configured.

As shown in the front view of FIG. 3, the front-side insulator 12 used in the synchronous motor of this embodiment is characterized in that the annular terminal portion 12a has coil terminal portions Bu and Bv that connect each coil and the power source. , Bw, respectively, as bus members 21, 22, 23 as phase connection members, and bus bar 24, as a common connection member including coil terminal portions Cu, Cv, Cw for connecting the coils of each phase, in an electrically insulated state It is the point which is integrally molded by. On the outer peripheral surface of the annular portion 12a, the portions where the terminal portions (Bu, Bw, Cu, Cv, Cw) protrude are notches 12c, 12c,... That have a smaller diameter than the other portions. Is formed.

The power connection terminal block 17 integrally formed on the outer periphery of the front insulator 12 has a shape in which the outermost diameter is equal to or smaller than the diameter of the stator core 11 and is in close contact with the stator core 11. In addition, screw holes are provided in the power connection terminal portions Tu, Tv, Tw corresponding to the respective phases.

Various methods can be considered as a method of forming the insulator 12 as described above. For example, in the state where these bus bars 21, 22, 23, and 24 are arranged apart from each other in the circumferential direction as shown in FIG. By performing insert molding, it is possible to integrate with the insulator 12 while maintaining an insulating state.

In addition, although each terminal part Bu, Bw, Cu, Cv, and Cw immediately after insert molding protrudes greatly from the outer peripheral surface of the insulator 12 similarly to FIG. 4, it is provided at the root of each terminal part. By inserting a jig or the like (not shown) into the holes 21a, 23a and 24a, 24b, 24c in the notch 12c, and bending the tips of these terminal portions in the axial direction (front side), as shown in FIG. It can be set as the shape by which the radial direction protrusion amount from 12a outer peripheral surface was suppressed.

As described above, by integrally molding the insulator and the connection member that were conventionally provided separately, the connection between the coil and the power source becomes easy, and the space necessary for the arrangement of the connection member is reduced. The axial dimension of the entire synchronous motor can be shortened.

Further, the notch 12c provided on the outer peripheral surface of the annular portion 12a suppresses the amount of protrusion of the terminal portion in the radial direction, thereby suppressing the radial dimension of the synchronous motor.

Furthermore, the power connection terminal block 17 can securely fix the lead wire 18 through the screw holes of the respective terminal portions Tu, Tv, Tw, and the shape thereof is equal to or less than the diameter of the stator core 11, and By adopting a shape that closely contacts the stator core 11, the stator core 11 has an effect of reinforcing the terminal block 17. Therefore, even when the lead wire 18 is fixed to the power supply terminal block 17 with the screw 19, there is no fear of the terminal block 17 being damaged, and the occurrence of vibration after fixing can be suppressed.

Next, a method for connecting the coils will be described.
FIG. 5 is a view of the motor stator before being assembled into the motor housing 1a as seen from the front side, and FIG. 6 is a view of the same motor stator as seen from the rear side.

Each coil 14 is formed by winding a conductive wire covered with an insulating material such as enamel around one tooth portion 11t of the stator core 11 in which the insulators 12 and 13 are fitted, and is opposed to the circumferential direction. In-phase coils (for example, 14u and 14u ′) are formed of a single conductor. Therefore, on the rear insulator 13 side, as shown in FIG. 6, conductive wires (crossover wires 14a, 14b, and 14c) that connect the coils in the same phase are formed over a half circumference for each phase.

As shown in FIG. 5, the winding start end portion and winding end end portion of the conducting wire are sandwiched between tips of coil terminal portions (for example, Bu and Cu) disposed on the opposite sides in the circumferential direction. Thus, it is connected to each terminal block by a fusing process in which the insulating coating on the surface is melted and integrated.

The rear insulator 13 used in the synchronous motor of this embodiment is characterized in that a plurality of flanges 13c projecting outward in the axial direction from the vicinity of the outer peripheral edge are formed on the end surface of the annular portion 13a. A rib 13d is provided on the outer peripheral surface of the flange 13c to support the connecting wires 14a, 14b, 14c between the coils in an electrically insulated state.

These ribs 13d can support these connecting wires without interposing an insulator between the connecting wires provided between the coils 14 having the same phase. These ribs 13d prevent the connecting wires from contacting each other due to external forces such as vibration.

Therefore, the synchronous motor according to the present embodiment, combined with the structure of the front insulator 12 described above, does not cause loosening of wiring due to external force such as vibration, and can be a compact and highly reliable synchronous motor. it can.

In the above embodiment, an example of the rib 13d protruding from the flange 13c of the rear insulator 13 is shown as the support structure for the crossover wires (14a, 14b, 14c), but this rib shape is particularly limited. Any shape can be used as long as it can support each crossover wire in an electrically insulated state. Further, the same effect can be obtained by forming a groove on the outer peripheral surface of the flange instead of the rib.

It is sectional drawing which shows the structure of the electric pump unit which uses the synchronous motor concerning this invention. It is a disassembled perspective view of the motor stator used for the synchronous motor in embodiment of this invention. It is a front view of the front side insulator fitted by the motor stator of the synchronous motor in the embodiment of the present invention. It is a figure which shows each shape of the bus-bar molded by the front side insulator of the synchronous motor in embodiment of this invention. It is the figure which looked at the motor stator of the synchronous motor in the embodiment of the present invention from the front side. It is the figure which looked at the motor stator of the synchronous motor in embodiment of this invention from the rear side. It is a disassembled perspective view of the motor stator used for the conventional synchronous motor.

DESCRIPTION OF SYMBOLS 1 Housing 1a Motor housing 1b Pump housing 1c Pump plate 2 Motor part 3 Pump part 4 Spindle 5, 6 Rolling bearing 7 Oil seal 11 Stator core 11s Slot 11t Teeth part 12 Front side insulator 12a Annular part 12b Comb part 12c Notch 13 Rear Side insulator 13a Annular portion 13b Comb portion 13c Flange 13d Rib 14 Coil 14a, 14b, 14c Crossover 15 Rotor core 16 Magnet 17 Power supply terminal block 18 Lead wire (lead wire)
19 Screws 21, 22, and 23 Busbar (phase-specific connection member)
21a, 23a hole 24 bus bar (common connection member)
24a, 24b, 24c Hole 31 Inner gear 32 Outer gear 101 Stator core 102 Front side insulator 103 Rear side insulator 14u, 14u ', 14v, 14v', 14w, 14w '(each phase) Coil Bu, Bv, Bw (By phase) Coil terminal Cu, Cv, Cw (shared) coil terminal Tu, Tv, Tw Power connection terminal

Claims

A cylindrical stator core having a plurality of teeth and slots formed radially inward, a coil wound around the teeth, an annular portion along the end face shape of the stator core, and the slot are fitted. And a pair of resin insulators that are fitted into the stator core from both ends in the axial direction to insulate the stator core and the coil, and the coils are connected to a three-phase power source. In the synchronous motor
At least one of the pair of insulators includes a coil corresponding to each phase of three phases, a phase-specific wiring member that connects the power source, and a common wiring member that connects between the coils of each phase in an electrically insulated state. The bus connection bar is formed integrally with the annular portion, and the separate connection member and the common connection member have a coil connection terminal protruding in a radial direction from the annular portion of the insulator, and the protruding portion of the coil connection terminal is A portion that is bent in the axial direction and that protrudes from the coil connection terminal on the outer peripheral surface of the annular portion of the insulator is formed with a notch that has a smaller diameter than the other portions. Synchronous motor characterized by
A terminal block for power connection that projects radially from the outer peripheral surface of a part of the outer peripheral surface of the annular portion of the insulator and that integrally holds the power source side end portions of the phase-specific connection members in an electrically insulated state. The synchronous motor according to claim 1, wherein the synchronous motor is formed.
3. The synchronous motor according to claim 2, wherein the terminal block for power connection is provided with a screw hole for each phase capable of screwing an end portion of a lead wire connected to the power source. 4.
The power supply connection terminal block is formed so that an outermost diameter thereof is equal to or smaller than a diameter of the stator core, and a stator core side end surface is formed in a shape in contact with the stator core. The synchronous motor according to claim 2 or claim 3.
In the synchronous motor in which the coil is formed by one conductor for each phase,
The other of the pair of insulators is formed with a plurality of flanges protruding outward in the axial direction from the vicinity of the outer peripheral edge of the end surface of the annular portion, and the flange between the coils is formed on the outer peripheral surface of these flanges. The synchronous motor according to any one of claims 2 to 4, wherein grooves or ribs for individually supporting the wires in an electrically insulated state are formed.