JPH0458751A - Brushless motor - Google Patents

Abstract

PURPOSE:To improve workability and reliability in the termination of coil by inserting the terminal of each coil into the insertion hole of a predetermined terminal board and then soldering or caulking the terminal. CONSTITUTION:A hole 9c to be inserted with one end 5as or 5fs of a coil 5a or 5f is made through the terminal parts 9b of a first terminal board 9. A hole 10c to be inserted with the other end 5ae or 5fe of the coil 5a or 5f for three phases is made through the terminal part 10b of a second terminal board 10. A hole 11c to be inserted with one end 5as or 5fs or the other end 5ae or 5fe of the coil 5a or 5f is made through the terminal part 11b of a third terminal board 11. One end 5as or 5fs or the other end 5ae or 5fe of each coil 5a or 5f are inserted into the through holes of each predetermined terminal and then too long coils are cut off and jointed through soldering or caulking.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a brushless motor in which a stator is disposed around the outer periphery of a rotor, and more particularly to a brushless motor in which a coil terminal treatment structure is improved.

[Conventional technology]

This type of general brushless electric motor is composed of a rotor, a stator, a housing, a bracket, a magnetic sensing element, a drive circuit, and the like.

Specifically, the rotor is provided with permanent magnets and position detection magnets having different poles alternately located in the circumferential direction on the rotor shaft. The stator surrounds the outer periphery of the rotor in a cylindrical shape, has a plurality of magnetic pole pieces protruding toward the outer circumferential surface of a permanent magnet, and has a coil wound around each magnetic pole piece. The housing has a substantially bottomed cylindrical shape, and has a stator fixed to its inner peripheral surface.

The bracket is attached to the opening of the housing, interposed between the permanent magnet and the position detection magnet.

The magnetically sensitive element is disposed in the accommodating cylindrical portion of the bracket so as to face the position detecting magnet. A drive circuit that receives a detection signal from the magnetically sensitive element controls the energization of the coil and rotates the rotor.

The coils wound around each magnetic pole piece have a so-called Y connection in which one end corresponding to each phase is connected to a drive circuit, and the other end is commonly connected. The general structure of this coil terminal treatment will be explained based on FIG. 6.

This example is a three-phase drive, with six (6 poles) magnetic poles a
l to a6 are attached to the stator at equal intervals in the circumferential direction.
The magnets protrude from the rotor toward permanent magnets (not shown), and coils b1 to b6 are wound around these.

Therefore, when the coils of the opposing magnetic pole pieces a1 and a4, a2 and a5, and a3 and a6 are energized, the magnetic poles on their tip surfaces simultaneously become the same polarity. That is, one ends bls, b3s, and b5s of the coils b1 and b4, b2 and b5, and b3 and b6 corresponding to each phase are connected to a drive circuit (not shown), and the other ends b4e and b6e, respectively.

b2e are commonly connected.

For this purpose, the other end of the coil b1 and one end of the coil b4 are connected by the connecting wire 1, the other end of the coil b3 and one end of the coil b6 are connected by the connecting wire yoke 3, and the other end of the coil b5 and one end of the coil b2 are connected by the connecting wire yoke 3. They are connected by wire-5 respectively, and coil b
4. b6. The other end of b2 is connected to common line -0.

Also, one end b1s of each coil corresponding to each phase
, b3s, and b5s are cut to appropriate lengths and passed through bracket C, and connected to gS, T, and U.
Thereby, it is connected to the drive circuit.

Such a stator ^ is press-fitted into the inner circumferential surface of the housing D, which has a substantially bottomed cylindrical shape, and is fixed to the inner peripheral surface of the housing D.
Bracket C is attached to the opening.

[Problem to be solved by the invention]

BACKGROUND OF THE INVENTION In recent years, brushless motors have been widely used in OA equipment, FA equipment, household electrical equipment such as power tools, and the like. This is because, for example, when used in a power tool, since there is no brush or commutator, the service life is dramatically extended, and there are significant advantages in that it does not become a source of noise or the like. There is a strong demand for further miniaturization and higher output for such brushless motors.

Specifically, when used in power tools, for example,
If the size is about 46 mm in diameter and 68 mm in length, the maximum output is 20014. Moreover, if the power tool is a rechargeable type, the above output must be produced by a battery of about 10V, and in that case, a maximum current of 100A will flow through the coil. In other words, in order to meet the above requirements, it is necessary to allow a large current to flow through the coil.

In order to flow such a current, the wire diameter of the coil must be set to 1.
It needs to be about 2mm thick. With this wire diameter, even if it is possible to wind it around the magnetic pole piece, in the space formed by the housing and the bracket, the above-mentioned crossover wire -1, w3°-5 or common wire WO
This makes the connection work extremely difficult.

Therefore, as shown in FIG. 7, all of the one ends bls to b6s and the other ends ble to b6e of each coil b1 to b6 are made into a substantially straight line and passed through the bracket C. and connecting wires wl and w3 formed in an arc shape. A means of connecting w5 or common line -0 can be considered.

However, if this is done, each coil b1 to b6
All both ends of and crossover wire-1, tv3. w5 or common line-
The 〇 and 〇 cross each other and the connection work is very troublesome.
Furthermore, if this is done by soldering or the like, it is difficult to guarantee that the connection is reliable.

The present invention has been made in view of the above-mentioned circumstances, and its object is to provide a brushless electric motor in which the workability and reliability of coil terminal processing can be improved.

[Means for Solving the Problem] In order to solve the problem, the brushless electric motor according to claim (1) includes permanent magnets having different poles arranged alternately in the circumferential direction and a position sensing device on the rotor shaft. a rotor provided with magnets; a stator that surrounds the outer periphery of the rotor in a cylindrical shape, has a plurality of magnetic pole pieces protruding toward the outer circumferential surface of a permanent magnet, and has a coil wound around each magnetic pole piece; A housing that has a substantially cylindrical shape with a bottom and has a stator fixed to its inner circumferential surface, a bracket that is attached to the opening of the housing and interposed between a permanent magnet and a position detection magnet, and a position detection magnet that is attached to an opening of the housing. The rotor has a magnetically sensitive element arranged to face the magnet, and a drive circuit that receives a detection signal from the magnetically sensitive element controls the energization of the coil to rotate the rotor. In a brushless motor in which one end of the corresponding coil is connected to a drive circuit and the other end of the coil corresponding to each phase is connected in common, the bracket includes a cylindrical bracket body with a flange made of an insulating material. , is composed of a number of terminal plates attached to the outer peripheral surface of the bracket body, each having an insertion hole into which the terminal end of each coil can be inserted, and the terminal plate includes a plurality of first terminal plates connecting one end of the coil. , connect the other ends of the coil in common 1
It consists of a second terminal board.

The brushless motor according to claim (2) has a configuration in which a third terminal plate serving as a crossover wire of the coils in the same phase is added to the brushless motor according to claim (1).

[Effect]

In the brushless motor according to claim (1), the terminals of each coil can be inserted into the insertion holes of a predetermined terminal plate and connected easily and reliably by soldering or caulking.

In the brushless motor according to claim (2), even when there are a plurality of coils of the same phase, the terminals of each coil can be inserted into the insertion holes of a predetermined terminal board and connected easily and reliably by soldering or caulking.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 5.

This brushless motor has a permanent magnet 2 and a position detection magnet 3.
A rotor 1 provided with a rotor 1, a stator 4 wound with coils 5a to 5f, a housing 6, a bracket 7, and a magnetically sensitive element 15.
, and a drive circuit (not shown) is the main component.

For rotation +1, a magnetic yoke 1b is press-fitted into the rotor shaft 1a, and a plurality of segmented (for example, four) permanent magnets 2 are provided on the outer periphery of the magnetic yoke 1b.

In order to hold the permanent magnet 2 more firmly, a holding protrusion with a wide tip is provided protruding from the outer peripheral surface of the magnetic yoke 1b, and the permanent magnet 2 is mounted in the space formed by this. Support side plates 1c are arranged on both sides, and a mold is made of thermosetting resin 1d.

As a result, the thermosetting resin 1d fills the through hole 1e of the magnetic yoke 1b and the gap between the permanent magnet 2 and the holding protrusion, and the permanent magnet 2 is firmly held. In the permanent magnet 2 thus provided, different poles are alternately located in the circumferential direction.

The position detection magnet 3 is attached to the rotor shaft 1 which is separate from the permanent magnet 2.
It is provided at one end of a. This position detection magnet 3 has a ring plate shape and is bonded to a support disk 3a, which is fixed to the rotor shaft 1a. Also, like the permanent magnet 2, different poles are alternately located in the circumferential direction.

The stator 4 is made by punching and laminating magnetic thin plates.
A plurality of (six in this embodiment) magnetic pole pieces 4a surround the outer circumference of the rotor 1 in a cylindrical shape and are directed toward the outer circumferential surface of the permanent magnet 2.
4f to 4f are made to protrude. Therefore, this electric motor is 3-phase excited and has two magnetic poles of the same phase. The magnetic pole pieces 4a to 4f have wide tip portions that serve as magnetic poles. Then, coils 5a to 5f are wound around each of the poles 4a to 4f except for their tip portions via an insulating member.

Each coil 5a to 5f is wound with a thick wire having a diameter of about 1.2 mm, and one end thereof (for example, the winding start side) 5aS
5fs to 5fs and the other end (for example, winding end side) 5ae to 5
A total of 12 terminals of fe protrude from the end surface of the stator 4 in a straight line parallel to the axis. Of these six coils, there are also two coils each having the same phase.

The housing 6 has a substantially cylindrical shape with a bottom, and is provided with a bearing stand 6c having a bearing 6b at the center of the bottom thereof.

A press-fitting protrusion 6d, a positioning part 6e, a removal stop part 6f, etc. are formed on the inner peripheral surface of the stator 4.
is press-fitted and fixed.

The bracket 7 includes a bracket main body 8 and a number of terminal plates 9°10.1 made of conductive material such as copper and having a thickness of approximately 0.5 m.
It consists of 1.

The bracket main body 8 is made of thermoplastic resin such as nylon 66 and has a cylindrical shape with a flange. For details, see flange 8a.
have an outer diameter large enough to close the opening of the housing 6, and are spaced at approximately equal intervals through which the ends of the coils 5a to 5f are inserted.
, 8b, -.-, and a protrusion 8c + 8 protruding from the end surface.
c +-・- is provided. The cylindrical portion 8d is the coil 5a.
It has an outer diameter that does not interfere with the protrusion of each terminal of the terminals 5f to 5f, and has four rows of circumferential grooves S1 and S2 in the axial direction on its outer circumferential surface in order to attach a terminal plate, which will be described later, to a predetermined position. ．． S3.
S4 is provided. These circumferential grooves Sl, S2. S3. S4 is formed by molding with a side core type metal mold or by cutting. Further, a partition wall 8e with a center hole is provided in the inner intermediate part of the cylindrical portion 8d, and a bearing stand 6c having a bearing 6b is provided in the inner space formed by this, and a position detection magnet is placed in the outer space. 3 and a magnetically sensitive element described later are housed therein.

Reference numeral 12 denotes a bracket plate, which is formed by punching out a metal plate to have approximately the same diameter as the outer diameter of the alligator portion 8a, in order to reinforce the bracket main body 8. This also includes the U groove 8b of the bracket body 8,
8b, - and protrusion 3c, U groove 12 corresponding to 8c+''-
b, 12b, -, holes 12c, 12c, -, and center hole 12a are provided. In this embodiment, a bearing stand 6c is provided in the center hole 12a, and projections 8c are provided in the holes 12c, 12c, .
The outer diameter portions of +8c and +- are respectively caulked and fixed to the opening of the housing 6.

A plurality of (three in this embodiment) first terminal plates 9 include an arc-shaped base 9a and a terminal portion 9b protruding outward from an intermediate portion thereof.
The terminal portion 9b has one end of the coils 5a to 5f (
For example, on the winding start side), an insertion hole 9c (U-groove in the embodiment) through which the threads 5as to 5fs can be inserted is formed. The center angle throughout the circumference of this base portion 9a is approximately 30°.

One second terminal FilO has an arc-shaped base 10a and three terminal parts 10b, 10b, 10b that protrude outward.
Each terminal portion 10b has the other end of the coils 5a to 5f (for example, the winding end side), and an insertion hole 10c (in the embodiment, a U groove) through which each phase silver of the coils 5ae to 5fe, that is, three pieces, can be inserted. ) is formed. These terminal parts 10b, 10b
, 10b are set at a center angle of about 60'', and therefore the center angle is slightly larger than about 120° around the circumference of the base 10a.

A plurality of (three in this embodiment) third terminal boards 11 have an arc-shaped base 11a and two terminal parts 11b that protrude outward, and the terminal parts 11b include coils 5a to 5f. The other end (
For example, an insertion hole 11c (U groove in the embodiment) through which 5ae to 5fe (for example, at the end of winding) or 5as to 5fs (for example, at the beginning of winding) can be inserted is formed. The mutual spacing between the terminal portions 11b and llb is approximately 30 degrees at the center angle, and therefore the center angle is approximately 120 degrees around the circumference of the base portion 11a.
Make it slightly larger.

Four rows of circumferential grooves S1. S2. S3. S4 is set as follows. The outermost circumferential groove S1 has a circumferential length for attaching the three first terminal plates 9, and has two small partitions so that the insertion holes 9c are located at 60° intervals. .

The second row of circumferential grooves 32 has a circumferential length for attaching only one third terminal plate 11, and this third terminal plate 11 is
Since these are crossover wires of the same phase, the insertion hole 11c is set to be positioned 60' apart from the insertion hole 9c of the first terminal plate 9.

The third row of circumferential grooves 33 also has a circumferential length for attaching only one third terminal plate 11. This third terminal plate 11 is a crossover wire of the same phase that is different from that attached to the circumferential groove 82 in the second row, so it is positioned 60° in the circumferential direction from the third terminal plate 11 in the second row. Set to

The fourth row of circumferential grooves 34 connects the remaining third terminal plate Il and 1
It has a circumferential length for attaching two second terminal plates 10. This third terminal plate 11 is positioned 60° in the circumferential direction from that of the third row. Set each phase so that a total of three of them can be connected in common.

Reference numeral 13 denotes a terminal plate holder, which is made of a plastic material and is formed into a cylindrical comb-teeth shape whose inner diameter is the same as the outer diameter of the cylindrical portion 8d of the bracket main body 8. This is to ensure that each terminal board is attached more securely, and the 12 comb teeth 13a are designed to form a gap slightly larger than the width of each terminal board.
have. This terminal plate holder 13 holds each terminal plate in predetermined circumferential grooves Sl, S2. After attaching to S3 and S4,
It is press-fitted onto the outer periphery of the cylindrical portion 8d.

One end of each coil 5a to 5f (for example, winding start side) 5a
S to 5fs and the other ends (for example, the winding end side) 5ae to 5fe are inserted into the insertion holes of the respective predetermined terminals, and those that are too long are cut as appropriate and connected and fixed by soldering or caulking. Then, lead wires 14 connected to a drive circuit (not shown) are connected to the three first terminal plates 9 by soldering or the like.

For example, a Hall element is used as the magnetically sensitive element 15, and the plate 15 is mounted so as to face the outer peripheral surface of the position detection magnet 3.
provided in a. When facing the N pole of the position detection magnet 3, it detects this and transmits the signal to the lead wire 15b.
It is input to the drive circuit (not shown) via. The above installation is board 1
5a has an abbreviated shape and is screwed onto the attachment portion 8f of the bracket main body 8 with a screw 16.

In such a brushless electric motor, a detection signal from the magnetically sensitive element 15 is input to a drive circuit, and the drive circuit activated by the detection signal controls energization of the coil, thereby causing the rotor 1 to rotate.

Incidentally, when there is not a plurality of in-phase terminals as in this embodiment, the third terminal board, which is the in-phase connecting wire, can be omitted.

〔Effect of the invention〕

In the brushless motor according to claim (1), the terminals of each coil can be inserted into the insertion holes of a predetermined terminal board and connected easily and reliably by soldering or caulking, thereby improving the workability and reliability of coil terminal processing. Improves sexual performance.

In the brushless motor according to claim (2), even when there are a plurality of coils of the same phase, the terminal of each coil can be inserted into the insertion hole of a predetermined terminal plate by providing the third terminal plate which is a connecting wire. It can be easily and reliably connected by soldering or caulking, improving the workability and reliability of coil terminal processing.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, FIG. 2 is an exploded view of the main part thereof, FIG. 3 is a perspective view of the main part showing the terminal of the coil, Figure 4 shows
It is a top view of each terminal board, (a) is a 1st terminal board, (b)
is the second terminal plate, (c) is the third terminal plate, FIG. 5 is an explanatory diagram of the circumferential groove of the bracket, (a) is a longitudinal cross-sectional view, (b) is a LA cross-sectional view, (c) is an explanatory diagram of the peripheral groove of the bracket. is a BB cross-sectional view, (d) is a C-C cross-sectional view, (e) is a D-D cross-sectional view, Fig. 6 is a perspective view of the main part showing the terminal of a conventional coil, and Fig. 7
The figure is a perspective view of a main part showing the terminal of another conventional coil. 1-rotor, 1a-rotor shaft, 1b-magnetic yoke, 2-
・Permanent magnet, 3...Position detection magnet, 4-Stator, 4
a to 4f - magnetic pole, 5a to 5f - coil, 5as to 5fs - one end, 5ae to 5fe - other end, 7 - bracket, 8 - bracket body, 8a - flange, 8b - U groove, 8d -
Cylindrical part, Sl, S2. S3. S4-circumferential groove, 9-first terminal plate, 9a-base, 9b-one terminal part, 9c-insertion hole, 10-second terminal plate, 10a-base, l0b-one terminal part, 1
0c - insertion hole, 11 - third terminal plate, 1la - base, 11b - terminal part, 1
1c--Insertion hole, 14-Lead wire, 15-Magnetic sensing element, 15b-Lead wire.

Claims (2)

[Claims] (1) A rotor in which permanent magnets and position detection magnets with different poles alternately located in the circumferential direction are installed on the rotor shaft, and the outer circumference of the rotor is surrounded by a cylindrical shape, and the outer circumferential surface of the permanent magnet is A stator with a plurality of magnetic poles protruding from each other and a coil wound around each magnetic pole, a housing that is approximately cylindrical in shape with a bottom and the stator fixed to its inner circumferential surface, a permanent magnet, and a position sensor. The bracket is interposed between the magnet for position detection and is attached to the opening of the housing, and the magnetically sensitive element is arranged to face the magnet for position detection, and receives a detection signal from the magnetically sensitive element. The drive circuit controls the energization of the coils to rotate the rotor, and one end of the coil corresponding to each phase is connected to the drive circuit, and the other end of the coil corresponding to each phase is connected in common. In the brushless electric motor, the bracket includes a cylindrical bracket body with a flange made of an insulating material, and a plurality of brackets attached to the outer circumferential surface of the bracket body, each having an insertion hole through which an end of each coil can be inserted. The terminal board consists of a plurality of first terminal boards that connect one end of the coil, and one terminal board that commonly connects the other end of the coil.
A brushless electric motor comprising a second terminal plate. (2) A brushless electric motor according to claim (1), characterized in that a third terminal plate serving as a connecting wire for coils of the same phase is added.