JPH10271796A - Stepping motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stepping motor in which the winding work around a bobbin 15 enhanced while miniaturizing the motor itself. SOLUTION: The stepping motor comprises annular cores (stator cores) 2, 3 having annular bobbins 22, 32 where coils 21, 31 are wound around the winding parts 25, 35, a rotor 1 having a rotary shaft 11 being set in the annular cores 2, 3, a circuit board 6 disposed oppositely to the outer surface of the annular cores 2, 3, and conduction terminals 7, 8 held on the annular bobbins 22, 32 while being insulated. The conduction terminal 7, 8 is provided with first connecting parts 71, 81 to be connected electrically with the coil 21, 31, and a second connecting part 72, 82 extending through the winding part 25, 35 of the annular bobbin 22, 32 along the axial direction of the rotor 1 and connected, electrically with the the connection terminal 9 of the circuit board 6. Furthermore, the winding part 25, 35 of the annular bobbin 22, 32 is provided with a part 38 for connecting the terminal 9 electrically with the conduction terminal 7, 8 by inserting the terminal 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stepping motor, and more particularly, to an electric connection structure between a circuit board and a coil in a stepping motor having a circuit board.

[0002]

2. Description of the Related Art For example, PM (permanent magnet) type stepping motors have been widely used as actuator parts in various industrial fields, and most of such stepping motors have a stator core provided with a bobbin wound with a coil. A rotor made of a permanent magnet is housed in the hollow of the rotor, and the rotor is driven to rotate by the magnetic field of a coil according to an electric signal. It is also attracting attention as a drive source for analog instruments.

[0003] Such a stepping motor is disclosed in, for example, Japanese Patent Application Laid-Open Nos. 5-64411 and 8-1-1.
As disclosed in Japanese Patent Publication No. 11971, an electrical connection between the coil and the external circuit board is made through an energizing terminal insulated and fixed to the bobbin on the outer periphery of the stator core corresponding to the centrifugal direction of the rotor. The terminal has one end extending in the centrifugal direction of the rotor and electrically connected to the coil, and the other end extending in the axial direction of the rotor and electrically connected to the external circuit board. Is electrically connected to a coil or an external circuit board by soldering or the like, and realizes a simple connection structure without using a connector, an electric cord, a flat cable, or the like.

[0004]

However, in such a connection structure using the current-carrying terminals, the other end of the current-carrying terminal extending toward the circuit board is located on the outer periphery of the winding portion of the bobbin. Winding workability is poor as an obstacle to coil winding, and considering the winding workability, it is necessary to increase the distance between the stator core and the other end of the current-carrying terminal, which increases the size of the motor itself. There's a problem.

The present invention has been made in view of this point, and an object of the present invention is to provide a stepping motor capable of improving the workability of winding a bobbin and achieving downsizing of the motor itself.

[0006]

According to the present invention, there is provided a stator core having a bobbin having a coil wound around the outer periphery of a hollow cylindrical winding portion, and a center portion of the stator core accommodated in the bobbin winding portion. A rotor having a rotating shaft rotated by the magnetic field of the coil, a circuit board opposed to an outer surface of the stator core corresponding to an axial direction of the rotor; and the coil and the circuit board insulated and held by the bobbin. A stepping motor provided with an energizing terminal for electrically connecting the bobbin with the first connecting portion, wherein the energizing terminal is electrically connected to the coil, and the bobbin is wound integrally with the first connecting portion. A second connection portion that extends in the wire portion along the axial direction of the rotor and is electrically connected to a rod-shaped connection terminal that is conductively fixed to the circuit board; With the second connecting portion exposed, the rotor extends in the axial direction of the rotor, and one end side opens to the circuit board side, and the connecting terminal is inserted to connect the connecting terminal and the second connecting portion of the energizing terminal. An insertion portion for electrical connection is formed.

[0007] An extension portion for guiding the connection terminal into the insertion portion is formed at a position corresponding to the insertion portion of the bobbin.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A stepping motor according to the present invention has a stator core having a bobbin in which a coil is wound around the outer periphery of a hollow cylindrical winding portion, and is housed in the winding portion of an annular bobbin around the center of the stator core. A rotor having a rotating shaft disposed and rotated by the action of a magnetic field of a coil; a circuit board disposed to face an outer surface of a stator core corresponding to an axial direction of the rotor; and the coil and the circuit board insulated and held by the bobbin. And a first connecting portion that extends in the centrifugal direction of the rotor, protrudes from the bobbin, and is electrically connected to the coil, and the first connecting portion is formed integrally with the first connecting portion. A second connecting portion that extends in the winding portion of the bobbin along the axial direction of the rotor and is electrically connected to a rod-shaped connecting terminal that is conductively fixed to the circuit board; An insertion portion is formed in the winding portion of the bobbin so as to extend in the axial direction of the rotor while exposing the second connection portion of the current-carrying terminal, and one end of the bobbin is open to the circuit board. The connection terminal is inserted into the insertion portion. By doing so, the electrical connection between the connection terminal and the second connection portion of the conduction terminal is achieved. In this way, the second connection portion serving as a connection portion to the circuit board extends in the bobbin winding portion in the axial direction of the rotor, so that the current-carrying terminal does not hinder the coil winding, and Since the second connecting portion does not protrude to the outer periphery of the stator core, the structure is compact.

[0009] Further, by forming an extension portion for inserting and guiding the connection terminal into the insertion portion at the bobbin position corresponding to the insertion portion, the workability of connection between the connection terminal and the energizing terminal is improved, and the connection terminal is connected to the connection terminal in the connected state. Good insulation with other members is maintained.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a perspective view of a stepping motor according to a first embodiment of the present invention, FIG. 2 is an exploded perspective view of the stepping motor of FIG. 1, FIG. 3 is a sectional view of FIG. 1, and FIG. FIG.

As shown in FIGS. 1 to 3, the stepping motor according to this embodiment has a rotor 1 and a first annular structure which forms a concentric laminated body so as to be housed inside the rotor 1 so as to surround it. A stator core 2 and a second annular stator core 3 (stator core) are disposed so as to face each other so as to sandwich the annular stator cores 2 and 3 along the axial direction of the rotor 1, and a third holding the rotor 1 in each annular stator core 2 and 3. 1, a second holding member 4, 5 mounted on a circuit board 6 along the axial direction of the rotor 1 and mounted on the circuit board 6.
Is connected to the power supply.

The rotor 1 is composed of a permanent magnet having a plurality of magnetic poles alternately arranged N and S along the direction of rotation on the circumferential surface in the centrifugal direction. Are fixed, and the first and
The bearing is held by the second holding members 4 and 5.

The first annular stator core 2 includes a coil 21
An annular bobbin (bobbin) 22 around which is wound, a substantially annular cup-shaped outer yoke 23 made of a magnetic metal material, and a substantially annular plate-shaped inner yoke 24 also made of a magnetic metal material. The yokes 23 and 24 are stacked concentrically so as to sandwich the annular bobbin 22 therebetween.

The annular bobbin 22 has a hollow cylindrical winding portion 25 in which the coil 21 is wound on the outer periphery and in which the rotor 1 can be accommodated, and an axial direction of the winding portion 25 (rotor 1).
Axial direction) of the coil 2
Flange 2 which also has a function of a winding guide when winding 1
6, 27, and a flange portion 27 located on the lower side in the figure.
Is formed with a guide portion 27a for guiding the end portion 21a of the exciting coil 21 to an energizing terminal described later.

In the assembled state, a plurality of pole teeth 23a, 24a formed on the outer and inner yokes 23, 24 are housed and arranged along the inner wall of the winding portion 25. At this time, the pole teeth 23a and 24a
5, the rotor 1 is combined with an annular comb-shaped arrangement slightly larger than the outer diameter of the rotor 1 in the centrifugal direction.
And a predetermined distance from each other.

The second annular stator core 3 has substantially the same configuration as the first annular stator core 2,
1 comprises an annular bobbin (bobbin) 32, a substantially annular cup-shaped outer yoke 33 made of a magnetic metal material, and a substantially annular plate-shaped inner yoke 34 also made of a magnetic metal material. The inner yokes 33 and 34 are concentrically stacked so as to sandwich the annular bobbin 22 therebetween.

The annular bobbin 32 has a hollow cylindrical winding portion 35 in which the coil 31 is wound on the outer periphery and in which the rotor 1 can be accommodated, and an axial direction of the winding portion 35 (rotor 1).
The coil 3 is formed so as to form a pair on the outer periphery of both ends.
Flange part 3 which also has a function of a winding guide when winding 1
6,37.

In the assembled state, a plurality of pole teeth 33a, 34a formed on the outer and inner yokes 33, 34 are housed and arranged along the inner wall of the winding portion 35. At this time, the pole teeth 33a, 34a
5, the rotor 1 is combined with an annular comb-shaped arrangement slightly larger than the outer diameter of the rotor 1 in the centrifugal direction.
Of the pole teeth 33a, 34a and the pole teeth 23a, 2a.
The arrangement phases 4a are combined with a predetermined phase difference in the rotation direction of the rotor 1.

The first and second annular stator cores 2 and 3 configured as described above are laminated concentrically along the axial direction of the rotor 1 to form a laminated body having a hollow interior. The rotor 1 is accommodated in the hollow, and the rotating shaft 11 of the rotor 1 is held by the first and second bearing plates 4 and 5,
The motor main body thus configured is mounted on the circuit board 6 as described above, whereby the circuit board 6 is positioned on the outer surface of the annular stator core 3 on the rear side in the axial direction.

By the way, in the case of the present embodiment, the winding operation of the coils 21 and 31 on the respective annular bobbins 22 and 33 is performed by the first and the second operations.
This is performed after the second annular stator cores 2 and 3 are stacked and combined.

That is, among the first and second annular stator cores 2 and 3, the annular bobbin 32 which is a component of the second stator core 3 has a substantially L-shape (see FIGS. 3 and 4). A pair of plate-like current-carrying terminals 7 and 8 are fixed by insert molding. After the first and second annular stator cores 2 and 3 are combined into a laminated body, a coil 21 is provided on one side of the current-carrying terminals 7. The coil 21 having the (one side) end portion 21a of which the winding start portion is conductively fixed and the winding start portion of which is fixed to the energizing terminal 7 is wound around the annular bobbin 21 through the guide groove 27 of the annular bobbin 21. The winding end portion of the coil 21 that is wound around the portion 25 and forms the (other side) terminal portion 21a is conductively fixed to the energizing terminal 7 on the other side. On the other hand, on one side of the energizing terminal 8, the (one side)
The coil 31 having the winding start portion constituting the coil 1a is fixed in a conductive state, and the winding start portion is fixed to the energizing terminal 8.
The winding end of the coil 31 constituting the (other side) terminal portion 31a is wound around the winding portion 35 of
Is electrically fixed.

Thus, the windings of the coils 21 and 31 to the annular bobbins 22 and 32 and the conductive connection between the coils 21 and 31 and the energizing terminals 7 and 8 are made. Before the first and second annular stator cores 2 and 3 are combined, the annular bobbin 32 can be used alone. The energizing terminal 7 may be fixed to the annular bobbin 22. By separately fixing the energizing terminals 7 and 8 to the annular bobbins 22 and 32, the coils 21 and 31 are wound around the annular bobbins 22 and 33. Can be performed individually for the annular bobbins 22, 33.

As shown in detail in FIGS. 3 and 4, the energizing terminals 7, 8 extend inside the flange portion 36 of the annular bobbin 32 along the centrifugal direction of the rotor 1 and extend in the same direction. First connecting portions 71 and 81 projecting from side ends
And second terminal portions 72 and 82 extending along the axial direction of the rotor 1 in the winding portion 35 of the annular bobbin 32 integrally with the first connecting portions 71 and 81. The coils 21, 31 (ends 21 a, 31 a) are conductively fixed to the extension ends of the first terminal portions 71, 81 as described above, and the second connection portions 72, 82 have elasticity. The contact portions 73 and 83 are formed to protrude, and connection terminals described later are electrically connected to the contact portions 73 and 83.

On the other hand, the winding portion 3 of the annular bobbin 32 corresponding to the region of the second connection portions 72 and 82 including the contact portions 73 and 83
A rectangular hole-shaped insertion portion 38 extending in the axial direction of the rotor 1 and opening to the circuit board 6 side is formed in the five regions, and a second connection including contact portions 73 and 83 in the insertion portion 38 is formed. Part 7
When the connection terminal is inserted into the insertion portion 38, the contact portions 73 and 83 and the connection terminal are elastically contacted, and both are electrically connected. . .

The annular bobbin 3 corresponding to the insertion portion 38
Extension portions 39 are formed at two positions so as to surround the opening of the insertion portion 38 and extend toward the circuit board 6 (in the axial direction of the rotor 1) and guide the connection terminals into the insertion portion 38. The outer periphery of 39 is fitted in the outer yoke 33 and the through holes 33b and 51 formed in the second bearing plate 5 corresponding to the extension 39 in the assembled state, whereby the connection terminal and the outer yoke 33 and the second yoke 33 are fitted. Also has a function of preventing a short circuit due to contact with the bearing plate 5.

The circuit board 6 is provided with a drive circuit (not shown) for supplying electric signals for driving the motor to the coils 21 and 31. The drive circuit and the connection terminals 9 are electrically connected to each other through a circuit pattern (not shown). Have been.

The connection terminal 9 is fixed to the position of the circuit board 6 corresponding to the second connection portions 72, 82 (the insertion portion 38 of the annular bobbin 32) of the power supply terminals 7, 8 by means such as soldering. When the motor body is mounted on the circuit board 6 along the axial direction of the rotor 1, the motor body is inserted into the insertion portion 38 of the annular bobbin 32, and the connection terminal 9 and the contact portions 73 and 83 are electrically connected, thereby driving the motor. Circuit → Circuit pattern → Connection terminal 9
An electric signal supply line composed of → contact portions 73 and 83 → second connection portions 72 and 82 → first connection portions 71 and 81 → coils 21 and 31 is formed.

As described above, in this embodiment, the annular stator core (stator core) 2 having the annular bobbins (bobbins) 22 and 32 around which the coils 21 and 31 are wound around the outer periphery of the hollow cylindrical winding portions 25 and 35. , 3 and a rotor 1 having a rotating shaft 11 housed in the winding portions 25, 35 of the annular bobbin at the center of the annular stator core and rotated by the magnetic field of the coils 21, 31; A circuit board 6 opposed to the outer surfaces of the annular stator cores 2 and 3 corresponding to the axial direction of the coil, and energizing terminals 7 insulated and held by the annular bobbins 22 and 32 and electrically connecting the coils 21 and 31 to the circuit board 6. , 8 are connected to the first terminals 7, 8 extending in the centrifugal direction of the rotor 1 and projecting from the annular bobbins 22, 32 and electrically connected to the coils 21, 31.
1 and 81 and the first connecting portions 71 and 81 are integrated with each other so that the inside of the winding portions 25 and 35 of the annular bobbins 22 and 32 is
The second connecting portions 72 and 8 extending along the axial direction of the first connecting portion and electrically connected to the rod-shaped connecting terminals 9 which are conductively fixed to the circuit board 6.
2 and the annular bobbins 22 and 32 have
The connection terminals are extended by extending the rotor 1 in the axial direction with the second connection portions 72 and 82 of the power supply terminals 7 and 8 being exposed to the terminals 5 and 35 and having one end opened to the circuit board 6 side and inserting the connection terminals 9. 9 is a second connecting portion 72, 8 of the conducting terminals 7, 8
By forming the insertion portion 38 that contacts the connection terminal 9 to electrically connect the connection terminals 9 and the energization terminals 7 and 8 by contact with the circuit board 6, the second connection portion serving as a connection portion to the circuit board 6 is formed by the rotor inside the bobbin winding portion. The current-carrying terminals 7 and 8 are
1, 31 does not become an obstacle when winding, the winding workability can be improved, and the second connecting portion 7
Since the members 2 and 82 do not protrude to the outer periphery of the annular stator cores 2 and 3, the structure becomes compact and downsizing can be achieved.

The annular bobbin 2 corresponding to the insertion portion 38
By forming an extension portion for guiding the connection terminal 9 insulated in the insertion portion 38 at the positions 2 and 32, the workability of connection between the connection terminal 9 and the conducting terminals 7 and 8 is improved, and the connection terminal 9 in the connected state is improved. And the other members (outer yoke 33, second bearing plate 5) can be maintained in a good insulation state.

In this embodiment, the second terminals of the current-carrying terminals 7 and 8
Are formed in the shape of a plate.
Depending on the thickness of the winding portions 25, 35, the second connection portions 72, 82 are formed in a frame shape, and the second connection portions 72, 82 are formed in a frame shape.
The contact portions 73 and 83 may be formed on the connection portions 72 and 82 of the first embodiment.

[0032]

As described above in detail, the present invention relates to a stator core having a bobbin in which a coil is wound around the outer periphery of a hollow cylindrical winding portion, and a center portion of the stator core and inside the bobbin winding portion. A rotor provided with a rotating shaft that is housed and arranged to rotate by the action of a magnetic field of the coil, a circuit board that is arranged to face the outer surface of the stator core corresponding to the axial direction of the rotor, and the coil that is insulated and held by the bobbin. A stepping motor including an energizing terminal for electrically connecting the circuit board, wherein the energizing terminal is integrated with a first connection portion electrically connected to the coil and the first connection portion. A second connection portion that extends in the bobbin winding portion along the axial direction of the rotor and is electrically connected to a rod-shaped connection terminal conductively fixed to the circuit board; Through A second connection portion between the connection terminal and the current-carrying terminal is extended by extending the rotor in the axial direction with the second connection portion of the terminal being exposed, and having one end opening to the circuit board side and inserting the connection terminal. By forming an insertion portion for electrically connecting the motor to the stepping motor, it is possible to provide a stepping motor capable of improving workability of winding the bobbin and achieving downsizing of the motor itself.

Further, according to the present invention, the extension of the bobbin for guiding the insertion of the connection terminal into the insertion portion at the position corresponding to the insertion portion improves the workability of connection between the connection terminal and the current-carrying terminal. In addition, it is possible to maintain a good insulation state between the connection terminal and the other members in the connection state.

[Brief description of the drawings]

FIG. 1 is a perspective view of a stepping motor according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of FIG.

FIG. 3 is a sectional view of FIG. 1;

FIG. 4 is a perspective view showing a single conducting terminal.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Rotor 2, 3 First and second annular stator core (stator core) 6 External circuit board 7, 8 Current supply terminal 11 Rotary shaft 21, 31 Coil 22, 32 Annular bobbin (bobbin) 25, 35 Winding part 38 Insertion part 39 Extension 71, 81 First connection 72, 82 Second connection 73, 83 Contact

Claims (2)

[Claims] 1. A stator core having a bobbin around which a coil is wound around the outer periphery of a hollow cylindrical winding portion, and a center portion of the stator core, which is accommodated in the bobbin winding portion and is rotated by the magnetic field of the coil. A rotor provided with a rotating shaft, a circuit board opposed to the outer surface of the stator core corresponding to the axial direction of the rotor, and a power supply insulated by the bobbin for electrically connecting the coil to the circuit board. A first connecting portion in which the current-carrying terminal is electrically connected to the coil; and a first connecting portion integrated with the first connecting portion, the inside of the winding portion of the bobbin extending in the axial direction of the rotor. A second connection portion that extends along the second connection portion and is electrically connected to a rod-shaped connection terminal that is conductively fixed to the circuit board.
With the connecting portion exposed, the rotor extends in the axial direction of the rotor, and one end side opens to the circuit board side, and the connection terminal is inserted into the second connection terminal and the second connection terminal.
A stepping motor characterized by forming an insertion portion for electrically connecting the connection portion of the stepping motor. 2. The stepping motor according to claim 1, wherein an extension for guiding the connection terminal into the insertion portion is formed at a position corresponding to the insertion portion of the bobbin.