JP2009278696A - Small electric motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cope with thinning of a small motor without worsening the motor characteristics. <P>SOLUTION: A protrusion 26 includes integrally a synthetic resin insulating layer 25 which is provided on the surface of a stator core 22, and the terminal 27a of a coil 27 wound on the insulating layer 25 is tied to the protrusion 26. The terminal 27a tied to the protrusion 26 is connected electrically with the land 34 of a circuit board 32 by soldering in a state where the protrusion 26 is inserted into the through-hole 33 of the circuit board 32. Since the protrusion 26 to which the terminal 27a of a coil 27 is tied is provided integrally with the insulating layer 25, a strength of the protrusion 26 is ensured on contrary to the case where insert molding of a metal connection terminal of another member is carried out on the insulating layer 25, and since it is not necessary to form a through-hole for fixing a connection terminal in the stator core 22, the motor characteristics is prevented from deteriorating. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a small electric motor that is improved particularly in a small and thin electric motor in which a terminal of a coil wound around a stator core is connected to a coil connecting portion of a circuit board.

  In an electric motor, as a method for connecting a coil terminal wound around a stator to a coil connection part of a circuit board, a coil terminal drawn from the stator is connected to a coil connection part (such as a land part of a circuit board) on the circuit board. In addition, there is known a method of connecting by soldering while pressing with a jig such as tweezers, but there is a problem that workability is poor. In particular, when the electric motor is miniaturized, workability is further deteriorated.

In consideration of assembly by an automatic machine, an insulating layer of synthetic resin is provided on the surface of the stator core, and conductive connection terminals (pins) are inserted into the insulating layer so as to protrude in the axial direction of the stator core. A coil terminal provided by molding and wound around an insulating layer is entangled with the connection terminal, and after pre-soldering the coil terminal and the connection terminal, the connection terminal and the coil connection part of the circuit board are electrically connected. For example, a device that is connected in a conventional manner is known (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 11-18392

  By the way, as in Patent Document 1, a synthetic resin insulating layer is provided on the surface of the stator core, a conductive connection terminal is provided on the insulating layer by insert molding, and a coil terminal wound around the insulating layer is used as the connection terminal. In the binding method, in order to secure the attachment strength of the connection terminal, the thickness of the insulating layer (synthetic resin layer) around the base end portion of the connection terminal is required. In this case, it is good if the thickness of the insulating layer can be ensured, but when the downsizing or thinning is required, the axial thickness may not be particularly secured.

  Therefore, in order to secure the mounting strength of the connection terminal, it is considered to provide the connection terminal in a through state in a flat stator core. An example is shown in FIGS. These FIG. 13 and FIG. 14 show a thin outer rotor type small electric motor. In the stator 1, a synthetic resin insulating layer 3 is provided on the surface of a flat stator core 2, and a coil 4 is wound on the insulating layer 3. A through hole 2 a is formed in the stator core 2, and a conductive rod-like metal connection terminal 5 is provided in the through hole 2 a in a penetrating state, and a base end portion is fixed by an insulating layer 3. A synthetic resin also enters the through hole 2a. A terminal 4 a of the coil 4 is entangled with the connection terminal 5. The stator 1 is fixed to the support portion 6 a of the base 6.

  A circuit board 7 is fixed to the base 6. The circuit board 7 is formed with a through hole 7a and a land portion 7b for connecting the coil, and the connection terminal 5 and the land portion 7b are electrically connected by the solder 8 with the connection terminal 5 inserted into the through hole 7a. Connected.

  The rotor 9 includes a ring-shaped rotor yoke 10, a rotor magnet 11 fixed to the inner peripheral portion of the rotor yoke 10, a synthetic resin rotating plate 12 that supports the rotor yoke 10, and a central portion of the rotating plate 12. The rotary shaft 13 is provided, and the rotary shaft 13 is rotatably supported by the support portion 6 a of the base 6. The rotor magnet 11 is opposed to the outer peripheral surface of the stator core 2 with a predetermined gap from the radial direction.

  In such a configuration, the stator core 2 is provided with the through hole 2a for holding the connection terminal 5 in order to secure the attachment strength of the connection terminal 5, so that the magnetic characteristics are deteriorated and the motor characteristics are improved. There is a problem that causes a decrease.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a small electric motor that can cope with a reduction in thickness without deteriorating motor characteristics.

  In order to achieve the above-described object, a small electric motor according to a first aspect of the present invention includes a flat stator core, an insulating layer made of synthetic resin so as to cover the surface of the stator core, and the insulating layer on the insulating layer. A protrusion provided integrally at the time of molding, a coil wound on the insulating layer, and a terminal having a terminal entangled with the protrusion, a coil connection part, and the entangled with the protrusion The terminal of the coil comprises a circuit board electrically connected to the coil connection part.

  In order to achieve the same object, a small electric motor according to claim 7 includes a flat stator core, an insulating layer made of a synthetic resin so as to cover the surface of the stator core, and a radial direction of the stator core on the insulating layer. A metal connection terminal attached in a form protruding toward the terminal, a coil wound on the insulating layer, and a terminal entangled with the connection terminal, a coil connection portion, and the connection terminal The end of the coiled coil comprises a circuit board electrically connected to the coil connection part.

  In the small electric motor according to the first aspect of the present invention, since the projecting portion for tying the end of the coil is integrally provided in the insulating layer, it is different from the case where a separate metal connection terminal is insert-molded in the insulating layer. The strength of the protrusion can be ensured, and the thickness can be reduced. Further, since it is not necessary to form a through hole for attaching the connection terminal in the flat stator core, it is possible to suppress deterioration of the motor characteristics.

  In the small electric motor according to the seventh aspect, the conductive connection terminal provided in the insulating layer is attached in a form protruding toward the radial direction of the flat stator core, so that the attachment strength of the connection terminal is secured. However, it becomes possible to cope with the thinning. Further, since it is not necessary to form a through hole for attaching the connection terminal in the stator core, it is possible to suppress deterioration of the motor characteristics.

(First embodiment)
Hereinafter, a first embodiment in which the present invention is applied to a thin outer rotor type small motor will be described with reference to FIGS. In FIG. 1, the stator core 22 in the stator 21 in this case is a flat one formed by punching a single steel plate, and as shown in FIG. A circular opening 22a is formed in the part. Each tooth 23 has a distal end portion 23a whose outer peripheral surface forms an arc shape, and a proximal end portion 23b that is formed to have a width in the circumferential direction narrower than the distal end portion 23a, and is substantially T-shaped. Between adjacent teeth 23, a slot 24 having an open outer peripheral side is formed. An insulating layer 25 made of a synthetic resin is provided on the surface of the stator core 22 by molding. Of the surface of the stator core 22, the outer peripheral surface of the tip 23 a of each tooth 23 and the peripheral edge of the opening 22 a at the center are not provided with the insulating layer 25, and the stator core 22 is exposed.

  In the insulating layer 25, a plurality of protrusions 26 protruding in the axial direction are integrally provided on the insulating layer 25 by being positioned on one end face side in the axial direction of the stator core 22. In this case, four protrusions 26 are provided. In this case, each protrusion 26 has a cylindrical shape and is disposed at a portion corresponding to the tip 23 a of the tooth 23. A coil 27 (see FIG. 3) is wound on the insulating layer 25 at the base end portion 23 b of each tooth 23. A base end portion 23 b of each tooth 23 corresponds to a winding portion of the coil 27.

  Although the winding method of the coil 27 differs depending on the type of motor (single-phase motor or three-phase motor) and winding specifications, the terminal 27a of the coil 27 (terminal of winding start or terminal of winding end) is connected to the protrusion 26. Keep it tied. In the example of FIG. 3, the coil 27 has three phases, and the terminal 27 a of each phase of U, V, and W is individually entangled with the corresponding three protrusions 26, and one protrusion 26 has Terminals 27a for three phases are entangled. When the terminal 27 a of the coil 27 is entangled, the terminal 27 a is entangled slightly toward the distal end side from the base end (root) of the protrusion 26, and the tangled terminal 27 a is connected to the base end of the protrusion 26. It is preferable to loosen the tension of the terminal 27a by shifting to the side. The excess part of the terminal 27a is cut off.

  Here, the stator 21 is constituted by the stator core 22, the insulating layer 25, and the coil 27. As shown in FIG. 1, the stator 21 is formed on the support portion 31 of the base 30 with the projections 26 facing downward. It is fixed. Each protrusion 26 is located on the outer peripheral side of the winding portion of the coil 27 (the base end portion 23 b of the tooth 23) in the stator core 22.

  The base 30 is provided with a circuit board 32 in a fixed state. The circuit board 32 is provided with a through hole 33 for coil connection and a land part 34 (corresponding to a coil connection part) in addition to a circuit necessary for controlling the motor (see FIG. 5). As shown in FIG. 1, the terminal 27 a and the land portion 34 are electrically connected by the solder 35 in a state where the protruding portion 26 entangled with the terminal 27 a of the coil 27 is inserted into the through hole 33 of the circuit board 32. Connected to. In this case, as the conducting wire of the coil 27, the insulating layer is peeled off by the heat of the solder, such as a polyurethane copper wire formed of polyurethane, and the insulating layer of the coil 27 is removed by the heat of the solder or the soldering iron. The terminal 27 a is connected to the land portion 34 by the solder 35.

On the other hand, the rotor 37 includes a ring-shaped rotor yoke 38, a rotor magnet 39 fixed to the inner periphery of the rotor yoke 38, a synthetic resin rotating plate 40 that supports the rotor yoke 38, and the center of the rotating plate 40. And a rotating shaft 41 provided on the portion, and the rotating shaft 41 is rotatably supported by the support portion 31 of the base 30. The rotor magnet 39 is opposed to the outer peripheral surface of the tip 23a of the tooth 23 in the stator core 22 with a predetermined gap from the radial direction.
Here, each protrusion 26 in the stator 21 is formed between the winding portion of the coil 27 (the base end portion 23b of the tooth 23) and the end portion on the rotor 37 side (the outer peripheral surface of the front end portion 23a of the tooth 23) of the stator core 22. Located between.

According to the first embodiment described above, the following operational effects can be obtained.
In the stator 21, the protruding portion 26 that ties the terminal 27 a of the coil 27 is formed integrally with the insulating layer 25, so that it is different from the case where a separate metal connection terminal is insert-molded in the insulating layer 25. The strength of the protrusion 26 can be ensured, and the thickness can be reduced. Further, since it is not necessary to form a through hole for attaching the connection terminal in the stator core 22, it is possible to suppress deterioration of the motor characteristics.

  Each protrusion 26 in the stator 21 is provided between the winding portion of the coil 27 in the stator core 22 (the base end portion 23b of the tooth 23) and the end portion on the rotor 37 side (the outer peripheral surface of the tip end portion 23a of the tooth 23). Thus, the terminal 27a of the coil 27 and the circuit board 32 can be connected in a place having a relatively large space.

(Second Embodiment)
FIG. 6 shows a second embodiment of the present invention, and this second embodiment is different from the first embodiment described above in the following points. That is, the protrusion 43 provided on the insulating layer 25 is formed in a prismatic shape, in this case, a triangular prism shape.

  By forming the projection 43 in a prismatic shape (triangular prism), there is an advantage that the terminal 27a (see FIG. 3) of the coil 27 is easily entangled (wound) around the projection 43. Needless to say, the protrusion 43 may have a rectangular column shape or a hexagonal column shape as long as it has a prism shape.

(Third embodiment)
FIG. 7 shows a third embodiment of the present invention. This third embodiment differs from the second embodiment described above in the following points. That is, the surface of each protrusion 43 provided on the insulating layer 25 is covered with a metal plate 45 as a conductive member, and the terminal 27a (see FIG. 3) of the coil 27 is entangled with the surface of the metal plate 45. Like that.

  In the case of such a configuration, in particular, the terminal 27a comes into contact with the metal plate 45, and at the time of soldering, the metal plate 45 is attached to the land portion 34 of the circuit board 32 via the solder 35 (see FIG. 1). Since it is electrically connected, the electrical connectivity between the terminal 27a of the coil 27 and the land portion 34 of the circuit board 32 can be further improved.

(Fourth embodiment)
FIG. 8 shows a fourth embodiment of the present invention. This fourth embodiment differs from the above-described third embodiment in the following points. That is, a film 46 made of metal plating is provided as a conductive member on the surface of each protrusion 43 provided on the insulating layer 25.
Even with such a configuration, the same effects as those of the third embodiment can be obtained.

(Fifth embodiment)
9 and 10 show a fifth embodiment of the present invention. This fifth embodiment is different from the first to fourth embodiments described above in the following points. In other words, in the insulating layer 25, a protrusion that is positioned on the outer peripheral side of one end surface in the axial direction of the stator core 22 and protrudes more radially outward (rotor magnet 39 side) than the tip 23 a of the tooth 23. 47 is integrally formed on the insulating layer 25 by molding. The projecting portion 47 has a lateral quadrangular prism shape.

  Then, as shown in FIG. 10, the terminal 27 a of the coil 27 wound around the base end portion 23 b of each tooth 23 is wound around the protrusion 47. And the state where the projection 47 with the terminal 27a of the coil 27 is on the lower side and the lower surface of the projection 47 is in contact with the land portion 48 (corresponding to the coil connection portion) provided on the upper surface of the circuit board 32 Then, the terminal 27a of the coil 27 and the land portion 48 are electrically connected by soldering.

Also in the fifth embodiment having such a configuration, it is possible to obtain basically the same operational effects as those in the first embodiment. In addition, since the protrusion 47 protrudes not in the axial direction of the stator core 22 but in the radial direction, it is advantageous for further thinning.
Although not shown, a metal plate is provided on the surface of the protrusion 47 as a conductive member as in the third embodiment, or a metal plating film is provided as in the fourth embodiment. You may do it.

(Sixth embodiment)
FIG. 11 shows a sixth embodiment of the present invention. This sixth embodiment differs from the fifth embodiment described above in the following points. That is, in the insulating layer 25, a plurality of connecting terminal mounting portions 50 protruding in the axial direction are integrally provided by molding so as to be positioned on the outer peripheral portion side of one end surface of the stator core 22 in the axial direction. Each connection terminal attaching part 50 is provided in the site | part corresponding to the front-end | tip part 23a of each teeth 23, respectively. In this case, six pieces are provided corresponding to the teeth 23. Each connection terminal mounting portion 50 is formed with a mounting hole 51 opened in the radial direction. Then, among the six connection terminal mounting portions 50, in this case, the connection terminals 52 made of conductive metal plates are inserted into the mounting holes 51 of the four connection terminal mounting portions 50 from the radial direction, thereby connecting terminals. 52 is attached so as to protrude in the radial direction. Each connection terminal 52 has a crank shape, and in the mounted state, the distal end portion 52a side slightly protrudes to the same height as the axial end surface 50a of the connection terminal mounting portion 50 or upward in FIG.

  As in the fifth embodiment, the terminal 27a of the coil 27 wound around the base end portion 23b of each tooth 23 is entangled with the distal end portion 52a of the connection terminal 52, and the connection terminal 52 entangled with the terminal 27a. Is soldered in a state of being in contact with a land portion 48 (see FIG. 10) provided on one surface of the circuit board 32, thereby electrically connecting the terminal 27 a of the coil 27 and the land portion 48.

  According to the fifth embodiment employing such a configuration, the following operational effects can be obtained. Since the conductive connection terminal 52 attached to the connection terminal attachment portion 50 in the insulating layer 25 is attached in a form protruding toward the radial direction of the stator core 22, while securing the attachment strength of the connection terminal 52. Therefore, it becomes possible to cope with the thinning. Further, since it is not necessary to form a through hole for attaching the connection terminal in the stator core 22, it is possible to suppress deterioration of the motor characteristics.

  Furthermore, since the terminal 27a is entangled with the conductive connection terminal 52, the connection terminal 52 is electrically connected to the land portion 48 of the circuit board 32 via the solder 35 during soldering. Thus, the electrical connectivity between the terminal 27a of the coil 27 and the land portion 48 of the circuit board 32 can be improved.

(Seventh embodiment)
FIG. 12 shows a seventh embodiment of the present invention. This seventh embodiment is different from the above-described sixth embodiment in the following points. That is, in the insulating layer 25, a plurality of connecting terminal mounting portions 55 protruding in the axial direction are integrally provided by molding so as to be positioned on the outer peripheral portion side on one end face in the axial direction of the stator core 22. Each connection terminal attaching part 55 is provided in the site | part corresponding to the front-end | tip part 23a of each teeth 23, respectively. In this case, six are provided. Each connection terminal attachment portion 55 is formed with an attachment groove 56 opened in the axial direction. Then, among the six connection terminal mounting portions 55, in this case, the connection terminals 57 made of a conductive metal plate are fitted into the mounting grooves 56 of the four connection terminal mounting portions 55 from the axial direction. The terminal 57 is attached so as to protrude in the radial direction. The mounting groove 56 has a concavo-convex shape in the radial direction of the stator core 22, and a concavo-convex fitting into the concavo-convex is formed on the outer peripheral portion of the base end portion of the connection terminal 57 fitted into the mounting groove 56. By fitting the base end portion of the connection terminal 57 into the attachment groove 56, the connection terminal 57 is attached in the radial direction so as not to be detached.

Also in this case, similarly to the fifth embodiment, the terminal 27a of the coil 27 wound around the proximal end portion 23b of each tooth 23 is entangled with the distal end portion of the connection terminal 57, and the connection including the terminal 27a is entangled. By soldering the terminal 57 to a land portion 48 (see FIG. 10) provided on one surface of the circuit board 32, the terminal 27a of the coil 27 and the land portion 48 are electrically connected.
Even in such a configuration, the same effects as those of the sixth embodiment can be obtained.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be modified or expanded as follows.
The present invention is not limited to the outer rotor type, and can be applied to an inner rotor type.

The longitudinal cross-sectional view of the principal part which shows the 1st Embodiment of this invention Perspective view of the stator core with an insulating layer A perspective view of a stator in which a coil is wound around an insulating layer and a coil end is entangled with a protrusion. Perspective view of the stator with the protrusions facing downward The perspective view shown in the state where a part of rotor was omitted FIG. 2 equivalent view showing the second embodiment of the present invention FIG. 2 equivalent view showing the third embodiment of the present invention FIG. 2 equivalent view showing a fourth embodiment of the present invention FIG. 2 equivalent view showing a fifth embodiment of the present invention 1 equivalent diagram The perspective view of the state which attached the connection terminal to the insulating layer which shows the 6th Embodiment of this invention FIG. 11 equivalent diagram showing a seventh embodiment of the present invention 1 equivalent diagram showing a conventional example 2 equivalent diagram

Explanation of symbols

  In the drawing, 21 is a stator, 22 is a stator core, 23 is a tooth, 25 is an insulating layer, 26 is a projection, 27 is a coil, 27a is a terminal, 32 is a circuit board, 34 is a land (coil connection), 35 is Solder, 37 is a rotor, 43 is a protrusion, 45 is a metal plate (conductive member), 46 is a film (conductive member), 47 is a protrusion, 51 is a mounting hole, 52 is a connection terminal, 56 is a mounting groove, Reference numeral 57 denotes a connection terminal.

Claims (9)

A flat stator core,
An insulating layer made of synthetic resin provided by molding so as to cover the surface of the stator core;
A protrusion provided integrally with the insulating layer at the time of molding the insulating layer;
A coil wound on the insulating layer and having a terminal entangled with the protrusion;
A small electric motor comprising a circuit board having a coil connection portion, and a terminal of the coil entangled with the protrusion portion being electrically connected to the coil connection portion.   The small electric motor according to claim 1, wherein the protrusion protrudes in a radial direction of the stator core.   The small electric motor according to claim 1, wherein the protrusion has a prism shape.   The small electric motor according to claim 1, wherein a conductive member is provided on a surface of the protrusion.   2. The small electric motor according to claim 1, wherein the protruding portion is located between a winding portion of the coil and an end portion on the rotor side in the stator core. A flat stator core,
An insulating layer made of a synthetic resin provided to cover the surface of the stator core;
A conductive connection terminal attached to the insulating layer in a form protruding toward the radial direction of the stator core; and
A coil wound on the insulating layer and having a terminal entangled with the connection terminal;
A small electric motor comprising a circuit board having a coil connection portion and a terminal of the coil entangled with the connection terminal electrically connected to the coil connection portion. The insulating layer has a mounting hole opened in the radial direction of the stator core,
The small electric motor according to claim 6, wherein the connection terminal is attached by being inserted into the attachment hole from the radial direction. The insulating layer has a mounting groove opened in the axial direction of the stator core,
The small electric motor according to claim 6, wherein the connection terminal is attached by being fitted into the attachment groove from the axial direction.   The small electric motor according to any one of claims 6 to 8, wherein the connection terminal is disposed on a rotor side from a winding portion of the coil in the stator core.

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