JPH07177694A - Miniature motor and connection method of terminal block therefor - Google Patents

Abstract

PURPOSE:To allow quite easy and accurate connection of a terminal block while enhancing the heat resistance of motor significantly by eliminating the soldering work of the stator winding and the feeder line. CONSTITUTION:The miniature motor comprises a stator where a stator winding 36 is wound around a bobbin, a rotor disposed in the stator, and terminal device 52 connecting between the rotor winding 36 and the feeder line electrically. And in the terminal device 52, wherein the terminal components 60 are connected to the stator winding by electrical conductor with a resistance welding and the terminal components 60 also are connected to the feeder line with resistance welding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary type small motor such as a stepping motor, and more particularly to a terminal device thereof and a connecting method thereof.

[0002]

2. Description of the Related Art Rotary small motors are widely used in various fields such as precision equipment such as small cameras, audio / visual equipment such as VTRs, and electrical equipment for automobiles. A stepping motor, which is a type of small motor, is widely used as a drive source for various electronic devices such as a copying machine. The stepping motor includes a stator having a stator winding wound around a bobbin, a rotor disposed inside the stator, and a terminal device for electrically connecting the stator winding and a power supply line. It has and.

FIG. 16 is a perspective view of a bobbin with a winding including a conventional terminal device. As shown, the bobbin 1 is integrally formed with the block portion 2 by extrusion molding, and a plurality of (three) pin terminals 3 are press-fitted and fixed to the block portion 2. Bobbin 1
The stator winding 4 wound around is fixed to the pin terminal 3, and the stator winding 4 and the pin terminal 3 are electrically connected by the solder 5.

FIG. 17 is a perspective view showing a state in which a power feed line is connected to the bobbin 10 with the winding shown in FIG. As shown in the figure, the pin terminals 3 are fixed to the printed circuit board 6 by soldering, and the ends of the power supply lines 7 are soldered to the printed circuit board 6. The copper terminals 8 provided on the printed circuit board 6 electrically connect the pin terminals 3 and the power supply line 7, and thus an electric current is supplied from the external power source to the stator winding 4 through the power supply line 7. The stator of the stepping motor is configured by combining two bobbins 10 with windings provided with the terminal device 9 having such a configuration.

[0005]

In the conventional terminal device 9 as described above, the stator winding 4 and each pin terminal 3, the pin terminal 3 and the printed circuit board 6, and the printed circuit board 6 and the power supply line 7 are connected. Since each of them was soldered by hand, the connecting work was very complicated and it was difficult to automate the connecting work. Further, if the space between adjacent solders is narrow, there is a risk of short-circuiting with the adjacent solder, so a high level of technology is required for the soldering work, and defective products may occur due to the short circuit.

In order to prevent this, if the space between the adjacent solders is widened, the terminal device 9 becomes large in size, and in order to mount this terminal device 9, it is necessary to make a large cutout in the motor casing. If the notch of the casing becomes large, it interferes with the construction of the magnetic circuit of the motor, which is disadvantageous in terms of the magnetic circuit. In addition, the casing is likely to be distorted, which may reduce the roundness of the casing.

Further, when the stator winding 4 is a wire coated with an insulating film having a high heat resistance temperature (for example, 130 ° C. or higher) such as polyester wire, the heat of the soldering iron does not sufficiently destroy the insulating film. Therefore, there is a possibility that a poor conduction may occur between the polyester wire 4 and the pin terminal 3. In order to prevent this conduction failure, conventionally, the solder was removed by chemically dissolving the insulating coating on the connection part with a solvent or the like before the soldering operation. This is an obstacle to automating the connection work of the terminal device 9.

The power supply line 7 may be directly attached to the pin terminal 3 by soldering without using the printed circuit board 6, but since the connecting portion is weak in strength and the soldering work is difficult, it is generally performed as described above. Through the printed circuit board 6 to the pin terminal 3
And the power supply line 7 were connected. In this way, although the strength of the connecting portion is improved, there is a problem that the number of parts is increased and the connecting man-hour is increased.

Of the small motors, the stepping motor, in particular, has a large amount of heat generated by the motor itself, so that the heat resistant temperature of the stator winding 4 is the allowable heat resistant temperature of the stepping motor. Therefore, if the stator winding 4 having a high heat-resistant temperature can be used, the allowable heat-resistant temperature of the motor can be increased and the heat resistance of the motor can be improved. Due to the problems, the heat resistance of the stepping motor was naturally limited. It should be noted that since harmful gas and odor are generated during soldering work, it is necessary to take measures regarding the working environment, and solder or solder paste may scatter during the soldering work to reduce the yield of products. .

Japanese Unexamined Patent Publication No. 59-194658 and Japanese Unexamined Patent Publication No. 61-121737 also disclose a structure relating to a terminal device of a motor, but both require soldering work for connecting the stator windings. In addition, there is a problem that the number of parts is large and the terminal device is bulky and cannot be made compact.

The present invention has been made in order to solve the above problems, and it is possible to connect the terminal device extremely easily and accurately without the need for soldering work to the stator winding and the power supply line, and to improve the heat resistance of the motor. It is an object of the present invention to provide a small-sized motor capable of significantly improving the performance and a method for connecting a terminal device of the small-sized motor.

[0012]

In order to achieve the above object, a small motor according to the present invention comprises a stator having a stator winding wound around a winding frame, and a stator disposed inside the stator. And a terminal device for electrically connecting the stator winding and the power supply line, and the terminal device is formed of a conductor and connected to the stator winding by electric resistance welding means. In addition, it is provided with a terminal member connected to the power supply line by at least one of the tightening means and the electric resistance welding means.

Further, the terminal member includes a support portion which is inserted into an engaging hole of the winding frame around which the stator winding is wound, and J.
A hook portion that is hooked to the stator winding, is deformed by the electric resistance welding means, and is fixed to the stator winding to conduct electricity, and the feeder wire is J-shaped. It is preferable to have a power feeding line holding portion that holds the power feeding line and that is electrically connected to the power feeding line, and be integrally bent.

Also, in the method of connecting a terminal device according to the present invention, a stator winding is wound around a winding frame of a stator, a rotor is disposed inside the stator, and the terminal device fixes the stator winding. In a method of connecting a terminal device provided in a small motor for electrically connecting a child winding and a power supply line, a terminal member of the terminal device is formed of a conductor, and the stator winding is electrically resistance welded to the terminal member. And the power supply line is connected to the terminal member by at least one of tightening and electric resistance welding.

[0015]

According to the present invention, when a large amount of current is applied to the terminal member to which the stator winding is hooked for a moment, the terminal member acts as a resistor to generate heat and the stator winding and the terminal The contact portion with the member also generates heat due to the contact resistance. At this time, the insulating film of the stator winding in the contact portion is also completely removed by melting at a high temperature, and the stator winding is fixed and conductive in direct contact with the terminal member.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A small motor according to the present invention will be described below with reference to FIGS. 1 to 15 by taking a stepping motor used as a drive source of an electronic device such as a copying machine, a printer, a facsimile and a typewriter as an example. .

(First Embodiment) FIGS. 1 to 9 are views showing a first embodiment of the present invention. FIG. 1 is an external view of a stepping motor, FIG. 2 is a sectional view of the motor of FIG. 1, and FIG. FIG. 3 is a perspective view of the stator core shown in FIG. 2. The illustrated stepping motor 20 is a PM-type (Permanent Magnet Type) small motor, and has a structure in which a rotor made of a permanent magnet is attracted and rotated by an electromagnetic force generated by a stator winding.

As shown in FIGS. 1 and 2, the casing 2
A stator 22 is mounted inside the stator 1, and a rotor 23 disposed inside the stator 22 is provided inside the casing 21. The rotary shaft 24 fixed to the center of the rotor 23 in the axial direction is rotatably supported by bearing members 25 and 26 provided in the casing 21.

The casing 21 is formed of a housing 27 formed of a ferromagnetic metal material in the shape of a hollow cylinder having a bottom, and the same metal material as the housing 27, and is caulked or welded to the opening 28 of the housing 27. And a lid member 29 fixed by, for example. Lid member 29
The bearing member 26 is fixed in the circular mounting recess 30 formed in the center of the housing 27, and the bearing member 25 is fixed in the mounting hole 32 formed in the center of the side surface 31 of the housing 27. The bearing members 25, 26 are oilless type bearings formed of powder sintered metal or powder sintered alloy impregnated with a synthetic resin or lubricating oil having lubricity.

The stator 22 has an inner surface 27 of the housing 27.
It is composed of a first block 33 and a second block 34 which are fixed to a, are juxtaposed in the axial direction, and are arranged back to back. A stator winding (magnet wire) 36 is wound around an annular bobbin 35 as a winding frame of the first block 33 to form an annular excitation coil 37. The bobbin 35 is integrally molded with an insulating material such as an insulating synthetic resin such as polybutylene terephthalate (PBT).

The stator core 38 supporting the bobbin 35 is made of a ferromagnetic metal material, and as shown in FIG. 3, an annular disc portion 39 and an inner peripheral edge 40 of the disc portion 39 extending from the central axis. A plurality of comb-shaped magnetic poles 41 are provided so as to project in parallel in one direction and are uniformly arranged along the inner peripheral edge 40. A concave portion 43 is formed on the outer peripheral portion of the disc portion 39. As shown in FIG. 2, the stator winding 36 is attached to the bobbin 35.
The first block 33 is configured by fixing the bobbin 42 with windings wound on the stator core 38.
The second adjacent to the first block 33 and fixed back to back
The block 34 also has the same configuration as the first block 33.

On the outer peripheral surface 50 of the housing 27, a cutout portion 51 that is open to the opening 28 side is formed, and a terminal device 52 is arranged in the cutout portion 51. Terminal device 52
Is for electrically connecting the stator winding 36 and a power supply line 53 that is connected to an external power source (not shown) and supplies a current to the stator winding 36.

The terminal device 52 projects outward from the housing outer peripheral surface 50 through the notch 51, but the lid member 29
The cover portion 54 is integrally bent to form the cover portion 54
Covers the opening 55 of the cutout 51. As a result, the area of the open portion 55 due to the cutout portion 51 is made as small as possible to prevent it from interfering with the configuration of the magnetic circuit, and also prevent foreign matter such as dust from entering the inside of the motor 20 from the open portion 55. There is. Further, by disposing the cover portion 54 on the lid member 29, the motor 20 can be disassembled and assembled.

In the first block 33, the housing 27, the disk portion 39 of the stator core 38 and the comb-shaped magnetic pole 41 form a first magnetic circuit through which the magnetic flux generated by the exciting coil 37 of the first block 33 passes. It is formed. On the other hand, also in the second block 34, the housing 27,
The lid member 29, the comb-shaped magnetic pole 41 of the stator core 38, and the disc portion 39 form a second magnetic circuit through which the magnetic flux generated by the exciting coil 37 of the second block 34 passes.

The rotor 23, which is disposed radially inward of the stator core 38, is a cylindrical type formed of permanent magnets in which a plurality of magnetic poles extending in the direction parallel to the rotation center line are arranged in the circumferential direction. A rotor magnet 56 is provided. The rotor magnet 56 is obtained by uniformly performing multi-pole magnetization by alternately arranging N poles and S poles on a cylindrical outer peripheral surface, and a polar anisotropic or radial anisotropic ferrite magnet is used. There is.

In the motor 20 having the above-mentioned structure, the stator windings 36 forming the exciting coils 37 of the first and second blocks 33 and 34 via the power supply line 53 and the terminal device 52.
When currents whose phases are shifted from each other are applied to each exciting coil 37,
Are alternately excited and magnetic forces are alternately generated in the first and second magnetic circuits. The position of the comb-shaped magnetic pole 41 of each stator core 38, which is excited by each exciting coil 37, is also shifted by a predetermined step angle. Then, the excited comb-teeth magnetic pole 41 attracts the rotor magnet 56, and the rotor 23 rotates by a predetermined step angle. As a result, an electronic device such as a copying machine can be driven via the rotating shaft 24 that rotates.

Next, the structure of the terminal device 52 will be described with reference to FIGS. 4 is an exploded perspective view of the terminal device 52 of the motor 20 of FIG. 1, and FIG.
2 is a perspective view, FIG. 6 is a front view showing the bobbin 42 with a winding including the terminal device 52, and FIG. 7 is a sectional view taken along line VII-VII of FIG. 8 and 9 show the terminal device 5 by means of electric resistance welding means.
FIG. 8 is a view showing a method of assembling 2, wherein FIG. 8 is a front sectional view and FIG.
Is a plan view. The terminal device 52 includes a terminal member 60 formed of a conductor such as a beryllium copper plate material.
The terminal member 60 is an electric resistance welding means 61 (FIGS. 8 and 9).
Are connected to the stator winding 36 and the power supply line 53, respectively.

In the method of connecting the terminal device 52 of the stepping motor 20 as a small motor according to the present invention, the stator winding 36 is wound around the bobbin 35 as the winding frame of the stator 22, and the inside of the stator 22 is wound. In the method of connecting a terminal device provided in a small motor in which the rotor 23 is disposed and the stator winding 36 and the power supply line 53 are electrically connected by the terminal device, the terminal member 60 of the terminal device 52 is made of a conductor. The stator winding 36 is connected to the terminal member 60 by electric resistance welding, and the feeder wire 53 is connected to the terminal member 60 by tightening and / or electric resistance welding. In the first embodiment, the terminal member 60 and the power supply line 53
And are connected by electric resistance welding.

Since the first and second blocks 33 and 34 provided with the terminal device 52 have the same structure, only one block will be described. As shown in FIG. 4, on the outer peripheral surface 62 of the bobbin 35, a substantially rectangular block portion 63 is integrally projectingly molded outward. A part of the block portion 63 is fitted into the recess 43 (FIG. 3) of the stator core 38 to fit the bobbin 3
5 and the stator core 38 are positioned in the circumferential direction. A plurality of (for example, three) bottomed engagement holes 65 are formed in the end surface 64 of the block portion 63, and a plurality of (for example, three) terminal members 60 are respectively inserted into the engagement holes 65 by press fitting. It is supposed to be done.

The three engaging holes 65 are arranged in a row in the longitudinal direction of the end surface 64 of the block portion, and are formed at positions displaced toward one edge portion 64a. As a result, the three terminal members 60 inserted into the respective engagement holes 65, as shown in FIG.
The bobbin 35 is arranged at a position eccentric to the right in the drawing from the center position G of the bobbin 35.

Each of the terminal members 60 may be attached to the engaging hole 65 one by one, but in order to improve the assembly work efficiency, one sheet of beryllium copper is punched out and then bent to form three terminals. It is preferable that the members 60 are integrally formed in a continuous state, and a cut line is engraved at the root of each terminal member 60.

Then, after each terminal member 60 integrated with the copper plate material is inserted into each engagement hole 65 to temporarily fix each terminal member 60 to the block portion 63, unnecessary portions of the copper plate material are bent. Then, the unnecessary part is broken off at the score line and removed. Then, if each terminal member 60 is press-fitted into the block portion 63 at the same time at three places, all three terminal members 60 can be assembled into the block portion 63 at one time, and the assembling time can be shortened.

The terminal member 60 is integrally formed in a direction perpendicular to the support portion 70, which is inserted into the engagement hole 65 of the bobbin 35 as a winding frame around which the stator winding 36 is wound, and the support portion 70. And a hook portion 67 that is J-shaped and is integral with the support portion 70 via the base portion 66, and is integrally formed with the support portion 70 that is J-shaped through the base portion 66. And has a power supply line holding portion 71 that holds the power supply line 53 and is electrically connected to the power supply line 53, and is integrally bent and formed.

Hook portion 67 to which the stator winding 36 is hooked
Is deformed by the electric resistance welding means 61 (FIGS. 8 and 9), and is fixed to the stator winding 36 so as to conduct. The power supply line holding portion 71 is the hook portion 6
It is formed by bending a protruding piece of the base portion 66 continuous with 7, and is positioned laterally (leftward in FIG. 6) with respect to the hook portion 67 as shown in FIG.

Projecting pieces 72 are formed on both side edges of the supporting portion 70 to prevent them from coming off. When the supporting portion 70 is pressed into the engaging hole 65, it is softer than the metal terminal member 60. The bobbin 35 made of synthetic resin is deformed and the projection piece 7 is deformed.
2 is locked to the inner wall of the engagement hole 65, and the terminal member 60 is firmly fixed to the block portion 63. When a pair of bobbins 35 having the terminal device 52 having such a structure are assembled back to back, as shown in FIG.
0s are arranged alternately in a zigzag pattern, and the adjacent terminal member 60
The power supply line 53 can be connected without disturbing.

As shown in FIGS. 8 and 9, the electric resistance welding means 61 is made of an insulating material, and has a support base 77 for supporting the back surface 76 of the bobbin 42 with windings and the back surface 68 of the block 63, An electrode (for example, a + electrode) 78 arranged to face the hook portion 67 of each terminal member 60.
And an electrode 80 having a pole (for example, a negative pole) opposite to that of the electrode 78 and electrically connected to the power supply line holding portion 71 so as to be able to contact and separate. The electrode 78 is worn out gradually as it is used, and therefore it is preferable to replace it periodically. The electrode 78 has a hook portion 67 by an electrode support portion 79.
On the other hand, as shown by an arrow C, it moves back and forth. Contrary to the above description, the electrode 78 may be the negative electrode and the electrode 80 may be the positive electrode.

When the stator winding 36 and the power supply line 53 are respectively connected to the terminal member 60, the stator winding 36 is wound around the empty bobbin 35 as shown in FIGS. Connect each end of the stator winding 36 to the terminal member 6 at a predetermined position.
It is wound around the hook portion 67 of 0 several times and hooked. At this time, it is not necessary to remove the insulating coating of the stator winding 36 with a solvent or the like in advance. Then, the back surfaces 76 and 68 of the winding bobbin 42 are brought into contact with the support base 77 so that the winding bobbin 4
Position 2. On the other hand, the electrode 80 is connected to the feeder line holding unit 7.
The upper surface 69 of No. 1 is contacted with the contact point D in advance.

Next, as shown in FIG. 4, the core wire 81 of the end 75 from which the insulating coating 74 of the power supply line 53 has been removed in advance is J
It is inserted and attached to the inside of the character-shaped power supply line holding portion 71. Desirably, thereafter, the upper surface 69 of the holding portion is pressed by tightening means such as a tightening tool 83 having a predetermined shape, and the core wire 81 is tightened by the power supply wire holding portion 71. Since the power supply wire holding portion 71 is J-shaped, the work of inserting the core wire 81 is easy,
Further, even when the core wire 81 is tightened, the power supply line holding portion 71 can be held in close contact with substantially the entire circumference of the core wire 81.

Next, as shown in FIGS. 8 and 9, the electrode support 79 is driven to move the three electrodes 78 simultaneously in the right direction in each figure to bring them into contact with the contact point E of the hook 67. Further, the hook portion 67 is pressed to crush the entire hook portion 67 and deform it into a plate shape (see FIG. 5). At this time, at the moment when the electrode 78 contacts the contact point E, the electrodes 78, 8
0 is turned on for a short time to flow a large current through the terminal member 60. Then, a current flows from the electrode 78 to the contact point E, the hook portion 67, the base portion 66, and the power supply line holding portion 71 in this order, and instantaneously flows from the contact point D on the upper surface 69 to the electrode 80.

The terminal member 60 is made of a conductive material such as beryllium copper, but when a large amount of current instantaneously flows, the terminal member 60 becomes a resistance and high heat is generated. On the other hand, the stator winding 36 is wound around the hook portion 67. However, due to the heat generated by the hook portion 67 itself becoming a resistance and the contact resistance of the contact portion between the stator winding 36 and the hook portion 67. Due to the heat generation, the stator winding 36 at the contact portion also becomes hot. As a result, the insulating coating of the stator winding 36 is heated to a temperature higher than the melting temperature and melted and completely removed, and the stator winding 36 and the hook portion 67 are in direct contact with each other and firmly fixed to each other for reliable conduction.

Although the stator winding 36 is electrically connected to the hook portion 67 without deforming the hook portion 67, if the hook portion 67 is pressed by the electrode 78, as shown in FIG. The stator winding 36 is more firmly held by 67, and the connection strength is increased.

Further, similarly to this, the core wire 81 of the feeder line 53
Is fastened to the inside of the power supply line holding portion 71, but heat is generated due to the power supply line holding portion 71 itself becoming a resistance, and the core wire 8
The contact portion locally melts due to the heat generated by the contact resistance of the contact portion between 1 and the power supply line holding portion 71. As a result, the core wire 81 is fixed to the power supply line holding portion 71 and is surely conducted.

The terminal member 60 and the core wire 8 of the feeder line 53
The connection with 1 may be made only by tightening or only by electric resistance welding, but it is preferable to make connection by both tightening and electric resistance welding as in this embodiment, because the strength of the contact portion increases. When the electric power supply line 53 is connected only by tightening without using electric resistance welding, one electrode 80 may be brought into contact with the base 66 at the contact point D ₁ (FIG. 5) instead of the contact point D. . With this configuration, the electric current flows in the order of the electrode 78, the contact point E, the hook portion 67, and the base portion 66, and then flows from the contact point D ₁ to the electrode 80. Resistance welding can be performed.

An example of conditions for electric resistance welding when the frequency is 50 Hz is shown below. (1) Voltage: about 2V to about 4V (2) Frequency: 50Hz (3) Inclination angle θ of the tip 78a of the electrode 78: 2 ° to 10 ° (4) Pressing force of the electrode 78 against the hook portion 67: about 6 0.5 kgf (5) Welding time: about 5 to about 8 cycles (6) Current: about 1200 A to about 1500 A (7) Time of applying current: about 0.08 seconds to about 0.1
3 seconds

(Second Embodiment) FIG. 10 is a view showing a second embodiment of the present invention and is a perspective view of a terminal device after electric resistance welding. As shown in the figure, the terminal member 60a of the terminal device 52a of the present embodiment has a length of the base portion 66a which is equal to that of the base portion 6 of the first embodiment.
6 (FIGS. 4 and 5) to make the power feeding line 53 held by the power feeding line holding portion 71 closer to the hook portion 67 side, but the configuration of the other portions is similar to that of the first embodiment. .

With this arrangement, the terminal member 60a can be downsized, the distance between the terminal members 60a can be increased, and the power supply line 53 to the terminal member 60a can be increased.
The work of inserting and tightening is easy. Further, the pitch between the terminal members 60a can be reduced to reduce the size of the terminal device 52a.

(Third Embodiment) FIG. 11 is a view showing a third embodiment of the present invention and is a perspective view of a terminal device after electric resistance welding. As shown in the figure, in the terminal member 60b of the terminal device 52b of the present embodiment, the power feed line holding portion 71b that holds the power feed line 53 and the first holding portion 84 that holds the outer peripheral surface of the insulating coating 74 by tightening. , And a second holding portion 85 which is arranged in parallel with the hook portion 67 and holds and connects the core wire 81. The first and second holding portions 84 and 85 are integrally formed by bending a part of the base portion 66b. The configuration of the other parts is the same as that of the first embodiment.

With this configuration, one power supply line 53
Can be held at two points by the first and second holding portions 84 and 85, so that the connection strength is improved. Further, since the power supply line 53 is attached to the terminal member 60b in a bent state,
Even if the power supply line 53 is pulled by an external force, it does not easily come off. The position where one of the electrodes 80 is brought into contact is the contact point D on the second holding portion 85 or the contact point D ₁ on the base 66b.
Either of them may be used.

(Fourth Embodiment) FIG. 12 is a view showing a fourth embodiment of the present invention and is a perspective view of a terminal device after electric resistance welding. As shown in the figure, in the terminal member 60c of the terminal device 52c of the present embodiment, the power feed line holding portion 71c that holds the power feed line 53 and the first holding portion 84c that holds the outer peripheral surface of the insulating coating film 74 by tightening. The second holding portion 85c is provided in the middle of the hook portion 67c extending downward in the figure and holds and connects the core wire 81.

The first and second holding portions 84c and 85c are integrally formed by bending a part of the base portion 66c. According to this structure, since the feeder line 53 can be held at two points in a bent state, the same operational effect as that of the third embodiment can be obtained. Since the second holding portion 85c is adjacent to the hook portion 67c, the contact point D on the second holding portion 85c is preferable as the position where one of the electrodes 80 is brought into contact. Further, since the terminal member 60c of the present embodiment is formed in a vertically long shape, it is possible to increase the distance between the adjacent terminal members 60c, and to insert or fasten the power supply line 53 to the terminal member 60c. Work becomes easier.

(Fifth Embodiment) FIG. 13 is a view showing a fifth embodiment of the present invention and is a perspective view of a terminal device after electric resistance welding. As shown in the figure, the terminal device 52d of this embodiment may use any of the terminal members of the first to fourth embodiments, but the terminal member 60 of the first embodiment is used. In this embodiment, the end 75 of the power supply line 53 is inserted into the power supply line holder 71 without removing the insulating coating 74 of the power supply line 53. Then, the electrode 78 (FIGS. 8 and 9) is brought into contact with the contact point E of the hook portion 67, and the electrode 80 is brought into contact with the contact point D of the power supply wire holding portion 71 to cause the terminal member 60 to have a larger current than that in each of the embodiments. Shed.

Then, the insulating coating of the stator winding 36 and the insulating coating 74 of the power supply line 53 are heated to a temperature higher than the melting temperature and melted to be completely removed. As a result, the stator winding 36
And the hook portion 67 come into direct contact with each other and are fixed to each other to ensure electrical continuity. On the other hand, since the insulating coating 74 of the power supply line 53 has a large thickness, a slight gap may occur between the exposed core wire 81 and the power supply line holding portion 71. In such a case, if the power supply line holding portion 71 is tightened by using the tightening tool 83 (FIG. 4) or the like, the power supply line holding portion 71 and the core wire 81 are brought into direct contact with each other to establish conduction. By doing so, the work of removing the insulating coating 74 is not required, and the connection work is further simplified.

(Sixth Embodiment) FIGS. 14 and 15 are views showing a sixth embodiment of the present invention. FIG. 14 is a perspective view showing a part of a terminal device before electric resistance welding, and FIG. 15 is an electric resistance. It is a perspective view which shows a part of terminal device after welding. As shown, in the terminal device 52e, the block portion 63 of the bobbin 35 is provided.
In e, a pair of concave portions 93 is formed on the side surface 92 on the side where the hook portion 67 is located. Each recess 93 has a hook 67
The length H from the end surface 64 of the block portion is longer than the length L of the hook portion 67.

The electrode 78 of the electric resistance welding means 61 (see FIG. 8,
In FIG. 9), the hook portion 67 is pressed by a large force and
When deformed as shown in FIG. 5, the side surface 92 is also crushed by the back surface of the hook portion 67 having a high temperature. However, since the concave portions 93 are formed on both sides of the hook portion 67, the resin meat 94 on the crushed portion of the side surface 92 moves into the concave portions 93 on both sides. Therefore, it is possible to prevent the crushed resin meat 94 from rising on the surface of the side surface 92.

There are various types of stator windings 36, but typical windings are shown below. (1) Polyurethane wire Enamel wire baked with polyurethane resin paint,
Direct soldering is possible without peeling off the insulating coating. Heat resistance temperature: 120 ° C. (2) Polyester wire Enamel wire baked with modified polyester resin paint. Normally, the insulating coating does not peel off at the soldering iron tip temperature, and it is necessary to peel it off with a solvent or the like. Heat resistance temperature: 130 ° C (3) Class H electric wire An enamel wire baked with an imide resin or amide resin paint, and the insulating coating does not peel at all at the soldering tip temperature, and must be peeled off with a solvent or the like. Heat resistant temperature: 180 ℃

Conventionally, when the polyurethane wire is used as the stator winding 36, the soldering work can be directly carried out. However, for the polyester wire and the H-class wire, the work of peeling the insulating coating in advance with a solvent or the like can be carried out. Was needed. On the other hand, in the present invention, the stator winding 36 is connected to the terminal members 60, 60a, 60b, 6 by electric resistance welding instead of soldering.
Since it is connected to 0c, even if it is a polyester wire or a class H electric wire, if the welding conditions such as the electric quantity and the energizing time of electric resistance welding are adjusted so that it is higher than the melting temperature of the insulating coating, it becomes high temperature. The insulating film thus peeled off easily and the stator winding 36 comes into direct contact with the hook portion 67 to conduct electricity.

As described above, according to the present invention, the soldering work for connecting the stator winding 36 and the power supply line 53 to the terminal member 60 and the work for removing the insulating coating film with a solvent are not required, which is extremely simple and easy. The terminal device can be connected accurately. Moreover, since a polyester wire having a heat resistant temperature of 130 ° C. or a class H electric wire having a heat resistant temperature of 180 ° C. can be used for the stator winding 36, the heat resistant temperature of the motor is 130 ° C. to 1 ° C.
It can be as high as 80 ° C. or higher.

Further, since parts such as a printed board which are large and bulky in the past are not required, the number of parts can be reduced and the terminal device can be made compact. Further, since the stator windings 36 can be connected to a plurality of terminal members (three in this embodiment) at the same time, the working time of the wiring is greatly reduced and the wiring work can be automated easily.

Further, since the soldering work of the stator winding 36 and the power supply line 53 is eliminated, a short circuit due to the soldering of the connection portion does not occur, so that the pitch between the terminals is reduced and the terminal device is made compact. It is also possible to prevent the generation of defective products due to soldering. Further, no harmful gas or odor is generated by the soldering work, and the working environment is improved. Further, the solder and the solder paste do not scatter during the soldering work, and the yield of the product is improved.

Although each of the above embodiments has described the PM type stepping motor, the present invention is not limited to the VR type (Variab).
le Reluctance Type) and HB type (Hybrid Type). Furthermore, the present invention can be applied to rotary small motors other than stepping motors. In the drawings, the same reference numerals indicate the same or corresponding parts.

[0061]

Since the present invention is constructed as described above, the terminal device can be connected very easily and accurately without the need for soldering work with the stator winding and the power supply line, and the heat resistance of the motor can be greatly improved. Can be improved.

[Brief description of drawings]

1 to 9 are views showing a first embodiment of the present invention, and FIG. 1 is an external view of a stepping motor.

2 is a cross-sectional view of the motor of FIG.

FIG. 3 is a perspective view of the stator core shown in FIG.

4 is an assembly exploded perspective view showing a terminal device of the motor of FIG. 1. FIG.

FIG. 5 is a perspective view of a terminal device.

FIG. 6 is a front view showing a bobbin with a winding including a terminal device.

7 is a sectional view taken along line VII-VII of FIG.

8 and 9 are views showing a method of assembling a terminal device by electric resistance welding means, and FIG. 8 is a front sectional view.

9 is a plan view of FIG. 8. FIG.

FIG. 10 is a perspective view of the terminal device after electric resistance welding according to the second embodiment of the present invention.

FIG. 11 is a perspective view of the terminal device after electric resistance welding according to the third embodiment of the present invention.

FIG. 12 is a perspective view of a terminal device after electric resistance welding according to a fourth embodiment of the present invention.

FIG. 13 is a perspective view of the terminal device after electric resistance welding according to the fifth embodiment of the present invention.

14 and 15 are views showing a sixth embodiment of the present invention, and FIG. 14 is a perspective view showing a part of a terminal device before electric resistance welding.

FIG. 15 is a perspective view showing a part of the terminal device after electric resistance welding.

FIG. 16 is a perspective view of a winding bobbin including a conventional terminal device.

FIG. 17 is a perspective view showing a state in which a power feed line is connected to the winding bobbin of FIG. 16.

[Explanation of symbols]

20 Stepping Motor (Small Motor) 22 Stator 23 Rotor 35 Bobbin (Reel) 36 Stator Winding 52, 52a, 52b, 52c, 52d, 52e Terminal Device 53 Power Supply Line 60, 60a, 60b, 60c Terminal Member 61 Electric resistance welding means 65 Engagement holes 67, 67c Hook part 70 Support parts 71, 71b, 71c Power supply wire holding part 83 Tightening tool (tightening means)

Claims (3)

[Claims] 1. A stator (22) having a stator winding (36) wound around a bobbin (35), a rotor (23) disposed inside the stator, and the stator. Sub winding and feeder (5
3) The terminal device (52, 52a, 5) for electrically connecting with
2b, 52c, 52d, 52e), and this terminal device is formed of a conductor and is connected to the stator winding by electric resistance welding means (61), as well as tightening means (83) and electric resistance welding means. A small motor comprising a terminal member (60, 60a, 60b, 60c) connected to the power supply line by at least one of the above. 2. The terminal member has a support portion (70) inserted into an engaging hole (65) of the winding frame around which the stator winding is wound, and a J-shaped fixing portion. The hook portions (67, 67) are engaged with the child winding, are deformed by the electric resistance welding means, and are fixed to the stator winding to conduct electricity.
c) and a power supply line holding portion (71, 71b, 71c) which is in the shape of a J and holds the power supply line and is electrically connected to the power supply line. The small motor according to claim 1, which is characterized in that. 3. A stator winding (36) is wound around a bobbin (35) of the stator (22), and a rotor (23) is arranged inside the stator, and the rotor is arranged by the terminal device. In a method for connecting terminal devices provided in a small motor for electrically connecting a stator winding and a power supply line (53), the terminal devices (52, 52a, 52b, 52c, 52d, 5
2e) the terminal member (60, 60a, 60b, 60c) is formed of a conductor, the stator winding is connected to the terminal member by electric resistance welding, and the power supply line is tightened and the electric resistance is connected to the terminal member. A method for connecting a terminal device for a small motor, characterized in that connection is made by at least one of welding.