JPH0227909B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a permanent magnet type stepping motor used for feeding paper in printers, driving print heads, and as a drive source for various other office equipment. .

(Constitution of Conventional Example and its Problems) A conventional stepping motor of this type is constructed as shown in FIG. In Figure 1,
Reference numeral 1 denotes a stator yoke member, which has a shallow pot shape with an open top surface, and has a circular hole in the center of the bottom surface, and a plurality of comb-like pole teeth 1a are arranged at equal intervals along the circumference of the hole. , protrudes perpendicularly from the bottom surface toward the open surface. 2 is a stator yoke member having the same shape as the stator yoke member 1, and its comb-like pole teeth 2a are the comb-like pole teeth 1 of the stator yoke member 1.
The stator yokes are butted against each other so as to be arranged alternately with gaps in the same cylindrical surface as a, thereby forming a first stator yoke. At this time, the outer peripheral edge of the stator yoke member 2 is configured to be inscribed in the outer peripheral edge of the stator yoke member 1. 3 and 4 are stator yoke members configured similarly to stator yoke members 1 and 2 to constitute a second stator yoke, and this second stator yoke is coaxially arranged with the first stator yoke shifted by one step angle. are placed on top of each other. Reference numeral 5 designates a stator coil that is wound in advance around an annular coil bobbin 6, and is held between stator yoke members 1 and 2 and 3 and 4, respectively. 7 is a permanent magnet trochanter through which a rotor shaft 8 passes through the center, and stator yoke members 1,
2, 3 and 4, respectively, comb-like pole teeth 1a, 2
It is inserted into the inside of the cylindrical part formed by a, 3a and 4a, and faces each of the comb-like pole teeth 1a, 2a, 3a and 4a with a slight gap therebetween.
A bracket 9 includes a bearing 10 that rotatably supports the rotor shaft 8, and is attached to the stator yoke members 1 and 4 located on both end surfaces of the first and second stator yokes arranged one above the other. The rotor shaft 8 is supported from above and below.

However, in the above configuration, the stator yoke members 1, 2, 3, and 4 are fixed to each other, and the stator yoke members 1 and 4 and the bracket 9 are fixed by spot welding, etc., and the number of parts is large. Therefore, the assembly is extremely complicated, and dust generated during spot welding can damage the permanent magnet rotor 7 and the comb-shaped pole teeth 1a, 2.
A, 3a, and 4a, and the permanent magnet rotor 7 has a problem that the rotation of the permanent magnet rotor 7 is obstructed by entering the small gap between the magnets 3a, 3a, and 4a.

Furthermore, the conventional stator coil 5 is shown in FIG.
As shown in FIGS. b and c, two colored copper wires 5a and 5b are simultaneously wound multiple times around an annular coil bobbin 6, and both ends of each are fixed with vinyl tape 11, and the external Each is connected to a lead wire 12 for inputting power by soldering or the like. After insulating each connection portion, they are fixed again with vinyl tape 11.

However, in the conventional stator coil 5 as described above, since the two copper wires 5a and 5b are wound at the same time, it is difficult to wind the wires in close alignment, resulting in a poor wire area ratio. Conventional stepping motors have had various drawbacks, such as the complicated winding process, which makes it difficult to mechanize the winding process, resulting in low productivity and many defects caused by manual work.

(Object of the Invention) The present invention has been made in view of the drawbacks of the above-mentioned conventional examples. It provides a ping motor.

(Structure of the Invention) In order to achieve the above object, the present invention is such that four stator yoke members are integrally molded with synthetic resin, and a coil is directly wound around the integrally molded stator yoke.

(Description of Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 3 is a cross-sectional view of an embodiment of the present invention.
Components with the same reference numerals as in FIGS. 1 and 2 indicate the same components. 13, 14, 15, and 16 are stator yoke members, and as shown in FIG. 4, a plurality of comb-like pole teeth 13 are provided on one side of an annular collar.
a, 14a, 15a and 16a protrude at equal intervals along the inner periphery at right angles to the brim. And stator yoke members 13 and 15
The comb-like pole teeth 13a and 15a of the stator yoke members 14 and 16 correspond to the comb-like pole teeth 14a of the stator yoke members 14 and 16.
and 16a, the stator yoke members 13 and 15 and the stator yoke members 14 and 16 are butted against each other so as to be arranged alternately with gaps in between within the same cylindrical surface to form first and second stator yokes. However, after arranging both of them coaxially and overlapping each other with a one-step angle shift, they are integrally molded with synthetic resin 17 to form a stator yoke. At this time, a partitioning flange 17a is placed in the center between the flange of each of the stator yoke members 13 and 14 and 15 and 16, and a bearing 10a is housed in the center of one opening of the internal cylindrical part of the stator yoke integrally molded. The bearing housing portion 17b and the bracket 17c supporting the bearing housing portion 17b are integrally formed at the same time.
A plurality of square terminal pins 18 are press-fitted and fixed into the synthetic resin part 17d on the outer periphery of the central brim of the integrally molded stator yoke, and are wound between each brim of the stator yoke. The ends of the stator coil 19 are wound and soldered. 20 is a cylindrical pot-shaped frame with a hole in the center of the bottom to fix the bearing 10b;
A collar 20a for attaching the motor protrudes from the open end, and each stator yoke member 13, 14, 15 and 16 is attached to the integrally molded stator yoke.
It is fitted onto the outside with its outer periphery inscribed.

Next, an assembly process of an embodiment of the present invention will be explained. Synthetic resin portion 1 of the central brim of the stator yoke integrally molded with synthetic resin 17 as described above.
Press fit the terminal pin 18 into the stator coil 1.
After winding and wiring 9, stator coil 19
Solder the end of the lead wire 12 to the terminal pin 18, and then connect the lead wire 12 for inputting external power to the terminal pin 1.
Solder to 8. Next, the bearing 1 is attached to the bearing housing portion 17b of the stator yoke that is integrally molded.
0a is press-fitted and fixed, one end of the rotor shaft 8 passing through the permanent magnet rotor 7 is inserted through the opening of the internal cylindrical part of the stator yoke, and the bearing housing part 1 is fixed.
The permanent magnet rotor 7 is inserted into the stator yoke by passing through the bearing 10a of the permanent magnet rotor 7b. A cylindrical pot-shaped frame 2 to which the bearing 10b is fixed
0 is externally fitted onto the stator yoke on which the permanent magnet rotor 7 is installed from its opening side, and the rotor shaft 8 is
Insert the other end into the bearing 10b. Thereafter, the opening side end of the frame 20 is caulked at a plurality of places to fix the frame 20 to the stator yoke, and the assembly process is completed.

As mentioned above, in this embodiment, the four stator yoke members 13, 14, 15 and 16 are made of synthetic resin.
7 and integrally molded with the bearing housing 17.
b and bracket 17c are formed integrally at the same time, the number of parts can be significantly reduced, and
Since the frame 20 is fixed on the stator yoke by caulking, there is no need for welding, and therefore, there is no possibility that the permanent magnet rotor 7 will malfunction due to foreign matter such as dust during welding.

Next, a stator coil winding process according to an embodiment of the present invention will be described. FIGS. 5 and 6 are a cross-sectional view of an integrally molded stator yoke according to an embodiment of the present invention before winding the stator coil, and a front view after winding the stator coil, respectively. Synthetic resin part 17d on the outer periphery of the center brim of the stator yoke
5 terminal pins 18a, 18b, 18c, 18
d and 18e are press-fitted and fixed, and the stator yoke has four stator yoke members 13, 14, 15, and 16, and two synthetic resin flanges 17a formed between them. Grooves 21a, 21b, 21c and 21d
is formed. First, connect the copper wire to the terminal pin 18a.
After wrapping multiple times, the stator groove 21 near the center
b is wound a predetermined number of times in a certain direction, and after the winding is completed, the wire is wound a plurality of times around the terminal pin 18c. Next, wind the wire in the stator groove 21a in the same direction as the stator groove 21b the same number of times, and after winding the terminal pin 18
After winding the wire a plurality of times around b, the copper wire is cut to complete the winding of the stator coil 19 in the stator grooves 21a and 21b. Then, the copper wire is wound around the terminal pin 18e a plurality of times again, and the winding is performed in the stator groove 21b and 21a in that order.
By winding wires in the order of wires c and 21d, the coil specifications as shown in FIG. 7 are obtained. After that, the copper wires wrapped by soldering and each terminal pin 18a, 18b, 1
The winding process is completed by soldering the lead wire 12 to a predetermined terminal pin 18 to establish electrical continuity with the wires 8c, 18d, and 18e and to input an external power source.

As described above, in this embodiment, when the stator yoke is integrally made of synthetic resin, the stator yoke members 13 and 14 and 15 and 1 facing each other are
By simultaneously forming flanges 17a between stator coils 6 and 6 and providing terminal pins 18 for wiring, the vinyl tape 11 for fixing and insulating the stator coils is no longer necessary, simplifying the winding work. In addition, since winding work can be performed using a single copper wire, it is extremely easy to mechanize the winding work.

In addition, in this embodiment, five terminal pins 18 are provided, and one terminal pin 18 is provided.
Although a book is used as a common terminal pin, as shown in FIG. 8, it is also possible to provide six terminal pins 18 and make the number of common terminal pins two.

(Effects of the Invention) As explained above, the present invention has the following excellent effects.

That is, first and second stator yokes;
In addition, since the housing for one of the bearings is molded at the same time, the number of parts is greatly reduced and assembly work is extremely easy.In addition, since there is no welding process, the rotation of the permanent magnet rotor due to dust generated during welding is avoided. Defects can be prevented, stable quality can be guaranteed, and winding work can be easily mechanized, leading to a significant improvement in productivity.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway view showing the configuration of a conventional stepping motor, FIGS. 2 a, b, and c are views showing the winding process of the stator coil of a conventional stepping motor, and FIG. , FIG. 4 is a partially cutaway perspective view showing the structure of a stator yoke member according to an embodiment of the present invention, and FIGS. 5 and 6 are cross-sectional views of an embodiment of the present invention. FIG. 7 is a sectional view before winding the stator coil and a front view after winding the stator coil of the integrally molded stator yoke of the example, and FIG. FIG. 8 is a diagram showing coil specifications of a stator coil according to another embodiment of the present invention. 1, 2, 3, 4, 13, 14, 15, 16...
Stator yoke member, 5, 19... Stator coil, 7... Permanent magnet rotor, 8... Rotor shaft, 1
0... Bearing, 12... Lead wire, 18... Terminal pin.

Claims (1)

[Scope of Claims] 1. A member having a plurality of comb-like pole teeth protruding at right angles to one side of an annular brim at equal intervals along its inner circumference, and another member having the same shape as said member. a first stator yoke configured to abut a pair of members against each other such that the comb-shaped pole teeth of each member are arranged alternately with gaps in the same cylindrical surface; a second stator yoke, which is composed of a pair of members similar to the first stator yoke and is disposed coaxially with the first stator yoke and overlapped with the stator yoke by one step angle;
and a stator coil sandwiched between the brim of each of the second stator yokes, and an inner surface of a cylindrical portion constituted by the comb-like pole teeth of each of the first and second stator yokes. Permanent magnet rotors facing each other with a gap, a rotor shaft passing through the center of the permanent magnet rotor, and bearings attached to the first and second stator yokes and supporting the rotor shaft. In the stepping motor, the first and second stator yokes are integrally molded with synthetic resin, and a housing for bearing the rotor shaft is provided on one end surface of the stator yoke coaxially with the cylindrical portion. A stepping motor characterized in that the portion is integrally formed during the molding. 2. The stepping motor according to claim 1, wherein the integrally molded first and second stator yokes each have a partitioning collar between the respective ribs. 3. The first and second stator yokes integrally molded include a plurality of terminal pins.
Stepping motor as described in section.