JPH025671Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a small motor structure in which a core set using an annular core having a comb-shaped pole in the center is sandwiched between cup-shaped cases. .

[Prior art]

The structure of the core assembly and case of a conventional PM type stepping motor will be explained with reference to FIGS. 15 and 16.

Dowels 1g, 2g and holes 1h, 2 are attached to the annular cores 1, 2 having comb-like poles 1e, 2e in the center.
h is provided. The cores 1 and 2 are aligned so that the poles 1e and 2e protrude in opposite directions, and are press-fitted or caulked into the dowel and hole, thereby joining the cores 1 and 2 to form a core set. configured. Cases 3 and 4 are
Each has a comb-shaped pole 3c, 4c in the center, and the pole 3c, 4c connects the pole 1e, 2e from the protruding side of the pole 1e, 2e of the core group.
The cases 3, 4 and the cores 1, 2 are arranged so that they are alternately combined with the cases 3, 4, and the outer peripheries of the cores 1i, 2i are lightly press-fitted inside the cup-shaped cases 3, 4. It is fitted. Further, the opening sides of the cases 3 and 4 are aligned, and multiple joints on the outer peripheries of the cases 3 and 4 are plasma welded (plasma welded portions 14).
The four were fixed together. As shown in FIG. 15, a coil bobbin 6 around which an excitation coil 5 is wound is fitted to the outer periphery of the pole, and bearings 11, 11 are fixed to both sides of the cases 3, 4. A mounting plate 7 and a side plate 8 were fixed to the cases 3 and 4.

As mentioned above, when cases 3 and 4 are fixed by plasma welding, the area around the welds changes color due to the high temperature, making it unsightly, and the welds need to be covered with expensive nickel plating or labels, which increases the number of man-hours. There is a risk that the case may become distorted due to the heat of welding, or that resin parts such as the coil bobbin may become deformed. Furthermore, plasma welding requires argon gas as a fuel during the assembly process, which requires large-scale equipment, and has the disadvantage that argon gas is present during the assembly process, giving workers a sense of anxiety. Furthermore, once a product has been welded, it becomes impossible to disassemble it without cutting the case, and defective products cannot be repaired, resulting in large production losses.

[Purpose of invention]

In view of the above-mentioned drawbacks, the present invention solves the problem of high temperatures caused by welding by fixing the case by locking the core and the opposite sides of the case together, thereby solving the problem caused by the high temperature of welding. The purpose is to propose a motor structure.

[Structure of the idea]

In the present invention, steps and notches are formed on the peripheral edges of two annular cores having comb-shaped poles facing the rotor in the center, and the poles of the two cores are arranged in opposite directions. The stepped portion of one core and the cutout portion of the other core are fitted together to form a core assembly, and the core assembly is sandwiched between two cup-shaped cases, and the stepped portion and the notched portion of the other core are fitted together to form a core assembly. The outer side of the case and the stepped portion are engaged at the fitting position with the notch.

〔Example〕

Hereinafter, the structure of the small motor of the present invention will be explained with reference to the illustrated embodiments. In FIG. 1 to FIG. 3, the peripheral edges of the two annular cores 1 and 2 have stepped portions 1a and 2a.
and notches 1b and 2b are formed, and the cores are aligned so that the poles 1e and 2e respectively protrude to opposite sides. At this time, the stepped portion 1 of one core 1
a is connected to the notch 2b of the other core 2, and the stepped portion 2a of the other core 2 is connected to the notch 1 of one core 1.
b. In addition, there are 1 dowels on cores 1 and 2.
d, 2d and holes 1c, 2c are formed, and the dowel 1d of one core 1 is connected to the hole 2c of the other core 2.
, the dowel 2d of the other core 2 is connected to the one core 1.
are respectively positioned and engaged with the holes 1c to form a core set. The core group is cup-shaped case 3,
4 are sandwiched from the protruding sides of poles 1e and 2e, respectively. Step portions 3a, 4a are formed inside the opening peripheries of the cases 3, 4, and the peripheral end surfaces of the cores 1, 2 press-fitted into the cases 3, 4 and the step portions 1a, 2a of the cores 1, 2 form a step portion 3a. , 4a, and the depth of press-fitting of the cores 1 and 2 is regulated. Further, at the position where the stepped portions 1a, 2a are fitted into the notches 1b, 2b, the end surfaces of the cases 3, 4 are punched from the outside into a rhombus shape a with a V-shaped punch 10 as shown in FIGS. 2 and 4. The caulking process is performed so that the caulking parts 3b and 4b are bent inward.

When the V-shaped punch 10 is pressed and caulked as described above, the caulked portion 3b of the case 3 is locked to the stepped portion 2a of the core 2, as shown in FIGS. 5 and 6, and the caulked portion of the case 4 is 4b is locked to the stepped portion 1a of the core 1 as shown in FIGS. Stepped section 3
a, 4a, and the cases 3 and 4 are fixed via the core assembly.

At the center of each of the cores 1 and 2 and the cases 3 and 4, a comb-shaped pole 1 is provided, as shown in FIGS. 1 to 3.
e, 2e, 3c, 4c are formed and arranged so that the core and case poles are alternately combined,
A coil bobbin 6 on which an excitation coil 5 is wound is fitted onto the outer periphery of the coil bobbin 6, and the protrusions 1f and 2f on the peripheral edges of the cores 1 and 2 and the recesses 3d and 4 of the cases 3 and 4
d are engaged to determine the relative angular position of the core and case. Furthermore, the pole 1e of core 1
The positions of the poles 2e of the core 2 are shifted by half a pitch.

When the case step portions 3a, 4a are configured so that the peripheral end faces of the cores 1, 2 and each step portion 1a, 2a are press-fitted into the case step portions 3a, 4a, when positioning the center of each pole on the outer periphery of the core, the core Accuracy can be improved by eliminating play between 1 and 2, and the degree of adhesion can be increased to make it easier for magnetic flux to pass through.
When pressed by V-shaped punch 10, punch 10
The force is applied to the semicircular step portions 1a and 2a at the cutout portion 1.
Since it can be received by b and 2b, even a thin core material has sufficient strength. Also, to explain how the force is applied after caulking with reference to Figs. 6 and 7, the tensile forces b and b that pull the cases 3 and 4 are the same as the tensile force that the cores 1 and 2 each pull on the other core. Therefore, the pulling forces b, b become forces d, d that press the cores together. Therefore, the cores 1 and 2 and the cases 3 and 4 can be firmly connected together. When disassembling the case due to a defect after assembly, the cases 3 and 4 can be disassembled by raising the caulked portions 3d and 4d with an appropriate jig, thereby reducing production loss.

A mounting plate 7 and a side plate 8, to which bearings 11 and 11 are respectively fixed, are fixed to the cases 3 and 4 through holes 3e and 4e and dowels 7a and 8a. Bearing 1
A rotor shaft 12 to which a rotor 9 is fixed is supported by the rotor shafts 1 and 11, and the comb-shaped poles are arranged opposite to each other on the rotor 9.

When the small motor structure is configured as described above, the cases 3 and 4 are fixed through the core assembly without welding, which eliminates the adverse effects of high temperatures, and the cases 3 and 4 can be brought into contact with nickel plating, labels, etc. There is no need to cover parts, and since plasma welding is not performed, it is no longer necessary to bring argon gas into the assembly process, and large-scale equipment dedicated to welding can be omitted, reducing production costs and reducing worker costs. The feeling of anxiety disappears. When cases 3 and 4 are caulked, the tensile force acting on the cases becomes a force that presses the cores together, and the cores 1 and 2
The bonding force between cores 1 and 2 is strengthened, and cores 1 and 2 are not separated without using any other bonding structure.
Processing of the core and case is also simplified, making it possible to create a motor with excellent productivity.

FIGS. 8 and 9 show modified examples of the stepped portions 1a, 2a and notches 1b, 2b provided in the cores 1, 2,
The stepped portions 1a and 2a are formed in the notches 1b and 2d of the cores 1 and 2 at the same position so as to be located close to each other. The thickness of the stepped portions 1a and 2a may be made thinner than the other portions of the cores 1 and 2. In this embodiment as well, cases 3 and 4 are similar to FIG.
The tensile forces b and b become forces d and d that press the cores 1 and 2 together, and the cases 3 and 4 are also reliably connected.

Figures 10 to 12 show bent pieces 3g, 3h, 4g, 4h that can be bent at the cuts in cases 3 and 4.
are provided, the bent pieces 3g and 3h are attached to the stepped portion 2a of the core 2, and the bent pieces 4g and 4h are attached to the stepped portion 1a of the core 1.
This is another embodiment in which the cases 3 and 4 are fixed by bending and locking them respectively. With this configuration, the case and core are bonded with stronger bonding force.

Figures 13 and 14 show still another embodiment in which the cases 3 and 4 and the cores 1 and 2 are locked using pins 13.
By driving in, the cores 1 and 2 will not be separated and the cases 3 and 4 will be securely fixed.

[Effect of idea]

As described above, the present invention has the steps and notches formed on the peripheral edges of two annular cores fit together, and the steps formed on one core and the notch formed on the other core. By locking the outer side of the case and the stepped portion at the fitting position with the notch, the opposing core and case are locked to each other, one case is brought into contact with the other, and the case is closed. The tensile force applied to the stepped portions by The comrades are securely abutted and fixed, and the processing of the core and case is simplified, making it possible to create a motor with excellent productivity.There is no need to cover the contact part of the case with nickel plating or labels, etc. Since plasma welding is not performed, there is no need to bring argon gas into the assembly process, and large-scale equipment dedicated to welding can be omitted, reducing production costs and eliminating the sense of anxiety for workers. It is possible to provide a compact motor structure with excellent effects.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a cross-sectional front view of the small motor structure, FIG. 2 is a cross-sectional side view of the small motor structure, FIG. 3 is a cross-sectional side view of the core, and FIG. 4 is a small-sized motor structure. A perspective view of the exterior appearance of the motor, FIG. 5 is a plan view of the main parts showing the side surface of the case, the steps and notches of the core, and FIG. 6 is a cross-sectional side view of the main parts of the core and case taken along the - line in FIG. Figure 7 is a cross-sectional side view of the main parts of the core and case taken along the - line in Figure 5;
The figure is a perspective view of the main part of a modified example of the step part and notch part of the core, Fig. 9 is a sectional side view of the main part of the core and case of Fig. 8, and Fig. 10 is another embodiment of the locking part of the case. A plan view, FIG. 11 is a sectional side view of the main parts of the core and case in FIG. 10, FIG. 12 is a sectional front view of the main parts in FIG. 10, and FIG. 13 is a still another embodiment of the locking part of the case. Fig. 14 is a cross-sectional side view of essential parts of the core and case shown in Fig. 13, Fig. 15 is a cross-sectional side view of a conventional small motor, and Fig. 16 is an exploded cross-sectional side view of the same core and case. . 1, 2... Annular core, 1a, 2a... Step part, 1b, 2b... Notch part, 1e, 2e, 3
c, 4c... comb-shaped pole, 3, 4... cup-shaped case, 9... rotor.

Claims (1)

[Scope of utility model registration request] Steps and notches are formed on the peripheral edges of two annular cores each having a comb-shaped pole facing the rotor in the center, and the two cores are arranged so that the poles protrude in opposite directions. At the same time, the step part of one core and the notch part of the other core are respectively fitted to form a core assembly, and the core assembly is sandwiched between two cup-shaped cases, and the step part and the notch part are fitted together. A small motor structure in which the outer side of the case and the step part are engaged at the fitting part position.