JPH0626066Y2 - Stepping motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a stepping motor, and more particularly, to an improvement of a stepping motor that supports a rotary shaft by pressing one end surface of the rotary shaft with a pressing plate. .

(B) Conventional Technology Conventionally, about three types of configurations have been proposed as such a stepping motor.

As shown in FIGS. 3 and 4, the first configuration is such that a bottom portion 2 of a bottomed case 1 is cut and raised to form a plurality of comb teeth 3 in an annular shape, and an annular coil is provided around the outer circumference of the comb teeth 3. 4, the rotary shaft 6 having the magnetic rotor 5 mounted on the outer periphery is inserted inside the comb teeth 3, and the holding plate 8 having the holding piece 7 cut and raised by forming a U-shaped cut is provided. A ball 10 fixed to the bottom portion 2 of the bottom case 1 from the outside by spot welding or the like and put in a recess 9 formed in the end surface of the rotor shaft 6 thereof.
Then, the pressing piece 7 is pressed, and the other end of the rotary shaft 6 is rotatably supported by a bearing (not shown) arranged in the case.

That is, the thrust piece and the radial direction load of the rotary shaft 6 are supported by the restraining piece 7 of the restraining plate 8 fixed to the bottom portion 2 of the bottomed case 1 from the outside by spot welding or the like.

The second configuration, as shown in FIG. 5 and FIG.
A pair of locking holes 11 are formed on the side surface of the bottomed case 1 in the figure, and a pair of locking pieces 12 are erected from the edge of the restraining plate 8, and the tips of the locking pieces 12 are fixed to the locking holes 11. The holding plate 8 is fixed to the bottomed case 1 by fitting it in and locking it.

Further, in the third configuration, as shown in FIGS. 7 and 8, a holding plate 8 is placed on the bottom portion 2 of the bottomed case 1 shown in FIG. 3, and a holding plate dedicated cover 13 is placed thereon. Bottom case 1
It was supposed to be fixed to. In addition, reference numeral 14 indicates, for example, a cover 1 for exclusive use of the pressing plate in order to prevent the pressing plate 8 from rotating.
3 is a notch engaging with 3.

(C) Problems to be Solved by the Invention However, in the first configuration described above, if spot welding failure of the holding plate 8 occurs, there is a concern that the mechanical strength will be insufficient, and in the second configuration, locking will occur. There is a problem that extra steps such as formation of the holes 11 and the locking pieces 12 are required, resulting in high cost.

Further, in the third configuration, the presser plate exclusive cover 13 is required in addition to the presser plate 8, resulting in high cost and complicated assembly.

The present invention has been made to solve the above-mentioned conventional drawbacks, and an object of the present invention is to provide an inexpensive stepping motor in which a pressing plate that supports a rotating shaft can be securely fixed by simple assembly.

(D) Means for Solving the Problem In order to achieve such an object, the present invention is to cut and raise the bottom of a bottomed case to arrange a plurality of comb teeth in an annular shape, and to form an annular shape on the outer periphery of the comb teeth. Fit the coil wound on
A rotating plate with a magnetic rotor attached to the outer periphery is rotatably arranged inside the comb teeth so that this one end surface faces the bottom part, and a holding plate having a holding piece that presses one end surface of this rotating shaft. Therefore, a holding plate having the comb teeth inserted therein is inserted into an insertion hole formed at a position aligned with the comb teeth, and the holding plate is sandwiched between the bottom portion and the coil, and the holding plate receives the rotary shaft.

(E) Action The present invention equipped with such a means is such that if the annular coil is fitted on the outer periphery of the comb tooth after the comb tooth is inserted into the insertion hole formed in the retainer plate, the retainer plate is provided between the bottomed case and the coil. It is held by and is fixed so that rotation can be suppressed by comb teeth.

(F) Embodiment An embodiment of the present invention will be described below with reference to the drawings. In addition,
The same parts as those in the conventional example are designated by the same reference numerals.

1 and 2 are a longitudinal sectional view and an exploded perspective view showing an embodiment of the stepping motor of the present invention.

The bottom part 2 of the cylindrical bottomed case 1 is cut and raised at a plurality of places, and a plurality of comb teeth 3 are arranged in an annular shape at predetermined intervals.

A disk-shaped restraining plate 8 is fitted on the outer circumference of the annular comb tooth 3. The holding plate 8 has a U-shaped notch formed in the central portion and a holding piece 7 is cut and raised, and an insertion hole 15 is formed at a position where the holding piece 7 is aligned with the comb tooth 3 so as to be punched. It is formed by processing. The restraining plate 8 is arranged on the inner bottom portion 2 of the bottomed case 1 with the comb teeth 3 inserted through the insertion holes 15.

A coil 4 having a wire wound around a cylindrical bobbin 16 is fitted around the outer circumference of the annular comb tooth 3.

The coil 4 is fitted with a ring-shaped flange 17 and a comb tooth 18 on one side of an auxiliary yoke 19 having a comb tooth 18 formed by bending the inside of the flange 17 in both axial directions of a rotary shaft 6 described later. There is. The comb teeth 18 of the auxiliary yoke 19 are located in the gaps between the comb teeth 3.

A coil 20 similar to the coil 4 is fitted in the comb tooth 18 on the other side of the auxiliary yoke 19. Reference numeral 21 is a bobbin.

A cup-shaped outer case 22 is provided on the open end surface side of the bottomed case 1.
Is covered. A bearing 23 is attached to the central portion of the upper surface of the outer case 22. Comb teeth 24 formed by cutting in a U-shape around the bearing 23 are cut and raised inward to form a gap between the comb teeth 18. Has been inserted into.

A magnetic rotor 5 is attached to the outer circumference of the rotary shaft 6 and inserted into the hollow portions of the coils 4 and 20 to form a rotor. A recess 9 is formed on one end surface of the rotary shaft 6, and a ball 10 is arranged in the recess 9 and is inserted between the comb teeth 3 to bring the ball 10 into contact with a pressing piece 7 of a pressing plate 8,
It is rotatably held by being supported by a bearing 23.

In such a stepping motor, one end of the rotary shaft 6 is elastically supported by the restraining piece 7 of the restraining plate 8 via the ball 10 while being supported by the thrusting and radial directions, and the other end is supported by the bearing 23. Since it is pivotally supported by changing the polarity of the drive current to the coils 4 and 20, the rotary shaft 6 rotates in predetermined steps according to the change of the drive current.

At this time, the pressing plate 8 receives a rotational force as the rotating shaft 6 rotates, but the comb teeth 3 are inserted into the insertion holes 15 to prevent the pressing plate 8 from rotating.

The present invention is not limited to the configuration using the coils 4 and 20 and the auxiliary yoke 19 as described above.

(G) Effect of the Invention As described above, according to the present invention, the comb tooth 3 is inserted into the insertion hole 15 of the restraining plate 8 and the coil 4 is fitted on the outer periphery of the annular comb tooth 3. 8 is sandwiched between the bottomed case 1 and the coil 4, and the comb teeth 3
The rotation is suppressed at.

Therefore, for the comb tooth 3, the pressing plate 8 is connected to the coil 4
It is possible to fix the pressing plate 8 that supports the rotating shaft 6 and prevent the rotation by a simple assembly such as fitting, workability is good, and the cost can be easily reduced.

[Brief description of drawings]

1 and 2 are a longitudinal sectional view and an exploded perspective view showing an embodiment of the stepping motor of the present invention, and FIGS.
The figure shows a conventional stepping motor.
FIGS. 5, 5 and 7 are longitudinal sectional views, and FIGS. 4, 6 and 8 are exploded perspective views of main parts. 1 ... bottomed case, 2 ... bottom part, 3, 18, 24 ... comb teeth,
4, 20 ... Coil, 5 ... Magnetic rotor, 6 ... Rotation axis, 7 ...
Presser piece, 8 ... Presser plate, 9 ... Dimple, 10 ... Ball, 11 ...
Locking hole, 12 ... Locking piece, 13 ... Presser plate cover, 15
... Insertion hole, 16, 21 ... Bobbin, 19 ... Auxiliary yoke, 2
2 ... Outer case, 23 ... Bearing.

Claims (1)

[Scope of utility model registration request] 1. A bottomed case in which a plurality of comb teeth cut and raised from the bottom are arranged in an annular shape, a coil fitted on the outer periphery of the comb teeth, and a magnetic rotor is attached to the outer periphery so that one end surface faces the bottom. A stepping plate having a rotary shaft rotatably supported inside the comb tooth in this manner, and a presser plate having a presser piece for pressing the one end surface of the rotary shaft, and a presser plate arranged at the bottom portion. In the motor, the stepping motor is characterized in that the pressing plate is inserted between the comb tooth and an insertion hole formed at a position aligned with the comb tooth, and is housed between the bottom portion and the coil.