JPS596148Y2 - step motor - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to the structure of a step motor.

In the conventional step motor, as shown in Fig. 1, a yoke opening to which a coil is attached is extended to form a support part 8, and a recess 2 formed in the support part 8 and a recess 2 formed in the end face of the iron core are formed. There was already a model in which both ends of the shaft to the rotor were pivotally supported in the recessed part.

However, in such conventional step motors, it is difficult to achieve dimensional accuracy of the pivot part of the rotor, and the position of the concave part 2 varies, which affects the rotational performance of the magnetic pole teeth formed on the yoke opening. There were manufacturing disadvantages in that it was difficult to achieve parallelism between the magnet part and the child, and during assembly, the assembly work was difficult due to the presence of eight supporting parts.

The present invention was developed in view of these conventional drawbacks.
The purpose is to facilitate manufacturing control by making it easier to achieve parallelism between the magnetic pole tooth portion formed at the yoke mouth and the magnet portion to the rotor.

Hereinafter, the present invention will be explained based on the drawings of the embodiments.

FIG. 2 is a sectional view of the step motor of the present invention, FIG. 3 is a perspective view showing the assembly, FIG. 4 is a perspective view of its external appearance, and FIG. 5 is a side view.

In the figure, 1 is a coil tube in which a coil wire 1a is wound around an iron core 2, and the iron core 2 passes through the center.
Both ends of the yoke 3 are caulked and fixed to both legs of a yoke 3 shaped like a U-shape.

One leg 3b of this yoke 3 has wide magnetic pole teeth 8a coaxially with the iron core 2 and protruding radially from the center, and narrow magnetic pole teeth 8 protruding from the outside toward the center so as to fit between the wide magnetic pole teeth 8a.
It is provided with a magnetic pole tooth portion 8 consisting of b.

The wide magnetic pole teeth 8a and the narrow magnetic pole teeth 8b are arranged in a well-known manner so that adjacent angles of their respective center lines have a magnitude relationship for rotation in a fixed direction.

The planar shape of one leg 3b is U-shaped, and several locking portions 3a are cut out at equal distances from the center of the magnetic pole tooth portion 8.

The end face of the iron core 2 fixed to one of the leg pieces 3b is formed with a substantially conical recess 2a for pivotally supporting the shaft of a rotor, which will be described later.

4 is a rotor in which a shaft 4b is passed through an annular magnet plate 4a which is alternately magnetized with N and S poles corresponding to the magnetic pole teeth 8; 5 is a support ring, which is a cylindrical portion surrounding the outer periphery of the rotor 4; A bridging piece 5b protrudes from one edge of 5a, and a locking portion 5C corresponding to the locking portion 3a projects from the other edge.

6 is a shaft hole formed in the center of the bridging piece 5b.

Next, the assembly of the step motor of the present invention will be explained.

One end of the shaft 4b of the rotor 4 is pivotally supported in the recess 2a of the iron core 2,
The other end of the shaft 4b is inserted into the shaft hole 6, and the locking piece 5C of the support ring 5 is locked with the locking portion 3a of the yoke 3.

Note that the shape of the tip of the recess 2a and the shaft 4b pivotally supported therein is as follows:
The other shaft 4b is selected as appropriate to reduce frictional resistance.
It is recommended to equip Watusha-7.

Thus, the annular magnet plate 4a of the rotor 4 faces the magnetic pole tooth portion 8 of the yoke 3 substantially in parallel with a predetermined space therebetween.

As described above, the step motor of the present invention has four parts formed on the end face of an iron core fixed to one of the legs, a locking part formed in a notch shape on the one leg, and the outer periphery of the rotor. a cylindrical part surrounding the cylindrical part, a bridging piece with a shaft hole formed and protruding from one end edge of the cylindrical part, and a locking piece protruding from the other end of the cylindrical part corresponding to the locking part. A support ring consisting of a yoke is fixed to one of the leg pieces so that the rotor is pivotally supported by the recess and the shaft hole, so that the magnetic pole teeth formed in the yoke and the magnet part of the rotor are connected to each other. It is easy to achieve parallelism between the rotor and the rotor, and therefore the gap can be kept constant, and the rotor can be mounted on the yoke extremely easily.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a conventional step motor, Fig. 2 is a sectional view of the step motor of the present invention, Fig. 3 is a perspective view showing assembly, Fig. 4 is a perspective view of its external appearance, and Fig. 5 is a side view. It is a diagram. 1... Coil tube, 2... Iron core, 2a.
...Recess, 3...Yoke, 3a...
...Locking part, 4...Rotor, 4a...
Annular magnet plate, 4b... shaft, 5... support ring, 5a... cylindrical portion, 5b... bridging piece, 6...
...Shaft hole, 7... Watscher 8...
...Magnetic pole teeth.

Claims (1)

[Scope of utility model registration request] An iron core wrapped in a coil is fixed to both opposing leg pieces that are U-shaped, and one leg has wide magnetic pole teeth that protrude radially from the center on the same axis as the iron core, and a wide magnetic pole tooth that fits between them. A yoke is provided with a magnetic pole tooth portion consisting of narrow magnetic pole teeth protruding from the outside toward the center, and an annular magnet plate is alternately magnetized with N poles and S poles corresponding to the magnetic pole tooth portions. In a step motor consisting of a rotor with a shaft passing through it, and an annular magnet plate of the rotor facing the magnetic pole teeth of the yoke across a space, the end face of the iron core fixed to one of the leg pieces. A concave portion is formed in the rotor, and a locking portion is notched in the one leg piece, and a cylindrical portion surrounding the outer periphery of the rotor and a shaft hole are formed from one end edge of the cylindrical portion. A support ring consisting of a protruding bridging piece and a locking piece protruding from the other end edge corresponding to the locking part is locked to the one leg piece, and the rotor is moved into the recessed part. and a step motor pivotally supported in the shaft hole.