JPS6198149A - Step motor - Google Patents

Abstract

PURPOSE:To improve the efficiency of a magnetic path by using a U-shaped stator piece having opposed ends and a gap forming ends in a pair of housings. CONSTITUTION:A bush 3 is provided, a disc-shaped magnet 4 is mounted on a rotor 1, stator securing slot group is radially formed on housings 5, 6, and U-shaped stator pieces 17a, 17b are secured. The housings 5, 6 are interposed between a mounting plate 14 and a retaining plate 15, and integrally associated by a bolt 16. The stators 17 are formed by contacting the opposed ends 23 of the stator pieces 17a, 17b, and forming a gap G for filling the peripheral edge of the magnet of the rotor 1 between gap forming ends 24. Coils 20, 20' are contained in coil containing slots for surrounding the ends 24 at the assembling time, the housings 5, 6 are superposed and opposed, epoxy resin is filled and integrally secured. Thus, since the ends 23 can be contacted irrespective of the warpages of the housings 5, 6, the loss of the magnetic path can be reduced.

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to a step motor.

[Background technology]

In a step motor, a large number of magnetic pole parts are formed in the circumferential direction of the peripheral edge of the rotor, and this peripheral edge is positioned in the gap between at least one pair of stators, and each stator is provided with a coil. It is arranged in two housings and is formed by butting the two housings together. However, there was a drawback that the stators could not be butted together due to warpage during housing molding or distortion due to casting of the coil, resin for fixing the stator, etc., and the magnetic circuit was cut, resulting in poor efficiency.

[Purpose of the invention]

An object of the present invention is to provide a step motor that can secure a magnetic path through a stator without being affected by the precision of the housing or the distortion caused by resin casting.

[Disclosure of the invention]

The present invention includes a pair of housings that can be combined by matching each other, and a v@U having a butting end and a gap forming end that are internally housed in each housing and come into contact with a mutually recessed joint state when the housings are matched. It is equipped with a letter-shaped stator piece.

For this reason, the magnetic paths of the two divided stator pieces are connected by meshing at different stages due to the phase-notched joint state of the abutting ends, thereby improving efficiency.

A two-phase step motor according to an embodiment of the present invention is shown in FIGS. 1 to 6. That is, 1 is a rotor, a bush 3 is provided on a shaft 2, a disc-shaped magnet 4 is attached to a bush 31C, and magnetic pole portions N and S are formed on both sides of the peripheral edge and are arranged at regular intervals alternately in the circumferential direction. It is magnetized to. 5.6 is a housing in which stator insertion groove groups 7.8 are formed radially in a substantially symmetrical manner as shown in FIG. An insertion groove 9.10 is formed through each magnetic FM 9 (for example, the distance from N to the adjacent N pole), and furthermore, the fixed grooves 7.8 are at an electrical angle relative to the magnetic pole of the rotor 1. For example, they are spaced apart by n (integer) x 2π±π force, 6.5K in the example, so that they are shifted by πA. Also, a pair of arcuate coil storage grooves 11, 1
1', bearings 12, 12' are provided in the center, and a recess 13 for pulling out the J-type is formed at the opening edge. 14 is a plate for mounting, and 15 is a presser plate, both of which are made of metal. Through slit 2 corresponding to stator insertion i9.10 respectively.
2 and is attached by bolts 16 to the plate 14 and the holding plate 15.
They are integrally assembled by sandwiching the housing 5.6 between them.

Each stator 17 has a substantially U-shaped stator piece 178, 17b.
A gap is formed by butting the butt ends 23 into contact with each other to form a gap.
Each stator piece 17m, 17b has a respective stator insertion groove 9. A plurality of thin plates 18 are stacked for each lO to prevent eddy current product. In this case, the thin plates 1B are of two types, long and short, as shown in FIG.
The bottom part 25 of is press-fitted into the through slit 22 and fixed. For assembly, the coils 20 and 20' are accommodated in the coil storage grooves 11 and 11', and the lead wires 21 and 21' are drawn out from the recess 13. Stack the housings 5.6 and each stator piece 1
7L and 17b are passed through the stator insertion groove 9.10, the convex portions and concave portions of the abutting end portions 23 are engaged with each other alternately, and abutted against each other in a half-jointed state, and are then filled with epoxy resin or the like and fixed together. In addition, stator pieces t7a and 17b
may be caulked or welded to each plate 14,15.

FIG. 5 shows the positional relationship of the stator 17 with respect to the magnetic pole parts N and S. As mentioned above, each of the nine stators 17 is divided by the insertion groove group 7.8 and the magnet 4 is separated by the insertion groove 9.8.
The magnetic pole parts N and S are arranged at an angle equal to the electrical angle 2π,
Furthermore, as described above, the insertion groove groups 7 and 8 are shifted by π/2. Further, as shown in Fig. 6, a bipolar rectangular bulk wave is applied to the coil 20 ((S) in the same figure) and the coil 20' ((bl) in the same figure with a phase difference of π force. 20 ((11) '' in FIG. 6), the magnetic pole N in FIG.
appears, and in the stator 17 on the side of the insertion groove group 8, 1/2π
Assuming that the 5th tooth magnetic pole N has appeared from the previous point, the stator 17 on the insertion groove group 7 side has a repulsive force, and the stator 17 on the insertion groove group 8 side has an attractive force in the direction of arrow P, so that the rotor moves in the direction of arrow P. Rotates the π image in the direction of . At the subsequent time point t0, only the stator 17 on the side of the insertion groove group 8 reverses its magnetic pole, resulting in a repulsive force, but since the attractive force of arrow P is acting on the stator 17 on the side of the insertion groove group 7, the stator 17 further rotates by π/2 6 At the subsequent time point t2, the magnetic poles of only the stator 17 on the inserted group 8 side are reversed, so there is a repulsive force opposite to that described above.

The attraction force acts to rotate the π image, and thereafter the same operation is performed for each π force phase.゛Because it can be configured in this way, this step motor has two housings 5.
．． Since the abutting ends 23 of the stator pieces 17b and 17m arranged in the housing 6 can come into contact with each other and compensate for the warpage of the housing, it is possible to reduce losses in the magnetic path. ' Note that the shape of the abutting end portions 23 of the stator pieces 17 & 17b of the present invention is not limited to the embodiment, and may be
.

Any item that makes side contact with the condition may be used.

〔Effect of the invention〕

According to the step motor of the present invention, the efficiency of the magnetic path passing through the stator can be improved regardless of the dimensional accuracy of the housing, without complicating assembly due to its simple structure.

[Brief explanation of the drawing]

Figure fa1 is an exploded perspective view of one embodiment of this invention, 2nd rl
: One side plan view in disassembled state, Figure 3 is a sectional view, Figure 4 is a sectional view.
The figure is a view of two sets of stators butted together, FIG. 5 is a developed view showing the device relationship between the stator and rotor, and FIG. 6 is a waveform diagram of pulses applied to the coils. 5.6... Housing, 7.8... Stator insertion groove group, 9.10... Stator insertion groove, 17... Stator, 171, 17b... Stator piece, 23... Butt end Part, 24...Gap forming end, G...Gear gear 2゛2,゛# Fig. 3 Fig. 1 Fig. 4

Claims (1)

[Claims] A pair of housings that are combined by mating, and a substantially U-shaped stator piece that is internally housed in each housing and has a butting end and a gap-forming end that comes into contact with the two-way joint state by mating the housings. Equipped with step motor.