JPS6198150A - Step motor - Google Patents

Abstract

PURPOSE:To improve the positional accuracy of a stator by providing U-shaped stator pieces secured at the bottom to side plates, and housings having stator inserting slots passing through the stator pieces and coil containing slots. CONSTITUTION:A disc-shaped magnet 4 is mounted through a bush 3 on the shaft 2 of a rotor 1, and U-shaped stator pieces 17a, 17b are secured to stator inserting slots 9, 10 formed radially of housings 5, 6, and a coil containing slot 11 is formed. The housings 5, 6, and a coil containing slot 11 is formed. The housings 5, 6 are interposed between side plates 14 and 15 and integrally associated by a bolt. The stator pieces 17a, 17b have opposed ends 18, gap forming ends 19 and a bottom 23, a coil 20' is contained in the coil containing slot 11, and leads 21 are led. The ends 19 are opposed, epoxy resin is filled in the housings 5, 6, and integrally secured. Further, the bottom 23 is secured to the side plates 14, 15. Thus, the position of the stator 17 is decided by passing slits 22 of the plates 14, 15, thereby enhancing the positioning accuracy.

Description

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

[Background technology]

A step motor has a large number of magnetic poles formed in the circumferential direction of the peripheral edge of the rotor, the peripheral edge is positioned in the gap between at least one pair of stators, and a coil is provided in each stator. It is necessary to improve the eccentricity of the magnet with respect to the shaft, the magnetization division, and the positional accuracy of the rotor and stator. However, since the stator was inserted into the stator fixing groove of the conventional fitting and the stator was fixed with resin, the stator and stator fixing groove were loose, resulting in poor positioning accuracy of the stator and poor step angle accuracy. There was a downside to it being bad.

[Purpose of the invention]

An object of the present invention is to provide a step motor that can improve the positional accuracy of the stator without complicating assembly.

[Disclosure of the invention]

The present invention includes a pair of side plates, a substantially U-shaped stator piece whose bottom portion is fixed to these side plates and has an abutting end portion and a gap-forming end portion at the upper end, and a stator insertion groove passing through the substantially U-shaped stator piece. and a housing having a coil storage groove and sandwiched between the side plates so that abutting ends of the stator pieces come into contact with each other. The stator is fixedly positioned on a side plate made of metal etc. that can be machined with high positional accuracy, so compared to conventional methods where the stator is positioned in the stator fixing groove of the molded product housing, the stator can be positioned with better positional accuracy. A decision can be made.

A two-phase step motor according to an embodiment of the present invention is shown in FIGS. 1 to 5. That is, 1 is a-ta, @2 is provided with a gouche 3, and a disc-shaped magnet 4f is placed on the pufsheet 3:
Attachment: Magnetic pole portions N and S are formed on both sides of the peripheral edge portion and are regularly magnetized alternately at regular intervals in the direction of the magnet. 5
．． 6 is a housing with a stator insertion groove group 7 as shown in Fig. 2.
．． 8 are formed radially axially symmetrically, and each insertion groove group 7, 8 has a center spacing of 2π in electrical angle (2π is the spacing from the magnetic pole of the rotor 1, for example, N to the N pole of its neighbor). Insertion grooves 9.10 are formed through the insertion grooves 7.8, and the insertion grooves 7.8 are arranged so that the insertion grooves 7.8 are deviated from each other by π force in electrical angle with respect to the magnetic poles of the rotor 1, for example, n (integer)×2π2π/2. In the example, 6.
They are separated by 5π. Also, a pair of arc-shaped coil storage grooves 11
, 11', and bearings 12, 12' in the center.
A recess 13t for pulling out the reed machine is formed at the edge of the opening. Reference numeral 14.15 has a magnetic efficiency improving function and is made of a metal side plate with radial through slits 22 formed corresponding to the stator insertion grooves 9 and 10, and a bearing guide tube 24 provided in the center. Side plate 1 by side plate 16
By sandwiching the housing 5.6 between the housings 4.15 and 4.15, they are assembled into one piece.

Each stator 17 has an abutting end 18 and a gap forming end 1
A gap G is created in which the substantially U-shaped stator pieces 171 #17k) having 9 are brought into contact so that the butted ends 18 are in contact with each other, and the peripheral edge of the magnet 4 of the rotor 1 is inserted between the gap forming ends 19.
Each stator piece 17 and 17b is a stator insertion groove in which multiple stators are stacked to prevent eddy current loss).
The cut portion 23 is inserted into the through slit 22 of the side plate 14.15 and erected, and then caulked. In addition, the carp A/20, 20/ is stored in the coil storage @11, 11', and the lead wire 21,
21' is pulled out from the recess 13.

Each stator piece is 17m long with the housing 5.6 stacked on top of each other.

171) Insert into the housing 5.6 with the side plate 14.15 fixed to the T-side plate 14.15.
6 between the bolts 16 and the stator pieces 17.a, 1.
7b are butted, and the I/Using 5.6 is filled with epoxy resin or the like and fixed together.

FIG. 4 shows the positional relationship of the stator 17 with respect to the magnetic pole parts N and S, and each of the stators 17 divided by the insertion groove groups 7.8 as described above is connected to the magnet 4 by the insertion groove 9.
The magnetic pole parts N and S are arranged at an angle equal to the electrical angle 2π,
Moreover, as described above, there is a deviation of π/2 between the insertion groups 7 and 8. In addition, as shown in Fig. 5, carp Az20 (same figure (a)
)) and the carp A/20' ((b) in the same figure), a bipolar rectangular wave bus is applied with a phase shift of π force. Therefore, the time t of carp 1v20 (FIG. 5(a)). With a half stroke M from
appears, and the magnetic pole N shown in FIG. 4 has appeared on the stator 17 on the insertion groove group 8 side from a point 1/2π before. Due to the suction force in the direction of arrow P on the stator 17, the rotor
Rotate by π4 in the direction of . At the subsequent time point t, only the stator 17 on the insertion groove group 8 side 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 insertion groove group 7 side, the stator 17 further rotates by π force. At the subsequent time point t2, the magnetic poles of only the stator 17 on the side of the insertion groove group 8 are reversed, so there is a repulsive force opposite to that described above.

The suction force acts to make π1 rotation 5, and thereafter the ψ phase step is performed in the same manner.

With this configuration, the position of the stator 17 in this step motor is determined by the through slit 22 of the side plate 14.15, and is not affected by the accuracy of the insertion groove of the housing 5.6, which is a molded product. becomes extremely high. In this regard, conventionally, for example, the stator 17 has a thickness of 0.
．． When stacking 4 T-3m silicon steel plates, the thickness tolerance is about ±0.03, so the thickness of 4 stacked T-plates is 1.
Therefore, it is necessary to set the fixing groove at 1.3 tm, but in this case, it is fine if the plate is thick, but if it is thin, a backlash of 0.2 tm or more will occur. do. Therefore, it is possible to easily set the step angle accuracy to a desired position without variation.

Furthermore, a bearing guide 2 is installed in the center of the side plate 14.15.
4, the bearings 12 and 12' will be connected to this guide 2.
4, the position of the rotor leg 2 with respect to the stator 17 can be obtained with high accuracy, and the roundness of the rotor 1 and the stator 17 can also be improved.

Note that the stator pieces 171 and 17b may be formed of a single plate instead of being laminated. Further, the bottom part 23 of the stator 17 may be press-fitted into the slit 22 or welded, and the bottom part 23 of the stator 17 may be fixed.
Fi is fine.

〔Effect of the invention〕

According to the step motor of the present invention, the positional accuracy of the stator, which was dependent on the accuracy of the conventional molded housing, can be obtained (by using the side plate, which is easy to achieve accuracy), and the stator position lIN
This has the effect of improving the degree of performance compared to the conventional method.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of a simple embodiment of the present invention, Fig. 2 is a plan view of one of the divided states, Fig. 3 is a sectional view, and Fig. 4 is an exploded explanatory view showing the positional relationship between the stator and rotor. FIG. 5 is a waveform diagram of pulses applied to the coil. 5.6...Housing, 7,8...Stator insertion groove group, 9,10...Stator insertion groove, 17...Stator, 17a, 17b・7-Stator piece, 18...
- Butt end, 19... Gap forming end, 22...
・Through slit, G...Gap IC/:, '%゛C:'' Fig. 1 Fig. 3

Claims (1)

[Claims] A pair of side plates, a substantially U-shaped stator piece whose bottom is fixed to these side plates and has an abutting end and a gap-forming end at its upper end, and a stator insertion groove and a coil storage groove passing through the substantially U-shaped stator piece. and a housing that is sandwiched between the side plates so that abutting ends of the stator pieces come into contact with each other.