JPS6181164A - Step motor - Google Patents

Abstract

PURPOSE:To improve the workability and to accurately secure a stator by forming the stator inserting groove of a housing with a bottom, and forming an elastic groove at the stator, thereby preventing resin from flowing out. CONSTITUTION:A step motor is composed of a rotor mounted with a disc-shaped magnet on a shaft, a stator 17' and a housing 5'. Radial stator securing grooves 9', 10' secured with stator pieces 17'a are formed with a bottom in the housing 5'. A lower end projection 23 formed with the lower end elastic groove 22 of the piece 17'a is elastically contacted with the bottom 24. Thus, since the end 25 of the piece 17'a is projected at B from the end 5'a of the housing 5', a pressing jig is used to press it to bring the both ends 25, 5'a in coincidence. Resin is filled and cured in this state. Thus, the resin is not flowed out from the housing 5', thereby effectively securing the coils 20, 20 and pieces 17'a.

Description

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

[Background technology]

A step motor in which a large number of magnetic pole parts are formed in the circumferential direction of the peripheral edge of a disc-shaped rotor, the peripheral edge is positioned in the gap between at least a pair of stators, and a coil is provided in each stator has a 'JJ ratio of 1 [ 1. In order to increase the 1st rate, it is necessary to keep the gap between the 1stator and the stator narrow and constant. For this reason, conventionally, the stator is inserted into the stator fixing groove of the housing, the end face of the stator is received by a jig, and the other end of the stator is pressed, and the stator is fixed to the housing using resin with the end face of the stator in close contact with the jig. Was.

However, the resin easily leaked out of the housing, posing a problem in terms of work.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The step motor, which is the basis of the present invention, will be specifically explained below with reference to FIGS. 3 to 11.

That is, 1 is a rotor, a bush 3 is provided on a shaft 2, a disk-shaped magnet 4 is attached to a bush 3, and a magnetic pole part N is attached.

S is formed on both sides of the peripheral portion and is regularly magnetized alternately at regular intervals in the circumferential direction. 5.6 is a housing, and as shown in FIG. iM9
．． LQ is formed through the fixing grooves 7.8, and the fixing grooves 7.8 are formed through U.
For example, they are spaced apart by n (integer)X2π±π/2, or 65π in the embodiment, so that they are shifted by π/2 in air angle from the magnetic pole of the rotor l. There is also a pair of arc-shaped coil storage dlls.

11', a bearing 12, 12' is provided at the center, and a recess 13 for drawing out a lead wire is formed at the edge of the opening. 1
4 is the mounting plate, 15 is the presser slope, and the port 16 is used to attach the mounting plate 1.
The housing 5.6 is sandwiched between the housing 5.4 and the holding plate 15, thereby assembling the housing 5.6 into one piece.

Each stator 17 is a substantially U-shaped stator piece 17a.

+7b butt against each other to form a gap G into which the peripheral edge of the magnet 4 of the rotor l enters, and each stator piece 17a.

17b is each stator fixing 7aS9. A plurality of thin plates 18 are stacked on top of each other for each lO to prevent eddy current loss.

FIG. 9 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 fixing grooves 7.8 as described above is connected to the magnet 4 by the fixing groove 9.
The CJ11 pole parts N and S are arranged at an angle equal to 2π, and as noted 1j:1, the fixed groove groups 7.8 are shifted by π/2. Also, as shown in Figure 1O, the coil 20
Bipolar rectangular wave pulses are applied to the coil 20' ((a) in the figure) and the coil 20' (mountain in the figure) with a phase shift of π/2. Therefore, during a half cycle from time to of the coil 20 (FIG. 10(a)), the magnet iN shown in FIG. 9 appears in the stator 17 of the seven fixed groove groups, and the stator 17 of the fixed groove group 8 II+
Assuming that the magnetic pole N shown in FIG. 9 has appeared from a time l/2π before, the stator 17 on the fixed groove group 7 side has a repulsive force, and the stator 17 of the fixed groove group 8 LSI has an attractive force in the direction of the arrow P. The rotor rotates π/2 in the direction of arrow P.

At the subsequent time point t1, the magnetic poles of only the stators 17 of the eight fixed groove groups are reversed, resulting in a repulsive force, but since the attractive force of arrow P is acting on the stator 17 of the fixed groove group 7, the force is further increased by π/2
Rotate. At the subsequent time point t2, the stator 1 of the eight fixed groove groups
7, the magnetic poles are reversed, so the repulsive force and attractive force opposite to the above move (moves and rotates by π/2, and thereafter steps are performed every π/2 phase with the same operation.

FIG. 11 shows the stators 17a, 17b and coils 20, 20' inserted into the housing 5, and the lead wires 21, 21'
This is a method for pulling out the stators 17a, 17b and the coils 20 and 20' to the housing l using resin (the same applies to the housing 6). 19 is a presser jig, 20 is a rubber sheet, 2
1 is a surface plate.

The lower end of the stator 17b slightly protrudes from the housing 5, and the rubber sheet 20 presses the stator 17b against the holding jig 19, so that the end surface of the stator 17b becomes the same as the end surface of the housing 5. Therefore, if Evokin resin is poured and cured in this state, the stator 17b, coil 20.
20' is fixed to the housing 5 (a hole is provided in the holding jig 19 for injecting In resin).

However, since there is a gap A as shown in FIG. 11, there is a drawback that the resin flows out from this area, making it difficult to perform the work. In addition, since it is necessary to inject the resin with the coils 20 and 20' inserted, there is also the drawback that it is difficult to fill the resin.

[Purpose of the invention]

An object of the present invention is to provide a step motor that can prevent resin from flowing out without changing the position of the stator and can improve workability.

[Disclosure of the invention]

The present invention includes a housing having a stator fixing groove of a raised bottom, an elasticity imparting groove inserted into the stator fixing groove and elastically contacting the bottom surface of the stator fixing groove at the insertion end, and an injected resin in the stator fixing groove. a fixed stator, a coil is wound around the stator, a pair of housings to which the stator is fixed are overlapped to form a gap between the pair of stators, and a magnetized peripheral edge of a disc-shaped magnet of the rotor is provided. The gap is located at the same level as the gap. With the stator insertion groove of the housing at the bottom,
Elastic grooves are formed on the stator, and the stator is fixed to the housing while firmly adhering to the jig.
There is no need to worry about the resin flowing out, improving work efficiency, ensuring positional accuracy, and ensuring secure fixation.

An embodiment of this invention is shown in FIGS. 1 and 2.

This step motor is an improved version of the conventional example shown in FIGS. 3 to 1O. That is, the difference from the conventional example is that the stator fixings 19' and 10' provided in the housing 5' have bottoms, and that the lower end of the stator 17'a is provided with elasticity 11422, and the lower end protrusion 23 is attached to the bottom surface 24. This is the point where they are in ballistic contact. In Fig. 1, the stator 17
The end face 25 of 'a is li from the end face 5'a of the housing 5'.
Only B stands out. From this state, when the housing end face 5'a is pressed with the holding jig 19 as shown in FIG.
The end face 25 of 'a and the end face 5'a of the housing 5' coincide. Therefore, in this state, resin is injected and hardened. Alternatively, the resin is first injected into the housing 5', and then the stator 17'a is filled.

The resin may be cured by inserting the coils 20 and 20' and pressing with the holding jig 19. Either way housing 5
There is no lL1 arrangement from which the tree fingers flow out from '.

The same applies to the housing 6' (not shown).

In this way, in this step motor, since the stator fixing grooves 9' and to' of the housing 5' are bottomed, there is no fear of resin flowing out and the workability is good. In addition, since the resin can be poured into the housing 5' first, the resin will be sufficiently wrapped around each stator +7'a and firmly fixed, and there will be no overflow of the resin. Since 17'a is reliably flush with the end face of housing 5', positioning accuracy is ensured, and since the resin is spread around elasticity imparting groove 22, it can be fixed more reliably.

〔Effect of the invention〕

As described above, according to the step motor of the present invention, the elastic grooves in the stator prevent resin from flowing out without damaging the position of the stator, improve workability, and securely fix the stator. The effect is that it can be done.

[Brief explanation of drawings]

Fig. 1 is a sectional view of an embodiment of the present invention in which the stator is inserted, Fig. 2 is a sectional view of the stator positioned with a holding jig, and Fig. 3 is an exploded perspective view of the step motor that is the basis of this invention. , Figure 4 is a plan view of one of the divided states, and Figure 5 is a plan view of one of the divided states.
The figure is a sectional view, Figure 6 is a plan view of one side of the housing, and Figure 7 is a plan view of one side of the housing.
The figure is a sectional view taken along the line ■-■, Figure 8 is an exploded perspective view of one housing, Figure 9 is an exploded explanatory diagram showing the positional relationship between the stator and rotor, and Figure 1O is a diagram of the pulse applied to the coil. The waveform diagram and FIG. 11 are cross-sectional views showing the stator housing fixing means. l... Rotor, 4... Disc magnet, 5', 6'...
・Housing, 9', 10'...Stator fixing groove, 1
7'a-...Stator, 20.20'-:Film, 2
2... Elasticity imparting groove, N, S... Magnetic pole part, G... Gap @ 2 Figure 5 Figure 7 b Figure 8

Claims (1)

[Claims] a housing having a stator fixing groove with a bottom; a stator that is inserted into the stator fixing groove and has an elastic groove formed at its insertion end to make elastic contact with the bottom surface of the stator fixing groove, and is fixed to the stator fixing groove with injected resin; a coil is wound around the stator, and a pair of housings to which the stator is fixed are overlapped to form a gap between the pair of stators, and a magnetized peripheral edge of a disc-shaped magnet of the rotor is placed in the gap. A step motor that is positioned.