JPS6152619B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the bearing structure of a rotor for a small step motor used in a converter for an electronic timepiece.

In recent years, electronic watches, especially quartz watches, have been required to be thinner and have a longer lifespan. In order to achieve this requirement, it is necessary to reduce the loss of the rotor as much as possible and use the output of the motor effectively, so that the converter can be driven with low power consumption, and it is necessary to have a structure that can realize a thin design.

The structure of the bearing part of a conventional rotor is shown in Fig. 1, in which the left and right stators 2 and 3 are fixed together by a splicing plate 1 (the fixing part is not shown).
A rotor pinion 9 to which a rotor magnet 8 is fastened is pivotally supported by a flat hole stone 5 planted in the base plate 4 and a flat hole stone 7 planted in the gear train bridge 6.

Therefore, the left and right stators 2 and 3, which are integrated by the splicing plate 1, are disposed cross-sectionally between the main plate 4 having the flat-hole stones 5 and 7 and the gear train bridge 6 with an appropriate gap between them. Therefore, there are drawbacks such as the fact that it is impossible to reduce the thickness of the rotor portion below the total thickness of each component plus an appropriate gap.

In this case, the ideal cross-sectional positional relationship between the rotor magnet 8 fastened to the rotor pinion 9 and the left and right stators 2 and 3 is such that the rotor magnet 8 is axially magnetic with respect to the left and right stators 2 and 3. It is desirable that the rotor pinion 9 be fixed to the rotor pinion 9 at a position where it is not subjected to a strong attractive force, that is, at a position where the centers of the rotor magnet 8 and the left and right stators 2 and 3 in the thickness direction coincide. However, in reality, due to variations in the processing of the parts and the need to set agaki for the rotation of the rotor pinion 9, the centers of the rotor magnet 8 and the left and right stators 2 and 3 in the thickness direction do not always coincide, so that the shaft Since a magnetic attraction force is generated in the direction, the shoulder 9a or 9b of the rotor pinion 9 is attached to the end face 5 of the flat stone 5 or 7.
It comes into contact with a or 7a under force. Therefore, when the stator 3 is excited and the rotor pinion 9 rotates, the outer circumference of the rotor pinion 9 and the flat hole stone 5
Although resistance also occurs between the shoulder 9a or 9b of the rotor pinion 9 and the flat hole stone 5 or 7,
Since a large resistance is generated between the rotor pinion and the end face 5a or 7a of the rotor pinion, there is a drawback that a large output loss is caused especially in a rotor pinion with a small output.

The present invention has been made in order to eliminate the above-mentioned drawbacks, and the first purpose is to reduce the thickness of the rotor and thus the clock by intersecting the bearing part of the rotor with the splice plate in cross-section. The purpose of this is to forcibly generate the axial magnetic attraction force generated in the rotor pinion on the main plate side, and change the bearing method on the main plate side from the shoulder of the rotor pinion to the end face, thereby reducing the loss during rotor rotation. The objective is to reduce rotor power loss and prevent rotor output loss.

Embodiments of the present invention will be described below based on the drawings. In FIG.
and are welded and integrated by means such as spot welding. The base plate 4 to which the left and right stators 2 and 3 are fixed, which are integrated by the splicing plate 1, has at least a part of the part where the flat-hole stones 5 for bearings of the rotor pinion 9 having the rotor magnets 8 are planted. It penetrates into the thickness of the splice plate 1 to form a convex portion 4a.

Therefore, the thickness of the base plate 4 that overlaps with the sprinkling plate 1 other than the bearing part of the rotor pinion 9 does not require the need to push in the flat hole stone 5 or to prevent the tip of the rotor pinion 9 from protruding from the bottom surface of the base plate 4. Therefore, it becomes possible to make it extremely thin, and the thickness of the rotor part determined by the gear train bridge 6 having the flat bearing stone 7 on the upper surface side of the rotor pinion 9 and the lower surface of the main plate 4 can be significantly reduced. Become.

In FIG. 3, as in FIG. 1, the stators 2 and 3 integrated by the splice plate 1 are fixed to the base plate 4, and the base plate 4 is formed by penetrating into the thickness of the splice plate 1.
A bearing block 10 of a rotor pinion 9 is pushed into and fixed to the convex portion 4a. Now stator 2,3
Since the cross-sectional center position of the rotor magnet 8 is located closer to the ground plate 4 than the cross-sectional center position of the rotor magnet 8, the rotor pinion 9 having the rotor magnet 8 has an axial magnetic field in the direction shown by the arrow A. Attraction is working. On the other hand, the bearing block 10 fixed to the base plate 4 has a structure in which a hole stone 12 is pushed into a frame body 11, and a support stone 13 is fixed by fixing a spring 14 to the frame body 11.

Therefore, since the rotation direction of the side surface of the rotor pinion 9 is supported by the hole stone 12, and the end face of the handle 9c is supported by the support stone 13 in the bearing block 10, the shoulder of the rotor pinion 9 is supported as in the conventional case. Compared to the case where 9a contacts the end 5a of the flat stone 5, the frictional resistance during rotor rotation is significantly reduced.
Output loss can also be kept small. Also, the convex portion 4 of the base plate 4
Since a cross-sectionally overlaps the splint 1, even if a thicker bearing block 10 is used, the thickness of the rotor portion will not increase.

In the case of Fig. 4, the magnetic attraction force is acting in the direction of arrow A as in Fig. 3, and the protrusion 4a of the base plate 4 also overlaps the splint 1 in cross section; Only the hole stone 5 is pushed in, and a concave portion 4b is further machined from the lower surface side, and a stone catch seat 15 is pushed and fixed into the concave portion 4b so that the stone catch 15 is positioned below the hole stone 5. 16 is fixed to the base plate 4 with screws 17. Therefore, as in the case of FIG. 3, the end face of the rotor pinion 9 at the end 9c comes into contact with the jewel 15, so that the friction loss during rotor rotation is reduced, and the output loss is also kept small. Furthermore, the thickness of the rotor portion can be further reduced by the spring 14 compared to the bearing block 10.

In Fig. 5, a flat hole stone 5 for the bearing of the rotor pinion 9 is planted in the thick wall of the plate 1 that integrates the left and right stators 2 and 3, and the plate 1 is attached to the main plate. 4 in cross section, the thickness of the rotor portion can be made extremely thin.

In FIG. 6, similar to FIG. 3, a magnetic attraction force is acting in the direction of arrow A, so a part of the bearing portion of the rotor pinion 9 is pushed into the bearing block 10 which is fixed by being pushed into the thickness of the splice plate 1. Since the splint plate 1 overlaps the main plate 4 in cross section, the thickness of the rotor part does not increase even if a thicker bearing block 10 is used.
Furthermore, friction loss during rotor rotation is also reduced.

As described above, according to the present invention, the bearing portion of the rotor pinion is formed in the convex portion provided on the base plate, and the splint and the convex portion are overlapped in cross section, or the splint and the base plate having the bearing portion of the rotor pinion are overlapped in cross section. By overlapping the rotor in cross section, the thickness of the rotor can be made much thinner than before, making it possible to make the watch thinner.

In addition, by making the axial magnetic attractive force acting between the rotor magnet and the stator act on one side, that is, on the main plate side in the explanation, and receiving only the main plate side of the rotor pinion at the handle end surface, the rotor portion Since the output loss during rotor rotation can be reduced without increasing the thickness of the converter, the converter can be driven with lower power consumption, which has the effect of extending the life of the watch.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a rotor portion of a converter showing a conventional example, and FIGS. 2 to 6 are cross-sectional views of a rotor portion of a converter showing embodiments of the present invention. 1... splice plate, 2, 3... stator, 4... main plate, 5, 7... flat hole stone, 6... gear train bridge, 8... rotor magnet, 9... rotor pinion, 10... bearing Block.

Claims (1)

[Scope of Claims] 1. A stator in which left and right stator bodies separated into one body are integrated using means such as welding with spliced plates;
A converter having a rotor having a rotor magnet fastened to a rotor pinion, wherein at least a part of one bearing portion of the rotor is disposed so as to penetrate into the thickness of the splint plate. Bearing structure of converter rotor. 2. A bearing structure for a rotor for a converter, wherein the bearing portion of the rotor according to claim 1 is provided on a splint. 3. A stator in which the stator bodies separated into left and right sides are integrated using means such as welding with spliced plates;
In a converter having a rotor with a rotor magnet fastened to a rotor pinion, the rotation direction of the rotor is supported by a hole stone, and the axial direction is supported by a block stone, so that the bottom of the rotor is supported at the end surface. A bearing structure for a rotor for a converter, characterized in that at least a part of one of the bearing parts having a shaft-supporting structure is arranged so as to penetrate into the thickness of the splicing plate.