JPH0446104Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a support structure for gears used in clock movements and the like.

[Prior art and its problems] Conventionally, in supporting gears, there are structures for supporting gears in a cantilevered manner, for example, as shown in Figs. 3 and 4. The structures shown in the figures are used in clock movements. This is an example.

In the figure, a gear 20 is commonly referred to as a Hinohirakusha, and this gear 20 has a large pinion part 20a and a small pinion part 20b on the same axis.
A rotating shaft 20c is protruded from the center position on the 0a side, and a sliding portion 20d is formed between the large pinion portion 20a and the small pinion portion 20b. And rotation axis 2
0c is pivotally supported by the base plate 21, the sliding part 20d is supported by the support member (hole stone) 23 of the back presser 22, and the small pinion part 20b is protruded to the outside of the support member 23 (upper side in the figure). There is. For this reason, the pinion part 20b and the gear 24 that meshes with the pinion part 20b.
is arranged at a higher position than the upper surface 22a of the back presser 22. Note that this gear 24 corresponds to an hour wheel in the illustrated case.

However, if the gear support structure has such a structure, the pinion part 20b and the gear 24 are arranged on the upper surface 22a of the back presser 22, so the pinion part 20b and the gear 24 are placed on the upper surface of the back presser 22. 2
There was a problem in that the thickness of the watch movement increased by the protruding thickness at 2a, making it impossible to make the watch thinner.

[Purpose of the invention] This invention was made in view of the above-mentioned circumstances, and its purpose is to provide a gear support structure that can contribute to making watches thinner.

[Main points of the invention] In order to achieve the above-mentioned object, this invention forms a notch-shaped opening in a part of the hole of the support member in which the first gear is rotatably supported, and the first gear is exposed through the opening. This is characterized in that the teeth of the first gear mesh with the second gear.

[Embodiment of the invention] This invention will be described in detail below based on an embodiment shown in the drawings.

FIG. 1 is a sectional view of the main parts when this invention is applied to a timepiece movement, and FIG. 2 is a plan view of the main parts.

In the figure, a timepiece movement 1 has a gear train 4 built in between a main plate 2 and a gear train bridge 3, and this gear train 4 transmits the rotation of a rotor 5 of a step motor sequentially from a rotor pinion portion 5a to the pointer side. It is becoming more and more like this.

The rotation of the rotor pinion portion 5a is transmitted to the fifth wheel & pinion 6 meshing therewith, and the rotation is transmitted to the fourth wheel & pinion 7, the third wheel & pinion 8, and the second wheel & pinion 9 while being sequentially decelerated.

The large pinion part 10a meshing with the pinion part 9a of the center wheel 9, the small pinion part 10b provided coaxially with the large pinion part 10a, and the central pinion part 10a protrude only at the central position on the side of the large pinion part 10a. a gear (hinoshiguruma) 10 consisting of a rotating shaft 10c, and a support member (hole stone) 12 provided in a hole 11a of the back presser 11 and facing the circumferential surface of the small pinion portion 10b. The portion consisting of the gear (hour wheel) 13 meshing with the pinion portion 10b is a component showing the gist of this invention.

Further, as shown in FIG. 2, the supporting member 12 has an opening 12a formed in the side surface thereof in the shape of a notch, which corresponds to the space where the gear (hour wheel) 13 meshes with the pinion portion 10b of the gear (hinoshi wheel) 10. A portion of the circumferential surface (tooth tip) of the small pinion portion 10b is exposed through this opening 12a. Further, the back presser 11 that holds the support member 12 is formed to have a thickness opposite to the thickness (height in the drawing) of the support member 12, and allows rotation of the gear (hour wheel) 13. A space 14 is formed. As a result, the upper surface positions of the pinion portion 10b, the support member 12, and the gear (hour wheel) 13 can be incorporated within the thickness of the back presser 11 without protruding outward beyond the upper surface 11b of the back presser 11. Moreover, its integration is easy.

Note that a second hand, a minute hand, and an hour hand (not shown) are attached to the gear shafts 7a, 9a, and 13a, respectively.

Further, in this embodiment, a support member which is a hole stone 12 is arranged in the hole 11a of the back presser 11, but the support member which is a hole stone 12 is removed and the back presser 11 is directly attached to the gear 10.
It may also be used as a supporting member.

[Effects of the invention] As explained in detail above, this invention forms a notch-shaped opening in a part of the hole of the support member in which the first gear is supported, and the first gear is exposed from the opening.
Since the second gear is meshed with the teeth of the second gear, the protrusion of the gear supported on the outer surface of the back plate, etc. can be reduced as much as possible. It can be made thinner.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main parts of this invention applied to a clock movement, Fig. 2 is a plan view of the main parts of Fig. 1, and Fig. 3 is a sectional view of the main parts of a conventional clock movement. FIG. 4 is a plan view of the main part of FIG. 3. 10...Gear (Hinoura wheel), 10b...Kana part, 11...Back presser, 12...Support member (anaishi),
12a...opening, 13...gear (hour wheel).

Claims (1)

[Claims for Utility Model Registration] A first gear having a shaft at one end and teeth at the other end; a bearing member rotatably supporting the shaft at the one end of the first gear; , a support member that rotatably supports the tooth at the other end of the first gear and has an opening narrower than the diameter of the tooth that exposes a part of the tooth; and the opening of the support member. The first part exposed from the
a second gear that meshes with the teeth of the gear within the thickness of the support member;