JP2999403B2 - Shaft bearing structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a bearing portion of a rotary decoration mechanism which rotates by receiving a driving force of a rotary decoration from a movement of a timepiece.

[0002]

2. Description of the Related Art As shown in FIG. 4, a bearing shaft 4 for holding a rotary decoration 2 in a conventional rotary decoration mechanism of this type has one end 4a connected to a movement 6 of a timepiece.
The other end 4 b was rotatably supported by the receiving stone 8. The end 4b of the bearing shaft 4 has a pointed pivot shape, and is rotatably supported by the inner surface of a conical or hemispherical concave portion 8a provided in the receiving stone 8 as shown in FIG. It had been.

[0003]

In the above-mentioned conventional bearing shaft 4 receiving structure, the distance from the fulcrum of the bearing shaft 4 to the receiving stone 8 is inclined and abuts when the bearing shaft 4 abuts vertically. It is different from the case. For this reason, if the bearing shaft 4 is slightly inclined, the load on the fulcrum of the bearing shaft 4 increases, and there is a problem that troubles such as stoppage occur.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described problems of the prior art, and has as its object to provide a shaft receiving structure in which the load does not increase even if the bearing shaft is inclined.

[0005]

According to the present invention, there is provided a bearing structure for a shaft,
A rotary ornament comprising a rocking lever driven by a clock mechanism for driving a timepiece, a gear mechanism for converting the rocking motion of the rocking lever into a rotary motion, and a rotary ornament rotating by the rotation of the gear mechanism. A support shaft that holds the rotary ornament and has one end connected to the gear mechanism; and a curved surface having a radius of curvature equal to a distance from a fulcrum of the support shaft to the other end of the support shaft. And a stone that rotatably supports the other end of the bearing shaft.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a bearing structure for a shaft according to the present invention,
The surface of the receiving stone is constituted by a curved surface whose radius of curvature is the distance from the fulcrum of the bearing shaft to the other end of the bearing shaft. For this reason, even if the bearing shaft is inclined, the distance from the fulcrum to the surface of the receiving stone does not change, so that an excessive load is not applied to the fulcrum.

[0007]

First, the construction of a movement of a timepiece according to an embodiment of the present invention will be described with reference to FIG. As shown in FIG. 3, the movement 10 in the present embodiment is generally constituted by a timepiece mechanism 12, a swing lever 14, and a gear mechanism 16.

The timepiece mechanism 12 includes a drive motor (not shown), a rotor wheel 18 rotationally driven by the drive motor, and a wheel train 20 driven by the rotor wheel 18 to drive hands and the like. ing. The gear train 20 shown in FIG. 3 specifically shows only those necessary for driving the swing lever 14. That is, what is shown is a fifth wheel 22 meshing with the rotor wheel 18, a fourth wheel 24 meshing with the fifth wheel 22, and an eccentric cam 26 rotationally driven by the fourth wheel 24. Constitutes a lever drive train wheel.

The swing lever 14 is formed of a material which can be elastically deformed into a substantially elongated rod shape, and an intermediate portion of the swing lever 14 is
At 4a, it is pivotally supported so as to be swingable in the left-right direction. At one end of the swing lever 14, a substantially rectangular engaging hole 14b having the same width as the outer shape of the eccentric cam 26 is provided.
4b is loosely fitted to the pin 26a of the eccentric cam 26. Further, a comb tooth 14c is provided at the other end of the swing lever 14, and the comb tooth 14c meshes with a crown wheel of the gear mechanism 16 described later. Further, the swing lever 14 is provided with a driven lever portion 14d which is pulled out from an intermediate portion supported by the swing shaft 14a and is provided in parallel with the upper half portion of the body of the swing lever 14. A substantially rectangular engaging hole 14e is provided at the tip. A stopper 28 fixed to the movement 10 protrudes into the engagement hole 14e. In addition, this driven lever portion 14d is
It is provided to support the reversing motion and to obtain a slow reversal when the rotating decoration is reversed.

Further, the gear mechanism 16 is composed of a crown wheel 30 that meshes with the comb teeth 14c of the swing lever 14, and a pinion wheel 32 that transmits the rotation of the crown wheel 30 in a direction perpendicular to the crown wheel 30. The crown wheel 30 is provided on the outer periphery around the rotation axis, and has a tooth portion 30a that meshes with the comb teeth 14c of the swing lever 14, and an outer peripheral edge of the disk protruding in the axial direction. And a tooth portion 30b that meshes with the pinion wheel 32. Also, Kana car 3
No. 2 has a brim portion 32a on the lower end side, and an axially extending tooth portion 32b is engraved on the upper end side. Further, the pinion wheel 32 has a hole at the center of the tooth portion 32b, and is rotatably loosely fitted to an insertion shaft 34 fixed to the movement 10. For this reason, the pinion wheel 32 is freely movable in the vertical direction in the figure, and the downward movement is such that the collar portion 32a comes into contact with the lower frame portion 36 formed at the lower end of the movement 10. Is limited by

In the movement 10 having the above configuration, when the rotor wheel 18 is driven to rotate by the drive motor, the eccentric cam 26 is rotated via the fifth wheel 22 and the fourth wheel 24. The rotation of the eccentric cam 26 causes the pin 26a to rotate.
Moves eccentrically, and the swing lever 14 swings due to the eccentric movement. When the swing lever 14 swings in this manner, the comb teeth 14c swing right and left in the figure, and the crown wheel 30 rotates clockwise and counterclockwise by this movement. The rotation of the crown wheel 30 is transmitted to the pinion wheel 32, and is rotated to reciprocate left and right with respect to a vertical axis.

In the present embodiment, a support shaft 38 for holding a rotating decoration is attached to the lower end of the pinion wheel 32 of the movement 10 as described above. This bearing shaft 38 is a kana wheel 3
2 and is supported so as to be movable within a certain range in the axial direction. Accordingly, in the present embodiment, the fulcrum of the bearing shaft 38 is connected to the pinion wheel 32 and the insertion shaft 3.
4 is a position where it fits loosely.

FIG. 1 shows a bearing shaft 38 according to an embodiment of the present invention.
It is a fragmentary sectional view showing the receiving structure. As shown in FIG.
One end 38a of a support shaft 38 is attached to the pinion wheel 32 of the movement 10 described above. This bearing shaft 3
The other end 38b of 8 has a conical shape and has a pivot shape with a slightly rounded tip. Also,
A rotary ornament 40 is attached to the outer periphery of the bearing shaft 38.

Immediately below the bearing shaft 38, a receiving stone 42 fixed to a watch case is provided. A curved surface 42a is provided on the surface of the receiving stone 42.
The positional relationship is set so that the tip of the other end 38b of the bearing shaft 38 abuts vertically. This stone 4
The radius of curvature of the second curved surface 42a is set to a distance D from the fulcrum of the support shaft 38 to the tip of the other end 38b.

As described above, the gear mechanism 16 in the movement 10 in this embodiment has a structure in which the direction of the rotation shaft is changed to the vertical direction by the engagement of the crown wheel 30 and the pinion wheel 32. Thus, the crown wheel 30
When meshing with the pinion wheel 32, smooth rotation can be obtained by setting a relatively large play between the teeth, but the play causes a large play in the lateral direction in the figure. . Due to the occurrence of this play, Kana car 32
May slightly tilt, and the tilt causes the bearing shaft 38 to tilt greatly as shown in FIG. Thus, the bearing shaft 38
When the angle of inclination is large, the load of the conventional bearing structure increases due to the tip of the bearing shaft being pressed against the stone.
In this embodiment, since the curved surface 42a having a radius of curvature equal to the distance D from the fulcrum of the bearing shaft 38 to the tip of the end 38b is provided on the surface of the stone 42, the bearing shaft 38 is centered on the fulcrum. Since the distance from the fulcrum to the curved surface 42a of the receiving stone 42 is constant even if it is inclined, the tip of the end 38b of the bearing shaft 38 always abuts on the curved surface 42a vertically, without increasing the load. Rotate smoothly.

[0016]

According to the present invention, even if the bearing shaft for holding the rotary ornament is inclined, the tip of the bearing shaft always abuts against the stone, so that an excessive load is applied to the gear mechanism for driving the bearing shaft. , And the rotating decoration can be smoothly rotated at all times.

Even if the timepiece is placed on a slightly inclined surface or the like, it is possible to rotate the rotary decoration without applying any excessive load.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a bearing shaft receiving structure according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing a state where a bearing shaft shown in FIG. 1 is inclined.

FIG. 3 is a sectional view showing a configuration of a movement of the timepiece according to one embodiment of the present invention.

FIG. 4 is a partial cross-sectional view showing a conventional bearing shaft receiving structure.

FIG. 5 is a partial sectional view showing another receiving structure of a conventional bearing shaft.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Movement 12 Clock mechanism 14 Swing lever 16 Gear mechanism 30 Crown wheel 32 Pinion wheel 38 Bearing shaft 40 Rotating ornament 42 Reclining stone 42a Curved surface

Claims (1)

(57) [Claims] 1. A swinging lever driven by a clock mechanism for driving a timepiece, a gear mechanism for converting the swinging movement of the swinging lever into a rotational movement, and a rotating ornament rotating by the rotation of the gear mechanism. A rotating shaft that holds the rotating decoration and has one end connected to the gear mechanism; and a curved surface having a radius of curvature equal to a distance from a fulcrum of the bearing shaft to the other end of the bearing shaft. And a rock receiving stone rotatably supporting the other end of the bearing shaft on the curved surface.