JPH0348439Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a shaft support structure for gears that requires meshing without backlash.

(Prior Art) For example, it is preferable that there is no backlash in the engagement between the reference gear and the reference setting pinion of a watch.
In other words, if there is a bump, it will cause blurring and the indication of the reference alignment will be inaccurate.

(Problem that the invention attempts to solve) Therefore, care was taken to avoid any bumps between the guide gear and guide pinion, but when the two gears were assembled, the following problem occurred. . That is, if the gear is inserted with force, the teeth will join together, resulting in breakage, damage, or deformation of the teeth.

Therefore, a method of providing a taper on the upper surface of the tooth portion of the gear may be considered, but in this case, the mold for forming the gear becomes expensive and complicated.

(Means for solving the problems) This invention adopts the following technical means to solve the above problems.

In other words, the gear shaft support structure according to this invention is
A bearing that receives the lower end shaft of the insertion side gear is provided on the base plate so that it can be moved in the radial extension of the stationary side gear and can be elastically returned, and the upper edge of the bearing has a taper that descends toward the center of the stationary side gear. The lower end shaft is pressed against the upper end edge of the taper, the lower end shaft is inserted while separating the bearing from the fixed side gear, and the inserted gear is meshed with the fixed side gear by the elastic return force of the bearing. is its characteristic.

(Function) According to the above configuration, when the insertion side gear is lowered in a vertical direction, the lower end shaft of the insertion side gear comes into contact with the tapered upper end of the bearing and further presses the taper of the bearing, resulting in fixation. The bearing moves away from the fixed side gear on the radial extension of the side gear, and finally the lower end shaft of the insertion side gear is fitted into the bearing, where the restraining force (including pressing force) on the insertion side gear is released. Then, the above bearing returns to its original position due to elastic force,
The insertion side gear meshes with the stationary side gear.

(Example) This invention will be explained below based on illustrative drawings.

The drawings show one embodiment of this invention, with Fig. 1 being an enlarged longitudinal sectional view, Figs. 2 A to C being explanatory views of the process of supporting the insertion side gear, and Fig. 3 being a plan view of the bearing portion. .

In the figure, reference numeral 1 denotes a fixed side gear such as a reference gear, which is fixed on the main plate 3 in advance of the shaft end of an insertion side gear 2 such as a reference gear described below. 4 indicates the teeth of the fixed side gear. 5 indicates the teeth of the insertion side gear, and 6 indicates the lower end shaft thereof.

Reference numeral 7 denotes a bearing formed integrally with the base plate 3, and cutout grooves 8 are provided around three sides of the bearing 7 so that the bearing 7 can move in a radial extension of the stationary gear 1. The material for the base plate 3 is selected from a material that allows the bearing 7 to move and has an elastic return force, such as plastic.

Reference numeral 9 denotes a bearing hole formed in the bearing 7, and the formation position of the bearing hole 9 is determined when the insertion side gear 2 is inserted into the bearing hole 9 when the bearing 7 is in a normal state (no elastic force is acting). , the insertion side gear 2 is set at a position where it meshes properly with the stationary side gear 1.

Reference numeral 10 denotes a taper formed on the upper edge of the bearing 7, and the taper 10 is formed in such a shape that the edge on the side away from the stationary gear 1 descends toward the center of the stationary gear 1. .

The gear shaft support structure according to the above embodiment meshes the insertion side gear 2 with the stationary side gear 1 in the following manner.

That is, as shown in FIG. 2A, the insertion side gear 2 is lowered, the lower end shaft 6 is brought into contact with the upper part of the taper 10, and the lower end shaft 6 is further pushed down, so that the second
As shown in FIG. 2B, the bearing 7 is moved against the elastic force, and by continuing to press down, the lower end shaft 6 is fitted into the bearing hole 9 as shown in FIG. 2C. In addition,
When this state is viewed from above, it is the state shown by the imaginary line in FIG. 3. Next, when the force exerted on the lower end shaft 6 is released, specifically when the machine is being assembled, when the pressing machine is removed from the insertion side gear 2, the bearing 7 returns to its original position with elastic force. Then, the state is shown by the solid line in FIGS. 1 and 3. Thereafter, the insertion side gear 2 is positioned by a bearing provided in the upper case, and is prevented from shifting to the state shown by the imaginary line in FIG.

Although the above explanation exemplifies the reference gear and reference alignment of a watch, the object of the present invention is not limited to reference gears and reference alignment, but is widely applicable to meshing between gears that requires small backlash. can.

(Effects of the invention) As explained above, according to this invention, since the insertion side gear is not inserted from above, there is no damage or deformation of the teeth, and there is no need to provide a taper on the teeth. Since there is no such thing, the mold for the gear can be inexpensive and simple.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention, in which FIG. 1 is an enlarged sectional view, FIGS. 2A to 2C are explanatory views of the process of supporting the insertion side gear, and FIG. 3 is a plan view of the bearing portion. 1... Fixed side gear, 2... Insertion side gear, 3...
Main plate, 6... lower end shaft, 7... bearing, 10... taper.

Claims (1)

[Scope of utility model registration request] A bearing for receiving the lower end shaft of the insertion side gear is provided on the base plate so as to be movable on the radial extension of the stationary side gear and elastically returnable, and a taper is provided at the upper edge of the bearing that descends toward the center of the stationary side gear. The lower end shaft is pressed against the upper edge of the taper, the lower end shaft is pushed in while separating the bearing from the fixed side gear, and the inserted gear is meshed with the fixed side gear by the elastic return force of the bearing. A gear shaft support structure featuring: