JPH0528543Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a connection structure between a time adjustment knob and a shaft of a clock, for example.

(Prior art) Conventionally, for example, in order to correct the indication of the hands of a watch, a correction knob was attached to a correction shaft by attaching the adjustment knob to the outer end of the correction shaft protruding from the back of the watch and to both arms of the correction knob. The correction knob and correction shaft are connected by drilling small holes of the same diameter, matching the small holes, and inserting a connecting pin.

(Problems to be Solved by the Invention) In the above-mentioned prior art, when the correction knob and correction shaft are molded with plastic, there is a problem that the mold is easily damaged if the diameter of the small hole is small. Also, during assembly, the correction shaft must be pushed up, the correction shaft and the small hole of the correction knob must be aligned, and then the pin must be inserted, making assembly work very difficult if the item is small.

An object of the present invention is to provide a connection structure between a knob and a shaft that does not require a connection pin and can be easily assembled.

(Means for Solving the Problems) The knob is provided with a forked arm portion, and an engaging protrusion located opposite to the inside of this arm portion is integrally formed. The correction shaft is provided on the base plate so as to be movable in the direction of the correction axis, and is provided with a spring force in the return direction. This shaft has parallel parts formed on both sides of the head with a width approximately equal to the distance between the inner surfaces of the knob.
In the neck portion that is continuous with the head, guide grooves are provided in the circumferential direction of this shaft at intervals that are approximately the same as the intervals between the distal ends of the engagement protrusions. An engaging groove portion that is rotatably fitted is integrally formed.

(Function) To attach the knob to the shaft, push up the shaft against the spring force, position the guide groove of this shaft on the outside of the main plate, and then insert the correction knob along the main plate in a direction perpendicular to the correction shaft. Then, the engaging protrusion of the knob is fitted into the guide groove of the shaft, and after the engaging protrusion is aligned with the engaging groove in the guide groove, the force pushing up the correction shaft is removed. Then, the correction shaft is returned by the spring force, and the engagement protrusion of the knob fits into the engagement groove of the shaft, completing the installation of the correction knob.

The correction shaft is always subjected to a spring force, so that the correction knob comes into elastic contact with the engagement groove portion of the correction shaft, and the correction knob does not come off the shaft.

(Example) An example of the present invention will be described below with reference to the drawings.

Figure 1 shows the state when the hands are being corrected, and shows the outside of the main plate 1 on the back side of the watch (above the drawing).
A correction knob 2 is vertically erected, and the correction shaft 3 is pulled outward by this correction knob.
A needle drive pinion 3a, which is formed integrally with a correction shaft 3 located inside the gauge body, meshes with a transmission gear 4 for pointer correction.

As shown in the third diagram, the correction knob 2 is entirely U
Both ends of a semicircular correction knob 2a are extended in the tangential direction to form forked arm portions 2b, 2b. Engaging protrusions 2c having a circular cross section are integrally formed on opposing surfaces of the inner sides 2b, 2b of both arm portions at predetermined positions.

To explain the correction shaft 3, as shown in the second and third figures, parallel portions 3c are formed on both sides of the head 3b with a width approximately equal to the distance between the inner sides of both arm portions 2b, 2b of the correction knob 2. A guide groove portion 3d having a width approximately equal to the diameter of the engaging protrusion 2c of the correction knob is formed around the entire circumference of the neck portion. Engagement groove 3e
The guide groove 3d communicates with the head 3b at two opposing locations of the guide groove 3d, and the upper end is formed into a semicircular shape with a width approximately equal to the diameter of the locking protrusion 2c of the correction knob.

The body portion 3f of the correction shaft 3 is made longer than the height of the correction bearing portion 1a provided on the base plate 1 by the stroke for vertical movement of the correction shaft 3. Torso 3f
A spring receiving portion 3g having a diameter larger than that of the body is provided at the lower end of the spring. Below the spring receiving portion 3g, the needle turning pinion 3a is formed integrally with the correction shaft 3. Correction axis 3 continuous to the needle turning pinion 3a
A bearing hole 6 formed in the middle plate 6 is located at the lower end of the
A leg portion 3h is formed in a for slidably supporting the shaft.

Next, the connection method of the present invention will be explained.

First, the correction shaft 3 is fitted into the bearing portions 1a and 6a of the base plate 1 and the middle plate 6, and a downward return force is applied by the spring 5. Next, an upward force (arrow in FIG. 1) is applied from below the correction shaft 3 to push out the guide groove 3d of the correction shaft to the outside of the watch (towards the top of the drawing). Therefore, when the engaging protrusion 2c of the correction knob is aligned with the parallel part 3c of the head 3b and the guide groove 3d, and the applied force is removed, the correction shaft 3 is returned downward by the spring 5. It stops with the engagement protrusion 2c fitted into the upper end of the engagement groove 3e, and the needle drive pinion 3a disengages from the gear 4. At this time, since the correction knob 2 is always receiving a downward force from the spring 5, the correction knob will not fall off from the correction shaft unless a special force is applied from below the correction shaft 3.

When adjusting the time, if the adjustment knob 2 is held vertically as shown in the first figure, the engaging protrusion 2c will move upward, and the hand drive pinion 3a will also move upward together with the adjustment shaft 3. Since it meshes with the gear 4, the time can be adjusted by rotating the correction knob by a predetermined amount. When the correction knob 2 is turned down, the correction shaft 2 returns to its original position by the spring 5.
The needle turning pinion 3a is also disengaged and returns to its original position.

When removing the correction knob 2 from the correction shaft 3, apply an upward force from below the correction shaft to move the correction shaft, bring the guide groove 3d out of the main plate 1, and take out the correction knob through this. Easy to remove.

(Effects of the invention) As described above, according to the invention, the number of parts can be reduced, and there is no need to drill small holes in the knob or shaft, so damage to the mold can be prevented. moreover,
It is extremely easy to assemble and disassemble, and it is possible to obtain a connection structure between the correction knob and the correction shaft that is inexpensive to manufacture.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the knob in a vertically erected state, FIG. 2 is a front view of the shaft, and FIG. 3 is a plan view showing the state in which the knob and shaft are connected. 1...Main plate, 2...Knob, 2b...Arm, 2
c...Engaging protrusion, 3...Shaft, 3b...Head, 3d
...Guide groove portion, 3e...Engagement groove portion, 5...Spring.

Claims (1)

[Scope of Claim for Utility Model Registration] The knob is integrally formed with a forked arm and an engaging protrusion located opposite to the inside of this arm, and is movable in the axial direction on the base plate. The shaft, which is provided with a spring force in the returning direction and to which the knob is attached, has a head having a width approximately equal to the distance between the inner surfaces of the arms, and a shaft that is continuous with the head. A guide groove portion provided in the circumferential direction of the shaft at substantially the same interval as the spacing between the tip surfaces of the engagement protrusions, and an engagement groove portion that communicates with the guide groove portion and into which the engagement protrusion rotatably fits. A connection structure between a knob and a shaft, which is characterized by being integrally formed.