JPS60247187A - Fixing structure of case and glass of wristwatch - Google Patents

Abstract

PURPOSE:To improve the viewing state of a packing and to form the fixing part of a case and glass in a thin and compact state while eliminating the load applied to the processing of the case, by mounting a specific soft metal or non- metal packing. CONSTITUTION:An inner periphery 22 is formed to a case 20 by an upside step part 21 and glass has a strip like projection 31 with a width of 0.3mm. or less formed to the entire outer periphery thereof. A packing 40 is made of a soft metal with HV of 150 or less such as aluminum or copper or a non-metal material with heat resistance of 200-250 deg.C such as Teflon and has an I-shaped cross- sectional shape with a wall thickness of 0.3-0.1mm. and a height of 0.4-1.5mm.. At first, the packing 40 is mounted to the case 20 so as to be contacted with the inner periphery 22 of the upside step part 21 of said case 20. Next, the case 20 is placed on a hot plate to be heated to 200-250 deg.C. Hereupon, when the glass 30 is inserted into the packing 40 so as to be contacted with the inner periphery 42 thereof and the case 20 is removed from the hot plate, the case 20 is cooled to ambient temp. and the strip like projection of the glass 30 is sunk into the packing 40 to hold the watertightness and fixing force of the case 20 and the glass 30.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention provides a structure for fixing a watch case and a glass.

[Background of the invention]

The structure for attaching the case to the glass in a watertight manner has been a constant competition among manufacturers to find a structure that is thin, compact, and can be attached in such a way that the packaging is difficult to see.

[Prior art and problems]

The latest conventional technology that is the culmination of such ideas is the conventional example shown in FIGS. 1 and 2.

In Figure 1, a gasket 4 having a suction slope 6 is attached to the inner periphery 2 of the upper step of the case 1, and the glass 6 is attached to the inner circumference of the gasket 4 using the suction slope 6 and the lower slope 5 of the glass. It is characterized by being press-fitted to maintain fixing force and watertightness between the case 1 and the glass 6.

However, according to the same structure, the amount of compression of each glass 67 (due to wear of the inner periphery of the gasket 4 when press-fitting into the inner periphery of the gasket 4 and variations in radial tolerance of each part) is 1.
008 or more, and therefore the seal thickness also needs to be 350μ or more. - This causes a problem in that the seal 4 is too visible in appearance.Also, when press-fitting the glass 6, the seal 4 is dragged toward the bottom surface of the glass 6. The safety level of watertightness may be jeopardized due to the possibility of bending or buckling, so the height of the seal 4 needs to be about 1 degree.

Furthermore, it was difficult to insert the draw-in slope 6 into the packing 4 in terms of machining.

Fig. 2 shows an improved view of the seal 4 in Fig. 1, and is characterized in that a seal groove 8 is formed on the inner periphery of the upper step of the case 7, and the upper surface of the seal 9 is covered with the flange 10 of the case. Although the appearance of the packing and the dragging and buckling of the packing when press-fitting the glass are improved, the wear of the inner circumference of the packing and the necessity of the lead-in slope of the above embodiments are not improved.

In addition, in the case of the conventional example shown in Fig. 1, the inner periphery 2 of the upper step can be formed by press working and the profile accuracy is good, but in the case of Fig. 2 9, the packing groove has to be machined by cutting, and the profile accuracy is poor. It's hard to get out.

In addition, the profile shape of the packing groove 8 is often designed other than a rectangular shape with rounded corners, etc., and the profile shape is restricted due to the limitations of cutting technology, making it impossible to respond adequately to diversifying designs.

[Purpose of the invention]

The present invention solves the above-mentioned drawbacks by improving the appearance of the packing, making the fixing part of the case and glass thin and compact, and reducing the burden on the processing of the case← That is 1%4.

[Structure of the invention]

The structure of the present invention is to attach a thin-walled ■-shaped cross-section packing with a thickness of 0.3 mm or less and made of a soft metal with an HV of 150 or less or a non-metal that can withstand high temperatures of 200°C to the inner periphery of the upper step of the case. It is characterized by keeping the temperature at about 200 degrees Celsius, attaching glass having band-like protrusions of 0.3 mm or less on the outer periphery to the inner periphery of the packing, and then returning to room temperature and burning and fixing the glass to the case. be.

[Embodiments of the invention]

Embodiments of the present invention will be described below based on the drawings.

FIG. 3 is a sectional view showing the first embodiment of the present invention.
Figure 3(a) shows the completed product, and Figure 3(b) shows the case, glass, and packing removed.

The case 20 has an inner periphery 22 formed by an upper step portion 21 . The glass 60 has a width of 0.0 mm on the outer periphery. ．． Band-like protrusions 61 with a diameter of 3 mrn or less are formed around the entire circumference.

The packing 40 is made of a non-metal material such as aluminum, a soft metal with a copper ring HV150 or less, or a heat-resistant 20.0 to 250'C such as Teflon, and has a thickness of 0.3 mm to 0.1 mm, a height of 0,
It has a thin wall of 4 mm to 1.5 mm and an I-shaped cross section.

Next, the assembly procedure will be explained.

The gasket 40 is attached to the inner periphery 22 of the upper step 21 of the case 20 .

Next, place the case 20 on a hot plate and
When heated to 0°C, if the case material is stainless steel, the inner periphery 22 of the case 2o, that is, the inner periphery 42 of the packing 41, expands by 0.1 mm in diameter, and this also applies to the packing whose coefficient of thermal expansion is larger than that of stainless steel. Let's go. After that, the glass 60 is inserted into the inner periphery 42 of the gasket 40, and the case 20 is removed from the hot plate (and the case returns to its original position, and the band-shaped protrusion 61 of the glass 60 sinks into the gasket 4o, and the case 20 and the glass 6o are removed. Maintains watertightness and fixing power.

In our experiments, we used glass, 30, and case 20. Patsukin 4
Considering the tolerance of 0.0 mm, workability, watertightness, and fixing force, it is recommended to set the outer diameter of the band-like protrusion 61 of the glass 30 to 0.08 to 0.1 mm relative to the inner diameter of the gasket 4o. The best.

Further, the width of the outer circumferential protrusion of the glass 60 is 0.3 mm, and if it exceeds the width, it will not sink into the gasket 40 and the watertightness will not be sufficient, so the optimum width is around 0.2 mm.

FIG. 4 is a cross-sectional view of the second embodiment, which is completely the same as the first embodiment except that the shape of the band-like protrusion 32 on the outer periphery of the glass is changed.

〔Effect of the invention〕

As is clear from the above embodiments, according to the present invention, (1)
The height of the inner periphery of the case 22 is as thin as 0.4 mm (possibly possible, and the thickness of the packing 4o can be made 02 to 0.3 mm, so the packing is difficult to see externally, making it thin and compact in appearance. It looks neat.

(2) Since the packing groove 8 shown in FIG. 2 is not required on the inner periphery of the case 22, and the intake slope 6 shown in FIG. 1 is not required, the processing load is reduced.

Effects such as this will occur.

[Brief explanation of the drawing]

1 and 2 are partial sectional views of a case showing a conventional example, and FIGS. 3 and 4 are a partial sectional view of a case showing a first embodiment and a second embodiment of the present invention, respectively.
FIG. 3(b) is a partial sectional view of the case showing the embodiment.
The case, gasket, and glass shown in Figure (a) are shown in a disassembled state. 60...Glass, 61.62...Strip-shaped projection, 40...Putskin, 42...Inner periphery, 20...Case, 21 ......Upper step, 22...Inner circumference. Patent applicant Citizen Watch Co., Ltd. No. 3-0 (a) (b) 4 Figure 2

Claims (1)

[Claims] A packing is provided on the inner periphery of the upper step of the case.
°゛ In the structure that obtains airtightness and fixing force between the glass and the case by press-fitting, the glass has a band-like protrusion on the outer periphery with a width of 0.3 mm or less, and the seal is made of aluminum, a soft alloy of copper tube HV150 or less. , or made of a non-metallic material such as Teflon that can withstand high temperatures of 200 to 250°C, and has a radial thickness of O,'
A case having a ■-shaped cross section of 3 mm or less and equipped with the above-mentioned packing is kept warm at 200 to 250°C, the above-mentioned glass is attached, and then the temperature is returned to normal temperature, and the glass is attached to the case by the burnout effect. The case and glass are fixed to each other.