JP2002267771A - Timepiece with solar cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a timepiece with solar cell equipped with a dial having a reflecting sheet capable of making the dark violet color peculiar to a solar cell inconspicuous from the outside and facilitating the formation of a minute through-hole at a low cost. SOLUTION: In a timepiece dial 21 equipped with a light transmitting dial body part 22 above the solar cell 24, an elastic reflecting sheet 23 comprising a metal film 42 evaporated on an elastic sheet member 41 and having a number of minute through-holes 43 100 μm or less in diameter is arranged on the lower surface of the dial body part 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a timepiece provided with a solar cell.

[0002]

2. Description of the Related Art A timepiece dial 1 as shown in FIG. 6 has been conventionally known as a display unit of a timepiece with a solar cell driven by solar power generation (see Japanese Patent Application Laid-Open No. H11-326549). The timepiece dial 1 includes a dial main body 2 having light transmissivity and a solar cell 3. A metal film 5 having a large number of small through-holes 4 formed on the upper surface of the dial body 2 is provided. The solar cell 3 is charged by taking in external light from the small through-holes 4 and reflected by the metal film 5. The emitted light brightens the dial body 2. The letter character 6 is provided time on the metal film 5, and further protect the metal layer 5 and the dial body portion 2 to form a transparent coating layer 7 thereon.

[0003]

The smaller the small through-holes 4 formed in the metal film 5, the smaller the fine purple color peculiar to the solar cell becomes less conspicuous through the dial body 2. However, such a minute through-hole cannot be provided by a mechanical processing method. For this reason, in the conventional timepiece dial 1, the minute through holes 3 are provided in the metal film 5 by a photo etching method. This metal film 4 is formed by first printing a resist film on a metal plate such as stainless steel, arranging a negative film on which a pattern of holes is formed on the resist film, exposing the film to ultraviolet light, and exposing the holes. The resist film other than the corresponding portion is peeled off. Next, a release agent is applied to a portion where the resist film has been stripped, and thick electroplating is performed on the portion where the resist film has been stripped. Then, the remaining resist film is peeled off, and finally, the electroformed plating is peeled off from the stainless metal plate to form the metal film 4 in which the minute through holes 3 are formed. In such a photo-etching method, although a minute through-hole can be formed with high accuracy, there is a problem in that the above-described large number of steps are required, and thus the manufacturing cost is relatively high. Further, since a substance harmful to the human body such as a resist stripping solution is used in the manufacturing process, it is not preferable in terms of environment and hygiene.

Accordingly, the present invention provides a timepiece with a solar cell equipped with a dial with a reflective sheet, which makes it possible to form a minute through hole at a simple and low cost while making the dark purple characteristic of the solar cell inconspicuous from the outside. is there.

[0005]

According to a first aspect of the present invention, there is provided a timepiece with a solar cell, wherein the timepiece includes a dial main body having a light transmitting property above the solar cell. An elastic reflection sheet having a large number of minute through holes is provided on one of the upper surface and the lower surface of the dial body.

According to the present invention, the elastic reflection sheet provided with a large number of minute through holes is arranged in parallel with the solar cell on either the upper surface or the lower surface of the dial body, so that the dark purple color unique to the solar cell is provided. In addition to being less noticeable, power generation and charging can be performed by effectively taking in external light.
In addition, when the surroundings are bright, such as during the daytime, external light can be reflected by the elastic reflection sheet to brighten the dial body surface.

[0007] The invention according to claim 2 is characterized in that the minute through holes are formed to have a diameter of 100 µm or less.

According to the present invention, since one micro through hole provided in the elastic reflection sheet is finely processed to have a diameter of 100 μm or less, the shape of the hole is not conspicuous, and the external decorativeness is not impaired. Further, since a large number of such minute through holes are formed, sufficient light transmittance can be ensured.

[0009] The invention according to claim 3 is characterized in that the minute through holes are arranged in a matrix.

According to the present invention, since the minute through holes are regularly arranged in a matrix, external light is transmitted uniformly through the solar cell without unevenness, so that sufficient photoelectric conversion can be performed.

According to a fourth aspect of the present invention, the minute through hole is provided by stretching an elastic sheet member having a predetermined cross-sectional shrinkage rate into a plate shape to form a large number of processing holes, and then contracting the original shape. It is characterized by having been done.

According to the present invention, several hundred μm opened by using a mechanical processing method such as pressing or laser processing.
Can easily be formed as minute through holes of 100 μm or less. In addition, since there is no need to use a manufacturing method that requires many steps such as photo etching,
The product cost is reduced, and it can be used for relatively low-cost watches.

The invention according to claim 5 is characterized in that the elastic reflection sheet is formed by applying either a metal film or a colored coating film to the elastic sheet member.

According to the present invention, since the metal film or the colored coating film is formed on the surface of the elastic sheet member, the dark purple color unique to the solar cell can be made inconspicuous.
In addition, when external light is reflected, the decorativeness of the display surface of the display device can be enhanced with a metal color or other various colors.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a timepiece with a solar cell according to the present invention. FIG. 1 is a sectional view of a solar cell watch with a solar cell according to a first embodiment of the present invention, FIG. 2 is an enlarged sectional view of an elastic reflection sheet, and FIG. 3 is an enlarged plan view of the elastic reflection sheet.

As shown in FIG. 1, the timepiece with solar cell according to the first embodiment has an analog timepiece dial 21.
It is. The timepiece dial 21 includes a dial body 22
And an elastic reflection sheet 23 and a solar cell 24. The dial main body 22 has light transmissivity, and is made of polycarbonate resin or the like, which is a material relatively frequently used for dials for watches. The color of the dial body 22 is preferably transparent so as to ensure sufficient light transmittance,
It may be lightly colored. In addition, a hole 26 through which the pointer shaft passes is provided at the center of the dial body 22 and an hour character 25 is provided around the center, and various patterns are formed on the surface. This pattern pattern can be formed in an uneven shape that does not reduce the light transmittance, a lattice shape, a cycle shape, a stripe shape, other geometric shapes, and the like.

As shown in FIGS. 2 and 3, the elastic reflection sheet 23 disposed on the lower surface side of the dial body 22 has
A thin metal film 42 is coated on an elastic sheet member 41 made of silicon rubber, and a large number of minute through holes 43 are provided on the surface. The elastic sheet member 41 includes:
Thickness ranging 100 to 300 [mu] m, the cross-sectional shrinkage 2-8
It is preferably about twice. By using the elastic sheet member 41 having such a cross-sectional shrinkage rate, as described later, a large number of through holes are opened in the state where the elastic sheet member 41 is horizontally extended, and the elastic sheet member 41 is returned to its original state. When contracted into a shape, it becomes possible to form a large number of minute through holes 43 having a diameter of 100 μm or less.

The metal film 42 coated on the elastic sheet member 41 is formed by evaporating nickel, aluminum, silver, gold or the like. The minute through hole 43
Is a hole penetrating the metal film 42 and the elastic sheet member 41, and the diameter thereof is set to 100 μm or less. By setting the thickness to 100 μm or less, the minute through-holes 43 are hardly conspicuous when the dial main body 22 is provided with a pattern or a light color. When the diameter of the minute through-hole 43 is larger than 100 μm, the hole itself becomes conspicuous and the appearance is not good. Also,
The minute through-holes 43 are arranged in a matrix at regular intervals on the entire surface of the elastic reflection sheet 23, and the area ratio of all the openings of the minute through-holes 43 is determined in consideration of the light transmittance. Is set to 20 to 50% with respect to the area of. When the area ratio of the opening is smaller than the set value, the amount of power generation for driving the timepiece is not ensured. On the contrary, when it exceeds the set value, the dark purple color peculiar to the solar cell 24 appears and impairs the appearance. The timepiece dial 21 shown in FIG. 1 incorporates the elastic reflection sheet 23 in a state where a metal film 42 is bonded to the lower side of the dial main body 22. Therefore, when the dial main body 22 is viewed from above, the dark purple color unique to the solar cell 24 is hidden, and appears to shine in a metallic color.

The solar cell 24 has a structure in which an insulating layer, a lower electrode layer, a solar cell, and a transparent electrode layer are laminated on a substrate. The solar cell receives light incident through the uppermost transparent electrode layer. To generate the electric power necessary for driving the clock. This solar cell 24 is the elastic reflection sheet 23
It is arranged below.

In addition, a hole 26 for passing the pointer shaft is provided at the center of the elastic reflection sheet 23 and the solar cell 24. The elastic reflection sheet 23 is disposed in a state where the surface on which the metal film 42 is formed is joined to the back surface of the dial body 52.

Next, a procedure for forming the elastic reflection sheet 23 will be described. Silicon rubber, which is a material of the elastic sheet member 41, is formed in a predetermined shape, size and thickness. The shape and size are processed according to the dial main body 22, and the thickness is set to 100 to 300 μm. The formed elastic sheet member 41 is horizontally stretched to several times its original size. Although the stretching magnification is determined by the cross-sectional shrinkage of the silicone rubber used, about 2 to 8 times is appropriate. In the present embodiment, a silicone rubber having a cross-sectional shrinkage of about twice is used. A large number of through holes are formed at equal intervals in the stretched elastic sheet member 41 by pressing or laser processing. The diameter of the through hole to be opened at this time is set to 200 μm corresponding to the cross-sectional shrinkage of the silicone rubber. The stretched elastic sheet member 41 is contracted to its original size. The diameter of the through hole in this state is about 10
It is about 0 μm. A metal film 42 is deposited on one surface of the elastic sheet member 41 to form the elastic reflection sheet 23. The above embodiment is an example in which the diameter of the fine through-hole is 100 μm. However, when a finer through-hole is formed, a hole is formed by using an elastic sheet member having a large sectional shrinkage. Perform processing.

The timepiece dial 31 shown in FIG. 4, but according to a second embodiment of the present invention is obtained by placing the elastic reflection sheet 23 of FIG. 1 on the upper surface of the dial body 22.
As described above, in the structure in which the elastic reflection sheet 23 in which the metal film 42 is formed on the upper surface side is placed on the upper surface of the dial main body 22, the dark purple color unique to the solar cell 24 is used.
With hidden by the elastic sheet member 41 and the metal film 42, the timepiece dial having a metallic feeling by the metal film 42 is brought into direct contact with eye can be obtained. Further, when a transparent clear layer 37 is formed on the surface of the elastic reflection sheet 23, the metal film 4
2 can be protected, and a clear reflection effect can be obtained over a long period of time.

A timepiece 51 shown in FIG. 5 relates to a third embodiment of the present invention, and includes a light-transmissive display section 52 composed of a liquid crystal display element and a dial, a light reflection section 53, and a solar cell 24 for power generation. , Each of which is manufactured separately. The light reflecting portion 53 is formed by joining the elastic reflecting sheet 23 formed by the structure and the manufacturing method shown in the first and second embodiments to a transparent plastic plate 54. Since the light reflecting portion 53 provided with such an elastic reflecting sheet 23 is formed separately, the combination of the display portion, the solar cell, and the like can be changed in the assembly process of the timepiece. In addition, since they can be independently and collectively manufactured, the number of manufacturing steps and cost can be reduced.

The method of manufacturing the elastic reflection sheet according to the second and third embodiments can be manufactured by a method similar to that of the elastic reflection sheet 23 according to the first embodiment. The metal film 42 provided on the elastic sheet member 41 is for producing a metal color such as silver or gold. However, in order to obtain other colors such as red and blue, instead of the metal film 42, The coating layer of each color is applied to the elastic sheet member 41.
What is necessary is just to apply | coat and form.

In each of the above-described embodiments, an example in which the present invention is applied to a timepiece dial for performing analog display is described. The invention can be applied to any electronic device having a relatively large display screen.

[0026]

As described above, according to the timepiece with solar cell according to the present invention, the elastic reflection sheet having a large number of minute through-holes can be connected to either the upper or lower surface of the dial body by using the solar cell. In addition to making the dark purple color unique to the solar cell inconspicuous, power generation and charging can be performed by effectively taking in external light. In addition, when the surroundings are bright, such as during the daytime, external light can be reflected by the elastic reflection sheet to brightly illuminate the dial body surface.

Further, since the minute through-holes provided in the elastic reflection sheet are finely processed to have a diameter of 100 μm or less, the shape of the holes is not conspicuous, and the external decorativeness is not impaired. Further, since a large number of such minute through holes are formed, sufficient light transmittance can be ensured.

Further, since the small through-holes are regularly arranged in a matrix, external light is uniformly transmitted through the solar cell without unevenness, so that sufficient photoelectric conversion can be performed.

Further, when a minute through hole is provided in the elastic sheet member, a through hole having a diameter corresponding to the cross-sectional shrinkage of the elastic sheet member may be formed. It is possible to easily form a through hole of several hundred μm opened by using as a minute through hole of 100 μm or less. Therefore, the number of manufacturing steps and cost can be reduced.

Further, since a metal film or a colored coating film is formed on the surface of the elastic sheet member, the dark purple color peculiar to the solar cell is made inconspicuous, and the decorativeness of the dial with the metal color or other various colors is improved. Can be enhanced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a first embodiment of a timepiece with solar cells according to the present invention.

FIG. 2 is an enlarged sectional view of the elastic reflection sheet shown in FIG.

FIG. 3 is an enlarged plan view of the elastic reflection sheet shown in FIG.

FIG. 4 is a sectional view of a second embodiment of the timepiece with solar cell of the present invention.

FIG. 5 is a sectional view of a third embodiment of the timepiece with solar cell of the present invention.

FIG. 6 is a cross-sectional view of a conventional solar cell watch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Watch dial 22 Dial main body 23 Elastic reflection sheet 24 Solar cell 41 Elastic sheet member 42 Metal film 43 Micro through hole

Claims (5)

[Claims] 1. A timepiece having a dial main body having light transmissivity above a solar cell, wherein an elastic reflection having a large number of minute through holes formed on one of an upper surface and a lower surface of the dial main body. A solar cell watch with a seat. 2. The solar cell-equipped timepiece according to claim 1, wherein the minute through-hole has a diameter of 100 μm or less. 3. The solar cell-equipped timepiece according to claim 1, wherein the minute through-holes are arranged in a matrix. 4. The micro through hole is formed by stretching an elastic sheet member having a predetermined cross-sectional shrinkage rate into a plate shape to form a large number of processing holes, and then shrinking the original shape. The solar cell-equipped timepiece according to any one of claims 1 to 3, wherein: Wherein said elastic reflection sheet, timepiece solar cell according to any one of claims 1 to 4, characterized in that said one of the elastic sheet member on a metal film or a colored paint film formed by coating.