JP2007232625A - Electronic timepiece with ring-like solar cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic timepiece with a thin ring-like solar cell which obtains a desired electromotive force, without causing an energy loss in the solar cell. <P>SOLUTION: The electronic timepiece with the ring-like solar cell collects light transmitted through a parting ring to be photoelectric-transferred in the ring-like solar cell, by optically bonding the ring-like solar cell along an outer circumference of the parting ring arranged between a wind shield glass plate and a dial plate. A lower electrode, a photoelectric transfer layer, an upper electrode, and an insulating protection layer with a surface having adhesiveness after cured, are sequentially formed on a flexible substrate, and the parting ring is optically bonded to the ring-like solar cell, by a bonding face formed on a surface of the insulating protection layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  In the present invention, a ring-shaped solar cell is optically bonded to the outer periphery of a parting ring arranged between a windshield and a dial, and light passing through the parting ring is collected and photoelectrically converted by the ring-shaped solar cell. The present invention relates to an electronic timepiece with a ring-shaped solar cell.

  Since an electronic timepiece with a solar battery converts light energy into electric energy and uses it for timepiece driving, there is no concern that the driving suddenly stops due to battery consumption in a general quartz timepiece. Moreover, since it is possible to continue power generation as long as there is light energy, it is not necessary to replace the battery. For this reason, no waste battery is generated from the timepiece, and this electronic timepiece has advantages such as a low environmental burden.

  Usually, the structure of an electronic timepiece with a solar cell used has been arranged with the solar cell exposed on the dial or a solar cell on the back of the dial in order to obtain much power generation efficiency. Since the dial in this structure needs to be transparent or translucent, the dial material is limited. In addition, since it is necessary to guide sufficient light to the solar cell, a design that inhibits light transmission cannot be added to the dial surface. In other words, the conventional electronic timepiece with a ring-shaped solar cell is restricted by the design of the dial.

  Therefore, a ring in which a photoelectric conversion layer is formed on a strip-like flexible resin substrate at the outermost peripheral portion of the dial in the gap between the windshield and the dial with emphasis on the design of the dial. An electronic timepiece structure with a ring-shaped solar cell in which a cylindrical solar cell is installed has been proposed (for example, see Patent Document 1).

  In this conventional electronic timepiece with ring-shaped solar cells, a solar cell is not disposed under the dial, but a ring-shaped solar cell is disposed substantially vertically with respect to the dial at the outermost position of the dial. Therefore, it is not necessary to make the dial described above transparent or translucent. For this reason, for example, a highly reflective metal material can be used as the dial material, or a dial plate having various ink layers on the surface on the viewing side can be used, and an electronic timepiece excellent in design can be obtained.

  In this conventional electronic timepiece with a ring-shaped solar cell, a parting ring having a triangular cross-section is installed on the outer edge of the dial, and the ring-shaped solar cell is arranged with a predetermined gap on the outer edge of the parting ring. Is done. Then, the pointer connected to the movement is moved through the through hole arranged in the center of the dial, and the user uses the electric power stored by the ring-shaped solar cell to see the windshield and time. It can be displayed.

  The structure of the ring-shaped solar cell in the electronic timepiece with the ring-shaped solar cell configured as described above is such that a lower electrode, a photoelectric conversion layer, an upper electrode, and an insulating protective film are sequentially formed on a resin substrate. The surface of the insulating protective film is disposed to face the parting ring. In addition, this insulating protective film can be mainly formed by the screen printing method (for example, refer patent documents 2-6).

JP 2002-148366 A (2nd page, FIG. 1) Japanese Patent Laid-Open No. 10-200133 (page 4, FIG. 1) JP-A-10-270727 (page 4, FIG. 1) Japanese Patent Laid-Open No. 11-97723 (page 4, FIGS. 1 to 4) Japanese Patent Laid-Open No. 11-163379 (page 4, FIGS. 3 to 4) JP 2001-267607 A (5th page, FIG. 1 to FIG. 9)

  However, if a ring-shaped solar cell is installed with a predetermined gap along the outer periphery of the parting ring placed between the windshield and the dial, it exists between the parting ring and the ring-shaped solar cell. The incident light by the air layer is reflected at the interface between the parting ring and the air layer and the interface between the air layer and the ring-shaped solar cell, so that the light use efficiency is reduced. As a result, energy loss of the solar cell is caused. That is, the use efficiency of solar energy is lowered due to the interface between the parting ring and the air layer existing between the ring-shaped solar cells, and a problem that a desired electromotive force cannot be obtained occurs.

  In order to obtain a desired electromotive force, it is conceivable to increase the width of the ring-shaped solar cell to increase the area, but as a result, the thickness of the watch case increases, and the ring-shaped solar cell-equipped electron In a timepiece, it is difficult to provide a timepiece having a thin design aesthetic, which is not preferable.

  Then, this invention solves the said subject, and when installing a ring-shaped solar cell along the outer peripheral part of the parting ring distribute | arranged between the windshield and the dial plate, between this parting ring and a ring-shaped solar cell. To provide a thin electronic watch with a ring-shaped solar cell capable of obtaining a desired electromotive force without reflecting incident light reflected by an interface with an existing air layer and reducing light use efficiency. Objective.

  In order to solve the above problems, the electronic timepiece with a ring-shaped solar cell of the present invention uses the following means.

  The electronic timepiece with a ring-shaped solar cell of the present invention is configured to optically bond a ring-shaped solar cell to the outer periphery of a parting ring disposed between a windshield and a dial plate, thereby collecting light transmitted through the parting ring. In an electronic timepiece with a ring-shaped solar cell that performs photoelectric conversion with a ring-shaped solar cell, a lower electrode, a photoelectric conversion layer, an upper electrode, and an insulating protective film whose surface is adhesive after curing treatment are flexible. The parting ring and the ring-shaped solar cell are optically bonded to each other by the adhesive surface formed on the surface of the insulating substrate and formed on the surface of the insulating protective film.

  The electronic timepiece with a ring-shaped solar cell according to the present invention is characterized in that the insulating protective film is formed of an acrylic photocurable resin.

  Optical bonding here refers to bonding so that no air layer remains between the transparent parting ring in contact with the ring-shaped solar cell, so that light reflection, attenuation, refraction, etc. do not occur at the interface between the two. It means joining.

  By adopting the above configuration and means, when installing a ring-shaped solar cell along the outer periphery of the parting ring placed between the windshield and the dial, insulation protection has adhesiveness on the parting ring and the surface Ring-shaped solar cells with membranes are intimately joined and there is no air layer between them. Therefore, light is not reflected by the interface between the parting ring and the air layer existing between the ring-shaped solar cells, and the light utilization efficiency does not decrease. That is, energy loss in the solar cell is not caused, and use efficiency is not reduced. As a result, a thin electronic timepiece with a ring-shaped solar cell capable of obtaining a desired electromotive force can be provided.

The technology of the electronic timepiece with a ring-shaped solar cell according to the present invention is not limited to a wristwatch, and all electronic devices that can be mounted with a ring-shaped solar cell, such as a pocket watch, a mobile phone, various display devices, a measuring device, a card, and a calculator. Applicable in

  The electronic timepiece with a ring-shaped solar cell of the present invention is obtained by optically bonding the ring-shaped solar cell to the outer periphery of the parting ring arranged between the windshield and the dial, and collecting the light transmitted through the parting ring, In an electronic timepiece with a ring-shaped solar cell that is configured to perform photoelectric conversion with a ring-shaped solar cell, the ring-shaped solar cell has a lower electrode, a photoelectric conversion layer, an upper electrode, and a surface that is adhesive after curing. The insulating protective film employs a structure in which the insulating protective film is sequentially formed on the flexible substrate. Below, the specific structural example of this electronic timepiece with a ring-shaped solar cell is demonstrated in detail.

  First, the configuration of the electronic timepiece with solar cell according to the present invention will be described. Fig.1 (a) shows the front view of the electronic timepiece with a ring-shaped solar cell of this invention, and this figure (b) has shown A-A 'sectional drawing in Fig.1 (a). FIG. 2C shows a perspective view of a ring-shaped solar cell used in the electronic timepiece with the ring-shaped solar cell of the present invention.

  As shown in FIG. 1A, the dial 5 constituting the electronic timepiece with a ring-shaped solar cell of the present invention is circular, and the parting ring 3 is installed on the outermost peripheral portion of the dial 5.

  Moreover, as shown in FIG.1 (b), this electronic timepiece with a ring-shaped solar cell is the windshield 1 attached to the watch case 7, and the clearance gap between the windshield 1 and the dial 5, and this character A translucent parting ring 3 is disposed on the outermost periphery of the plate 5, and is further optically bonded to the outer periphery of the parting ring 3, and the ring-shaped solar cell 2 is disposed without interposing an air layer. As a result, the light transmitted through the windshield 1 and repeatedly reflected between the dial 5 and the windshield 1 or the direct light transmitted through the windshield 1 enters the translucent parting ring 3, and this parting ring 3 can be incident on the ring-shaped solar cell 2 described above. The electric power photoelectrically exchanged by the incident light is stored in a secondary battery (not shown) mounted on the movement 6 disposed under the dial 5.

  Further, the dial 5 is provided with a through-hole that allows the pointer shaft to pass through substantially the center thereof, and a booster circuit for boosting a voltage obtained by a secondary battery (not shown) and the pointer 4 are driven. The pointer 4 can be rotationally driven by the movement 6 having the driving circuit.

  And as shown in FIG.1 (c), this ring-shaped solar cell 2 is circular shape, and the electric power extraction electrodes 8a and 8b for taking out the electromotive force generated with the ring-shaped solar cell 2 are arrange | positioned at both ends. Has been.

  Note that the amount of light for generating the electric power necessary to drive the electronic timepiece and maintain accurate timing varies depending on the conversion efficiency of the ring-shaped solar cell 2 to be used. Therefore, it is necessary to design the upper and lower electrodes and the photoelectric conversion layer constituting the parting ring 3 and the ring-shaped solar cell 2 in accordance with the necessary light quantity that can be collected by the ring-shaped solar cell 2.

  The parting ring 3 used in the present invention is configured by a member designed so as not to attenuate as much as possible the amount of light in the wavelength band that increases the photoelectric conversion efficiency performed in the ring-shaped solar cell 2. Normally, the ring-shaped solar cell 2 used in an electronic watch is designed to have the highest power generation efficiency under a fluorescent lamp. Therefore, the parting ring 3 is designed so that light having a wavelength in the visible light range is not attenuated. ing.

Next, the ring solar cell 2 will be described in detail below. FIG. 2A is a cross-sectional view showing the configuration of the ring-shaped solar cell 2. FIG. 2B is a cross-sectional view showing a state in which the ring-shaped solar cell 2 is optically bonded to the parting ring 3.

  As shown in FIG. 2 (a), the ring-shaped solar cell 2 used in the electronic timepiece with solar cell of the present invention is a flexible resin substrate made of a PET (polyethylene terephthalate) film or a PEN (polyethylene naphthalate) film. 10, a lower electrode 11 made of Al or Ti, a photoelectric conversion layer 12 made of an amorphous silicon layer, an upper electrode 13 made of ITO (indium tin oxide), and a surface that is adhesive after curing. A structure in which an insulating protective film 14 having layers is sequentially laminated is employed. Note that the junction structure of the photoelectric conversion layer 12 may be any configuration such as a pin junction structure, a pn junction structure, a heterojunction structure, a Schottky structure, and a multiple junction structure. Thereafter, although details are omitted, the photoelectric conversion layer 12 and the upper electrode 13 are formed in the same pattern by employing a photolithography method and a dry etching method.

  Next, the insulating protective film 14 formed on the upper electrode 13 of the ring-shaped solar cell of the present invention and having a sticky surface after the curing process will be described. As shown in FIG. 2A, the insulating protective film 14 is formed on the upper electrode 13, but in the present invention, an acrylic photocurable resin is formed by a screen printing method. The reason for selecting the acrylic photocurable resin is as follows.

  In this invention, as shown in FIG.2 (b), reflection of incident light in the interface with the air layer between the parting ring 3 and the ring-shaped solar cell 2 is lost, and the energy loss of the solar cell is caused. In addition, in order to provide a thin electronic watch with a ring-shaped solar cell capable of obtaining a desired electromotive force, along the outer peripheral portion of the parting ring 3 disposed between the windshield glass 1 and the dial plate 5. When installing the ring-shaped solar cell, it is necessary to optically bond the parting ring 3 and the ring-shaped solar cell 2 having the insulating protective film 14 having a sticky surface after the curing process to eliminate the air layer existing between them. .

  As a result of studying various materials by the inventor as the insulating protective film 14 for that purpose, it has been found that an acrylic photocurable resin is optimal. Usually, an acrylic photo-curing resin is difficult to be photo-cured in the presence of oxygen due to a curing inhibition reaction by oxygen. Therefore, photocuring is performed in an inert gas atmosphere that does not contain oxygen such as nitrogen gas. However, slight adhesiveness called tack remains on the resin surface. In the present invention, the adhesiveness remaining on the surface is used for optical adhesion in a state in which the air layer existing between the parting ring 3 and the ring-shaped solar cell 2 having the insulating protective film 14 is eliminated.

  The acrylic photo-curing resin can be formed by a screen printing method, but may be another coating method such as a spin coating method. Also, the film thickness of the insulating protective film 14 made of acrylic photo-curing resin is suitably 10 μm to 100 μm. When the thickness is 10 μm or less, it is difficult to obtain sufficient insulation, and when the thickness is 100 μm or more, the surface of the insulating protective film 14 is conspicuous and warping due to stress becomes remarkable, which causes the clearance between the parting ring 3 and the insulating protective film 14. This is because the air layer may be interposed again.

Although it is difficult to numerically evaluate the adhesiveness of the surface of the insulating protective film 14 made of an acrylic photo-curing resin, it has sufficient adhesiveness to optically adhere to the parting ring. Further, it is preferable to apply a pressure of about 1 kgf / cm ² or more for optical adhesion. In that case, if it is performed in an atmosphere of about 50 ° C. or higher, a stronger bonding force can be obtained. Further, in the present invention, the electronic timepiece with a ring-shaped solar cell in which the dial 5 has the circular dial 5 (see FIG. 1A) has been described. However, the present invention is not limited to this. It can also be applied to a deformed dial such as a square.

Thus, according to the configuration of the present invention, the ring-shaped solar cell 2 having the parting ring 3 and the insulating protective film 14 having a sticky surface after the curing treatment is closely optically bonded, and an air layer exists between them. Therefore, it is possible to provide a thin electronic watch with a ring-shaped solar cell capable of obtaining a desired electromotive force without causing reflection of incident light from the air layer interface and causing no energy loss of the solar cell. It becomes.

It is drawing which shows the structural example of the electronic timepiece with a ring-shaped solar cell of this invention. It is sectional drawing which shows the structure of the ring-shaped solar cell in the electronic timepiece with a ring-shaped solar cell of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Windshield 2 Ring-shaped solar cell 3 Parting ring 4 Pointer 5 Dial 6 Movement 7 Watch case 8a, 8b, Power extraction electrode 10 Substrate 11 Lower electrode 12 Photoelectric conversion layer 13 Upper electrode 14 Insulating protective film

Claims (2)

A ring-shaped solar cell is optically bonded to the outer periphery of the parting ring placed between the windshield and the dial so that light passing through the parting ring is collected and photoelectrically converted by the ring-shaped solar cell. In an electronic watch with a ring-shaped solar cell,
The ring-shaped solar cell is formed by sequentially forming a lower electrode, a photoelectric conversion layer, an upper electrode, and an insulating protective film having a sticky surface after curing treatment on a flexible substrate,
An electronic timepiece with a ring-shaped solar cell, wherein the parting ring and the ring-shaped solar cell are optically bonded by an adhesive surface formed on the surface of the insulating protective film. 2. The electronic timepiece with a ring-shaped solar cell according to claim 1, wherein the insulating protective film is formed of an acrylic photocurable resin.

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