JPH07124044A - Anti-fog mirror - Google Patents

Abstract

PURPOSE:To indicate a pattern with a cloudy background formed with water drops, by providing a heat-transfer plate having an almost similar shape to the pattern shape and a heat generating substance composed of a positive-characteristic thermister in the inside and equipped a heater electrically insulated as a whole and providing a heat-transfer plate close to the rear face of a mirror, and further, providing a heater at the rear of the heat-transfer plate. CONSTITUTION:When conducting currents to a heater 4, since the heater 4 is provided with a heat generating substance 5 composed of a positive characteristic thermister as a heat-generating means, the temperature of the heater rises rapidly up to a specified temperature after conduction of current. The heat generated by the heater 4 equipped at the rear face of the heat-transfer plate 2 is transferred to the surface of mirror through the heat-transfer plate 2. When continuously conducting current to the heater 4, the face with which the heat-transfer plate 2 gets in contact is heated and water drops are evaporated to remove the cloud. The portion on the mirror, where the heat generated by the heater 4 is not transferred, is not heated and hence the temperature does not rise. Accordingly, the water drops are left and the cloud is kept, thus a specified pattern is indicated on the contact part of the heat-transfer plate on the surface of mirror 1, with the cloudy background.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-fog mirror in which a predetermined pattern can be displayed on a mirror clouded with water drops.

[0002]

2. Description of the Related Art Generally, a display portion is provided on the surface of a mirror installed in a place with high humidity such as a bathroom or a wash basin, and the display portion is painted with, for example, letters or figures for advertising or decoration, or a picture. Mirrors with a display unit drawn by the above are widely known. However, in the above-described conventional mirror with a display unit, characters, figures, pictures, etc. are drawn on the display unit provided on the surface of the mirror with paint or the like, so that this display unit loses its function as a mirror. That is, when the display portion is provided on the surface of the mirror, there is a problem that the area actually usable as the mirror is reduced.

Therefore, the applicant of the present invention is a mirror having a display portion on the surface of the mirror and capable of displaying a predetermined symbol on a mirror clouded by water droplets, the convex portion having a shape substantially equal to the shape of the symbol. A heat transfer plate having a part formed on the surface, a heating element made of a positive temperature coefficient thermistor inside, and a heater entirely covered with an electrically insulative coating material, and the pattern on the back surface of the display part. A mirror with a display unit having a structure in which a heat transfer plate is provided in close contact and the heater is fixed to the back surface of the heat transfer plate is proposed (Japanese Patent Application No. 5-39529).

[0004]

According to this mirror with a display unit, the heat generated by the heater corresponds to the portion where the convex portions of the heat transfer plate in the display unit are in close contact with each other via the heat transfer plate. It is transmitted only to the part, the display part retains the function as a mirror, the fog is eliminated in a shape equal to the shape of the convex part of the heat transfer plate, and the above symbol can be displayed against the background of the fog caused by water droplets. The symbol can be displayed on the surface of the mirror without reducing the area that can be used as a mirror, and can repeatedly draw the attention of the user of the mirror. However, the display shown on this display portion is limited to a predetermined symbol having the same shape as the convex portion of the heat transfer plate.

[0005]

In order to solve the above-mentioned problems, the anti-fog mirror of the present invention eliminates fog in a shape almost equal to a predetermined pattern on a mirror fogged with water droplets due to dew condensation. An anti-fog mirror configured to display a pattern as a background, and a heat transfer plate having a planar shape substantially equal to the shape of the pattern,
A heat generating element made of a positive temperature coefficient thermistor is provided inside, and a heater entirely covered with an electrically insulating coating material is provided, and the heat transfer plate is provided in close contact with the rear surface of the mirror. Is characterized in that the heater is provided on the back surface of the.

[0006]

According to the above construction, the heater, which internally has a heating element composed of a positive temperature coefficient thermistor and is entirely covered with an electrically insulative coating material, rapidly rises in temperature to a predetermined temperature after being energized, and has a predetermined temperature. When the temperature is reached, it will be maintained. On the other hand, on the heat transfer plate closely attached to the back of the mirror,
The planar shape is substantially the same as the pattern shape, and the heater is closely attached and fixed to the back surface of the heat transfer plate. Therefore, the heat generated by the heater is transferred only to the heat transfer plate having a planar shape substantially equal to the design. That is, the mirror is heated only at the portion where the heat transfer plate having a shape substantially equal to the shape of the design is in contact.

Therefore, in the mirror fogged by water drops, only the heat transfer plate portion to which the heat generated by the heater is transferred is warmed to evaporate the water drops and eliminate the fog, but the above heat is not transferred. Since the part cannot be heated, water drops will remain and it will remain cloudy. Therefore, since the fogging of only the heat transfer plate portion having the same planar shape as the design is eliminated,
A pattern corresponding to the shape of the heat transfer plate will be displayed against the background of cloudiness caused by water drops. Further, the mirror does not display a symbol, for example, when the heater is not energized. As a result, it is possible to display the design while maintaining the function as a mirror. That is, the pattern can be displayed on the surface of the mirror against the background of cloudiness without reducing the area that can be used as the mirror.

Further, according to the above construction, the mirror, which is seemingly innocent at first glance, displays the pattern when it is fogged by water droplets, so that it can be repeatedly noticed by the user of the mirror. . Also, for example, when a design is provided for advertising, the advertising effect can be enhanced.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following will describe one embodiment of the present invention with reference to FIGS.

As shown in FIGS. 1 and 2, the mirror with a pattern according to the present embodiment has a predetermined position on the rectangular mirror 1, for example, a central portion of the rear surface of the mirror 1 at a predetermined position on the surface of the mirror 1. As will be described later, in order to display a pattern by the anti-fog function, a heat transfer plate 2 having a planar shape substantially equal to the shape of a dinosaur (here, stegosaurus) is provided in close contact. Since the heat transfer plate 2 has a heat transfer function, it is formed of a metal having excellent heat conductivity, such as copper, phosphor bronze, aluminum or stainless steel. A plurality of heaters 4 ... Are attached to the rear surface of the heat transfer plate 2 at predetermined intervals. The heaters 4 are attached to the heat transfer plate 2 by sticking them together with an adhesive or the like, and one surface of the heater 4 is in close contact with the back surface of the heat transfer plate 2.

The thickness of the heat transfer plate 2 is not particularly limited, but may be about 3 to 4 mm so that the mirror 1 main body can be installed on a wall or the like. The thickness of the mirror 1 is not particularly limited, but may be about 5 mm so that a predetermined symbol can be clearly displayed on the display unit 1a as described later. Further, the sizes of the mirror 1 and the display unit 1a are not particularly limited as long as the design can be clearly displayed.

As shown in FIG. 3 and FIG. 4, the heater 4 has a heating element 5, metal terminals 8 and 8, lead wires 9 and 9 serving as a power feed line, and an insulation formed of an electrically insulating coating material. It is composed of a case 10.

The heating element 5 has a positive temperature coefficient (Positive Tempe).
a ceramics semiconductor whose main raw material is barium titanate or the like,
It is a positive temperature coefficient thermistor as a heat sensitive element having a characteristic that it has a low resistance from room temperature to the Curie temperature Tc (rapid change temperature), but its resistance value sharply increases when it exceeds the Curie temperature Tc. Due to this characteristic, when a voltage is applied to the heating element 5, the resistance value is small at first and a large current flows due to the low temperature, and as a result, the temperature rises rapidly.
When the temperature exceeds the Curie temperature Tc, the resistance value sharply increases, so that the temperature does not rise above a certain temperature and the certain temperature is kept stable. That is, the heating element 5 can have a self-temperature control function. Therefore, the heater 4
Consumes less power, can omit the temperature control circuit and overheat prevention circuit, and can be downsized. Further, there is no fear of ignition due to local overheating, noise is not generated, and even if electricity is constantly energized, there is almost no electricity bill.

The Curie temperature Tc of the heating element 5 can be arbitrarily set within the range of about 30 to 250 ° C. depending on the material composition. Therefore, in the heating element 5 according to the present embodiment, for example, safety and power saving are taken into consideration so that an antifogging function is given to the surface of the mirror 1 and a temperature effective for displaying a symbol can be realized. The Curie temperature Tc may be set.

The heating element 5 has a flat disk shape,
As shown in FIG. 4, electrodes 5a, 5a formed by applying, for example, silver paint, are provided on the upper and lower surfaces.

The metal terminal 8 is in the form of a circular flat plate having a diameter substantially equal to the outer diameter of the heating element 5. Further, each metal terminal 8 is formed with a power feeding portion 8a for connecting the lead wire 9. These power supply portions 8a, 8a are parallel to each other and extend in the introduction direction of the corresponding lead wires 9, 9.

The electrical connection between the heating element 5 and the metal terminals 8 and 8 is made by attaching the electrode 5a of the heating element 5 and the metal terminal 8 with a conductive adhesive of, for example, an epoxy resin / silver mixture. Has been done. In addition, the power feeding portions 8a, 8a and the lead wire 9
The electrical connection with 9 is made by, for example, soldering the corresponding lead wires 9 to the facing surfaces of the power supply portions 8a and 8a.

The insulating case 10 is composed of an insulating case lower portion 10a as a covering substrate and an insulating case upper portion 10b. The insulating case 10 covers and heats the heating element 5 and the metal terminals 8 and 8; In addition, the insulating case 10 has a terminal portion on the metal terminal 8 side of the lead wires 9 and 9 so that a mechanical load is not applied to a soldered portion of the lead wire 9 and the power feeding portion 8a of the metal terminal 8 to prevent disconnection. It is also designed to cover.

The insulating case 10 has a heating element 5 and the like housed in an insulating case lower portion 10a which is preformed by injection molding or the like, and is installed in an injection molding die (not shown), and then the insulating case upper portion 10b. The insulating case lower portion 10a and the insulating case upper portion 10b are integrally formed by injection-molding a partial plastic. As a result, the heating element 5 and the like are sealed and fixed inside the insulating case 10.

The insulating case 10 has a small heat shrinkage rate, is excellent in thermal conductivity and mechanical strength, is heat resistant to withstand the heat generation temperature of the heating element 5, is waterproof and does not allow moisture such as water vapor to pass through inside. It is necessary that the lead wire 9 and 9 have good airtightness and that the lead wires 9 and 9 have good adhesion to the coating material. For example, a polymer alloy made of polyamide, polypropylene and glass fiber, or the like may be used. ing.

The lead wires 9 and 9 connected to each heater 4 are connected to the junction member 1 as shown in FIG.
2 is connected to a power cord 13 having a plug (not shown) or the like at its tip, and is electrically connected to an outlet (not shown) which is an external power source through the power cord 13. . Therefore, the heaters 4 are connected in parallel with each other. The junction member 12 ...
Is attached to the back surface of the heat transfer plate 2 with an adhesive or the like.

Fixing device 1 made of metal or synthetic resin so that the lead wires 9 and the power cord 13 are not loosened.
It is fixed to the back surface of the mirror 1 by 4 ... The fixing tools 14 ... Are attached to the rear surface of the mirror 1 by adhering the both with an adhesive or the like.

In the above heater 4, the metal terminal 8
The lead wires 9 are respectively provided on the facing surfaces of the power feeding portions 8a and 8a of FIG.
By connecting .9, unevenness due to the connection of the lead wires 9.9 does not occur on the outer surface side of the metal terminals 8. Therefore, the thickness for absorbing this unevenness is set to the insulating case 10.
The insulating case 10, that is, the heater 4 can be thinly formed. As a result, the heater 4 can be made smaller, thinner, and lighter in weight, can be mounted on the back side of the mirror 1, and can efficiently transfer the heat generated by the heating element 5 to the heat transfer plate 2. it can. The above heaters 4 are manually turned on by a switch (not shown).
It is designed to be turned off.

First, for example, when a shower is used to increase the humidity and fine water droplets adhere to the surface of the mirror 1, the entire surface of the mirror 1 becomes cloudy. At this time, the heaters 4 are not energized, and nothing is displayed on the surface of the mirror 1.

In this state, turn on a switch (not shown)
However, when the heater 4 is energized, the heater 4 uses the heating element 5 composed of a positive temperature coefficient thermistor as a heating means. Therefore, after the energization, the temperature rapidly rises to a predetermined temperature, and when the predetermined temperature is reached, the It will keep the temperature. Therefore,
The heat generated by the heaters 4 provided on the back surface of the heat transfer plate 2 is transferred to the surface portion of the mirror 1 via the heat transfer plate 2.

When the heaters 4 are further energized, as shown in FIG. 5, the portion of the surface of the mirror 1 which is in contact with the heat transfer plate 2 is warmed to evaporate water droplets and eliminate the fog (prevention). Cloudy function). On the other hand, the part of the surface of the mirror 1 to which the heat generated by the heaters 4 is not transferred is not warmed and the temperature does not rise, so that water drops remain and the cloudy state is maintained.

Therefore, at the heat transfer plate contact portion on the surface of the mirror 1,
As shown in FIG. 5, a predetermined symbol is displayed against the cloudy background. For example, a face or the like can be clearly displayed in the displayed pattern in which the cloudiness is eliminated.

Incidentally, after the energization of the heaters 4 ...
The time until the mirror 1 clearly displays the design can be arbitrarily set by changing the Curie temperature Tc of the heating element 5, but in order to make the design more effective, heat diffusion and the like are considered. Therefore, it is preferable that the length is shorter, for example, about 2 minutes.

Further, according to the above-mentioned structure, the mirror 1 which is seemingly stable at first glance attracts the attention of the user of the mirror 1 because of the unexpectedness that the pattern is displayed when it is fogged by water droplets. it can. Thereby, for example, when a design is provided for advertising, the advertising effect can be enhanced.

In the above embodiment, the dinosaur picture is taken as an example of the design to be displayed, but of course the displayed design is not limited to the above design. Also,
In the above-described embodiment, the number of heaters 4 fixed to the heat transfer plate 2 and the arrangement of the heaters 4 ... May be appropriately changed according to the size of the heat transfer plate 2. And the heater 4
The shape of the heating element 5 is not limited to the flat disk shape or the circular flat plate shape described above, and may be various shapes such as a square plate shape.

In the above embodiment, the case where the heater 4 having one heating element 5 inside is used has been described as an example, but the number of heating elements 5 provided inside the heater is one. It is not limited to the above, but a plurality may be provided. In this case, the number of heating elements 5 provided inside the heater is equal to the number of heat transfer plates 2
It may be appropriately changed according to the size of the mirror 1 or the like. When a heater provided with a plurality of heating elements 5 is used, the number of lead wires 9 is reduced, so that it becomes easy to connect the lead wires 9 to each other by the junction members 12, and the heater to the heat transfer plate 2 is connected. Installation is also simplified. The heating elements 5 provided in the heater may be electrically connected in parallel with each other by, for example, a pair of metal terminals.

Furthermore, in the above embodiment, the heat transfer plate 2 has a planar shape of stegosaurus, but the heat transfer plate 2 has a shape of
Of course, the shape is not limited to Stegosaurus, and may be various shapes such as other dinosaurs and animals.
Further, in the above-described embodiment, the case where the heater 4 is formed in a flat disk shape has been described as an example, but the heating element 5 is used.
The shape of the heater 4 is not limited to the above-described embodiment as long as it can efficiently transfer the heat generated in (1) to the heat transfer plate 2, and may be, for example, a rectangular parallelepiped shape.

[0033]

As described above, the anti-fog mirror of the present invention has a heat transfer plate having a shape substantially equal to the shape of the design and a heating element composed of a positive temperature coefficient thermistor inside, and is entirely electrically insulating. A heater coated with a coating material is provided, the heat transfer plate is provided in close contact with the back surface of the mirror, and the heater is provided on the back surface of the heat transfer plate.

Therefore, the heat generated by the heater is transferred only to the mirror surface portion corresponding to the portion where the heat transfer plate having a shape substantially equal to the shape of the design is in close contact with the heat transfer plate. Therefore, in the mirror fogged by water droplets, only the part where the heat generated by the heater is transferred is contacted by the heat transfer plate is warmed and the water droplets evaporate, and the shape corresponding to the shape of the heat transfer plate becomes cloudy. On the other hand, the above-mentioned area where heat is not transferred cannot be warmed up, so that water drops remain and the cloudy state is maintained. As a result, the above-mentioned pattern is displayed against the background of cloudiness caused by water droplets. It should be noted that the mirror does not display a symbol, for example, when the heater is not energized.
As a result, the pattern can be displayed while maintaining the function as a mirror. That is, it is possible to display a pattern on the surface of the mirror without reducing the area that can be used as the mirror.

Further, according to the above-mentioned structure, the mirror, which is seemingly innocent at first glance, displays the pattern when it becomes cloudy due to water droplets, so that the user of the mirror can repeatedly receive the attention. . Thereby, for example, when a design is provided for advertising, the advertising effect can be enhanced.

[Brief description of drawings]

FIG. 1 is a rear view of an anti-fog mirror according to an embodiment of the present invention.

FIG. 2 is a right side view of the anti-fog mirror.

FIG. 3 is a schematic front view showing the heater of the anti-fog mirror in a partial cross section.

FIG. 4 is a cross-sectional view showing an internal configuration of the heater.

FIG. 5 is a front view showing a state in which a symbol (stegosaurus) is clearly displayed on the anti-fog mirror.

[Explanation of symbols]

 1 mirror 1a display part 2 heat transfer plate 4 heater 5 heating element 9 lead wire 10 insulating case (electrically insulating coating material) 12 junction member 14 fixture

Claims (1)

[Claims] 1. An anti-fog mirror capable of displaying a predetermined pattern on a mirror clouded by water droplets against the background of cloudiness, comprising a heat transfer plate having a planar shape substantially equal to the shape of the pattern and a positive temperature coefficient thermistor. And a heater entirely covered with an electrically insulating coating material. The heat transfer plate is provided in close contact with the back surface of the mirror, and the heat transfer plate is provided on the back surface of the heat transfer plate. An anti-fog mirror equipped with a heater.