JPH07174866A - Luminous display device - Google Patents

Abstract

PURPOSE:To maintain the luminous intensity at a dark place of a luminous paint coated on a dial or needles at the necessary and sufficient intensity with the passage of time. CONSTITUTION:Needles 6, 7 are rotatably supported on a needle shaft 5a protruded on the front face of a dial 3. Time scales 3a applied with a luminous paint and serving as a luminescence section are formed on the front face of the dial 3. Luminous paints 6a, 7a are partially applied on the front faces of the needles 6, 7. Black light 8 radiating ultraviolet rays to the luminous paints is provided on the back side of the edge section 1a of a frame body 1. The light of the black light 8 can be efficiently radiated to the luminescence section by a reflector. A brightness sensor, an on-the-hour switch, and a timer circuit are incorporated in the circuit of the black light 8, and light energy is fed to the luminous paint, and the black light 8 starts the radiation of ultraviolet rays to feed the light energy to the luminous paint on the hour. After the period elapses when the light energy is sufficiently accumulated, a timer circuit is operated, and the black light 8 is turned off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a luminous display device which can be visually recognized even in a dark place by applying a luminous paint to a part of a dial such as an alarm clock or a pointer.

[0002]

2. Description of the Related Art As means for making a display visible even in a dark place, a means provided with an illumination means inside and outside a pointer or dial is adopted. However, such a lighting means requires a power source and a power feeding means for supplying power from the power source, which complicates the configuration and causes a high cost.

On the other hand, the luminous display device, in which the luminous paint is applied to a part of the dial or pointer, is advantageous in terms of cost because it does not require a power source for light emission or a power feeding means. It has been used in many instruments since ancient times.

[0004]

However, in the known luminous display device, the luminous paint used therein emits light by radiating the stored light energy upon receiving irradiation of natural light or illumination light. The emission brightness gradually decreases with the emission of light energy. For this reason, when several hours have passed since the surroundings of the display device became dark, there was a problem that the emission brightness was lowered to the extent that it hinders visual recognition of the display.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to constantly supply light energy to the phosphorescent paint so that the display is always visible in a dark place even though it is a phosphorescent display device.

[0006]

In order to achieve the above object, the luminous display device according to the present invention periodically supplies light energy to the luminous paint in the frame housing the dial and the pointer. A light source is provided.

The light source is preferably composed of a black light which radiates ultraviolet rays.

It is desirable that the light source control circuit includes a start switch that turns on the light source at predetermined time intervals, and a timer circuit that turns off the light source after a predetermined time has elapsed after turning on the light source.

[0009]

The light source provided in the frame periodically emits light to replenish the luminous paint with light energy on a regular basis. Therefore, the phosphorescent paint always emits light in a sufficiently excited state.

If a black light that radiates ultraviolet rays is adopted as the light source, the observer will not be made aware of the replenishment of light energy.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the luminous display device of the present invention is applied to an alarm clock will be described below with reference to the drawings.
As shown in FIGS. 1 and 2, a dial plate 3 is attached to the front surface of a mechanical body mounting plate 2 provided in the frame body 1 via the mechanical body mounting plate 2.
A front cover 4 made of a transparent plate is provided on the front surface of the frame body 1. A timepiece mechanical body 5 is attached to the central portion of the back surface of the mechanical body mounting plate 2, and a pointer shaft 5a protruding from the central portion thereof is a through hole provided in the mechanical body mounting plate 2 and the dial plate 3. And penetrates to the front surface of the dial plate 3.

An hour hand 6 and a minute hand 7 are rotatably attached to the pointer shaft 5a. On the front surfaces of the hour hand 6 and the minute hand 7, phosphorescent paints 6a, 7a are provided near the tip end over a predetermined length.
Is provided. Further, the phosphorescent paints 3a ... Are provided also on the time display letters 3, 6, 9, 12 and the time scale provided on the front surface of the dial plate 3.

On the front surface of the frame body 1, an edge portion 1a is made large to some extent, and on the back side of the edge portion, phosphorescent paints 3a, 6a, 7a.
A light source 8 is provided for periodically replenishing light energy. As the light source 8, a black light that radiates ultraviolet rays, which are non-visible rays, is adopted so that the observer is not aware of the light irradiation. As a means for controlling the light source 8, a control system, which will be described later, is provided so that the light source 8 can be turned on when the surroundings become darker than a predetermined darkness, and ultraviolet rays are regularly irradiated for a predetermined time.

A reflector 9 is provided on the back side of the frame 1 around the light source 8. The reflection plate 9 is formed in a shape such that the light emitted from the light source 8 can be efficiently applied to the display section.

A light-dark sensor 10 is provided below the hour display character indicating 6 o'clock formed on the dial plate 3. A CdS sensor is used as the light / dark sensor 10, and the control circuit 12 can be activated when the darkness becomes a certain darkness where it is difficult to visually recognize the time.

FIG. 3 shows a control system of the light source 8. This control system includes a brightness sensor 10, an hour switch 11 as an example of a start switch, a control circuit 12, and a timer circuit 13. The hour switch 11 is turned on at the hour via an hour detection mechanism (not shown). The timer circuit 13 turns off the light source 8 after a predetermined time has elapsed since the hour switch 11 was activated and the light source 8 was turned on.

When the surroundings are bright, the control circuit 12 is not operated by the light / dark sensor 10, so there is no difference from an ordinary timepiece. When the surroundings become dark, the light / dark sensor 10 operates and the control circuit 12 is kept operable. When the surroundings became dark, the phosphorescent paint 3a,
6a and 7a emit light with sufficient brightness, but the brightness gradually decreases with the passage of time. However, when the hour is reached after a certain time, the hour switch 11 operates, the control circuit 12 operates, the light source 8 is turned on, and ultraviolet rays are emitted.

When the time set in the timer circuit 13 has elapsed, the light source 8 is turned off. Each of the phosphorescent paints 3a, 6a, 7a irradiated with ultraviolet rays from the light source 8 is restored to its necessary emission brightness. After that, the brightness recovery operation of the phosphorescent paints 3a, 6a, 7a by the light irradiation by the light source 8 is repeated in the same manner as above until the surrounding becomes a bright state at every hour of every hour.

In the above embodiment, the hour switch detection mechanism, which is a mechanical switch mechanism, is used as the start switch 11, but it can be replaced with an all-electronic circuit. In addition, the repetition interval of turning on the light source 8 is
In the above embodiment, one hour is set, but every two hours or three hours.
It is also possible to change it appropriately, such as every hour.
The lighting time of the light source 8 per one time is determined by the relationship between the excitation energy generated by the light source 8 and the lighting repetition interval.

Further, although the above embodiment is an example applied to a timepiece, it goes without saying that it can be applied to various instruments other than the timepiece.

[0021]

As described above, according to the present invention, the luminous paint is regularly supplied with energy from the light source. Therefore, the luminous paint applied to a part of the dial and a part of the pointer is always necessary. It emits light with sufficient brightness and does not interfere with the visibility of the display in a dark place even though it is a phosphorescent display device.

If a black light is used as the light source, the observer does not need to be aware of the light irradiation, so that the commercial value is improved.

Furthermore, by providing an hour switch and a timer circuit in the control circuit of the light source, it is possible to suppress the replenishment amount of the light energy to the phosphorescent paint per one time to the minimum necessary, so that the power consumption is reduced. Can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of an embodiment of the present invention.

FIG. 2 is a front view of the same.

FIG. 3 is a circuit block diagram of the same.

[Explanation of symbols]

 1 Frame 3 Dial 6, 7 Pointer 3a, 6a, 7a Luminescent paint 8 Light source (black light) 11 Start switch (hour switch) 13 Timer circuit

Claims (3)

[Claims] 1. A phosphorescent display device capable of being visually recognized in a dark place by applying a phosphorescent paint to at least one of the dial and the pointer, wherein the phosphorescent material is provided in a frame housing the dial and the pointer. A luminous display device, characterized in that a light source for periodically supplying light energy to the paint is provided. 2. The luminous display device according to claim 1, wherein the light source is constituted by a black light that radiates ultraviolet rays. 3. The control circuit of the light source according to claim 1, further comprising: a start switch for turning on the light source at predetermined time intervals, and a timer circuit for turning off the light source after a predetermined time has passed after turning on the light source. A luminous display device characterized by being provided.