JPH0353284A - Transmission display type charging indicator - Google Patents

Abstract

PURPOSE:To brighten the liquid crystal display surface by utilizing the brightness of the outside for bringing about a back light state to a charging indicator, for an illumination light source of a liquid crystal display. CONSTITUTION:In a charging indicator 20 for displaying a state that a voltage is applied to an electric wire 11, a transmission type display is executed by utilizing an external light led into the charging indicator 20 as an illumination light source. That is, it goes into the charging indicator 20 through a transparent back case 23, scattered by a semi-transmission plate 7 and becomes a uniform light, passes through a transparent ground side current collecting plate 51 and a transparent substrate 50 and reaches the back of a semi-transmission type liquid crystal element 48. The semi-transmisstion type liquid crystal element 48 scatters this light and brightens brightly the liquid crystal display surface, and also, makes a non-transmission part of light which becomes a display pattern conspicuous. In such a way, the liquid crystal display contents of the charging indicator 20 attached to a high voltage overhead line 11 can be discriminated easily.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a power charging indicator that is mainly used by being attached to outdoor high-voltage electrical equipment or high-voltage overhead lines.

``Prior Art'' A power charging indicator is a warning device that displays the state in which a predetermined voltage is applied to electric wires or electrical equipment, that is, the power charging state, and is intended to prevent accidents caused by misunderstandings or careless mistakes.

FIG. 5 is a perspective view of a conventional general type power charging indicator 2 attached to a high-voltage electric wire 1, and FIG. 6 is a sectional view thereof. In the figure, 2l is a front case and 22 is a back case.

A transparent display window 3 is provided in the center of the front case 21, and a fixture 6 that also serves as a high voltage side current collector plate is fixed to the back case 22. A liquid crystal element 4 is located inside the display window 3 and is fixed to a substrate 5. The board 5 also serves as a ground side collector board and is also provided with a blinking drive circuit.

The power charging indicator 2 is used outdoors, mainly in substations of electric power companies and substation equipment in factories, by being attached diagonally downward to high-voltage power lines 1 at a height of 4 to 5 m or less above the ground, as shown in Figure 5. There are many things. When the rated voltage is applied to the high-voltage wire 1, the liquid crystal element 4 blinks in red to indicate ``charging'' or roNJ, and we can confirm the displayed content through the display window 3.

Here, a description will be given of the liquid crystal element used by the charging display as a display means. When a liquid crystal element receives external light on its glass surface, it is possible to arbitrarily create a part that transmits the external light and a part that blocks it by controlling the voltage, and the contrast of brightness can be adjusted by changing the contrast between characters and figures. This is a light-receiving display element that can be recognized as a liquid crystal display. Therefore, when the external light is strong and bright, the contrast between light and dark is large and the displayed content is clearly visible, and as the external light becomes weak and dark, it becomes difficult to see.

Depending on the relationship with the illumination light source, display methods for liquid crystal elements can be broadly divided into two types: a transmissive display method and a reflective display method. FIG. 7 shows the structure of the display system for the most commonly used TN type liquid crystal element. In the figure (a
) is a transmissive display type structure, with two panels placed before and after the liquid crystal cell 40.
In this method, two polarizing plates 41 and 42 are placed so that their polarization axes are orthogonal to each other, and the light is illuminated from behind by an illumination light source 44 through a semi-transmissive light scattering plate 43 for display. Since the LCD screen can be viewed brightly even in dark surroundings, it is used in automobiles, office automation equipment, LCD televisions, etc.

This method is generally called a backlight method. A backlight type liquid crystal element has a polarizing plate 41 in a liquid crystal cell 40.
oh. The transmissive liquid crystal element 47 is manufactured in the form of a transmissive liquid crystal element 47 in which a light-scattering plate 43 is attached to the transmissive liquid crystal element 47, or a transflective liquid crystal element 48 in which a transflective light scattering plate 43 is attached to the transmissive liquid crystal element 47.

If the LCD screen is bright enough due to the brightness of the surrounding light, the 7th
A reflective display system shown in Figure (b) is used. In the reflective display system, a reflective plate 45 with a light scattering plate is used in place of the transflective light scattering plate 43 and the illumination light source 44, and the liquid crystal cell 40
Ambient light that enters from the front side of the screen is reflected and displayed using the contrast of the reflected light. The reflective liquid crystal element 49 is a liquid crystal cell 40
, two polarizing plates 41 and 42, and a reflecting plate with a light scattering plate 45 bonded together, and are used in large quantities for small liquid crystal displays such as calculators and watches.

Conventionally, a reflective liquid crystal element 49 has been used exclusively as the liquid crystal element 4 of the charging display 2. Reflective liquid crystal element 49
As can be seen from other usage examples such as calculators and watches, the display is easy to see when receiving light from the front. As long as the power charging display 2 was installed and used in indoor electrical equipment, cubicles, or outdoor power substation equipment with a height of 4 to 5 meters or less above ground, the difficulty of viewing the display did not pose a major problem. . However, the reflective liquid crystal element 49 becomes very difficult to see in a backlit situation where the light from the front side is relatively weak and the light from the rear side is strong. In such a case, our pupils close and the surface of the reflective liquid crystal element 49 appears relatively dark.

In particular, when the power charging indicator 2 is used on a high-voltage overhead line, etc. located at a height of 10 m or more above the ground, the display surface of the power charging indicator 2 must be installed almost downward with the bright sky at the back. do not have. In such a case, the entire display window 3 appeared black, and it was almost impossible to identify the display contents of the liquid crystal element 4, such as "Charging" or rONJ.

``Problem to be Solved by the Invention'' A fundamental measure to improve the difficulty of viewing liquid crystal displays in backlit conditions is to make the liquid crystal display surface brighter. For example, a possible solution is to adopt the conventional bank light display method shown in FIG. 7(a). However, the power required for this illumination light source is thousands of times greater than the display energy of the liquid crystal element itself.

Originally, a power display is a device that detects the electric field when a predetermined voltage is applied to a wire or electrical device, and uses the energy of the electric field to display the power state on a liquid crystal element. Yes, and does not use batteries or other power sources.

Therefore, even if an attempt is made to adopt a conventional backlight system for a power-charging display, it is impossible to cover the power of the backlight light source only with the power of electric wires and electric fields around electrical equipment.

In order to make the power charging display a backlight type that is resistant to backlight, it is also possible to incorporate a T battery and a power lamp into the power charging display. In this case, it is expected that the power charging display will be quite heavy and large, and its structure will be complicated.

In addition, in order to make the LCD display appear bright in backlit conditions outdoors during the day, the power consumption of the light source lamp is considerably large, and the battery is also consumed rapidly, creating a new drawback in that it cannot be expected to have a long service life.

In this way, the question is how can we create a power display that can brighten the liquid crystal display surface like a bank light method while taking advantage of the feature of conventional power display devices that do not require batteries? was a major issue.

"Means for Solving the Problems" The key point of the present invention is to solve the above problems by focusing on external brightness, such as the brightness of the sky, which causes a backlighting condition on the charging display, and A transmissive display type power charging display is constructed by utilizing the light source as an illumination light source for a liquid crystal display.

That is, a transmissive liquid crystal element 47 shown in FIG. 7 is used as the liquid crystal element, and a semi-transmissive light scattering plate 43 is disposed on the back surface thereof. However, if the transflective liquid crystal element 48 is used, there is no particular need to provide the transflective light scattering plate 43. Then, external light is guided into the charging display, and the semi-transmissive light scattering plate 43 or the semi-transmissive liquid crystal element 48 is caused to perform a transmissive liquid crystal display.

Unlike the general backlight system, an illumination light source 44 or the like is not used.

The transflective light scattering plate 43 is not only commercially available, but also milky white glass,
Appropriate materials can be selected from milky white plastic, semi-transparent plastic, etc. The reflection, refraction, scattering, etc. effects of transparent or semitransparent materials can be appropriately utilized for the path for guiding external light into the charged display, or materials such as glass fibers can also be used.

``Function'' Next, the basic structure and function of the transparent display type electrification display device of the present invention will be explained using an example in which it is attached to an outdoor high-voltage overhead line. FIG. 1 is a perspective view showing the overall state, and FIG. 2 is a sectional view showing the relationship between each part. Note that these figures are examples for explanation and do not limit the structure.

In FIG. 1 and FIG. 2, 1l is a high-voltage overhead line, 20 is a transparent display type charging display of the present invention, and the following are its constituent parts. That is, 2l is a front case, 23 is a transparent back case, 3 is a display window, 48 is a transflective liquid crystal element, 50 is a transparent substrate, and 5l is a transparent ground-side current collector plate formed on the transparent substrate 50. , 52 is a blinking drive circuit, 6 is a fitting that also serves as a high-voltage side current collector plate, and 7 is a semi-transparent plate.

Compared with the conventional charging display 2 shown in FIGS. 5 and 6, the transparent display type charging display 20 has the following features. First, the material of the back case 22 is changed to a transparent material, and
A transparent back case 23 is used instead, with a shape designed to eliminate shadows created by the fixture 6 and the like against light from above. Next, a transflective liquid crystal element 48 was used in place of the conventional reflective liquid crystal element 49. The semi-transmissive plate 7 is provided to prevent the display pattern of the semi-transmissive liquid crystal element 48 from becoming difficult to see when the light entering the case is shaded.
It acts to scatter light. Further, the conventional substrate 5 using a copper-clad laminate was replaced with a transparent substrate 50 with a transparent ground-side current collector plate 5l.

Next, we will discuss its effect. Bright sky light from above enters the transparent display type charging display 20 through the transparent back case 23, as shown by the chain arrow in FIG. 2, and is scattered by the semi-transparent plate 7 to produce uniform light. The transflective liquid crystal element 48 passes through the transparent ground-side current collector plate 5l and the transparent substrate 50.
Reach the back of the. The semi-transmissive liquid crystal element 48 scatters this light, making the liquid crystal display surface bright and shining, and also highlights the non-transmissive portions of the display pattern.

By the above-described operation, we can easily identify the liquid crystal display contents of the transmission type power display 20 attached to the outdoor high-voltage overhead line II from a distance of several meters or more from the ground.

The liquid crystal display surface of the transmissive display type charging display 20 becomes brighter in proportion to the intensity of external light that causes a backlight condition. Therefore, whether you have your back against a clear blue sky or a cloudy sky, you can see the displayed content clearly. According to the results of the simulation experiment, when the transparent power charging display 20 is installed 10 meters above the ground, a red blinking roNJ display with font thickness of 3 mm can be displayed through a 25 mm x 6 4 mm display window in sunny or cloudy weather. It can be read clearly regardless.

The above is an example of the case where it is installed on an outdoor high voltage overhead line 11.
An example of the structure of the transmissive display type charging display 20 of the present invention and its effect of making the liquid crystal display surface appear bright even in backlit conditions have been explained. The transmissive display type charging display 20 can be used not only in such a case, but also under conditions where the back is dark and the front is bright, almost in the same way as the conventional charging display 2.

This is because, under such conditions, the semi-transmissive liquid crystal element 48 reflects half of the incident light from the display window 3 of the front case 21, and functions almost in the same way as the conventional reflective liquid crystal element 49.

"Example" Another embodiment of the invention is shown in FIGS. 3 and 4.

FIG. 3 is a perspective view showing the entire transparent display type charging display 20 for hanging electric wires, and is composed of three parts, namely, a current collecting plate part l2, a hanging tool I3, and a display part l4. Moreover, FIG. 4 is a sectional view showing the details of the display section I4.

The current collector plate portion 12 includes a high voltage side current collector plate 6l and a ground side current collector plate 52, which are provided around the high voltage overhead line 11 with an insulator 15 in between.

Further, the display section l4 has a front case 2l having a display window 3 in the center thereof, and a transmissive liquid crystal element 47 fixed in a semi-transparent back case 24 made of a semi-transparent opalescent material. It has a simple structure.

The semi-transparent back case 24 also serves as a light scattering plate for the transmissive liquid crystal element 47. This simple configuration was made possible by
This is because there is no longer a need to provide the ground-side current collector plate 52 inside the case, and there is no opaque part that blocks the incidence of external light like the holder 6 in the case of FIG.

A hanging device l3 made of the same material as the semi-transparent back case 24 not only holds the display section 14, but also has a blinking drive circuit therein (not shown), and also holds the current collecting plate section l2.
and a transmissive liquid crystal element 47 in the display section l4 are electrically connected.

``Effects of the Invention'' The present invention makes it possible to more clearly recognize the liquid crystal display contents of power display devices installed on high-voltage overhead lines and outdoor high-voltage electrical equipment, etc. It has become possible to perform maintenance and inspection work on electrical equipment more safely.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the transparent display type power charging display of the present invention attached to an electric wire, and Fig. 2 is a sectional view showing the relationship between each part. and explain the action. FIGS. 3 and 4 are views showing another embodiment of the present invention, FIG. 5 is a perspective view showing an example of the use of a conventional power charging display, FIG. 6 is a diagram of its dissection, and FIG. FIG. 2 is a diagram for explaining a display method of a liquid crystal element. In the figure, reference numeral 20 indicates a transmissive display type charging display 23 is a transparent back case 24 is a semi-transparent back case 47 is a transmissive liquid crystal element 48 is a transflective liquid crystal element 50 is a transparent substrate 5l is a transparent ground side current collector It is a board.

Claims (1)

[Claims] In a power display that uses a liquid crystal element as a display means to display the state of voltage applied to electric wires or electrical equipment, external light introduced into the power display is used as the irradiation light source as the display method of the liquid crystal element. What is claimed is: 1. A transparent display type power charging display device, characterized in that a transparent display type power charging display is made to perform a transparent type display.