JPS5934962B2 - indicating instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an indicating instrument comprising a dial having a black coating layer for reducing light reflection, a measured value indicating member such as a pointer, and a light source for illuminating the dial.

Known indicating instruments of this type are generally coated with a black matte rack on the side of the dial facing the observer, on which white text is written.

Such dials ensure good readability of the respective readings with almost no reflections even when the dial is illuminated, which is generally done indirectly by an incandescent light bulb placed behind the dial. is guaranteed. Therefore, indicating instruments using such dials are particularly suitable for automobile instruments. However, this indicator also has significant drawbacks. That is,
The matte rack coating is extremely susceptible to scratches from any contact and special measures are therefore required to protect the coating layer during assembly of the indicator. Attempts to avoid this problem by covering the dial with a black velvet layer did make the dial less susceptible to scratches, but the cost was many times higher than that of a dial with a matte rack coating. I am not satisfied with the fact that it is. In addition, inscribing the required text on the velvet layer of the dial introduces new technical problems. It is an object of the present invention to eliminate such difficulties or disadvantages, and in particular to make the coating layer for reducing the light reflection of the dial as scratch-resistant as possible and easy and inexpensive to process. The object is to enable desired characters and symbols to be written on the coated surface without difficulty.

In this case, when the dial is illuminated, it is necessary to make the letters as three-dimensional and clearly recognizable as possible and stand out against the black surface without causing glare. The present invention has achieved these objects as follows.
That is, the coating layer of the dial was formed from a curable emulsion consisting of a synthetic resin rack and a large number of regularly or irregularly shaped plastic particles. Such a coating layer, which is formed from a black-colored synthetic resin rack and a large number of black-colored plastic fine particles with a diameter in the micron range, exhibits great abrasion resistance when the synthetic resin rack is selected accordingly and can be easily sprayed, for example. It is possible to write white or other colored letters or symbols without difficulty, for example by stencil printing.

The reflectance of such a coating layer is extremely small, on the order of a few percent. As a result, especially when the dial is illuminated, the text appears to stand out three-dimensionally against the black surface. The anti-glare effect and the three-dimensional effect can be enhanced as follows.

That is, a light source is placed between the dial and the viewer to shield it from the viewer, and the light source positioned in this manner illuminates the dial. For similar reasons, it is advantageous to arrange a color filter between the light source and the dial covering layer. It is particularly effective if the color filter is a blue filter that is matte on both sides. The invention will now be explained with reference to the embodiment shown in the drawings: the viewing end of the cylindrical casing 1 of the indicating instrument is closed with a transparent plate 3 held by a front ring 2. FIG.

Although not shown, a measuring device is disposed inside the casing 1, and a dial 4 is mounted on this measuring device. A pointer 6 attached to a pointer shaft 5 of the measuring device moves in front of this dial 4. The dial 4 has on its viewing side a thin coating layer 7 made of a curable emulsion consisting of a synthetic resin rack and a large number of spherical plastic particles. Furthermore, plastic particles are I
It is commercially available under the trademark Nextel 3101 (Nextel 3101). The dial 4 is illuminated by a single light source 8 placed between the viewer and the dial 4. This light source 8 consists of one light-conducting member 9 and one incandescent light bulb, which cannot be seen in the figure but is arranged at the rear of the casing 1, and is shielded from the viewer by the front ring 2. ing. In front of the light source 8, a color filter 10 made of a polycarbonate film colored blue and matted on both sides is arranged.

[Brief explanation of the drawing]

The drawing is a schematic longitudinal sectional view of an indicating instrument according to the invention. 1...Casing, 2...Front ring, 3...See-through plate, 4...Dial,
5... Pointer shaft, 6... Pointer, 7...
... Covering layer, 8 ... Light source, 9 ... Photoconductive member, 10 ... Color filter.

Claims (1)

[Claims] 1. In an indicating instrument comprising a dial having a black coating layer that reduces reflection of light, a measured value indicating member such as a pointer, and a light source that illuminates the dial, the coating layer 7 is formed by a curable emulsion consisting of a synthetic resin rack and a large number of plastic microparticles of regular or irregular shape and particle size in the micron range,
Indicating instrument. 2. The coating layer 7 is illuminated by one light source 8, and the light source 8 is arranged between the dial 4 and the viewer and is shielded from the viewer. indicating instrument. 3. Indicator according to claim 1, in which a color filter 10 is arranged between the light source 8 and the covering layer 7. 4. The indicator according to claim 1, wherein the color filter 10 is a blue filter with matte surfaces on both sides.