US 3609960 A
Description (OCR text may contain errors)
United States Patent Ofiice 3,609,960 Patented Oct. 5, 1971 U.S. Cl. 58-50 Claims ABSTRACT OF THE DISCLOSURE A timepece dial of translucent material has a light source such as an incandescent electric light in the material of the dia-1 which is illuminated to show the hour markers in relief. The dial preferably has internal refractng surfaces to rcfract light through the part bearing the hour markers.
The present invention relates to timepece dials Com posed of translucent material.
It has already been proposed to make a dial in a translucent material, for example certain types of glass, under which a source of light directly or indirectly lights up the dial, ditfusing the light so that the hour markers and the hands are opaque against a luminous ground.
It is also known -to use an elect'ic bulb in an optical conductor surrounding the dial, lighting of the lamp being achieved by an outside push-piece.
However, the fitting of an electric lamp or an optical conductor under or around a wrist-watch dial is virtually impossible without increasing the size.
The present invention has for its precise object a timepiece dial in a translucent material which obviates these drawbacks, characterized by the fact that it comprises a light source inserted in the dial material.
The accompanyng drawings show, by way of example, an embodinent of the invention.
The single figure shows a cross-section of the invention.
The single figure shows a dial body member 1 of translucent glass provided with blind bores or holes 7 made in the dial and designed to refract and direct difiused light from a light source towards the face of the dial. These holes locally ditluse the incident light llux particularly in the direction from which the dial is visible.
A cavity is provided in the dial and illuminating means in the form of lamp 20, which comprises a filament 3, is dsposed within the cavity. Electrical conductors 4, 5 are connected to the filament 3 and extend exteriorly of the dial body member and are connected to a battery (not shown) through a switch (not shown) which is positioned on the time piece casing.
The contrast efiect allows the viewer to clearly distinguish the hour markers 6 as luminous points of the surface of a darker dial and enables use of a weaker light source and, therefore, lower power Consumption, than would otherwise be required. The hour market-s 6 are optional and are preferably placed above holes 7, as shown.
Hour markers or timing indicia 6 can be either made in opaque material appearing dark against a lighted ground, or be made by providing an opaque coating on the dial 'and tracing the hour markers so that the light shines through and they are illuminated against a dark ground. In other words, the timing indicia are composed of a material having a dillerent light absorption property than the dial surface.
Lamp 20 can either be made independent of the dial, or in one piece with the dial as described in the previous example. i
It is possible to provide two or more light sources in a dial to provide uniform illumination thereof.
Instead of an incandescent light it is also possible to provide a fluorescent light.
What is claimed is:
1. In a timepece dial composed of translucent material having opposed surfaces and having means therein defining a cavity, a light source positioned in said cavity, and timing marks arranged on one of said surfaces of 'the dial, the improvement comprising means defining blind bores in said dial in the other o' said surfaces for reflecting light ron the light source towards said one surface of the 2. A dial according to claim 1, wherein said blind bores are arranged in alignment with said timing marks.
3. A timepece dial comprising: a body member composed of translucent material having opposed major surfaces and having therein between said opposed major surfaces means defining a cavity; timing indicia positioned on one of said major surfaces, said timing indicia having a different light absorption property than said one major surface; illuminating means dsposed within said cavity for illuminating said body member with light; and means defining a plurality of blind bores in said body member opening at the other of said major surfaces and positioned in superposed relationship relative to respective ones of said timing indicia for directing said light towards said one major surface; whereby said timing indicia are highlighted with respect to the remainder of said one major surface.
4. A timepece dial according to claim 3, wherein said timing indicia are composed of a material which is more' light absorptive than said one major surface.
5. A timepece dial according to claim 3; wherein said one major surface exclusive of those areas on which said timing indicia are positioned is composed of a material which is more light absorptive than said timing indicia.
References Cited UNITED STATES PATENTS l,8'88,366 11/1932 Willens 240--1 2,680,8l3 6/1954 Doyle 5^8-50 X 2, 745 ,946 5/ 1956 Protzmann 2.40-2.1 2,9'l6,*871 12/1959 Wegner 58-50 3,043,038 7/l962 Marble 58-50' X 3,2l4,577 10/1965 Protzmann 240-1 X 3,278,740 10/ 1966 Madansky 240--2.1 3,32'8,570 6/ 1967 Balchunas `%lo-2.1 3,349,235 10/ 1967 Kolodziej et al 240-2.1
F OREIGN PATENTS 1,003,314 11/1951 France 58-50 RICHARD B. WILKINSON, Primary Examiner S. A. WAL, Assistant Examiner U.S. Cl. X.R. 58- l27; 240-1