US3791134A - Timepiece having a nuclear power source - Google Patents

Abstract

A timepiece comprising a nuclear power source in a capsule having a sensitive insulation of an output terminal, this insulation and output terminal respectively being protected by a protecting plate forming an intermediate back.

Description

United States Patent [191 Adler et al.

[ Feb. 12, 1974 TIMEPIECE HAVING A NUCLEAR POWER SOURCE [75] Inventors: Karl Adler, Grenchen; Georges Ducommun, Feldbrunnen, both of Switzerland [73] Assignee: Biviator S. A., Grenchen,

Switzerland [22] Filed: Feb. 8, 1971 [21] Appl. No.: 112,920

[30] Foreign Application Priority Data Feb. 23, 1970 Switzerland 2551/70 [52] US. Cl. 58/23 BA, 58/53, 58/90 [51] Int. CL... G04c 3/00, G04b 37/00, G04b 37/08 [58] Field of Search 29/77-79; 58/23 R,

58/23 BA, 23 C, 50 R, 23, 90; 224/4 R Primary ExaminerRichard B. Wilkinson Assistant Examiner-Edith Simmons Jackmon Attorney, Agent, or FirmDwight H. Smiley; Imirie & Smiley ABSTRACT A timepiece comprising a nuclear power source in a capsule having a sensitive insulation of an output terminal, this insulation and output terminal respectively being protected by a protecting plate forming an intermediate back.

5 Claims, 2 Drawing Figures //L I; Y F k I 1 I 1L J c 1 3 5 A r 4 s 21 23 TIMEPIECE HAVING A NUCLEAR POWER SOURCE BACKGROUND OF THE INVENTION Electric or electronically powered timepieces, such as watches, comprise a separate battery that is removably positioned within the watch case to enable replacement thereof when the battery power finally is dissipated. In the usual electric battery-operated watch the battery life is approximately one year, more or less, and must be replaced by an expert. During the normal life of a watch of this type the battery will have to be replaced a number of times and, on such occasions, the timepiece must be taken to a watch expert to effect such replacement. Regardless of the nature of the battery the case for the timepiece must be somewhat larger than desirable because the battery is a separate item.

It has been discovered that a radioactive or nuclear isotopic power source may be provided as a battery for providing the power for driving an electric watch, as disclosed in U.S. Pat. No. 3,562,613, but the nuclear power source must be included within a vacuum sealed case having a closure to enable the evacuation of the interior and a protecting plate protecting such closure from damage and the loss of vacuum with attendant possible excape of radiation and this enclosing structure is space consuming and, although such power source will normally last the life of the timepiece, as a separate battery it does not reduce the space requirements.

SUMMARY OF THE INVENTION According to the present invention, a nuclear isopic power source may be enclosed within a calotte surrounded by a wall and constituting a part of the casing for the timepiece. The power source is located within the calotte which is enclosed by a cover within the easing and sealed to the calotte wall, which cover has an aperture to enable evacuation of the chamber formed by the calotte and cover, which thereafter is sealed by a closure. A protecting plate is fixed to the calotte wall in spaced relation to the cover to mechanically protect the cover and closure. A drive shaft for the timepiece movement mechanism within the casing may extend through an opening in the protecting plate without danger of the excape of radiation.

BRIEF DESCRIPTION OF THE DRAWING FIGS. 1 and 2 are diametrical sectional views of two embodiments, respectively.

DETAILED DESCRIPTION OF THE INVENTION The watch of the first embodiment (FIG. 1) includes a case of which is shown a caseband l, in which is screwed a tubular piece 11 constituting a part of the back of the watch-case. This tubular piece 11 has an external flange 23 which compresses a Water resistant gasket 3. The glass of the watch-case and the movement of the watch are not represented.

The watch includes a nuclear isotopic power source of the type described, e.g. in US. Pat. No. 3,562,613. Such a power source constitutes a system for direct conversion of radioactive radiation power into electric power. The power source consists of a water resistant screened caspule which prevents any dangerous radioactive radiation to the outside.

The isotopic power source comprises an envelope formed by a calotte 4 and a cover 5, the latter being pressed or soldered in a water resistant manner on the calotte 4. In the cavity of the calotte 4 are fitted the active elements of the power source which are denoted by the reference numeral 6 and are not described in detail. Numeral 7 designates a glass or crystal bulb which permits making a vacuum inside of the source and which afterwards is hermetically sealed. The join between this bulb 7 and the cover 5 is also perfectly water resistant. A protection plate 8, disposed above the bulb 7 is fixed by any suitable means on a shoulder of the wall of the calotte 4. This protection plate 8 presents a hole 9 allowing e.g. to introduce a shaft of a gear of the watch. It protects also the bulb 7 mechanically and constitutes an intermediate back. A conductor 21 connects the active elements 6 of the power source with a piece of the watch movement; it is embedded in the bulb 7, goes out of the latter and passes through an isolated socket 22, driven into the protection plate 8. The bulb 7 with its conductor 21 constitutes an isolated outlet of the capsule containing the isotopic power source.

In a modified embodiment, the bulb 7 might be made from plastic material, but in any case it is very delicate piece which does not support any shock or high pressure. That is why it must be protected by the plate 8.

The calotte 4, constituting a part of the envelope of the power source, is fitted in the tubular piece 11 and constitutes a part of the back of the watch-case. The other part of the back of the watch-case is formed, as already said,by the tubulair piece 11 itself.

In the second embodiment (FIG. 2), the power source includes an envelope formed by a calotte l2 and a water resistant cover 13. The calotte 12 forms itself the back of the watch-case, on which the case-band 14 is snap-fitted. A protection plate 15, constituting an intermediate back and presenting a hole 16 is disposed above the bulb 7 and is fixed on a shoulder of the back 12. A pillar-plate 17 of the watch movement, presenting a hole 18 for the passage of the bulb 7, is fixed on a shoulder of the back 12 and carries pillars 19 which in turn support a bridge 20. The pillars 19 go through holes in the protection plate 15 and are anchored in the back 12.

What we claim is:

l. A timepiece comprising a casing for housing a timepiece mechanism, an evacuated capsule containing a nuclear isotopic power source enclosed in said casing and having a mechanically sensitive seal for the vacuum in the capsule, and a protection plate in said casing for protecting said seal from mechanical displacement, said plate constituting an intermediate back of said casing and separating said capsule from the timepiece mechanism.

2. A timepiece comprising a casing including a calotte surrounded by a wall, a cover within said casing and sealed to said calotte to define a chamber therebetween, said cover having an aperture to enable evacuation of said chamber, a closure sealing said aperture to maintain a vacuum in said chamber, a nuclear isotopic power source within said vacuum chamber, and a protecting plate fixed to said calotte wall in spaced relation to said cover and mechanically protecting said source and closure.

3. A timepiece according to claim 2, wherein the seal between said calotte and cover is water resistant.

4. A timepiece according to claim 3 said calotte constitutes a part of the back of the case of the timepiece.

5. A timepiece according to claim 3 wherein said calotte forms the back of the case of the timepiece.

UNITED STATES PATENT .OFEIICE CERTIFICATE OF CORRECTION Patent No. 3,791 13h Dated February 12, 197

Inventor) Karl Adler & Georges Ducommun It is certified that error appears in the aboveidentified patent hat said Letters Patent are hereby corrected as and t shown below:

In the Claims 2 M claim line 13 after "claim 3,", insert wherein Signed and sealed this 6th day of August 197 (SEAL) Attest: v

MCCOY M. GIBSON, JR. 0. MARSHALL DANNY Attesting Officer Commissioner of Patents ll PO-IOSO (IO-69) USCOMM-DC 6D376-P69 U.S. GOVERNMENT PRINTING OFFICE 1 l9! 0-366-334 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,791,13h Dated February 12, 197

Inventor) Karl Adler & Georges Ducommun It is Certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the Claims: M

Claim H a line 3 after "claim 3,", insert I wherein Signed and sealed this 6th day of August 197A.

(SEAL) Attest: v

MCCOY M. GIBSON, JR. 0. MARSHALL DANN Attes'ting Officer Commissioner of Patents USCOMM-DC 60376-5 69 u.s. GOVERNMENT PRINTING OFFICE I969 o-ass-su :M PO-IOSO (IO-69)

Claims (5)

1. A timepiece comprising a casing for housing a timepiece mechanism, an evacuated capsule containing a nuclear isotopic power source enclosed in said casing and having a mechanically sensitive seal for the vacuum in the capsule, and a protection plate in said casing for protecting said seal from mechanical displacement, said plate constituting an intermediate back of said casing and separating said capsule from the timepiece mechanism.

2. A timepiece comprising a casing including a calotte surrounded by a wall, a cover within said casing and sealed to said calotte to define a chamber therebetween, said cover having an aperture to enable evacuation of said chamber, a closure sealing said aperture to maintain a vacuum in said chamber, a nuclear isotopic power source within said vacuum chamber, and a protecting plate fixed to said calotte wall in spaced relation to said cover and mechanically protecting said source and closure.

3. A timepiece according to claim 2, wherein the seal between said calotte and cover is water resistant.

4. A timepiece according to claim 3 said calotte constitutes a part of the back of the case of the timepiece.

5. A timepiece according to claim 3 wherein said calotte forms the back of the case of the timepiece.

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