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Publication numberUS3757509 A
Publication typeGrant
Publication dateSep 11, 1973
Filing dateMar 7, 1972
Priority dateMar 8, 1971
Also published asDE2210943A1, DE2210943B2, DE2210943C3
Publication numberUS 3757509 A, US 3757509A, US-A-3757509, US3757509 A, US3757509A
InventorsK Fujita
Original AssigneeSuwa Seikosha Kk
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Chronograph timepiece using digital display
US 3757509 A
A chronograph timepiece using digital display in an electronic chronograph watch in which digital display is effected by a liquid or solid state display device, wherein the time of day is measured by a watch mechanism and a time period is measured by a chronograph mechanism and these are memorized in a resistor device. The memorized time and time period are selectively displayed in the display device.
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Description  (OCR text may contain errors)

United States Patent Fujita 1 Sept. 11, 1973 CHRONOGRAPH TIMEPIECE USING 3,664,116 5/1972 Emerson et al 58/38 x DIGITAL DHSPLAY 3,686,880 8/1972 Samejima 58/23 R X 3,646,751 3/1972 Purland et al i. 58/152 R [75] Inventor: Kinji Fujita, Suwa-gun, Nagano-ken,

Japan Prima y '1 1tq:9 sli -..M! i 1 Asslgneei Kabushlkl Kalsha Suwa Serkosha, Attorney-Eric H. Waters,.l0hn G. Schwartz et a1.

Tokyo, Japan [22] Filed: Mar. 7, 1972 [57] ABSTRACT [2]] Appl. No.: 232,468

e A chrono ra h time iece usin di ital dis la in an F g P P g g P y [30] M g Apphcatlon Pmmty Data electronic chronograph watch in which digital display (If. ,1 Japan is effected a or solid state device wherein the time of day is measured by a watch mecha- [52] US. Cl. 58/23 R, 58/39.5 nism and a time period is measured by a chronograph [51] Int. Cl. G04c 3/00, G04f 3/06 mechanism and these are memorized in a resistor de- [58] Field of Search 58/23 R, 39.5, 74, vice. The memorized time and time period are selec- 58/l52; 340/3094, 309.5 tively displayed in the display device.

[ References Cited 2 Claims, 1 Drawing Figure UNITED STATES PATENTS 3,662,535 5/1972 Hedrick et al. 58/395 (WINTER mun r0? cow/rm (dun 72k coon/715R"?- 0 01 EX 5 4 3 2 0 fl Q l Coll/V725? COI/A/HE ram/75,2 COUNTER A F 4 F 4 H S, 4 4 a 2 z I 1 64/75 M \L VDD 5 C4 C3 C2 C1 CL 2 V FES/S/JZ-Mddflfi) C/(CU/T G 00 A/d? A 6475) 2 i c c, c, c, 5!

V e f VOLTAGE BRIEF SUMMARY OF THE INVENTION The invention relates to an electronic watch in which digital display is effected by a liquid crystal or light emitting diode and particularly to a display means for an electronic watch having a chronograph mechanism.

An object of the invention is to provide a watch of the above character having a simplified display panel.

Another object of the invention is to provide a display device having a plurality of digits utilized to indicate the time of day and a time interval. The time of day is a value which is displayed to indicate the present time on the watch, and the time interval refers to an elapsed period from a starting point to a finish point, a cycle time, a required time etc. The surface of a wrist watch is very small, and hence it is difficult to display all of the necessary information, i.e., month, date, hour, minute, second, tenths of seconds, and hundreths of seconds. For example, if four display windows are provided in a wrist watch, the month and date are displayed first, the hour and minute are displayed second, and lastly those of tenths and hundreths seconds are displayed. Thus, all of the data can be displayed by a unitary displaying device.

BRIEF DESCRIPTION OF THE DRAWING I play in accordance with the invention.

DETAILED DESCRIPTION Referring to the drawing, block 1 is a counter for producing a signal of 100 Hz. The timepiece comprises a quartz crystal oscillator which produces a time standard signal, said standard signal being divided to produce signal 0, of 100 Hz. Counters, 2, 3, 4 and constitute a watch mechanism. Counter 2 produces 0.01 sec, 0.1 sec and 1 sec 0 signals by two decimal counters, said 0.01 sec and 0.1 sec signals are coded in B (1, 2, 4, 8). Similarly, in counter 3, signal B of one second and seconds and one minute signal 0 are produced by both decimal counters and a divide-by-six counter. ln counter 4 signal 8;, of one minute and 10 minutes and one hour signal 0 are produced by decimal and divide-by-six counters. Counter 5 is a divide-by-24 counter for producing signal B of a time period. Counters 6, 7, 8 and 9 are a group of counters for constituting a chronograph mechanism, and have the same structures respectively as counters 2, 3, 4 and 5, and produce output signals A,.A .A .A, of coded signal (1, 2, 4, 8). Block 10 is a select gate for selecting either time signal (B,.B,.B .B,) or a time period signal (A,.A,. .A .A by closing or opening a switch S The output signal is designated as C C,, C or C Block 11 is a resistor circuit composed of flip-flop circuits in which 5 selected signals C,, Cg, C, and C are shifted in parallel by a clock pulse CL and are memorized. The shift pulse CL is produced by signal 0, of the counter 1 through NOR gate G. At this time, a starting switch S, for aetivating a memory operation is closed, the shift pulse is cut off and memorizing data is stored. Block 12 is a select gate block for selecting either C C (time period and minute) or C C (second and 0.1, 0.01 seconds) by closing or opening a select switch S Output signals D and D of selected coded signal (1, 4, 2, 3) are decoded into seven-segment type signals by decoder 13 and display panel 14 is energized.

Thus, according to the invention, the time measured by a watch mechanism having eight digits and a time period measured by a chronograph mechanism can be displayed by only four digits. Due to the operation of the memory circuit, a certain time can be displayed statically and exactly.

Moreover, although the circuit is complicated, it can be made into a watch size by incorporating the technique of integrated circuits. Particularly, if the circuit is comprised of complementary field effect-transistors (C-MOS), the consumption of electric power becomes very small.

What is claimed is:

1. An electronic chronograph timepiece comprising digital display means, a watch mechanism for producing signals representing time of day, a chronograph mechanism for producing signals representative of a time period, a first divider circuit for said watch mechanism, a second divider circuit for said chronograph mechanism, resistor memory means for momentarily memorizing signals produced by said first or second divider circuit, a gate circuit for controlling the feed of the signal of said first or second divider circuit to said resistor means, and switch means for operating said gate circuit, said digital display means including a digital display device for displaying the signal from said resistor means.

2. An electronic timepiece as claimed in claim 1 wherein the signals from said first and second counters are fed in parallel to said resistor means corresponding to the changes of said signals momentarily and selectively, and said signals are not fed to said resistor means only when the switch for operating said gate circuit is operated, whereas a signal fed to said resistor means at the moment of operating said switch is retained statically.

l 1' k i t

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3646751 *Dec 5, 1969Mar 7, 1972Detection SciencesDigital timing system
US3662535 *Jul 10, 1969May 16, 1972Lear Siegler IncAircraft time indicator
US3664116 *Apr 6, 1970May 23, 1972Gen ElectricDigital clock controlled by voltage level of clock reference signal
US3686880 *Sep 7, 1971Aug 29, 1972Samejima ToshihideElectronically controlled stop watch
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3884035 *Oct 15, 1973May 20, 1975Suisse Pour 1 Ind Horlogere MaChronograph watch
US3932723 *Apr 17, 1974Jan 13, 1976Tokyo Shibaura Electric Co., Ltd.Electronic range with automatic electronic digital timer
US3934400 *May 13, 1974Jan 27, 1976Kabushiki Kaisha Suwa SeikoshaElectronic timepiece
US3950935 *Sep 24, 1973Apr 20, 1976Kabushiki Kaisha Suwa SeikoshaChronograph wristwatch
US3992871 *Oct 9, 1973Nov 23, 1976Kabushiki Kaisha Suwa SeikoshaChronograph wristwatch
US4022014 *Apr 4, 1975May 10, 1977Timex CorporationCombination wristwatch/chronograph/wrist calculator/measuring device
US4022017 *Aug 14, 1975May 10, 1977Motomu AokiFull electronic car clock with digital display and method of time setting therefor
US4023345 *Nov 25, 1975May 17, 1977Kabushiki Kaisha Suwa SeikoshaElectronic timepiece
US4089156 *Apr 19, 1976May 16, 1978Casio Computer Co., Ltd.Stop watch device
US4287585 *Nov 22, 1976Sep 1, 1981Kabushiki Kaisha Suwa SeikoshaChronograph wristwatch
US4319350 *May 21, 1980Mar 9, 1982Ebauches Electroniques S.A.Electronic watch
DE2613414A1 *Mar 29, 1976Oct 21, 1976Timex CorpArmbanduhr
U.S. Classification368/70, 968/846, 968/957
International ClassificationG04G9/08, G04F10/04
Cooperative ClassificationG04F10/04, G04G9/087
European ClassificationG04G9/08D, G04F10/04