US3854277A - Electronic stop-watch and timepiece - Google Patents

Electronic stop-watch and timepiece Download PDF

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Publication number
US3854277A
US3854277A US00247618A US24761872A US3854277A US 3854277 A US3854277 A US 3854277A US 00247618 A US00247618 A US 00247618A US 24761872 A US24761872 A US 24761872A US 3854277 A US3854277 A US 3854277A
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United States
Prior art keywords
time
counting
stop
time count
count
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Expired - Lifetime
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US00247618A
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English (en)
Inventor
T Samejima
Y Ooi
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Seikosha KK
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Seikosha KK
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    • G—PHYSICS
    • G04—HOROLOGY
    • G04G—ELECTRONIC TIME-PIECES
    • G04G5/00—Setting, i.e. correcting or changing, the time-indication
    • G04G5/02—Setting, i.e. correcting or changing, the time-indication by temporarily changing the number of pulses per unit time, e.g. quick-feed method
    • G—PHYSICS
    • G04—HOROLOGY
    • G04F—TIME-INTERVAL MEASURING
    • G04F10/00—Apparatus for measuring unknown time intervals by electric means
    • G04F10/04—Apparatus for measuring unknown time intervals by electric means by counting pulses or half-cycles of an AC
    • G—PHYSICS
    • G04—HOROLOGY
    • G04G—ELECTRONIC TIME-PIECES
    • G04G9/00—Visual time or date indication means
    • G04G9/08—Visual time or date indication means by building-up characters using a combination of indicating elements, e.g. by using multiplexing techniques
    • G04G9/10—Visual time or date indication means by building-up characters using a combination of indicating elements, e.g. by using multiplexing techniques by controlling light sources, e.g. electroluminescent diodes
    • G04G9/107—Visual time or date indication means by building-up characters using a combination of indicating elements, e.g. by using multiplexing techniques by controlling light sources, e.g. electroluminescent diodes provided with means for displaying at will a time indication or a date or a part thereof

Definitions

  • a reset unit resets 58/74, 152 R; 235/92 T; 307/225 R the frequency dividers and the counters but is ineffective on the content of the counting unit consisting of [56] References Cited the counters during a time count while the device UNITED STATES PATENTS functions as a stop-watch.
  • a time-adjust unit receives 3,585,375 6/1971 Kedrick 235/92 T l Signals counter?
  • This invention relates generally to electronic watch movements and more particularly to a time-keeping device or apparatus capable of functioning both as an electronic stop-watch and timepiece.
  • Time-keeping devices are constructed as either stop- SUMMARY OF THE INVENTION It is an object of the present invention to provide an electronic time-keeping device having components and circuitry common to both a stop-watch and a timepiece mode of operation.
  • Another object is to provide a time-keeping device in which a reset unit allows resetting when the device is used as a stop-watch and is ineffective during a time count in the event resetting-is inadvertently attempted during atime count.
  • Still another object is to provide a device having a time-adjust unit for making time adjustments when the device is being used as a timepiece.
  • the electronic time-keeping device has a signal generator constructed as a crystal oscillator generating a base freqeuncy which is divided in a plurality of stages and counted in counters effecting a time count.
  • the time count as to minutes is stored temporarily in storage circuits and is then displayed on a display unit activated by decoder drivers.
  • Counting of the hours is done .in a separate counter and the hours are displayed on a display unit.
  • the storage circuits and associated counters are used to effect time counts when the device functions as a stop-watch or as a timepiece.
  • the hours of a time count are displayed when the device is operating in a timepiece mode of keeping time.
  • Counting control means comprise time-adjust means having means for generating a time-adjust signal ap plied to the counters to effect a time count adjustment thereby to adjust a time indication when the device is operating as a timepiece.
  • Reset means are also pro vided in the counting control means to reset the counters and gate means therein render a reset signal ineffective in the event that resetting is attempted during a time count, for example when operating in a stopwatch mode.
  • FIGS. 1 and 2 are jointly a block diagram of a timekeeping device according to the invention.
  • FIGS. 3 and 4 are block diagrams of portions of other embodiments of a time-keeping device according to the invention.
  • the time-keeping device embodying the invention comprises a signal generator 1 which is a crystal oscillator that produces a base or standard frequency which is applied to a plurality of frequency dividers 2,3,4 constructed as flip-flop circuits connected in cascade, which divide the base frequency to the desired unit of time.
  • the divided frequency signals or pulses are applied to a group of counters 5-11.
  • the last counter 11. is an hour counter connected through a connection S to the other counters which count time for minutes, seconds and fractions thereof.
  • the device is a 12 hour time-keeping device in which the time unit is 1/100 sec. and as a stop-watch it can function as such for 60 minutes, i.e. it can count for 60 minutes for operation in a stop-watch mode.
  • the first counter 5 counts 1/100 unit of a second
  • the second counter 6 counts 1/.10 unit of a second
  • the third counter 7 counts 1 unit of a second
  • the fourth counter 8 counts 10 units of a second
  • the fifth counter 9 counts 1 unit of a minute
  • the sixth counter 10 counts 10 units of a minute
  • the seventh counter 11 counts 1 hour unit and 10 units of an hour.
  • the outputs of the counters are applied to latch or storage circuits 12-17 that temporarily store the time counts of corresponding counters 5-10.
  • the outputs of the first sixlatch circuits 5-10 are applied to respective decoder driver circuits 18-23 which change the codes of the output signals of the corresponding latch circuit and at the same time amplify the outputs.
  • a separate decoder driver 24 is connected to the seventh or hour counter 11 and comprises a decoder 25 used for decimal transformation.
  • Gate circuits 26,27 constructed as NAND gates are likewise connected to receive outputs of the hours counter and one of these has inverter 28 connected intermediate it and the hours counter l 1.
  • the time count whether the device is operating as a stop-watch or a time-keeping device must be displayed.
  • the minutes and seconds and fractions thereof are displayed on six display elements 29-34 connected to the decoder drivers 18-23 connected to the latch circuits which are connected to the counters which effect the counts of the minutes and seconds, etc.
  • the outputs a-k of. the decoder driver 24 connected to the hours counter 11 are displayed on 11 elements 35-45.
  • the minute and seconds display elements 29-34 are, for example, light emission diodes that display numeral patterns and and the hour display elements 35-45 are lamps, but, of course, light-emitting diodes may be used instead of the lamps.
  • a time count start-stop switch unit 46 is provided and comprises two NAND gates 47,48.
  • a grounded movable switch contact 49 is operable to contact either a fixed contact 49b connected to one NAND gate 48 or another stationary contact 490 connected to the other NAND gate 47.
  • a J-K flip-flop 50 is connected to the NAND gates and has a terminal O which connects the start-stop switch unit 46 to the frequency dividers at the first frequency divider 2 for applying signals thereto as later explained.
  • a latch control switch unit 51 has a latch control switch 52 comprising two NAND gates 53,54 and a grounded movable contact 52a connectable either to a fixed contact 52c electrically connected to one NAND gate 54 or another fixed contact 52b electrically conne'cted to the other NAND gate 53.
  • a J-K flip-flop 55 is connected to the NAND gates 53,54 and has a terminal' Q connected to the latch circuits through a control connection 1 as shown for applying control signals thereto as hereinafter described.
  • a time-adjust unit 56 has two parallel NAND gates 57,58 both connected to a third NAND gate 59 connected to an exclusive OR-gate 60 which is connected to the fifth counter 9 of the counting unit to apply a reset signal thereto, as later described, and receives an input from the fourth counter 8 as shown.
  • Two grounded parallel switches 61,62 have movable contacts 61a,62a connected to respective parallel NAND gates 57,58 operable to engage respective grounded fixed contacts 61b,62b.
  • the parallel NAND gates 57,58 are connected in parallel to the first, and second counters 5,6 to receive count signals therefrom as will be seen hereinafter.
  • a reset unit 63 makes provision for resetting the device during operation as a stop-watch and it is not effective during a time count.
  • the reset unit has a reset switch 64 connected to two NAND gates 65,66 connected to a third NAND gate 67 providing connection through it to the frequency dividers and the counters. The connections are to the second and third frequency dividers 3,4 and the counters at ajunction to a connection r between all of the counters.
  • An inverter 68 is connected to the gate 67 and at a junction to the output connection between the start-stop switch and the frequency dividers.
  • the reset switch 64 has a grounded movable contact operable to contact a fixed contact 64b connected to one of the NAND gates 66 and to contact another fixed contact 64c connected to another of the NAND gates65.
  • the movable contact 52a of the latch control switch 52 is connected to the fixed contact 52b, and the output of the output terminal Q of the reset unit flip-flop 55 is at the level H; therefore, the input gates of the latch circuits 12-17 are in opened states.
  • the time-adjust switches 61,62 are both in a closed condition and the output of the NAND gate 59 is in a state of level L.
  • the frequency dividers 2,3,4 and counters -11 are considered to have been already set.
  • the latch control switch is closed, that is, the movable contact 520 is changed over in such a way that the contact is at point 52b the contact point 52c the contact point 52b.
  • the output of the NAND gate 53 changes through levels H L H, and in the change from level H to L the flip-flop 55 is triggered, and the output of the output terminal Q is reversed from level H to L. Therefore, the input gates of the latch circuits 12-17 are all closed and thereby in the latch circuits 12-17 are stored l, 2, 4, 5, 7.
  • the outputs of the latch circuits 12-17 display statically l, 2, 4, 5, 7, that is, the time 7 min 54 sec 21 on the display elements 29-33 through the decoder drivers 18-22. In this way it is possible to read out a particular time during the lapse of time.
  • RESETllNG OF THE COUNTING UNIT Resetting of the counting unit is carried out as follows.
  • the output of the terminal Q of flip-flop 50 is reversed, to the level L and the gate of the first frequency divider 2 is closed.
  • the movable contact 64a of the reset switch 64 is changed over to the contact point 640, and the out- .put of NAND gate 65 is reversed from the level L to H to keep the input of the NAND gate 67 at the level H. Since the other input of the NAND gate 67 has been supplied the output level H of flip-flop 50 is reversed by the inverter 68, the output of the NAND gate 67 assumes the level L.
  • the frequency dividers 3,4 and the counters 5-11 are reset.
  • This resetting does not occur, however, when a counting action is being performed in the counting unit, namely, when the input gate of divider 2 is in an open state. More precisely, when the input gate of the divider 2 is in the open state, the output of the terminal Q of flip-flop 50 is at the level H. Accordingly, the level L is supplied to the input of the NAND gate 67 through the inverter 68. Therefore, whatever level is supplied to the other input of the NAND gate 67, the level thereof is kept at level H, so that resetting is not effected.
  • a counting operation then is performed by the counters 9, 10, 11 and at the point in time when the counter 11 counts 3, the switch 62 is closed, thereby the supply of a time signal 8 1/100 sec to the counter 9 is stopped.
  • an input of the NAND gate 58 is kept at the levelH, and a time signal of H10 sec is supplied to the counter through the NAND gates 58,59 and the exclusive OR-gate 60.
  • the time adjust switch 61 is closed. After that, at the point in time when the counter 9- counts up to 5, the input gate of divider 2 is closed by the action of the start-stop switch 49.
  • the counters 7, 8, 9, 10, 11 store 3 oclock 25 min which has been reached, the input gate of the frequency divider 2 is opened by actuating the start-stop switch 49 and the time is successively counted. The time is displayedthrough the latch circuits and the display unit.
  • the adjustment may be made in such a way that by resetting the divider stages and the counting unit with the reset switch unit so when the time count corresponds to noon, actuating the start-stop switch 49 at once to open the input gate of divider 2 starts the time count.
  • the hour display is indicated by the lamps 3545, for example, when it is 3oclock, the lamp 37 is lighted. But duringithe time from 0 to 1 o'clock no lighting occurs in order toreduceconsumption of electric power. If it is desired to display 0 oclock clearly this is possible by connecting a lamp in the display unit to the output) terminalfor 0 oclock of the display actuating unit and supplying electric power thereto as in the other display elements.
  • the time count of the stop-watch was taken as 60min maximum, but in astop-watch for longer periods that need the hour unit it may be arrangedby providing a latch circuit for the unit of an hour as shown in FIG. 3.
  • the output of the counter 11 is supplied to the dispslay actuating unit through a latch circuit 69.
  • the two kinds of signals of the time-adjust switch 56, the signals of l sec and l/ 10 see, are utilized in the embodiment described but the device need not be limited to these signals andany required time signals may be used.
  • time was illustrated as displayed on a twelve hour display, but it is possible to have a 24 hours display by using a 24 notation counter and others, for example, a digital display 72, as shown in FIG. 4, may be used instead of a time display with lamps, provided electric power consumption is notcritical.
  • An electronic time-keeping device usable as a stop-watch and as a timepiece comprising,.a signal generator for generating pulses having a base frequency, frequency-dividing means dividing the base frequency in time, time count start-stop means for controlling a time count, counting means for counting the output pulses of said frequency-dividing means and developing therefrom signals representative of a time count having predetermined units of time, latch means comprising storage circuits receptive of said signals representative of a time count, latch control means to control storage of said time count signals to cause said device to function as a stop-watch means, display means for displaying a time count when said device functions as a stop watch and as a timepiece and in whichsaid time count start-stop means develops a signal output maintaining said counting means in a counting state, and includes counting means for controlling the content of a time count of said counting means comprising reset means for generating a reset output signal applied to said counters and gate means receiving a signal from said counting start-stop means and said reset output signal from said reset means rendering the reset output signal
  • An electronic time-keeping device usable as a stop-watch and as a timepiece comprising: a signal .generator for generating pulses having a basefrequency, frequency-dividing means dividing the base frequency,
  • time count start-stop means for controlling a time.
  • counting means for counting the output pulses of said frequency-dividing means and developingtherefrom signals representative of a time count having predetermined units of time
  • latch means comprising storage circuits receptive of said signals representative of a time count
  • latch control means for selectively controlling said latch means to continuously store one time count signal corresponding to a desired stop time thereby defining a stop-watch mode of operation and to successively store each time count signal thereby defining a time-piece mode of operation
  • display means for displaying a time count when said device functions in said stop-watch and said timepiece modes of operation
  • said counting means has means enabling it to continuously count when said latch means continuously stores one time count signal during the stop-watch mode to permit a plurality of time counts to be displayed during one timing sequence in the stop-watch mode.
  • said time count start-stop means develops an output signal for maintaining said counting means in a counting state and wherein said device further comprises counting control means for controlling the content of a time count of said counting means comprising reset means for generating a reset output signal applied to said counters and gate means receiving a signal from said counting start-stop means and said reset output signal from said reset means rendering the reset output signal ineffective when said time count start-stop means develops said output signal thereof for maintaining said counting means in said counting state.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Electric Clocks (AREA)
  • Measurement Of Unknown Time Intervals (AREA)
  • Electromechanical Clocks (AREA)
US00247618A 1971-04-27 1972-04-26 Electronic stop-watch and timepiece Expired - Lifetime US3854277A (en)

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JP2785671 1971-04-27

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US (1) US3854277A (en, 2012)
CH (1) CH612569B (en, 2012)
DE (1) DE2220783A1 (en, 2012)
FR (1) FR2134574B1 (en, 2012)
GB (1) GB1391995A (en, 2012)

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3950935A (en) * 1972-09-22 1976-04-20 Kabushiki Kaisha Suwa Seikosha Chronograph wristwatch
US3967098A (en) * 1975-04-14 1976-06-29 Harnagel Gary L Navigation instrument
US3991555A (en) * 1974-09-13 1976-11-16 Hughes Aircraft Company Digital timing circuit for display sequencing in two-digit wristwatch
US4010603A (en) * 1975-04-30 1977-03-08 Ensign Electronics, Inc. Time marking chronometer
US4019313A (en) * 1975-10-17 1977-04-26 Motorola, Inc. Liquid crystal watch module
US4022017A (en) * 1972-10-25 1977-05-10 Motomu Aoki Full electronic car clock with digital display and method of time setting therefor
US4023345A (en) * 1974-11-25 1977-05-17 Kabushiki Kaisha Suwa Seikosha Electronic timepiece
US4025774A (en) * 1975-06-16 1977-05-24 American Hospital Supply Corporation Timing apparatus including electronic calculator circuits
US4048478A (en) * 1974-06-18 1977-09-13 Kabushiki Kaisha Daini Seikosha Marking apparatus with electronic counters
US4075826A (en) * 1975-05-19 1978-02-28 Hughes Aircraft Company Timing circuit for digital wristwatch
US4084402A (en) * 1975-05-22 1978-04-18 Hughes Aircraft Company Timing circuit for display sequencing in a digital wristwatch
US4089159A (en) * 1975-06-23 1978-05-16 Citizen Watch Company Limited Electronic timepiece
US4089156A (en) * 1975-04-22 1978-05-16 Casio Computer Co., Ltd. Stop watch device
US4095406A (en) * 1974-09-06 1978-06-20 Kabushiki Kaisha Daini Seikosha Second adjustment system in an electronic watch
US4110966A (en) * 1975-12-26 1978-09-05 Casio Computer Co., Ltd. Electronic timepiece with stop watch
US4123896A (en) * 1975-10-09 1978-11-07 Kabushiki Kaisha Daini Seikosha Digital electronic timepiece
US4172360A (en) * 1975-10-14 1979-10-30 Kabushiki Kaisha Daini Seikosha Digital alarm timepiece
US4174606A (en) * 1976-05-20 1979-11-20 Sharp Kabushiki Kaisha Electronic watch having stopwatch function
US4176517A (en) * 1974-09-30 1979-12-04 Citizen Watch Co. Ltd. Integrated circuit for timepiece
US4184320A (en) * 1975-05-30 1980-01-22 Casio Computer Co., Ltd. Electronic stop watches
US4185452A (en) * 1976-07-08 1980-01-29 Arihiko Ikeda Digital time display system
US4201041A (en) * 1977-08-05 1980-05-06 Jeco Company Limited Digital electronic timepiece having a time correcting means
US4224789A (en) * 1977-05-20 1980-09-30 Kabushiki Kaisha Daini Seikosha Electronic timepiece
US4259737A (en) * 1978-07-13 1981-03-31 Jean-Claude Berney Sa Electronic watch
US4287585A (en) * 1972-10-09 1981-09-01 Kabushiki Kaisha Suwa Seikosha Chronograph wristwatch

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
HU180536B (en) * 1978-12-19 1983-03-28 Tatabanyai Szenbanyak Reactio timer

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3585375A (en) * 1969-12-22 1971-06-15 Lear Siegler Inc Aircraft time information system
US3646752A (en) * 1970-09-28 1972-03-07 Conveyor Specialties Co Plastic encased metal ribbed flexible conveyor chain
US3664116A (en) * 1970-04-06 1972-05-23 Gen Electric Digital clock controlled by voltage level of clock reference signal
US3672155A (en) * 1970-05-06 1972-06-27 Hamilton Watch Co Solid state watch

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3585375A (en) * 1969-12-22 1971-06-15 Lear Siegler Inc Aircraft time information system
US3664116A (en) * 1970-04-06 1972-05-23 Gen Electric Digital clock controlled by voltage level of clock reference signal
US3672155A (en) * 1970-05-06 1972-06-27 Hamilton Watch Co Solid state watch
US3646752A (en) * 1970-09-28 1972-03-07 Conveyor Specialties Co Plastic encased metal ribbed flexible conveyor chain

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3950935A (en) * 1972-09-22 1976-04-20 Kabushiki Kaisha Suwa Seikosha Chronograph wristwatch
US4287585A (en) * 1972-10-09 1981-09-01 Kabushiki Kaisha Suwa Seikosha Chronograph wristwatch
US4022017A (en) * 1972-10-25 1977-05-10 Motomu Aoki Full electronic car clock with digital display and method of time setting therefor
US4048478A (en) * 1974-06-18 1977-09-13 Kabushiki Kaisha Daini Seikosha Marking apparatus with electronic counters
US4095406A (en) * 1974-09-06 1978-06-20 Kabushiki Kaisha Daini Seikosha Second adjustment system in an electronic watch
US3991555A (en) * 1974-09-13 1976-11-16 Hughes Aircraft Company Digital timing circuit for display sequencing in two-digit wristwatch
US4176517A (en) * 1974-09-30 1979-12-04 Citizen Watch Co. Ltd. Integrated circuit for timepiece
US4023345A (en) * 1974-11-25 1977-05-17 Kabushiki Kaisha Suwa Seikosha Electronic timepiece
US3967098A (en) * 1975-04-14 1976-06-29 Harnagel Gary L Navigation instrument
US4089156A (en) * 1975-04-22 1978-05-16 Casio Computer Co., Ltd. Stop watch device
US4010603A (en) * 1975-04-30 1977-03-08 Ensign Electronics, Inc. Time marking chronometer
US4075826A (en) * 1975-05-19 1978-02-28 Hughes Aircraft Company Timing circuit for digital wristwatch
US4084402A (en) * 1975-05-22 1978-04-18 Hughes Aircraft Company Timing circuit for display sequencing in a digital wristwatch
US4184320A (en) * 1975-05-30 1980-01-22 Casio Computer Co., Ltd. Electronic stop watches
US4025774A (en) * 1975-06-16 1977-05-24 American Hospital Supply Corporation Timing apparatus including electronic calculator circuits
US4089159A (en) * 1975-06-23 1978-05-16 Citizen Watch Company Limited Electronic timepiece
US4123896A (en) * 1975-10-09 1978-11-07 Kabushiki Kaisha Daini Seikosha Digital electronic timepiece
US4172360A (en) * 1975-10-14 1979-10-30 Kabushiki Kaisha Daini Seikosha Digital alarm timepiece
US4019313A (en) * 1975-10-17 1977-04-26 Motorola, Inc. Liquid crystal watch module
US4110966A (en) * 1975-12-26 1978-09-05 Casio Computer Co., Ltd. Electronic timepiece with stop watch
US4174606A (en) * 1976-05-20 1979-11-20 Sharp Kabushiki Kaisha Electronic watch having stopwatch function
US4185452A (en) * 1976-07-08 1980-01-29 Arihiko Ikeda Digital time display system
US4224789A (en) * 1977-05-20 1980-09-30 Kabushiki Kaisha Daini Seikosha Electronic timepiece
US4201041A (en) * 1977-08-05 1980-05-06 Jeco Company Limited Digital electronic timepiece having a time correcting means
US4259737A (en) * 1978-07-13 1981-03-31 Jean-Claude Berney Sa Electronic watch

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Publication number Publication date
FR2134574B1 (en, 2012) 1976-08-06
DE2220783A1 (de) 1972-12-21
CH612569B (fr)
FR2134574A1 (en, 2012) 1972-12-08
GB1391995A (en) 1975-04-23
CH612569GA3 (en, 2012) 1979-08-15

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