Stop watch

Claim 2

A stop watch, comprising, a reference signal generator circuit, a stop watch circuit for counting reference signals generated by said reference signal generator circuit and developing elapsed time data, an external operation switch circuit controlling the operation of said stop watch circuit, a display means, an elapsed time display timer circuit for controlling the stop watch circuit for giving said stop watch circuit commands to display a time measuring in said stop watch circuit continuously at said display means and to display an elapsed time at said display means for a selected time interval, an impact detecting circuit for detecting an impact force loaded on an outer case of the watch and for developing an impact pulse signal by converting the impact force to an electrical signal, wherein an elapsed time data in said stop watch circuit is displayed at the display means for a predetermined time interval by starting an operation of the elapsed time display timer circuit with an impact pulse signal generated from said impact detecting circuit when said impact detecting circuit detects a impact force caused by striking an outer case of the stop watch and is displayed fixedly at the display means as a final elapsed time by operating said external operation switch circuit while said elapsed time display timer is working.

Claim 3

A stop watch according to claim 1, wherein a stop watch circuit further comprises an elapsed time measuring circuit and a latch circuit.

Claim 4

A stop watch according to claim 2, wherein an elapsed time memory circuit and a display selecting circuit are provided for cooperating with said stop watch circuit.

Claim 5

A stop watch according to claim 2, wherein said elapsed time display timer circuit includes a latch timing signal generating circuit for generating a latch signal causing said latch circuit to read data measured in said elapsed time measuring circuit and for stopping the generation of said latch signal while said elapsed time display timer works.

Claim 6

A stop watch according to claim 1, 2, 3 or 4, wherein said external impact detecting circuit further comprises at least one piezoelectric element fixed to a portion of a case of the watch.

Claim 7

A stop watch according to claim 5, wherein said at least one piezoelectric element has a common electrode on one surface of a piezoelectric material and at least one corresponding electrode on the opposite surface thereof.

Claim 8

A stop watch according to claim 6, wherein at least two separated electrodes are provided on one surface of said piezoelectric material and a common electrode is provided on the opposite surface thereof.

Claim 9

A stop watch according to claim 7, wherein an electric signal generated on at least one electrode on at least one surface of said material of said piezoelectric element, is utilized as a controlling signal.

Claim 10

A stop watch according to claim 5 wherein a plurality of piezoelectric elements are provided.

Claim 11

A stop watch according to claim 7, wherein an electric signal generated at at least one electrode is utilized, as an impact detecting signal and at least one other electrode is used as an alarm generating element.

Claim 12

A stop watch according to claim 9, wherein an electric signal generated on at least one piezoelectric element is utilized as an impact detecting signal and at least one other piezoelectric element is used as an alarm generating element.

Claim 13

A stop watch according to claim 2, wherein said elapsed time measuring circuit is further provided with a plurality of memory circuits for memorizing only a final elapsed time measured when an impact force is loaded on a watch case, in said each memory, and for retrieving and displaying said data at said display means by an operation of said external operating switch circuit.

Claim 14

A stop watch according to claim 12, wherein said elapsed time measuring circuit is further provided with a data counter for counting a number of times said elapsed time is memorized.

Claim 15

A stop watch according to claim 1, 2, 3, 4 or 12 wherein a stop watch circuit starts to count a reference signal from an initial condition when a starting operation of said external operation switch circuit block is carried out.

Claim 16

A stop watch according to claim 12, wherein a reset signal for resetting said elapsed time measuring circuit is output from said memory circuit.

Claim 17

A stop watch, comprising, a reference signal generator circuit, a stop watch circuit for counting reference signals generated by said reference signal generator circuit and developing elapsed time data, an external operation switch circuit controlling the operation of said stop watch circuit, an elapsed time memory circuit for memorizing an elapsed time in said stop watch circuit, a display selection circuit for selecting either data from said elapsed time memory circuit or data from said stop watch circuit for display by a display means, an elapsed time display timer for controlling said display selection circuit and retaining a display of said elapsed time data for a predetermined time, an impact detecting circuit for detecting an impact force loaded on an outer case of said watch and for generating an impact pulse signal by converting the impact force to an electrical signal, wherein, said impact pulse generated by striking said case of said watch causes said elapsed time memory circuit to memorize elapsed time data in said stop watch circuit and simultaneously causes said elapsed time display timer to start operating to thereby cause said display selection circuit to convert a mode showing said data from said stop watch circuit into a mode showing data from said elapsed time memory circuit, further, an output pulse from said external operation switch circuit is applied to said display selection circuit when said converted mode is applied, causing said display selection circuit to control said display means so as to fixedly display said data memorized in said elapsed time memory circuit as a final measured elapsed time.

Claim 18

A stop watch, comprising, a reference signal generator circuit, a stop watch circuit for counting reference signals generated by said reference signal generator circuit and developing elapsed time data, an external operation switch circuit controlling the operation of said stop watch circuit, an elapsed time memory circuit for memorizing an elapsed time in said stop watch circuit, a display selection circuit for selecting either data from said elapsed time memory circuit or data from said stop watch circuit for display by a display means, an elapsed time display timer for controlling said display selection circuit and retaining a display of said elapsed time data for a predetermined time, an impact detecting circuit for detecting an impact force loaded on an outer case of said watch and for generating an impact pulse signal by converting the impact force to an electrical signal, wherein, said impact pulse generated by striking said case of said watch causes said elapsed time memory circuit to memorize elapsed time data in said stop watch circuit and simultaneously causes said elapsed time display timer to start operating to thereby cause said display selection circuit to convert a mode showing said data from said stop watch circuit into a mode showing data from said elapsed time memory circuit, further, an output pulse from said external operation switch circuit is applied to said display selection circuit when said converted mode is applied, causing said display selection circuit to control said display means so as to fixedly display said data memorized in said elapsed time memory circuit as a final measured elapsed time.

Claim 19

A stop watch comprising, a reference signal generator circuit, an elapsed time measuring circuit for counting reference signals generated by said reference signal generator circuit and for measuring an elapsed time, an external operation switch circuit for controlling the operation of said elapsed time measuring circuit, an impact detecting circuit for detecting an impact force loaded on an outer case of said watch and for controlling the operation of said elapsed time measuring circuit with a detected signal as an output thereof, a display timer circuit for displaying selected elapsed time data from those time data measured by an output signal of said impact detecting circuit and measured by an output signal of said external operation switch circuit, at said display means for a predetermined time interval, a plurality of memory circuits for memorizing an elapsed time data therein every time said measurement is carried out, a data counter for counting a number of times said measurement is carried out, wherein, said elapsed time data is fixedly displayed at said display means by making said display timer circuit operational in synchronization with an output signal of said impact detecting circuit, and further, while said display timer circuit is operating, memorizing only said elapsed time data recognized as a final data, in the plurality of memory circuits by a stopping operation on said external operation switch circuit and incrementing data in said data counter by one every time said elapsed time data is input to said memory circuit.

Claim 20

A stop watch comprising, a reference signal generator circuit, an elapsed time measuring circuit for counting reference signals generated by said reference signal generator circuit and for measuring an elapsed time, an external operation switch circuit for controlling the operation of said elapsed time measuring circuit, an impact detecting circuit for detecting an impact force loaded on an outer case of said watch and for controlling the operation of said elapsed time measuring circuit with a detected signal as an output thereof, a display timer circuit for displaying selected elapsed time data from those time data measured by an output signal of said impact detecting circuit and measured by an output signal of said external operation switch circuit, at said display means for a predetermined time interval, a plurality of memory circuits for memorizing an elapsed time data therein every time said measurement is carried out, a data counter for counting a number of times said measurement is carried out, wherein, said elapsed time data is fixedly displayed at said display means by making said display timer circuit operational in synchronization with an output signal of said impact detecting circuit, and further, while said display timer circuit is operating, memorizing only said elapsed time data recognized as a final data, in the plurality of memory circuits by a stopping operation on said external operation switch circuit and incrementing data in said data counter by one every time said elapsed time data is input to said memory circuit.