Abstract: A sleep pattern timing apparatus for a user to record time before onset of sleep and to separately record sleep time to assist in the diagnosis and treatment of sleeping disorders can include a timer for recording awake time and sleep time of the user and preferably a plurality of switches such as a galvanic skin response switch and a tactile plunger-type switch electrically connected to the timer so that the timer records sleep time when at least one switch is released. Using an awake timer subsystem, the apparatus can also begin recording awake time when all switches are concurrently actuated and discontinues recording of awake time when at least one switch is released. A plurality of switches can reduce the opportunity for false actuation. The apparatus can be housed in a hand held housing to fall away when released to further reduce false actuation. The apparatus may be attached to the user with a wrist band for easy retrieval during sleep interruptions.

Abstract: An athletic training device includes a main control unit coupled to one or more finish line units via a communication link. The main control unit arranged to provide a pre-race start signal and a race start signal simulating an actual race event starting condition. The main control unit further arranged to time the race events, to determine reaction times and to measure weather and/or atmospheric conditions and to store all these as training statistics.

Abstract: An automatic, accurate and inexpensive timing bench, able to be purchased and used by any amateur. The bench consists of a conventional chronograph wristwatch (2) and a control box (1) provided with a housing (12) for the chronograph and a transparent cover (17). The box (1) further includes input ports, for receiving electric signals originating from timing cells, and electromagnets (51, 52) for automatically pressing the push buttons (8, 9) of the chronograph as a function of said input signals. As a result of auxiliary electric ports on each box, several of these boxes can be coupled in cascade to form a more complex timing bench.

Abstract: A golf play pacing device that is contained in the flag stick itself. The device includes an orientation sensing switch in the flag stick that is activated when the stick moves through an arc of approximately 45.degree., and reactivated when the stick is returned to perpendicular. The orientation switch controls circuitry that measures the time expired since the last reset of the device, and activates an alarm mechanism when that time is expired. The alarm mechanism includes visual alarms for the golfers and alarm capability for third parties. A sequence to monitor the putting time of players on the green can also be activated.

Abstract: An electronic watch with a chronograph function comprises a motor, a current time counter, a hand position counter, a coincidence detector and a backward/forward movement determining unit. When a chronograph mode is selected, a second hand moves backward or forward to a 12-o'clock (zero) position depending upon its position in a time measurement and indication mode. The electronic watch reliably resumes the time measurement and indication after it functions as a chronograph.

Abstract: The self contained flight duration measurement and recording apparatus is designed to be affixed to or contained within an object that will experience a duration of flight. The apparatus will measure and display the elapsed time of the object's flight. A timing device is positioned in a housing. The timing device is activated by acceleration forces on the object and deactivated by the deceleration forces acting upon the object. The force sensing unit that controls the time is an electrical switch that closes momentarily when subjected to inertial changes. The switch has a central core surrounded by a coil, both of which are integrated into a circuit. As the device experiences acceleration or deceleration, the core will contact the coil which will turn on or turn off the timer. Switch sensitivity can be adjusted as necessary for the specific purposes of the device.

Abstract: A Medical Timing System for assisting medical personnel in providing efficient and safe medical care to patients while decreasing the level of stress experienced by said medical personnel by means of allowing the medical personnel to monitor up to five different patient activities simultaneously. The device includes a housing structure, a power supply positioned within the housing structure, and a timing means electronically connected to the power supply and attached to the housing structure.

Abstract: An athletic jump duration timing apparatus is designed to measure the time from when an individual initiates a jump until he or she lands from the jump or stride. The apparatus will measure and display the elapsed time of the individual's flight or "hang time". A timing device is positioned in a housing. The timing device is activated by a sensor positioned under a weight bearing surface. A signal is sent to a controller which simultaneously activates two previously zeroed timers. These timers or counters begin counting the impulses from a clock generator. When the sensor senses a weight, the signal is given to the controller to cease the flow of impulses, which freezes the two counters. The event counter is cleared back to zero and the hold counter displays the hang time for the count value. Subsequent jumps are measured and the hold counter displays the jump with the longest hang time by comparing each jump against the event counter.

Abstract: A method to measure height of a vertical jump of a jumper. At least one switch is deactivated by the jumper stepping thereon. The switch is initially activated by the jumper jumping upward therefrom and thereafter deactivated upon return. A time period is measured while the switch is activated. The square of the activated time period is calculated and thereafter the result is multiplied by a constant to derive vertical jump height. Finally, the resultant vertical jump height of the jump is displayed.

Abstract: A chronograph mechanism comprises a coupling member (17) engaging, on the one hand, with a pinion (15") solid with the seconds wheel and, on the other hand, with the chronograph's seconds wheel (18). This coupling member (17) also carries a retractable finger (27) adapted to drive, each turn, the first rotatable member (35) of a cinematic transmission connecting together a rotatable member (38) of the minutes wheel to that of the hours counter (41). This transmission is indexed, between two drives by the retractable finger (27), by a jumper (51) engaged in an intermediate wheel (37) of this transmission. The coupling member (17) is controlled by two levers (44, 45), one lever (44) carrying a pin (44c) which, in the uncoupled position, locks the jumper (51) in the intermediate wheel (37)'s toothing. The minutes and hours counter rotatable members (38, 41), solid with zero setting cams (42, 43), are friction fitted on their respective axles.

Abstract: The control mechanism for displaying hours and minutes includes a tilting member (15) biasing against, under the effect of a return spring and via a pawl (18), a spirally shaped cam (12) located at the center of the movement, and which makes a full rotation in one hour. The tilting member (15) is lifted progressively by the action of the cam (12) to fall back instantly, once each hour. During this instantaneous falling back motion of the tilting member (15), a toothed sector (23) carried by the same drives, via a train of gears (24, 25, 26), a central pinion (27) carrying the minute hand. Thus, once at each hour, the minute hand is instantly reset to its initial position. The tilting member (15)carries a pawl (30) cooperating, at each of the instant falling back motions of the tilting member, with a star wheel with twelve branches, which rotates at the center of the movement and which carries a disk indicating hours, of which the display it thus of the so-called "incremental" type.

Abstract: A multi time interval pin comprising a cap rotatably attached to, and a pin rigidly attached to, a carrier base. The cap comprises a window wherethrough indicia on a carrier base upper surface is legible. The carrier base further comprises a carrier base lower surface with a carrier base projection extending perpendicularly from the carrier base lower surface. The pin also extends perpendicularly from the carrier base lower surface, such that the pin and the carrier base projection are approximately parallel. The pin, carrier base lower surface, and carrier base projection define an anti-rotation notch whereby the multi time interval pin may be prevented from rotating relative to a timer disc in which it is installed when the cap is rotated relative to the carrier base.

Abstract: A timepiece movement comprises a rotor driven for intermittent rotation by a stepping motor, a speed-reducing wheel train and a second stop device. The speed-reducing wheel train has a movement conversion mechanism for transmitting intermittent rotary movement of the rotor to continuous rotary movement of a second hand wheel in a smooth manner. The second stop device is moveable between a first position, for immediately stopping the second hand wheel, and a second position, for immediately moving the second hand wheel at a predetermined speed.

Abstract: A chronograph watch comprises time keeping first indicators (H, M, S1) used for displaying the time of day and chronograph second indicators (h, m, S2) used for displaying an interval of time in response to a control arrangement (P1, P2) with the aid of which the chronograph can be started, stopped and reset to zero. The chronograph watch includes instantaneous conversion means for at least one of the second indicators (here the seconds counter S2) into an indicator of another function, for example an indication of the date (Q), when the chronograph is not in use. In such example there is also provided the transformation of the minutes counter (m) into a four-year cycle indicator (BISS) and the hours counter (h) into a months indicator (Mo).

Abstract: An athletic shoe which includes a timing device for measuring the amount of time the athletic shoe is off the ground and in air. The athletic shoe can also include a notification device which can be operatively coupled to the timing device for notifying a wearer of the athletic shoe of a message. The message can include information related to the amount of time the athletic shoe is off the ground and in the air.

Abstract: In a stopwatch of this invention, when a lap switch is operated after time measurement is started, a lap time from the immediately preceding lap switch operation to the current lap switch operation is stored and compared with a measurement time after the current lap switch operation. Since an alarm tone is generated if the measurement time after the current lap switch operation coincides with the stored lap time, the immediately preceding lap time can be used as a target time of the time measurement. The stopwatch can be conveniently used when a running speed is increased or decreased in each lap in a track race or the like.

Abstract: A time measurement apparatus provides reliable estimation of a current LAP time by comparing it with a standard LAP time. A LAP time watching circuit compares the data in a LAP time measuring circuit with a data in a standard LAP time memory circuit, and outputs a LAP time coincidence signal to an output signal memory circuit. The output signal memory circuit drives an audible indicator.

Abstract: An analog electronic timepiece comprises a system control circuit for outputting a control signal to each operable circuit in response to a signal from an outer input switch, a chronograph storing circuit for storing the value a chronograph measuring means by a lap control signal outputted from the system control circuit, a lap time calculating circuit to which a measuring data of the chronograph measuring circuit and a former measuring data stored in the chronograph storing circuit by a former lap control signal are inputted for calculating the time difference between the above two data and outputting a correcting drive signal if the hand requires a correcting drive as a result of the above calculation and a drive judging circuit to which a lap input signal, an interruption signal, and a correcting drive signal outputted from the system control circuit are inputted for outputting a data of the drive number if the hand requires driving.

Abstract: A trigger signal generated by a start pistol is inputted to a timekeeping device. The trigger signal is synchronized with reference clock pulses and then transmitted to competitors as sound and light start signals. In addition, counting in a timekeeping counter is started at the timing of this signal.

Abstract: A timer which measures the duration of a first of two consecutive contractions and also measures the elapsed time period between the beginning of said first contraction and the beginning of a second of two consecutive contractions and which displays successive pairs of first and second contractions and which also compares the most recent time measurement values to a user programmed target time and further alerts the user when a measured time is less than said programmed target time.

Abstract: A display unit is arranged in cooperation with a twenty-four hour clock to effect registration and storage of timed events and permitting recall of the timed events, with the unit arranged for ease of mounting within an emergency vehicle and the like.

Abstract: A turnstile operated game for determining the elapsed time between a starting event and an ending event comprising a turnstile composed of a horizontal member supported above the ground, a vertical shaft rotatably mounted on the horizontal member, an arcuate cam mounted on the turnstile and being responsive to the rotation of the shaft, a microswitch mounted on the turnstile adjacent the cam, the microswitch having a toggle arm adapted to be contacted by the cam to actuate the microswitch upon a predetermined rotary movement of the shaft, a horizontal lever connected to the vertical shaft and having a first portion extending away from and beyond the horizontal member, the lever having a second portion extending on the opposite side of the shaft from the first portion thereof, a timer connected to the microswitch such that the timer is turned on when an object contacts and pivots the first portion of the lever, the contacting and pivoting of the first portion of the lever by the object constituting a starting

Abstract: A timing system for swimming race which records, displays, and prints the time of race. To provide a mask circuit in a control device which controls each signal, enables the timing system to exactly perceive a swimmer's touch. Furthermore, a top edge panel is provided on a touch panel so as to perceive a swimmer's touch at an oblique angle. A plurality of lane boxes are provided for backup of a touch signal and a starting block signal, in case of failure and misoperation of the control device. Further, a visual display device is provided in order that a swimmer can recognize a starting signal visually.

Abstract: An athletic shoe which includes a timing device for measuring the amount of time the athletic shoe is off the ground and in air. The athletic shoe can also include a notification device which can be operatively coupled to the timing device for notifying a wearer of the athletic shoe of a message. The message can include information related to the amount of time the athletic shoe is off the ground and in the air.

Abstract: A dual center wheel (38), provided with a plurality of dual center wheels (36) for display of times in different time zones, driven on a hands wheel for displaying the current time, and a dual adjustment member (49) adjusted by an external adjustment member (9), is formed from a gear (38a) and a pair of planetary wheels (44, 45) supported on the gear (38a). The dual center wheel (38) is also provided with a dual wheel (43), for which the rotation is regulated by means of a jumper spring, which engages one of the planetary wheels (44), and with a dual hour wheel (46) which engages the other planetary wheel (45) rotating on the same shaft as the dual wheel (43). The dual hour wheel ( 46 ), of which rotanional speed is reduced as a result of the rotation of the dual center wheel (38), makes one turn of an integer fraction of a rotation for a one pitch rotation of the dual wheel ( 43 ).

Abstract: A pacing device provides feedback to a user based on a preselected pace time for an activity. A linear array of colored lights includes two lights of a first color and one light of a second color and is operated in accordance with a predetermined lighting sequence. The predetermined lighting sequence makes: 1) a combination of the two lights of the first color visible to the user during a time less than or equal to the preselected pace time, 2) a combination of one of the two lights of the first color and the one light of the second color visible to the user during a first portion of a time greater than the preselected pace time, and 3) only the one light of the second color visible to the user during a second portion of the time greater than the preselected pace time.

Abstract: In a stopwatch of this invention, when a lap switch is operated after time measurement is started, a lap time from the immediately preceding lap switch operation to the current lap switch operation is stored and compared with a measurement time after the current lap switch operation. Since an alarm tone is generated if the measurement time after the current lap switch operation coincides with the stored lap time, the immediately preceding lap time can be used as a target time of the time measurement. The stopwatch can be conveniently used when a running speed is increased or decreased in each lap in a track race or the like.

Abstract: An apparatus that prepares food in cycles is achieved by tying in a timer which resets to zero and measures elapsed time from cycle to cycle.

Abstract: A pitch-mark repair tool used for repairing pitch-marks made on greens when playing golf is provided with a timing device which allows specific time periods applicable to a game of golf, such as the five-minute rule, to be measured objectively and simply with the specific advantage of being a non-disturbing yet readily usable piece of equipment which is required in general to be carried by all golfers. The repair tool timing device has operating buttons which are on the pitch-mark repair tool and which can be recessed and of such a size and shape that unintentional activation of the timing device is prevented when using the tool purely to repair a pitch-mark.

Abstract: A watch movement is a combination of a chronograph module and a motor module, the motor module comprising a third wheel, a first power take off composed of a toothed wheel fixed to the cannon-pinion and a second power take off composed of a pinion fixed to the seconds axle in the center, the chronograph module having a chronograph hand, a hand for the minute counter and a hand for the hour counter. This watch movement also has a third power take off composed of a wheel fixed to the third wheel, these three power take offs being accessible from the same side by the upper face of the motor module and the chronograph module being placed against said upper face of the motor module, and in that the hand of the chronograph, the hand of the minute counter and the hand of the hour counter are driven respectively and in independent manner by said second, third and first power take offs.

Abstract: An analog electric timepiece having a stop watch, and in the movement of hands when timepiece is used as the stop watch. The motion of the second hand, which moves to indicate one second at the time of the ordinary time display, is converted to the motion of a 1/10 second hand and moreover, the 1/10 second hand is allowed to move repeatedly only inside the range corresponding to the range from the zero-hour position to the 9-minute position of the dial of the timepiece. Furthermore, the minute hand and the hour hand for the ordinary time display are switched to operate as the second hand and to the minute hand, respectively, so as to accomplish an analog stop watch capable of measuring and displaying the 1/10 second.

Abstract: An apparatus which can determine the velocity of a projectile based on distance traveled and time of travel. The apparatus includes a manually operated stopwatch function which can measure elapsed time to at least hundredths of a second, a calculator function which can convert elapsed time and distance traveled by the projectile into velocity of the projectile, and a display to show the velocity. The apparatus can have either a digital or an analog stopwatch function.

Abstract: A stopwatch according to the present invention can measure a lap time by the operation of a lap switch of a key input portion and stores the measured lap time in a RAM. When the lap switch is operated, a minute hand is immediately moved to a position of 0 o'clock, and is started its rotation from the position of 0 o'clock. The hand is rotated at such speed that the hand arrives at a position of 10 o'clock after the preceding lap time stored in the RAM is elapsed. In order to rotate the hand at the above described speed, a microprocessor unit calculates the time interval to supply pulse signal to a step motor. Since the hand is moved from the position of 0 o'clock to the position of 10 o'clock at the above described speed, percentage of the lap time being measured at present with respect to the preceding lap time can be immediately known.

Abstract: An electronic timepiece with timer function comprising a stopwatch counting means operated from the signal from an input means, timer subtraction counting means for making subtraction from an arbitrary set value in the interlocking arrangement with said stopwatch counting means, an interrupt controller for outputting starting signal to said stopwatch counting means and said timer subtraction counting means, wait time counting means for counting the time from time-up to a lap time processing when the signal from said input means is the lap time processing of stopwatch time counting and the time of said subtraction timer is up before said lap time processing, and counting means for counting the time till time-up when said lap time processing is before said time-up.The timepeice can let the runner of the marathon and the like know easily the delay and advance from the set timer set by him.

Abstract: A device for monitoring the passage of a big game animal along a game trail has a battery powered, digital clock within a container with the container wall provided with a telephone type of jack which includes a pull pin holding switch contacts apart to maintain the clock in operation. A trip line is connected to the pull pin and exerts a direct pull thereon when engaged by a passing animal with the position of the pulled free pin indicating the direction in which the animal was travelling.

Abstract: An athletic performance measuring device is provided which can be conveniently worn on the user's finger is disclosed. The device can provide a variety of functions such as lap counting and timing. An actuator is provided in the form of a thumb switch, to allow the counter/timer to be held and operated by one hand, without disrupting the athlete's performance.

Abstract: The minute summer is used as a counting-down device and comprises a rotating disk sector (11) revealing a contrasted dial sector preceding the zero of the graduated scale, at the start of counting-down, and equipped with cut-out (15). This cut-out reveals a second sector (14) of contrasted appearance at the moment when the front edge (19) of the first sector reaches a graduation mark close to zero, for example the final minute, so as to inform the wearer that the final minute has started. Particularly intended for yachting.

Abstract: A multimode electronic timepiece has an electroptic display, an alarm, several pushbuttons and an integrated circuit programmed to keep time. Several timepiece operating modes include a pace mode, wherein audible periodic beeping sounds are produced by the alarm which correspond to the value of a preselected pace of an operator. A first manual actuation of a pushbutton commences a timing event, and second manual actuation of the pushbutton terminates the timing event. An internal program alters the preselected pace and stores an altered pace in response to the time elapsed between first and second actuation of the pushbutton. The program displays the altered pace and causes the alarm to beep at a rate equivalent to the altered pace.

Abstract: A compact and inexpensive meter for measuring and recording the time an engine driven apparatus has been running. The apparatus includes a signal generator such as a piezoelectric transducer which produces an electrical current when the engine driven apparatus is operating, a rectifier for converting the electrical current produced by said signal generator to direct current, a transistor for receiving the electrical current from the rectifier and switching on a stopwatch timing unit when the voltage received from the rectifier reaches a predetermined level.

Abstract: One embodiment of this invention has an electronic circuit which is configured to count the elapsed time in minutes since the initiation of a nursing session. The elapsed time is indicated on a visual display (23) which also includes a right/left breast subdisplay (23d) for indicating the breast from which the baby last fed, which is also the breast to be used when the baby starts feeding again. Breast feeding timer (10) includes a reference clock (11), a clock counter (14), an alarm counter (16), a three digit digital display (23), including a separate right/left subdisplay (23d), an audible alarm (26), and plurality of switches for controlling and initiating stop, start, reset, alarm program, and right/left selection display functions.

Abstract: A timepiece includes at least two motors (1, 2), in which the shafts (4, 16) of the rotors (3, 15) are arranged head-to-foot in a manner such that the free end of the pinion (27) fixed to the shaft of one rotor extends in the direction opposite to that in which extends the free end of the pinion (30) fixed to the shaft of the other rotor. Each of the pinions (27, 30) is in mesh with a toothed wheel (26, 29), such wheels being mounted coaxially with one another on either side of a base plate (40). Each of the wheels directly controls a hand (25, 28) indicating a unit of time.

Abstract: A running shoe with an integral timer includes a shoe having an upper body portion and a lower sole portion divided into a toe portion and a rearward heel portion separated by a recessed arch portion. An electronic digital stop watch is embedded in the material utilized to form the recessed arch portion and a flexible cover is removably secured to cover a display and function control buttons provided on side wall portions of the central arch. A step counter may be mounted in the arch and includes an actuating switch embedded in the sole portion of the shoe for counting steps of an individual. Start/stop and reset buttons for the stop watch may be provided on heel and toe portions of the shoe, enabling an individual to actuate the stop watch by kicking the heel or toe of the shoe against an object.

Abstract: A digital wristwatch having a case and strap also serves as a computer to display speed, distance, and pedaling cadence when temporarily attached to a holder on the bicycle handlebar. Wheel and sprocket sensors are connected to electrical terminals in the holder. The wristwatch is provided with external electrical terminals connected to a microcomputer in the watchcase which uses signals from the sensors when the watchcase is temporarily retained in the holder. The microcomputer is preprogrammed to provide an improved dual mode circuit which keeps time in a "watch mode" and which uses the sensor signals to make speed, distance, and cadence computations and display them in a "bike mode." The computations may be altered and new constants entered in a "calibration mode," through manual actuators. Changes of state within a mode are responsive to manually actuated push-buttons, to lapse of predetermined time periods or to condition of an annunciator.

Abstract: A combination ski pole handle with a hand-operated watch or timing device mounted therein is disclosed, including a molded hand grip for mounting on the top end of a ski pole, a watch protectively mounted within the hand grip thereof and disposed on a rearwardly sloping top portion thereof to be easily viewable by the skier with the ski pole disposed in near vertical fashion which includes a timing function, and a finger-actuated trigger mechanism for controlling the timing function of the watch.

Abstract: A device for measuring a person's quickness comprising a stopwatch, a measured length of cord, and a pair of tags. Each of the tags has a clip at one end for securing the tag to the clothing of a person whose quickness is to be measured. One tag is connected to one end of the cord by a Velcro type separable fastener, the other tag is connected by a Velcro type separable fastener to a pull strap which actuates the stopwatch to start and stop the stopwatch upon successive pulls of the pull strap. The other end of the cord is also connected to the pull strap. When the stopwatch is held at a starting position and the person being tested leaves the starting position, the tag connected to the pull strap actuates the stopwatch to turn it on and then separates from the pull strap. When the person has run a predetermined distance equal to the length of the cord, the cord pulls the pull strap to stop the stopwatch and then is separated from the tag attaching the cord to the person's clothing.

Abstract: The recording device is embodied as a stop watch 10 comprising a watch body 11 having a two-piece strap to secure the stop watch 10 to one hand 20 of its user. On one side, the watch body 11 has a display face 13 and an elongate button 16 for controlling the functioning of the watch 10 and the display on the display face 13. A central region 26 of the watch body 11 is flexible enabling the watch body 11 to be bent in a U or J shape around the hand 20 between forefinger 28 and thumb 27, the two pieces 21, 22 of the strap holding the watch body 11 securely on the hand 20 and wrist 24. With the watch body 11 in the latter described disposition on the hand 20, the button 16 can be actuated by the finger tips 31. Thus, the stop watch 10 can be easily operated one-handed making it particularly suitable for use by athletes.

Abstract: A timing device is provided for the differential timing of game play, such as chess, employing an easily readable display means and an accurate timing means. According to the preferred embodiment of the present invention, the display means further comprises two concentric articulating discs of different color, usually black and white. The display is connected to an electric motor driven by an accompanying electric circuit such that one disc is driven by the motor. The direction of travel of the motor is controlled by player actuated switches which are tripped upon completion of each move. Differential time is displayed by the eclipse of one disc by the other.

Abstract: In a stop watch, when a switch is depressed, hands are operated to start timing. Every time a split time switch is depressed, the time intervals between time points at which the split time switch is depressed are sequentially stored in a memory. Therefore, when the switch is re-depressed, the stop watch terminates its time measurement. A plurality of split times up to the end of time measurement can be reproduced, from the latest split time to the earliest split time.

Abstract: An electronic watch with a chronograph system has a second hand for displaying the normal time and chronograph time, minute and hour hands for the normal time, a chronograph minute hand and a chronograph hour hand. The watch has a first motor for driving the second hand, a second motor for driving the minute hand and hour hand, and a gear train for transmitting the output of the first motor to the second hand, chronograph minute hand, and chronograph hour hand. A resetting mechanism is provided for resetting the chronograph minute hand and chronograph hour hand to respective zero positions. A first circuit means operates the first motor to reset the second hand to the zero position, and a second circuit means operates for starting and stopping the first motor. The resetting mechanism, first and second circuit means are operated by external manipulating means, thereby changing a normal time display mode to a chronograph time display mode.

Abstract: Insulating material is used to attach a conducting foil patch to conductive urface of motor case. The patch is a part of an open electrical circuit, along with a power source, timer and connecting wires until impact which causes the patch to collapse and come in contact with the motor surface, thus closing the circuit. When the circuit is closed and voltage is present, the timer records the time of impact and continues to count. A piezo-electric pin attached to motor case and connected to the timer creates voltage pulse upon detonation of motor case and this pulse stops the timer. Thus, accurate measurements of time lapse between impact and detonation can be made.