Abstract: It is an object to make it possible to drive a motor at a high speed without causing any shift in the position of a hand. A memory stores a count value representing a target position to which a hand is to move; a rotation detecting circuit detects that a motor has rotated to output a rotation detection pulse signal and detects that the motor has not rotated to output a non-rotation detection pulse signal; a hand position counter counts the rotation detection pulse signal; and a control circuit controls the rotation of the motor with a normal pulse until the count value stored in the memory and the value counted by the hand position counter agree with each other. When a non-rotation counter counts a predetermined number of consecutive non-rotation detection pulse signals, the control circuit drives the motor with a corrective driving pulse having a great pulse width.

Abstract: The present invention provides a rotation controller adjusting the speed of a rotary member (103). Phase difference compensating means (118) outputs a phase difference compensating signal (119) corresponding to a phase difference between a rotation signal of the rotary member (103) and a target signal, and frequency difference compensating means (114) outputs a frequency difference compensating signal (115) corresponding to a frequency difference between these signals. The rotary member (103) is braking-controlled by means of these signals. Use of the phase difference compensating signal (119) permits achievement of PLL control, and maintenance within the locking range allows a stable rotation control with a high response.

Abstract: The monophase electromechanical transducer (2) includes a stator (8) and a rotor (4) including a permanent bipolar magnet (6). The stator is formed of a planar structure (10) defining first and second magnetic stator poles (18,20) and a core (12) carrying a coil (14), said core magnetically connecting first and second magnetic poles. The coil is situated in an opening (35) the edge (36) of which is closed on itself and the part of the planar structure which defines said second magnetic pole surrounds completely said opening and a hole (16) in which said bipolar magnet is situated.

Abstract: Clockwork movement fitted with a generator powering the circuit for regulating the rotation of the generator rotor. This generator is formed of at least one coil (11a, 11b, 11c) placed between magnets respectively secured to two flanges (8) mounted at the ends of a shaft of the rotor (5). The coils are arranged on a substrate (6) one part of which, carrying at least one coil, includes means allowing said coil to be moved relative to the rotor. There is also provided a device for adjusting and memorising the position of said stator part (1, 15). The adjustment of the position of said stator part allows the amplitude of the induced voltage across the terminals of the coils (11) to be adjusted.

Abstract: A control device for stepping motor including a driving pulse supplying unit for supplying a plurality of driving pulses to a driving coil for driving a rotor. A rotation detecting pulse supplying unit supplies rotation detection pulses for detecting whether the rotor rotated. A magnetic field pulse supplying unit supplies a plurality of magnetic field detection pulses for detecting the presence of magnetic field external to said stepping motor. A detection unit determines whether the driving rotor rotated and whether a magnetic field is present. An auxiliary pulse supplying unit supplies an auxiliary pulse when either rotor was not detected or when said an external magnetic field was detected. Before the driving pulse, is output, two said magnetic field detecting means magnetic field detecting pulses having different polarities are output.

Abstract: In an electronic unit having a plurality of motors, a reduction in power-supply voltage is suppressed even if the plurality of motors are driven, and a difference in hand moving timing is allowed to be made inconspicuous. An electronic timepiece having a seconds motor for driving a seconds hand and an hour-and-minute motor for driving hour and minute hands, which serves as an electronic unit, moves the seconds hand and the hour and minute hands such that, when a seconds auxiliary pulse signal is output to the seconds motor at the hand moving timing of the seconds hand, control is applied in a way in which neither magnetic-field detection around the hour-and-minute motor nor the rotation detection of the hour-and-minute motor is performed at the hand moving timing of the hour and minute hands, and an hour-and-minute auxiliary pulse signal is output to the hour-and-minute motor.

Abstract: A timepiece includes a mechanical energy source, a generator, and a train wheel connecting the mechanical energy source and the generator. The mechanical energy source drives the train wheel to cause the generator to rotate thereby creating electrical power. A rotation controller coupled to the generator controls the rotation of the generator, and includes a rotation detector for detecting the rotation of the generator and generating a rotation signal corresponding to the rotation and a reference signal generator for generating a reference signal based on a signal from a time reference source. The brake controller counts the reference signal and produces a first count, counts the rotation signal and produces a second count, and brakes the rotation of the generator when the first count is less than the second count.

Abstract: To provide an actuator which can achieve a reduction in size and weight of a device in which the actuator is mounted by amplifying and outputting displacement of a movable end of a vibrating plate as vibration in an in-plane direction, and to provide a timepiece and a notification device using the same, in an actuator (10), when a voltage is applied to a piezoelectric element (21) formed on a vibrating plate (12), the vibrating plate (12) generates bending vibrations in an out-of-plane direction, and one end portion (125) repeats displacement in an in-plane direction as a movable end. The displacement is transmitted to a lever (32) whose base end side (321) is connected to the end portion (125) of the vibrating plate (12) and an elastically deformable constricted portion (31), and a free end (322) of the lever (32) vibrates in the in-plane direction to drive a follower member (500).

Abstract: A control device for stepping motor including a driving pulse supplying unit for supplying a plurality of driving pulses to a driving coil for driving a rotor. A rotation detecting pulse supplying unit supplies rotation detection pulses for detecting whether the rotor rotated. A magnetic field pulse supplying unit supplies a plurality of magnetic field detection pulses for detecting the presence of magnetic field external to said stepping motor. A detection unit determines whether the driving rotor rotated and whether a magnetic field is present. An auxiliary pulse supplying unit supplies an auxiliary pulse when either rotor was not detected or when said an external magnetic field was detected. Before the driving pulse, is output, two said magnetic field detecting means magnetic field detecting pulses having different polarities are output.

Abstract: An output of an oscillating circuit is inputted to a system clock generating circuit, and a CPU performing various arithmetic processes is operated by this system clock. In order to operate a chopping pulse generating circuit and a one-shot pulse generating circuit, the CPU enters into an interrupt operation by means of an interrupt signal from an interrupt signal generating circuit, pulse information of a pulse rank storage circuit which stores a duty width of the chopping pulse generating circuit and pulse information of the one-shot pulse generating circuit, are independently controlled by means of rotation detection information of a rotation detecting circuit in previous driving of a motor, and the motor is driven by means of motor driving pulses formed by the chopping pulse generating circuit and the one-shot pulse generating circuit.

Abstract: In an electronic apparatus such as a timing device capable of a quick-moving operation, a detecting coil wound coaxially with a driving coil for driving a rotor is arranged, a feedback-induced voltage appearing in the detecting coil is detected by a detector circuit, and a first peak appearing first subsequent to the supply of a drive pulse and having the same polarity as the drive pulse is picked up to detect the rotation of a rotor. Based on the detected timing of the first peak, a next drive pulse is supplied, and the drive pulse is thus fast supplied while the rotation of the rotor is checked. This arrangement allows a quick-moving operation free from faulty watch hand driving to run even faster.

Abstract: The timepiece (1) includes a mainspring (2) driving the rotor (3a) of an electromechanical converter (3) and time display hands (6). A circuit (7) for enslaving the real angular position of the rotor (3a) to its desired angular position is supplied with electrical energy by the converter (3). In order to increase the autonomy of the timepiece (1), the enslaving circuit (7) includes means (28) which store a portion of the electrical energy generated by the converter (3) and means (21, 23 to 27) which use this stored electrical energy to apply driving pulses (IM) to the converter (3) when the rotor (3a) has a greater retardation than a determined retardation, with respect to its desired angular position.

Abstract: A device for controlling a stepping motor including a first drive pulse supply unit for supplying a first drive pulse to a drive coil for rotating a rotor. A rotation detecting pulse supply part supplies a rotation detecting pulse for detecting whether the rotor has rotated. An auxiliary pulse supply part supplies an auxiliary pulse having an effective power that is greater than the first drive pulse. A level adjustment pulse supply part reduces the effective power of the first drive decrements pulse after the rotor has rotated for a predetermined number of times consecutively. A second drive pulse supply part supplies a second drive pulse for a second predetermined number of time after the auxiliary pulse is supplied.

Abstract: The reference voltage of the rotation detecting comparator is set to the constant voltage circuit used in another circuit. However, because the constant voltage circuit used in another circuit has a constant voltage value suitable for its original purpose, a voltage is inputted to the rotation detecting comparator from an arbitrary location of a resistant element which is connected in series to a coil that affects a value of the rotation VRS and the non-rotation VRS. With this structure, a voltage value to be detected which is inputted to the rotation detecting comparator can be lowered as much as the resistant ratio with the voltage of the VRS per se being not changed, so that rotation or non-rotation can be detected even by the reference voltage of the constant voltage circuit which is used in another circuit.

Abstract: An analog-type electronic watch with an electrical generating apparatus, this watch having a load compensation function means, and completing avoiding the adverse influence of magnetic noise which accompanying electrical generation operation. This watch has an electrical generator which operates intermittently, an electrical generation detection means which detects electrical generation by the electrical generator based on a prescribed relationship to the operation of a drive judging means, and a control means which, when the driving judging means detects electrical generation by the electrical generator, supplies a compensation drive pulse to a drive circuit, regardless of the judgment results of the driving judging means.

Abstract: Heretofore, in an electronic clock in which a hand is moved a plurality of divisional times per minute and the hand takes one step for each one minute during a correction, when a pointer is stopped at a point other than an exact minute due to a battery replacement or the like, a time correction has been troublesome. The present invention solves the problem and provides a pointer-type electronic clock which can easily perform the time correction even if the clock is arranged so that a minute hand may be moved a plurality of times per minute. The pointer-type electronic clock has a minute hand that is moved at a plurality of divisional steps per minute in a time display state. The minute hand is moved at one step per minute in a correction state. The pointer-type electronic clock comprises minute hand position adjusting means for allowing the minute hand to be moved onto any one of each minute scale and to be then stopped when the minute hand is stopped or time is corrected.

Abstract: An electronic watch 400 which comprises a power supply 401 and a watch circuit 402.

Abstract: In an electronic timepiece using power supply means consisting of a solar cell and an electric double layer capacitor, whose output voltage varies, as a power supply, a plurality of driving pulse preparation means for preparing driving pulses for driving a stepping motor are arranged. Each driving pulse preparation means prepares a driving pulse group having a combination of pulse widths, which combination is different from that of remaining ones of the driving pulse preparation means. A varying output voltage of the power supply means is detected, and one of the plurality of driving pulse preparation means is selected in accordance with the detected output voltage. A driving pulse for minimizing the current consumption is selected and supplied to the drive circuit of the stepping motor. With this arrangement, the stepping motor can always be driven at a minimum current consumption, and the driving time can be prolonged.

Abstract: The method and the device for feeding a single-phase stepping motor for a timepiece are adapted to provide the motor (M) with a sequence of chopped voltage pulses of variable duration as a function of load conditions and of feed voltage. The sequence of chopped voltage pulses comprises in particular a supplementary sequence of partial voltage pulses of constant duration (T.sub.4), separated from each other by variable intervals (T.sub.5i) defined by a reference current (I.sub.ref) whose value is adapted as a function of the level of load of the motor.

Abstract: A viscous coupling gear device has a first case having a protrusion extending from a surface thereof, and a second case having a surface facing the surface of the first case and a protrusion extending from the surface of the second case. A gear has a driving portion for driving engagement with a first rotary member undergoing intermittent rotation and for transmitting intermittent rotation to the gear, a tubular portion extending from the gear and mounted on the protrusion of the first case for relative rotation therewith, and a tubular wall portion extending from the gear and disposed coaxially with and spaced from the tubular portion to define a cavity therebetween, the protrusion of the second case extending into the cavity and defining, together with the cavity and the tubular wall portion, a clearance. A driving member engages with a second rotary member for transmitting rotation of the gear to the second rotary member.

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 device for detecting asynchronization or stepping out of a stepping motor without making the stepping motor large in size. Parallel resonance circuit LC is provided in a recovery circuit of stator coil RL of the stepping motor for detecting linking current IX. If the stepping motor is out of step, the magnetic resistance between stator and rotor increases while the reactance of stator coil RL decreases. When motor drive current ID is turned off, a large transient current is momentarily generated yet is quickly dampened. While the motor drive current ID is off, linking current IX approaches zero. Consequently, if the stepping motor is out of step, there is no substantial difference in the linking current IX when motor drive current ID is turned on from when motor drive current ID was off. Also, the amplitude of the transient or resonance waveform is smaller than the amplitude when the stepping motor is operating normally.

Abstract: An electronic circuit for controlling an analog quartz clock, particularly for installation in automobiles, has first and second counters for generating control pulses at different rates according to whether the clock is to be operated in a normal mode, or a time-setting mode. In addition, a single 11-bit counter allows "fast" or "slow" resetting of the time by a single push button.

Abstract: To obtain an electronic clock which realizes miniaturization and low power consumption, and improves the precision of the rotation detection of a rotor by supplying a stepping motor with an effective power in accordance with the increase of a load to the stepping motor with time and performance of parts.A detect assistant pulse is supplied to the stepping motor to amplify a voltage induced by the rotational motion of the rotor which occurs after the main drive pulse is interrupted.

Abstract: The hands of the timepiece are connected to a barrel spring which also drives the rotor of a generator at a speed greater than a desired speed Vc. The electric energy supplied by the generator energizes a slaving circuit that includes a transistor which short-circuits the coil of the generator and thus brakes the rotor down to a speed less than the desired speed Vc when a comparator indicates that this rotor is ahead with respect to its theoretical angular position. A limiting circuit limits the duration of the braking action of the rotor to a fraction of the period of the a.c. voltage supplied by the generator. This arrangement ensures that the slaving circuit is adequately energized even if the rotor is substantially ahead.

Abstract: An electronic timepiece utilizing a motor to drive indicating hands is provided. The motor includes a first member having displaceable portions displaceable in a first direction. A second member moveable in a second direction is moved in the second direction by selectively coming in contact with the first member.

Abstract: A system utilizing an array of high speed video cameras with image processors coupled to data microprocessors, data memory devices, video monitors, control terminals, printout devices, and related hardware and software. The system functions to identify, track, display and record all or selected portions of the path of one or more golf balls from the time each ball is struck, or after it is in flight, until it reaches its final point of rest. The recorded tracking information may be displayed in selected forms such as video or audio replays of the actual golf shot or selected portions thereof, or by printed data in character or graphic form. The tracking information may be reviewed for detailed study of all or portions of the track of the golf shot as well as the final resting place of the ball with respect to the intended target of the shot.

Abstract: The driving device comprises two single-phase stepping motors (1, 2), each having a different preferential direction of rotation. The bidirectional drive is achieved by selectively feeding one or the other of the two motors.

Abstract: A timepiece comprising a display (2) such as a data display and a driving motor (M1, M2) for driving the display is characterized in that the driving motor comprises a piezo-electric motor directly engaging the display.

Abstract: A multifunction electronic analog timepiece includes a face and a plurality of indicators positioned on the face for displaying at least two time keeping functions. At least two step motors are provided for driving the plurality of time keeping function indicators. The time keeping function indicators are arbitrarily disposed about the face dependent upon the number of step motors and position of step motors required to drive the indicators. A microcomputer is provided and includes a program memory for storing software instructions for controlling the step motors.

Abstract: A method and device for controlling a stepping motor having a coil and a rotor with a permanent magnet magnetically coupled to the coil. A drive pulse is applied to the coil each time the rotor has to turn by one step, and a representation of the quantity of mechanical energy supplied by the motor is measured during this drive pulse. The instant when the representation of the mechanical energy passes through its maximum value is detected, and the drive pulse is interrupted at this instant. The method and device increase the operating reliability of the stepping motor.

Abstract: A high reliable multi-function analog electronic timepiece which has plurality of ultrasonic motors, or has an ultrasonic motor and a motor.A first ultrasonic motor is provided as a driving source for driving a time indicating mechanism. The control circuit controls supplying timing of driving pulses of the first ultrasonic motor for driving a time indicating mechanism and driving pulses of the second ultrasonic motor for driving the calendar indicating mechanism. The control circuit inputs a driving pulse command signal to a piezoelectric vibrator driving circuit for providing driving pulses whose generating timing is controlled to the first ultrasonic motor.The calendar indicating mechanism and the time indicating mechanism are operated by the operation of the second ultrasonic motor and the first ultrasonic motor.

Abstract: An integrated circuit for an electronic timepiece includes at least one semiconductor nonvolatile memory device. Reference data can be checked across a pair of output terminals prior to being stored in at least one EPROM to check the accuracy and acceptability of the reference data for driving a motor of the timepiece. The reference data once written into the EPROM serves as control data. Both the reference data and control data are used for controlling at least one function of the timepiece. The control data also can be checked across the output terminals to determine its accuracy and acceptability for driving the motor. Testing of the reference data and control data can be performed on a faster than real time basis.

Abstract: An integrated circuit for an electronic timepiece includes at least one semiconductor nonvolatile memory device. Reference data can be checked across a pair of output terminals prior to being stored in at least one EPROM to check the accuracy and acceptability of the reference data for driving a motor of the timepiece. The reference data once written into the EPROM serves as control data. Both the reference data and control data are used for controlling at least one function of the timepiece. The control data also can be checked across the output terminals to determine its accuracy and acceptability for driving the motor. Testing of the reference data and control data can be performed on a faster than real time basis.

Abstract: Method of supplying power to a single phase step motor of a time-piece, adapted to provide the motor with chopped voltage pulses of time-period T.sub.6 variable with respect to the load conditions and to the supply voltage of the motor, characterized in that each said impulsion of chopped voltage is composed of a sequence of elementary pulses of the same polarity and of a constant duration T.sub.4, and in that the durations T.sub.5i separating the said elementary voltage pulses vary according to load conditions and according to the supply voltage of the motor variable with respect to the load conditions and to the supply voltage of the motor.The invention finds a field of application in motors for time-pieces.

Abstract: A timepiece includes an accumulator such as a hairspring for storing the energy provided by a step motor and a control mechanism such as a rotor immersed in a viscous fluid for controlling the energy released by the accumulator to provide a constant driving force for turning the display hands of the timepiece. The accumulator and control mechanism are constructed along a common axis and are displaced from a spindle about which the display hands rotate. The spindle is positioned substantially at the center of the watch.

Abstract: An integrated circuit for an electronic timepiece includes at least one semiconductor nonvolatile memory device. Reference data can be checked across a pair of output terminals prior to being stored in at least one EPROM to check the accuracy and acceptability of the reference data for driving a motor of the timepiece. The reference data once written into the EPROM serves as control data. Both the reference data and control data are used for controlling at least one function of the timepiece. The control data also can be checked across the output terminals to determine its accuracy and acceptability for driving the motor. Testing of the reference data and control data can be performed on a faster than real time basis.

Abstract: The timepiece of this invention comprises an electromagnetic motor (100) the stator (2) of which is flat and at least partially covered by a reinforcement plate (68) of non-magnetic material or, if need be, of very low magnetic permeability which has been attached to it, preferably by welding, prior to subjecting it in bulk along with others, to reheating thereby to protect it during such operation against the risk of deformation or breakage which would render it thereafter unusable. In conformity with the invention and to avoid such plate becoming a useless extra part taking up space in the timepiece, it includes means which enable it to form at the same time another element of the timepiece. Such element may be for instance a trigger piece jumper spring (72) which cooperates with a trigger piece (212) in order to define stable positions of a manual control stem (184) which may be axially displaced.

Abstract: An electronic timepiece provides continuous rotation for a hand in response to a discrete driving rotation. An energy storage mechanism is coupled to the discrete driving rotation and converts the discrete driving rotation into stored energy. A control mechanism continuously releases the stored rotational energy as continuous rotation. A linkage coupled between the energy storage mechanism and control mechanism transmits continuous rotation therebetween and drives the hand in a continuous sweeping manner.

Abstract: A device for displaying information by means of a hand which is driven by a stepping motor rotatable in both forward and backward directions and which moves within a limited range, in which the stepping motor receives a driving signal enough to move and scan the hand in one direction in the whole range of the limited region for facilitating the attachment of the hand, and depending on the object to be measured, overtravel inhibiting circuit means are added to prevent any misdisplay.

Abstract: In a motor, in particular for the electrical driving of a clockwork, a rotor (32) which is mounted rotatably together with a shaft (3) consists of a permanent magnet having diametrically opposite permanent magnet poles. A coil arrangement in the motor comprises two coils (10 and 11) arranged at angular distances of, in particular, 90.degree. apart from each other.

Abstract: A step motor driving control mechanism for use in an electronic timepiece for reducing the current consumption thereof is provided. Load detection circuitry detects the load condition of the step motor and selectively produces a load condition signal representative of a predetermined load condition thereof. Driving and control circuitry is provided for receiving a low frequency timekeeping signal produced by a divider circuit and a load detection signal when same is selectively produced by the load detection circuitry. In response to the presence or absence of a load detection signal applied thereto, the drive and control circuitry is adapted to vary the duration of the pulse width of a drive signal applied to the step motor to effect a driving of same.

Abstract: A method for improving the efficiency of a stepping motor (1) comprising a rotor (15) having a permanent magnet (16) producing a first magnetic field, as well as a first coil (13) and a second coil (14) for supplying to the magnet (16) respectively a second magnetic field (18) and a third magnetic field (19) symmetrical to one another in relation to an axis of symmetry (7) intersecting the axis of rotation (15a) of the rotor (15).

Abstract: A two-speed battery powered quartz daylight saving clock operating for a first six months' period beginning on the shortest day of the year at two and one-half seconds per hour fast (fast time) and then being adjustable to operate for a second six months' period beginning on the longest day of the year at two and one-half seconds per hour slow (slow time) to complete each annual cycle.

Abstract: An improved drive circuit for a quartz analog wristwatch having a bipole stepping motor with a drive coil, a power supply, a gear train having a plurality of gears driven by the rotor, a plurality of output members with hands rotatably driven by said gears, the rotor, gears, output members and hands together comprising a rotating system, wherein the improvement comprises a low impedance drive coil, first circuit means arrange to generate periodic pulses of alternating polarity at a normal timekeeping frequency, second circuit means arranged to supply successive drive pulses of alternating polarity to the coil at an intermediate frequency on the order of 300 to 600 pulses per second selected to sustain and synchronize the rotating system at a substantially constant angular velocity, and third circuit means arranged to modulate the periodic pulses generated by the first circuit means so as to chop them at a high frequency on the order of 4 kilohertz at a 25 to 50 percent duty cycle selected with regard to the l

Abstract: A timepiece includes a hairspring for storing the energy provided by a step motor driving circuit and a rotor immersed in a viscous fluid controls the energy released by the hairspring to provide a constant driving force for turning the display hands of the timepiece. A frequency divider circuit counts the number of clock signals produced by an oscillator. During time correction when the hands are prevented from being driven by the energy stored in the hairspring the frequency divider retains at least a portion of the count. A recoil torque provided by the hairspring and a load torque provided by the rotor are substantially balanced at all times including immediately after the time correction activities. Time delay especially immediately following the time correction activities is avoided.

Abstract: Electro-mechanical timepiece, comprising a circuit for generating electric pulses that appear at suitable points of time, a stepper motor controlled by said pulses and comprising a rotor (2) with permanently magnetic poles (8,9), a stator (3,4,5) and a coil (6), as well as a gear driven by the action of the step motor for driving the clock hands, the stator being constructed from two stator parts (3,4) situated on either side of the rotor and a yoke (5), connecting these two parts and extending through said coil. The poles (8,9) are situated in a same cross section plane, perpendicular to the rotation axis of the rotor, and form a ring-shaped layer (14) which is thin in radial direction. According to a preferred embodiment the rotor is at the radial inner side of the poles provided with an uninterrupted round-going ring-shaped portion (7) of soft-magnetic material.

Abstract: An improved movement for a three hand quartz analog timepiece having a frame, a stepping motor with the motor pinion adapted to step once per second, and a plurality of coaxial output members rotatably mounted in the frame including a spindle for driving a "seconds" hand and having a toothed seconds wheel driven by a two-pin rotor pinion, a two-pin reduction drive pinion connected to the spindle, a coaxial sleeve having a toothed minutes wheel and a coaxial sleeves having a toothed hours wheel. The improvement comprises a dual reduction gear assembly with a single shaft rotatably mounted in the frame having a toothed third wheel driven by the reduction drive pinion and having a first reduction pinion and a second reduction pinion directly driving the hours and minutes wheel, respectively, from the same shaft. The first reduction pinion is the two-pin type and the second reduction pinion is a spur gear.

Abstract: An electronic timepiece provides continuous rotation for a hand in response to a discrete driving rotation. An energy storage mechanism is coupled to the discrete driving rotation and converts the discrete driving rotation into stored energy. A control mechanism continuously releases the stored rotational energy as continuous rotation. A linkage coupled between the energy storage mechanism and control mechanism transmits continuous rotation therebetween and drives the hand in a continuous sweeping manner.

Abstract: The hands of the timepiece are connected to a barrel spring which also drives the rotor of a generator at a speed greater than a desired speed Vc. The electric energy supplied by the generator energizes a slaving circuit that includes a transistor which short-circuits the coil of the generator and thus brakes the rotor down to a speed less than the desired speed Vc when a comparator indicates that this rotor is ahead with respect to its theoretical angular position. A limiting circuit limits the duration of the braking action of the rotor to a fraction of the period of the a.c. voltage supplied by the generator. This arrangement ensures that the slaving circuit is adequately energized even if the rotor is substantially ahead.