US2960817A - Electrical timepiece - Google Patents

Electrical timepiece Download PDF

Info

Publication number
US2960817A
US2960817A US584709A US58470956A US2960817A US 2960817 A US2960817 A US 2960817A US 584709 A US584709 A US 584709A US 58470956 A US58470956 A US 58470956A US 2960817 A US2960817 A US 2960817A
Authority
US
United States
Prior art keywords
tines
timepiece
amplitude
tine
oscillation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US584709A
Other languages
English (en)
Inventor
Hetzel Max
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bulova Watch Co Inc
Original Assignee
Bulova Watch Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bulova Watch Co Inc filed Critical Bulova Watch Co Inc
Application granted granted Critical
Publication of US2960817A publication Critical patent/US2960817A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G04—HOROLOGY
    • G04C—ELECTROMECHANICAL CLOCKS OR WATCHES
    • G04C3/00—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means
    • G04C3/08—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically
    • G04C3/10—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically driven by electromagnetic means
    • G—PHYSICS
    • G04—HOROLOGY
    • G04C—ELECTROMECHANICAL CLOCKS OR WATCHES
    • G04C3/00—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means
    • G04C3/08—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically
    • G04C3/10—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically driven by electromagnetic means
    • G04C3/101—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically driven by electromagnetic means constructional details
    • G—PHYSICS
    • G04—HOROLOGY
    • G04C—ELECTROMECHANICAL CLOCKS OR WATCHES
    • G04C3/00—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means
    • G04C3/08—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically
    • G04C3/10—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically driven by electromagnetic means
    • G04C3/101—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically driven by electromagnetic means constructional details
    • G04C3/107—Controlling frequency or amplitude of the oscillating system
    • G—PHYSICS
    • G04—HOROLOGY
    • G04C—ELECTROMECHANICAL CLOCKS OR WATCHES
    • G04C3/00—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means
    • G04C3/08—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically
    • G04C3/10—Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means wherein movement is regulated by a mechanical oscillator other than a pendulum or balance, e.g. by a tuning fork, e.g. electrostatically driven by electromagnetic means
    • G04C3/108—Driving circuits
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00—Machine element or mechanism
    • Y10T74/15—Intermittent grip type mechanical movement
    • Y10T74/1526—Oscillation or reciprocation to intermittent unidirectional motion
    • Y10T74/1553—Lever actuator
    • Y10T74/1555—Rotary driven element

Definitions

  • the present invention relates to an electrical timepiece.
  • the present invention relates to an electrical timepiece incorporating a motion transformer capable of transforming the oscillations of a vibrator into rotary movement, which vibrator is oscillated by suitable means which are operatively associated therewith, the electrical timepiece being of the type disclosed in copending applications Serial No. 436,949 filed June 15, 1954, Serial No. 547,510 filed November 17, 1955 (said application Serial No. 547,510 being a co'ntinu'ation of application Serial No. 463,462 filed October" 20, 1954, now abandoned), Serial No; 565,451 filedFebruary 14, 1956, now Patent No. 2,888,582, May 26, 1959 Serial No, 565,452 filed February 14, 1956, Serial No. 570,958 filed March 12, 1956, and Serial No. 580,813, fi-l'ed' April 26, 1956 and entitled Motion Transformer, now Patent No. 2,908,174; October 13, 1959.
  • This application is acon tinuation-in-p'art of said copending application Serial No; 580,813.
  • the objects of the present'invention also include the provision of an electric timepiece wherein suitable means are provided for oscillating the vibrator which serves to cause rotary movement of the hands of the timepiece.
  • the objects of the present invention further include the provision of an electric timepiece which may be easily assembled and constructed and thus'be readily mass produced;
  • an electric timepiece whichis extremely accurate and reliable in-operation and which will operate for very. long periods without requiring winding oranyothe'r attention whatsoever.
  • the present invention resides in that improvement in such a timepiece wherein the driving means are operatively associated with the timepiece mechanism in such a manner that the timepiece mechanism is-drivenjby the driving means when the length of the stroke ofreciprocation thereof is between a predetermined minimum stroke length and a predetermined maximum stroke length, wherein the vibrator reciprocates' the driving means with a stroke the length of which is a function of the amplitude of oscillation of the vibrator, and wherein the means for oscillating the vibrator are electrical means and oscillate the" vibrator at an amplitude at which the stroke length of the driving means is between the predetermined minimum and maximum stroke lengths.
  • Fig.- l is a plan view of the interior of a timepiece according to the present invention when seen from the rear Off the timepiece.
  • Fig; 1 showing diagrammatically how the electrical leads may be connected to a storage battery orthe'like when the timepiece is used, for example, as'an automobile clock,
  • Fig. 1 further showing the timepiece as incorporating one preferred embodiment of a motion transformer mechanism capable of transforming oscillations of a vibrator to rotary motion; 7
  • Fig. 2 is a'sectional elevational view taken along line ABCDEF of Fig. 1 in the direction of the arrows;
  • Fig. 3 is a side elevational view of the structure of'Fig. 1 as seen from the left sideof the latter;
  • Fig. 4 is a fragmentary plan view similar to Fig. 1 showing" a variation according to which the structure of Fig. 1 may be connected'to a'diflerent source of electrical y;
  • Fig. 5 is a fragmentary perspective view of a part of a pawl of the'pres'ent invention as'seen in the direction of arrow G of Fig. 1;
  • Fig. 6' is a perspectiveview illustrating the connection of a pawl to the tine of a tuning fork, the structure of Fig. 6 being shown in the direction of arrow H of Fig. 1;
  • Fig. 7 is a wiring diagram of the electrical circuit of the timepiece shown in Figs. 1 to 6;
  • Fig. 8 is a diagrammatic view illustrating the interaction of a pawl and ratchet wheel incorporated in a motion transformer of the type illustrated in Fig. 1;
  • Fig. 9 is a diagrammatic showing of a modified embodiment of the present invention.
  • Fig. 10 is a diagrammatic view of another modified embodiment of the present invention.
  • Fig. 11 is a diagrammatic view of yet another modified embodiment of the present invention.
  • Fig. 12 is-a fragmentary diagrammatic view of a still further modified embodiment of the present invention.
  • Fig. 13 isa fragmentary diagrammatic view of yet another modified embodiment of the present invention.
  • Fig. 14 is a fragmentary diagrammatic view of a modified embodiment of a motion transformer mechanism incorporated in a timepiece of'the type illustrated in Fig. 1;
  • Fig. 15 is a fragmentary diagrammatic view, on an enlarged scale, of another modified embodiment of a motion transformer mechanism
  • Fig. 16 is a fragmentary diagrammatic view, on an en- 3 larged scale, of yet another modified embodiment of a motion transformer mechanism
  • Fig. 17 is a sectional view taken along line A-A of Fig. 16;
  • Fig. 18 is a fragmentary diagrammatic view, on an enlarged scale, of a still further modified embodiment of a motion transformer mechanism
  • Fig. 19 is a fragmentary diagrammatic view, on an enlarged scale of a still further modified embodiment of a motion transformer mechanism
  • Fig. 20 is a fragmentary perspective view, partly in section and on an enlarged scale, of a tuning-fork type vibrator, a pawl and ratchet type motion transformer mechanism actuated by the vibrator, and electrical means for oscillating the vibrator;
  • Fig. 21 is a wiring diagram of the electrical circuit of the electrical means shown in Fig. 20.
  • Fig. 22 is a graphical representation of certain voltages and currents as a function of time.
  • the timepiece includes a base plate 1 which is made of a circular plate having a substantially constant thickness.
  • a vibrator 2 which is preferably of a tuning fork type is fixed to a member as by soldering or welding or the like, this member 5, in turn, is fixed to the base plate 1 by a pair of screws 5a.
  • the member 5 is connected to the tuning fork 2 only at that part thereof which interconnects the tines 3 and 4, so that the latter are maintained in spaced relation to the base plate 1 and are free to oscillate.
  • a permanent magnet 6 in the form of a hollow cylinder which is open at one end and which has an end wall 6b closing the cylinder 60, this end wall 612 carrying a magnetic bar 6a which is of very strong magnetic material, as for example, Alnico.
  • the other tine 4 of the tuning fork 2 carries at its free end a balance weight 7 which may simply be in the form of a cylindrical block fixed in the manner shown in Fig. 1 to the free end of the tine 4.
  • the tines 3 and 4 and the masses of the permanent magnet 6 and the balance weight 7 are so chosen that the tine 3 and the permanent magnet 6 on the one hand and the tine 4 and the balance weight 7 on the other hand have approximately the same natural frequency so that the tuning fork will not require an undesirable large amount of damping.
  • the arrangement of the parts is such that the centers of gravity G of the permanent magnet6 and the balance weight 7 are in alignment with the tines 3 and 4, respectively.
  • the counter weight 7 carries an abutment element 7b which is preferably made of non-magnetic material, as, for example, brass.
  • the abutment element 7b extends toward the permanent magnet 6 and is spaced therefrom a distance s.
  • the tines of a vibrating tuning fork type vibrator normally oscillate toward and away from each other, i.e., inward movement of one tine from its normal rest position is accompanied by a corresponding inward movement of the other tine and outward movement of one tine is accompanied by a corresponding outward movement of the other tine.
  • the inward deflection of each tine is equal to its outward deflection, so that the amplitude of oscillation of each time is equal to twice the deflection of each tine from its rest position to its inner deflected position.
  • each tine 3 and 4 is equal to the length of the distance s inasmuch as the maximum possible inner deflection of each tine is equal to one-half s.
  • suitable abutments 3a and 4a are carried by the base plate 1 and serve to limit the outwardmost deflection of the tines 3 and 4, respectively.
  • the distances between the abutment 3a and the time 3 and between the abutment 4a and the tine 4 are considerably greater than the above described distance s, so that the tines will engage these abutments only when the timepiece is exposed to excessive shocks.
  • the abutments are normally not contacted by the tines but serve only to protect the same from damage in the event the timepiece is subjected to very large shocks.
  • the balance weight 7 may be provided with a threaded bore 7a in which a screw member 8 is threadedly located.
  • the screw member 8 is shorter than the length of the threaded bore so that the screw member may be shifted toward or away from the tine 4 along a line forming an extension of the latter.
  • the center of gravity of the balance weight 7 is shifted along this line simply by varying the position of the screw 8.
  • the natural frequency of the tine 4 may be varied, the center of gravity of the balance weight 7, however, at all times remaining in registration with the tine 4.
  • the natural frequency of the entire tuning fork 2 is the average of the natural frequency of the two tines, it is possible to change the natural frequency of the entire tuning fork by shifting the screw 8.
  • a tubular carrier 10 which is fixed to a support 13, the latter in turn being fixed to the base plate 1 by means of screw members 14, as is shown in Figs. 1 and 3.
  • the tubular member 10 freely surrounds the core 6:: without contacting the latter, and the tubular member 10 carries a pair of coils 11 and 12, the coil 12 having approximately five to six times as many turns as the coil 11.
  • the core 6a has suflicient clearance within the tube 10 to avoid contacting the latter during oscillations of the tines 3 and 4 of the tuning fork.
  • the coils form with the permanent magnet 6 a transducer which, together with the tuning fork 2, forms a tuning fork oscillator of the same general type as that disclosed in copending application Serial No. 436,949.
  • a resilient strap 33 which serves to mount on the support 13 a capacitor 34, a resistor 35, a transistor 19, and a capacitor 40. Furthermore, the support 13 carries a pair of insulated electrical terminals 15 and 16 which are electrically connected to the lines 22 and 23 which in turn are connected to a source of electrical energy.
  • the source of energy is the storage battery 17 of an automobile. In general the voltage of such an automobile battery is too great for the purposes of operating a timepiece of the type disclosed, so that this battery is not connected directly to the timepiece.
  • the lines 22 and 23 are com 3 nec'tedin the manner shown in Fig.
  • the electrical circuit When the above described electronic circuit is connected to the source of energy, the electrical circuit is closed and the oscillations of the tuningfork are started and are maintained by the sourceof energy.
  • the tuning fork starts oscillating as soon as the circuit is closed because it is quite sensitive and picks up any vibrations which are present in the surrounding atmosphere or in the base plate 1.
  • the oscillations of the tuning fork must be converted into a rotary movement in order to be useful in the timepiece, and this conversion can take place by the transmission means illustrated. in Figs. 1, 2, 5 and 6.
  • a pawl 20 is carried by the tine 4 of the tuning fork 2, this pawl 26 being in the form of a relatively light leaf spring and being fixed to the tine 4 by means of a pin 20, as shown in Fig. 6.
  • the tine 4 is formed with a relatively shallow bore which does not extend more than one quarter of the way through the tine 4 and into which bore the pin 20' is pressed, so that in this way the natural frequency of the tine 4 is influenced to but a very negligible extent.
  • the leaf spring 2% is fixed to the pin 20', as by being soldered thereto, in the manner shown in Fig. 6, and at its free end leaf spring 20 carries the tooth member 20a made of a very hard material such as glass or hardened steel.
  • the member 20a is wider than the leaf spring 20 and extends beyond the latter, and this member 215a is fixed to the leaf spring 29 by a suitable adhesive material, for example.
  • the member Zila is preferably formed with a sharp edge.
  • This member 20a of the pawl cooperates with the teeth of the ratchet wheel 21 so that the oscillations of the tine 4 transmit turning impulses to the ratchet wheel 21 through the pawl 20. In this way the ratchet wheel 21 is turned through a predetermined angle at every oscillation.
  • the ratchet wheel 21 and the pinion 21a are fixed to a common shaft which extends through the base plate 1.
  • this common shaft extends through an opening of a dished spring 33 which bears against part of the ratchet wheel 21 and urges the latter away from the base plate 1, so that dished spring 33 acts as a brake retarding the turning movement of the ratchet wheel 21.
  • the spring 33, the ratchet whee 21, as well as the pawl 29 and member 20a are carefully designed and chosen so that at each oscillation the turning movement transferred to the ratchet wheel 21 by the leaf spring 20 will result only in a turning of the ratchet wheel in the desired direction through a distance of one tooth.
  • the arrangement is such that the ratchet wheel 21 cannot overrun or turn freely beyond the distance through which it is turned by the pawl.
  • the frictional resistance provided by the spring 33 is such that during the return movement of the pawl 20 the ratchet wheel 21 also does not turn and the tooth member 2&2 runs over a tooth of the ratchet wheel, to engage in the next space between the teeth.
  • the ratchet wheel 21 also turns at a constant speed and in one direction.
  • a gear train is provided to trans mit the turning of the ratchet wheel 21 to the hands of the clock, and this gear train includes the pinion 21a, the
  • gear 22 meshing with the pinion 21a and turning together with the pinion 22a which meshes with the gear 23 which turns together with the pinion 23a.
  • the pinion 23a meshes with the gear 24 which turns the pinion 24a, the latter meshing with the gear 25 which turns together with the pinion 25a.
  • the gear 25 is fixed as by a press fit to the shaft 251) to which the pinion 25a also is fixed, and this shaft 25b extends all the way up to the unillustrated' face of the clock which carries the numbers.
  • the frequency of oscillations of the tuning fork and the number of teeth of the ratchet wheel 21 as well as the different transmission ratiosbetween the several driving and driven gears are so chosen that the shaft 25b makes one complete revolution in an hour.
  • the minute hand is fixed to the shaft 25b.
  • the speed of the minute gear 25 is reduced to one twelfth in a known way.
  • the gear 25a meshes with a gear 26 which turns together with the pinion 26a, the latter in turn meshing with a gear 27 aflixed to the sleeve 28 freely turnable on the shaft 25b.
  • These gears 25a, 26, 26a, and 27 give to the sleeve 28 a speed of rotation which. is one twelfth that of the shaft 25b, so that the sleeve 28 turns through a complete revolution in twelve hours, and thus the hour hand is fixed to the sleeve 28.
  • the various pinions and gears can have the following numbers of teeth to provide the desired transmission to enable accurate time to be kept from the tuning fork.
  • Pinion or gear Number of teeth Ratchet wheel 21 360 Pinion 21a 6 Gear 22 30 Pinion 22a 6 Gear 23 a- 36 Pinion 23a 6 Gear 24 42 Pinion 24a 6 Minute wheel 25 50 Pinion 25a 10 Gear 26 30 Pinion 26a 8 Hour wheel 27 32 A consideration of the above numbers of teeth will show that the minute wheel makes one revolution an hour and the hour wheel makes one revolution in-twelve hours.
  • Fig. 4 shows an arrangement where the base plate 1 is provided with a depression which receives a miniature battery 32 which may have a terminal voltage of 1.3 volts, and this battery 32 is maintained within the depression 32a of the base plate 1 by an electrically conductive springy member 30 which is affixed by a screw 31 to a block 29 of insulating material, this block being fixed in a known way as by a screw or the like to the base plate 1.
  • the force of the spring 30 keeps the battery 32 in position within the recess 31.
  • the casing of the battery 32 which engages the electrically conductive base plate 1 forms the negative pole of the battery while the positive pole thereof is formed by the cover of the battery which engages the member 30.
  • This member 30 is insulated from the base plate 1 by the block 29, although if desired the member 30 can also be insulated from block 29 and screw 31 in any suitable way as by suitable washers and a suitable sleeve into which the screw 31 extends.
  • the electrically conductive springy member 30 is connected with a suitable lead to the positive terminal 16 carried s by the support 13 while the negative terminal 15 is in this case connected electrically with the base plate 1.
  • Fig. 7 is a wiring diagram illustrating the electrical circuit of themeans for oscillating the tines of the vibrator.
  • These means include a transistor which is preferably a germanium junction-type transistor, the base, emitter and collector electrodes of which are indicated at B, E, and C respectively.
  • the positive terminal 16 of the voltage source (not shown) is electrically connected to the emitter E while the collector C is connected to one terminal of the coil 12 which is approximately five to six times the number of turns of the coil 11, as was pointed out above.
  • the other terminal of the coil,12 is connected to the negative terminal 15 of the voltage source.
  • a capacitor 40 is connected in parallel with the coil 12, the capacitance of the capacitor 40 and the inductance of the coil 12 being so selected that the capacitor 40 and the coil 12 together form a tuned circuit which has a resonant frequency that corresponds substantially to the natural frequency of oscillation of the vibrator. In this way, the capacitor 40 serves to prevent undesired oscillations. Also, the capacitor 34 and resistor 35 are connected in parallel with each other and this parallel circuit is serially connected to one terminal of the coil 11 and to the negative terminal 15 of the voltage source. The circuit is completed by connecting the other terminal of the coil 11 to the base B of the transistor.
  • the above circuit is a self-regulating one in that it will cause the tines to vibrate not only at their natural frequency, but also at a substantially constant amplitude.
  • the amplitude of oscillation of the tines will be maintained between certain predetermined minimum and maximum amplitudes. The significance and desirability of this will become evident upon further consideration of the specification.
  • the reciprocation of the pawl is brought about by the oscillation or vibration of the vibrator 2, the length of the stroke of reciprocation of the pawl being a function of or dependent upon the amplitude of oscillation of the tine 4.
  • the arrangement of the parts is such that normally each reciprocation of the pawl brings about an angular rotation of the ratchet wheel which corresponds to the pitch of each ratchet tooth.
  • the stroke length of the pawl must not only be sufiiciently great so that the pawl will, during successive reciprocation, engage different teeth, but also, the stroke length of the pawl should not be so great that the pawl engages, during successive reciprocations, non-successive teeth.
  • the pawl should move in such a manner that the tooth 20a, in a direction T tangential to the ratchet wheel at the point of engagement between the tooth 20a and the ratchet wheel, reciprocates with a stroke the length of which is greater than the distance P and smaller than twice this distance, the distance P representing the pitch of the ratchet teeth. It is clear that if the tooth 20a does not reciprocate with a stroke the length of which exceeds the distance P, the tooth 20a would not, during successive reciprocations, engage successive teeth but would instead simply remain in engagement with the same tooth.
  • the stroke length of the tooth 20a in the direction T is a function of or is dependent upon the amplitude of oscillation of the tine 4.
  • the tine 4 will have to oscillate with a certain minimum amplitude.
  • the above described electrical means shown schematically in Fig. 7 are capable of oscillating the tine 4 at at least such minimum amplitude.
  • the stroke length of the tooth 20a in order for the stroke length of the tooth 20a not to exceed 2P, and, in practhe, not to exceed a length 0 which is somewhat smaller than 2P, the amplitude of oscillation of the tine 4 may not exceed a certain maximum.
  • the above described electrical means are so constructed as to oscillate the tines at an amplitude which does not exceed a certain operating or normal maximum, which corresponds to reciprocation of the tooth 20a with a stroke length shown at b.
  • the stroke length I is not only smaller than 2P but is also somewhat smaller than the stroke length 0.
  • shocks or other extraneous forces to which a timepiece is very often exposed may be sufficient to cause the tine 4 to oscillate at an excessive amplitude, i.e., at an amplitude which exceeds that normal maximum and which causes the tooth 20a to reciprocate with a stroke length greater than b.
  • excessive oscillation may, prior to being damped to below the normal maximum amplitude, persist throughout a considerable number of cycles during each of which the ratchet wheel is advanced an angular distance exceeding that corresponding to the pitch P.
  • the abutment 7b is therefore provided, and serves to prevent the tines 3 and 4 from oscillating above an amplitude corresponding to the distance s, as set forth above. Accordingly, the distance s is so selected that the tines 3 and 4 may oscillate at an absolute maximum amplitude which corresponds to reciprocation of the tooth 20a, in the direction T, with a stroke length less than 2?, for example with the stroke length shown at c.
  • the tooth 20a cannot, during oscillation of the tuning fork, skip any of the teeth 21a of the ratchet wheel 21, irrespective of whether the tooth 20a is reciprocated by the tine 4 during normal oscillation thereof under the influence of the above-described electrical means or whether the tooth 20a is reciprocated by the tine 4 during excessive oscillation thereof under the influence of extraneous vibrations. Consequently, each oscillation of the tuning fork and consequently each reciprocation of the pawl 20 brings about an angular movement of the ratchet wheel 21 which corresponds to the pitch P of the ratchet teeth 21a, as disclosed in copending application Serial No. 570,958.
  • the electrical means for oscillating the tuning fork are so constructed and arranged that the tines are oscillated at such amplitude as will bring about reciprocation of the tooth 20a in the direction T with a stroke length equal to approximately 1.5P.
  • the forwardmost position of the tooth 20a is shown in solid lines whereas the normal backwardmost position is shown in dotted lines.
  • the electrical means normally oscillate the tines at the amplitude, or within the amplitude range, necessary to cause reciprocation of the tooth 20a with the proper stroke length.
  • the abutment element 7b is thus called upon to limit the amplitude of oscillation of the tines to the above described absolute maximum only when the timepiece is exposed to shocks or other extraneous forces of such mag- 9 nitude as to cause the tines to oscillate at an amplitude greater than the normal maximum amplitude.
  • the tuning fork 102 having tines 103 and 104 is adapted to be mounted on the base plate of the timepiece mechanism by means of the member 105, the latter being screwed onto the base plate by means of screws 105a.
  • the tines 103 and 104 respectively carry a permanent magnet 106 and a balance weight 107, the respective centers of gravity of these members being in registration with the respective tines.
  • the time 104 carries a pawl 120 having a tooth 120a, as described above.
  • the instant embodiment differs from the above described one in that the abutment element 1071; instead of being carried by the balance weight 107 is carried by the permanent magnet 106.
  • the element 107 may be made of nonmagnetic material, such as brass.
  • the element 107 may be made of magnetic material but be magnetically insulated from the permanent magnet 106 by means of a partition element 107b which is made of nonmagnetic material.
  • the right free end of the element 107b, as viewed in Fig. 9, is spaced a distance s from the balance weight 107, and the function and mode of operation of the device is identical to that of the above described embodiment.
  • the tuning fork 202 having tines 203 and 204 is adapted to be secured to the base plate of a timepiece by means of a member 205, the latter being screwed onto the base plate by means of screws 205a.
  • the tine 204 carries a pawl 220 having a tooth 220a adapted to cooperate with the ratchet wheel in the manner described above.
  • the tines 203 and 204 each carry a permanent magnet 206, the respective centers of gravity of which are in alignment or registration with the respective tines, so that the instant embodiment differs from the above described one in that two permanent magnets are provided, there being no balance weight corresponding to the element 7 of Fig. 1.
  • the electrical means for oscillating the tuning fork may be of the constructions described in the above mentioned copending application Serial No. 436,949.
  • One of the permanent magnets 206 carries an abutment element 207k which is spaced from the other permanent magnet a distance s, the function and operation of the device being identical to the above described ones.
  • the tuning fork 302 includes a pair of tines 303 and 304, the axis of symmetry of the tuning fork being indicated by the line X-X.
  • a member 305 serves to mount the tuning fork onto the base plate of a timepiece, as, for example, by means of screws 305a.
  • the tines of the tuning fork are inclined toward each other and converge toward each other as they approach their free ends so that the tuning fork 302 has the substantially triangular configuration indicated in Fig. 11.
  • a pair of permanent magnetic drums 306 are fixed at their end faces respectively to the outer faces of the free ends of the tines, it being understood that one of the drums 306 may be replaced by a suitable balance weight of the type described in connection with the embodiments illustrated in Figs. 1 and 9.
  • the arrangement of the parts is such that the center of gravity of each gnet is spaced a distance D from the axis of symmetry XX. This distance is so selected as to be substantially equal to the distance D which is the distance that each point T is spaced from the axis of symmetry XX.
  • the point T of each tine represents that axis about which the center of gravity of each magnetic drum or balance weight oscillates or pivots. In practice, the axis T of each tine will be located in the lowermost third of the tine.
  • the tine 304 carries a pawl 320 having a tooth 320 2 which is adapted to cooperate with a ratchet wheel, in the manner described above, and one of the tines carries the abutment element 30712 which is fixed to the inner face of the free end portion of the tine.
  • the free end of the abutment element 30712v is spaced a distance s from the inner face of the free end portion of the other tine so as to limit the maxiamplitude of oscillation of the tuning fork.
  • each of the tines 403 and 404 carries a permanent magnet 406, it being understood that one of the permanent magnets may be replaced by a suitable balance weight.
  • the instant embodiment differs from the above described ones in that each of the permanent magnets 406 carries an abutment element 407b, these elements being spaced from each other a distance s and cooperating with each other in such a manner that when the amplitude of oscillation of the tines is equal to the maximum permissible amplitude, the abutment elements will engage each other thereby preventing the tines from oscillating at an amplitude greater than this maximum amplitude.
  • each of the permanent magnets 506 either carries or is formed with an abutment portion 507! which may be substantially frusto-conical or domeshaped as shown in Fig. 13. The respective inwardmost parts of the portion 507!) are spaced from each other a distance s, thereby limiting the maximum amplitude of oscillation of the tines.
  • any suitably shaped abutment means may be provided for limiting the maximum amplitude of oscillation of the tines.
  • the abutment means may be connected to or be integral with the tines proper.
  • the abutment means it is not essential that the abutment means be located between the free end portions of the tines, and they may be so arranged as to be located physically exteriorly of the space between the tines.
  • Figs. 14 to 19 illustrate. on an enlarged scale, different embodiments of motion transformer mechanisms a apted to be incorporated in a timepiece of the character described.
  • the structural deta ls of the timepiece including the tuning-fork type vib ator, the electrical means for oscillating the tines, and the abutment means for limiting the maximum amplitude of oscillation of the tines may be identical to any of the above-described arrangements.
  • the motion transformer mechanisms shown in Figs. 14- 19, wh ch are disclosed in copending applications. Serial Io. 547,510 and Serial No.
  • the tuning fork has a pair of tines 603 and 604 carrying a magnetic drum 606 and a balance weight 607, respectively, the latter carrying an abutment element 607! the free end of which is spaced at distance s from the drum 606 when the tines are at rest.
  • the tine 604 also carries a driving means composed of a leaf spring 620 firmly secured at one end to the tine 604 and a friction element 620a carried by the leaf spring 620 at its free end.
  • the triotion element 620a may be made of a suitable synthetic material or of a precious or semi-precious stone, as, for
  • the ratchet wheel 621 which is rotatably mounted at 621a and serves to drive the timepiece mechanism of the timepiece.
  • the crests constitute a discontinuous outer peripheral friction surface so that when the driving means is reciprocated in a direction T tangential to the ratchet wheel at the point of engagement between the friction element 620a and the ratchet wheel, the ratchet wheel is oscillated about its turning axis 621a.
  • the ratchet wheel is rotated in a counter-clockwise direction, shown by arrow 640, when the driving means moves leftwardly, as viewed in Fig. 14, whereas the ratchet wheel is rotated in a clockwise direction, shown by arrow 640a, when the driving means moves rightwardly.
  • a pawl means is provided for limiting the ratchet wheel 621 to continuous rotation in the direction of the arrow 640.
  • the pawl means includes a leaf spring 630 firmly secured at one end to the timepiece base plate 601 and a pawl element 630a carried by the leaf spring 630 at its free end.
  • the pawl means prevents rotation of the ratchet wheel 621, in the direction of the arrow 640a, an angular distance exceeding an angular distance corresponding to the pitch P, so that continuous rotation of the ratchet wheel is limited to rotation in the direction of the arrow 640. It will also be understood that in order for each oscillation of the tine 604 to be accompanied bv angular displacement of the ratchet wheel a distance corresponding to the pitch P, the length of the stroke of reciprocation of the driving means should be not less than P and not greater than 2P.
  • the stroke length of the driving means is a function of or dependent upon the amplitude of oscillation of the tines of the vibrator, so that the tines will have to oscillate with a certain minimum amplitude to cause the driving means to reciprocate with a stroke length at least equal to P.
  • the above described electrical means shown in Fig. 7 are capable of oscillating the tine 604 at at least such minimum amplitude.
  • the distance s is so selected that the absolute maximum amplitude of oscillation of the tines is one at which the stroke length of the driving means does not exceed 2P.
  • the electrical means will oscillate the tines at an amplitude not exceeding a normal maximum amplitude which is not only smaller than 2P but which is also smaller than the absolute maximum at which the tines may oscillate.
  • the abutment element 6071 serves mainly to prevent excessive oscillation of the tines in the event the timepiece is exposed to relatively severe shocks or other extraneous forces.
  • the electrical means are so constructed as to oscillate the tines with such an amplitude that the driving means reciprocates with a stroke length equal to approximately 1.5P. It will be understood from the above that the pawl means will, during successive reciprocations of the driving means, be engaged by successive ratchet teeth.
  • each oscillation of the tines first displaces the ratchet wheel 621, in the direction of the arrow 640, an angular distance corresponding to approximately 1.5P and thereafter, in the direction of the arrow 640a, an angular distance corresponding to approximately 0.5P.
  • the net or effective displacement of the ratchet wheel during each oscillation of the tines is therefore an angular distance corresponding to exactly 1.0P in the direction of the arrow 640, so that the timepiece mechanism is driven at a rate directly proportional to the frequency of oscillation of the vibrator. Since the same has an extremely high degree of constancy, the timepiece mechanism is driven very accurately.
  • the natural frequency of the driving means is considerably greater than that of the vibrator.
  • the natural frequency of the leaf spring 620 and the friction element 62044 should be at least twice as great as that of the tines of the vibrator.
  • the tuning fork has a pair of tines 703 and 704 carrying a magnetic drum 706 and a balance weight 707, respectively.
  • the balance weight carries an abutment element 707k the free end of which is spaced a distance s from the drum 706 when the tines are at rest.
  • the tine 704 further carries a driv ing means constituted by a leaf spring 720 firmly secured at one end to the time 704.
  • the free end of the leaf spring 720 is adapted frictionally to engage the outer peripheral friction surface 721b of a friction wheel 721b which, together with the ratchet wheel 721, forms a rotary means for driving the timepiece mechanism, the rotary means being turnably mounted on the base plate of the timepiece at 721a.
  • a pawl means is provided for limiting the rotary means to continuous rotation in the direction of the arrow 740.
  • the pawl means includes a leaf spring 730 firmly secured at one end to the base plate 701 and a pawl element 730a carried by the leaf spring 730 at its free end.
  • the tuning fork has a pair of tines 803 and 804 carry ing a magnetic drum 806and a balance weight 807, respectively.
  • the balance weight carries an abutment element 80717 the free end of which is spaced a distance s from the drum 806 when the tines are at rest.
  • the tine 804 is connected to a driving means for converting the oscillations of the vibrator to rotation of the ratchet wheel 821 which is rotatably mounted on the timepiece base plate 801 at 821a.
  • the driving means includes a wire one end of which is fixed to the tine 804 and the other end of which is fixed to a coil spring 820a, the latter being secured to the base plate.
  • the mounting of the coil spring 820:: is such that one of its ends is introduced into a bore within which it is retained by a tapered pin or wedge 801a.
  • the tension of the spring 820a and consequently the tension of the wire 820 may be adjusted.
  • the wire 820 thus reciprocates during oscillation of the tines of the vibrator, the coil spring 820a being tensioned during leftward movement of the tine 804 and serving to draw the wire 820 during rightward movement of this tine.
  • the wire 820 seats within the longitudinal groove 850a of a friction element 850, the underside of which bears with a slight pressure on the discontinuous outer peripheral friction surface of the ratchet wheel formed by the crests of the ratchet teeth.
  • the friction element 850 is preferably of a very light material and may have its underside lined with a suitable plastic material 8501; in order to improve the friction between the underside of the friction element and the ratchet teeth and also so as to prevent excessive Wear of the underside.
  • the friction between the friction element 850 and the wire 820 is sufliciently great so that the friction element moves with the wire and thus reciprocates during oscil lation of the vibrator.
  • the ratchet wheel 823 is turned in a counter-clockwise direction, shown by arrow 840, and when the friction element 850 moves rightwardly, the ratchet wheel is turned in a clockwise direction, shown by arrow 840a.
  • Suitable pawl means are provided for preventing continuous rotation of the ratchet wheel 821 in the direction of the arrow 840a, and may include a very thin resilient w en leaf 806 preferably made of a plastic, one end of which leaf bears with a slight pressure on one of the ratchet teeth.
  • the length of the stroke of reciprocation of the friction element 850 should be at least as great as P and not greater than 2P, with P being the pitch of the ratchet teeth of the ratchet wheel 821. While the maximum amplitude of oscillation of the tines is determined by the distance r, it is possible, according to the instant embodiment, to limit the stroke length of the friction element 350 directly, i.e., independently of the maximum possible amplitude of osciilation of the tines.
  • abutments or stops 860 and 861 adapted to be engaged by the opposite end-s of the friction element 350, respectively.
  • the distance between the stops S60 and 861, in the direction T, is greater than the length of the friction element 850 and, in any one position of the friction element, one of its ends is spaced a distance d from the stop 860 and the other of its ends is spaced a distance d from the stop 861.
  • the maximum length of the stroke of reciprocation of the friction element 850 is equal to d-l-d'. This sum should, for the reasons set forth above, be less than 2?.
  • the tines are oscillated at such amplitude that the stroke length of the friction element 850 is approximately 1.5P, so that the stops 860 and 861 are engaged only when, as a result of shocks, excessive oscillations are imparted to the tine.
  • the friction element will, at each end of the stroke, engage one of the stops, the wire 820 being free to slide relative to the friction element when movement thereof is prevented. In this way, shocks occurring when the friction element 850 engages the stops 860 and 861 are dampened.
  • the natural frequency of the moving parts such above described one in that the friction element 950 is fixed to the wire 920.
  • the latter is connected at one end to the base plate by means of a coil spring 920a and at the other end to the tine 9134 by means of another coil spring 9201). In this way, shocks occurring when the friction elements 950 engages the stops are dampened.
  • the natural frequency of the moving parts should be higher than the frequency of oscillation of the vibrator.
  • the wire is so disposed that the friction element bears on the ratchet wheel with sufficient pressure to impart a rotary movement thereto. In some cases, it may be desirable to exert an additional pressure on the friction 14 element in order to insure good frictional contact between the element and the teeth of the ratchet wheel.
  • Such positive contact may be attained in either of the arrangements shown in Figs. 16 to 18 by means of the construction shown in Fig. 19.
  • An arched leaf spring 1060 is fixed at one end to the timepiece base plate by means of a pin or screw 1061, the other end of the spring bearing on the upper side of the friction element 1050.
  • the spring 1060 is convex toward the tine 1004 so that when the friction element 1050 moves leftwardly, i.e., in a direction which brings about rotation of the ratchet wheel 1021 in the direction of the arrow 1040, the spring 1060 is compressed and exerts a greater force on the friction element 1050, whereas when the friction element moves rightwardly, i.e., in a direction which tends to bring about rotation of the ratchet wheel in the direction of the arrow 1040a, the pressure exerted by the spring 1060 tends to reduce.
  • any one of these motion transformers may incorporate any suitably shaped vibrator, as, for example, any one of the types shown in Figs. 9' to 11.
  • any one of motion transformers shown in Figs. 14 to 19 may be used in conjunction with a tuning-fork type vibrator each tine of which carries a magnetic drum rather than a tuning-fork type vibrator wherein one tine carries a magnetic drum and the other tine carries a balance weight.
  • the abutment means carried by the tines may include one or two abutment elements, or be otherwise suitably shaped, as, for example, in the manner described above and illustrated in Figs. 9 to 13.
  • Fig. 20 is a fragmentary perspective view, partly in section and on an enlarged scale, of a tuning-fork type vibrator 1102, and electrical means for oscillating the same.
  • the instant embodiment differs from that shown in Fig. 1 in that each of the tines 1103 and 1104 carries an electric component which is part of the electrical means, there being no balance weight corresponding to the element 7 of Fig. 1.
  • the vibrator is operatively associated with a driving means which forms part of a motion transformer for converting oscillations of the vibrator to rotary movement of the hands of the timepiece.
  • the motion transformer is of the pawl and ratchet type shown, for example, in Fig. 1, but it will be understood that the vibrator may be used in conjunction with any suitable type of motion transformer, including any one of the types shown in the preceding figures.
  • the pawl and ratchet mechanism shown in Fig. 20 includes a pawl 1120 carried by the tine 1104, a tooth 1120a being provided at the free end of the pawl.
  • the tooth cooperates with the ratchet teeth 1121a of a rotatably mounted ratchet wheel 1121 in such a manner that the ratchet wheel is caused to rotate in the direction of the arrow 1140 during oscillation of the tine 1104.
  • a friction wheel 1121b which is mounted for rotation to- .gether with the ratchet wheel 1121 is engaged by a leaf spring 11210 which is carried by the base 1101 of the timepiece.
  • the friction wheel 1121b and leaf spring 1121c constitute a brake for preventing rotation of the ratchet wheel under the influence of anything other than the pawl 1120.
  • the braking action also acts to prevent backward rotation of the ratchet wheel when the pawl is retracted.
  • the ratchet teeth 1121a have a pitch P, so that stroke of reciprocation of the tooth 1120a, in a direction tangential to the ratchet wheel at the point of engagement of the tooth and the ratchet wheel, should be not less than P and not greater than 2P, for the reasons set forth in full above.
  • the electrical means for oscillating the tines comprise electromechanical driving means capable of converting 15 electrical energy into mechanical energy for oscillating the vibrator, electromechanical sensing means capable of converting mechanical energy into electrical energy and responsive to the oscillation of the vibrator for producing an electrical signal which is a function of the amplitude thereof, and electrical energy supplying means connected in circuit with the driving means and the sensing means for supplying electrical energy to the former in a manner dependent upon or controlled by the electrical signal produced by the latter.
  • Each of these electromechanical means includes a magnetic field producing component and a magnetic field responsive component which is in circuit with the electrical energy supplying means, one of which component is carried by the vibrator for movement therewith during oscillation thereof and the other of which components is carried by the base of the timepiece and cooperates with the one component in such a manner that oscillation of the vibrator is concomitant with the existence of a voltage across the magnetic field responsive component.
  • the magnetic field producing components of the electro-mechanical means are carried by the tines 1103 and 1104, respectively.
  • Each of these magnetic field producing components is constituted by a substantially cup-shaped permanent magnet 1106 which is formed with a rim portion and a central boss portion, the former being shown as constituting an S pole and the latter as constituting a N pole. These portions define an annular space between themselves, as is clearly shown in the drawing.
  • the central boss portion may be omitted and the magnetic characteristics may be imparted to the components 1106 by providing a permanent bar magnet in place of this boss portion so that the components 1106 resemble the magnet field producing means 6, 6a of Fig. 1.
  • One of the magnets 1106 carries an abutment element 1107b the free end of which is spaced a distance s from the other magnet 1106, thus establishing the absolute maximum amplitude at which the tines 1103 and 1104 can oscillate.
  • Each of the magnets 1106 cooperates with a magnet field responsive component which, in the embodiment shown in Fig. 20, is constituted by a coil.
  • the coil associated with one of the magnets 1106 is a sensing coil indicated as Sc and the coil associated with the other magnet 1106 is a driving coil indicated as D which has approximately five to six times as many turns as the sensing coil Sc.
  • Each coil is carried by a stationary tubular carrier 1110 which is fixed to a support 1113, each support in turn being mounted to the base plate of the timep1ece (not shown in Fig. 20).
  • the arrangement of the parts is such that the coils extend into the annular spaces formed by the rim and boss portions of the respective magnets 1106, there being sufiicient clearance between the outer surface of each coil and the inner surface of the rim portion of the corresponding magnet as well as between the inner surface of each tubular carrier 1110 and the outer surface of the boss portion of the corresponding magnet to permit reciprocation of the magnets relative to the coils during oscillation of the tines.
  • oscillation of the tines is concomitant with the existence of a voltage across the coils, the amplitude of oscillation and the amplitude of the voltage being interdependent upon each other.
  • each coil together with its cooperating magnet forms an electro-mechanical transducer.
  • the driving coil D together with its cooperating magnet 1106 forms an electro-rnechanical driving means capable of converting electrical energy into mechanical energy, i.e., a voltage placed across the driving coil D will cause movement of the cooperating magnet and an alternating voltage will cause reciprocation of the magnet and consequently oscillation of time 1104 and; by force, of tine 1103 since it is one of the basic characteristics of a tuning-fork type vibrator that its tines oscillate together.
  • the amplitude of oscillation of the tines will depend upon the amplitude of the voltage placed across the driving coil.
  • the sensing coil Sc together with its cooperating magnet 1106 forms an electro-mechanical sensing means capable of converting mechanical energy into electrical energy, i.e., oscillation of the tine 1104 and reciprocation of the associated magnet 1106 will induce an alternating voltage across the sensing coil Sc, the amplitude of this induced voltage being dependent upon the amplitude of oscillation of the tine 1104.
  • the coils S and D are connected in circuit with the electrical energy supplying means.
  • the latter is responsive to the signal or control voltage induced in the sensing coil and produces a driving voltage across the driving coil which is a function of the amplitude of the signal, the arrangement being such that the control voltage which, by virtue of the fact that the sensing coil has fewer turns than the driving coil, is smaller than the driving voltage, is amplified in such a manner as to maintain the driving voltage constant.
  • the electrical energy supplying means includes a transistor TR having base, emitter and collector electrodes respectively indicated at B, E and C, a battery or other suitable source of voltage B, a capacitor C and a resistor R.
  • the transistor is preferably a germanium junction transistor and the battery is preferably one the terminal voltage of which, throughout substantially the entire useful life of the battery, remains substantially constant, with the voltage decreasing sharply only when the battery is almost completely discharged.
  • the battery may be of the mercury-cell type having a terminal voltage of approximately 1.3 v.
  • the capacitor C having a capacitance of the orderof 2 microfarads and the resistor R having a resistance of the order of 2 megohms are connected in parallel with each other, and the parallel circuit is in series with the sensing coil Sc so as to form a series circuit one terminal of which is connected to the transistor base and the other of which is connected -to the positive terminal of the battery.
  • the negative terminal of the battery is connected to one terminal of the driving coil D and forms another series circuit therewith, the terminals of which are constituted by the opposite terminal of the coil D and by .the positive terminal of the battery, respectively.
  • This last-mentioned terminal of the coil D is connected to the transistor collector, and the transistor emitter is connected to the positive terminal of the battery so as to complete the circuit, as shown in Figs. 20 and 21.
  • the instant circuit difiers from that illustrated in Fig. 7 in that the battery B is in the collector branch instead of the emitter branch it being clear, however, that the mode of operation of either arrangement is almost the same. Circuit on Fig. 7 gives a better starting of the oscillation and a smaller variation of 1 caused by amplitude variation.
  • the additional capacitor in parallel with the driving coil D is not necessary when D and Sc coils are on separated magnets or if the electrical coupling between coils D and Sc is so small that no wild oscillation will come up.
  • the battery may be interposed between .the driving coil D and the collector, in which event one terminal of the driving coil D is connected to the positive terminal of the battery, the negative terminal thereof being connected to the collector.
  • the emitter and the one terminal of the sensing coilcapacitor series circuit are connected to the free terminal of the driving coil.
  • the operation of the electrical means including the sensing means, the driving means and the electrical energy supplying means is as follows:
  • the instantaneous amplitude of oscillation of the tines may be represented 17 where A is the peak amplitude of the tine measured as the center of gravity of the respective permanent magnet 1106, and the rate of travel .or velocity of the magnet may then be expressed by With n d and B representing the number of turns and the diameter of the sensing coil Sc and the flux density of the magnet 1106 associated therewith, and with n d and E representing the number of turns and the diameter of the driving coil D and the flux density of the magnet 1106 associated therewith, the voltages across these coils may be represented as follows:
  • the .above mentioned voltage V is induced thereacross during oscillation of the tines, and the base voltage V may then be expressed as follows:
  • V being the voltage across the capacitor C
  • the latter constituting a DC voltage source which is capable of temporarily retaining a voltage generated by the coil S and the diode base-emitter of the transistor and of supplying this voltage as a negative bias for biasing the transistor in such a manner that the same is in class C operation.
  • the capacitor C may be replaced by a battery or other voltage source for supplying the desired biasing voltage, but the oscillator will not start itself.
  • the alternating voltage V causes the base current I to vary in the manner shown in Fig. 22, and the changing base current, in turn, controls the collector current I in such a manner that its configuration or wave shape may assume that shown in the same figure.
  • the battery B will cause a collector current I to flow through the driving coil D so that the same produces the driving voltage V which is equal to with V representing the battery voltage and V the collector voltage.
  • V representing the battery voltage and V the collector voltage.
  • V being the collector voltage at the instant I is greatest.
  • the construction of the whole circuit is such that so that, inasmuch as the transistor has characteristics analogous to that of a pentode in that the collector current I is very strongly influenced when changes in the collector voltage V occur within the range of 0 to 0.3 v., small changes in the collector voltage brought about by small changes in the voltage V across the driving coil D produce relatively large changes in the collector current I and that alone stabilizes the amplitude.
  • the entire electrical means are thus capable not only of driving the tines, but serve as an automatic regulator for oscillating the tines at a constant amplitude, the significance of which is described above.
  • the variation of V has no stabilizing effect, this voltage only determines the moment, when the current I has to flow which current causes a I current. But the volume of I is determined by the voltage V min. The amplitude stabilizing effect is limited at a current I max. This I: max.
  • the voltage V min. will be greater than 0 3 volts which is about the knee of the pentode characteristic of a junction transistor. Then for V min. greater than 0 3 volts the current I max. is current amplification factor of the transistor multiplied by 1 max. With capacitor-resistor biasing and these two connected on the negative pole of the battery as shown in Fig. 21 the current I, max. is almost independent on variations of V caused by variations of the amplitude. This I, max. must be chosen by calculating the resistor which is parallel to the capacitor in such a manner that the greatest friction which may occur in the timepiece produces a current I which is still smaller than 1 min. as described above. Now the amplitude stabilizing effect, which works only in the region of O to 0 3 volts for V min. is regulating like this:
  • the amplitude of oscillation of the tines is automatically maintained between certain minimum and maximum amplitudes so that the pawl means 1120, 112th: are reciprocated with a stroke the length of which is maintained between certain minimum and maximum lengths.
  • These minimum and maximum amplitudes are the extreme amplitudes of a very narrow range of amplitudes, so that for practical purposes the amplitude of oscillation of the tines is maintained constant at that amplitude at which the base and collector voltages and currents assume the values shown in Fig. 22.
  • this amplitude corresponds to a reciprocation of the pawl means with a stroke the length of which is equal to approximately 1.5P.
  • a separate battery may be substituted for the capacitor C.
  • the capacitor serves to bring about a relatively small change in the base current during relatively large changes in the voltage V due to the automatic bias action.
  • the capacitor resistor-type bias voltage source serves to drive the base voltage positive during at least a portion of the cycle, despite the occurrence of a relatively sharp amplitude decrease.
  • the oscillation would stop because I would be 0.
  • This condition is prevented by providing the biasing capacitor C and resistor R which at all times supplies a negative biasing of such magnitude as to drive the base current positive during a portion of the cycle. In this way, the tines will be returned to normal amplitude oscillation even after a sharp amplitude decrease.
  • the physical arrangement of the sensing and driving coils may differ from that shown in Fig. 1 wherein both coils are associated with a single magnet carried by one tine or in Fig. 20 wherein the coils are associated with different magnets carried by different tines.
  • either the driving coil or the sensing coil or both may constituted by two separate coils which are serially connected to each other, with one of these separate coils being associated with the magnet carried by one of the tines and with the other being associated with the magnet carried by the other tine.
  • the total space available for the sensing and driving coils which, in a timepiece of the character described, may be extremely small-may be utilized to best advantage, i.e., the total physical space requirement of both the sensing and driving coils may be evenly divided between the two magnets.
  • a timepiece having a timepiece mechanism, in combination, a base; ratchet wheel means having ratchet teeth of predetermined pitch and being rotatably carried by said base, said ratchet wheel means being operatively associated with said timepiece mechanism for driving the same at a rate directly proportional to the speed of rotation of said ratchet wheel means; reciprocatable driving means cooperating with said ratchet wheel means for rotating the same when the length of the stroke of reciprocation of said driving means is between a predetermined minimum stroke length which is a function of the pitch of said ratchet teeth and a predetermined absolute maximum stroke length which is a function of twice the pitch of said ratchet teeth; a tuning-fork type vibrator carried by said base and having a pair of tines capable of oscillating at a constant frequency, one of said tines being connected to said driving means for reciprocating the same with a stroke the length of which is a function of the amplitude of oscillation of said tines, each oscillation of said one tine bringing about one
  • said abutment means include at least one abutment element arranged between said tines, carried by one of said tines adapted to engage the other of said tines.
  • said abutment means include a pair of abutment elements ar ranged between said tines and carried by said tines, respectively, said abutment elements being adapted to engage each other.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Electromechanical Clocks (AREA)
  • Oscillators With Electromechanical Resonators (AREA)
  • Electric Clocks (AREA)
US584709A 1955-05-12 1956-05-14 Electrical timepiece Expired - Lifetime US2960817A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH840086X 1955-05-12

Publications (1)

Publication Number Publication Date
US2960817A true US2960817A (en) 1960-11-22

Family

ID=4541157

Family Applications (1)

Application Number Title Priority Date Filing Date
US584709A Expired - Lifetime US2960817A (en) 1955-05-12 1956-05-14 Electrical timepiece

Country Status (7)

Country Link
US (1) US2960817A (enrdf_load_stackoverflow)
CA (1) CA583728A (enrdf_load_stackoverflow)
CH (1) CH342171A (enrdf_load_stackoverflow)
DE (1) DE1095747B (enrdf_load_stackoverflow)
FR (1) FR1153306A (enrdf_load_stackoverflow)
GB (1) GB840086A (enrdf_load_stackoverflow)
IT (1) IT552682A (enrdf_load_stackoverflow)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3079748A (en) * 1960-06-27 1963-03-05 Sylvania Electric Prod Illuminated electronic time piece
US3118383A (en) * 1964-01-21 Electromagnetically actuated device with feedback control
US3132522A (en) * 1960-12-06 1964-05-12 Gen Precision Inc Rotary speed regulator
US3176171A (en) * 1961-03-14 1965-03-30 Suisse De Rech S Horlogeres La Electromagnetic oscillatory drive
US3283495A (en) * 1964-02-18 1966-11-08 Centre Electron Horloger Electronic watch
US3292064A (en) * 1964-03-16 1966-12-13 Gen Electric Frequency regulated chronometer
US3338047A (en) * 1965-10-18 1967-08-29 Gen Time Corp Frequency regulator for tuning fork drive system
US3363197A (en) * 1964-06-03 1968-01-09 Int Standard Electric Corp Circuit arrangement for electric clocks comprising mechanical oscillators
US3417632A (en) * 1966-04-22 1968-12-24 Kienzle Uhrenfabriken Gmbh Device for converting tuning fork vibration to rotary motion
US3546500A (en) * 1968-05-29 1970-12-08 Bulova Watch Co Inc Elastic resonator for timekeeping instruments
US4205451A (en) * 1979-02-12 1980-06-03 Caterpillar Tractor Co. Displacement transducer

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3124730A (en) * 1964-03-10 Thoma
US3118098A (en) * 1957-06-07 1964-01-14 Jahresuhren Fabrik G M B H Oscillating drive electromagnetic motor system
DE1087528B (de) * 1958-01-10 1960-08-18 Reich Robert W Zeithaltendes elektrisches Geraet, insbesondere elektrische Uhr
DE1166101B (de) * 1958-06-14 1964-03-19 Durowe Deutsche Uhren Rohwerke Kontaktlos gesteuerter mechanischer Schwinger als Gangordner eines zeithaltenden Geraets
DE2419432C3 (de) * 1974-04-23 1985-05-09 Papst-Motoren GmbH & Co KG, 7742 St Georgen Kollektorloser Gleichstrommotor mit einem Stator und mit einem permanentmagnetischen Rotor
EP2175999B1 (en) 2007-06-21 2017-01-04 Gen-Probe Incorporated Receptacles for use in performing processes

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR767359A (fr) * 1933-04-10 1934-07-17 Appareil horaire synchrone

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1090564A (fr) * 1953-09-17 1955-03-31 Hatot Leon Ets Perfectionnements apportés aux mécanismes horaires et aux appareils analogues
FR1092411A (fr) * 1953-10-21 1955-04-21 Hatot Leon Ets Perfectionnements aux appareils horaires électromagnétiques

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR767359A (fr) * 1933-04-10 1934-07-17 Appareil horaire synchrone

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3118383A (en) * 1964-01-21 Electromagnetically actuated device with feedback control
US3079748A (en) * 1960-06-27 1963-03-05 Sylvania Electric Prod Illuminated electronic time piece
US3132522A (en) * 1960-12-06 1964-05-12 Gen Precision Inc Rotary speed regulator
US3176171A (en) * 1961-03-14 1965-03-30 Suisse De Rech S Horlogeres La Electromagnetic oscillatory drive
US3283495A (en) * 1964-02-18 1966-11-08 Centre Electron Horloger Electronic watch
US3292064A (en) * 1964-03-16 1966-12-13 Gen Electric Frequency regulated chronometer
US3363197A (en) * 1964-06-03 1968-01-09 Int Standard Electric Corp Circuit arrangement for electric clocks comprising mechanical oscillators
US3338047A (en) * 1965-10-18 1967-08-29 Gen Time Corp Frequency regulator for tuning fork drive system
US3417632A (en) * 1966-04-22 1968-12-24 Kienzle Uhrenfabriken Gmbh Device for converting tuning fork vibration to rotary motion
US3546500A (en) * 1968-05-29 1970-12-08 Bulova Watch Co Inc Elastic resonator for timekeeping instruments
US4205451A (en) * 1979-02-12 1980-06-03 Caterpillar Tractor Co. Displacement transducer

Also Published As

Publication number Publication date
DE1095747B (de) 1960-12-22
FR1153306A (fr) 1958-03-05
CH342171A (de) 1959-10-31
GB840086A (en) 1960-07-06
CA583728A (en) 1959-09-22
IT552682A (enrdf_load_stackoverflow)

Similar Documents

Publication Publication Date Title
US2960817A (en) Electrical timepiece
US2949727A (en) Electric timepiece
US9354607B2 (en) Frequency regulation of a timepiece resonator via action on the active length of a balance spring
US3149274A (en) Electromagnetic vibrating drive
US3057147A (en) Motion converter
US3756014A (en) Synchronized quartz crystal watch
US3616638A (en) Crystal-controlled mechanical resonator
US3176167A (en) Quartz oscillator and drive system
US2929196A (en) Electric timepiece
US3277644A (en) Tuning fork timepiece
US3070951A (en) Frequency-adjustable tuning fork type vibrator for an electrically energized timepiece
US3421309A (en) Unitized tuning fork vibrator
US3192701A (en) Vibratory motion converter for an electric timepiece
US3472020A (en) Electrically powered timepiece
GB1499575A (en) Electronic buzzers
US3167905A (en) Motion transformers for electronically controlled timepiece
US2900786A (en) Timepiece arrangement
US3509437A (en) Timepiece drive
US3184981A (en) Electronically-controlled timepiece and motion transformer therefor
US3377874A (en) Motion converter
US3200270A (en) Electromechanical driving system for time-piece gearing
US3425210A (en) Stepping device for tuning fork oscillator
US3641761A (en) Watch transducer
US3218533A (en) Oscillator controlled electromagnetic drive
US3813871A (en) Clock utilizing a magnetic escapement mechanism