US3462943A

US3462943A - Alarm wristwatch

Info

Publication number: US3462943A
Application number: US615495A
Authority: US
Inventors: Paolo A Spadini; Andre Micheloud
Original assignee: Individual
Current assignee: Individual
Priority date: 1966-02-17
Filing date: 1967-02-13
Publication date: 1969-08-26
Anticipated expiration: 1986-08-26
Also published as: CH537041A; CH896768A4; DE1787018B1; DE1673697B2; CH517332A; DE1673697A1; CH230666A4; GB1172546A; DE1787017A1

Abstract

1,172,546. Alarm watches. P. SPADINI. Feb.17, 1967 [Feb.17, 1966; June 8, 1966; Sept.9, 1966], No.7756/67. Heading G3T. An alarm wrist watch comprises a membrane 17 for generating an audible alarm, a spring blade 18 capable of vibrating at a predetermined natural frequency and positioned to cause the membrane to vibrate, and electrical control means for maintaining the vibration of the spring blade, the electrical control means being actuated by a switch which is operated at a predetermined time by the watch movement. The spring blade 18 is rigidly secured to a post 19 and carries an armature 20 which co-operates with the electrical control means comprising a permanent magnet and coils connected to a conventional battery driven transistorized circuit. An alarm hand is set by rotating a bezel 3 which carries the watch glass 2 and at the pre-set time the alarm sound is transmitted through openings 16 which may be partially or completely closed by a shutter to limit the intensity of the sound. A push button switch is provided in series with the movement actuated switch to enable the alarm to be shut off. The watch case is rectangular but modifications are described for circular watch cases and the alarm sound may be produced by the blade striking a pin attached to the watch glass. In a further modification, the alarm mechanism comprises a timing fork with circular tines, one of which is adapted to strike a bell and a tuning fork with parallel tines may also be used.

Description

Aug 26, 1969 P. A. sPADlNl ETAL ALARM WRISTWATCH 3 Sheets-Sheet l Filed Feb. 13, 1967 EJE. 2

EYE. Z

Aug. 266, 1969 P. A. sPADlNl ETAL ALARM WR I STWATCH I5 Sheets-Sheet 2 Filed Feb. 13, 1967 US- 26, 1969 l P. A. sPADxNl ETAL. 3,462,943

ALARM WRISTWATCH a Filed Feb. 13, 1967 -3 Sheets-Sheet 3 United States Patent O 3,462,943 ALARM WRISTWATCH Paolo A. Spadini, 88 Ave. Leopold-Robert, La Chaux-de- Fonds, Switzerland, and Andre Micheloud, Bern, Switzerland; said Michelond assignor to said Spadini Filed Feb. 13, 1967, Ser. No. 615,495 Clalms priority, application Switzerland, Feb. 17, 1966, 2,306/ 66; June 8, 1966, 8,252/66; Sept. 9, 1966,

Int. Cl. G04b 23/12 U.S. Cl. 58-57.S 16 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION Field of the invention The invention relates to alarm Wristwatches of a particular well known type. The type of alarm Wristwatches referred to here may be specified by three particulars:

(l) The audible sound of the alarm device is produced by a generator provided in the form of a vibrating member;

(2) An actuating device, which is operable by means of a source of energy, is arranged so that it can set the sound generator into vibration;

(3) A releasing mechanism is associated with both said actuating device and the watch movement. This releasing mechanism has a locking position in which it keeps inoperative the actuating device, thus holding the alarm device at rest. As regards the association of the releasing mechanism with the watch movement, it is conceived in such a way that the watch movement may remove the releasing mechanism from its locking position at predetermined hours. As soon as the releasing mechanism has been removed from its locking position, the actuating device becomes operative and consequently the sound generator produces an audible sound.

Description of the prior art The alarm Wristwatches which can be found on the market are provided with a mechanical alarm device. This device usually comprises a hammer provided for striking on the vibrating sound generator. The hammer carries an escapement lever which is actuated by an escape wheel. The source of energy used for -driving the alarm device of these known Watches consists of a spring motor housed in a barrel which is connected to the escape wheel by gear means. The member against which the alarm hammer strikes is either the sound generator itself or a pin secured thereto. In the trst event, the sound generator is usually constituted by a bell secured to the Watchcase bottom While in the second one, it is either the bottom itself or a metallic membrane secured to the caseband and forming part of a double bottom.

Most of these known watches are provided with two control stems, one for Winding up the watch and for setting the hands thereof, and the other one for winding up the alarm device and for setting the time of the alarm. There are also alarm Wristwatches provided with "ice a single control stem. When this stem is in Winding positlon, rotating the same in one direction winds up the watch and rotating the stem in the opposed direction winds up the alarm device. By shifting the stem into different axial positions, one can set the watch hands and the alarm hand.

Alarm Wristwatches comprising a single spring motor for driving both the watch movement and the alarm device are also known in the art. A locking device is provided for preventing this spring motor from dissipating all the energy stored up therein, when the alarm is released. The additional mechanisms which have to be provided 1n the alarm Wristwatches comprising either a single control stem or a single spring motor are quite particular and delicate. Moreover, they do not operate safely. In addition thereto, these mechanisms can hardly be mounted in a standard watch movement which had originally been designed for other purposes, so that a particular watch movement has to be designed and manufactured especially in view of the alarm device which will have to be incorporated therein.

Besides the drawbacks, which are specically due to these particular mechanisms, the known alarm Wristwatches provided with a mechanical alarm device have all the same drawback. Due to the fact that the watch movement has to be provided with a hammer which is able to strike against a member secured to the watchcase bottom, such a mechanical `alarm device can hardly be incorporated with a watch movement provided with a conventional selfwinding device. A conventional selfwinding Watch indeed comprises a Winding weight which is journalled in the center of the movement and which comprises a heavy portion moving all round the movement and this winding weight thus constitutes a barrier between the movement and the Watchcase bottom, which cannot be crossed by any element (pin or stud) fixed to the bottom and against which the hammer could strike. On the other hand, a winding Weight which only oscillates within a sector limited by stops does notoriously not operate in an adequate manner.

Finally, even if the watch movement were wound up automatically by means of a small winding weight mounted in an eccentric position Within the watch movement, the alarm wristwatch equipped with a mechanical alarm device would still have the drawback that it would not be a fully selfwinding watch. Everytime after the alarm device has run down, one would have to wind it up by hand in order to set it again.

As a matter of fact, there are also timepieces in which winding up the spring motor of the alarm device occurs electrically, by means of a motor. The operation of such a motor, however, requires a powerful source of energy. If a motor were provided for winding up the alarm device of a wristwatch, this motor should accordingly be supplied with current from a battery which could not possibly be mounted in the casing of a wristwatch. There are truly also timepieces with an alarm device in which the hammer striking the sound generator is also actuated by a source of electric current, but in a more economic manner. Instead of actuating the hammer mechanically by means of an escape wheel driven by a spring motor and of a lever secured onto the hammer shaft, the hammer is actuated electromagnetically, by means of a fixed coil which is periodically energized and of a permanent magnet fixed onto the hammer shaft.

The hammers of these known alarm devices have, however, a relatively great inertia so that they can only be actuated by a correspondingly powerful source of energy. iIn other words, these known alarm devices have still too small a yield for their efficient accommodation within the sizes of a wristwatch. The required source of energy could not practically be located in the watchcase.

Summing up, among the known alarm devices there is no small one which could be associated with a conventional selfwinding wristwatch and there is neither one which could be associated with a selfwinding `watch movement and simultaneously be reduced to such sizes as to be suitable for the accommodation of all its components within the boundaries of the casing of a wristwatch.

SUMMARY OF THE INVENTION The alarm wristwatch according to the invention is improved by a new alarm device. This alarm device sets the sound generating member into vibration by means of an armature which is arranged for vibrating itself at a natural frequency substantially equal tothat of the audible sound which said sound generating member is intended to produce. Moreover, said armature is kept vibrating at said natural frequency by means of a controlling electromagnetic eld which is supplied by an electric source of energy.

Since the armature of the alarm device according to the invention is arranged so as to vibrate at a natural frequency, keeping this armature vibrating at said frequency does obviously not dissipate a great amount of energy. The alarm device of the alarm wristwatch according to the invention has thus a substantially higher yield than the alarm devices of the known watches. It is therefore possible without any difficulty to actuate said alarm device by means of a battery having the adequate sizes for accommodating the same within the casing of a wristwatch.

The sound generating member can consist of a plastic membrane which is capable to vibrate at different frequencies of the audible spectrum. In a watertight wristwatch the use of another type of sound generating member, for instance of a member which can itself vibrate at a natural frequency, will simplify the construction. With such a sound generating member the armature of the alarm device according to the invention will advantageously cause this sound generating member to vibrate by striking thereon. Said sound generating member can thereby consist of either the watchcase bottom, or a bell secured to this bottom, or a metallic membrane forming part of a double bottom and accordingly having its periphery secured to the caseband. The sound generating member can even consist of the watch glass. To set the same into vibration, the armature of the alarm device can strike for instance against a pin secured to the glass and extending through a dial opening.

As regards the armature itself of the alarm device according to the invention, it can either be carried by a spring blade having one end rigidly fixed to a support, or consist of such a spring blade, or even consist of one branch of a tuning fork.

In addition to the fact that entertaining the vibration of a tuning fork at its natural frequency ensures a very high yield, and to the fact that using a tuning fork for striking on a membrane or a bell only dissipates small amounts of energy, the tuning fork has still a particular advantage. It can be made in a shape which will be particularly suitable for accommodating the same within the casing of a wristwatch. A tuning fork can indeed be made with a shape similar t`o that of the watch movement so that it `will be possible to locate the same within the annular space which is usually comprised between the watch movement and the casing. However, the tuning fork can of course also be made with parallel branches and be mounted within the `watch movement itself, for instance at the place provided in the conventional movements for locating the mechanical alarm devices used heretofore.

to the invention are represented diagrammatically and by way of example in the drawing in which:

FIG. l is a plan view of the first embodiment;

FIG. 2 is a view similar to that of FIG. 1, the casing being open and some parts having been removed;

FIG. 3 is a part sectional view on a larger scale along line III-III of FIG. 1;

FIG. 4 is a diagram of the electrical connections included by the alarm device of the watch;

FIG. 5 is a plan view of the second embodiment;

FIG. 6 is an elevational view with some parts in section of the third embodiment;

FIG. 7 is a partial plan view of this third embodiment, and

FIG. 8 is a plan view of the fourth embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The watch represented in FIGS. 1 through 4 is a rectangular wristwatch. It is provided with a circular watch movement (not shown) which comprises a selfwinding mechanism of conventional type. To release the alarm device, this 4watch movement comprises a cam and a movable contact member cooperating with said cam, both being mounted onto the motion work of the movement coaxially thereto, substantially as disclosed in the Swiss Patent No. 371,750. Like in that patent, the alarm hand 1 can be set by rotating the glass 2 which is carried by a rotatory Ibezel 3. The watch movement is located in a lodging 4 of a frame member 5 which is furthermore provided with the additional lodgings 6, 7 and 8 for the accommodation of the different units of the alarm device. The frame member 5 has an outer shape matching with the side wall of a watchcase piece 9 which constitutes both the watchcase bottom and the case band and which carries the lugs 10 to which the Wristband 11 is attached. A conventional crown 12 enables both manually winding up the watch movement and setting the watch hands 13.

A cover member 14 is removably secured to piece 9 and closes the watchcase. The cover member 14 carries an annular projection 1S serving as journalling means for the rotatory bezel 3. Cover member 14 is provided with a series of openings 16 in order to ensure the passage of the sound produced by the alarm device as described hereinafter. Dust is, however, prevented from entering the watchcase by means of a membrane 17 which is secured to the cover member 14 under the openings 16.

The membrane 17 constitutes the sound generating member of a sound generator of the type disclosed in Swiss `Patent No. 409,715. Membrane 17 can be set into vibration by means of a spring blade 18, which is rigidly secured at one end to a stud 19 xed itself to cover member 14. For this purpose the spring blade 18 carries an armature 20 which extends over a permanent magnet being in the form of a magnetic sleeve 21. A stimulating coil and a motor coil (not shown) are mounted within sleeve 21. These two coils are connected to a transistorized well known control circuit (not shown), which is supplied by a battery 22 lying in lodging 8 of frame member 5. The stimulating coil is sensitive to the variations of the magnetic flux between sleeve 21 and armature 20, which occur when blade 18 vibrates. This stimulating coil biases then the control circuit periodically at a frequency equal to the natural frequency of blade 18 and in such manner that the motor coil gives entertaining impulses to blade 18 through armature 20 at moments which have the adequate difference of .phase in order to produce a phenomenon of resonance and to entertain in that way a strong vibration of blade 18. In the absence of membrane 17, blade 18 would vibrate at a relatively low natural basis frequency. Membrane 17, which has a pyramidally shaped central portion is, however, located in the vicinity of blade 18 so that the apex of the pyramidal portion of membrane 17 lies opposite a predetermined point of blade 18. This point is calculated according to the theory of vibrations in such manner that blade 18 will not transmit its basis vibration to membrane 17 but a good audible harmonic thereof, which has a substantially higher frequency. For that purpose the apex of the pyramidal portion of membrane 17 can always remain in contact with blade 18, for instance by means of a rigid connection such as provided by welding, gluing, riveting, or simply by pressure. Similar results can, however, also be obtained if blade 18 strikes against the apex of membrane 17. By vibrating over lodging 7, which operates as a sound box, membrane 17 generates a relatively pure sound Awhich is perfectly audible.

Tests have shown that a membrane having an area of about 150 mm.2 can be kept vibrating by a current of 5 ma. at a frequency of 4000 cycles per second and produce a sound having still an intensity of 70 to 80 phon at a distance of 30 cm. With a source of energy constituted by one of the smallest available batteries, it has been possible to hold the alarm device 4of the watch described ringing uninterruptedly during 45 hours.

A pushbutton 23 actuates a switch 24 located in lodging 6 of frame member 5 and permits stopping the alarm device from outside the casing at any desired moment.

The different units of the alarm device are electrically connected as shown in FIG. 4. The sound generator 25 comprising blade 18 and membrane 17 is connected in the circuit supplied by battery 22 in series with switch 24 and a contact 26. Contact 26 is actuated by cam 27 of the releasing mechanism of the alarm device, which is mounted coaxially to the motion work of the watch as indicated hereabove.

In the manufacture of the watch represented in FIGS. l through 4 any available conventional watch movement either circular or of another shape can be used. The releasing mechanism of the alarm device need only be mounted thereon.

Since the alarm device of the watch described produces a relatively pure sound, the intensity of that sound can easily be varied at vwill within broad limits. For that purpose, a shiftable shutter provided under openings 16 for closing these openings to a more or less great extent, constitutes a suitable means. If the alarm device has to be set so that it will be released at a time at which the Watch carrier is for instance in conference, the openings 16 can be closed and the sound intensity accordingly reduced to such an extent that only the watch carrier will be able to hear the alarm device of his watch.

In order to avoid that foreign particles fall onto membrane 17 through openings 16 and gradually prevent that membrane from vibrating properly, a sheet of soft material could be stretched under openings 16.

Since membrane 17 can anyway be tightly fixed to cover member 14, the casing of the wristwatch described can be made watertight without any difculty.

The second embodiment (FIG. 5) is constituted by an alarm wristwatch having a circular shape. This watch comprises `a watch movement 28 similar to that of the first embodiment. The different units constituting the alarm device (battery 22a, magnetic sleeve 21a, blade 18a, printed circuit 29 controlling the coils which actuate the sound generating member) are located around the watch movement 28, within lodgings provided in an enlargement and engaging ring of the watch movement. In this embodiment the watchcase opening for the sound of the alarm device is advantageously provided in the bottom of casing 30. Like in the first embodiment, the membrane constituting the sound generating member can be secured to the watchcase bottom so Vas to provide for a tight closure of this casing. The watch of this embodiment can be provided with `a conventional dial which extends over the whole visible surface of the watch. Hands 1a and 13a having sizes matching with those of the dial can also be provided.

Like in the first embodiment, the movement 28 can be wound up and the hands 13a can be set by means of a conventional crown 12, whereas the alarm hand 1a can be set by means of .a rotatory bezel 3a.

The manufacture of a watertight alarm wristwatch can, however, be performed easier as shown by the third embodiment (FIGS. 6 and 7).

In this embodiment the watchcase has again a rectangular or square shape and the glass 31 comprises a peripheral flange 32, which is clamped in axial direction between the upper edge of a piece 33 and an inwards projecting ange of a piece 34. Piece 33 constitutes the watchcase bottom and it comprises an upright wall surrounding the space provided for the watch movement. Piece 34 is secured in a known manner to piece 33 and it constitutes both the bezel .and the case band of the watchcase.

The alarm device of this watch also comprises -a magnetic sleeve 35. This sleeve is fixed to a bracket 36 which is located in an opening provided in a frame member. Instead of positioning sleeve 35 so that its axis is parallel to that of the watch, like in the two first embodiments, sleeve 35 is here, however, lying. A spring blade 37 carrying an armature or constituting itself an armature has one end rigidly secured to bracket 36 by means of a rivet 38. The actuating means provided for setting blade 37 into vibration are similar to those used in the two first ernbodiments.

The watch represented in FIGS. 6 and 7 still comprises a member connecting blade 37 to glass 31 in order to transmit the vibration 'of blade 37 to the glass, which constitutes the sound generating member of this embodiment. This connecting member consists of a pin 39 having one end embedded in a projection 40 of the glass. Pin 39 extends through an opening 41 of dial 42 so that its free end lies in the immediate vicinity of blade 37.

The vibration of blade 37 is transmitted to the glass 31 through pin 39 preferably by striking. The glass produces thus an audible sound as long as its vibration is entertained by the coils located in sleeve 35, which bias the controlling electromagnetic field.

Blade 37 carries a stud 43 which butts against a rigid part carried by bracket 36, when blade 37 is vibrating. As a consequence thereof, the basis vibration of blade 37 has a wav-e length which is not four times, but only twice as long as blade 37. Moreover, the striking point of blade 37 against pin 39 is chosen in such manner along blade 37, that the same vibrates at a natural frequency which is a harmonic of its basis frequency.

Pin 39 can be hidden by means of an ornamental design provided either on the dial 42 or on a part of the lower surface of glass 31.

The watch of the fourth embodiment (FIG. 8) comprises a circular casing 51 and a circular movement 52 which has a diameter somewhat smaller than that of lodging 53 of casing 51. A tuning fork 54 having the shape of .an open ring, is secured to movement 52 by means of a strap 55 which separates the two branches of the tuning fork from each other.

The vibration of tuning fork 54 is entertained in the same manner as that of the blades described in the three first embodiments, namely by means of an electric control circuit comprising two coils 56, a stimulating and a rnotor coil, which are carried by one branch of tuning fork 54 and which are connected in the input and in the output circuit, respectively, of a transistorized amplifier (not shown). Coils 56 cooperate with a permanent magnet 57 carried -by the other branch of the tuning fork. The electrical control circuit of tuning fork 54 furthermore comprises a first switch (not shown), which is mounted on the hour wheel of the watch and a second manually operable switch for stopping the alarm at will. This second switch can be controlled from outside the casing by means of a pusher (not shown) carried by casing 51.

When tuning fork 54 vibrates, a finger 58 carried by one of its branches strikes against the bell 59 which is secured to the watchcase bottom in a manner Well known to those skilled in the art. One 'branch of the tuning fork could also strike against a pin or a stud carried either by the watchcase bottom or by a metallic membrane constituting a double bottom of the watchcase.

The vibration of tuning fork 54 can be entertained with a substantially smaller dissipation of energy than the usual alarm hammer of the known alarm watches. The small batteries, which are available on the market and which are used in the known electric Wristwatches provided either with a driving balance-wheel or with a regulating and driving tuning fork, can operate the alarm device of the watch represented in FIG. 8 at least during a year, if the alarm is used on an average during five minutes every day.

In a shaped watch provided with a shaped movement the tuning fork used as alarm hammer could also be made in a shape similar to those of the watchcase and the movement, so that the tuning fork could be arranged around this movement. The tuning fork could, however, also be made with two parallel branches and be located at the side of the movement. Finally, the tuning fork could also be shaped so that it could be mounted in the movement itself, for instance at a place which would originally have been provided for a conventional mechanical alarm device.

Although different embodiments of the alarm wristwatch according to the invention have been described in detail hereabove, it should be understood that various changes in the shape, sizes and arrangement of parts will appear obvious to those skilled in the art.

What is claimed is:

1. An acoustical alarm device comprising mechanical sound generating means, a resilient member having a natural frequency, and transstorized electromagnetical means arranged for causing said resilient member to vibrate at said natural frequency as soon as the transistorized electromagnetical means are energized and for entertaining the vibration of said resilient member at said natural frequency as long as said transistor-ized electromagnetical means remain energized, said resilient member being mechanically coupled to said mechanical sound generating means for transmitting its vibration thereto.

2. The alarm device of claim 1, in which the mechanical sound generating means consists of a vibrating member, said resilient member setting said vibrating member into vibration by striking thereagainst.

3. The alarm device of claim 1, in which a spring blade having one end rigidly anchored forms part of said resilient member.

4. The alarm device of claim 1, in which a spring member is constituted by a branch of a tuning fork.

5. The alarm device of claim 1, in which said electromagnetical means comprises an electrical amplier supplied by an electric source of energy, said resilient member reacting on said amplifier and causing the same to entertain the vibration of the resilient member at said natural frequency.

6. The alarm device of claim 5, in which said electrical amplifier comprises an input circuit including a stimulating coil sensitive to the vibration of said resilient member at its natural frequency and an output circuit including a motor coil imparting impulses t said resilient member for entertaining its vibration at said natural frequency.

7. The alarm device of claim 6, in which said resilient member is constituted by a tuning fork, one branch of said tuning fork carrying said stimulating and said motor coil, and the other branch of said tuning fork carrying a permanent magnet cooperating with said coils.

8. An alarm wristwatch comprising a lirst member capable of generating an audible alarm sound by vibrating, a second member capable of vibrating at a predetermined natural frequency ranging within the audible spectrum and being mechanically coupled to said first member for transmitting its vibration thereto, thus generating an audible alarm sound as soon as said second member vibrates, and electrical control means arranged for entertaining the vibration of `said second member at said predetermined natural frequency upon energization of said electrical control means, said electrical control means including a switch being normally open and interrupting the energization of said electrical control means, said switch being set under the control of the watch movement for being closed thereby at predetermined hours.

9. The wristwatch of claim 8, in which said first member includes the watchcase bottom.

10. The wristwatch of claim 8, in which said rst member includes a metallic membrane having its periphery anchored to the case band and forming part of a double bottom.

11. The wristwatch of claim 8, in which said first member includes the watch glass, a pin being fixed to said glass and extending through a dial opening, `and said second member striking against said pin.

12. The wristwatch of claim 8, in which a tuning fork forms part of said second member, said tuning fork having a shape similar to that of the watch movement and being located in an annular space provided around the watch movement, between the same and the watchcase.

13. The wristwatch of claim 8, in which a tuning fork forms part of said second member, said tuning fork being mounted within the watch movement.

14. The wristwatch of claim 8, in which said first member includes a plastic membrane capable of vibrating at different frequencies of the audible spectrum.

15. The wristwatch of claim 14, in which the casing thereof is provided with an opening, said membrane having its periphery tightly secured to a watchcase portion surrounding said opening so as to obture the latter.

16. The wristwatch of claim 14, in which said second member permanently remains in Contact with said rst member and vibrates in unison therewith, when said electrical control means are energized.

References Cited UNITED STATES PATENTS 1,529,852 3/1925 Tanglin 58-57.5 2,435,996 2/1948 Baird. 2,867,795 l/1959 Longton et al. 340-261 X FOREIGN PATENTS 375,664 11/ 1963 Switzerland.

RICHARD B. WILKINSON, Primary Examiner G. H. MILLER, JR., Assistant Examiner U.S. Cl. 340-261