US2588884A - Alarm timepiece - Google Patents

Description

0. M. SCHAFER March 11, 1952 ALARM TIMEPIECE 2 SHEETSSHEET 1 Filed NOV. 18, 1948 m R.F WM M w L. O

March 11, 1952 o. M. SCHAFER ALARM TIMEPIECE 2 SHEETS-SHEET 2 iled NOV. 18, 1948 INVEN TOR.

A TTOR/Vf Y OL/VER M. SCHAFER BY Patented Mar. 11, 1952 UNITED STATES PATENT OFFICE ALARM TIMEIIECE Oliver M. Schafcr, Trenton, N. J. Application November 18, 1948, Serial No. 60,886

2 Claims.

This application is a continuation-in-part of my co-pendin'g application Serial No. 555,531 filed September 23, 1944. now abandoned.

My invention relates to time-pieces embodying an alarm and particularly to constructions adapted for use by those who are hard of hearing, whereby a physical sensation may be given to the user for alarm purposes.

It is well known that many persons cannot hear the usual audible alarms of alarm clocks and alarm watches because of deafness or because they sleep too soundly. Others find it annoying to be startled from sleep by a sudden loud noise and such alarms frequently awaken children or persons other than those whom it is intended to notify.

Efforts to overcome these limitations and objections to audible alarms have given rise to watches or clocks with alarm elements such as a member for pricking the skin or other signals which are uncomfortable or objectionable and quite as startling in their effect as an audible alarm. Other constructions are electrically actuated and therefore have to be connected to a house lighting circuit or provided with batteries so that they include wiring or are expensive, bulky and complicated in construction.

In accordance with my invention these objections to prior types of alarm time-pieces are overcome and constructions provided in which the alarm means serves to impart a mild but positive physical sensation to the user, which may be in the nature of a rubbing, reciprocating tapping or other light motion or a combination of such motions which will awaken a person without shock and without disturbing others. The alarm means may be embodied in a case with the usual timing mechanism or may be applied to existing watches by simple replacement or adaptation of elements.

One of the objects of my invention is to provide novel alarm time-pieces adapted for use by those who are hard of hearing and which will not disturb others.

Another object of my invention is, to provide an alarm watch or time-piece which will serve to impart a mild physical sensation to the users body. v

A further object of my invention is to provide an alarm mechanism which may be applied to or used with conventional watches or timing mechanism for actuation thereby.

These and other objects and features of my invention will appear from the following description thereof in which reference is made to the figures of the accompanying drawing.

In the drawing:

Fig. l is an enlarged view partly in vertical section and partly in elevation showing a typical construction embodying my invention;

Fig. 2 is a plan view of the construction shown in Fig. l with a portion of the case for the alarm mechanism broken away;

Figs. 3 and 4 are sectional views of portions of the construction shown in Fig. 1 illustrating details of the device;

Fig. 5 is a vertical sectional view through an alternative alarm watch construction embodymg my invention;

Fig. 6 is a top plan view of a portion of the construction shown in Fig. 5;

Fig. 7 is an enlarged view of a detail of the construction shown in Fig. 5;

Fig. 8 is a vertical sectional view through a portion of a watch illustrating a further alternative embodiment of my invention;

Fig. 9 is an enlarged view partly in section showing a detail of the construction illustrated in Fig. 8; and

Fig. 10 is a perspective of the form of escapement for the alarm mechanism of the construction of Fig. 3.

In that form of my invention chosen for purposes of illustration in Figs. 1 to 4 of the drawing, the invention is designed to be applied as an attachment to a conventional watch such as a wrist watch. The watch is shown as having a case 2 provided with alarm mechanism indicated generally at 4 and adapted to be secured to the rear of the watch case or attached to the conventional rear cover. The upper face of the construction, as seen in Fig. 1, is designed to be placed in contact with the users body and against the wrist, leg, arm or other part of the body, and is held in place by any suitable means such as the strap 6.

The alarm mechanism embodies a stationary housing formed with an inner plate 3 and a marginal flange H1. The housing is adapted to be secured to a conventional watch case so as to replace the outer rear cover thereof and as shown is secured to the inner rear cover 12 of the watch by means of screws It. Any other preferred form of attaching means for securing the alarm mechanism and the housing therefor to the watch may be used as desired.

In order to control the alarm mechanism by operation of the timing mechanism of an existing watch, a gear plate [5 is secured to the top plate [6 of the timing mechanism and carries a cam shaft H to which wheel I8 is secured. A pinion l9 meshes with wheel I8 and is fixed to wheel 20 engaging the pinion 2| concentric with the cam shaft [1. The pinion 2| is fixed to a thimble 22 which is formed on its upper face with a bearing for the cam shaft l1 and formed on its lower face with an extension 23 keyed to the upper end of the shaft 24 of the cannon pinion of the timing mechanism.

In applying such connecting or adapting means to a watch movement, it is of course necessary to drill the top plate l6 to receive thefattaching screws for gear plate [5 and the shaft of pinion IS The hole in plate l6 receiving the upper end of the cannon pinion is enlarged to receive the thimble 22 and the shaft of the cannon pinion is flattened on one or more sides to fit into and establish a driving connection with the thimble 22. The cam shaft I1 is thus driven at a predetermined speed which preferably is the same as the speed of the hour wheel and hand of the watch.

The cam shaft 11 is thus moved by the timing elements of the watch and serves to rotate a timing cam 25 secured to the upper end of the shaft H. The central openings in the inner plate 8 of the housing and in the inner watch cover 12 are preferably of such size that the housing and watch cover can be swung open to expose the timing elements without removing the timing cam 25 from the cam shaft after it has once been secured in place. The cam 25 is also formed with a bevelled marginal edge to permit ready engagement and disengagement of the cam following pivot pin 64 of the alarm with the cam connected to the timing mechanism when the housing [8 is moved with respect to the watch cover. In this way the alarm mechanism may be moved as a unit and swung open or removed from the watch casing to render the timing elements of the watch available for cleaning, adjustment, or repair.

The marginal flange ID of the stationary housing for the alarm mechanism is provided with tapered screws 26 which project inwardly into the annular groove 21 in the downwardly turned outer marginal flange 28 of a rotatable alarm member 30. The alarm member is thus held in place for rotation on the stationary housing and presents an exposed surface 32 which is adapted to be held in contact with the users body by the strap 6 attached to the watch case 2. The surface 32 of the alarm member may be embossed or otherwise formed with mean for imparting a mild rubbing, vibrating or other sensation to the users body upon movement of the alarm memher. As shown, the exposed face of the alarm member is formed with inclined ribs 34 which, upon rotation of the alarm member, serve to rub or knead the users body gently back and forth so as to awaken the user without shock and without disturbing others for whom the alarm is not intended.

Any suitable mechanism may be provided for rotating or otherwise moving the alarm member 38, but in the construction shown, a spring 36 is enclosed within the space between the plate 8 of the stationary housing and the surface 32 of flange 28 of the alarm member. The spring 36 is secured at one end to the flange 28 of the alarm member by a rivet or other fastening means 38, whereas the opposite end of the spring is secured at 40 to a stationary web 42 mounted upon the inner plate 8 of the housing.

The inner edge of the alarm member 30 is formed with a downwardly turned annular flange 44 in which teeth are formed. Alternate teeth 48 of the flange are struck outwardly whereas the intervening teeth 48 are struck inwardly. A suitable number of projections or lugs 58 are extended downward from the flange 44 and serve to support the inner annular edge of the alarm member. The lugs 58 engage the upper surface of a disc 52 which extends over the timing cam 25.

The outwardly projecting teeth 46 on the inner flange 84 of the alarm member are engageable by an escapement member 54 which rocks about a pivot 56 mounted on a spring arm 58 secured to the inner face of the stationary web 42 on the inner plate 8 of the housing for the alarm mechanism. The escapement member is provided with an arm 58 to which a weight 60 is attached. The escapement thus serves to limit or control the speed at which the alarm member 30 is rotated by the spring 36 when the alarm member is released for operation. Furthermore, the weight 60 may be arranged to engage the web 42 of the housing so that on oscillation of the escapement member the weight will strike against and vibrate the housing and give a further alarm effect.

The teeth 48 which extend inwardly from the inner annular flange 44 of the alarm member are positioned to be engaged by a dog 62 pivotally mounted on pivot pin 64 carried by an arm 66. The arm 66 is mounted for movement about the point 68 on the disc 52 and is urged inward by means of the spring 18. The outer end of spring I0 also engages the inner edge of the dog 62 and urges it toward a stop 12 on the arm 66 so as to hold the dog into a projecting position but permit it to be moved in a counter-clockwise direction as seen in Fig. 2 and allow the teeth 48 to pass by the dog when the alarm member is rotated in a counter-clockwise direction to wind the alarm mechanism.

The pivot pin 64, about which the dog 62 is pivotally movable, is extended downward below the arm 66 into position to engage the timing cam 25 and serves as a cam follower adapted to enter the recess 14 in the edge of the timing cam as it rotates with the hour shaft of the timing elements of the watch. The timing cam serves to hold the dog 62 in engagement with the teeth 48 on the alarm member 38 and to prevent rotation of the alarm member until the hour shaft of the watch has reached a predetermined, point corresponding to the time at which the alarm is set to be actuated. When the cam 25has moved to bring the recess 14 adjacent the pin 64 the spring 18 will swing the arm 66 inward and withdraw the dog 62 from teeth 48 so that the alarm member may be rotated or otherwise moved by spring 36.

The disc 52 upon which the arm 66 is mounted is provided with a downwardly turned marginal flange 16 which extends about an annular web 18 carried by the inner plate 8 of the stationary housing. A holding member is arranged to engage the flange 16 on the disc 52 to prevent rotation of the disc and dog 62 by the spring 36. As shown the holding member is in the form of a pin carried by the arm 82 secured to a push rod 84. The rod 84 is urged to the right, as seen in Fig. l, by means of a spring 86 to bring the pin into engagement with one of the notches 88 in the edge of the flange 16. The outer end 90 of the rod 84 projects from the outer marginal flange H] of the housing for the alarm mechanism and may be depressed to disengage the notches in flange 16 when the disc 52 is rotated in setting the alarm mechanism for operation at a predetermined time.

The central portion of the disc 52 is provided with an upwardly projecting cone 92 to which is secured a cover member 94. The cover member lies substantially flush or slightly below the other face 32 of the alarm member 35 and is formed with ribs or depressions 95 by which the cover may be grasped or engaged by the finger to rotate the cover and move the arm 66 and dog 62 with respect to the timing cam 25. In this way the mechanism may be set for operation at a predetermined time. For this purpose also the cover member 94 is provided with numerals 55 which cooperate with the stationary index 93 carried by the outer flange II) of the stationary housing for setting the alarm mechanism as desired. Since the numerals 33 are spaced from the index 93 radially extending lines I03 may be provided on the movable alarm member to aid in positioning the cover member when setting the alarm mechanism for operation at an exact time.

In setting the alarm member the push rod 54 is depressed to cause the pin 80 to be withdrawn from the notches 8B in the flange of disc 52. The cover 32 is thus freed to turn and rotate the disc 52 and dog 62 to the desired position for causing the alarm to operate at a predetermined time. The push rod 84 is then released so that pin 80 will enter the notch in the flange of the disc 52 and hold the disc against rotation. It is important in this connection to locate the notches 88 close together so that a very small rotation of the disc will bring a notch into po sition to be engaged by the pin 80. The pivot pin 64 which serves as a cam follower is thus positioned in a predetermined location with respect to the timing cam 25 to cause the alarm to be actuated at the desired time due to rotation of cam 25 with the hour hand of the watch.

In winding the mechanism preparatory to operation, the user presses the fingers against the ribs 34 of the face 32 of the alarm member 35 and rotates the alarm member in a counter-clockwise direction as seen in Fig. 2. During such movement the dog 62 rocks in a counter-clockwise direction about the pivot pin 64 allowing the teeth 43 to move past the dog. The pin I2 carried by the arm 68 limits movement of the dog 62 in a clockwise direction so that when the mechanism has been suitably wound the dog will remain in engagement with the teeth 48 and prevent the mechanism from becoming unwound until released by the timing cam 25.

Subsequently, when the timing cam 25 has rotated to a position in which the recess I4 is beneath the pivot pin or follower 64, the spring "III will urge the arm 56 inward and thus withdraw the dog 62 from engagement with the teeth 48 of the alarm member. Upon such release of the alarm mechanism the spring 35 causes the alarm member 35 to rotate at a speed controlled by the escapement member 54. As the alarm member moves the ribs 34 on the face 32 of the alarm member adjacent the body of the wearer are caused to rub against the skin and impart a mild rubbing, kneading or other physical sensation which will serve to awaken the user by the unusual but silent and painless action thereof.

When it is desired to stop operation of the alarm mechanism, it is only necessary to rotate the cover member 94 and thus cause the dog 62 to be moved outward into engagement with the inwardly projecting teeth 48 carried by the alarm member.

In order to provide a further and somewhat: more positive alarm for the user, the alarm member 33 may be provided with a slot IE2 and an irregularly shaped disc or member I 54 is rotatably mounted on the shaft I06 secured to the inner surface of the face 32 of the alarm member as shown in Fig. 3. The projections I53 on the member extend through the slot I52 and will press lightly against the users body so that the movement of the alarm member will cause the irregular member I54 to be rotated bringing each of the projections thereof in turn into engagement with the wearer. In this way the wearer is subjected to a light and repeatedly applied pressure which is unusual and therefore serves to attract the attention of the user and will awaken him without a shock.

Fig. 4 illustrates a further and alternative construction which may be used to impart a vibratory or irregular motion to the alarm member. In this construction the annular groove 2'! in the outer flange 28' of the alarm member is formed with a series of curved sections or irregularities I I5 so that on rotation of the alarm member the screws which are carried by the outer flange iii of the stationary housing and which extend into the groove 27, will cause the alarm member to move upand down slightly or to have a vibratory, tapping or other irregular motion which will increase the effectiveness of the alarm.

In that form of my invention illustrated in Figs. 5, 6 and 7 of the drawings, the alarm mechanism is embodied in a watch assembly and as shown the watch has a case I25 with face cover including a rotatable bezel I22 which carries the watch crystal I 24. The bezel and crystal are secured to the face cover by means of the interengaging marginal elements I26. The alarm mechanism is carried by the rear cover member I28 of the watch and includes a rotatable central plate I30 held in place at its periphery by the interengaging portions of the plate and bezel I32. The plate I30 is rotatable about a central screw I34 which is fixedly mounted on the top plate I36 of the watch mechanism.

The watch is provided with an hour hand I38 carried by the central hour shaft I40 and is provided with a minute hand I42 carried by the tubular minute shaft I44 which surrounds the hour shaft I43. An alarm setting hand I 45 is mounted for rotation about the shaft I40 and is located in a plane between those in which the minute and hour hands rotate. The alarm setting hand is movable to any desired position by a lug I48 which is carried by the front bezel I22 and extends inwardly into position to engage the outer end of the alarm setting hand. The latter hand may be moved to any position for setting the alarm by rotating the upper bezel I22 to turn the hand I45 to the desired time indicated on the dial I53 of the watch.

The hour hand and minute hand may be retated by any suitable type of timing mechanism but as shown the mechanism includes a main spring enclosed within the cover I52 which is provided with external gear teeth I5 engaging the pinion I56 on the tubular minute shaft I44. The minute shaft in turn carries a pinion I53 which engages wheel I having an elongated pinion I62 secured thereto. The latter pinion en gages the Wheel I64 attached to the hour shaft I 35 for rotating the hour hand. Conventional winding and setting means may be employed including the crown I66 and winding stem I68 and conventional escapement means (not shown) may be used.

The alarm mechanism including the rotatable plate I30 is actuated by a spring I which surrounds the fixed screw I34 and is enclosed by the drum I12. One end of the spring is secured to the inner face of the drum as indicated at I14 while the opposite end of the spring is secured to the fixed screw I34 as indicated at I16. The drum I12 is'provided with projecting teeth I18 which are engageable by a detent I80 which as shown in Fig. 6 is provided with an inclined face I82 positioned so that when the spring I10 of the alarm mechanism is wound by rotating the plate I30, the teeth I18 on drum I12 will engage the inclined face I82 of the detent to cam the detent outward and ride over it. The detent I80 is urged inward to engage teeth I18 by a spring I84 so that as a tooth I18 passes the detent it will return to a position in which the detent will prevent rotation of the drum in the opposite direction. The spring for the alarm mechanism may therefore be wound so as to place it under tension and maintain the alarm mechanism ready for operation when the spring pressed detent I80 is withdrawn from engagement with one of the teeth I18. A retarding or escapement means I86 of any suitable or preferred type such as that shown at 54 in Fig. 2 is provided for limting the speed of rotation of the drum I12 and plate I30 when the detent is withdrawn.

The spring pressed detent I80 is shown as being in reality the upturned end of a lever I90 which is pivotally mounted at I82. The opposite end of lever I90 is formed with a fork or collar I94 which extends about the reduced end I96 of the hour shaft I40. The hour shaft is movable axially within the tubular minute shaft I44 to rock the lever I90 about its pivot I92. For this purpose a relatively strong leaf spring I88 bears against the end of tubular shaft I44 and the lower surface of wheel I64 on shaft I40 to urge the latter shaft upward as seen in Fig. 5. When shaft I40 is raised by spring I88 and against the action of spring I84, the detent I80 is withdrawn from the path of movement of teeth I18 and against the action of spring I84 so that the alarm mechanism is released for operation.

The time of movement of the shaft I40 is determined by the setting of the alarm setting hand and the movement of the hour hand. For this purpose the hour hand is provided with an inturned and inclined lug I98 as shown in Fig. '1. This lug engages and rides over the annular surface 200 on the alarm setting hand as shown in Fig. 5. A recess 202 is formed in the surface 280 in radial alignment with the alarm hand so that when the hour hand moves into a position overlying the alarm hand, the lug I98 on the hour hand will move into position to drop into recess 202. The spring I88 thus causes the hour shaft to move upward whereupon the lever I90 rocks to withdraw detent I80 from engagement with the teeth I18 on the alarm drum I12. In this way the alarm mechanism is released for operation so that the plate I38 will rotate under the action of the alarm spring I10 and escapement means I85. The alarm may be turned off by simply roiating the upper bezel I22 to move the alarm hand I46 away from the hour hand I38. At such time the inclined form of lug I98 allows the hour hand to turn so that the lug acts as a cam which engages the edge of the recess 202 and moves hour hand and the hour shaft axially against the action of spring I88 to return the hour shaft to its nor-- mal operating position as shown in Fig. 5. As the hour shaft is thus moved the lever I90 is rocked in a clockwise direction by its spring to cause the detent I to engage one of the teeth I18 on the drum I12 to stop the rotation of the plate I30 of the alarm mechanism.

The plate I30 may b suitably formed with projections or other alarm means similar to those described in connection with that form of my invention shown in Figs. 1 to 4. In this way a silent but effective alarm is provided which is capable of awakening or notifying persons who are hard of hearing or others who may wish to be awakened or notified without disturbing anyone else.

The construction shown in Figs. 5, 6 and 7 is unusual in that the minute shaft is in th form of a tubular element supporting the central hour shaft. This renders it possible to actuate the alarm mechanism by use of a single elongated pinion in the timing mechanism. Moreover the dial train which includes the elongated pinion is located adjacent the top plate of the timing mechanism in position to be readily accessible for adjustment or repair of the elements which actuate the alarm mechanism.

A more conventional type of movement is illustrated in Fig. 8 of the drawing wherein the central shaft 2I0 carries the minute hand 2I2 and the minute hand is located above the hour hand 2I4 on the face of the watch. The hour hand is carried by the sleeve 2I6 which is secured to the wheel 2I8 of the dial train. An arouate spring 220 is located between the wheel 2I8 and the bottom plate 222 of the timing mechanism so as to urge the wheel 2 I 8 and sleeve 2 I 6 forward on operation of the alarm. The inner end of sleeve 2I6 normally engages the shoulder 223 on the minute shaft 2I0 whereas the outer end of sleeve 2I6 is in engagement with the inner surface of a central annular extension 224 on the minute hand. Therefore when the sleeve 2I6 is moved forward by sprin 220 it serves to move the minute shaft 2") forward to actuate the alarm mechanism whereas when the hour hand and sleeve are moved rearwardly they serve to move the minute shaft rearward to stop the alarm. The pinions 226, 228 and 230 are elongated to permit axial movement of the minute shaft 2I0 with respect thereto without disturbing the driving relation of the elements.

The alarm mechanism is generally similar to that shown in Fig. 5 and its operation is controlled by the detent 232 which is normally urged to retracted position by means of the spring strip 234. The free end of the spring strip 234 is formed with a fork surrounding the shaft 2I0 adjacent the upper face of the pinion 230 and when the minute shaft 2") is in its normal operating position the detent 232 is held in a raised position to engage the pins 233 extending downward from the spring housing 23I of the alarm mechanism. When the minute shaft 2 I0 is moved axially forward by the sleeve 2I6 the spring strip 234 moves to retract the detent 232 from engagement with the pins 233 whereupon the housing 23I and plate I30 are rotated to operate as an alarm.

Retarding or escapement means such a the spring finger 235 shown in Fig. 10 engage the pins 233 to prevent free or unrestricted rotation of the plate I30 of the alarm mechanism.

The axial movement of the sleeve H6 is controlled by means of an alarm setting hand 236 which is located adjacent the face of the dial 238 and beneath the hour hand 2I4. The alarm setting hand is movable to any desired position by movement of the rotatable bezel 240 on the front of the watch case which carries a finger 242 extending inward to engage the end of the alarm setting hand. The central portion of the alarm setting hand is provided with a collar 244 fitted to rotate within a central opening in the dial 238. The inner face of the collar 244 of the alarm setting hand is formed with an inclined element 246 which is shown in Fig. 9 is in the form of a cam that normally rides over the outer surface of wheel 2 I 8 and about thecollar 2 I 6. The wheel 2I8 is however provided with a recess 248 for receiving the cam element 246 when the wheel 2I8 and hour hand 2I4 have moved to a predetermined position as determined by the alarm setting hand. The cam element 246 thus normally serves to hold the wheel 2| 8 and sleeve 2| 6 depressed against the action of the arcuate spring 220 and normally serve to force the minuteshaft 2I0 rearward to alarm stopping position. When the hour hand moves to a position in which it overlies the alarm setting hand, the cam 246 will be in a position to enter the recess 248 whereupon the spring 220 moves wheel 2I8 and sleeve 2I6 axially so that the outer end of the sleeve pushes against the annular extension 224 on the minute hand and causes the minute hand and shaft 2 I I] to move forward. Sprin strip 234 then operates to withdraw the detent 232 from the pins 233 on the alarm mechanism. The alarm will accordingly be released for operation at a predetermined time as previously described.

In order to stop the alarm it i necessary only to rotate the bezel 240 so as to move cam 246 of recess 248 and force wheel 2I8 rearward. The sleeve 2I6 then pushes against the shoulder 223 on minute shaft 2I 0 so that the latter shaft is moved rearward against the action of the spring strip 234 and detent 232 is raised into position to be engaged by a pin 233 on the spring housing 23I of the alarm mechanism. The alarm is then stopped.

The manner in which the alarm mechanism is set and controlled may obviously be varied considerably and the timing mechanism employed also can be changed to use any conventional or preferred timing mechanism. While I have illustrated and described several typical and preferred forms of mechanism embodying my invention, it will be apparent that numerous changes and modifications may be made in the form and arrangement of the elements of the combination and other types of tapping, vibrating or oscillating members may be actuated by the alarm mechanism to impart a rubbing, scraping, tapping or successive pressing movement to the body of the wearer so as to awaken or notify the user. The construction may be incorporated into any type of watch or time-piece but if desired it may in the alternative be constructed for application to conventional watches so as to be sold as an attachment for existing time-pieces. In view thereof it should be understood that the particular embodiment of my invention shown in the figures of the drawings and herein described is intended to be illustrative only and is not intended to limit the scope of my invention.

I claim:

1. An alarm time-piece comprising timing elements, an alarm member, means for holding the alarm member in engagement with a users body, a spring for moving the alarm member, escapement means controlling movement of the alarm member, said timing elements including an axially movable shaft having an hour hand secured thereto and means movable by said shaft on axial movement of the latter for controlling operation of said alarm mechanism.

2. An alarm time-piece comprising timing elements, an alarm member, means for holding the alarm member in engagement with a users body, a spring for moving the alarm member, escapement means controlling movement of the alarm member, said timing elements including an axially movable shaft having a minute hand secured thereto and means movable by said shaft on axial movement of the latter for controlling operation of said alarm mechanism.

OLIVER M. SCHAFER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 944,948 Connolly Dec. 28, 1909 1,163,942 Mijake Dec. 14, 1915 1,927,765 -Wisely Sept. 19, 1933 2,192,505 Raybuck Mar. 5, 1940 2,223,243 Axelrod Nov. 26, 1940 2,463,087 Christensen Mar. 1, 1949 FOREIGN PATENTS Number Country Date 211,696 Switzerland Jan. 2, 1941 228,245 Switzerland Nov. 1, 1943 249,419 Switzerland Apr. 1, 1948 251,703 Switzerland Aug. 1, 1948 370,448 France Dec. 20, 1906 726,827 France Mar. 14, 1932

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