US3052082A

US3052082A - Electric timepiece

Info

Publication number: US3052082A
Application number: US23276A
Authority: US
Inventors: Beyner Andre; Besson Rene
Original assignee: Ebauches SA
Current assignee: Ebauches SA
Priority date: 1959-04-20
Filing date: 1960-04-19
Publication date: 1962-09-04
Anticipated expiration: 1979-09-04

Description

Sept. 4, 1962 A. BEYNER ETAL ELECTRIC TIMEPIECE 2 Sheets-Sheet 1 Filed April 19, 1960 IN VE N TOPS VI E N w m U N W n g 8mmv EBA E wmy ARDu p 1962 A. BEYNER ET Al. 3,052,082

ELECTRIC TIMEPIECE Filed April 19. 1960 2 Sheets-Sheet 2 P/AE' H] AL 1 l IN VE'N TOPS ANDRE BEYNEI? RENE BES A TTOFPNEY United States Patent ()1 3,052,082 ELECTRIC TIMEPIECE Andre Beyner, Neuchatel, and Ren Besson, Les Loges,

Fontainemelon, Switzerland, assignors to Ebauches S.A., Neuchatel, Switzerland, a Swiss firm Filed Apr. 19, 1960, Ser. No. 23,276 Claims priority, application Switzerland Apr. 20, 1959 8 Claims. (Cl. 58-23) The present invention relates to an electric timepiece.

This electric timepiece is characterised by the fact that a casing ring electrically insulated from the frame of the movement surrounds the latter and provides the electrical connection on the one hand between the motor and one terminal of an accumulator enclosed in the case, and on the other hand between the said accumulator and a terminal for re-charging the latter, which terminal is mounted on the case in such manner as to be electrically insulated therefrom.

One constructional form of the subject of the invention is illustrated by way of example in the drawings, in which only the parts necessary for an understanding of the invention have been shown.

FIGURE 1 is a diagrammatic plan view partly in fragmentary form and partly in section, of the movement of an electric timepiece,

FIGURE 2 is a fragmentary axial section through the timepiece with its case, to a larger scale,

FIGURE 3 is a plan view of the movement plate, to a smaller scale, in which only its outer contour has been shown,

FIGURE 4 is a section through a detail along the line IV--IV of FIGURE 1,

FIGURE 5 is an elevational view of a detail, partly in section, and

FIGURE 6 is a circuit diagram in which the main parts have been diagrammatically represented, and which illustrates the principle of operation of the motor.

The illustrated timepiece is a wrist watch having a round movement. The latter comprises a circular movement plate 1 having a portion 1a of larger diameter, as also an external lug 1b diametrically opposite the part In (FIGURES l and '3).

The electric motor of the said watch comprises a stator having a core 2 of horseshoe shape, which is terminated by two

pole pieces

3a and 3b. The core is in turn formed of two ferromagnetic strips 2a and 2b (FIG- URE 4) bedded in a layer 4 of electrically insulating material. The core carries an electric winding 5 formed of two parts separated by a sleeve 6 mounted on the strips 2a and 212, at the mid-point of the latter. The winding is covered by a protective packing 7 of electrically insulating plastic material, which has a substantially square external section, except at the location of the section line IV-IV, where the packing has an internally extending projection 7a covering a resistance 8, the function of which will hereinafter be indicated. The stator is fixed to the movement plate 1 by the lug 1b on the latter, which is introduced into a recess corresponding to the packing 7, and by screws (not shown) which extend through holes 9a and 9b in the

pole pieces

3a and 3b, from which they are electrically insulated by insulating bushes 10 internally lining said holes.

The rotor of the motor comprises a movable armature formed of a disc 11 of ferromagnetic material having four

vanes

11a, 11b, 11c and 11d. The disc is mounted on the staff 12 of the balance wheel, which is not shown in FIGURE 1, but is diagrammatically represented at 13 in FIGURE 6. It is to be noted that the bridges of the movement, which partially cover the movable armature 11, also have not been shown.

ice

The driving pulses are controlled by thebalance wheel and an associated switch. Staff 12 of the balance wheel carries for this purpose a dog 14 acting, in its passage, on two

resilient switch blades

15 and 16 fixed to the plate 1 by means of an insulating stud 17 and electrically connected to the lead-out wire 18a of the winding 5 by a metal bar 19. It is to be noted that the bar is also insulated from the fixing screw of the stator, which extends through the hole 9a. When the dog 14 is in contact with either one of the resilient blades 15- and 16, it connects to ground in common with one of the poles of an electric current source, as will hereinafter be described, and further connects with the lead-out wire of the winding 5. The current then flows through the winding in such manner that the movable armature 11 is thus subjected to a pulse. It is to be noted that two pins 20 and 21 are in addition fixed to the frame of the movement, at a bridge (not shown) which extends over the

blades

15 and 16. When the blades are deformed by the dog 14, one of the blades, depending upon the direction of movement of the balance wheel, comes into contact with one of the pins 20 and 21, whereby the grounding of these blades is further ensured. The motor drives the hands (not shown) through a normal mechanism, for example a lever, which also has not been shown, and which does not form part of the present invention.

The movement is surrounded by a casing ring 22 which bears on the insulating packing 7 of the stator, so that it is not in electrical contact with the frame of the movement. In order to avoid accidental contact, that portion 22a of the ring 22 which is situated opposite the portion 1a of the movement plate 1 is of larger diameter than the remainder of the ring 22. In addition, the external diameter of the portion 1a of the plate is smaller than the external diameter of the insulating packing 7 of the stator. Consequently, a safety space 23 remains between the plate and the ring 22. The ring has internal resilient lugs 22b bearing against a dome 24 of the envelope of an accumulator 25 (FIGURE 2) lodged in the back 26 of the watch case. This dome constitutes one of the poles of the accumulator, the other pole consisting of a dome 27 of the envelope, which dome is in contact with the back 26, that is to say, with ground. An annular ring 28 is disposed between the dome 27 and the back to ensure electrical contact between these two parts. The casing ring 22 has in addition an inner lug 22c (FIGURES 1 and 6) connected to the lead-in Wire 1812 of the winding 5. Thus, the electrical connection between the motor and the accumulator is ensured on the one hand through ground and on the other hand through the casing ring 22. It is to be noted that the resilient tongues 22b serve both to ensure electrical contact and to suspend the movement resiliently in the case.

The movement is in addition surrounded by a cage 29 (FIGURES 2 and 5) bearing against the case body denoted by 30. The cage is formed with an internally threaded hole 31 (FIGURE 5) to receive a screw laterally locking the plate 1, the object of which screw is to ensure good electrical contact between the said plate and the cage 29. The latter has two passages 32 through which access can be had by means of a screwdriver to the screws by which the feet (not shown) of the dial denoted by 33 (FIGURE 2) are secured.

It is to be noted that the accumulator 25 is maintained in position in the back 26 by a ring 34 of electric'ally insulating material, which is screwed into an internal screw thread in the ledge 26a of the back 26. A fluid-tight packing 35 is disposed between the accumulator 25 and the back 26. The packing has the object of preventing any electrolyte which may escape from the accumulator through the joint 36 between the

domes

24 and 27 from spreading into the case and more especially from reaching the movement.

The illustrated watch comprises in addition a terminal for recharging the accumulator. The terminal consists of a rod 37 surrounded by an insulating sleeve 38 which is in turn engaged in a sleeve 39 fitted in the case body 30. The rod 37 bears at its inner end against an external lug 22d of the casing ring 22, which extends freely into a recess 40 in the cage 29. When a current source (for example a dry cell) is placed in contact with the outer end of the rod 37, on the one hand, and with the case on the other hand, the accumulator 25 is recharged, the electrical connection being effected through the casing ring 22. A detachable cap 41 is fixed on the sleeve 39 to prevent the outer end of the rod 37 from being accidentally brought into contact with ground, for example by moisture of the ambient air or by the perspiration of the wearer of the watch.

Finally, it is to be noted that the hand setting stem of the watch, which is represented only by its axis 42 (FIGURE 1), passes between the two parts of the winding by way of a recess (not shown) formed for this purpose in the insulating packing 7, level with the sleeve 6.

The operation of the illustrated watch is diagrammatically illustrated in FIGURE 6. It will be seen in this figure that with regard to the series connected accumulator and motor, one of the poles of the accumulator 25 is connected to ground, while the other pole is connected to the ring 22 by the lugs 22b of the latter. The lug 22c is connected to the input terminal of the winding 5, while the output terminal of the latter is connected to the blades and 16. The latter are grounded when the dog 14 is in contact with them and when it applies them against the pins and 21. The dog is in turn connected to ground by the staff 12 of the balance wheel and by the spiral spring denoted by 43, because since the bearings of the stafi 12 consist of rubies, the staff is not directly in contact with the frame of the movement. In this figure, the armature 11 mount- -ed on the staff 12 of the balance wheel 13 is shown at a distance from the stator, whereas in practice it is pivotally mounted between the

pole pieces

3a and 3b above which there extend the ends of its vanes 11a to 17a of the insulating packing 7 of the stator is connected in parallel with the winding 5. It has the object of protecting the contact formed by the dog 14 and the

blades

15 and 16, and it may be replaced by a diode.

What we claim is:

1. In an electric timepiece having a movement wherein an electric motor has a pair of motor terminals and a stator winding interconnecting said terminals, a case enclosing said movement, a recharging terminal mounted on said case and electrically insulated from said case, and an accumulator located within said case and having a pair of accumulator terminals connected in series electrical circuit with said motor across said motor terminals, the improvement which includes an electrically conductive support for said movement within said case and having resilient lugs electrically conductively supported by one of said pair of accumulator terminals, and said movement having electrical insulation embedding said stator winding and said insulation being engaged with said support whereby said movement is supported by said support and said resilient lugs thereof, electrically insulated from said support, said support being disposed electrically conductively between one of said pair of motor terminals and said one of said pair of accumulator terminals as a component of said series electrical circuit, and said support being electrically conductively between said recharging terminal and said one of said accumulator terminals as a conductor for said accumulator to be recharged.

2. In an electric timepiece as claimed in claim 1, wherein said electrically conductive support includes a lug electrically contacting said recharging terminal.

3. In an electric timepiece as claimed in claim 1, wherein the other accumulator terminal of said pair of terminals of said accumulator is grounded to said case, and the other motor terminal of said pair of motor terminals is grounded to said case.

4. In an electric timepiece as claimed in claim 1, wherein a cage is disposed between said movement and said case and is in grounded interconnection of said other motor terminal of said pair of motor terminals and said case, and said other accumulator terminal of said pair of accumulator terminals abuts the back of said case in an electrically grounded relation to said case.

5. In an electric timepiece having a movement wherein an electric motor has a pair of motor terminals and a stator winding interconnecting said terminals, a case enclosing said movement, a recharging terminal mounted on said case and electrically insulated from said case, and an accumulator located within said case and having a pair of accumulator terminals connected in series electrical circuit with said motor across said motor terminals, the improvement which includes an electrically conductive casing ring surrounding said movement within said case and having resilient lugs electrically conductively supported by one of said pair of accumulator terminals, and said movement having electrical insulation embedding said stator winding and said insulation being engaged with said casing ring whereby said movement is supported by said ring and said resilient lugs thereof, electrically insulated from said casing ring, said casing ring being disposed electrically conductively between one of said pair of motor terminals and said one of said pair of accumulator terminals as a component of said series electrical circuit, and said casing ring being electrically conductively between said recharging terminal and said one of said accumulator terminals as a conductor for said accumulator to be recharged.

6. In an electric timepiece having a movement wherein an electric motor has a pair of motor terminals and a stator winding interconnecting said terminals, said winding being on a stator core of said motor, a case enclosing said movement, a recharging terminal mounted on said case and electrically insulated from said case, and an accumulator located within said case and having a pair of accumulator terminals connected in series electrical circuit with said motor across said motor terminals, the improvement which includes said stator core having a substantially circular curvature and said winding and core co-extending more than in terms of length of the core, a substantially circular frame of said movement, an electrically conductive substantially circular casing ring surrounding said frame in a peripherally spaced relation thereto within said case and having resilient lugs electrically conductively supported by one of said pair of accumulator terminals, and said movement having electrical insulation embedding said stator winding and said insulation being engaged with said frame and with said casing ring radially outward from said frame whereby said frame is supported in said peripherally spaced relation to said ring by said insulation, said casing ring being disposed electrically conductively between one of said pair of motor terminals and said one of said pair of accumulator terminals as a component of said series electrical circuit, and said casing ring being electrically conductively between said recharging terminal and said one of said accumulator terminals as a conductor for said accumulator to be recharged.

7. In an electric timepiece as claimed in claim 6, wherein said insulation embedding the stator winding has an opening receiving a hand-setting stern of said movement through said opening, and said stator winding is in two sections in series and said sections are dis posed on opposite sides of said opening.

8. [In an electric timepiece having a movement wherein an electric motor has a pair of motor terminals and a stator Winding interconnecting said terminals, a case enclosing said movement, a recharging terminal mounted on said case and electrically insulated from said case, and an accumulator located within said case and having a pair of accumulator terminals connected in series electrical circuit With said motor across said motor terminals, the improvement which includes an electrically conductive casing ring surrounding said movement within said case, said casing ring having resilient internal lugs electrically conductively supported by one of said pair of accumulator terminals and having an external terminal lug and an internal terminal lug, and said movement having electrical insulation embedding said stator winding and said insulation being engaged with said casing ring whereby said movement is supported by said ring and said resilient lugs thereof electrically insulated from said casing ring, said internal terminal lug being electrically conductively connected with one of said pair of motor terminals placing said ring in said series electrical circuit, and said external terminal lug being electrically oonductively connected with said recharging terminal making said ring a conductor for said accumulator to be recharged.

References (Iited in the file of this patent UNITED STATES PATENTS 2,730,634 De Saint-Vaulry Jan. 10, 1956 2,791,732 Jones May 7,, 1957 2,907,810 Detwiler et al. Oct. 6, 1959 2,916,871 Wegner Dec. 15, 1959 2,938,327 Vogel May 31, 1960 FOREIGN PATENTS 1,058,942 Germany June 4, 1959