US2580597A - Timepiece movement with intermittent seconds indicator - Google Patents

Description

1952 FRITZ-ANDRE ROBERT-CHARRUE 2,580,597

' TIMEIPIECE MOVEMENT WITH INTERMITTENT SECONDS INDICATOR Filed Jun 2, 1949 AHorn LY Patented Jan. 1, 1952 TIMEPIECE MOVEMENT WITH INTERMIT- TENT SECONDS INDICATOR Fritz-Andre Robert-Charrue, Le Locle, Switzerland, assignor to Ebauches S. A., Neuchatel, Switzerland, a Swiss firm Application June 2, 1949, Serial No. 96,637 In Switzerland June 9, 1948 7 Claims. (CI. 5859) 1 This invention relates to a mechanism of idling seconds for movements in timepieces, that is to -say, a mechanism in which the seconds hand advances only once every second.

One of the features of this invention is to transform the ordinary seconds movement of timepieces in which the seconds hand advances five times per second, each time by one-fifth of a second, into the stated improved mechanism.

This mechanism of idling seconds comprises two coaxial wheels, one of which is a driving wheel, the other one being driven, both forming a part of the gear train of the second hand. These two wheels are connected through a spring: they have the same number of teeth; the diameter of the driven wheel is slightly smaller than that of the driving wheel. The said mechanism further comprises a braking or stopping device which cooperates with the two coaxial wheels aforesaid, in such a manner that the pa sage of the teeth of the driving wheel over said brak ng or stopping device di places the latter sufficiently to allow the intermittent rotation of the driven wheel, which is brought about by the action of the spring.

The driven wheel is geared through a pinion to the wheel of seconds of the timepiece. The two coaxial wheels and the braking or stopping device are so designed, and their relative motions so regulated, that, at each intermittent displacement of the driven wheel, the seconds wheel and hand move by one second.

The foregoing and other features of this invention will appear from the following detailed descript on and from the attached drawing, which refer, by way of illustration but not of limitation, to an embodiment thereof.

Fig. 1 is a plan view of a watch, the movement of which includes the mechanism of idling seconds object of this invention.

Fig. 2 is a plan view of said mechanism.

Fig. 3 is a detailed sectional elevation alon line IIIIII of Fig. 2.

Fig. 4 is a large scale detailed view of the coaxial wheels and braking or stopping device.

Referring to the drawing, the illustrated watch is designated I. Its movement comprises a wheel of seconds 2, driven by pinion 3. A seeonds hand I5 is rigidly mounted on the shaft I5 of wheel 2. It further comprises two coaxial wheels, 4 and 5, mounted above each other. The lower wheel 4 (Fig. 2) is a driving Wheel, while the upper wheel 5 is driven; driven wheel 5 is mounted idle around the end of axis 6 on which wheel 4 is rigidly mounted. Axis 6 is driven by the watch These two coaxial wheels are connected by means of a spiral spring "I, the inner end oi which is attached to axis 6, and the outer end of which is attached to a pin borne by driven wheel 5. The diameter of dr ving wheel 4 is slightly greater than that of driven wheel 5; however, these two wheels have the same number of teeth, equal to the number of teeth of the wheel of seconds 2.

As seen clearly in Fig. 3, driven wheel 5 meshes with p nion 3: the latter, in turn, meshes with wheel 2 as shown in Fig. 4.

A pawl 9, borne by a spring I0, cooperates with wheels 4 and 5. and tends to oppose their rotation in the direction of arrow I I. A spoke of wheel 4 carries a pin I2 serving as stop for a spoke of wheel 5. Some of the spokes of said wheel 5 are provided with notches I3, which mav receive pin l2, depending upon the relative setting of wheels 4 and 5: each of these notches I3 has a depth different from that of the other notches: so that, depending upon which spoke of wheel 5 is set to cooperate w th pin I2, the relative position of the two wheels 4 and 5, upon contact of the pin with the notched spoke, can be varied. A jumper I4, mounted on a spring, cooperates with wheel 2 to eliminate any motion, oscillation or vibration of the seconds hand I5 after each of its d splacements.

This mechanism operates as follows:

Wheel 4 being driven in the direction of arrow I I (Fig. 2), pawl 9 is sprung and displaced by the teeth of wheel 4. Driven wheel 5 being stopp d, spiral spring I t ghtens. At a given instant, the amp itude of this di placement is great eno gh to allow the pas a e of a tooth of wheel 5, the latter being actuated in rotation in the direction of arrow I I by spiral spring I; at that instant, wheel 5 rotates until such of its spokes as has been set to cooperate with pin I2 comes to strike and rest against said pin. This rotation of wheel 5 causes, through the meshing train of pinion 3 and wheel 2, a displacement of the seconds hand I5 corresponding on the time scale I! (diagrammatically represented in Fig. 1) of the face of the watch, to one second. To secure this result, the shape of the teeth of wheels 4 and 5 and that of pawl 9 must be so accurately designed and shaped that, as wheel 4 moves step by step each one-fifth of a second, pawl 9 should release one tooth of wheel 5 at the end of each fifth movement of wheel 4.

I claim:

1, In a timepiece movement, a mechanism of idling seconds, comprising, as part of the gear train of the seconds hand, a first driving wheel; a second driven wheel coaxial with said first driving wheel, and having the same number of teeth as, and a slightly smaller diameter than, said first driving Wheel, said driven wheel being mounted idle over the shaft of saiddriving. wheel; a springconnecting said first driving and sec.- ond driven wheels; astopping and braking device cooperating with the teeth of said first driv.-.

ing and second driven wheels to allow by its displacement upon the passage of eachtooth 0f the driving wheel a partial and intermittent rota tion of said driven wheel as a result'ofthe ac tion of said spring on said driven wheel.

2. A mechanism as claimed in claim 1 in which said displacement and said partial andintermia tent rotation of said driven wheel'are controlled by the relative profiles of the teeth of said first driving and second driven wheels and ofsaid braking and stopping device.

3 -.-,In;a mechanism as-claimedinclaixn La secands wheel, carryingaseconds hand; a; pinion meshing with said seconds wheel and saiddriven wheel; said partial. and intermittent rotation of said driven wheel corresponding to a displacement of saidseconds hand of one second on-the timescale of said timepiece.

4. A mechanism as claimed in claim 1 in which said spring connectingsaid driving and, driven wheels is a spiral spring attached at one end to said shaft of saiddriving wheel, and at the other end to said driven wheel.

5. A mechanism as claimed in claim lin which saiddriving wheel is-providedwith radial spokes, one'of said spokes carrying a pin, and in which said' dri-ven wheelis providedwith radialspokes, and in which-a spoke of said driven wheel abuts said pin at the end of each ofits partial and intermittent rotation.

6; In a timepiece movement, a mechanism of idling seconds, comprising, as part of the gear train of the seconds hand, a first driving wheel; a second driven wheel coaxial with said first driving wheel, and having the same number of teeth as, and a slightly smaller diameter than, said first driving. wheel, said driven wheel being mounted idle over the shaft of said-driving wheel; a spring connecting said first driving and said second driven wheels; a seconds Wheel, carrying a seconds hand; a pinion meshing with said seconds Wheel and-said driven wheel; a stopping and braking device engaging the teeth of said driving and driven wheels, the relative profiles of said teeth and of said device causing the temporary disengagement of said device from the teeth of said driven wheel after passage of each tooth-o1 said driving wheel over said device, said disengagement allowing a partial and intermittentrotation of said driven wheel caused by the action of said spring and resulting in a displacement of said seconds, hand of onesecond on-the time scale of said timepiece.

7. A mechanism as claimed in claim 6 comprising further a .jumper cooperating with said seconds wheel.

FRITZ-ANDRE ROBERT-CHARRUE.

REFERENCES CITED The following references are of recordinthe fileof this patent;

UNITED STATES PATENTS Number Name Date 224,635 Bonzon Feb. 17, 1880 458,745 Benjamin Sept. 1, 1891 FOREIGN PATENTS Number Country Date 2.1;489 GreatBritain- Oct.- 3, 1902

Images