Control device for clock mechanisms

Description

[0001] The present invention relates to a control device for clockwork mechanisms comprising: two control cams, each comprising drive means, and arranged to be selectively located respectively in a first and a second plurality of predefined angular positions; a manually operated mechanism comprising an external control member, and arranged to allow a user to simultaneously move the two control cams from one predefined angular position to another, so as to cyclically occupy, by the two control cams, respectively the first and the second plurality of predefined angular positions;at least two cam followers having first ends arranged to cooperate respectively with the two control cams, the first ends of the two cam followers being arranged so that each, according to the predefined positions occupied by the two column wheels, is either resting on a crest of one of the two control cams, or lowered into a hollow of the latter, each of the two cam followers further having a second end arranged to cooperate with a clockwork mechanism so as to switch said clockwork mechanism in one direction when the first end of the cam follower lowers into a hollow of one of the two control cams, and in the other direction when it rises to rest on a crest of the latter. EARLIER ART

[0002] We are familiar with timepieces that incorporate several switchable mechanisms that must be activated simultaneously by a user. These types of timepieces are often equipped with a control cam, most commonly a column wheel, which has a contact profile designed to cooperate with multiple levers, each associated with one of the mechanisms to be switched. The cam also includes drive means that allow the user to rotate the control cam. Designers of such cam-operated timepieces regularly encounter certain difficulties. Indeed, the various mechanisms of these timepieces cannot always be arranged in the immediate vicinity of the control cam. Therefore, it is often necessary to design levers with complex shapes and considerable lengths to connect the control cam to the different mechanisms to be switched.

[0003] Solutions to this problem have already been proposed. Patent document EP 1 960 846 B1, in particular, describes a control device comprising two coaxially arranged column wheels, which are driven by the same ratchet. The control device described in this earlier document is specifically designed to simultaneously control a chronograph mechanism and an hour counter. In the example described, the column wheel that controls the chronograph mechanism is located on the caseback side of the movement, while the column wheel that controls the hour counter is located on the dial side. This earlier solution is satisfactory when the mechanisms to be switched simultaneously are not located on the same side of the movement plate. However, its usefulness is much more limited when the mechanisms to be switched are located at a distance from each other on the same side of the movement.

[0004] EP 1 372 117 A1 discloses a chronograph mechanism with a control and switching function, and comprising two column wheels mounted on the same axis, external manual control means simultaneously moving the ratchets of the column wheels from one state to another, two rockers allowing a clockwork mechanism to be moved according to the position of the noses in relation to the hollows and the tops of the columns, two control rockers carrying ratchets allow the column wheels to be driven by one step. BRIEF SUMMARY OF THE INVENTION

[0005] One object of the present invention is to overcome the drawbacks of the prior art just described. The present invention achieves this object, as well as others, by providing a control device for clockwork mechanisms, which conforms to the attached claim 1.

[0006] According to the invention, the manually operated mechanism of the control device comprises, on the one hand, a control rocker arranged to cooperate with the external control member so as to move from a rest position to a tilted position when the user actuates the external control member and then return to the rest position when the external member is released; and on the other hand, first and second actuating means carried by two opposite ends of the control rocker and arranged to cooperate respectively with the drive means of the two control cams, so as to allow the latter to be driven from one predefined angular position to another by actuating the external control member. Thanks to the features of the invention just described, it is possible to simultaneously increment two column wheels arranged at a distance from each other.

[0007] According to a particular embodiment, the two control cams are circular cycle cams, preferably column wheels.

[0008] In accordance with an advantageous embodiment, the two control cams have the same number of hollows and the same number of bumps. BRIEF DESCRIPTION OF THE FIGURES

[0009] Other features and advantages of the present invention will become apparent from the following description, given solely by way of non-limiting example, and made with reference to the accompanying drawings in which: there figure 1 represents a chronograph mechanism of the prior art equipped with a column wheel controlling the three chronograph functions; the figure 2 illustrates an earlier art retrograde needle display device that is associated with a fraction-of-a-second counter on a chronograph; the figure 3 is a perspective view showing the top of a control device for clockwork mechanisms which conforms to a particular embodiment of the invention. DETAILED DESCRIPTION OF A METHOD OF IMPLEMENTATION

[0010] The control device for watch mechanisms, which will now be described in more detail as an example, is intended for integration into a chronograph watch designed specifically to indicate elapsed fractions of a second using a retrograde hand combined with a fraction-second counter. As will be seen in more detail later, the chronograph watch in this example requires the simultaneous switching of the chronograph mechanism and the fraction-second display device.

[0011] There figure 1 The attached illustration represents, by way of example, a chronograph mechanism known as such, which is likely to constitute the chronograph mechanism of the chronograph watch into which the control device of this example is intended to be integrated. Referring to the figure 1 We can see a three-phase column wheel arranged to control the three classic functions of a chronograph: starting, stopping, and resetting. The column wheel (referenced 1) conventionally comprises, in its lower section, a ratchet mechanism made up of eighteen saw teeth 2, and in its upper section, six columns 3 evenly spaced around a circle. It should be noted that the ratio between the number of teeth 2 of the ratchet mechanism and the number of columns 3 is equal to three, thus the column wheel operates in three phases.

[0012] The chronograph mechanism shown also includes a manually operated mechanism comprising a large rocker 5 formed of two arms extending on either side of its pivot axis. One end (referenced 4) of the rocker 5 is arranged to cooperate with an external control member (not shown), and the other end carries a ratchet (not referenced) which is arranged to cooperate with the ratchet of the column wheel 1. When a user presses the pusher serving as the external control member, the large rocker 5 pivots in the direction indicated by arrow F, driving the column wheel 1 via the ratchet. Referring again to the figure 1 As can be seen, by pivoting one step, the column wheel lifts the hammer 6, which releases the heart 7 from the center wheel 8. Simultaneously, the intermediate lever 9 lowers between two columns, causing the intermediate wheel 10 to mesh with the center wheel 8, thus starting the chronograph mechanism. When the user presses the pusher again, the intermediate lever 9 is again lifted by a column, causing the intermediate wheel 10 to move away from the center wheel 8. At the same time, the brake 11's beak, which until then had remained in its initial position against column 3a, lowers into the space between columns 3a and 3b, so that the rounded part 12 of the brake comes to rest against the center wheel 8. This stops the chronograph. Finally, a third press on the pusher resets the chronograph.Indeed, the hammer 6 lowers itself again against the heart 7 so as to bring the center wheel back to zero.

[0013] There figure 2 This illustrates, by way of example, a retrograde hand display device that is known as such. The display device shown is likely to be the fraction-second display device of the chronograph watch into which the control device of this example is intended to be integrated. It will be understood that this chronograph watch also includes a fraction-second counter wheel that is part of a gear train (not shown) of the chronograph mechanism of the chronograph watch. The seconds wheel 8 of this mechanism can, for example, mesh with the pinion of a first intermediate wheel (not shown), and the wheel of this intermediate wheel can mesh with the pinion (not shown) of the fraction-second counter wheel.The gear ratios of the chronograph gear train just described can be chosen so that, when the chronograph seconds wheel 8 rotates at a speed of one revolution per minute, the fraction-of-a-second counter wheel rotates at a speed of one revolution per second, the counter being a tenth-of-a-second counter. For example, the chronograph seconds wheel may have 80 teeth, the pinion and wheel of the first intermediate wheel may have 10 and 75 teeth respectively, and the pinion of the tenth-of-a-second counter wheel may have 10 teeth.

[0014] Referring again to the figure 2 We can see a pinion 123, a retrograde needle 115 rigidly mounted on the pinion's axis, a series of graduations arranged along an arc of a circle to form a scale 119, a snail 125 mounted on the axis of a moving part of the tenth-of-a-second counter (not shown), so as to rotate in unison with the latter at a speed of one revolution per second, a rake 127 equipped with a toothed sector 129, and a feeler 131 rigidly mounted on the rake. We can also see a column wheel 135 comprising a ratchet formed of eighteen teeth 137 and six columns 139 mounted on the ratchet wheel plate. It should be noted that the ratio between the number of teeth of the ratchet 137 and the number of columns 139 is equal to the ratio between the number of teeth of the ratchet 2 and the number of columns 3 in the figure 1 It is therefore necessary to exert three pressures on the pusher (not shown) for a column 139 of the column wheel 135 to take the place of the previous one.

[0015] Returning now to the fraction-of-a-second indicator, we can see that the rake 127 is mounted to pivot around an axis 133 and that it is fitted with a beak 141 which is returned towards the columns of the column wheel 135 by a spring 143. The figure 2 illustrates the display device in its configuration following the stop of the chronograph. It can be seen that, in this configuration, the beak 141 is lowered between two columns 139, so that the feeler 131 is free to come to rest against the periphery of the snail 125, the rack 127 thus being in its reading position. It should also be noted that, in the reading position, the toothed sector 129 of the rack engages with the pinion 123, so that the angular position of the retrograde hand 115 is determined by that of the snail 125. It will also be understood that, if the chronograph is then reset by rotating the column wheel 135 by one additional step, the beak 141 is lifted by a new column, which causes the rack 127 to pivot counterclockwise, so that the toothed sector 129 disengages from the pinion 123.The retrograde hand 115 is then free to return to its position above the graduation corresponding to the zero of the scale 119. It will be understood that the column wheel 135 and the column wheel 1 of the chronograph mechanism must be incremented simultaneously.

[0016] Patent document WO 2020 / 044258 A1 in the name of the applicant contains a more detailed description of the retrograde needle display device of the figure 2 This document is incorporated by reference into this description.

[0017] There figure 3 is a top view of a control device according to an exemplary embodiment of the invention. Referring to this figure, one can see a first column wheel 15 comprising a ratchet wheel 17 and six columns 19 mounted on the ratchet wheel plate, and a first jumper 21 which is held against the ratchet of the first column wheel by a first spring 23, so as to define eighteen stable angular positions, called predefined positions, of the first column wheel. The figure 3 also shows a second column wheel 35 comprising a ratchet wheel 37 and six columns 39, and a second jumper 41 brought back against the ratchet of the column wheel 31 by a second spring 43. It will be understood that the second column wheel therefore also has eighteen predefined stable angular positions.

[0018] There figure 3 This further illustrates a manually operated mechanism arranged to allow a user to simultaneously increment the two column wheels 15 and 35. This mechanism comprises, firstly, an external control element, symbolically represented by an arrow (referenced P). It also includes a large rocker 51 formed by two arms 55, 57 extending on either side of the pivot axis 53 of the rocker 51. The rocker 51 is arranged to cooperate with the external control element so as to move from a rest position (represented in the figure 3 ) to a tilted position (not shown) when the user actuates the external control element, and then to return to the rest position when the external element is released. It can be seen that each of the column wheels is arranged near the distal end of one of the two arms 55, 57, and that two pawls 25, 45, which are respectively articulated on the distal ends of the two arms 55, 57, are arranged to cooperate respectively with the ratchets of the two column wheels 15, 35, so as to allow the latter to advance step by step. The figure 3 shows two more leaf springs 27, 47 which are arranged to return the two pawls 25, 45 against the ratchets of the two column wheels 15, 35.

[0019] In this example, the external control element consists of a pusher (not shown) which is mounted on the case of the chronograph watch. When a user presses the pusher, the inner end of its stem pushes back the arm 57 of the control rocker 51, so that the latter pivots clockwise (as shown in the figure 3 ) to come into the tilted position. When the user then releases the push button, it is returned to the rest position, so that its inner end moves away from the control rocker 51. The latter is then free to return to the rest position under the action of its own return spring (not shown).

[0020] Referring again to the figure 3 , we can see that, in the illustrated example, the ratchet teeth 17, 37 of the two column wheels are not arranged in the same direction, the column wheel 15 being intended to be incremented clockwise, while the column wheel 35 is intended to be incremented counterclockwise. It can also be seen that the two column wheels 15, 35 are arranged on the same side (above in the drawing) of a straight line passing through the two ends of the control rocker 51. Thus, when the latter pivots around its axis 53 in a clockwise direction, its arm 55 moves away from the column wheel 15, while its arm 57 moves towards the column wheel 35. Under these conditions, on the one hand, the pawl 25 which is pivoted on the end of the arm 55, is in a position to pull on a tooth of the ratchet 17, and on the other hand, the pawl 45 which is pivoted on the end of the arm 57, is in a position to push back a tooth of the ratchet 37.

[0021] In accordance with the example shown in the figure 3 The column wheel 15 is arranged between the axis 53 and the pawl 25, while at the other end of the rocker arm 51, the pawl 45 is arranged between the column wheel 35 and the axis 53. Thus, the pawl 25 is returned by the spring 27 against the part of the column wheel 15 that is on the side opposite the axis 53, while the pawl 45 is returned by the spring 47 against the part of the column wheel 35 that is on the side facing the axis 53. It will be understood that, according to other embodiments, the column wheels could both be arranged between one of the pawls and the pivot axis; all other things being equal, the two column wheels would then rotate clockwise.According to yet other embodiments, the two pawls could both be arranged between one of the column wheels and the pivot axis, all other things being equal, the two column wheels would then rotate in the counterclockwise direction.

[0022] Always referring to the figure 3 As can be seen, the leaf spring 47 is mounted on the control rocker 51. Indeed, when a pawl is positioned between the column wheel with which it cooperates and the pivot axis of the control rocker, it can be advantageous for the spring that returns the pawl against the column wheel to be mounted on the control rocker 51. Conversely, the leaf spring 27, which is arranged to cooperate with the pawl 25 that is returned against the part of the column wheel 15 located on the side opposite the axis 53, is mounted on the frame or on a bridge of the timepiece. Finally, it should be specified that, in accordance with this example, the column wheel 15 of the figure 3 and the column wheel 1 of the figure 1 are in fact the same column wheel. Furthermore, the column wheel 35 of the figure 3 and the column wheel 135 of the figure 2 are in fact one and the same column wheel as well.

[0023] It will also be understood that various modifications and / or improvements, obvious to a person skilled in the art, can be made to the embodiment described herein without departing from the scope of the present invention as defined by the appended claims. In particular, the control cams of the invention are not necessarily circular cycle cams like column wheels. Indeed, according to other embodiments, the control cams could, for example, be shuttle cams.

Claims

1. Control device for timepiece mechanisms, comprising: - two control cams (15, 35) each having drive means (17, 37) and arranged to be located, selectively, in a first and second plurality of predefined angular positions respectively; - a manual control mechanism having an outer control member and arranged to allow a user to simultaneously move the two control cams (15, 35) from one predefined angular position to another, so that cyclically the first and second plurality of predefined angular positions are taken up by the two control cams (15, 35) respectively; - at least two cam followers having first ends arranged to cooperate respectively with the two control cams (15, 35), the first ends of the two cam followers being arranged to each be located, depending upon the predefined positions taken up by the two control cams (15, 35), either bearing against a tip (19, 39) of one of the two control cams, or lowered into a trough thereof, each of the two cam followers further having a second end arranged to cooperate with a timepiece mechanism so as to switch said timepiece mechanism in one direction when the first end is lowered into a trough of one of the two control cams (15, 35) and in the other direction when it is raised to come to bear against a tip (19, 39) thereof, characterised in that the manual control mechanism has a control lever arm (51) arranged so as to be able to pivot about a spindle (53) and so as to be able to cooperate with the outer control member to move from a rest position to a tipped-over position when the user actuates the outer control member and to then return to the rest position when the outer member is released, and in that the manual control mechanism has first and second actuating means (25, 45) borne by two opposite ends of the control lever arm (51) and arranged to cooperate respectively with the drive means (17, 37) of the two control cams (15, 35) so as to drive the latter from one of the predefined angular positions to another.

2. Control device as claimed in claim 1, characterised in that the at least two cam followers are formed by levers.

3. Control device as claimed in claim 2, characterised in that the two control cams (15, 35) are formed by column-wheels each having columns (19, 39) and a ratchet (17, 37) formed of teeth, in that the columns (19, 39) form as many tips against which the first ends of the levers can come to bear, the empty spaces between the columns forming the troughs into which the first ends of the levers can be lowered, in that the drive means (17, 37) are formed by the ratchet, and in that the first and second actuating means (25, 45) are formed by two clicks articulated on the control lever arm (51).

4. Control device as claimed in claim 3, characterised in that a first (25) of the two clicks (25, 45) is arranged to increment the column wheel (15) with which it cooperates by pulling one tooth of its ratchet (17), and in that the second (45) of the two clicks is arranged to increment the column wheel (35) with which it cooperates by pushing one tooth of its ratchet (37).

5. Control device as claimed in claim 3 or 4, characterised in that one (45) of the two clicks (25, 45) is arranged between the pivot spindle (53) of the control lever arm (51) and the column wheel (35) with which said one (45) of the two clicks is arranged to cooperate, and in that the other column wheel (15) is arranged between the pivot spindle (53) of the control lever arm (51) and the other (25) of the two clicks.

6. Control device as claimed in claim 5, characterised in that the control lever arm (51) has an arm which connects the pivot spindle (53) to the end on which said one (45) of the two clicks (25, 45) is articulated, and in that the outer control member is arranged to push said arm when it is actuated by a user.

7. Control device as claimed in claim 4 and claim 5 or 6, characterised in that said one (45) of the two clicks is said second (45) of the two clicks, and in that the other (25) of the two clicks is said first (25) of the two clicks.

8. Control device as claimed in any one of claims 3 to 7, characterised in that it has two jumpers (21, 41) which are returned by two springs (23, 43) against the ratchets (17, 37) of the two column wheels (15, 35).

9. Control device as claimed in any one of claims 3 to 8, characterised in that it has two leaf springs (27, 47) which are arranged respectively to return the two clicks (25, 45) against the ratchets of the two column wheels (15, 35).

10. Control device as claimed in claims 5 and 9, characterised in that the leaf spring (47) which is arranged to return said one (45) of the two clicks against the ratchet (37) of the column wheel (35), with which it is arranged to cooperate, is mounted on the control lever arm (51).

11. Control device as claimed in claim 5 and claim 9 or 10, characterised in that the leaf spring (27) which is arranged to return said other (25) of the two clicks against the ratchet (17) of the column wheel (15), with which it is arranged to cooperate, is mounted on the frame.