Two-piece cam for watches

Abstract

The present invention relates to a heart-shaped cam for integration into a watch, preferably a wristwatch, wherein the cam has a rotation axis (1.1.1) about which the cam (1) can perform a rotational movement, and a circumferential cam track (1.2.1) which is suitable for cooperation with a cam lever (2), wherein the cam lever (2) is suitable for being pressed against the circumferential cam track (1.2.1) of the cam (1) by means of an applied force. The cam (1) has a first cam component (1.1) which is fixedly connected to the said axis of rotation (1.1.1) of the cam (1), a second cam component (1.2) which carries the said circumferential cam track (1.2.1) of the cam (1), and at least one elastic element (1.3), wherein the first cam component (1.1) and the second cam component (1.2) are elastically coupled to each other by means of the at least one elastic element (1.3) such that the second cam component (1.2) is acted upon when the tip (1.2.2) the heart-shaped cam (1) by the cam lever (2), in which the actuating force exerted by the cam lever (2) from said tip (1.2.2) points to the axis of rotation (1.1.1) of the cam (1), can perform a rotation and / or a displacement relative to the first cam component (1.1) in order to avoid a quasi-static position of the cam lever (2) on the circumferential cam track (1.2.1). The invention also relates to a clock mechanism for controlling at least one function in a clock, which has such a cam, as well as a clock with a corresponding clock mechanism, preferably a wristwatch.

Description

Field of invention

[0001] The present invention relates to the field of watchmaking and concerns watch parts suitable for integration into watch mechanisms and watches. In particular, the present invention relates to cams used in watch mechanisms and watches, especially a heart-shaped cam, for example for resetting to zero. The present invention also relates to a mechanism for controlling the functions of a watch, in particular a chronograph mechanism, which includes such a cam, and to a watch equipped with such a mechanism. Background of the invention and prior art

[0002] In connection with watches that have a chronograph function or a similar function, watch experts are familiar with heart-shaped cams or cam discs that can interact with a so-called cam lever or heart lever to reset the chronograph hand to zero or to adjust another component. Generally, such heart-shaped cams, also simply referred to as "hearts" by experts, are used in a wide variety of watch mechanisms for their control, for example, for resetting to zero, especially in zero-reset mechanisms for chronograph or rattrapant watches, and for setting a time zone in world time watches. Such control mechanisms are also well known to experts.In these control mechanisms, the cam acts as a control element with a pivot axis around which it can rotate, and with an outer circumferential cam track designed to interact with the cam lever that follows the cam's circumferential track. The cam lever is designed to be pressed against the cam's circumferential track by an applied force. The contours of the heart-shaped cam and the cam lever generate a torque which, depending on their relative position, causes the heart-shaped cam to rotate, thus achieving the desired zero return or adjustment.

[0003] Watch experts are also aware that a quasi-static state can occur if the corner of the cam lever or heart lever meets the tip of the heart. It should be noted here that, in the following, the term "heart tip" or "tip" refers to a narrower and more or less pointed section on the front of the circumferential cam track of the heart-shaped cam or heart, which is radially furthest from the cam's axis of rotation. The term "flattening" refers to a wider, flattened and / or slightly wavy or shoulder-shaped section on the back of the heart's circumferential cam track, located opposite the axis of rotation, which is radially closest to the cam's axis of rotation and determines the zero-reset position. Bulges sometimes formed on this flattening are also called "heart breasts."Furthermore, the term "corner" will be used below to refer to a narrower and more or less pointed section at the free end of the cam lever or heart-shaped lever, which can act upon the circumferential cam track of the heart-shaped cam. In this "corner-on-point" position, the force exerted by the cam lever is directed from the aforementioned point of the cam to the cam's axis of rotation and therefore cannot exert any torque. Theoretically, this position should lead to a failure of the zero return or adjustment mechanism. However, in practice, such a failure does not occur frequently for several reasons: firstly, the bearings of the components involved have some play; secondly, these components are flexible, albeit minimally; and finally, the heart-shaped lever typically rebounds from the heart several times before coming into static contact with the cam or heart.These dynamic effects mean that the desired zero reset or setting is usually possible even if the aforementioned "corner-on-point" position occurs, and thus theoretically a quasi-static state.

[0004] However, firstly, the occurrence of such a quasi-static state cannot be entirely ruled out, and secondly, the above explanations presuppose that the cam or the heart, with its attached components, can be rotated extremely easily, so that the aforementioned dynamic effects can cause the heart to rotate out of its quasi-static position. This latter condition, however, is not met by all watch mechanisms. For example, a chronograph mechanism developed by the applicant differs fundamentally from conventional chronographs in that it features a common and linked zero reset for the seconds and minutes counters. This results in a comparatively slow zeroing movement of the two counters, which also presents disadvantages with regard to the zero reset.On the one hand, due to the slow and sluggish winding of the counters in the aforementioned chronograph mechanism, the zero reset may simply not begin in the "corner-to-point" position, thus making it impossible to zero the chronograph hand from this position. On the other hand, due to the sluggish winding of the counters and the gear ratio between them, greater force is required for the zero reset in this mechanism, which leads to wear in the form of impact marks from the heart lever on the heart contour, i.e., on the circumferential cam track of the cam.

[0005] To overcome the aforementioned difficulties, various approaches can be found in the prior art. For example, Swiss patent CH 716 686 discloses a heart-shaped cam which has a deformable element at the point on the cam's circumferential track where the actuating force pressing the cam lever against the cam points towards the cam's axis of rotation, in order to prevent accidental locking of the cam in this position. The deformable element can be designed as a lamella centrally located in a longitudinal slot extending radially to the axis of rotation, or as a lamella running parallel to a transverse slot extending along the circumference of the cam and located parallel behind the circumferential track, or as a region extending along the circumference of the cam and made of a deformable material.However, this solution requires the use of a lamella in the area of ​​the circumferential cam track and cannot prevent impact marks from the heart lever in case greater forces are required.

[0006] European patent EP 3 101 486 discloses a zero-reset mechanism using a position-indexed core. The mechanism comprises an axle supporting a wheel, the core being position-indexed angularly relative to this wheel. The core is radially floating relative to the axle and is returned to a neutral position relative to the axle by an elastically flexible element, the flexible element being dimensioned to dampen any shock exerted on the circumferential cam track of the core. The flexible element can consist of a spring inserted between the wheel and the core and / or a resilient plate integrated into the core. The mechanism can therefore be used to dampen shocks acting on the circumferential cam track, but is not designed to prevent the aforementioned quasi-static state in the "corner-to-tip" position.

[0007] European patent EP 2 362 277 discloses a time zone mechanism with two programmable memory wheels, each comprising a drive wheel and a heart, wherein the heart is movable relative to the wheel by pivoting between index positions belonging to the wheel, which are formed, for example, by 24 notches on the wheel's circumference. The heart can interact with the notches via a finger located near its tip and is radially returned to the index positions by elastic restoring means. The finger located near the heart's tip and radially returned to the index positions by elastic restoring means serves to set the time zone. This device allows adjustment of the angle between the wheel and the heart, but is not suitable for avoiding the quasi-static state mentioned above.

[0008] Patent US 5,280,460 discloses a heart for chronograph watches that has an asymmetrical shape and, in particular, an asymmetrical heart tip to prevent the chronograph mechanism from jamming, especially in the operating position where the heart lever meets the tip of the heart contour. However, this solution requires an asymmetrical shape of the cam, especially the heart tip.

[0009] Japanese patent JP S 5 493 761 also discloses a mechanism with a heart cam, the blockage of which, particularly in the operating position where the heart lever strikes the tip of the heart contour, is to be avoided. The solution disclosed in this document consists of an additional mechanism comprising an additional cam, for example square or polygonal, attached to the heart cam, and a leaf spring acting on this additional cam, which allows rotation of the heart in the aforementioned operating position. However, this solution requires an additional mechanism and cannot prevent impact marks from the heart lever if greater forces are required.

[0010] Mechanisms with a heart-shaped cam are also known in the prior art. The blockage of this cam, particularly in the operating position where the heart lever strikes the tip of the heart contour, is to be avoided by means of heart levers with elastic elements. For example, French patent FR 1 366 161 discloses a heart lever consisting of two parts articulated together and pre-tensioned against each other by a spring, whereby the lever can be either straight or angled. However, this solution requires a modified heart lever and also cannot prevent impact marks from the heart lever under higher forces.

[0011] It can therefore be stated that while the approaches known in the prior art can provide solutions for certain devices, these approaches are not suitable for every clock mechanism and there is still a need for improvement. Object of the invention

[0012] The aim of the present invention is therefore to realize a cam suitable for integration into a clock, in particular a heart-shaped cam, which is improved in such a way that it overcomes the aforementioned disadvantages of previously known cams. In this context, it is particularly important to provide a cam improved in such a way that, on the one hand, the desired zero reset or adjustment is possible even if the aforementioned "corner-to-point" position occurs, and thus theoretically a quasi-static state, and that, on the other hand, wear in the form of impact marks of the heart lever on the heart contour, i.e., on the circumferential cam track of the cam, is largely avoided. This should also be achieved in clock mechanisms that require greater impact forces of the cam lever on the cam.Furthermore, any distortion of the heart contour under static load should remain negligible or at least follow a pattern that is relatively easy to correct. Additionally, the improved cam or the associated clock mechanism should not require significantly more space. Finally, a cam according to the invention should be as versatile as possible, and the reliable operation of the associated clock mechanism should be guaranteed. Summary of the solution according to the invention

[0013] The present invention therefore has a heart-shaped cam as its object, which has the features mentioned in claim 1, wherein a cam according to the invention is distinguished from the prior art by the features mentioned in the characterizing part of claim 1.To achieve the aforementioned objectives, the invention is characterized in particular by the fact that the cam comprises a first cam component that is fixedly connected to the axis of rotation of the cam, a second cam component that carries the circumferential cam track of the cam, and at least one elastic element, wherein the first cam component and the second cam component are elastically coupled to one another by means of the at least one elastic element in such a way that, when the tip of the heart-shaped cam is acted upon by the cam lever, with the actuating force exerted by the cam lever pointing from said tip to the axis of rotation of the cam, the second cam component can perform a rotation and / or a displacement relative to the first cam component in order to avoid a quasi-static position of the cam lever on the circumferential cam track.This allows a desired zero reset or setting to be possible even if the aforementioned "corner-on-point" position occurs, and thus theoretically a quasi-static state.

[0014] In specific embodiments of a cam according to the invention, the first cam component and the second cam component of the cam each have distinctly corresponding boundary surfaces against which the cam components can abut each other depending on the operating state. These boundary surfaces can serve as an eccentrically mounted axis of rotation for rotation and / or as a guide rail for displacement of the second cam component, for force transmission, and / or for defining a preferred position between the first cam component and the second cam component.

[0015] In further specific embodiments, said at least one elastic element pre-tensions the second cam component into a preferred position relative to the first cam component and can be realized by means of spring arms and / or by means of a region made of a deformable material and / or with the aid of a deformable material.

[0016] In further embodiments, the first cam component, the second cam component and the said at least one elastic element of the cam can be made in one piece or from at least two parts.

[0017] In a further embodiment, the aforementioned second cam component can have a gap running parallel to the inner circumference of the cam track, which springs the circumferential cam track. This allows the cam or the core to be designed with greater flexibility in order to reduce impact marks.

[0018] The present invention also relates to a clock mechanism and a clock which have such a heart-shaped cam.

[0019] Further features and advantages of a cam according to the invention, or of a corresponding mechanism and an associated clock, will become apparent from the dependent claims and from the following description which explains the invention in detail by means of the accompanying illustrations. Brief description of the images

[0020] The accompanying illustrations represent several exemplary embodiments of a heart-shaped cam according to the present invention.

[0021] The Figure 1a is a perspective view of a first embodiment of a heart-shaped cam according to the invention, wherein the cam is shown in an assembled state on a chronograph wheel and in cooperation with a cam lever; the Figure 1bshows a top view of the heart-shaped cam, according to the Figure 1a , where the cam is shown enlarged to illustrate its structure; the Figure 1c shows a top view of the heart-shaped cam, the associated chronograph wheel, and the cam lever, according to the Figure 1a , with some parts, especially one in Figure 1a The safety disc, not shown for better understanding, is depicted in a transparent representation; Figure 1d gives a longitudinal section through the cam according to the invention as well as through the other parts according to Figures 1a and 1c along the in Figure 1c line II shown again.

[0022] Figures 2a and 2b show top views of a second embodiment of a heart-shaped cam according to the invention, wherein the cam in both Figures 2a and 2b is analogous to the Figure 1ais shown in its assembled state on a chronograph wheel and in conjunction with a cam lever, and wherein in the Figure 2a the second cam component of the heart-shaped cam is in its starting position in a "corner-to-point" position, while in the Figure 2b the second cam component of the heart-shaped cam is located in a displaced position, positioned at the eccentric pivot point in an "corner-to-tip" position.

[0023] Figures 3a to 3f show enlarged top-down views of the heart-shaped cam according to the Figure 1a schematically and exemplarily various steps of the movement sequence between the cam components of the cam according to the invention in a "corner-to-tip" position; in the Figure 3a The second cam component of the heart-shaped cam is located, as in Figure 2a , in its starting position in a "corner-to-point" position, while in the Figure 3bthe second cam component of the heart-shaped cam, as in Figure 2b , in a displaced position at the eccentric pivot point in a "corner-to-point" position, wherein in Figure 3b the starting position according to Figure 3a For comparison, the second cam component of the heart-shaped cam is shown with a dashed line; in figures 3c and 3d, the second cam component of the heart-shaped cam is in a displaced position and tilted to the right at the eccentric pivot point in a "corner-to-tip" position, whereby in Figure 3d the starting position according to Figure 3a For comparison, the second cam component of the heart-shaped cam is shown with a dashed line; in figures 3e and 3f, the second cam component of the heart-shaped cam is in a displaced position and tilted to the left at the eccentric pivot point in a "corner-to-point" position, whereby in Figure 3f the starting position according to Figure 3a for comparison, it is shown with a dashed line; Figure 3gFigure 3a to 3f shows a top view of the heart-shaped cam in its zero position, in which the free end of the cam lever rests against the flattened surface of the cam. Detailed description of the invention

[0024] The invention will now be described in detail below with the aid of the aforementioned illustrations in two of its embodiments. Further modifications and additional embodiments not shown in the illustrations will also be presented below. The heart-shaped cam according to the invention is shown here by way of example, particularly in connection with a chronograph mechanism, although such a heart-shaped cam can readily be used in any watch mechanism that utilizes a heart-shaped cam. The following description in connection with a chronograph mechanism therefore does not represent any limitation of the scope of application of the invention. Construction

[0025] The Figure 1a Figure 1 schematically and exemplarily shows a perspective view of a first embodiment of a heart-shaped cam according to the invention, wherein the cam 1 is shown in an assembled state on a chronograph wheel 3 and in cooperation with a cam lever 2. Figure 1bThis heart-shaped cam 1 is shown enlarged to illustrate its structure. Figures 1a and 1b show in detail that a heart-shaped cam according to the invention is suitable for integration into a watch, preferably a wristwatch, and has a pivot axis 1.1.1 about which the cam 1 can rotate. The cam 1 also has a circumferential cam track 1.2.1, which is suitable for interaction with a cam lever 2, wherein the cam lever 2 is suitable for being pressed against the circumferential cam track 1.2.1 of the cam 1 by means of an applied force. The cam 1 according to the invention is characterized in that it comprises a first cam component 1.1, which is fixedly connected to the said axis of rotation 1.1.1 of the cam 1, a second cam component 1.2, which carries the said circumferential cam track 1.2.1 of the cam 1, and at least one elastic element 1.3. The first cam component 1.1 and the second cam component 1.2.The two cam components 1.2 are elastically coupled to each other by means of at least one elastic element 1.3 in such a way that the second cam component 1.2, when the tip 1.2.2 of the heart-shaped cam 1 is acted upon by the cam lever 2, and the actuating force exerted by the cam lever 2 points from the said tip 1.2.2 to the axis of rotation 1.1.1 of the cam 1, can perform a rotation and / or a displacement relative to the first cam component 1.1, so that a quasi-static position of the cam lever 2 on the circumferential cam track 1.2.1 can be avoided even in the aforementioned "corner-on-tip" position between the cam 1 and the cam lever 2.

[0026] The core of the present invention therefore lies in the functionally two-part design of the heart-shaped cam, wherein the at least one elastic element 1.3 serves to elastically couple the first 1.1 and second cam components 1.2 in order to avoid a quasi-static position in the "corner-to-point" position. The following section will explain in more detail how this core of the invention can be implemented in various embodiments.

[0027] In general, the first cam component 1.1 is rigidly connected to both the aforementioned pivot axis 1.1.1 and the chronograph wheel 3, or, in the case of the integration of cam 1 into a watch mechanism other than a chronograph mechanism, to a corresponding component, as shown in the longitudinal section according to the Figure 1dAs can be seen, the second cam component 1.2 has an internal recess within which both the first cam component 1.1 and the at least one elastic element 1.3 are arranged. Therefore, the second cam component 1.2 preferably fully encompasses the first cam component 1.1, so that the circumference of the second cam component 1.2 forms the aforementioned circumferential cam track 1.2.1 of the cam 1. The shape of the internal recess in the second cam component 1.2 and the external shape of the first cam component 1.1 correspond significantly – taking into account the space required for the at least one elastic element 1.3 – but may have different configurations depending on the embodiment of the cam. The cam 1 or the said circumferential cam track 1.2.1 on the second cam component 1.2 can cooperate with a free end 2.2 of the cam lever 2, which is rotatably mounted about a cam lever pivot axis 2.1 and can be moved onto the cam 1 or its circumferential cam track 1 as required.2.1 can exert an actuating force, for example for resetting to zero in a chronograph mechanism or in a comparable watch mechanism, or more generally for adjusting a watch component in another watch mechanism, such as in world time zone mechanisms. Typically, the free end 2.2 of the cam lever 2 has a narrower and more or less pointed section 2.3, which, as already mentioned, is referred to here as the "corner". Since the design of the cam lever 2, the connection of the cam 1 to the chronograph wheel 3 or to a corresponding component, and, in general, the various control mechanisms in watches are well known to watch experts, these aspects will not be explained in further detail. The following description therefore primarily concerns the features of the heart-shaped cam according to the invention itself.

[0028] It should be noted that in a heart-shaped cam 1 according to the invention, the first cam component 1.1 and the second cam component 1.2 preferably each have distinctly corresponding boundary surfaces A, A', B, B', C, C', against which the cam components 1.1, 1.2 can abut each other depending on the operating state. These distinctly corresponding boundary surfaces A, A', B, B', C, C' are arranged on the outside of the first cam component 1.1, in the form of boundary surfaces A, B, C, and on the inner wall of the inner recess of the second cam component 1.2, in the form of boundary surfaces A', B', C'. The boundary surfaces A, A', B, B', C, C' are in Figure 1b , which shows the cam 1 in an enlarged representation, are most clearly recognizable and can be designed differently in different embodiments of the cam 1.

[0029] In the preferred embodiment of a heart-shaped cam 1 according to the invention, which is shown in Figures 1a to 1d and 3a to 3g, the first cam component 1.1 and the second cam component 1.2 each have three types of boundary surfaces A, A', B, B', C, C'. In this embodiment, the inner recess in the second cam component 1.2 preferably has a distinctly butterfly-like shape, wherein the first cam component 1.1 has a distinctly elongated shape and fills the body of the butterfly-like recess, while the at least one elastic element 1.3 is realized in the form of two elastic spring arms attached laterally to the first cam component 1.1, which each lie in the wing of the butterfly-like recess in the second cam component 1.2 or fill this wing space. In each case, a first type of boundary surface A, A' of the first cam component 1.1 and of the second cam component 1.2 at least partially and noticeably semicircular, wherein this semicircular section can advantageously be arranged at the rear end of the body of the aforementioned butterfly-shaped recess and encompassing the axis of rotation 1.1.1 of the cam 1. This first type of boundary surfaces A, A' of the first cam component 1.1 and the second cam component 1.2, in conjunction with the first cam component 1.1, serves as an axis of rotation 1.2.3, eccentrically arranged relative to the axis of rotation 1.1.1 of the cam 1, which is fixedly connected to the first cam component 1.1, for a rotation of the second cam component 1.2. This allows the second cam component 1.2 to be rotated, i.e., tilted, relative to the first cam component 1.1 by a predefined angle. The presence of the axis of rotation 1.2.3, which is eccentrically mounted to the axis of rotation 1.1.1 of the cam 1, thus creates the situation that the force exerted by the cam lever 2 is transferred from the tip 1.2.2 of the cam 1 to the axis of rotation 1.1.The problem of cam lever 2 not being directed towards cam 1 and therefore unable to exert a torque is resolved both theoretically and practically, since now not only is rotation of the entire cam 1 about the axis of rotation 1.1.1 possible, but also rotation of the second cam component 1.2 about the eccentrically mounted axis of rotation 1.2.3. Therefore, even when the aforementioned "corner-to-tip" position occurs between cam 1 and cam lever 2, a torque can be generated on cam 1 or on its circumferential cam track 1.2.1, thus avoiding a quasi-static position of cam lever 2 on cam 1 in the "corner-to-tip" position.

[0030] In this preferred embodiment, the first type of boundary surfaces A, A' of the first cam component 1.1 and the second cam component 1.2 has at least a partially straight section. With respect to the first cam component 1.1, this straight section A is advantageously arranged at a kind of neck extending from the noticeably semicircular section of the boundary surfaces A, A' and at the central body section of the butterfly-shaped recess. With respect to the second cam component 1.2, the straight section A' is arranged opposite the aforementioned neck of the first cam component 1.1 and its straight section A or boundary surfaces, also located at the central body section of the butterfly-shaped recess. Furthermore, the straight section of the first type of boundary surfaces A, A' of the first cam component 1.1 and the second cam component 1.2 is aligned with the connecting line between the tip 1.2.The second cam component 1.2 is aligned at an acute angle to the first cam component 1.1 and the axis of rotation 1.1.1 of cam 1, which is fixedly connected to the first cam component 1.1. This straight section can serve as a guide rail for moving the second cam component 1.2. This allows the second cam component 1.2 to be moved relative to the first cam component 1.1 by a predefined distance, so that the corner 2.3 of the cam lever 2 can slide off the tip 1.2.2 of cam 1. The presence of this guide rail, aligned at an acute angle to the aforementioned connecting line, also eliminates the situation where the force exerted by the cam lever 2 is directed from the tip 1.2.2 of cam 1 to the axis of rotation 1.1.1 of cam 1 and therefore cannot exert a torque.

[0031] In this preferred embodiment, the mobility of the second cam component 1.2 relative to the first cam component 1.1 therefore possesses two degrees of freedom in the form of rotation and translation. For this purpose, the first cam component 1.1 and the second cam component 1.2 each have corresponding clearance, i.e., a corresponding free space, between the aforementioned, noticeably corresponding boundary surfaces A, A', B, B', C, C' to allow the rotation and translation of the second cam component 1.2 relative to the first cam component 1.1, corresponding to the two degrees of freedom.

[0032] Furthermore, in this preferred embodiment, a second type of boundary surfaces B, B' serves for force transmission, and a third type of boundary surfaces C, C' serves to define a preferred position between the first cam component 1.1 and the second cam component 1.2. As shown, for example, in the Figure 1bAs can be seen, the boundary surfaces B, B', C, C' can be arranged on a widened extension of the aforementioned neck of the first cam component 1.1, directed radially outwards from the axis of rotation 1.1.1 of the cam 1, wherein this widened extension of the first cam component 1.1 fills the middle and the front body section of the said butterfly-shaped recess in the second cam component 1.2. With regard to the first cam component 1.1, the boundary surfaces C for defining the said preferred position are advantageously located on shoulders of the widened extension of the first cam component 1.1 that are directed in the direction of the axis of rotation 1.1.1 of the cam 1, while with regard to the second cam component 1.2, the boundary surfaces C', opposite the said shoulders C of the first cam component 1.1, are located on arcs of the second cam component 1.1 extending in the direction of the neck of the first cam component 1.1.2, which encompass the eccentrically mounted axis of rotation 1.2.3 formed by the semicircular boundary surfaces A of the first cam component 1.1, are arranged such that the boundary surfaces C, C' are also located in the central body section of the butterfly-shaped recess. The boundary surfaces B for force transmission between the first cam component 1.1 and the second cam component 1.2 are advantageously located laterally at the radially outwardly directed end of the widened extension of the first cam component 1.1 with respect to the first cam component 1.1, while with respect to the second cam component 1.2, the boundary surfaces B' are located on the lateral inner walls of the head end of the butterfly-shaped recess of the second cam component 1.2, opposite the aforementioned sides B of the outer end of the widened extension of the first cam component 1.1.2, which comprises the outer end of the widened extension, are arranged so that the boundary surfaces B, B' preferably lie in the front body section of the butterfly-shaped recess.

[0033] In the preferred embodiment shown in Figures 1a to 1d, the aforementioned at least one elastic element 1.3 pre-tensions the second cam component 1.2 into a preferred position relative to the first cam component 1.1. The at least one elastic element 1.3 is realized by means of spring arms attached between the first cam component 1.1 and the second cam component 1.2 of the cam 1, in particular in the form of the two elastic spring arms already mentioned above, attached laterally to the first cam component 1.1. Each of the two elastic spring arms 1.3 extends in an arc from the outside of the first cam component 1.1, with the elastic spring arms 1.3 extending into the wing space of the butterfly-shaped recess in the second cam component 1.2 and the free end of the elastic spring arms 1.3 bearing against the inner wall of the inner recess of the second cam component 1.2. The two elastic spring arms 1.3 exert a preload force on the second cam component 1.2 of the cam 1, which presses the boundary surfaces C, C' of the first cam component 1.1 and the second cam component 1.2 together.

[0034] In this preferred embodiment, as shown in Figures 1a and 1b, the second cam component 1.2 has a gap 1.2.4 running parallel to the inner circumference of the cam track 1.2.1, which cushions the circumference of the cam track 1.2.1. By appropriately designing this gap 1.2.4 and the thickness of the cam contour surrounding this gap 1.2.4, which forms the circumference of the cam track 1.2.1, the resulting cushioning of the dynamic impact of the cam lever 2 prevents or at least reduces wear on the cam 1 and its circumference of the cam track 1.2.1 in the form of impact marks from the cam lever 2 on the circumference of the cam track 1.2.1. This is particularly important in the case of the integration of a cam 1 according to the invention into a chronograph mechanism or a similar mechanism, in which the cam lever 2 is usually not in contact with the circumferential cam track 1.2 for extended periods of time.1 is not applied, but is only acted upon against the circumferential cam track 1.2.1 during short periods of time, which is why the cam lever 2 is also referred to as the heart lever or hammer in watchmaking circles, depending on the application.

[0035] Finally, it should be mentioned that, in the preferred embodiment, the first cam component 1.1 and the second cam component 1.2 of the cam 1 according to the invention are covered on the side opposite the chronograph wheel 3 by means of a retaining washer 1.5, as shown in Figures 1c and 1d. Preferably, the first cam component 1.1, which is attached to the pivot axis 1.1.1 of the cam 1, the retaining washer 1.5, and the chronograph wheel 3 are fixed to one another in a rotationally non-rotatable manner by means of pins 1.4, as shown by way of example in the Figure 1dAs shown, insofar as the first cam component 1.1 and the second cam component 1.2 of cam 1, as well as the intervening at least one elastic element 1.3, are secured in one direction by the chronograph wheel 3, or, in the case of integration of cam 1 into a watch mechanism other than a chronograph mechanism, by a corresponding component, and in the other direction by means of the retaining washer 1.5, the two cam components 1.1, 1.2 cannot perform any unintended tilting movement out of their plane. This ensures the reliable operation of the associated watch mechanism. Alternative solutions

[0036] The following section briefly explains several alternative solutions, mostly without explicitly showing these solutions in the illustrations.

[0037] In further embodiments of a heart-shaped cam 1 according to the invention, the first cam component 1.1 and the second cam component 1.2 of the cam 1 can, for example, have only one or, in all possible combinations, two of the aforementioned types of significantly corresponding boundary surfaces A, A', B, B', C, C', against which the cam components 1.1, 1.2 can abut each other depending on the operating state. Thus, the first cam component 1.1 and the second cam component 1.2 of the cam 1 can, for example, have only the first type of boundary surfaces A, A', which is at least partially semicircular and serves as the axis of rotation 1.2.3 of the second cam component 1.2, which is eccentrically mounted relative to the axis of rotation 1.1.1 of the cam 1, which is fixedly connected to the first cam component 1.1. In this less preferred embodiment, the second cam component 1.2 of the cam 1 can only perform a rotational or tilting movement relative to the first cam component 1.1.The first cam component 1.1 and the second cam component 1.2 of the cam 1 can, for example, only have the first type of boundary surfaces A, A', which is at least partially straight and serves as a guide rail for a displacement of the second cam component 1.2. In this less preferred embodiment, the second cam component 1.2 of the cam 1 can only perform a displacement movement relative to the first cam component 1.1. The first cam component 1.1 and the second cam component 1.2 of the cam 1 can also have several boundary surfaces A, A' of the first type, which are at least partially semicircular, so that, for example, in relation to the axis of rotation 1.1.1 of the cam 1 which is fixedly connected to the first cam component 1.1, two eccentrically arranged axes of rotation 1.2.3 of the second cam component 1.2 are defined, wherein one of the two axes of rotation 1.2.3 is for a tilting movement of the second cam component 1.2 to the right and the other of the two axes of rotation 1.2.3 is optimized for a tilting movement to the left. Analogously, this can be applied to several boundary surfaces A, A' of the first type, which are at least partially straight, in order to allow a displacement of the second cam component 1.2 to the right and a displacement to the left. In both cases, this can also be achieved by adding a third cam component (not shown in the figures) and corresponding additional elastic elements. For example, the first cam component 1.1 can be coupled to the said third cam component by means of the at least one elastic element 1.3, and the latter can be coupled to the second cam component 1.2 by means of at least one further elastic element, so that in this embodiment the first cam component 1.1 and the second cam component 1.2 are indirectly coupled via the third cam component by means of the at least one elastic element 1.3 are elastically coupled to one another. As a further alternative, the first cam component 1.1 and the second cam component 1.2 of the cam 1 can have only the second type of boundary surfaces B, B' for force transmission and / or only the third type of boundary surfaces C, C' for defining a preferred position between the first cam component 1.1 and the second cam component 1.2. In further, also less preferred embodiments of a heart-shaped cam 1 according to the invention, the first cam component 1.1 and the second cam component 1.2 of the cam 1 can have none of the aforementioned, each significantly corresponding, boundary surfaces A, A', B, B', C, C'. In these cases, the said at least one elastic element 1.3 must be designed such that it performs the functions of the said boundary surfaces A, A', B, B', C, C', i.e.The definition of the degrees of freedom rotation and / or translation, as well as the force transmission and the definition of a preferred position between the first cam component 1.1 and the second cam component 1.2, is carried out. With regard to the boundary surfaces A, A', however, it should be noted that – as mentioned above – one of the degrees of freedom rotation and / or translation is sufficient to realize the core of the present invention, whereby these degrees of freedom can be defined either by means of the respective corresponding boundary surfaces A, A', or by means of the at least one elastic element 1.3, or by means of both the boundary surfaces A, A' and the elastic element 1.3.

[0038] Furthermore, it should be generally mentioned that the shape of the first cam component 1.1, the recess of the second cam component 1.2 and accordingly the boundary surfaces A, A', B, B', C, C' can be designed in a variety of ways, so that a complete description of all possible embodiments is impossible without limiting the subject matter of the invention.

[0039] The at least one elastic element 1.3 can also be implemented by means of only one or alternatively by means of several, i.e., more than two, spring arms attached between the first cam component 1.1 and the second cam component 1.2 of the cam 1. In particular, the elastic spring arms 1.3 can also be attached to the second cam component 1.1 or to both the first cam component 1.1 and the second cam component 1.2, instead of merely resting against one of these parts.

[0040] In further embodiments of a heart-shaped cam 1 according to the invention, the said at least one elastic element 1.3 can also be realized by means of a region extending between the first cam component 1.1 and the second cam component 1.2 of the cam 1 made of a deformable material, for example an elastomer, and / or with the aid of such a deformable material that fills the regions between the first cam component 1.1, the second cam component 1.2 and the said at least one elastic element 1.3 of the cam 1.

[0041] It should also be noted that a heart-shaped cam 1 according to the invention does not necessarily have a gap 1.2.4 running parallel to the circumferential cam track 1.2.1 in the second cam component 1.2, which springs the circumferential cam track 1.2.1. An embodiment of a heart-shaped cam 1 according to the invention without such a gap 1.2.4 is shown in Figures 2a and 2b, wherein in the Figure 2a the second cam component 1.2 of the heart-shaped cam 1 is in its starting position in an "corner-to-point" position, while in the Figure 2bThe second cam component 1.2 of the heart-shaped cam 1 is located in a displaced position, aligned with the eccentric pivot point 1.2.3 in a "corner-to-point" position. The gap 1.2.4 is therefore optional and is only provided if, for specific reasons, the wear of the cam 1 in the form of impact marks from the cam lever 2 on the circumferential cam track 1.2.1 is high during operation of the associated watch mechanism and should therefore be avoided or at least reduced. This is the case, for example, with the chronograph mechanism developed by the applicant, which has a common and linked zero reset for the seconds and minutes counters, as this mechanism requires greater impact forces for the zero reset. How it works

[0042] Figures 3a to 3g will now be used to explain the functioning of the heart-shaped cam according to the invention or of a clock mechanism with such a cam.

[0043] From the above, it is clear that the at least one elastic element 1.3, i.e., in the preferred embodiment shown in Figures 3a to 3g, by the two spring arms 1.3, keeps the second cam component 1.2 in its preferred position during the normal operation of a chronograph mechanism equipped with this cam, which is in Figure 3aThe second cam component 1.2 is held in the position shown. In the preferred embodiment, the boundary surfaces C and C' are in contact with each other, since the second cam component 1.2 is neither displaced nor rotated relative to the first cam component 1.1. This is important to prevent the cam lever 2, i.e., in the case of a chronograph mechanism, the heart lever or hammer, from encountering an already tilted cam 1 or heart, which could create an "edge-to-point" position in which the second cam component 1.2 of the heart 1 would have already exhausted its evasive maneuvers provided by the aforementioned degrees of freedom of rotation and / or translation.

[0044] During normal operation of a chronograph mechanism equipped with a cam according to the invention or a comparable watch mechanism, the second cam component 1.2 remains in its preferred position, which is the one described in Figure 3aThe starting position shown corresponds to the occurrence of a "corner-to-point" position. However, if the position shown in the Figure 3a In the depicted "corner-on-tip" position, where the corner 2.3 of the cam lever 2 or the heart lever strikes the tip 1.2.2 of the heart 1 and acts upon it, the second cam component 1.2 can move slightly by displacement and rotation until the boundary surfaces A, A' touch, the semicircular sections of which simultaneously serve as the eccentric pivot point 1.2.3. In the Figure 3bThe figure shows the state in which the second cam component 1.2 is initially displaced relative to the first cam component 1.1 in the direction of the eccentric axis of rotation 1.2.3. The preferred position of the second cam component 1.2, i.e., its initial position, is indicated by dashed lines, and the displacement is symbolized by a straight arrow. This eccentric pivot point 1.2.3 now allows the second cam component 1.2 to rotate under the influence of the actuating force exerted by the cam lever 2 or the cam lever, i.e., to tilt relative to the first cam component 1.1. This state is illustrated in Figures 3c and 3d for a tilting movement to the right and in Figures 3e and 3f for a tilting movement to the left, where the second cam component 1.2 is shown in these figures after its displacement in the direction of the eccentric axis of rotation 1.2.3. A tilting movement to the right or left relative to the first cam component 1.1 about the eccentric axis of rotation 1.2.3 has been completed. It is not predictable whether the tilting movement will be to the right or left, but both lead to the same result. The aforementioned preferred position of the second cam component 1.2, i.e., its initial position, is again shown in Figures 3d and 3f using dashed lines, and the displacement as well as the rotation or tilting movement of the second cam component 1.2 is symbolized by a straight arrow and a curved arrow, respectively. By tilting the second cam component 1.2 relative to the first cam component 1.1, the corner 2.3 of the cam lever 2 or the heart lever can, in the further course of operation of such a clock mechanism, finally and safely slide away from the tip 1.2.2 onto one of the two flanks of the circumferential cam track 1.2.1 of the cam 1 or the heart.This clarifies the "corner-to-point" position, as the cam lever 2, or heart lever, now generates a torque in the conventional manner, thus rotating the cam 1, or heart, into the zero position. During this further operating sequence, the limiting surfaces B, B' of the first cam component 1.1 and the second cam component 1.2 come into contact with each other, so that the force transmission generated by these limiting surfaces B, B' transfers the rotational movement of the cam 1, initiated by the cam lever 2, or heart lever, to the chronograph wheel 3 and thus to the associated counter(s), thereby initiating the zeroing of the counter(s). As the zeroing progresses during the further operation of such a clock mechanism, the cam lever 2, or heart lever, reaches the area near the heart-shaped protrusions 1.2.5 on the circumferential cam track 1.2, as indicated in Figures 3c and 3e.1 of cam 1 the area in which the sum of the acting forces returns the second cam component 1.2 of cam 1 or of the heart back to the preferred position, i.e. into the position in . Figure 3a The starting position shown, relative to the first cam component 1.1, pushes and tilts. Upon reaching the zero position of cam 1, which is in Figure 3g As depicted, the boundary surfaces C' of the second cam component 1.2 are pressed again against the corresponding boundary surfaces C of the first cam component 1.1, thereby repeatedly assuming a defined preferred position of the second cam component 1.2 relative to the first cam component 1.1, and thereby returning the second cam component 1.2 to its position as shown in the Figure 3aThe starting position is shown. This process can be applied analogously to any comparable clock mechanism that uses such a heart-shaped cam 1, whereby, as mentioned, the functions of the boundary surfaces may be at least partially taken over by the at least one elastic element 1.3. In view of the alternative solutions described above, it is easy to understand that the above-described function can also be achieved mechanically by means of a rotation or a displacement of the second cam component 1.2 relative to the first cam component 1.1, although this is less preferred. In the design according to the invention, the spring-loaded outer contour of the second cam component 1.2 serves solely to cushion the dynamic impact of the cam lever 2 or the heart lever and allows only a negligible deviation from the ideal heart contour when the heart lever is in static contact.A heart-shaped cam according to the invention therefore allows in an elegant way to avoid a quasi-static position of the cam lever 2 on the circumferential cam track 1.2.1 when an "corner-to-point" position occurs. Material and manufacturing

[0045] In the preferred embodiment described above, the first cam component 1.1, the second cam component 1.2, and the aforementioned at least one elastic element 1.3 of the cam 1 are manufactured from at least two parts and are then attached to the axis of rotation 1.1.1 or to each other, as necessary, for example by press-fitting. Alternatively, the first cam component 1.1, the second cam component 1.2, and the aforementioned at least one elastic element 1.3 of the cam 1 can also be manufactured as a single piece.

[0046] Cam 1 and its components can be manufactured using various production methods common in watchmaking, such as forming, milling, laser or waterjet cutting, electrical discharge machining (EDM), deep reactive ion etching (DRIE), LiGA (lithography-electroplating), or 3D printing. Cam 1 and its components can be made from materials such as steel, sheet steel, various metallic alloys, and generally all metallic materials, plastics, ceramics, and single crystals with elastic properties. Applications

[0047] It is also clear from the foregoing that the present invention is directed in particular to a clock mechanism for controlling at least one function in a clock, which has a heart-shaped cam according to the invention, and to a clock with a corresponding clock mechanism, preferably a wristwatch.

[0048] Such a watch mechanism can consist in particular of a chronograph mechanism, a rattrapant mechanism, a time zone setting mechanism, an alarm mechanism, a calendar mechanism and generally of any watch mechanism with a rotating part which is to be brought into a specific position when required and repeatably. Advantages

[0049] In summary, the solution described above represents a functionally two-part cam whose two components are elastically pre-tensioned against each other, with the cam optionally featuring a spring-loaded heart-shaped contour. This allows for a desired zero reset or setting in a clock mechanism even if a "corner-to-tip" position occurs between the tip of the cam and the corner of the cam lever, theoretically resulting in a quasi-static state. Furthermore, it largely prevents wear in the form of impact marks from the heart lever on the heart-shaped contour, i.e., on the circumferential cam track of the cam. This solution is particularly advantageous in clock mechanisms that require higher impact forces from the cam lever on the cam.Furthermore, the cam according to the invention ensures that any distortion of the heart contour under static load remains negligible or at least follows a pattern that is relatively easy to correct. This cam, or the associated clock mechanism, also does not require significantly more space compared to conventional cams, since the proposed solution optionally requires only one additional retaining washer. Moreover, a cam according to the invention can be flexibly adapted to specific applications and associated requirements by appropriately selecting from the available alternative embodiments, and is therefore highly versatile, for example in chronograph, rattrapant, or similar clock mechanisms. Finally, a cam according to the invention ensures the reliable operation of the associated clock mechanism. List of reference symbols

[0050] Nr. element 1 heart-shaped cam 1.1 first cam component 1.1.1 Cam axis of rotation 1.2 second cam component 1.2.1 Circumferential cam track 1.2.2 Cam tip 1.2.3 eccentric axis of rotation of the second cam component 1.2.4 gap 1.2.5 Heart-shaped cam 1.3 elastic element 1.4 Pen 1.5 locking washer 2 cam lever 2.1 Axis of rotation of the cam lever 2.2 free end of the cam lever 2.3 Corner at the free end of the cam lever 3 Chronograph wheel or similar watch part A, A' Bounding surfaces for rotation and / or translation B, B' Boundary surfaces for force transmission C, C' Boundary areas for defining a preferred position

Claims

1. Heart-shaped cam for integration into a watch, preferably a wristwatch, wherein the cam has a rotation axis (1.1.1) about which the cam (1) can perform a rotational movement, and a circumferential cam track (1.2.1) suitable for cooperation with a cam lever (2), wherein the cam lever (2) is suitable for being pressed against the circumferential cam track (1.2.1) of the cam (1) by means of an applied force. characterized by the fact thatThe cam (1) comprises a first cam component (1.1) that is rigidly connected to the said axis of rotation (1.1.1) of the cam (1), a second cam component (1.2) that carries the said circumferential cam track (1.2.1) of the cam (1), and has at least one elastic element (1.3), wherein the first cam component (1.1) and the second cam component (1.2) are elastically coupled to each other by means of the at least one elastic element (1.3) such that the second cam component (1.2) undergoes a rotation and / or a displacement relative to the first cam component when the tip (1.2.2) of the heart-shaped cam (1) is acted upon by the cam lever (2), whereby the actuating force exerted by the cam lever (2) is directed from the said tip (1.2.2) to the axis of rotation (1.1.1) of the cam (1). (1.1) can be executed to avoid a quasi-static position of the cam lever (2) on the circumferential cam track (1.2.1).

2. Cam according to the preceding claim, characterized by the fact thatThe first cam component (1.1) and the second cam component (1.2) of the cam (1) each have distinctly corresponding boundary surfaces (A, A', B, B', C, C') on which the cam components (1.1, 1.2) can abut each other depending on the operating state.

3. Cam according to the preceding claim, characterized by the fact thatone of the boundary surfaces (A, A') of the first cam component (1.1) and the second cam component (1.2) is at least partially semicircular and serves as an eccentrically mounted axis of rotation (1.2.3) of the second cam component (1.2) relative to the axis of rotation (1.1.1) of the cam (1) which is fixedly connected to the first cam component (1.1), and / or one of the boundary surfaces (A, A') of the first cam component (1.1) and the second cam component (1.2) is at least partially straight and serves as an acutely angled guide rail for displacement of the second cam component (1.2) relative to the connecting line between the tip (1.2.2) of the cam (1) and the axis of rotation (1.1.1) of the cam (1) which is fixedly connected to the first cam component (1.1).

4. Cam according to one of the preceding claims 2 to 3, characterized by the fact thatin each case at least one of the boundary surfaces (B, B', C, C') serves for force transmission and / or for defining a preferred position between the first cam component (1.1) and the second cam component (1.2).

5. Cam according to the preceding claim, characterized by the fact that that said at least one elastic element (1.3) pre-tensions the second cam component (1.2) into a preferred position relative to the first cam component (1.1).

6. Cam according to one of the preceding claims, characterized by the fact that that said at least one elastic element (1.3) is realized by means of spring arms attached between the first cam component (1.1) and the second cam component (1.2) of the cam (1).

7. Cam according to one of the preceding claims, characterized by the fact thatthe said at least one elastic element (1.3) is realized by means of a region extending between the first cam component (1.1) and the second cam component (1.2) of the cam (1) made of a deformable material and / or with the aid of a deformable material that fills the regions between the first cam component (1.1), the second cam component (1.2) and the said at least one elastic element (1.3) of the cam (1).

8. Cam according to one of the preceding claims, characterized by the fact that the first cam component (1.1), the second cam component (1.2) and the said at least one elastic element (1.3) of the cam (1) are manufactured in one piece.

9. Cam according to any one of the preceding claims 1 to 7, characterized by the fact that the first cam component (1.1), the second cam component (1.2) and the said at least one elastic element (1.3) of the cam (1) are made of at least two parts.

10. Cam according to one of the preceding claims, characterized by the fact that The said second cam component (1.2) has a gap (1.2.4) running parallel along the circumferential cam track (1.2.1) on the inside, which springs the circumferential cam track (1.2.1) in order to avoid or at least reduce the wear of the cam (1) in the form of impact marks of the cam lever (2) on the circumferential cam track (1.2.1) by cushioning the dynamic impact of the cam lever (2).

11. Cam according to one of the preceding claims, characterized by the fact that the cam (1) is manufactured using a manufacturing process from the group comprising forming, milling, laser or water jet cutting, EDM, DRIE process, LiGA process, 3D printing process.

12. Cam according to one of the preceding claims, characterized by the fact thatthe components of the cam (1) are made of a material from the group containing steel, sheet steel, metallic alloys and materials, plastics, ceramics and single crystals with elastic properties.

13. Clock mechanism for controlling at least one function in a clock, preferably in a wristwatch, characterized by the fact that the clock mechanism has a heart-shaped cam (1) according to one of the preceding claims.

14. Clock mechanism according to the preceding claim, characterized by the fact that The mechanism is a chronograph mechanism, a rattrapant mechanism, a time zone setting mechanism, a clock mechanism, an alarm mechanism, a calendar mechanism. 3 p.m., preferably a wristwatch, characterized by the fact that the watch has a heart-shaped cam (1) according to any one of the preceding claims 1 to 12 and / or a watch mechanism according to any one of the preceding claims 13 to 14.

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