CH720977A2 - Control organ for timepiece - Google Patents

Abstract

The invention relates to a control member intended to be placed on a watch case comprising a timepiece mechanism, said control member being intended to be connected to the timepiece mechanism, said control member comprising: – a head (16) for connecting the control member to the timepiece mechanism, and a cap (20) intended to be visible and to be handled by the user, – means for fixing the cap (20) on the head (16), said fixing means comprising a longitudinal locking element, for example a split ring (32), received simultaneously in a groove (30) of the head (16) and in a groove (34) of the cap (20), and elastic means, for example an elastic ring (42), exerting a force between the head (16) and the cap (20) tending to separate the head (16) and the cap (20).

Description

TECHNICAL FIELD AND PRIOR ART

[0001] The present invention relates to a control member for a timepiece, such as a winding crown, a pusher or a corrector, and to a timepiece comprising such a member.

[0002] A watch crown is generally located on the side of the watch case and mechanically cooperates with the mechanical watch movement which is housed in the watch case, for example to wind the barrel spring and/or to set the time. The crown is connected to the mechanical watch movement in a known manner. The crown is intended to be mounted on a tube fixed to the watch case and is intended to be grasped by the user of the watch to act on the mechanical movement.

[0003] Typically, the crown has a visible outer portion and an inner portion made of steel that serves to perform the function, such as adjustment, and also to attach to the winding stem. When both the inner portion and the outer portion are made of metal, the outer portion is most often driven onto the inner portion.

[0004] For some watch models, it is desired to make ceramic crowns. However, it is not possible to make the entire crown out of ceramic. To do this, the outer part of the crown is made out of ceramic and the inner part out of metal. However, a ceramic element cannot be driven onto a metal element. One solution implemented to assemble the outer part and the inner part is bonding.

[0005] There is an increasing desire to eliminate glue from assemblies.

STATEMENT OF THE INVENTION

[0006] It is therefore an aim of the present invention to provide a control member for a timepiece making it possible to dispense with the need for gluing for its assembly.

[0007] The above-mentioned aim is achieved by a control member comprising an inner part or head intended to be connected to a clockwork mechanism and an outer part or cap, the outer part being assembled to the inner part by an axial locking element and by an elastic element providing a restoring force which, in cooperation with the axial locking element, locks the outer part in position on the inner part.

[0008] Thanks to the invention, glue is eliminated during assembly. The invention makes it possible to assemble the head and the headdress simply and quickly regardless of the materials used.

[0009] In an exemplary embodiment, the axial locking element is a split ring and the elastic element is a ring made of elastic material.

[0010] In a preferred example, the control member comprises a ring to ensure the tensile strength of the assembly of the inner part on the outer part, an elastic ring, of the O-ring type, eliminating the axial play between the head and the cover, and at least one flat between the inner part and the outer part to ensure anti-rotation between the two parts.

[0011] In other words, the invention comprises means for fixing the cap to the head, said fixing means comprising at least one longitudinal locking element along the longitudinal axis cooperating at least with one transverse surface of the head or the cap and elastic means exerting a force between the head and the cap tending to separate the head and the cap from each other.

[0012] One of the objects of the present invention is then a control member intended to be placed on a watch case comprising a timepiece mechanism, said control member being intended to be connected to the timepiece mechanism, said longitudinal axis control member comprising a head intended for fixing the control member to the timepiece mechanism, and a cap intended to be visible and to be handled by the user, means for fixing the cap on the head, said fixing means comprising a longitudinal locking element along the longitudinal axis received simultaneously in a groove of the head and in a groove of the cap and elastic means exerting a force between the head and the cap tending to move the head and the cap apart from each other.

[0013] Preferably, the longitudinal locking element is a split ring.

[0014] The cap has for example a cup shape comprising a bottom and the elastic means are arranged between the bottom of the cap and the head.

[0015] Preferably, the elastic means comprise a ring made of elastically deformable material.

[0016] The control member advantageously comprises means configured to block rotation between the head and the cover around the longitudinal axis.

[0017] The head preferably comprises at least one flat on its outer lateral face and the cap comprises at least one flat on its inner lateral face cooperating with the flat of the head.

[0018] For example, the head has on its outer lateral face a shoulder extending radially, and the cap has on its inner lateral face a radial bearing surface, the shoulder being opposite the bearing surface and being arranged between the grooves and the elastic means.

[0019] Another object of the present invention is a timepiece comprising a watch case, a timepiece mechanism and a control member according to the invention, said control member being connected to the timepiece mechanism.

[0020] The clockwork mechanism may be provided with a winding stem and the control member may be a crown, the head being fixed to the winding stem.

[0021] The timepiece comprises, for example, a tube fixed to the watch case and surrounding the winding stem and in which the tube comprises at least one groove on its outer lateral face and a seal received in said groove, said seal ensuring sealing between the tube and the head.

[0022] Another object of the present invention is a method of assembling a control member according to the invention, comprising: – placing the blocking element in the groove of the head and maintaining it in a radially retracted state, – placing the elastic means in the cap, – inserting the head into the cap, – compressing the elastic means, – placing the groove of the head and the groove of the cap opposite each other and radially deploying the blocking element.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present application will be better understood with the aid of the description which follows and the appended drawings in which: – Figure 1 is a front view of an exemplary embodiment of a control member according to the invention, – Figure 2 is a longitudinal sectional view of the mechanism of Figure 1, – Figure 3 is an exploded view of Figure 1. – Figure 4 is a cross-sectional view along plane AA of the control member of Figure 1, – Figure 5 is a perspective view of a timepiece comprising an exemplary control member according to the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

[0024] In the following description, a proximal element designates an element located or oriented towards the watch case and a distal element designates an element located at a distance or oriented away from the watch case.

[0025] In the description which follows, the control member which will be described in detail is a crown, but it will be understood that the invention is not limited to crowns but the control member according to the invention can be, in a non-limiting manner, a pusher or a corrector.

[0026] In Figures 1 to 4, an example of embodiment of a crown 15 for a timepiece, for example a wristwatch 2, can be seen. In Figure 5, an example of a timepiece comprising such a crown 15 can be seen. The timepiece comprises a watch case 4, a dial, hands (not shown), a crystal 8 and a clockwork mechanism (not visible) located inside the watch case. In this example, the crown is received in a housing made in a side face of the watch case.

[0027] The crown 15 has the function of allowing action on the clockwork mechanism by manipulating the crown, for example to allow setting the time or winding the barrel spring of the clockwork mechanism, in the case of a mechanical watch.

[0028] In one exemplary embodiment, the crown can be moved along its longitudinal axis.

[0029] The crown 15 extends along the longitudinal axis Y which is orthogonal to the axis of the timepiece.

[0030] The crown is intended to cooperate with a tube 10 fixed to the watch case and crossed by the winding stem of the clockwork mechanism.

[0031] The tube 10 advantageously comprises, at its distal end, grooves 12 on its external lateral face receiving seals 14 cooperating with the head of the crown to ensure the sealing of the interior of the watch.

[0032] The crown 15 comprises a head 16 intended to be fixed to the winding stem (not shown) of the clock mechanism, and a cap 20 fixed on the head 16.

[0033] The head 16 comprises a body 21 of cylindrical shape of revolution. The body 21 has a cross-sectional shape open towards the tube 10 and comprises a barrel 22 of longitudinal axis Y fixed in the bottom of the body 21 and comprising an open proximal end 23.

[0034] The barrel 22 is received in the distal end of the tube 10.

[0035] The barrel 22 comprises, for example, a tapping intended to cooperate with the thread of the winding stem.

[0036] The cap 20 has an internal shape corresponding substantially to the external shape of the head 16 and having, in this example, teeth 24 on its external face.

[0037] Preferably, the head 16 and the cap 20 comprise means cooperating with each other to facilitate longitudinal guidance along the Y axis, when placing the cap 20 on the head 16 during assembly. In the example shown and advantageously, the head 16 comprises two flats 26 on its outer lateral face and the cap 20 comprises two flats 28 on its inner lateral face. In the example shown, the flats 26, 28 are diametrically opposed (FIG. 4).

[0038] Furthermore, the cooperation of the plates ensures anti-rotation between the head and the cover.

[0039] The head 16 has on its outer lateral face a groove 30 opening radially outwards receiving a split ring 32.

[0040] The cap 20 has a groove 34 in its inner lateral face intended to come opposite the groove 30. The dimensions of the rod and the outer diameter of the groove 34 are chosen so that once deployed, the rod extends partly into the groove 30 and partly into the groove 34.

[0041] In the example shown, the inner lateral face of the cap 20 comprises a radial bearing surface 36 intended to come into contact with a shoulder 38 of the outer lateral face of the head 16. In the example shown, the radial bearing surface 36 forms one of the longitudinal end faces of the groove 34.

[0042] The radial bearing surface 36 and the shoulder 38 provide a stopping function during assembly, forming a stop when inserting the head into the cap.

[0043] The crown 15 also comprises elastic means 40 interposed between the cap 20 and the head 16, so as to exert a force tending to separate the head 16 from the cap 20 in the longitudinal direction Y. In the example shown, the elastic means 40 comprise a ring 42 made of elastic material, for example elastomer, of the O-ring type, interposed between the bottom of the cap 20 and the distal end of the head 16. Preferably, the ring 42 has an external diameter substantially equal to the internal diameter of the cap 20. Advantageously, the edge 44 of the distal end of the head is beveled to serve as a support for the ring 42.

[0044] In Figure 2, the ring 42 can be seen in compression between the cap 20 and the head 16.

[0045] The assembly and immobilization of the headdress on the head is carried out in the following manner.

[0046] The split ring 32 is mounted in the groove 30 and is kept retracted inside the latter. The ring 42 is placed in the bottom of the cap 20.

[0047] Then the plates 26 of the head 16 are aligned with the plates 28 of the cap 20 and the head 16 is inserted into the cap 20 in the Y direction. The ring 32 is held in the groove 30.

[0048] The head 16 is inserted into the cap until the shoulder 38 comes to bear against the radial bearing surface of the cap 20.

[0049] From a certain penetration stroke of the head 16 into the cap 20, the ring 42 is compressed between the bottom of the cap 20 and the distal end of the head 16. This compression occurs while the groove 30 penetrates into the cap 20, and when it is opposite the groove 34. In this position, the ring 32 deploys radially. The ring 32 then extends both radially in the grooves 30 and 34.

[0050] The cooperation of the ring 32 with the distal edge 51 of the groove 30 ensures axial blocking of the cap 20 on the head 16, preventing the crown from being removed from the head. The elastic ring 42 exerts a force tending to move the cap away from the head.

[0051] The combined action of the ring 32 cooperating with the grooves 30 and 34, in particular with the edge 51, and of the elastic force exerted by the compressed ring 42 prevents any relative movement of the cap 20 and the head 16 along the axis Y in both directions, and absorbs the axial clearances.

[0052] An element other than a split ring can be implemented. For example, flexible blades provided with a beak at their free end can be machined directly in the head or the cap and cooperate with a transverse surface of the cap or the head respectively, which ensures a locking of the cap on the head along the Y direction. The flats ensure the locking in rotation about the Y axis between the head and the cap.

[0053] In the example shown, rotation between the cap 20 and the head 16 is prevented by the cooperation of the flats on the head and in the cap. Furthermore, the friction that exists between the ring 42 and the parts also makes it possible to absorb the rotational play. Alternatively, the anti-rotation function is ensured, for example, by the implementation of a pin or a snap ring.

[0054] Alternatively, the elastic means comprise a disk of elastic material, a helical spring or a leaf spring or any other means capable of exerting an elastic force tending to move the cap away from the inner part.

[0055] It will be understood that the invention applies to any crown comprising a head and a cap regardless of the internal structure of the head. For example, the seals may be carried by the internal surface of the crown. The shape of the barrel, the attachment of the head to the winding stem and the cooperation between the tube and the head may vary without departing from the scope of the present invention.

[0056] Thanks to the invention, the glue can be omitted in the assembly of the cap and the head.

[0057] The invention makes it possible to assemble a cap made of any material with a head made of any material. For example, the cap can be made of ceramic, precious metal such as gold, platinum and the head is for example made of stainless steel or precious metal.

[0058] The invention makes it possible to combine two parts requiring, for example, different treatments.

[0059] The invention also makes it possible to produce crowns with a very specific aesthetic without having to take into account the mechanical part which ensures the assembly of the crown with the winding stem. The addition of a groove inside the cap has no effect on its external appearance.

Claims (11)

1. Control member intended to be placed on a watch case comprising a watch mechanism, said control member being intended to be connected to the watch mechanism, said control member with a longitudinal axis (Y) comprising: – a head (16) intended for fixing the control member to the watch mechanism, and a cap (20) intended to be visible and to be handled by the user, – means for fixing the cap (20) on the head (16), said fixing means comprising a longitudinal locking element (32) along the longitudinal axis (Y) received simultaneously in a groove (30) of the head (16) and in a groove (34) of the cap (20) and elastic means (40) exerting a force between the head (16) and the cap (20) tending to separate the head (16) and the cap (20) from each other. 2. Control member according to claim 1, in which the longitudinal locking element (32) is a split ring. 3. Control member according to claim 1 or 2, in which the cap (20) has a cup shape comprising a bottom and in which the elastic means (40) are arranged between the bottom of the cap (20) and the head (16). 4. Control member according to claim 1, 2 or 3, in which the elastic means (40) comprise a ring (42) made of elastically deformable material. 5. Control member according to one of claims 1 to 4, comprising means configured to block rotation between the head and the cover around the longitudinal axis (Y). 6. Control member according to one of claims 1 to 5, in which the head (16) comprises at least one flat (26) on its outer lateral face and the cover (20) comprises at least one flat (28) on its inner lateral face cooperating with the flat (26) of the head (16). 7. Control member according to one of claims 1 to 6, in which the head (16) has on its outer lateral face a shoulder (38) extending radially, and the cap (20) has on its inner lateral face a radial bearing surface (36), the shoulder (38) being opposite the bearing surface (36) and being arranged between the grooves (30, 34) and the elastic means (40). 8. Timepiece comprising a watch case, a timepiece mechanism and a control member according to one of claims 1 to 7, said control member being connected to the timepiece mechanism. 9. Timepiece according to claim 8, in which the timepiece mechanism is provided with a winding stem and the control member is a crown and in which the head is fixed to the winding stem. 10. Timepiece according to claim 9, comprising a tube (10) fixed to the watch case and surrounding the winding stem and in which the tube comprises at least one groove (12) on its outer lateral face and a seal (14) received in said groove, said seal (14) ensuring the seal between the tube and the head. 11. Method for assembling a control member according to one of claims 1 to 7, comprising: – placing the locking element (32) in the groove of the head (16) and holding it in a radially retracted state, – placing the elastic means (40) in the cap (20), – inserting the head (16) into the cap (20), – compressing the elastic means (40), – placing the groove (30) of the head (16) and the groove (34) of the cap (20) opposite each other and radially deploying the locking element (32).