The present invention concerns an internal device for blocking push buttons of a timepiece, in particular a chronograph watch, in order to prevent un-wanted activation of said push-pieces and to improve watertightness.
Chronograph functions of chronograph watches are usually controlled by two push buttons located at 2-o'clock and 4-o'clock, that is at both sides of the watch crown used to wind and set the watch.
In diver's watches the push buttons must have a waterproofing system in order to prevent damages to the watch mechanism.
Standard push buttons are provided with a stem which slides in an opening of the case or of a tube integral to the case and they are forced in position by elastic means. In this push buttons the waterproofing system mainly consists of a set of rubber gaskets and o-rings arranged between the head and/or the stem of the button and the opening of the case. In this case the waterproofing performances depends on the number and the efficiency of the gaskets but, anyway no waterproof features can be granted when the button is being pushed. As it is obvious, a fortuitous pressure on the push button when under water, or even the pressure of the water itself, may cause activation of the push button with serious damages to the watch mechanism.
To prevent the above they are known screw-down buttons which provide a thread surface for blocking the button by means of a corresponding thread externally provided in the case, or other tube element integral to the case. When the button is screwed to the case the button is prevented from being pushed so that waterproof features are safe. The above blocking system has two main limits. First of all screw-down push buttons are complicated and big sized so that they involve relevant production costs and they have aesthetic limits that render them not suitable for classic chronograph watches. In addiction, each push button has to be independently screwed to be blocked.
Main object of the present invention is to propose a locking device for push buttons of a timepiece, in particular a chronograph watch, able to overcome the above limits of the conventional chronograph push buttons.
Further object of the present invention is to propose a locking device for push buttons of a chronograph watch apt to prevent fortuitous movement of the push buttons.
Another object of the present invention is to propose a locking device for push buttons suitable to be used in any kind of chronograph watch, and with push buttons of any size and shape.
The above objects are attained by an internal blocking device for push buttons of a timepiece comprising:
Advantageously said drive means are operated through the wind/set crown of said timepiece.
Preferably said wind/set crown is a screw down crown arranged so that when it is unscrewed to set the time said push buttons are unblocked and then blocked again when said wind/set crown is screwed again.
When operated through the wind/set crown the drive means comprises a pinion coaxial to the wind/set crown and operated by a rotary motion of the wind/set crown, said pinion transmitting movement to a rack-like portion of the sliding elements.
Advantageously the drive means comprises at least one driven gear interposed between said pinion and said rack-like portion of said sliding elements in order to reduce or improve the transmission ratio.
In a preferred embodiment the drive means comprises a conical gear engaging a mating internal conical gear of said pinion, a spring member housed inside said pinion for disengaging said bevel gear from said internal conical gear, said wind/set crown being provided with a portion shaped so as to transmit rotary motion to said conical gear.
Alternatively the drive means can be operated through the bezel of said timepiece.
In this last case the watchcase provides at least one slot made in its upper surface for receiving a pin fastened at one end to the bezel and at its opposite end to the sliding element.
Preferably, in order to have a watertight watchcase, a gasket, or two annular sealing elements are placed around said at least one slot between the bezel and the watchcase.
Advantageously the bezel is provided with a screw thread coupling with a corresponding screw thread of said watchcase.
Still advantageously the block members are hook-shaped members protruding from the sliding elements.
In most cases the push buttons to be blocked are in number of two placed at about 2-o'clock and 4-o'clock of the timepiece.
When the watchcase has internally a circular shape the said sliding element is advantageously an annular element.
The device of the invention clearly improve watertightness of timepieces as push buttons can be used only when necessary. In addiction, when under water, the push buttons cannot be activated by the water pressure. The blocking device of the invention blocks the push buttons from inside the watchcase and it can be operated from outside by using existing watch elements, that is the wind/set crown or the bezel. These last prevents overloading the external part of the watchcase with extra elements.
Furthermore the blocking device of the invention is very rapidly operated, both for blocking and for releasing the push buttons as it does not need to independently screw or unscrew each push button
The push buttons do not need to be screw down buttons so that the external shape and size of the push buttons can be freely designed
The above and more advantages of the device of the invention will be better understood by way of preferred embodiments examples, described in the following with reference to the accompanying drawings, in which:
Referring first to
As shown in
Referring to
Referring to
The bezel 60 could be safely fastened to the watchcase 30″ by providing a threaded surface in the inner portion of the bezel and a corresponding threaded surface in the upper surface of the watchcase 30″. Moreover, to assure watertightness of the watchcase 30″ gaskets or o-rings could be provided around or at sides of the slots 35, 36 to be pressed between the bezel 60 and watchcase 30″.
It is clear that further embodiments of the invention could be provided and many changes or modifications could be carried out on the blocking device of the invention.
The external button that operates the drive means which move the sliding element could be other than the wind/set crown 50. The wind/set crown 50 and the push-buttons 10, 20 can be of any shape and size and they could be provided with more gaskets and/or o-rings arranged in a conventional way to improve watertightness. In particular the wind/set crown 50 could be a screw down crown as well as a standard crown.
The drive means that operates the sliding element upon rotary motion of the crown could be simplified. For instance, the hexagonal end portion 51 of the crown 50 could be directly connected to a correspondent internal shape of the pinion 53.
Different drive means could be provided for driving the sliding element from outside the timepiece through an existing external member of the timepiece as well as through specifically intended members.
The collars 11, 21 and as a consequence the blocking members 41, 42 could have a different shape. The collars must be greater in size than the aperture of the watchcase that houses the push-button and they could have whatever shape suitable to press a gasket or an o-ring against the internal surface of the watchcase. The blocking members must have a shape allowing them to abut the collar thereof when the device is in the push-button blocking position. The blocking elements could also be provided with a slope surface for making easier them to engage the collars.
The sliding element has to be restrained in a way suitable to let it slide inside the watchcase with respect to the push-buttons to be blocked. The restraining means could be simply the shape of the sliding element together with the shape of the case, as shown in
These and more changes and modifications could be carried out on the device of the invention still keeping safe the above disclosed advantages and remaining within the ambit of protection of the following claims.
In fact, the above disclosure of specific embodiments is useful to understand the field and scope of the present invention, so that people skilled in the art is able to put it into practice by modifying and adapting the above disclosed embodiments; such modifications will be then considered as equivalent of the disclosed embodiments. The numbers and terminology used are to be intended merely for disclosure and for comprehending the scope of the invention and then they do not limit the invention.
Number | Date | Country | Kind |
---|---|---|---|
PI2009A000003 | Feb 2009 | IT | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/IB10/50733 | 2/18/2010 | WO | 00 | 7/25/2011 |