HK1168665B - Striking watch provided with a gong insulator - Google Patents

Description

Time-telling watch with gong isolator

Technical Field

The invention relates to a striking watch comprising at least one gong fixed to a gong-carrier, and at least one hammer for striking said gong.

Background

In the field of watchmaking, a movement is made with traditional architecture, said movement having a striking mechanism, such as a minute repeater. In such an embodiment, the gong or gongs used are each formed by a metal wire, substantially circular in shape and placed in parallel planes of the dial. The wire of each gong is arranged substantially around the movement, in the frame of the watch and above the plate on which the various parts of the movement are mounted. One end or more ends of each gong are fixed, for example by (soft) soldering, to a gong-carrier integral with the plate, for example common to all gongs. The other end of each gong may be substantially free.

The striking mechanism of the watch comprises at least one hammer actuated at a predetermined time. The gong vibrations are generated by the impact of the respective hammer on the gong in the vicinity of the gong-carrier. Each hammer is usually rotated partly in the plane of the gong so as to strike the corresponding gong and vibrate it in its plane. Part of the vibration of the gong is transmitted to the plate by the gong-carrier.

Depending on the shape and size of the gong used in the striking mechanism, after a sudden movement of the watch, an inadvertent ringing may occur in the rest mode, caused by the gong striking against the adjacent metal parts. The longer the length of a gong, for example a church gong comprising at least two windings around the movement of a watch, the more likely it is that problems of inadvertent ringing or accidental resonance occur. Materials with lower elastic moduli may also contribute to inadvertent ringing. This is a drawback of the luxury watch with this type of striking mechanism.

One solution to this problem is set forth in EP patent application No. 1914606A1. In this patent application, one or more mechanical noise isolators are provided for one or more gongs of the striking mechanism. The striking mechanism comprises two church gongs which are fixed via one end to a single gong carrier. The mechanical isolator is for example at least one separation member placed between the windings of the gong, except for the bells evenly distributed over each gong. However, a drawback of this isolator device is that there are a large number of stationary mechanical isolator elements in the watch case, which are located directly adjacent to each gong, which may cause interference in the strike mode of each gong. Moreover, this set of noise isolators for each gong greatly impairs the aesthetic appearance of such striking mechanisms.

Reference may also be made to DE patent No.443387, which discloses a locking device for a striking mechanism of an alarm watch. For this purpose, when the coil of the magnetic element is energized, said magnetic element holds the impact hammer in a tightening position at a distance from the gong. When the energization of the coil is interrupted, the hammer is released and can strike the gong. However, this does not prevent the gong from striking the adjacent metal parts when the striking mechanism is in rest mode, and is therefore a drawback.

It is also known from US patent No.2,054,765 to use magnetic elements in the striking mechanism, but said magnetic elements are only used for cooperating with the metal discs of said mechanism in order to adjust the speed of the striking mechanism, and not for providing gong isolation means.

Disclosure of Invention

It is therefore an object of the present invention to overcome the drawbacks of the prior art by providing a striking watch that uses a novel gong isolation principle to minimize the risk of inadvertent gong ring when the watch is subjected to shocks. The implementation of this novel gong isolation principle is relatively simple and allows the gong to vibrate freely in strike mode, while maintaining the aesthetic appearance of the striking mechanism.

The invention thus relates to the aforementioned striking watch, which incorporates the features defined in the independent claim 1.

Specific embodiments of the table are defined in the dependent claims 2-14.

One advantage of the striking watch according to the invention is that the gong is magnetically, rather than mechanically, isolated to prevent any inadvertent sounding of the gong when the watch is in rest mode. The presence of a magnetic gong-isolator device on the watch is original in the field of mechanical watches. This overcomes any existing prejudice which seeks to avoid the use of any magnetic element in a mechanical watch, since this would cause problems for the operation of said watch.

Drawings

Objects, advantages and features of a watch with a striking mechanism will become more apparent from the following description, particularly with reference to the accompanying drawings, in which:

figure 1 is a simplified top view of a first embodiment of the interior of a striking watch having a magnetic gong-isolator device according to the present invention,

figure 2a is a simplified top view of a second embodiment of the interior of a striking watch having a magnetic gong-isolator device according to the present invention,

FIG. 2b is an enlarged, fragmentary, radial cross-sectional view of the interior of a striking watch having a magnetic gong-isolator device in accordance with the present invention, taken along section A-A of FIG. 2a, an

FIG. 3 is an enlarged, fragmentary, radial cross-sectional view of a third embodiment of the interior of a striking watch having a magnetic gong isolator device in accordance with the present invention.

Detailed Description

In the following description, those components of the striking watch that are well known in the art will be described only briefly.

Fig. 1 is a top view of the interior of striking watch 1. The watch comprises a movement 10 of a known watch, said movement 10 being shown in the open part and being normally arranged on the plate 5. The movement of the watch is generally a mechanical movement. The plate 5 can be surrounded by a wall 6 to define a frame housing the movement of the watch. The wall 6 may also be an intermediate part of the watch.

Striking watch 1 mainly comprises a striking mechanism which may form part of a movement 10 of the watch. The striking mechanism comprises a gong 3 fixed at one end to a gong-carrier 2, said gong-carrier 2 being integral with said plate 5 or with the watch case. This first end of the gong is fixed by welding or is held locked between two helically screwed opposite portions of gong-carrier 2. The second end of gong 3 is generally free to move. Gong carrier 2 protrudes with respect to the bottom of plate 5 to hold the gong above the bottom of plate 5. Gong 3 is formed by a metal wire which partially surrounds movement 10 and extends substantially in a plane parallel to plate 5 and to the dial (not shown). The wire of gong 3 may define a portion of a circle having an angle, for example, between 180 ° or less and 360 °, but preferably close to 330 °.

The striking mechanism of said watch 1 also comprises a hammer 4, said hammer 4 being able to strike a portion of gong 3 when actuated, in particular in the vicinity of gong-carrier 2. The hammer may be actuated to indicate an alarm time or minute repeater. In this first embodiment, hammer 4 is pivotally mounted with respect to an axis perpendicular to the plane of gong 3. However, the hammer may also be actuated translationally in a direction perpendicular to the gong.

Magnetic gong-isolator device 20 is provided to prevent gong 3 from inadvertently coming into contact with one or more metal parts of the watch close to the gong when the watch is subjected to shocks. Such as a watch movement, a plate 5 or a part of the external part of a watch.

Said magnetic isolator means 20 essentially comprise at least one moving permanent magnet 21, said moving permanent magnet 21 being preferably arranged in the vicinity of the second free end of gong 3. Said moving permanent magnet 21 may be incorporated on the gong or be located in a recess formed in the gong. The permanent magnets may also be (soft) soldered to the free end portions of the gong. In this embodiment, the magnetic field of the moving permanent magnet is directed mainly towards the plane of the gong, with the south pole facing the centre of the surface and the north pole facing the outside of the surface. The moving permanent magnet 21 also forms an inertial mass for increasing the density of the partial sounds (partials) produced and for increasing the coefficient of mass of the gong.

The magnetic isolator device 20 also comprises a first magnetic element which is a first fixed permanent magnet 22 arranged in the wall 6 of the frame or intermediate part of the watch. The first fixed permanent magnet 22 is placed directly opposite the moving permanent magnet 21 and may have the same size. However, the magnetic field of the first fixed permanent magnet 22 and the magnetic field of the moving permanent magnet 21 have opposite polarities. The north pole of the fixed permanent magnet faces the center of the surface and the south pole of the fixed permanent magnet faces the outside of the surface. In these cases, the gong is kept at a distance from the wall due to the repulsion force between the two magnets 21 and 22.

If the watch is subjected to shocks, the closer the gong is to the wall 6, the more the repulsion between the two magnets 21 and 22 will be enhanced, the degree of enhancement being 4 times the distance by using local approximation. In this way, the gong is magnetically isolated, preventing any contact, in particular between the gong and said wall 6 of the frame, when the watch is suddenly moved. It should be noted that such permanent magnets can be made with dimensions of 1mm3 or less, producing a magnetic field of less than 1200 gauss. The gong may be spaced from the wall by a distance of less than 0.3 mm. Furthermore, the transverse cross-section of the gong may define a rectangle or, preferably, a disc having a diameter of less than 0.8 mm.

According to this first embodiment, said magnetic gong-isolator device 20 may also comprise a second magnetic element, which is a second fixed permanent magnet 23 arranged in one portion of movement 10 of the watch. The second permanent magnet 23 is disposed opposite to the moving permanent magnet 21 and has the same size as the permanent magnets 21 and 22. The three permanent magnets are preferably arranged on the same line towards the center of the watch. The magnetic field of the second fixed permanent magnet 23 has the opposite polarity to the magnetic field of the moving permanent magnet 21. The north pole of the second fixed permanent magnet faces the center of the surface and the south pole of the second fixed permanent magnet faces the outside of the surface. This also therefore keeps gong 3 at a distance from any adjacent part of movement 10 of the watch carrying said second fixed permanent magnet 23. If the watch is subjected to a shock as described above, the closer the gong moves towards the part carrying said second permanent magnet 23, the more the repulsion between the two magnets 21 and 23 will increase. This also ensures good magnetic isolation of the gong in the movement direction of the watch.

Of course, it is possible to envisage providing a plurality of mobile permanent magnets over the entire length of the gong, and a plurality of fixed permanent magnets in the watch, each of said fixed permanent magnets facing one of the mobile permanent magnets. The orientation of the moving permanent magnets and the orientation of the fixed permanent magnets can be varied along the wires of the gong, while still keeping the gong at a distance from any adjacent watch part when the watch is subjected to shocks.

It should also be noted that each fixed magnetic element may also be a coil that can be connected to a continuous current source to generate a magnetic field having a polarity opposite to that of the moving permanent magnet opposite to the coil. Each coil may also be arranged to be disconnected from the continuous current source in a conventional strike mode.

Depending on the type of metal material used to make gong 3, one or more moving permanent magnets 21 may be made directly by magnetizing one or more portions of the gong. Such materials must therefore be ferromagnetic (iron, nickel, steel or cobalt). It is even conceivable to magnetize the entire length of the wire of the gong completely.

Fig. 2a and 2b show a second embodiment of striking watch 1 with magnetic isolator device 20 for gong 3. For the sake of simplicity, fig. 2a does not show the hammer, the wall or intermediate part of the watch, and the movement 10 of the watch, but said movement 10 is shown in fig. 2 b.

In this second embodiment, it can be seen that the first end of gong 3 is fixed to a first gong-carrier 2 integral with plate 5, and the second end of gong 3 is fixed to a second gong-carrier 2 integral with plate 5. Of course, it is also conceivable to fix each gong carrier to the watch case. The wires of the gong form a winding, which in this second embodiment extends over a sector of approximately 270 °.

In this configuration, magnetic gong-isolator device 20 comprises a moving permanent magnet 21, preferably arranged in the middle portion of the gong. The magnetic field is oriented in a direction generally perpendicular to the chassis plate 5 with the south pole facing the face plate side and the north pole facing the chassis plate side. The magnetic isolator device 20 must therefore contain another fixed permanent magnet 24, said fixed permanent magnet 24 being preferably arranged in the plate 5 and opposite the moving permanent magnet 21. The polarity of the magnetic field of the fixed permanent magnet 24 is opposite to that of the magnetic field of the moving permanent magnet 21 so as to generate a repulsive force. The south pole of said fixed permanent magnet 24 thus faces the back of the watch case, while the north pole faces the dial.

As in the first embodiment, gong 3 may also have a plurality of moving permanent magnets and bottom plate 5 has a plurality of fixed permanent magnets, each of which is opposite to a corresponding moving permanent magnet. The wires of the gong may be made of ferromagnetic material. In these cases, permanent magnetization of the middle part of the gong can also be achieved, as shown in fig. 2a and 2 b. It is also conceivable to permanently magnetize the entire length of the wire.

Fig. 3 shows an enlarged partial radial cross-sectional view of a third embodiment of striking watch 1 with magnetic isolator device 20 for gong 3. In this third embodiment, the fixed permanent magnet is a magnetized ring 32, said magnetized ring 32 being arranged opposite and coaxial to the moving permanent magnet 31 of gong 3. As schematically shown in fig. 3, the magnetized ring 32 is fixed to the plate and to a portion of the movement. The magnetic poles on the outer periphery of the moving permanent magnet 31 are the same as the magnetic poles on the inner periphery of the magnetized ring. Thus, if the watch is subjected to shocks in any direction, gong 3 is held in a stable position at a distance from the inner periphery of magnetized ring 32, due to the effect of the repulsion forces generated by permanent magnets 31 and 32.

It is also possible to provide a plurality of magnetized rings coaxially with the gong 3 at a plurality of positions along its length. The entire length of the magnetizable wire of the gong may advantageously be permanently magnetized.

From the description just given, a person skilled in the art can devise many variants of a striking watch with a magnetic gong-isolator device without departing from the scope of the invention defined by the claims. The middle part of the gong may be fixed to a gong-carrier integral with said plate or middle part of the watch. The hammer may be mounted on the middle part of the watch. Instead of a moving permanent magnet mounted on the gong, a moving magnetic element may be provided, which may be another coil connected to a continuous current source for generating a magnetic field.

Claims (14)

1. Striking watch (1) comprising at least one gong (3) fixed to a gong carrier (2) and at least one hammer (4) for striking the gong, characterized in that it comprises magnetic gong-isolator means (20) for preventing any inadvertent contact between the gong and the adjacent parts (5, 6) of the watch, said device comprising at least one moving permanent magnet (21) arranged on one portion of the gong (3) at a distance from the gong carrier (2), and at least one magnetic element (22, 23, 24, 32) arranged on one portion (5, 6) of the watch close to the gong, the magnetic element is capable of generating a magnetic field having an opposite polarity to the polarity of the magnetic field of the moving permanent magnet facing the magnetic element.

2. Striking watch (1) according to claim 1, characterized in that said magnetic element is a fixed permanent magnet (22, 23, 24, 32).

3. Watch (1) according to claim 1, characterized in that said magnetic element is a coil connectable to a continuous current source to generate a magnetic field having an opposite polarity to the polarity of the magnetic field of said moving permanent magnet (21, 31).

4. Striking watch (1) according to claim 3, characterised in that the coil is arranged to be disconnected from the continuous current source when the watch is in striking mode.

5. Striking watch (1) according to claim 1, characterised in that said gong (3) defines at least a portion of a circle or a portion of a rectangle around a movement (10) of the watch, inside a case or frame (6) of said watch; and a first end of the gong (3) is fixed to the gong-carrier (2) and a second end is free to move, the moving permanent magnet (21) being provided on the second end of the gong.

6. Striking watch (1) according to claim 5, characterised in that said gong-carrier (2) is integral with a plate (5) on which the movement (10) of the watch is mounted; and the magnetic element is a fixed permanent magnet (24, 32) mounted on or in the plate (5).

7. Striking watch (1) according to claim 6, characterised in that said fixed permanent magnet (32) is in the form of a magnetised ring arranged opposite and coaxial to the moving permanent magnet of the gong, the magnetic poles on the outer periphery of said moving permanent magnet being identical to the magnetic poles on the inner periphery of said magnetised ring.

8. Striking watch (1) according to claim 1, characterised in that said gong (3) defines at least a portion of a circle or a portion of a rectangle around a movement (10) of the watch, inside a case or frame (6) of said watch; and a first end of said gong (3) is fixed to a first gong-carrier (2) and a second end of said gong is fixed to a second gong-carrier (2'); and the moving permanent magnet (21) is arranged in the middle part of the gong.

9. Striking watch (1) according to claim 8, characterised in that said gong-carrier (2) is integral with a plate (5) on which the movement (10) of the watch is mounted; and the magnetic element is a fixed permanent magnet (24) mounted on or in the panel.

10. Striking watch (1) according to claim 1, characterized in that it comprises a plurality of gongs (3) arranged one above the other and without any contact, each one end of which is fixed to the same gong-carrier (2) or to a plurality of corresponding gong-carriers; and said magnetic gong-isolator device (20) comprises moving permanent magnets (21) arranged on one portion of each gong at a distance from said gong-carrier, said moving permanent magnets facing each other and having opposite magnetic field polarities so as to generate a repulsive force.

11. Striking watch (1) according to claim 10, characterised in that said magnetic gong-isolator device (20) comprises at least one fixed permanent magnet (24) arranged on or in the plate (5) of the watch to which the gong-carrier is fixed, opposite the moving permanent magnet of the gong closest to the plate, and with opposite magnetic field polarity.

12. Striking watch (1) according to claim 1, characterised in that said mobile permanent magnet (21) is made of ferromagnetic gong material.

13. Striking watch (1) according to claim 12, characterised in that said mobile permanent magnet (21) is made over the entire length of the gong.

14. Striking watch (1) according to claim 1, characterised in that a plurality of moving permanent magnets (21, 31) are provided over the length of the gong; and a plurality of magnetic elements formed by fixed permanent magnets (22, 23, 24, 32) arranged on one or more portions (5, 6) of the watch, close to the gong, respectively opposite each moving permanent magnet and having opposite magnetic field polarity to each moving permanent magnet.