Mysterious rotating bezel

Description

BACKGROUND OF THE INVENTION

The present invention concerns a rotating bezel particularly for a timepiece such as a wristwatch, a clock or an alarm clock with a mechanical or electronic movement. This rotating bezel can be termed “mysterious” in that the orientation of the indications carried by the bezel, such as alphanumerical signs, always remain the same, i.e. these indications are always legible in the same direction as the indications marked on the dial whatever the rotational angle imparted to the bezel.

In all the currently known wristwatches with a rotating bezel, for example diving watches, the indications are marked on the bezel in radial directions such that it is possible to read them properly only when an indication is brought to the 12 o'clock position, with the obvious risk of the figures

6

and

9

being confused at the moment of selection. A watch of this type, with the figures from

1

to

12

being the indications carried by the bezel, is shown in FIG.

1

.

However, there exists a Japanese Patent No. JP 2599334, which attempts to provide a solution to the aforementioned problem. In the proposed device, the principle of which is shown in

FIG. 2

, the indications are carried by studs that are rotationally mobile in housings of the bezel, each stud having at its base a stem that is offset with respect to the axis of the stud. The stem is engaged in a circular groove of the same diameter as the circle described by the rotational axis of the studs, but whose centre is offset with respect to the centre of the dial by a distance equal to the distance between the rotational axis of each stud and the stem. For a rotation less than 180°, the indications maintain a vertical reading position. The 180° position (at 6 o'clock here) corresponds to an unstable position in which either a blockage can occur, which was observed by the inventors of the present invention, or rotation can continue beyond 180 ° still maintaining the vertical position, but also with the risk of creating a tipping movement causing the stems of two successive studs to come closer together as shown in

FIG. 2

, a the 5 o'clock position. In order to overcome this drawback, the author proposes placing a washer at the base of the studs, through which the stems of the studs pass at regular intervals, said washer being driven in rotation at the same time as the bezel. This solution, which requires the use of an additional part, theoretically allows the desired object to be attained but, because of the contact surface of the washer on the edges of the groove, has the major drawback of considerably increasing friction, to such a point that no product known to the Applicant includes such a device.

SUMMARY OF THE INVENTION

The present invention provides a different solution, allowing the drawbacks of the aforecited prior art to be overcome by providing a rotating bezel having a reduced number of parts to be assembled, and allowing the bezel to rotate freely, while still keeping the indications borne by the latter legible in the same direction.

The invention therefore concerns a rotating bezel comprising a ring able to rotate freely on a base in order to bring a selected indication opposite a determined mark of the base or a dial located at the centre of the bezel. The indications, alphanumerical characters, pictograms or other elements, are not directly marked on the ring but on the outer surface of studs that are each able to rotate freely about their axis of revolution in a housing arranged through the thickness of the ring and opening onto the base. Each stud includes on its lower part at least two stems of different dimensions, offset by the same distance from the axis of revolution of the studs, and having an angular offset less than 180°. When the bezel is driven in rotation, each stem is guided by a circular groove formed in the base and having a cross-section adapted to the dimensions of each stem, a radius equal to that of-the circle described by the axis of revolution of the studs, the centres of each groove having, with respect to the centre of the dial, exactly the same arrangement as the stems with respect to the axis of revolution of the studs.

When the studs include only two stems, the stems must not be aligned on the same diameter, otherwise there would still be the risk, as in the aforecited prior art, of an unstable position in which the rotation of the bezel could be blocked, or beyond which a reversion of the rotational direction of the studs in their housing could occur. With the proposed construction, the grooves necessarily intersect and, in a way, create switches. According to the invention, in order for each stem to recognise the direction to take in a switch, the stems of each stud and correlatively the cross-sections of the grooves, have different dimensions, either in length, or in diameter, or both in length and diameter. Although each stud can only include two stems, tests have shown that the most satisfactory result is obtained with studs including three studs offset angularly by 120° and differentiated both by their length and their diameter.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the invention will appear during the following description, given solely by way of example, and made with reference to the annexed drawings, in which:

FIG. 1

shows a top view of a wristwatch having a rotating bezel according to the prior art;

FIG. 2

shows the mechanism of another wristwatch with a rotating bezel according to the prior art;

FIGS. 3 and 3

b

is show top views of a wristwatch with a rotating bezel according to the invention in two different positions;

FIG. 4

shows the mechanism of the rotating bezel according to the invention;

FIG. 5

is a perspective diagram, seen from below, of a stud of the rotating bezel; and

FIG. 6

is a side diagram along the arrow VI of FIG.

4

.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 and 2

correspond to the prior art explained in the preamble and will thus not be described further.

FIG. 3

shows, by way of example a wristwatch wherein the top part of the middle part

1

is provided with a rotating bezel

2

bearing indications

20

represented by the figures

1

to

12

which are, as can be seen, all legible in the same direction, namely in the same direction as the time indications carried by a dial

3

for an analogue time display, closed by a crystal

5

.

FIG. 3

b

is shows this same wristwatch after bezel

2

has been rotated in the direction indicated by the arrow to bring the

figure 12

to the place previously occupied by the FIG.

5

. As can be seen, all the figures remain legible in the same direction, owing to the arrangement explained in more detail hereinafter with reference to

FIGS. 4

,

5

and

6

.

FIG. 4

shows, on a larger scale, the wristwatch of

FIG. 3

wherein it has been assumed that ring

4

of bezel

2

is transparent, and only one indication

20

corresponding to the

figure 12

has been shown in four positions at 12 o'clock, 9 o'clock, 6 o'clock and 5 o'clock. With reference also to

FIG. 6

, in which all the constituent elements are also assumed to be transparent, it can be seen that the indications are carried by the top part

9

a

of a stud

10

kept free in rotation about its axis

10

a

in a housing

30

arranged through the thickness of ring

4

, whose opening on the side of middle part

1

is closed by a circular base

6

having at least one extension

8

allowing it to be immobilised in rotation on middle part

1

. Lower part

9

b

of stud

10

, which has a larger diameter, forms with top part

9

a

a shoulder

9

c

allowing stud

10

to be held in housing

30

, after ring

4

has been snap fitted onto middle part

1

, for example by means of a raised portion

4

a

co-operating with a groove

1

a

of the middle part. In order to control the rotation of the bezel an annular spring

7

forming a catch is preferably inserted between ring

4

and base

6

outside the path described by the lower surface of studs

10

. Thus, when a rotational movement is imparted to the bezel, studs

10

are also driven and their rotational axis

10

a

describes a circle

18

of radius R. With reference also to

FIG. 5

, it can be seen that lower part

9

b

of studs

10

is provided with three studs

11

,

13

and

15

freely engaged in annular grooves

12

,

14

and

16

formed in base

6

, and having the same radius R as that of circle

18

described by the axis of studs

10

. Stems

11

,

13

and

15

are offset with respect to the axis of revolution

10

a

of studs

10

by the same distance d, and are offset with respect to each other, in the example shown, by an angle of 120°, although other angular offsets may by selected without departing from the scope of the present invention. Another feature of the invention is that all the stems have to have different dimensions. Indeed, by increasing the number of stems, and thus the number of guide grooves, a new difficulty is created, in that the centres

12

a

,

14

a

and

16

a

of grooves

12

,

14

and

16

are offset with respect to the centre of dial

3

in an identical configuration to that of the stems such that said grooves intersect each other again forming switches

19

(a single reference in

FIG. 4

for the sake of clarity).

It has thus seemed necessary to have grooves able to guide a single type of stem either as a function of its length, or as a function of its diameter, or preferably as a function of both of these parameters. By way of example for a stud whose lower part

9

b

has a diameter of 6 mm, all the stems are offset by a distance d=2 mm, stem

11

having a diameter of 0.5 mm and a length of 1 mm, stem

13

respectively 0.75 mm and 0.75 mm, and stem

15

respectively 1 mm and 0.5 mm. Given the stresses that are nonetheless exerted on stems

11

,

13

and

15

, studs

10

and stems

11

,

13

and

15

are preferably made entirely of metal, for example brass. Ring

4

and base

6

are, conversely, preferably made of a plastic material allowing the desired shape to be easily obtained and offering the advantage of reducing friction. If middle part

1

is also made of a plastic material, it is possible to omit base

6

and form grooves

12

,

14

and

16

directly in the top surface of said middle part

1

.

The invention is not limited to the embodiment that has just been described, or to a horological application. Indeed, there may be a different number of studs, for example only four studs to mark the four cardinal points in a compass-watch or six studs to mark the decompression stops in a diver's watch. Having three stems per stud corresponds to the preferred embodiment, but one could, as indicated at the beginning, have only two studs with a different angular offset to 180°, or conversely, four stems, which would not however bring any obvious advantage technically.

A rotating bezel of the type that has just been described can also be useful for any type of measuring dial, such as the dials of an aeroplane instrument panel, or those of a domestic appliance.

Claims

1. A rotating bezel allowing the same reading direction to be kept for the indications carried by a ring able to rotate freely on a base to which it is affixed to bring a selected indication opposite a determined marking of the base or of a dial, wherein the indications are marked on an outer surface of studs each kept free in rotation about their rotational axis in a housing provided through the thickness of the ring and opening onto the base, each stud including in its lower part at least two stems of different dimensions, offset by the same distance from the rotational axis of the studs, and having an angular offset of less than 180°, each stem being guided during rotation of the bezel by a circular groove formed in the base and having a cross-section adapted to the dimensions of each stem, a radius equal to that of the circle described by the rotational axis of the studs, the centres of each groove having, with respect to the centre of the dial, exactly the same arrangement as the stems with respect to the rotational axis of the studs.
2. A rotating bezel according to claim 1, wherein the stems have different lengths.
3. A rotating bezel according to claim 1, wherein the stems have different diameters.
4. A rotating bezel according to claim 1, wherein the stems have both different lengths and different diameters.
5. A rotating bezel according to claim 1, wherein each stud includes three stems.
6. A rotating bezel according to claim 5, wherein the three stems have an angular offset of 120°.
7. A rotating bezel according to claim 1, wherein the ring and the base are made of a plastic material, and the studs and the stems are made of metal.
8. A rotating bezel according to claim 1, wherein an annular spring forming a catch is further inserted between the ring and the base, outside the path described by the lower surface of the studs.
9. A timepiece wherein it includes a rotating bezel according to claim 1, atop a middle part of said timepiece.
10. A timepiece according to claim 9, wherein the base of the bezel is snap fitted onto the top surface of the middle part.
11. A timepiece according to claim 9, wherein the base of the bezel is integral with the middle part.
12. A timepiece according to claim 9, wherein the indications carried on the studs are time indications, corresponding to the figures from 1 to 12.

Priority Claims (1)

Number	Date	Country	Kind
0413/02	Mar 2002	CH

US Referenced Citations (5)

Number	Name	Date	Kind
4035617	Banner	Jul 1977	A
5490123	Biver	Feb 1996	A
5541895	Nussbaum	Jul 1996	A
6310835	Mantoan et al.	Oct 2001	B1
6565253	Yang	May 2003	B1

Foreign Referenced Citations (2)

Number	Date	Country
436468	Jul 1991	CH
573386	Dec 1993	CH

Non-Patent Literature Citations (1)

Entry
Patent Abstracts of Japan, vol. 1996, No. 8, Aug. 30, 1996 & JP 08 110382 (Yamamoto Seisakusho KK), Apr. 30, 1996.

Mysterious rotating bezel

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

US Classifications