FR3058535A1 - HINGE FOR EYEWEAR MOUNT - Google Patents

Abstract

The hinge for spectacles comprises a part 20 provided with a rack 23 and a part 80 provided with a toothed portion 43. They are assembled so as to mesh the toothed portion 43 with the rack 23. Their relative movement by meshing is accompanied by a pivoting between the closed and open positions of the eyeglass branch relative to the face of glasses. An elastic blade 44 constrains the gear portion 43 in engagement with the rack 23 and provides a return force to the open and closed positions. The piece 80 is made by removable assembly by elastic interlocking of two parts 40, 60 for assembling the two piece 80 by mutual interleaving. Achieved with just three base pieces, this hinge is also easy to assemble and disassemble.

Description

(54) HINGE FOR GLASSES FRAME.

Holder (s): KANG JUN MO.

Agent (s): CABINET REINHARDT YVES THARINDER.

FR 3 058 535 - A1 _ The hinge for glasses comprises a part 20 provided with a rack 23 and a part 80 provided with a gear wheel portion 43. They are assembled so as to mesh the gear wheel portion 43 with the rack 23. Their relative displacement by meshing is accompanied by a pivoting between the closed and open positions of the spectacle branch relative to the spectacle face. An elastic blade 44 constrains the gear wheel portion 43 in engagement with the rack 23 and provides a return force towards the open and closed positions. The part 80 is produced by dismountable assembly by elastic fitting of two parts 40, 60 making it possible to assemble the two parts 80 by mutual nesting. Feasible with only three basic parts, this hinge is also easy to assemble and disassemble.

i

HINGE FOR GLASSES FRAME

The present invention relates to the field of glasses provided with corrective and / or filtering glasses and intended to be placed on the nose, in front of the eyes of an individual. More specifically, it relates to a hinge for the frame of the glasses which forms the articulation between one of the arms of the frame and the face of the frame.

There are many types of hinges for more or less complex and reliable glasses frames which implement a pure pivot connection to ensure the opening and closing of the glasses branches relative to the face of glasses. An advantageous characteristic for the user is that the hinges maintain the arms in position relative to the face of the frame both in the open position - that is to say the position in which the glasses are used - and in closed position - that is, when the arms are folded against the face of the frame.

This characteristic is sometimes provided by a tight assembly of the hinge by means of a screw and providing mechanical resistance by friction when passing from the open position to the closed position and vice versa. A disadvantage of this solution is that the screw tends to loosen as the branches open / close, which weakens the holding in position, or even results in disassembly of the hinge and possibly the loss of screw. Furthermore, the mechanical resistance by friction is substantially constant when passing between the two extreme positions of the branches, which has the effect of keeping the branches in any angular position relative to the frame as soon as the user ceases to stress the branches. . It is preferable that the hinges favor the passage of the branches into the closed or open position when the user folds or unfolds the branches when he stops urging the branches before reaching one of these two positions.

There are other hinges for spectacle frames including a spring which are more favorable from this point of view. These also allow an elastic over-displacement of the branches beyond the open position in order to facilitate the passage of the branches on either side of the temples of the user when he puts the glasses on his nose. . However, this type of hinge is particularly complex, given the number of parts that compose it and its difficulty of assembly. Its disassembly - for example for repair purposes - is just as complex.

The object of the present invention is to provide a new and improved hinge technology for spectacle frames.

12FR-161108-Patent application.docx

Thus, according to one aspect, the present invention provides a hinge for glasses, comprising:

a first element intended to be fixed to a face of spectacles or to a spectacle lens, or else which comes integrally with a circle of spectacles, and

- A second element intended to be fixed to a branch of glasses, or else which comes integrally with a branch of glasses, the hinge allowing a relative pivoting of the two elements for the purpose of opening and closing of the branch of glasses with respect on the face of glasses, the hinge further comprising:

- a first part comprising a rack, and

- a second part comprising a portion of a toothed wheel, in which:

the first element is part of one of the two parts and the second element is part of the other of the two parts, the two parts are assembled with each other so as to mesh the portion of toothed wheel of the second part with the rack of the first part and allow relative movement of the two parts by mutual engagement between a first and a second relative position which is accompanied by a relative pivoting of the two elements between a first relative angular position and a second position relative angular corresponding respectively to a closed position and to an open position of the branch of glasses with respect to the face of glasses, and the two parts cooperate to provide a force for holding the position of the two parts together when the two elements are in the first and second relative angular positions.

The use of a toothed wheel / rack link to achieve the hinge provides a longitudinal displacement between the parts thereof in addition to the desired pivoting, which longitudinal displacement facilitates - compared to the case of a pure pivot connection the establishment of forces for holding in position, or even for restoring, between the two pivoting parts of the hinge, and this in a controlled manner if necessary as a function of their relative angular position.

According to preferred embodiments, the invention comprises one or more of the following characteristics:

the effort to maintain the position of the two parts together is an elastic retention effort;

the two rooms are configured so that:

o the second part is resiliently biased in displacement by meshing towards the first relative position of the two parts from a third relative position of the two parts which is intermediate between the first and second relative position; and / or o the second part is elastically stressed in displacement by meshing towards the second relative position of the two parts from a fourth relative position of the two parts which is intermediate between the first and second relative positions, the third and fourth relative positions may be different or the same;

the second part comprises an elastic blade arranged on the side opposite to the gear wheel portion which elastic blade is in abutment against a wall of the first part so as to elastically urge the gear wheel portion of the second part to mesh with the rack of the first part, the blade of the second part and the wall of the first part being configured so that:

o the second part is resiliently biased in displacement by meshing towards the first relative position of the two parts from the third relative position; and / or o the second part is resiliently biased in displacement by meshing towards the second relative position of the two parts from the fourth relative position;

the wall of the first part comprises a profile having at least one projection with which the elastic blade of the second part cooperates so that the second part is thus stressed;

the first piece includes:

o a first stop against which the second part comes to bear when the two elements reach the first relative angular position; and / or o a second stop against which the second part comes to bear when the two elements reach the second relative angular position;

the two parts are configured to allow relative pivoting of the two elements against an elastic restoring force beyond the second relative angular position relative to the first relative angular position, said possibility of relative pivoting of the two elements against an elastic restoring force beyond the second relative angular position being preferably provided by the elastic blade of the second part; the two parts are kept assembled by mutual nesting, one of the two parts, preferably the second, being obtained by fixed assembly of two parts, the other part preferably being made in one piece from material;

the two parts are kept assembled by form locking, their assembly being obtained by elastic deformation of at least one of the two parts preferably by relative pivoting of a quarter turn after engagement of one with the other;

the assembly of the two parts is also removable by elastic deformation so as to be able to disassemble the two parts from one another, the disassembly of the two parts being preferably done by relative pivoting by a quarter of a turn;

one of the parts has two parallel arms between which the other part is held;

the first part has at least one arm in which is formed a through opening, the rack being defined by a portion of the wall of the opening;

it is the first part which has two parallel arms which each have a through opening, a respective rack being defined by a portion of the wall of each opening, and it is the second part which is constituted by fixed assembly of two parts, to know :

o a first part having two portions of parallel toothed wheels linked together by an intermediate section, each of the portions of toothed wheels being in engagement with a respective rack of the first part, and o a second part forming an arm assembled on the intermediate section from the first part;

the hinge is in the form of an assembly ready to assemble;

The invention also relates to a spectacle frame, comprising a frame face and at least one branch pivotally articulated to the face by means of a hinge according to the aforementioned aspect of the invention.

Other aspects, characteristics and advantages of the invention will appear on reading the following description of a preferred embodiment of the invention, given by way of example and with reference to the attached drawing.

FIG. 1 represents a perspective view of glasses comprising hinges according to a preferred embodiment of the invention.

Figure 2 is an exploded view of the glasses of Figure 1 in which one of the branches and the corresponding hinge have been omitted for convenience of representation.

Figures 3 to 5 each show two views (a) and (b) of another of the three constituent parts of the hinge, namely each time a front view and a top view.

Figures 6 and 7 each show the same section of the part of Figure 5 along the section plane A-A opposite each time from a top view of the part of Figure 4, but in a relative perpendicular positioning.

FIG. 8 represents four perspective views (a) to (d) corresponding to successive stages in the assembly of the hinge.

FIG. 9 represents three top views (b) to (d) corresponding to views (b) to (d) of FIG. 8.

Figure 10 shows four perspective views (a) to (d) of the hinge, each in a different pivoting position.

Figure 11 shows a top view of the glasses of Figure 1 illustrating the possibility of additional pivoting of the branch relative to the face beyond the open position of use provided by the hinge.

FIG. 12 represents four perspective views (a) to (d) and FIG. 14 three top views (a) to (c) each corresponding to stages of disassembly of the hinge.

As can be seen in Figure 1, the glasses 1 has a frame 3 supporting two corrective and / or filter lenses 2a, 2b. The frame 3 comprises a face 4 and two branches 5 a, 5b. The glasses 2a, 2b are received in the face 4. Each branch 5a, 5b is pivotally hinged to the face 4 by means of a respective hinge 6a, 6b. The branch 5a is shown in the closed or folded position while the branch 5b is shown in the open or unfolded position, that is to say the usual position of use when the individual wears the glasses on his nose. The face 4 comprises a bridge 10 connecting two circles 11a, 11b each holding one of the glasses 2a, 2b. In this case, the circles 11a, 11b are partial in the sense that they do not surround the lower part of the glasses 2a, 2b. The face 4 also includes two support plates on the wearer's nose, only one of which 12b is visible in FIG. 1.

In the open position, the branches 5a, 5b are conventionally provided for coming to bear on the ears or against the wearer's temples in order to maintain the face 4 on his nose and the glasses 2a, 2b in front of his eyes.

It will be understood that the hinges according to the invention can be used for any type of spectacle frame other than that which has just been described, regardless of whether it is metallic or plastic, whether it includes complete circles, partial or no circles at all, whether the hinges are each fixed to a circle or directly to the glass 2a or 2b, etc.

As can be seen in FIG. 2, the hinge 6a is constituted, in the disassembled state, by three parts 20, 40 and 60. The part 20 is designed to be fixed by one end 21 to the glass 2a. Alternatively, the part 20 is provided to be fixed by its end 21 to the circle 11a. The attachment of the part 20 to the glass 2a or to the circle 11a is carried out by any suitable means known per se, such as by screwing, which is why it has not been illustrated in the figures. Alternatively again, the part 20 comes in one piece with the circle 11a, for example by molding a plastic material.

The part 60 is designed to be fixed by one end 61 to the branch 5a. The attachment of the part 60 to the branch 5a can be achieved by any suitable means known per se such as by interlocking or gluing, which is why it has not been illustrated in the figures. Alternatively, the part 60 comes in one piece with the branch 5a, for example by molding a plastic material.

As can be seen in FIG. 3, the part 20 comprises two parallel arms 31a, 31b in the extension of a common portion 30. The free end of the common portion 30 constitutes the end 21 of the part 20.

A through opening 22 is formed in the two arms 31a, 31b. In at least one of the arms 3 la, 3 lb, preferably both, a length portion of the wall defining the opening 22 forms a rack 23. The rack 23 is connected on either side to a respective arcuate portion 24, 25 of the wall defining the opening 22. The two arcuate portions 24, 25 meet by means of a projection 26 in an area opposite the rack 23.

As can be seen in FIG. 4, the part 60 has the general shape of a key. It comprises an arm 63, the free end of which constitutes the end 61. On the side opposite the end 61, the arm 63 is continued by a head 62 having a through and profiled opening 64. The opening 64 opens radially by a mouth 65 on the outer periphery of the head 62. The head 62 with its opening 64 is used to assemble the part 60 with the part 40 which we will describe in more detail later.

As can be seen in FIG. 5, the part 40 has two opposite parts 41a, 41b linked together by an intermediate section 42. The two opposite parts 41a, 41b are each provided to be placed in a respective opening 22 of the part 20 and cooperate with this opening. In this case, the parts 41a, 41b each comprise a portion of toothed wheel 43 and an elastic blade 44. The elastic blade 44 is connected by one end to the rest of the corresponding part 41a, 41b while its opposite end is free. It has an arched shape. The part 40 is intended to be inserted into the opening 22 of the arms 3a, 3 lb of the part 30. More particularly, each of the two opposite parts 41a, 41b is intended to be placed in the opening 22 of another arms 31a, 31b of the part 30 so that the elastic blade 44 urges the portion of toothed wheel 43 meshing with the teeth of the rack 23. Of course, only one of the parts 41a, 41b can be provided with a portion of toothed wheel 43 in the case where only one of the arms 31a, 31b has a rack 23 in the opening 22.

The intermediate section 42 is configured to be assembled with the head 62 of the part 60 by an embedding connection so as to form a single part 80 after assembly. The assembly is preferably carried out by elastic interlocking. It is advantageous that it is a dismountable assembly. Thus, the parts 40 and 60 are kept assembled together by shape locking, the assembly being obtained by elastic deformation of at least one of the two parts 40, 60 and the two parts 40, 60 also being able to be disassembled by elastic deformation.

This ability can be provided in particular in the following manner. The intermediate section 42 of the part 40 and the opening 64 of the part 60 have a corresponding asymmetrical cross section. The mouth 65 of the part 60 - which is narrower than the opening 64 - makes it possible to introduce the intermediate section 42 of the part 40 into the opening 64 through one side of the intermediate section 42 which has a width suitable for this end. Then, the form lock is obtained by a relative pivoting of the parts 40 and 60 bringing the sections of the intermediate section 42 and the opening 64 in correspondence. This pivoting operation is made possible by the elasticity of at least one of the two parts 40, 60, and more preferably by the elasticity of one of the jaws defining the opening 64. The thickness of the head 62 corresponds substantially to the height of the intermediate section 42 which separates the two parts 41a, 41b. The disassembly of the parts 40, 60 can be obtained by a similar relative pivoting operation.

In the example illustrated and best visible in Figures 6 and 7, the intermediate section 42 and the opening 64 have a corresponding generally rectangular cross section having a large side of length 'L' and a small side of length '1' to allow assembly and disassembly by relative pivoting of a quarter turn. The mouth 65 has a width corresponding substantially to the length '1' of the short side of the rectangular section and opens onto the long side of length 'L' of the rectangular section of the opening 64. On the side opposite the mouth 65, the opening 64 has a weakening slot 66 to give sufficient elasticity to the jaw 67 adjacent to the opening 64 for the assembly operation by relative pivoting between the parts 40, 60. To facilitate the 'assembly operation, the rectangular section of the intermediate section 42 has rounded or chamfered corners 42a.

Referring to Figures 8 and 9, a method of assembling the hinge 6a is as follows.

In a first step illustrated by view (a) of FIG. 8, the part 40 is inserted into the opening 22 of the arms 3a, 3 lb of the part 20 so that the gear wheel portions 43 are in taken with the corresponding racks 23 and that the part 40 is in abutment against the arcuate wall 25. As can be seen, the arcuate elastic blades 44 rest against the arcuate wall 25, which has the effect of elastically urging the toothed wheel portions 43 in engagement with the racks 23.

In a second step illustrated by the views (b) of FIGS. 8 and 9, the head 62 of the part 60 is inserted between the arms 3 la, 3 lb of the part 20 while presenting the mouth 65 opposite the short side of length '1' of the intermediate section 42 of the part 40 so that the intermediate section 42 comes to penetrate the opening 64 of the part 60. This then leads to the situation illustrated by the views (c) of FIGS. 8 and 9 .

In a third step, the part 60 is rotated 90 ° relative to the part 40 as indicated by the arrows in the views (c) of Figures 8 and 9, which has the effect of locking the parts 40 and 60 by cooperation of form of the intermediate section 42 and the opening 64 as explained above. This leads to the situation illustrated by views (d) of FIGS. 8 and 9. Consequently, the parts 40 and 60 are assembled together by an embedding connection so as to behave as a single part 80 during the operation of the hinge. 6a. In addition, the hinge 6a is now in the assembled state since the part 20 on the one hand, and the part 80 resulting from the rigid assembly of the parts 40 and 60 on the other hand, are interlocked due to their mutual nesting , the part 40 being held in the part 20 due to the part 60 to which it is rigidly assembled and which passes between the arms 31a, 31b.

This assembly operation by relative pivoting of the parts 40 and 60 is facilitated by the fact that the part 40 is in abutment against the wall 25 of the part 20, which prevents the movement of the part 40 in the opening 22 during the pivoting assembly operation. In other words, the pivoting force for assembly purposes can be applied between parts 20 and 60.

This assembly process can be carried out manually without tools.

FIG. 10 illustrates the hinge 6a in the assembled state for different pivoting positions. View (a) shows the hinge 6a in an open position which corresponds to the case where the spectacle branch is open or unfolded with respect to the spectacle face without exerting external stress on the branch. The part 40 is then in abutment against the wall portion 25 of the part 20.

When the user actuates the part 80 by urging on the spectacle branch in order to fold it back and bring it into the closed or folded position against the face 3 of the spectacles 1 or close to it, the part 40 moves by meshing with toothed wheel portions 43 in the racks 23 towards the wall portion 24 of the opening 22. This displacement of the part 40 therefore causes it to pivot, and consequently, that of the part 60 relative to the part 20, and therefore of the corresponding branch 5a, 5b with respect to the face 3 of the glasses 1. In the closed or folded position, the part 40 is in abutment against the wall portion 24 of the part 20. Alternatively, it is the branch 5a , Corresponding 5b which abuts against the face 3 of the glasses 1 or against the other of the branches 5a, 5b before the part 40 abuts against the wall portion 24. Conventionally, the pivot angle between the open position and closed position ée between parts 20 and 60 is substantially 90 °.

During the displacement by engagement of the part 40 in the openings 22, the elastic blades 44 are elastically deformed as the projection 26 of the openings 22 passes. This is made possible because the elastic blades 44 are spaced from the rest of the parts 41a, 41b of room 40: cf. the spacing distance 'd' at the free end of the blades 44. This elastic deformation of the blades 44 during the passage over the projection 26 of the openings 22 create a force elastically biasing the part 40 towards the open position or towards the closed position of the hinge 6a depending on whether the part 40 is moved from the open position or from the closed position.

Furthermore, when the hinge 6a is in the open position, the fact that the elastic blades 44 are spaced from the rest of the parts 41a, 41b of the part 40 provides a possibility of additional pivoting of the part 60 relative to the part 20 beyond from the open position by elastic deformation of the elastic blades 44 against the wall portions 25. This situation is illustrated by view (d) of FIG. 10 and by FIG. 11 in which this possibility of additional pivoting is identified by the angle 'AT'.

FIG. 11 illustrates the usual open position of the branch 5a - that is to say in the absence of external stress on the branch 5a - and its position referenced 5a 'when it is stressed towards the outside by the user so as to generate this additional pivoting. As soon as the external stress ceases, the branch returns to its usual open position - referenced 5a in FIG. 11 - due to the elastic return force of the blades 44. The maximum additional pivot angle 'A' is preferably between 10 ° and 30 °, more preferably between 10 ° and 20 °, or even between 10 ° and 15 °.

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This possibility of additional pivoting is advantageous because it allows the user to enlarge the angular opening of the branches 5a, 5b to more easily pass the branches on either side of his head.

Referring to Figure 12, we will describe a method of disassembly of the hinge 6a.

View (a) of Figures 12 illustrates the hinge 6a in the assembled state in the open position. While view (a) of Figure 12 shows the hinge from above, its view (b) shows from below. It shows that the part 40 has an imprint 45 in the part 41b. The cavity 45 is intended to be engaged by a key or a screwdriver. In our example, this is a hexagon socket intended to be engaged by a corresponding ‘C’ key.

In a first step of the disassembly process, the key ‘C 'is engaged in the cavity 45.

Still with reference to view (b) of FIG. 12, in a second step, the part 60 is actuated while maintaining the part 40 in position using the key 'C' so as to rotate the part 60 90 ° relative to the part 40. This pivoting is made possible due to the elasticity imparted to the jaw 67 of the part 60 by the weakening 66 of the opening 64, as well as by the rounded or chamfered corners 42a . The intermediate section 42 is then engaged by a short side of length ‘1’ in the mouth 65 of the head 62 of the part 60.

From this position, a third step consists in pulling on the part 60 in the direction opposite to the part 40 so as to remove the head 62 from the intermediate section 42, as illustrated by view (c) of FIG. 12.

In a fourth step, the part 40 is removed from the opening 22 of the arms 31a, 3 lb, as illustrated by view (d) of FIG. 12.

It will be noted that, in our example, the direction of pivoting during the assembly and disassembly operations of the parts 40 and 60 are the same because only two opposite corners 42a of the rectangular section of the intermediate section 42 are rounded or chamfered. The fact that the other two corners of the rectangular section are not chamfered provide an irreversible lock between the parts 40 and 60 in the other direction of pivoting.

The parts 20, 40 and 60 can be made of any suitable material, in particular metal or by plastic molding.

It will be understood that the hinge 6b is similar to the hinge 6a, except for having an inverted structure to allow pivoting of the branch 5b in the other direction compared to the branch 5a.

As is apparent from the above description, the hinge can advantageously be implemented with only three basic parts and be assembled and disassembled in a very simple manner unlike the spring hinges of the prior art, while providing characteristics similar to the latter, in particular a restoring force towards the open and closed position and holding in these positions, as well as an elastic over-displacement by pivoting beyond the open position. Similarly, it can be implemented by providing a holding force in the open and closed position without it significantly decreasing with its repeated use, unlike the case of screw hinges of the prior art.

Of course, the present invention is not limited to the examples and to the embodiment described and shown, but it is susceptible of numerous variants accessible to those skilled in the art.

For example, the design of parts 20, 40 and 60 may be different to change the way of assembling them by mutual nesting. Thus, the part 20 can be provided with a single arm similar to the arm 31a or 31b in which is formed an opening 22 as described. Correspondingly, the part 40 is modified to present only a single part of the type 41a, 41b having a portion of toothed wheel 43 and an elastic blade 44 as described. The intermediate section 42 is replaced by two similar profiled sections each placed on another side of the gear wheel portion 43 while the part 60 has a common part extending by two parallel heads 62 spaced apart intended to come each s 'fitting elastically onto another of the two profiled sections of the part 40. The part 20 is in this case arranged between the two heads 62 of the part 60.

According to another example which is a simplified version of the hinge, it is intended to provide only a force for holding the hinge in the open position and in the closed position, without providing a restoring force towards these two positions, nor of possibility of over-displacement by pivoting against a restoring force beyond the open position. In this simplified version, the parts 41a, 41b of the part 40 are devoid of elastic blades 44 and the wall portion of the opening 22 in front of the rack 23 of each arm 31a, 31b is straight without projection 23, the portion non-toothed parts 41a, 41b being round to cooperate by contact with this wall portion of the opening 22 so as to maintain the portion of toothed wheel 43 in mesh with the corresponding rack 23. The force for holding the hinge in the open position and in the closed position is provided by elastic clamping of the arm 61 between the arms 31a, 31b when the arm 61 reaches the corresponding positions between the arms 31a, 31b, the elastic clamping being provided by a localized narrowing of the spacing of the arms 31a, 31b.

Claims (14)

1. Hinge (6a; 6b) for glasses (1), comprising: a first element (21) intended to be fixed to a face of spectacles (4) or to a spectacle lens (2a; 2b), or else which comes integrally with a circle of spectacles (11a; 11b), and - a second element (61) intended to be fixed to a branch of glasses (5a; 5b), or else which comes integrally with a branch of glasses, the hinge allowing relative pivoting of the two elements (21, 61) for the purposes opening and closing the spectacle branch (5a; 5b) relative to the spectacle face (4), the hinge further comprising: a first part (20) comprising a rack (23), and - a second part (80) comprising a portion of toothed wheel (43), in which: the first element (21) is part of one (20) of the two parts and the second element (61) is part of the other (80) of the two parts, the two parts (20, 80) are assembled one with the other so as to mesh the toothed wheel portion (43) of the second part (80) with the rack (23) of the first part (20) and allow relative movement of the two parts (20, 80 ) by mutual engagement between a first and a second relative position which is accompanied by a relative pivoting of the two elements (21,61) between a first relative angular position and a second relative angular position corresponding respectively to a closed position and to a open position of the spectacle arm (5a; 5b) relative to the spectacle face (4), and the two parts (20, 80) cooperate to provide a force for holding the position of the two parts together when the two elements (21, 61) are in the first e and second relative angular positions, the effort of holding the position of the two parts together preferably being an elastic retention effort. 2. Hinge according to claim 1, in which the two parts (20, 80) are configured so that: the second part (80) is elastically biased in displacement by meshing towards the first relative position of the two parts (20, 80) from a third relative position of the two parts (20, 80) which is intermediate between the first and second relative position; and / or the second part (80) is elastically biased in displacement by meshing towards the second relative position of the two parts (20, 80) from a fourth relative position of the two parts which is intermediate between the first and second relative position , the third and fourth relative positions may be different or the same. 3. Hinge according to claim 2, in which the second part (80) comprises an elastic blade (44) arranged on the side opposite to the toothed wheel portion (43) which elastic blade is in abutment against a wall (24, 25, 26) of the first part (20) so as to elastically urge the portion of toothed wheel (43) of the second part (40) meshing with the rack (23) of the first part (20), the blade (44) of the second part (44) and the wall (24, 25, 26) of the first part (20) being configured so that: the second part (80) is resiliently biased in displacement by meshing towards the first relative position of the two parts from the third relative position; and / or the second part (80) is resiliently biased in displacement by meshing towards the second relative position of the two parts from the fourth relative position. 4. Hinge according to claim 3, wherein the wall (24, 25, 26) of the first part (20) comprises a profile having at least one projection (26) with which the elastic blade (44) of the second part ( 80) cooperates so that the second part (80) is thus biased. 5. Hinge according to any one of claims 1 to 4, in which the first part (20) comprises: - A first stop (24) against which the second part (80) comes to bear when the two elements (21, 61) reach the first relative angular position; and or - A second stop (25) against which the second part (80) comes to bear when the two elements (21, 61) reach the second relative angular position. 6. Hinge according to any one of claims 1 to 5, in which the two parts (20, 80) are configured to allow relative pivoting (A) of the two elements (21, 61) against a force. elastic return beyond the second relative angular position relative to the first relative angular position, said possibility of relative pivoting of the two elements (21, 61) against an elastic return force beyond the second relative angular position preferably being provided by the elastic blade (44) of the second part (40, 60). 7. Hinge according to any one of claims 1 to 6, in which the two parts (20, 80) are kept assembled by mutual nesting, one of the two parts, preferably the second (80), being obtained by assembly fixed from two parts (40, 60), the other part (20) preferably being made in one piece from one material. 8. Hinge according to claim 7, in which the two parts (40, 60) are kept assembled by shape locking, their assembly being obtained by elastic deformation of at least one (60) of the two parts, preferably by relative pivoting. a quarter turn after engagement of one with the other. 9. Hinge according to claim 8, wherein the assembly of the two parts (40, 60) is further removable by elastic deformation so as to be able to disassemble the two parts (20, 80) from one another, the disassembly of the two parts (40, 60) preferably by relative pivoting of a quarter turn. 10. Hinge according to any one of claims 7 to 9, in which one (20) of the parts has two parallel arms (31a, 31b) between which the other part (80) is held. 11. Hinge according to claim 10, wherein the first part (20) has at least one arm (31; 3 lb) in which is formed a through opening (22), the rack (23) being defined by a portion of the wall of the opening (22). 12. Hinge according to claim 10 or 11, in which: it is the first part (20) which has two parallel arms (3la, 3 lb) which each have a through opening (22), a respective rack (23) being defined by a portion of the wall of each opening (22) , and it is the second part (80) which is constituted by fixed assembly of two parts (40, 60), namely: a first part (40) having two portions of parallel toothed wheels (43) linked together by an intermediate section (42), each of the portions of toothed wheels (43) being in engagement with a respective rack (23) of the first piece (20), and 5 o a second part (60) forming an arm assembled on the intermediate section (42) of the first part (40). 13. Hinge according to any one of claims 1 to 12 in the form of a ready-to-assemble assembly. 14. Spectacle frame (3), comprising a frame face (4) and at least one branch (5a; 5b) pivotally articulated to the face by means of a hinge (6a; 6b) according to any one of claims 1 to 12. 1/9 σ> ul 2/9 "Jtt ry 3/9