FR3113957A1 - Articulation for linking a branch and a frame supporting a pair of optical lenses. - Google Patents

Abstract

Articulation 1a to form an articulated connection between a branch 2a and a frame 3, comprising:- a first part (11a) having an internal recess (11a1) and a lateral opening (11a2);- a second part (12a) extending from an area external to the first piece (11a) to the internal recess (11a1) passing through said side opening (11a2); and - a pivot (13a) passing through a first passage (11a3) formed in the first part (11a) to produce a pivot connection between these first and second parts (11a, 12a). A friction part (14a) is positioned inside at least one of said first passage (11a3) and said internal recess (11a1) of the first part (11a) to oppose the pivoting of said second part (12a) vis-à-vis the first part (11a) around a main axis (AA) of the pivot (13a). FIGURE OF THE ABRIDGE: Fig. 3

Description

Articulation for linking a branch and a frame supporting a pair of optical lenses.

The present invention relates to the field of optical devices and in particular that of joints for connecting a branch to a frame carrying optical lenses.

BACKGROUND OF THE INVENTION

It is known, for example from document EP0945751A1, a joint forming an articulated connection between a branch and a frame supporting a pair of optical lenses. This articulation allows free and unconstrained pivoting of the temple in relation to the frame, which can cause the user a feeling of discomfort linked to the instability of the orientation of the temples in relation to the frame.

In some cases, this joint can be accidentally disassembled at the risk of causing the frame to fall and the optical lenses to break.

OBJECT OF THE INVENTION

An object of the present invention is to provide a joint to form an articulated connection between a branch and a frame to support a pair of optical lenses, this joint at least partially solving all or part of the aforementioned drawbacks of the prior art.

To this end, the invention relates to a joint for forming an articulated connection between a branch and a frame for supporting a pair of optical lenses, the joint comprising:
- A first part having an internal recess and a lateral opening extending from said internal recess to a zone external to the first part;
- A second part extending from the zone external to the first part as far as said internal recess of the first part passing through said lateral opening; And
- a pivot extending along a main axis of the pivot, this pivot passing through a first passage formed in the first part and through a second passage formed in the second part to provide a pivot connection between these first and second parts around said main axis of the fulcrum.

The joint according to the invention is essentially characterized in that it comprises a friction part positioned inside at least one of said first passage and said internal recess of the first part, the friction part forming a interface between a contact surface belonging to said first part and a contact surface belonging to said second part to oppose, by friction of this friction part against at least one of said contact surfaces, the pivoting of said second part vis-à-vis the first part around said main axis of the pivot.

The contact surfaces of said first and second parts against the friction part are located inside the first part (that is to say in the first passage and/or in the internal recess of the first part) which preserves the friction part and the contact surfaces, vis-à-vis the external environment to the joint.

In this sense, the joint according to the invention generates, thanks to a specific friction part, a torque opposing the pivoting of the second part with respect to the first part around said main axis of the pivot (this axis main axis of the pivot is a longitudinal axis of symmetry of the pivot). As this friction part is located in the first part of the joint, it is preserved there, which helps to maintain a constant friction function throughout the life of the joint.

According to a particular aspect of the joint according to the invention, said contact surface belonging to said second part may have a roughness expressed as the arithmetic mean deviation Ra greater than 500 μm.

According to another particular aspect of the joint according to the invention, said contact surface belonging to said second part can be ribbed to increase the friction against the friction part.

According to a second aspect, the invention relates to an optical device comprising a mount for supporting a pair of optical lenses and comprising first and second arms.

This optical device is essentially characterized in that:
- the first branch is articulated vis-à-vis the frame via a first articulation according to any one of the embodiments of the articulation according to the invention; and in that
- the second branch is articulated with respect to the frame via a second articulation according to any one of the embodiments of the articulation according to the invention, the first part of the first articulation being fixedly assembled to the frame, the second part of the first articulation and the first branch being fixedly fastened together, the first part of the second articulation being fixedly assembled to the frame, the second part of the second articulation and the second branch being fixedly fastened together.

Thus, each branch of the optical device according to the invention is pivotally mounted with respect to the frame by means of a joint according to the invention, which gives the optical device the aforementioned advantages inherent in the joints according to the invention.

Other characteristics and advantages of the invention will emerge clearly from the description given of it below, by way of indication and in no way limiting, with reference to the appended drawings, in which:

there is an optical device according to the invention comprising a frame 3 carrying optical lenses 4a, 4b, first and second auricular support branches 2a, 2b and first and second articulations 1a, 1b according to the invention, the first of these branches 2a is connected in an articulated manner to one of the sides of the frame 3 via the first of these joints 1a, the second of these branches 2b is connected in an articulated manner to another of the sides of the frame 3 via the second of these joints 1b;

there is an illustration showing two views of the second joint 1b according to the invention connected to the second auricular support branch 2b (left branch), this joint 1b is adapted for its attachment to the left side of frame 3, the first of these views is a perspective view showing an upper face of joint 1b (where one end of the pivot is seen) and the second of these views is a top view of joint 1b;

there is an illustration showing two alternate views of joint 1b of the , the first of these views is a perspective view from below showing an underside of the joint 1b and the second of these views is a top view of this joint 1b;

there is an exploded view in perspective of a joint according to the invention, in this case the first joint 1a, which is here arranged to fix the first auricular branch 2a (right branch) to the right side of the optical device frame according to the invention;

there is a perspective view of the second part of a joint according to the invention (in this case it is the second part 12a of the first joint 1a), this view illustrating a ribbed contact surface of the second part 12a to come into contact against the friction part and thus prevent rotation of the friction part vis-à-vis this contact surface of the second part;

there is an exploded view of a joint according to the invention observed in a partial section plane XX in which extend the main axis AA of the pivot and the longitudinal axis BB of the second part, that is to say the main axis of the auricular bearing branch;

there is a view of the joint of the while it is assembled, this view still being in the section plane XX, but this section is here an integral section to illustrate the truncated-conical outer surface of the pivot 13a which crushes the friction part 14a to force its radial expansion against the cylindrical contact surface S1 of the first part 11a and thus to adjust a friction torque opposing the pivoting of the second part 12a with respect to the first part 11a.

DETAILED DESCRIPTION OF THE INVENTION

There , presents an optical device 0 in accordance with the invention which comprises a mount 3 supporting a pair of optical lenses 4a, 4b and further comprising first and second ear support branches 2a, 2b.

The first branch 2a is articulated vis-à-vis the frame 3 via a first articulation 1a according to the invention and the second branch 2b is articulated vis-à-vis the frame 3 via a second articulation 1b according to the invention.

The different embodiments of a joint according to the invention will be presented later with reference to Figures 2a to 5b.

This mount 3 has a first location for receiving and supporting the first optical lens 4a of the pair of optical lenses and a second location for receiving and supporting the second optical lens 4b of the pair of optical lenses.

An optical lens is a component (usually called optical glass) that allows light to pass through to modify certain optical characteristics.

Such a lens is, for example, corrective of visual defects and/or simply protective, for example like a sun protection lens.

The frame 3 also has a nasal support area 3a arranged between the lenses 4a, 4b.

Each branch 2a, 2b comprises an auricular support zone which is specific to it.

Each auricular support zone is arranged so that the optical device 0 can be worn by a user with the nasal support zone 3a resting on the nose of the user and with the auricular support zones respectively resting on the user's right and left ears.

Each auricular support zone of a given branch may comprise a terminal auricular support curvature formed at one end of this given branch, this curvature being at a distance from the articulation connecting the branch to the frame.

The first joint 1a is symmetrical with the second joint 1b according to a symmetry orthogonal to a median plane M-M of the optical device 0.

In this case, this plane M-M passes through a central point of mount 3.

The first joint 1a, a first half of the nasal support zone 3a, the first branch 2a and the first lens extend on a first side of this plane M-M while the second joint 1b, a second half of the zone nasal support 3a, the second branch 2b and the second lens 4b extend from a second side of this plane M-M (these first and second sides of the plane M-M are on either side of the plane M-M).

Given this symmetry between the first and second joints 1a, 1b, the description which follows and which relates to the first joint 1a according to the invention is applicable mutatis mutandis to the second joint 1b according to the invention.

The first articulation 1a is arranged to form an articulated connection between the first branch 2a and the frame 3.

To this end, this articulation 1a comprises:
- A first part 11a having an internal recess 11a1 and a lateral opening 11a2 extending from said internal recess 11a1 to a zone external to the first part 11a (this first part forms a yoke); And
- a second part 12a extending from the zone external to the first part 11a as far as said internal recess 11a1 of the first part 11a passing through the said lateral opening 11a2 (this second part 12a is mounted in the yoke formed by the part 11a ).

This joint 1a also includes a pivot 13a which extends along a main axis of the pivot A-A.

This pivot 13a passes through a first passage 11a3 formed in the first part 11a (this first passage 11a3 opens into the internal recess 11a1) and through a second passage 12a3 formed in the second part 2a to produce a pivot connection between these first and second parts 11a, 12a around said main axis A-A of pivot 13a.

For the understanding of the invention, this pivot connection leaves between the first part and the second part only a freedom of rotation around the geometric axis that constitutes the main axis A-A of the pivot 13a.

The side opening 11a2 of the first part 11a is delimited by first and second flat surfaces Sp1, Sp2 of this first part 11a which are parallel to each other.

The second part 12a also has an upper flat surface Ssup and a lower flat surface Sinf which are formed on either side of the second part 12a and which are parallel to each other.

The upper flat surface Ssup can rest against the first flat surface Sp1 or at a slight distance from this surface Sp while the lower flat surface Sinf faces the second flat surface Sp2 of the first part.

Thus, the first part 11a forms a yoke in which said second part 12a is received.

Preferably, the thickness of the second part measured between the lower Sinf and upper surfaces Ssup is equal, to plus or minus 0.05% of this thickness, to the distance between the first and second flat surfaces Sp1, Sp2 of the first part.

Preferably, the lower Sinf and upper Ssup flat surfaces are arranged so that the second part 12a is clamped between said surfaces Sp1 and Sp2 of the first part throughout the pivoting of the second part vis-à-vis the first part around the main axis A-A of the pivot.

Preferably, the second part 2a and the lateral opening 11a2 are shaped so as to define a maximum angle of pivoting of the second part 12a with respect to the first part 11a, this maximum angle being less than 120° of angle, this angle maximum being generally 90°.

When this maximum angle of pivoting is reached, the second part abuts against an edge of the side opening 11a2 which prohibits the pivoting of this second part 2a beyond this maximum angle.

As illustrated in Figures 3, 5b, the joint 1a also includes a friction piece 14a, in this case a friction ring / washer, which is positioned inside at least one of said first passage 11a3 and said internal recess 11a1 of the first part 11a.

In the example shown in , the friction piece 14a is essentially arranged in the first passage 11a3.

This friction part 14a is a part of revolution whose axis of revolution coincides with said main axis A-A of the pivot 13a.

This friction part is preferably an elastically deformable washer in radial directions of the axis of revolution of the friction part.

In other words, this friction piece 14a is elastically deformable along radial directions perpendicular to the main axis A-A of the pivot 13a so that, in response to a compression of the friction piece 14a between the pivot 13a and the second part 12a, the friction part 14a expands radially and comes into compression against a contact surface S1 belonging to the first part 11a, this contact surface S1 being a surface of revolution whose main axis of revolution coincides with said main axis A-A of the pivot 13a.

To promote this radial expansion of the friction part 14a, the pivot 13a may include, as illustrated in Figures 5a, 5b, an outer surface S3 of frusto-conical shape at least partially positioned in a central passage 14a1 of the friction part 14a.

This outer surface S3 of truncated-conical shape extends between a base B1 of the truncated-conical and a narrow end B2 of the truncated-conical, the narrow end B2 of the truncated-conical is located closer to the second part 12a than the base B1 of the truncated cone.

The frusto-conical surface S3 of the pivot is a portion of the external surface of a cone delimited between a first plane in which extends the base B1 of this cone and a second plane parallel to this first plane which extends between the apex of the cone and the base of the cone.

The intersection between the cone and this second plane forms the narrow end B2 of the truncated conic.

Thus, the outer surface S3 of frusto-conical shape bears against the friction part 14a so as to force the radial expansion of this friction part.

The friction part is arranged between a shoulder EP of said pivot 13a and a contact surface S2 belonging to said second part 12a. As understood from Figures 4 and 5a, 5b, the limit of the shoulder EP is in the same plane as the base B1 of the truncated cone.

The contact surface S2 is preferably a flat surface.

The term shoulder EP denotes an abrupt change in the diameter of the pivot 13a.

This shoulder constitutes a support surface for the pivot against the friction part, this support surface being a flat surface internally delimited by the wide base B1 of the frusto-conical and externally delimited by a circular rim having as its center the main axis A-A of pivot.

This friction part 14a forms an interface between a contact surface S1 belonging to said first part 11a and a contact surface S2 belonging to said second part 12a to oppose, by friction of this friction part 14a against one at the least of said contact surfaces S1, S2, when said second part 12a pivots with respect to first part 11a around said main axis A-A of pivot 13a.

As the contact surfaces S1, S2 of the first and second parts and the friction part 14a are inside the first part, these elements are preserved which increases the durability of the joint.

As illustrated on the , the contact surface S2 which belongs to the second part 12a is preferably ribbed to increase the friction against the friction part 14a and thus prevent the pivoting of this friction part with respect to the second part 12a around the main axis AA of the pivot.

Conversely, the contact surface S1 belonging to the first part 11a is smooth.

By smooth, it is meant that the surface roughness having a roughness expressed as the arithmetic mean deviation Ra of less than 0.8 μm.

By combining the striated contact surface S2 (the striated surface has a roughness greater than 500 μm) and the smooth contact surface S1 (with a roughness less than 0.8 μm), it is ensured that during the pivoting of the second part 12a, the friction part 14a slides against the first part 11a while remaining stationary vis-à-vis the second part.

As the friction part is elastically deformable along its radial directions, the closer the frusto-conical surface S3 of the pivot 13a is to the second part 12a, the more the friction part 14a expands radially.

This makes it possible to increase, on the one hand, the compressive force of the friction part 14a against the contact surface S1 (this contact surface S1 being here a form of revolution, more particularly a cylindrical surface with a central axis coinciding with the main axis A-A of the pivot) and on the other hand the compression force of the friction part 14a against the contact surface S2.

The greater these compression forces exerted by the pivot 13a on the friction part 14a, the greater the friction force generated by the friction part and opposing the orientation of the first and second parts 11a, 12a one relative to each other is important.

Throughout the pivoting of the second part 12a vis-à-vis the first part 11a, this friction part 14a remains in contact against the contact surfaces S1, S2 which makes it possible to always maintain a friction opposing this swivel.

The user perceives a pivoting brake which is relatively homogeneous throughout the pivoting.

When the expected pivoting position of the second part 12a vis-à-vis the first part 11a is reached, then this expected position is maintained as soon as the user stops pivoting the second part.

Thus, once the expected orientation position is reached, the user does not have to perform any action to maintain the position adjustment of the branch.

Preferably, said pivot 13a and second part 12a are assembled together in a fixed manner to pivot together relative to first part 11a during pivoting of second part 12a relative to first part 11a along said main axis A-A.

Thus, during the life of joint 1a, there is a very low risk that the pivot will separate from the rest of the joint.

For this, the pivot 13a has an external thread 13a1 and the second part 12a has an internal thread 12a1 complementary to said external thread of the pivot 13a.

The external thread of the pivot engages in the internal thread of the second part to fix the pivot by screwing into the second part. By screwing the pivot into the second part, the user can adjust the intensity of the desired friction torque to oppose the rotation of the second part with respect to the first part.

The pivot 13a is preferably arranged to always be at a distance from the internal surface of the first passage 11a3.

As illustrated in Figures 3 to 5b, the first terminal end of the second part 2a preferably has an outer surface in the form of a portion of a right cylinder with the axis of the cylinder coinciding with the main axis A-A of the pivot 13a.

Preferably, said internal recess 11a1 of first part 11a is partly delimited by a portion of straight cylindrical surface complementary to said outer surface in the form of a straight cylinder portion of the first terminal end of second part 12a.

In order to limit the space between the first and second parts and thus minimize the risk of deformation of the pivot by axial displacement of the second part with respect to the first part, the straight cylindrical surface portion delimiting the internal recess 11a1 of the first part 11a is placed against or at a distance from the right cylinder portion of the first terminal end of the second part. This distance is strictly less than 1 tenth of a millimeter, preferably strictly less than 0.5 tenth of a millimeter.

When it is used to articulate the branch to the frame, the first part 11a of the joint is fixedly assembled to the frame 3 and the second part 12a of the joint is fixedly attached to the first branch 2a.

Preferably, the first part 11a has first and second parts secured together by a rigid assembly (for example by gluing or by welding).

The first part of the first part 11a is in the form of a hollow right cylindrical shape and truncated on the outside to define an external facet Fx against which the second part of this first part 11a is assembled.

As illustrated on the , the first part of the first part 11a contains said internal recess 11a1, said lateral opening 11a2 and said first passage 11a3 through which said pivot 13a passes.

The second part 11a4 of the first part 11a forms a rod 11a4 to connect this first part of the joint 1a to the said mount 3.

As illustrated in Figures 1 or 3, this rod 11a4 can be curved, for example L-shaped or V-shaped.

The second part 12a of a given joint can be fixedly attached to a given branch 2a:
- either because this second part is shaped as an ear support branch, which makes it possible to obtain a second part fixedly attached to the branch (in this case, the second part and the ear support branch form a single and same part);
- either because this second part 12a is fixedly assembled to the branch 2a via an assembly, for example welding or gluing or a reversible assembly (in the latter case, the second part and the branch are manufactured separately then assembled together) .

In the present case, the second part 12a constitutes an ear support branch 2a, one of the terminal ends of which is placed in said recess of the first part.

As indicated above, apart from the difference in symmetry, the second joint 1b is identical to the first joint 1a.

Thus, as illustrated in the , when the second joint 1b is used to connect the second branch to the frame 3, its first part 11b is fixedly assembled to the frame 3 and its second part 12b is fixedly secured to the second branch 2b.

The friction part 14a is preferably made of PEEK, that is to say polyetheretherketone which has advantages in terms of hardness, longevity and durability.

For reasons of mechanical strength and resistance to corrosion, the pivot 13a is preferably made of stainless steel.

As we understand on the , the joint according to the invention can be assembled in three successive operations which are respectively identified by circled numbers 1, 2 and 3.

The first step consists of inserting the second part 12a into the first part.

The second operation consists of inserting the friction part 14a into the first part 11a.

The third operation consists of inserting the pivot to articulate the first and second parts together and tighten the friction part 14a.

The invention is not limited to the examples described above and it encompasses all variants falling within the scope defined by the claims.

In particular, while in the embodiment illustrated in Figures 3 to 5b, the friction part 14a is in direct contact against a surface of the pivot to be compressed axially along the main axis of the pivot, between the pivot and the second part , it is also possible for the friction part to be in direct contact against flat friction surfaces belonging to the first and second parts.

In this case, this friction part is between these flat surfaces and the pivot does not exert any function of axial compression of the friction part and it only exercises a function of centering the second part with respect to the first part. .

In this embodiment, the internal recess of the first part and the second part together define a reception space for the friction part, the height of which, measured in a direction parallel to the main axis A-A of the pivot, is less than a height of the friction part measured when this friction part is located outside of said recess of the first part.

The friction part is here elastically deformable along a main direction of deformation which is parallel to the main axis A-A of the pivot so that this friction part exerts an elastic force opposing the approach of the contact surface belonging to the first part vis-à-vis the contact surface belonging to the second part.

In this alternative mode, this elastic force exerted by the friction part against the planar contact surfaces of the first and second parts exists throughout the pivoting of the second part with respect to the first part and it is not in nothing dependent on the axial position of the pivot in the direction parallel to the axis A-A of the pivot.

Thus, whatever the orientation position of the second part, there is always a friction torque opposing the pivoting of the second part, this torque being independent of a tightening of the pivot.

In this mode, the friction piece preferably has the shape of a Belleville washer.

Claims (17)

Articulation (1a) to form an articulated connection between a branch (2a) and a frame (3) to support a pair of optical lenses (4a, 4b), the articulation (1a) comprising:
- a first part (11a) having an internal recess (11a1) and a lateral opening (11a2) extending from said internal recess (11a1) to a zone external to the first part (11a);
- a second part (12a) extending from the zone external to the first part (11a) to said internal recess (11a1) of the first part (11a) passing through said lateral opening (11a2); And
- a pivot (13a) extending along a main axis of the pivot (AA), this pivot (13a) passing through a first passage (11a3) formed in the first part (11a) and through a second passage (12a3) formed in the second part (2a) for producing a pivot connection between these first and second parts (11a, 12a) around the said main axis (AA) of the pivot (13a), characterized in that the joint (1a) comprises a friction part (14a) positioned inside at least one of said first passage (11a3) and said internal recess (11a1) of the first part (11a), the friction part (14a) forming an interface between a surface of contact (S1) belonging to said first part (11a) and a contact surface (S2) belonging to said second part (12a) to oppose, by friction of this friction part (14a) against at least one of said contact surfaces (S1, S2), on pivoting of said second part (12a) vis-à-vis the first part (11a) around said main axis (AA) of the pivot (13a). Articulation according to Claim 1, in which the said pivot (13a) and the second part (12a) are assembled together in an integral manner in order to pivot together with respect to the first part (11a) during a pivoting of the second part (12a ) relative to the first part (11a) along said main axis (A-A) of the pivot (13a). Articulation (1a) according to any one of Claims 1 or 2, in which the pivot (13a) has an external thread (13a1) and the second part (12a) has an internal thread (12a1) complementary to the said external thread of the pivot ( 13a), the external thread of the pivot being engaged in the internal thread of the second part to fix the pivot by screwing into the second part. Articulation according to any one of Claims 1 to 3, in which the friction piece (14a) is elastically deformable along radial directions perpendicular to the main axis (A-A) of the pivot (13a) so that, in response to a compression of the friction part (14a) between the pivot (13a) and the second part (12a), the friction part (14a) expands radially and comes into compression against the said contact surface (S1) belonging to the said first part (11a), this contact surface (S1) belonging to the first part being a surface of revolution whose main axis of revolution coincides with said main axis (A-A) of the pivot (13a). Articulation according to Claim 4, in which the pivot (13a) comprises an outer surface (S3) of frusto-conical shape at least partially positioned in a central passage (14a1) of the friction piece (14a), this outer surface (S3 ) of truncated-conical shape extending between a base (B1) of the truncated-conical and a narrow end (B2) of the truncated-conical, the narrow end (B2) of the truncated-conical being located closer to the second part (12a) than the base (B1) of the truncated-conical shape, this outer surface (S3) of truncated-conical shape resting against the friction part (14a) so as to force the radial expansion of the friction. Articulation according to Claim 4, in which the friction part (14a) is a part of revolution whose axis of revolution coincides with the said main axis (A-A) of the pivot (13a). Articulation according to any one of Claims 1 to 5, in which the friction part is an elastically deformable washer in directions radial to the axis of revolution of the friction part. Articulation according to Claim 7, in which the friction part (14a) is arranged between a shoulder (EP) of the said pivot and the said contact surface (S2) belonging to the said second part (12a), this contact surface (S2) belonging to the second piece being a flat surface. Articulation according to any one of Claims 1 to 8, in which the contact surface (S2) belonging to the said second part (12a) has a roughness expressed as the arithmetic mean deviation Ra greater than 500 µm. Articulation according to any one of Claims 1 to 9, in which the contact surface (S2) belonging to the said second piece (12a) is grooved to increase the friction against the friction piece (14a). Articulation according to at least one of Claims 9 or 10, in which the contact surface (S1) belonging to the said first part (11a) is smooth. Articulation according to any one of Claims 1 to 11, in which the said lateral opening (11a2) of the first part (11a) is delimited by first and second flat surfaces (Sp1, Sp2) of this first part which are mutually parallel , the second part having an upper flat surface (Ssup) and a lower flat surface (Sinf) which are formed on either side of the second part and are parallel to each other, the upper flat surface of the second part resting against the first flat surface (Sp1) of the first part (11a) and the lower flat surface of the second part being opposite the second flat surface (Sp2) of the first part. Articulation according to any one of Claims 1 to 12, in which the second part (12a) constitutes an auricular support branch (2a) of which a first of the terminal ends is placed in the said recess of the first part. Articulation according to Claim 13, in which the first terminal end of the second part (2a) has an external surface in the form of a portion of a right cylinder with the axis of the cylinder coinciding with the main axis (A-A) of the pivot (13a). Articulation (1a) according to any one of Claims 1 to 14, in which the first part (11a) has first and second parts fixed together by a rigid assembly, the first part of the first part containing the said internal recess (11a1 ), said lateral opening (11a2) and said first passage (11a3) through which passes said pivot (13a) and the second part of the first part forming a rod (11a4) to connect this first part of the articulation (1a) to said mount (3) for supporting a pair of optical lenses (4a, 4b). Articulation according to any one of claims 1 to 15, in which said friction piece (14a) is made of PEEK. Optical device (0) comprising a mount (3) for supporting a pair of optical lenses (4a, 4b) and comprising first and second branches (2a, 2b), characterized in that the first branch (2a) is articulated vis- vis-à-vis the frame (3) via a first articulation (1a) according to any one of claims 1 to 16 and in that the second branch (2b) is articulated vis-à-vis the frame (3) via a second joint (1b) according to any one of claims 1 to 16, the first part (11a) of the first joint (1a) being fixedly assembled to the frame (3), the second part (12a) of the first joint (1a) and the first branch (2a) being fixedly fastened together, the first part (11b) of the second articulation (1b) being fixedly assembled to the frame (3), the second part (12b) of the second articulation ( 1b) and the second branch (2b) being fixedly fastened together.