CN110891457B

CN110891457B - Cam mechanism, in particular for a cosmetic product applicator

Info

Publication number: CN110891457B
Application number: CN201880047464.4A
Authority: CN
Inventors: 萨温·勒菲弗尔; 法兰西斯·戈捷; 安托万·比洛
Original assignee: Parfums Christian Dior SA
Current assignee: Parfums Christian Dior SA
Priority date: 2017-07-20
Filing date: 2018-07-20
Publication date: 2022-02-25
Anticipated expiration: 2038-07-20
Also published as: WO2019016489A1; FR3069140A1; CN110891457A; FR3069140B1; EP3654800A1; EP3654800B1

Abstract

A cam mechanism (10) for a cosmetic applicator, the cam mechanism comprising a sheath (30) constrained to rotate with a stem (20) and to be slidable relative to the stem, a skirt (50) constrained to rotate with a sleeve (40) and to be slidable relative to the sleeve, a sleeve (40) constrained to rotate with a body (110) and to be slidable relative to the body (110). The sheath (30) cooperates with the skirt (50) such that rotation of the sheath relative to the skirt causes axial movement of the skirt (50) relative to the sheath (30), the sleeve (40) cooperating with the rod (20) and the sheath (30) such that rotation of the rod relative to the sleeve causes axial movement of the sleeve (40) relative to the rod (20), which movement causes the sheath (30) to slide relative to the rod (20).

Description

Cam mechanism, in particular for a cosmetic product applicator

Technical Field

The present disclosure relates to applicators used in the field of cosmetics, and more particularly to a cam mechanism that may be used in such applicators. However, such cam mechanisms may be used in other applications.

Background

In the field of cosmetic applicators, liquid or pasty product applicators are known, which comprise a body containing a product and a mechanism allowing the product to be expelled from the body through an opening provided in the body.

Such an applicator is described in document FR 928233. The mechanism disclosed in this document is a telescopic mechanism comprising three elements. A ring rotatably mounted with respect to the body of the applicator allows to drive in rotation a first of these elements, which in turn triggers in succession the rotation of the other two elements and expels the cosmetic product from the applicator.

However, it has been noted that a new type of cam mechanism is required.

Disclosure of Invention

To this end, the present disclosure relates to a cam mechanism, in particular for a cosmetic product applicator, comprising a stem, a sheath, a sleeve, a skirt and a body, wherein the sheath is rotationally fixed relative to the rod and slidable relative to the rod, the skirt is rotationally fixed relative to the sleeve and slidable relative to the sleeve, the sleeve being rotationally fixed relative to the body and slidable relative to the body, the sheath cooperating with the skirt, such that rotation of the sheath relative to the skirt causes axial movement of the skirt relative to the sheath, the sleeve cooperating with the rod and the sheath such that rotation of the rod relative to the sleeve causes axial movement of the sleeve relative to the rod, axial movement of the sleeve slidably drives the sheath relative to the rod in at least one direction.

A cam mechanism in the sense of the present disclosure is a mechanism that allows to convert a rotational movement into a translational movement or vice versa. As will be explained in detail later, in the present cam mechanism, more simply referred to as the "mechanism", the body, the rod, the sheath, the sleeve and the skirt are assembled such that rotation of the rod ultimately causes translation of the skirt.

The sheath is simultaneously rotationally fixed relative to the rod and configured to slide relative to the rod. Similarly, the skirt is simultaneously rotationally fixed relative to the sleeve and configured to slide relative to the sleeve. Finally, the sleeve is simultaneously rotationally fixed relative to the body and configured to slide relative to the body.

In the sense of the present disclosure, the axial direction is defined by the axis of rotation considered. The radial direction is a direction perpendicular to the axial direction and intersecting the axis. Similarly, an axial plane is a plane containing the axis, and a radial plane is a plane perpendicular to the axis.

In this mechanism, when the rod is rotated relative to the body and thus relative to the sleeve, the sleeve and sheath are driven into axial movement relative to the rod, thereby creating a first deployment. At the same time, rotation of the rod causes rotation of the sheath, since the sheath and the rod are rotationally fixed to each other. Rotation of the sheath in turn causes axial movement of the skirt, thereby creating a second deployment.

Thus, unlike prior art devices, the various portions of the cam mechanism according to the present disclosure deploy simultaneously, which allows for distributing forces between the portions and limits their wear. In addition, the deployment of the mechanism, as measured by the axial velocity of the skirt relative to the stem, is faster than in prior art devices, for example. In addition, the mechanism is particularly compact and allows for a regular dispensing flow rate when used in a cosmetic applicator due to the simultaneity of the two deployments.

In some embodiments, the stem, the sheath, the sleeve, the skirt, and the body are coaxial. The cam mechanism may be a telescopic mechanism configured to be expanded in the axial direction. In some embodiments, the stem, sheath, skirt, sleeve and body are disposed radially around one another, in particular in that order.

The rod, sheath, sleeve, skirt and body do not necessarily have rotational symmetry, at least due to the rotational fixing means that the rod, sheath, sleeve, skirt and body may have.

In some embodiments, the stem includes threads that mate with complementary threads of the sleeve. A thread, in the sense of the present disclosure, may mean either a male or a female thread, sometimes referred to as tapping. It will therefore be appreciated that the male or female thread of the rod mates with a complementary female or male thread of the sleeve respectively.

Similarly but independently, in some embodiments, the skirt includes threads that mate with complementary threads of the sheath.

According to a variant, for example, an alternative to the thread may comprise at least one radial projection of the stem, which fits in a helical groove of the sleeve, for example. These elements may be reversed.

In some embodiments, the sleeve comprises a tubular body and a transverse wall extending transversely with respect to the tubular body, the transverse wall comprising the complementary thread of the sleeve. The tubular body may extend in an axial direction about an axis. The complementary threads may be provided on the outer periphery of the wall or in the inner aperture of the wall.

In some embodiments, the sheath is configured to bear axially on a transverse wall of the sleeve. Thus, in the axial movement of the sleeve, the transverse wall exerts a force on the sheath, at least in one direction, which force slidably drives the sheath in the axial direction.

In some embodiments, the means for rotationally fixing the rod relative to the sheath and/or the means for fixing the skirt to the sleeve and/or the means for fixing the sleeve to the body comprise radial projections that fit in axial slots. The axial grooves may be grooves, notches, etc. The axial slot may extend substantially axially. The protrusions may be ribs, tabs, lugs, or the like. The protrusion may protrude radially toward the axial groove. The axial grooves thus form guides for the axial sliding of the projections, while limiting the radial travel of the projections, thus ensuring the rotational fixing.

The present disclosure also relates to a liquid or pasty product applicator, in particular a cosmetic product applicator, comprising a reservoir capable of containing said product and a cam mechanism as previously described. The reservoir may be formed between a skirt of the cam mechanism and a wall of an applicator that includes an opening for dispensing the product. Movement of the skirt relative to the stem can reduce the size of the reservoir and thus cause the product to be dispensed through the opening.

Thus, in some embodiments, the applicator comprises an applicator tip equipped with an opening communicating with the interior of the reservoir, and the cam mechanism is housed at an end of the applicator opposite the opening.

In some embodiments, the skirt is of a piston configured to push the product out of the reservoir.

In some embodiments, the body of the cam mechanism forms the body of the applicator defining the reservoir. In other words, in these embodiments, the body of the applicator and the body of the cam mechanism are one component. Alternatively, the body of the cam mechanism may be a different part to the body of the applicator; in these embodiments, the cam mechanism may be housed in the body of the applicator, the body of the cam mechanism being prevented from rotating or even moving axially relative to the body of the applicator.

In some embodiments, the applicator includes a base rotatably mounted relative to the body, and the stem is rotationally fixed relative to the base. Thus, rotation of the base causes rotation of the lever and subsequent deployment of the cam mechanism. The axial position of the stem relative to the base and/or relative to the body may be fixed.

Drawings

The invention and its advantages will be better understood by reading the following detailed description of embodiments of the invention, given as non-limiting examples. The description makes reference to the accompanying drawings, in which:

fig. 1 is a perspective view of an applicator according to one embodiment;

fig. 2 is a longitudinal cross-sectional view of the applicator of fig. 1, with the cam mechanism fully deployed;

FIG. 3 is a sectional view taken along the plane III-III of FIG. 2;

FIG. 4 is an exploded perspective view of some components of the mechanism according to the embodiment of FIG. 2;

fig. 5 is a view similar to fig. 2 with the cam mechanism fully retracted.

Detailed Description

In the present disclosure, the terms "upper", "lower", "top" and "bottom" are to be construed in a relative sense only with reference to the accompanying drawings. They allow two substantially opposite positions to be distinguished without predicting the orientation of the device in space. In particular, in the general sense of this term, the line connecting the "top" point and the "bottom" point is not necessarily perpendicular.

A cam mechanism and an applicator including such a mechanism according to one embodiment are shown in fig. 1-4. Fig. 1 is a perspective view of a liquid or pasty product applicator, in particular a cosmetic product applicator 100 of the type such as lipstick, lip gloss, cream, lip gloss, concealer, foundation, eye shadow and the like. As shown in the sectional views of fig. 2 and 3, the applicator 100 comprises a body 110, here a substantially tubular body, which may have rotational symmetry about an axis X. Here, the axis X defines an axial or longitudinal direction. The body forms a reservoir capable of containing the product. Optionally, the body 110 is provided at one of its ends (here, its upper end) with an applicator tip 112, which may be formed integrally with the body 110 or alternatively by a separate part fixed to the body 110. The shape of the tip allows to optimize the application of the product. In this case, the tip 112 has an inclined outer surface 113, which is inclined with respect to the axis X of the applicator. Optionally, the beveled outer surface 113 may be textured or made of another material that is more comfortable to the touch, such as being molded onto the tip 112.

The product is dispensed through the opening 114 onto the applicator tip 112. The opening 114 opens into the applicator tip 112, and in particular to the outer surface 113, and is in fluid communication with the product reservoir.

To push the product contained in the reservoir through the opening 114, the applicator 100 includes a cam mechanism 10. As previously noted, cam mechanism 10 includes a rod 20, a sheath 30, a sleeve 40, and a skirt 50. In fig. 2 and 3, the cam mechanism 10 is shown fully deployed.

As shown, the stem 20 is substantially rectilinear and extends here along the axis X of the applicator. In this case, the rod 20 is a solid rod, but may also be provided hollow. The rod 20 comprises a thread 22, which in this case is a male thread. The thread 22 may be provided on the outer circumference of the rod 20. In the present embodiment, the thread 22 extends in the axial direction over substantially the entire length of the rod 20. However, for example, the rod 20 may comprise a non-threaded portion at its upper end so as to form a stop and prevent the elements cooperating with the thread 22 from disengaging therefrom.

In addition, the stem 20 comprises at least one axial groove, in this case two diametrically opposed grooves 24. The groove 24 extends substantially axially. The groove 24 is recessed toward the interior of the rod 20. As can be seen in fig. 3 and 4, the groove 24 interrupts the thread 22. However, since they are radially recessed with respect to the thread 22, the grooves 24 do not prevent the rotation of the element cooperating with the thread 22. Alternatively, the cross-section of the rod 20 may have an elliptical shape, the thread 22 being provided at least on the curved wall of the ellipse.

Further, typically one of the ends of the rod 20 (e.g., the lower end thereof) may be assembled to the base 26. In this case, the base 26 comprises a substantially circular disk-shaped base plate 27, from which disk-shaped base plate 27 a border 28 protrudes, which border is here substantially cylindrical. The border 28 protrudes from the base plate 27 on the same side as the stem 20. In this embodiment, the stem 20 and the boundary 28 are each substantially orthogonal to the base plate 27.

In this embodiment, the stem 20 and the base 26 are made in one piece. However, the stem 20 and the base 26 may form two separate components assembled to one another.

The sheath 30 is substantially cylindrical, here with a circular cross section, and in particular coaxial with the rod 20. In this embodiment, the sheath 30 is placed radially outside the rod 20, that is, radially around the rod 20. The sheath 30 includes threads 32, which in this case are male threads. Threads 32 may be provided on the outer periphery of sheath 30. In the present embodiment, the thread 32 extends in the axial direction over substantially the entire length of the sheath 30. However, in this embodiment, the sheath 30 includes a support portion 36 at one of its ends (here, its lower end). Here, the outer cross section of the support portion 36 is larger than the outer cross section of the thread 32. Also, for example, sheath 30 may include an unthreaded portion at its end opposite support 36 to form a stop and prevent elements mated with threads 32 from disengaging therefrom.

Also here, the radially inner surface of the sheath 30 is an unthreaded smooth surface having a diameter greater than the diameter of the thread 22. Thus, the rod 20 and the sheath 30 can slide relative to each other, in particular in the axial direction.

However, the sheath 30, in particular the radially inner surface, comprises at least one radial protrusion, in this case two diametrically opposed ribs 34. The ribs 34 extend substantially axially. The ribs 34 project towards the inside of the sheath 30, that is to say radially towards the stem 20. As shown in fig. 3, ribs 34 of sheath 30 fit into grooves 24 of rod 20. Thus, groove 24 and ribs 34 form a rotation prevention means whereby sheath 30 is rotationally fixed relative to rod 20, but sheath 30 remains free to translate relative to rod 20.

Here, the sleeve 40 is coaxial with the rod 20 and, in this embodiment, is placed radially outside the rod 20 and the sheath 30, that is, radially around the rod 20 and the sheath 30. As shown, the sleeve 40 includes a tubular body 41 and a transverse wall 46 extending transversely with respect to the tubular body 41. The tubular body 41 is substantially cylindrical about the axis X, having a circular cross-section. The inner diameter of the tubular body 41 may be greater than the outer diameter of the rod 20 and sheath 30.

The transverse wall 46 extends substantially perpendicularly with respect to the tubular body 41, in this case towards the inside of the tubular body 41. In this case, the transverse wall 46 comprises an aperture provided with a thread 42 on its circumference. The aperture may be formed substantially centrally in a transverse wall 46 forming an annulus around the aperture.

The threads 42 of the sleeve are complementary threads to the threads 22 of the rod 20. Thus, the threads 22 and the complementary threads 42 are configured to cooperate with one another. In this case, the complementary thread 42 is a female thread. In the present embodiment, the complementary thread 42 extends in the axial direction substantially over the entire thickness of the transverse wall 46. Thus, the thread 22 of the rod and the complementary thread 42 of the sleeve form a cam arrangement by which rotation of the rod 20 relative to the sleeve 40 causes axial movement of the sleeve 40 relative to the rod 20. In particular, rotation of the stem 20 relative to the body 110 causes axial movement of the sleeve 40 relative to the body 110, due to the fact that the sleeve 40 is prevented from rotating relative to the body 110 but slides relative to the body 110 (as will be seen later).

In addition, the sleeve 40 includes at least one axial slot, in this case a notch 44 (see fig. 3 and 4). The cut-out 44 extends substantially axially.

As can be seen in fig. 2, the sheath 30 is configured to bear axially on a transverse wall 46 of the sleeve 40. In this case, the bearing 36 bears on the transverse wall 46. In this embodiment, the bearing is even here axially fixed relative to the sleeve 40 by clamping. Sheath 30 is thus translationally fixed relative to sleeve 40, but remains free to rotate relative to sleeve 40. Thus, the axial movement of the sleeve 40 drives the sheath 30 in at least one direction, here in both directions, in the same axial direction relative to the rod 20.

Here, the skirt 50 is coaxial to the sheath 30 and, in this embodiment, is placed radially outside the stem 20 and the sheath 30, that is to say, radially around the stem 20 and the sheath 30, and radially inside the sleeve 40, at least inside the tubular body 41.

Skirt 50 includes threads 52 on its inner surface. The threads 52 of the skirt are complementary threads to the threads 32 of the sheath 30. Thus, the threads 32 and the complementary threads 52 are configured to cooperate with one another. In this case, the complementary thread 52 is a female thread. In the present embodiment, the complementary thread 52 extends in the axial direction over substantially the entire length of the skirt 50. Thus, the threads 32 of the sheath and the complementary threads 52 of the skirt form a cam arrangement by which rotation of the sheath 30 relative to the skirt 50 causes axial movement of the skirt 50 relative to the sheath 30. In particular, rotation of sheath 30 relative to sleeve 40 causes axial movement of skirt 50 relative to sleeve 40 due to the fact that skirt 50 is prevented from rotating relative to sleeve 40 but slides relative to sleeve 40 (as will be seen later).

Further, here, the radially outer surface of the skirt 50 is an unthreaded, smooth surface having a diameter smaller than the inner diameter of the sleeve 40. Thus, the sleeve 40 and the skirt 50 are able to slide relative to each other, in particular in the axial direction.

However, the skirt 50, and in particular the radially outer surface, may comprise at least one radial protrusion, in this case a tab 54. The tabs 54 may be provided only on the lower portion of the skirt 50. The tabs 54 project towards the outside of the skirt 50, that is to say radially towards the sleeve 40. As shown in fig. 3, the tabs 54 of the skirt 50 fit within the notches 44 of the sleeve 40. Thus, the cut-outs 44 and tabs 54 form a rotation-inhibiting means whereby the skirt 50 is rotationally fixed relative to the sleeve 40, but is free to translate relative to the sleeve. Thus, in this embodiment, cam mechanism 10 is a telescoping mechanism, wherein rod 20, sheath 30, skirt 50, sleeve 40 and body 110 are coaxial and arranged radially around each other from the inside to the outside in that order. However, this order may be modified, at least reversed, as necessary from the details.

As mentioned above, when the rod 20 is rotated relative to the sleeve 40 from a retracted position (with reference to fig. 5) in which the rod 20, the sheath 30, the sleeve 40 and the skirt 50 are as close to each other as possible in the axial direction, the cooperation of the

threads

22,42 causes an axial movement of the sleeve 40 relative to the rod 20, which simultaneously causes an axial movement of the sheath 30 relative to the rod 20 via the transverse wall 46 and the bearing 36. Movement of the sheath 30 and the sleeve 40 relative to the stem 20 in the axial direction (in this case, in the direction D1 towards the top of the applicator 100) forms a first deployment.

At the same time, rotation of the stem 20 relative to the sleeve 40 causes a corresponding rotation of the sheath 30 via cooperation of the grooves 24 and ribs 34, while the skirt 50 is rotationally fixed relative to the sleeve 40 due to the engagement of the tabs 54 in the slots 44. Thus, sheath 30 is driven in rotation relative to skirt 50, which, due to the cooperation of

threads

32,52, causes axial movement of skirt 50. Axial displacement of skirt 50 relative to sheath 30 creates a second deployment.

Therefore, the structure of the telescopic mechanism allows the members of the cam mechanism 10 to be simultaneously doubly spread in the axial direction. This allows for regular spreading, thereby better controlling the dispensing of the product. Furthermore, this allows for a compact mechanism, thereby containing more product in a given volume.

As previously described, the body 110 of the cam mechanism 10 may form the body of the applicator 100. Preferably, the cam mechanism 10 may be disposed opposite the product dispensing opening 114.

In this embodiment, the body 110 is made of a transparent material, for example, copolyester or polycarbonate. In order to conceal a part of the cam mechanism 10, the body 110 may be covered by a cover element 115, in particular, which is opaque, extends in the axial direction, here in a substantially cylindrical manner. However, as can be seen in fig. 2, in this embodiment, a portion of skirt 50 is not covered by cover element 115. The portion may include text or ornamentation that is displayed to the user when the product is in use.

Here, the covering element 115 is mounted on a ring 116 fastened to the body 110 and bears on a shoulder 117 of the body 110. The covering element 115 may be made of metal, for example of aluminium, or of a thermoplastic material optionally coated with a metal coating. The cover element may be fixed by snapping, gluing, screwing or embedding. For example, a hoop 118 made of a thermoplastic material may at least partially surround the body 110 and/or the cover element 115. The ferrule 118 may be supported on the annular portion 116 of the body 110. The band 118 may be provided to allow the user to more easily grasp the applicator 100. Here, the ferrule 118 is an aesthetically pleasing element that also serves to secure the cap.

The applicator 100 may further include a base 120 rotatably mounted on the body 110, preferably at an end of the body 110 opposite the applicator tip 112 (in this case, the lower end of the body 110). The base 120, here a ring, may be assembled to the body 110 by methods known per se. In this case, the base 120 has the axis X of the applicator 100 as the axis of rotation. In this embodiment, the cuff 118 and chassis 120 are secured to one another.

The applicator 100 may also include a cap 130 configured to cap the applicator tip 112 and seal the applicator tip as appropriate. Sealing means (not shown) may be provided inside the cap 130 and/or at the interface between the cap 130 and the body 110, the cover element 115 or the collar 118, as the case may be.

The cam mechanism 10 may be mounted in the applicator 110 by: for example, base 26 is typically secured within base 120 by gluing, clamping, crimping, or the like, and rod 20 may be rotationally fixedly mounted with respect to base 120. Splines may be provided between the base 26 and the seat 120 for rotational drive and/or snaps may be provided for axial locking.

The sleeve 40 may be received in the body 110. In this embodiment, the applicator has a blocking means for blocking rotation of the sleeve 40 relative to the body 110. More specifically, the sleeve 40, here the lugs 48, projects radially from its outer surface and is configured to cooperate with the axial grooves 111 of the inner surface of the body 110. Thus, the sleeve 40 is prevented from rotating relative to the body 110. Subsequently, skirt 50, which is prevented from rotating relative to sleeve 40, is also prevented from rotating relative to body 110. Conversely, the rod 20, and thus the sheath 30, which is rotationally fixed relative to the rod 20, is rotatably mounted relative to the body 110. Thus, by simply rotating the mount 120 relative to the body 110, the rod 20 can be driven to rotate relative to the sleeve 40.

The skirt 50 has a piston element 58 at its upper portion, with which the skirt 50 forms a piston configured to push the product out of the reservoir. More specifically, the applicator 100 includes a reservoir formed in the body 110 between the applicator tip 112 and the skirt 50 (particularly the piston element 58). The piston element 58 encloses the body 110 transversely to its displacement axis X. For a better tight seal, the piston element 58 includes a scraper flange 56 disposed radially around an upper portion of the skirt 50. The squeegee flange 56 includes a generally frustoconical portion and is formed of a flexible material, such as polyethylene, low density polyethylene, or polypropylene. The squeegee flange 56 is press-fitted into the main body 110 so that its free end is folded on the main body 110 by an elastic restoring force. This force makes it possible not only to ensure a tight seal of the reservoir (here, in the upper part of the body 110 with respect to the scraper flange 56), but also to scrape the walls of the body 110 when the skirt 50 is moved upwards, thus minimizing the residual product not used in the reservoir.

For this purpose, the upper end of the piston element 58 may also be configured to at least partially substantially match the internal shape of the applicator tip 112. As mentioned before, this is aided by the fact that: here, the piston element 58 is prevented from rotating relative to the body 110 via the sleeve 40.

In another embodiment, the applicator 100 may be an applicator of a solid cosmetic product such as lipstick. The open end of the body 110 may be opened wider to allow the lipstick to be screwed out. Piston member 58 may include a cup or any other suitable device for holding a solid cosmetic product. In such embodiments, the squeegee flange is not useful.

Although the present invention has been described with reference to specific exemplary embodiments, modifications may be made to these examples without departing from the general scope of the invention as defined by the claims.

For example, here, although the axis of the cam mechanism 10 coincides with the axis X of the applicator 100, these axes may be different, parallel or non-parallel to each other.

More generally, various features of the various illustrated/referenced embodiments may be combined in yet other embodiments. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

Claims

1. A cam mechanism (10) comprising a rod (20), a sheath (30), a sleeve (40), a skirt (50) and a body (110), wherein the sheath (30) is rotationally fixed relative to the rod (20) and is slidable relative to the rod (20), the skirt (50) is rotationally fixed relative to the sleeve (40) and is slidable relative to the sleeve (40), the sleeve (40) is rotationally fixed relative to the body (110) and is slidable relative to the body (110), the sheath (30) cooperates with the skirt (50) such that rotation of the sheath (30) relative to the skirt (50) causes axial movement of the skirt (50) relative to the sheath (30), the sleeve (40) cooperates with the rod (20) and the sheath (30) such that rotation of the rod (20) relative to the sleeve (40) causes the sleeve (40) to move relative to the rod (20) (20) The axial movement of the sleeve (40) driving the sheath (30) slidingly with respect to the rod (20) at least in one direction (D1).

2. The cam mechanism according to claim 1, wherein the cam mechanism (10) is a cam mechanism (10) for a cosmetic product applicator (100).

3. The cam mechanism of claim 1, wherein the rod (20), the sheath (30), the sleeve (40), the skirt (50), and the body (110) are coaxial.

4. The cam mechanism according to claim 1, wherein the rod (20) comprises a thread (22) cooperating with a complementary thread (42) of the sleeve (40).

5. The cam mechanism according to claim 4, wherein the sleeve (40) comprises a tubular body (41) and a transverse wall (46) extending transversely with respect to the tubular body (41), the transverse wall (46) comprising the complementary thread (42).

6. The cam mechanism according to claim 5, wherein the sheath (30) is configured to bear axially on a transverse wall (46) of the sleeve (40).

7. The cam mechanism according to any of claims 1-6, wherein the skirt (50) comprises threads (52) that mate with complementary threads (32) of the sheath (30).

8. A cam mechanism according to any of claims 1 to 6, wherein the means for rotationally fixing the rod (20) relative to the sheath (30) and/or the means for fixing the skirt (50) to the sleeve (40) and/or the means for fixing the sleeve (40) to the body (110) comprise radial projections (34,54) which fit in axial slots (24, 44).

9. Applicator (100) for a liquid or pasty product, comprising a reservoir capable of containing the product and a cam mechanism (10) according to any one of claims 1 to 8.

10. Applicator according to claim 9, wherein the applicator (100) is an applicator for a cosmetic product.

11. Applicator according to claim 9, wherein the skirt (50) belongs to a piston configured to push the product out of the reservoir.

12. Applicator according to any one of claims 9-11, the body (110) of the cam mechanism (10) forming the body of the applicator (100) defining the reservoir.