EP0439381B1 - Rotation brake between two concentric parts and lipstick case or similar comprising such a brake - Google Patents

Abstract

Device comprising a collar (10a) whose annular base, fixed to the inner member (4a), is extended by a plurality of lugs (9a) which are resiliently deformable radially and whose free ends come into frictional contact within a cylindrical bearing solidly attached to the outer member (6a).

Description

The present invention relates to the small mechanical industry, more particularly in the field of packaging in rotating cases of stick substances such as cosmetic products, in particular lipstick, pharmaceutical products, glues, and household cleaning products.

In rotating cases of the lipstick mechanism type, it is desirable to introduce rotational braking means in order to avoid inadvertent movements of the stick during its use or during transport. For this, use was made of local friction between the two concentric sheaths with the interposition of a compressed free ring, as described in document FR-A-1 417 277, with deformation of the sheaths or friction of the bucket-slider holder stick against the sheath which surrounds it as described in the document FR-A-1 501 043. These conventional solutions have drawbacks, in particular irregularities in efficiency resulting both from the molding tolerances of the sheaths and from the slider bucket as well as from the nature of the plastic in which they are molded and the choice of which is imposed by the mechanical stresses to which they are subjected as well as by their ease of molding in large series and their cost.

There are also known rotation locking devices, which may include crowns provided with elastic teeth (US-A-2,482,368; FR-A-2,459,936) intended not to regulate and brake the relative rotation of rotary members. but to block this rotation.

The invention aims to overcome the drawbacks of conventional braking means thanks to a flexible device interposed between two concentric rotary members, which it tolerates differences in play as well as possible ovalizations. Small dimensions, it can be made of material of appropriate specific mechanical qualities, possibly more expensive than that of the rotary members, without increasing the cost price of the assembly. Its manufacture and assembly in large series present no particular difficulty. In addition, the braking efficiency can be adapted to each case considered, with the same standardized device.

The subject of the invention is a device for braking in rotation between two concentric members, according to claim 1 appended, the preamble of which is based on document FR-A-1 417 277.

• Chacune des extrémités flexibles des pattes peut présenter vers l'extérieur un renflement formant frottoir;
• L'organe intérieur peut présenter une portée annulaire externe limitant le débattement centripète des pattes sur une partie de leur longueur à partir de la base et les incurvant éventuellement vers l'extérieur;
• La base de la couronne peut être assujettie sur l'organe interne par encliquetage d'au moins une protubérance annulaire de l'un dans une rainure complémentaire de l'autre;
• Au moins deux rainures décalées axialement peuvent être offertes à au moins une protubérance;
• De même, au moins deux protubérances annulaires décalées axialement peuvent être offertes à au moins une rainure;
• Protubérance et rainure correspondante peuvent avoir une forme tronconique s'évasant en direction des pattes;
• La base de la couronne peut être calée en rotation sur l'organe interne par l'association d'au moins une nervure parallèle à l'axe de l'une insérée dans une rainure correspondante de l'autre;
• Au moins quelques pattes peuvent être sécables à volonté à leur base;
• Le matériau de la couronne peut être d'une dureté différente de celui de la portée de l'organe externe;

According to various advantageous constructive provisions:

• Each of the flexible ends of the legs can have a bulge outwardly forming a rub;
• The internal member may have an external annular bearing limiting the centripetal movement of the legs over part of their length from the base and possibly bending them outwards;
• The base of the crown can be secured to the internal member by snapping on at least one annular protuberance of one in a groove complementary to the other;
• At least two axially offset grooves can be offered to at least one protuberance;
• Likewise, at least two axially offset annular protrusions can be offered to at least one groove;
• The protuberance and corresponding groove may have a frustoconical shape which widens in the direction of the legs;
• The base of the crown can be locked in rotation on the internal member by the association of at least one rib parallel to the axis of the one inserted in a corresponding groove on the other;
• At least some legs can be split at will at their base;
• The material of the crown may be of a different hardness than that of the scope of the external member;

The invention also relates to a case, for lipstick or other stick product, with a rotary mechanism for axial translation of the stick carried by a bucket with radial lugs cooperating with a double helical groove dug in a sheath and with a longitudinal slot another concentric and respectively rotary sheath, case characterized in that it comprises a braking device according to one of claims 1 to 10, the crown of which is secured to the base of the internal sheath of the case, the legs rubbing inside a marginal part of the base of the outer sheath or of an outer sheath secured to the outer sheath and extending it.

The invention can be more easily understood by examining and detailed description of the appended drawings which represent two embodiments of the invention, chosen simply by way of example from the numerous embodiments, adaptations and variants of the invention accessible to an experienced technician.

• la figure 2 est une vue schématique, en élévation et pour moitié en coupe axiale de l'étui de la figure 1;
• la figure 3 est une vue schématique, en élévation et en coupe axiale d'un second mode de réalisation d'un étui de rouge à lèvres suivant l'invention, dont les moitiés droite et gauche représentent deux dispositions de la couronne de freinage correspondant à deux valeurs de freinage différentes;
• la figure 4 est une vue schématique de détail, à plus grande échelle, en élévation et en coupe axiale, du dispositif de freinage adaptable de l'étui de la figure 3;
• la figure 5 est une vue schématique, en élévation et en coupe axiale, de la base de l'organe interne de l'étui de la figure 3;
• la figure 6 est une vue schématique, en élévation et en coupe axiale, de la couronne de l'étui de la figure 3;
• la figure 7 est une vue schématique, en élévation et en demi-coupe axiale, des deux organes rotatifs de l'étui de la figure 3;
• la figure 8 est une vue schématique, en élévation et en demi-coupe axiale, d'une première disposition de la couronne et de la base de l'organe intérieur de l'étui de la figure 3, pour un freinage faible; et,
• la figure 9 est une vue analogue à celle de la figure 8 d'une seconde disposition à freinage plus fort.

In these drawings:
Figure 1 is a schematic view, in exploded perspective, of a first embodiment of a lipstick case according to the invention;

• Figure 2 is a schematic view, in elevation and half in axial section of the case of Figure 1;
• FIG. 3 is a schematic view, in elevation and in axial section of a second embodiment of a lipstick case according to the invention, the right and left halves of which represent two arrangements of the braking ring corresponding to two different braking values;
• Figure 4 is a schematic detail view, on a larger scale, in elevation and in axial section, of the adaptable braking device of the case of Figure 3;
• Figure 5 is a schematic view, in elevation and in axial section, of the base of the internal member of the case of Figure 3;
• Figure 6 is a schematic view, in elevation and in axial section, of the crown of the case of Figure 3;
• Figure 7 is a schematic view, in elevation and in axial half-section, of the two rotary members of the case of Figure 3;
• Figure 8 is a schematic view, in elevation and in axial half-section, of a first arrangement of the crown and the base of the inner member of the case of Figure 3, for weak braking; and,
• Figure 9 is a view similar to that of Figure 8 of a second arrangement with stronger braking.

In these figures, the corresponding elements are designated by the same reference numerals, possibly assigned an index. The dimensions and the respective proportions of these elements may not be respected in order to make the drawings more legible.

The lipstick case shown in FIGS. 1 and 2 essentially comprises a cursor cup 1 lipstick stick holder having two radial lugs 2 which slide, through longitudinal slots 3, 3 a of a tubular sheath internal 4, in helical grooves 5.5a of an external sleeve 6 secured to an open tubular case 7. The sleeve 6 rotates freely around the sheath 4 and the base of the case 7 projects below the base of the sleeve 6, thus providing an annular space and constituting a smooth cylindrical surface for the friction of the swollen ends 19 of legs 9 elastically externally curved and radially deformable, coming from the base of a crown 10, inserted around the base of the sheath 4, as shown in FIG. 2. The base of the crown 10 has longitudinal grooves 11, 11 a which cooperate with ribs 12, 12 a from the base of the sheath 4 for setting the crown 10 in rotation on the internal sheath 4. An annular flange 13 at the end of the sheath 4 axially wedges the crown 10. At the other end of the sheath 4, another split annular rim 14 fits elastically on the corresponding end of the sleeve 6 to wedge it axially, in cooperation with the ends 19 of the tabs 9, opposite.

Thus, when the various elements of FIG. 1 are assembled, as shown in FIG. 2, and the sheath 4 is rotated relative to the sleeve 6, the bucket 1 moves axially in the grooves 3, 3 a , the crown 10 is driven by the sheath 4 and the bulged outer ends 19 of its legs 9 come rub elastically inside the base of the case 7 secured to the sleeve 6, thus creating a soft and regular friction practically insensitive to ovalizations and differences in usual dimensions inevitable in parts molded in series.

If a lower friction is desired, it suffices to break at their base some of the legs 9, preferably distributed regularly.

It is advantageously possible to mold the sheath 4, and the sleeve 6 of polystyrene or polypropylene, the cup 1 of polystyrene, the crown 10 of acetal resin, and the case 7 of polystyrene. It is obviously possible to use any other suitable suitable plastics material, and their qualities can be modified by adding conventional fillers such as silicone, fiberglass, molybdenum sulfide, glass microbeads, polytetrafluoroethylene, in particular to improve or lessen their resistance to friction or their elasticity. The case 7 can also be made of metal, in particular of light or copper alloy.

The second embodiment of the lipstick case shown in FIGS. 3 to 9 comprises the same elements as that of FIGS. 1 and 2: an internal sheath 4 a , a sleeve 6 a , a case 7 a , a crown 10 a . To simplify the drawing, the stick-holder bucket similar to bucket 1 in FIGS. 1 and 2 has not been shown.

This second embodiment of Figures 3 to 9 differs from that of Figures 1 and 2 in that the base of the sheath 4 has two ribs 15, 15 a annular, of triangular section widening from the end of the base of the sheath 4, axially offset from one another and of an annular bearing 16. An annular rib 17 cooperates with the opposite flange 14 a of the sheath 4 a to keep the sleeve 6 a in free rotation, wedged axially around the sheath 4 a . The ribs 15, 15 a of the base of the sheath 4 a cooperate with snap-fastening with internal grooves 18, 18 a of the base of the crown 10 a to secure the crown of the sheath in two positions illustrated in FIGS. 8 and 9 and indicated respectively in solid lines and in dotted lines in FIG. 4.

When the crown 10 a is not very depressed on the base of the sheath 4 a , the two ribs 15, 15 a being engaged in the grooves 18, 18 a (FIG. 8), its legs 9a are not or only slightly pushed radially outwardly by the bearing surface 16 and their free ends 19 a deviate radially from the external wall of the sheath 4 a by a distance x1 slightly greater than the distance x (FIG. 7) separating the external wall of the sheath 4 a from the wall internal of the case 7a, which provides a smooth braking.

On the other hand, when the crown 10 a is pressed further onto the base of the sheath 4 a , the rib 15 a being alone engaged with the groove 18 (FIG. 9), and the base of the legs being relatively distant from the bearing surface 16, the lugs 9a are pushed radially outwardly by the bearing 16 at a distance x2 greater than distance x1, which provides a stronger braking, the lugs 9 a pressing more strongly on the inner wall of the base of the case 7a .

Thus, with the same parts, a simple adjustment of the machine to press more or less the crown on the base of the sheath during the assembly of the elements, makes it possible to obtain at will a smoother or stronger braking at the rotation of the sheath 4 a in the sleeve 6 a .

The elasticity of the legs of the crown and, consequently, the intensity of braking also depends on the free length of the legs, the short legs being more as rigid as the long legs, but also the size of their section, and also the width of their bearing surface.

A braking mechanism according to the invention does not require any lubrication, which is an advantage compared to conventional mechanisms.

Claims (11)

1. Device for rotational braking between two inner (4, 4a) and outer (6, 6a) concentric members adapted for rotation within one another, of a case for lipstick or other product in stick form, which comprises a collar (10, 10a) whose annular base is fixed to the inner member (4, 4a) characterized in that said base is extended by a plurality of lugs (9, 9a) which are resiliently deformable radially and only the free ends of which come into frictional and rotational contact within a cylindrical bearing solidly attached to the outer member (6, 6a).
2. Device according to claim 1, characterized in that each of the flexible ends (19) of the lugs (9) possesses, towards the outside, a swelling (19a) forming a friction means.
3. Device according to either of claims 1 and 2, characterized in that the inner member (4, 4a) possesses an outer annular bearing (16) limiting the centripetal movement of the lugs (9a) over part of their length, from the base, and bending them outwards if appropriate.
4. Device according to claim 3, characterized in that the base of the collar (10a) may be fixed on the inner member (4a) by snap-fitting of at least one annular protrusion (15, 15a) on the one into a complementary groove (18, 18a) on the other.
5. Device according to claim 4, characterized in that at least two axially offset grooves (18, 18a) are presented to at least one protrusion (15, 15a).
6. Device according to either of claims 4 and 5, characterized in that at least two axially offset annular protrusions (15, 15a, 17) are presented to at least one groove (13, 14, 14a, 18, 18a).
7. Device according to one of claims 4 to 6, characterized in that the corresponding protrusion (15, 15a) and groove (18, 18a) are of frustoconical shape, widening towards the lugs.
8. Device according to one of claims 1 to 7, characterized in that the base of the collar (10a) is keyed for rotation on the inner member (4a) by the association of at least one axis-parallel rib (12, 12a) on the one inserted into a corresponding groove (11, 11a) on the other.
9. Device according to one of claims 1 to 8, characterized in that at least some lugs are divisible at their base, as required.
10. Device according to one of claims 1 to 9, characterized in that the material of the collar (10) is of a different hardness from that of the bearing of the outer member (6).
11. Case (7, 7a) for lipstick or other product in stick form, having a rotary mechanism for the axial translatory movement of the stick carried by a cup (1) possessing radial pins (2) interacting with a double helical groove (5, 5a) cut in an outer sheath (6, 6a) and with a longitudinal slot (3, 3a) in inner sheath (4, 4a) which is concentric and undergoes relative rotation, which case comprises a braking device comprising the collar (10) whose annular base is fixed to the base of the inner sheath (4, 4a) of the case, characterized in that the braking device is made in accordance to one of claims 1 to 10, the ends of the lugs (9) making rotational frictional contact with the inside of a marginal portion of the base of the outer sheath (6, 6a) or of an outer sleeve (7, 7a) solidly attached to the outer sheath and prolonging the latter.

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