Cosmetic applicator or assembly part thereof having a special threaded spindle drive

Abstract

The invention relates to a cosmetic applicator or assembly part, e.g., cartridge, for a cosmetic applicator, comprising a threaded spindle drive for displacing a lead consisting of a cosmetic substance relative to a lead casing tube that accommodates the lead (in whole or in part), wherein on the inner circumferential surface of the lead casing tube a thread is formed which interacts with the complementary thread of a lead holder that holds the lead (indirectly or directly) and translationally moves the lead holder together with the lead relative to the lead casing tube when one of the lead holders is rotated relative to the lead casing tube, characterized in that said thread of the lead casing tube is not a continuous thread, but consists of a number of thread islands that are spaced apart from one another (at least by more than just one thread groove), each of which has thread projections that extend by less than 121° in the circumferential direction and are designed and arranged such that the external thread of the lead holder is always in engagement with at least one thread island.

Description

[0001] COSMETIC APPLICATOR OR ASSEMBLY PART THEREOF WITH SPECIAL

[0002] Threaded spindle drive

[0003] The invention relates to a cosmetic applicator or an assembly part thereof, such as a cartridge, with a threaded spindle drive and a feature-based equipment according to the preamble of claim 1.

[0004] TECHNICAL BACKGROUND

[0005] Last but not least, eyeliners are produced as pencils, similar to those found in classic artist pencils. Traditional eyeliners are constructed like wooden pencils and must be sharpened at regular intervals. This results in a lot of wasted material.

[0006] For this reason, eyeliners are increasingly being used that have a mechanism that allows the lead to be pushed out of the surrounding and supporting sleeve of the pencil as far as is needed at the time. Then, if necessary, the lead only needs to be sharpened to enable it to draw a line of the desired thickness at the front. This means that keeping the eyeliner in use involves significantly less loss of material.

[0007] TECHNICAL PROBLEM

[0008] However, this gives rise to the problem that the lead of an eyeliner or similar pencil has to be pushed out of the pencil sleeve over a relatively long distance over the course of the product's lifespan. If a thread is used on the inner circumferential surface of the sleeve to generate the sliding movement, this has previously caused a considerable amount of manufacturing effort. For example, whenever the sleeve is injection molded, it is necessary to screw the sleeve out of the injection mold after the injection molding compound has solidified because the thread on the inner surface of the sleeve prevents a linear ejection movement. Such complex molding prevents short cycle times and also causes equipment expenditure, and therefore costs.

[0009] OBJECT OF THE INVENTION

[0010] Against this background, it is the object of the invention to provide a cosmetic applicator or an assembly unit thereof, for example a cartridge for refilling, which has a feed mechanism which works with a thread over a long distance, but can be formed more easily after the actual injection molding process than the previous endless threads which have to be unscrewed.

[0011] INVENTIVE SOLUTION

[0012] The solution according to the invention consists in a cosmetic applicator or an assembly part, for example a cartridge, for a cosmetic applicator having the features of claim 1.

[0013] Accordingly, a cosmetic applicator or an assembly part, such as a cartridge or a refill cartridge, for a cosmetic applicator is proposed, which has the features listed below. In the following, the term "cosmetic applicator" is used to represent the cosmetic applicator and the assembly part.

[0014] The cosmetic applicator according to the invention comprises a threaded spindle drive for displacing a lead made of cosmetic compound relative to a lead casing tube that completely or partially houses the lead. The lead casing tube can be the outermost tube, which the user also directly grasps with her hands when using the applicator.

[0015] Alternatively, but not preferred, the mine casing tube can also be a tube located further inside, which is, for example, covered or wrapped by a cartridge case, which has a certain design and decorative function.

[0016] A thread is formed on the inner circumferential surface of the mine casing tube. It interacts with the complementary thread of a mine holder that directly or indirectly holds the mine. Due to the thread interaction, the mine holder, along with its mine, is displaced translationally relative to the mine casing tube. The latter always occurs when the mine holder is rotated relative to the mine casing tube.

[0017] According to the invention, the thread of the mine casing tube is not a continuous thread. Nor is it a thread whose thread grooves or thread flanks extend uninterruptedly from the beginning to the end of the thread and are embedded in the surface of the mine casing tube.

[0018] Instead, a number of locally formed thread islands are provided, each spaced apart from one another on all sides, but preferably arranged along a helical line. Each of these thread islands consists of at least two, possibly three, helically extending parallel thread projections, enclosing at least one thread groove between them, which project radially inward beyond the inner surface of the mine casing tube.

[0019] In any case, a thread island is referred to as a location at which several thread projections are formed, which cooperate via the associated thread sleeve with similarly formed thread projections at another location, whereby each thread island is completely spaced from all other thread islands on all sides.

[0020] Typically, these thread projections extend less than 125°, preferably less than 95°, and ideally less than 65° in the circumferential direction of the lead casing tube. The thread islands are designed and arranged so that the external thread of the lead holder always engages with at least one thread island, regardless of the position of the lead holder along its intended displacement path.

[0021] Because only a very limited number of purely local thread engagements occur between the injection mold or its core and the lead cladding tube injected onto it, it is possible to pull the lead cladding tube off the mold core with its external thread, despite its internal thread, by simply exploiting the extensibility of the still warm, recently injected plastic. With the right design, it can be pushed out, i.e. the recently injection-molded lead cladding tube can simply be pulled or pushed off its mold core in a straight line. In all of this, it should be noted that the correct dimensioning of the thread projections is crucial. The thread projections are usually designed with a flatter than usual flank angle, typically less than or equal to 45°. This reduces the force that the mold core can exert when pulling it out, before the lead cladding tube expands radially far enough and allows the mold core to slip out.In some cases, the thread projections are rounded or additionally rounded, preferably as the so-called round threads or sliding threads known to those skilled in the art.

[0022] It is also important to note that the thread projections should be sufficiently wide to be resilient and not tear or shear in the area of ​​the thread base. Typically, their width is at least a factor of two or even 2.5 times greater than the width of the thread groove or thread depression formed between two such thread projections. Thus, the thread projections of the mine casing tube are sufficiently shear-resistant.

[0023] Typically, the radially outermost end of the thread projections is not pointed, but flattened, forming a plane. This also benefits the shear strength right up to the tip area.

[0024] Further design options, modes of operation, and advantages are set out in the dependent claims, the exemplary embodiment, and the scaled-up drawings. LIST OF FIGURES

[0025] Fig.l shows a cartridge according to the invention in a central longitudinal section, which can be screwed to a main part of a cosmetic applicator via its coupling 11a, for example like the lower part of a ballpoint pen, or can be plugged onto such a part and locked into place.

[0026] Fig. 2 shows the cartridge 5 of Fig. 1 with the mine casing tube shown transparently.

[0027] Fig. 3 shows a central longitudinal section of the mine casing tube.

[0028] Fig. 4 shows the mine guide tube 21.

[0029] Fig. 5 shows the exact structure of the

[0030] Mine base consists of the inner and outer tube bodies 24, 25, which are only in contact via the web 26 and otherwise float away from each other.

[0031] FROM A LEADERSHIP EXAMPLE

[0032] The embodiment shown in Figures 1 to 5 embodies a cartridge for a refillable eyeliner, the main applicator part of which is not shown here.

[0033] It can be clearly seen from Figure 1 that the cartridge 1 has a lead casing tube 15 which here, for example, forms the outermost casing of the cartridge 1, i.e. provides the surface that the user grips with their hands when using the cartridge 1 or the corresponding eyeliner. A lead guide tube 21 is arranged in the casing tube 15 so as to be slidably rotatable, but fixed in the direction of the longitudinal axis 19 while avoiding any translational movement. The first sliding bearing G1 of the lead casing tube 15 is arranged in the area of ​​the lead tip behind the exit opening of the lead. The lead casing tube 15 forms an annular shoulder into which the front end of the lead guide tube 21 is pushed and is then held so as to be slidably rotatable. The second sliding bearing G2 of the lead casing tube forms the cylindrical section-like or...bell-shaped flexible apron 27, which here overlaps the coupling half 11a, which will be explained in more detail shortly, and is sealingly spread into a circular counter-bearing surface on the inner circumferential surface of the mine casing tube 15.

[0034] It can be clearly seen that the lead guide tube 21 has a longitudinal slot 22, preferably straight, along most of its length. The lead guide tube 21 is provided on its side facing away from the application tip with the coupling half 11a, which is usually attached to it in one piece.

[0035] The slotted lead guide tube 21 works together with a specially designed lead base 23. The lead base 23 essentially consists of two coaxially arranged, but predominantly radially spaced tubular bodies 24 and 25. The outer tubular body 25 has the shape of a cylindrical sleeve with an external thread and forms a threaded section. It is only connected to the actual lead holder, i.e. the inner tubular body 24, via a longitudinal web 26. In this way, a C-shaped free space exists between the actual lead holder and its threaded section, through which the slotted lead guide tube 21 passes when assembled. This can be seen in Figure 1 in

[0036] Compare with Figure 5.

[0037] Once you understand this, you will understand how the feed mechanism works.

[0038] Once the cartridge is mounted on the applicator main body, it can be imparted a rotational movement by the applicator main body via its coupling half on the way to its own coupling half 11a. This causes the lead guide tube 21 to rotate relative to the lead casing tube 15. In this way, the lead base 23 also rotates in its entirety, including the lead.

[0039] Since its outer surface engages with the internal thread forming the first threaded island Gil of the mine casing tube (Fig. 3), the mine base 23 screws forward, pushing the mine 16, which is anchored to it, forward. Before the outer thread of the mine base 23 completely disengages from the first threaded island Gil, it reaches the second threaded island Gi2 and immediately screws along it. The process is repeated with the other threaded islands, including Gi3, Gi4, Gi5, Gi6, and Gi7.

[0040] It can be clearly seen from Figures 2 and 3 that the thread islands, consisting of the thread projections 28, which run parallel to one another in a thread-like manner, are positioned such that they form at least three rows (then 3 x 120°), ideally four rows of at least three thread islands each, which form thread islands that are aligned one behind the other in the direction of the longitudinal axis 19 - preferably either completely or substantially.

[0041] 1 cartridge

[0042] 11a Coupling half

[0043] 15 mine casing tube

[0044] 16 mines

[0045] 19 Longitudinal axis

[0046] 21 Mine guide tube

[0047] 22 Longitudinal slot

[0048] 23 Lead base or lead holder

[0049] 24 inner tube body

[0050] 25 outer tube body

[0051] 26 Longitudinal web

[0052] 27 Sealing apron

[0053] 28 thread before jump

[0054] Gl first plain bearing

[0055] G2 second plain bearing

[0056] Gi l first to

[0057] Gi7 seventh thread island

[0058] Note: Non-listed reference numbers are not assigned

Claims

PATENT CLAIMS 1. Cosmetic applicator or assembly part, e.g. B. Cartridge (1) for a cosmetic applicator, with a threaded spindle drive for displacing a lead (16) consisting of cosmetic mass relative to a lead casing tube (15) accommodating the lead (16) (in whole or in part), wherein a thread is formed on the inner circumferential surface of the lead casing tube (15), which thread interacts with the complementary thread of a lead holder (23) holding the lead (16) directly or indirectly and translates the lead holder (23) together with the lead (16) relative to the lead casing tube (15) when one of the lead holders (23) is rotated relative to the lead casing tube (15), characterized in that said thread of the lead casing tube (15) is not a continuous thread, but consists of a number of thread islands (gil,...) spaced apart from one another (at least by more than one thread groove)., Gi7), each of which has thread projections extending by less than 121° in the circumferential direction and is designed and arranged such that the external thread of the lead holder (23) is always in engagement with at least one thread island.

2. Cosmetic applicator or component, e.g., cartridge (1), for a cosmetic applicator, according to claim 1, characterized in that the lead holder (23) with lead (16) slides in a lead guide tube (21) which is rotatably mounted in the lead casing tube (15) and is predominantly spaced apart from it, wherein the lead guide tube (21) is predominantly slotted and the lead holder (23) is guided over the slot (22) with its thread section forming a complementary thread.

3. Cosmetic applicator or component, e.g. cartridge (1), for a cosmetic applicator, according to claim 1 or 2, characterized in that the threaded section is a cylindrical sleeve which is closed in the circumferential direction and which is connected to the actual lead holder (23) only via a longitudinal web (26), so that between the actual lead holder (23) and its threaded section there is a C-shaped free space through which the slotted lead guide tube (21) extends.

4. Cosmetic applicator or component, e.g., cartridge (1), for a cosmetic applicator, according to one of the preceding claims, characterized in that the lead guide tube (21) forms a coupling half (11a) on one end face, which can be connected to another coupling half of the or an applicator main part in order to receive a feed-inducing rotary movement transmitted therethrough.

5. Cosmetic applicator or component, e.g. cartridge (1), for a cosmetic applicator, according to one of the preceding claims, characterized in that the lead guide tube (21) is rotatably mounted on the lead casing tube (15) at two spaced-apart bearing points, namely in the region of a coupling half (11a) and in the region of the preferably tapered tip with the outlet opening of the lead casing tube (15) for the lead (16), which in the region behind the outlet opening on its inner circumferential surface a corresponding plain bearing shoulder for the mine guide tube (21).

6. Cosmetic applicator or component, e.g. cartridge (1), for a cosmetic applicator, according to one of the preceding claims, characterized in that the mounting in the region of a coupling half (11a) is carried out by means of a cylinder-section-like flexible apron (27), which preferably extends partially over the coupling half (11a) and which is in each In this case, it is sealingly spread into a circular counter-bearing surface on the inner circumferential surface of the mine casing tube (15).

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