A disc arrangement for an epilator

EP4637473B8Active Publication Date: 2026-06-03KONINKLIJKE PHILIPS NV

Patent Information

Authority / Receiving Office
EP · EP
Patent Type
Patents
Current Assignee / Owner
KONINKLIJKE PHILIPS NV
Filing Date
2023-12-11
Publication Date
2026-06-03

AI Technical Summary

Technical Problem

Existing epilating devices with rotating tweezer mechanisms struggle to achieve an optimal gripping force on hairs while maintaining a low cost design, leading to potential hair breakage and high sound output.

Method used

A hybrid disc arrangement for epilators using alternating metal and plastic peripheral gripping regions on adjacent discs, where metal regions are textured for enhanced grip and plastic regions provide a softer interface, manufactured through overmolding.

Benefits of technology

Improves tweezer grip on hairs, reduces hair breakage, and lowers sound output compared to all-plastic or all-metal designs, while being suitable for industrial production.

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Description

FIELD OF THE INVENTION

[0001] The present invention relates to epilating devices and in particular to the tweezer portion of the epilator.BACKGROUND OF THE INVENTION

[0002] Epilating devices of many different types are known for the purpose of removing unwanted hair from various regions of a user's body. The principles of operation vary greatly but amongst these devices, a sizeable subgroup operates through the use of rotating tweezer mechanisms which seize hairs and actively extract them from the skin follicle. As the tweezer rotates further it releases the hair. In the present context, the term "tweezers" is used to denote an arrangement that is capable of opening and closing to grip and extract a hair or hairs.

[0003] One of the earliest devices of this type is the Epilady ™< device, which uses the rotation of a coil spring to capture and release hairs. Another type of device is disclosed in EP532106B1 which uses rotating disks which are pivotable towards each other under the influence of a compression member.

[0004] This invention relates to epilating devices which use a series of adjacent discs to implement a set of tweezers. The effectiveness of the operation of the tweezer type epilator depends in part on the gripping force applied to the hairs by the tweezers, in use. The gripping force depends on the friction and hence the design of the portions which form the tweezers. There is a desire to improve the gripping force while enabling a low cost design.

[0005] EP 3 915 430 A1 discloses a head unit of a depilation appliance comprising at least one pair of hair-clamping elements which have tweezer surfaces arranged to face each other. The tweezer surfaces are movable towards and away from each other, i.e., into and out of contact with each other. In order to achieve improved hair-clamping performance of the pair of hair-clamping elements, the tweezer surfaces are configured to align relative to each other when they move into contact with each other. In an embodiment, one of the hair-clamping elements of the pair is adjustable in that its tweezer surface is arranged so as to be movable in the respective hair-clamping element by being included in a tilting element made of metal. In this embodiment, the rest of the adjustable hair-clamping element of the pair may be made of plastic, and the other hair-clamping element of the pair may be entirely made of plastic.SUMMARY OF THE INVENTION

[0006] The invention is defined by the claims.

[0007] According to an aspect of the invention, there is provided a disc arrangement for an epilator, comprising a set of epilator discs, wherein each disc has peripheral hair gripping portions, wherein adjacent discs are for performing a tweezer hair removal function between them at a set of hair removal locations, wherein at each hair removal location, there is: a first portion of a first disc which is metal; and a second portion of a second disc which is plastic; wherein the disc arrangement comprises a set of central discs arranged between two end discs, and wherein each central disc comprises first peripheral hair gripping regions which are metal and second peripheral hair gripping regions which are plastic.

[0008] In order to increase tweezer grip on the hair, the surface roughness of the tweezers should be increased. Measurements indicate that in order to do this effectively, a hard material such as metal provides the best hair grip results.

[0009] The disc arrangement of the invention may be considered to be a hybrid design, with different materials (plastic and metal) facing each other to define each tweezer. This provides an improvement to existing disc epilator systems by increasing the grip of the tweezers on the hairs needed for extraction from the skin.

[0010] By combining metal and plastic surfaces to perform the gripping function, the performance may be improved compared to an all-plastic design, and the design may also be more suitable for industrialization compared to an all metal design.

[0011] The use of metal and plastic surfaces also gives a lower sound output and also a lower risk of hair breakage compared to a design with metal at both sides.

[0012] Because each central disc comprises first peripheral hair gripping regions which are metal and second peripheral hair gripping regions which are plastic, metal-plastic tweezers may be formed using a single central disc design, by mating the plastic parts of one disc with the metal parts of an adjacent disc.

[0013] Of course, there may be different disc designs of the end discs of the disc arrangement, so the identical disc design may be used for at least the cenral discs between the end discs.

[0014] The first peripheral hair gripping regions for example face one side of the central disc and the second peripheral hair gripping regions face an opposite side of the central disc. The first and second peripheral hair gripping regions are for example alternated around the central disc. In one example, there are four tweezer positions for each central disc spaced at 90 degrees. There are then two tweezers formed with the adjacent disc on one side and two tweezers formed with the adjacent disc on the other side.

[0015] The first peripheral hair gripping regions may have a textured surface. The metal portion thus has a textured surface, for example formed by laser etching. This improves grip.

[0016] Each central disc may comprise a metal base which defines the first hair gripping regions and an overmolded plastic portion which defines the second hair gripping regions. This enables easy manufacture, with a metal base which is large enough to enable simple overmolding and a sufficient amount of plastic for the overmolding process.

[0017] The overmolded plastic portion for example comprises embedded particles or fibers which are harder than the metal of the metal base.

[0018] The particles or fibers roughen their metal counterpart over time to obtain optimized grip on the hairs and maintain proper surface roughness over the lifetime of the epilator. The embedded particles or fibers for example comprise glass particles or fibers.

[0019] The invention also provides an epilator comprising: a housing; a motor located in the housing; and the disc arrangement as defined above.

[0020] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.BRIEF DESCRIPTION OF THE DRAWINGS

[0021] For a better understanding of the invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which: Fig. 1 shows a front view of a known epilating device to which the invention may be applied; Fig. 2 shows a known disc design; Fig. 3 shows a disc assembly; Fig. 4 shows a disc design in accordance with the invention; Fig. 5 shows the metal base part of the design of Fig. 4; and Fig. 6 shows the overmolded plastic part of the design of Fig. 4. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The invention will be described with reference to the Figures.

[0023] It should be understood that the detailed description and specific examples, while indicating exemplary embodiments of the apparatus, systems and methods, are intended for purposes of illustration only and are not intended to limit the scope of the invention. These and other features, aspects, and advantages of the apparatus, systems and methods of the present invention will become better understood from the following description, appended claims, and accompanying drawings. It should be understood that the Figures are merely schematic and are not drawn to scale. It should also be understood that the same reference numerals are used throughout the Figures to indicate the same or similar parts.

[0024] The invention provides a disc arrangement for an epilator, comprising a set of epilator discs. Each disc has peripheral hair gripping portions, wherein adjacent discs are for performing a tweezer hair removal function between them at a set of hair removal locations. At each hair removal location, there is a first portion of a first disc which is metal and second portion of a second disc which is plastic.

[0025] Fig. 1 shows a known epilating device 1 to which the invention may be applied.

[0026] The epilating device comprises an epilation opening in which a disc assembly 16 is mounted. The disc assembly comprises central discs 12 and end discs 10, 14 which are rotated via a drive 2 provided within the epilating device.

[0027] Fig. 2 shows an example of a known design for the central discs 12. It has a substantially circular shape. Circumferential regions 18, 20 of the disc 12 are made from a relatively hard material, for example a glass-filled plastic with at least 40% glass fibers. These circumferential regions function as gripping regions. The other regions are made from a softer material having good gliding properties such as a PTFE-filled plastic. The combination of hard and soft materials means the contact surfaces of the tweezers can be prevented from unacceptable wear.

[0028] The gripping regions 18, 20 form part of a clamping portion intended to interact with further clamping portions of a neighboring disc, as is well known to the person skilled in the art. Each gripping region may be considered to comprise a tweezer, while two abutting gripping regions form a tweezer pair. Each tweezer is raidally beyond a channel 19 which helps to define the exact gripping area. The gripping area is at a slight angle compared to the area behind the channel. The design of the channel prevents a sharp edge being present that could cause unwanted strain on the hair (and hence hair breakage).

[0029] The two diametrically opposed gripping regions 18 are for forming tweezers with an adjacent disc to one side of the disc and the two diametrically opposed gripping regions 20 are for forming tweezers with an adjacent disc to the opposite side of the disc.

[0030] The disc 12 comprises torque transmitting means 22 for transmitting a torque from / to a neighboring disc in the disc assembly 16. The torque transmitting means are formed by projections 22 on one side and recesses on the opposite side, wherein the projections are configured such that they can engage in the recesses of a neighboring disc to receive / transmit the torque.

[0031] The known disc 12 is made by a 2K molding process, to enable the disc to be formed with the relatively hard and relatively soft portions as mentioned above. A more detailed discussion of an example of this type of disc may be found in US 8 608 756.

[0032] It is also known to form the disc fully as a uniform glass-filled plastic body.

[0033] Fig. 3 shows a sectional view of the known disc assembly 16. This example shows nine central discs 12 arranged between two end discs 10 and 14. The end disc 14 comprises side bearing means 36 which are intended to interact with bearing means of the epilating epilating device (not shown). The end disc 10 comprises torque transmitting means 32 which are intended to receive a torque created by the drive of the epilating device. Center bores of the discs 10, 12, 14 have a diameter which is slightly larger than a diameter of a shaft 50 on which the discs are arranged. This is necessary to enable the necessary pivot motion when the epilating apparatus is in operation.

[0034] Fig. 4 shows an example of the disc design of the central discs 12 in accordance with the invention. It may be applied to the epilator of the general type shown in Figs. 1 and 3.

[0035] As with the known disc design, the central disc 12 has circumferential gripping regions 18 facing one side and circumferential gripping regions 20 facing the other side. When the disc is adjacent identical other discs (but with a 90 degree offset) two tweezers are formed at one side and two tweezers are formed at the other side.

[0036] The disc may however have more or fewer gripping regions, and the choice of four gripping regions (two facing each way) is simply an example.

[0037] As the discs rotate, the gripping regions present a narrowing channel over entrapped hairs and thereby pull them out.

[0038] This invention provides an improvement to the disc design, which increases the grip of the tweezers on the hairs needed for extraction form the skin. In particular, in order to increase tweezer grip on the hair, a hard material should be used, and preferably also the surface roughness of the tweezers should be maintained as large as possible.

[0039] The disc of Fig. 4 is formed of metal parts and plastic parts. The metal parts define one of the pairs of gripping regions, e.g. gripping regions 18, and the plastic parts define the other of the pairs of gripping regions, e.g. gripping regions 20.

[0040] The disc is formed by an overmolding process, such that plastic is overmolded over a metal base. The interface between the metal part 60 and the plastic part 62 is for example represented by line 64 in Fig. 4. The metal base is thus an insert into the plastic mold.

[0041] The combination of metal and plastic gripping regions in each individual disc enables a single design for the central discs 12. Because the base and the overmolding each create half (in this example two) of the peripheral gripping regions, there is a suitable base for the overmolding as well as sufficient added volume of the plastic overmolding. This is only one option, and the metal part may instead be connected in a different (mechanical) way.

[0042] When one central disc 12 is adjacent an identical central disc 12 (with a 90 degree offset) each tweezer is formed by the interface between a plastic gripping region and a metal gripping region. Thus, the two surfaces that face each other to form a tweezer have different materials.

[0043] Fig. 5 shows the metal base part 60, which defines the first pair of gripping regions 18.

[0044] Fig. 6 shows the shape of the plastic overmolding 62. This does not exist as a separate component because it is formed over and around the metal base part 60. It is shown simply for clarity. It defines the second pair of gripping regions 20.

[0045] The metal base 60 is for example textured after the overmolding process, for example by laser etching. This texture gives an increased surface roughness, for example with greater roughness than the facing plastic part of the adjacent disc. The metal gripping region may also be provided with a low friction rim (plastic and / or a coating) in order to protect the skin from getting into direct contact with the metal tweezer part.

[0046] The plastic part 62 for example comprises a plastic body filled with particles or fibers which are harder than the metal. For example, glass particles are used to roughen their metal counterpart over time to obtain optimized grip on the hairs and maintain proper surface roughness over the product's lifetime. Thus, it has been found that embedded particles such as glass fibers can be very abrasive to their metal counterpart, automatically roughening the metal surface over time. The particles or fibers also give the plastic discs more stiffness and make them less prone to plastic deformation and relaxation over time (as is already known).

[0047] The particles or fibers may be glass beads or fibers, or carbon fibers or chalk particles. Instead of embedded particles of fibers, a coating may be applied to the plastic part.

[0048] The embedded particles are for example mixed with the plastic before the molding process. By way of example the plastic may comprise PA66+60%GF, i.e. polyamide (nylon) with 60% glass fibers.

[0049] The invention may be applied to any epilator device which uses adjacent rotating discs to perform a tweezer function.

[0050] Variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention as disclosed in the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.

[0051] If the term "adapted to" is used in the claims or description, it is noted the term "adapted to" is intended to be equivalent to the term "configured to". If the term "arrangement" is used in the claims or description, it is noted the term "arrangement" is intended to be equivalent to the term "system", and vice versa.

[0052] Any reference signs in the claims should not be construed as limiting the scope.

Claims

1. A disc arrangement (16) for an epilator (1), comprising a set of epilator discs (10, 12, 14), wherein each disc has peripheral hair gripping portions, wherein adjacent discs are for performing a tweezer hair removal function between them at a set of hair removal locations, wherein at each hair removal location, there is: a first portion (18) of a first disc which is metal; and a second portion (20) of a second disc which is plastic; characterized in that the disc arrangement (16) comprises a set of central discs (12) arranged between two end discs (10, 14), wherein each central disc comprises first peripheral hair gripping regions (18) which are metal and second peripheral hair gripping regions (20) which are plastic.

2. The disc arrangement (16) of claim 1, wherein the first peripheral hair gripping regions (18) face one side of the central disc (12) and the second peripheral hair gripping regions (20) face an opposite side of the central disc.

3. The disc arrangement (16) of claim 1 or 2, wherein the first peripheral hair gripping regions (18) have a textured surface.

4. The disc arrangement (16) of any one of claims 1 to 3, wherein each central disc (12) comprises a metal base (60) which defines the first hair gripping regions (18) and an overmolded plastic portion (62) which defines the second hair gripping regions (20).

5. The disc arrangement (16) of claim 4, wherein the overmolded plastic portion (62) comprises embedded particles or fibers which are harder than the metal of the metal base (60).

6. The disc arrangement (16) of claim 5, wherein the embedded particles or fibers comprise glass particles or fibers.

7. An epilator (1) comprising: a housing; a motor located in the housing; and the disc arrangement (16) of any one of claims 1 to 6.