Blade set for a hair clipper

Abstract

The invention relates to a blade set for a hair clipper (10), which has a base body (12) and a blade set (14) rigidly connected thereto, wherein the blade set (14) comprises a stationary blade (16) and a moving blade (18), the moving blade (18) having a base section (20) with a tooth end (22) having a plurality of mutually parallel teeth (24), the teeth (24) extending outwards in the longitudinal direction of the hair clipper (10) in a cutting area (28) of the blade set (14) with their tooth tips (26). The blade set according to the invention is characterized in that the teeth (24) of the moving blade (18) are dimensioned such that their width (B) in the area of ​​the respective tooth tip (26) is significantly smaller than the distance (A) between any two adjacent teeth (24).

Description

[0001] The invention relates to a blade set for a hair clipper as defined in claim 7 and a blade as defined in claim 1.

[0002] Electric hair clippers have been around for a long time and include, among other things, a set of blades located at a front end of the hair clipper's housing and suitable for cutting hair.

[0003] The blade set of a hair clipper generally consists of two blades: a stationary blade, called the comb, which comes into contact with the skin of the person or animal being treated, or the user, and a moving blade, also called the cutter. Each blade has a row of spaced-apart teeth, with the teeth usually arranged at regular intervals.

[0004] Both blades of a blade set typically have a toothed edge that corresponds to the hair or skin of the person or animal being treated. The two blades of the blade set are arranged so that the respective toothed edges overlap each other. During operation, the movable blade moves back and forth relative to the fixed or stationary blade to perform the cutting action. During this back-and-forth movement, the toothed edge of the movable blade interacts with the teeth of the fixed blade to enable the cutting of hair caught between the individual teeth in a scissoring motion.

[0005] Thus, the strands of hair that enter between the teeth of the fixed blade are cut as the teeth of the moving blade move back and forth across the teeth of the fixed blade.

[0006] The moving blade is also referred to as the shearing blade or simply as the "blade." The fixed blade is also referred to as the shearing comb or simply as the "comb."

[0007] The hair is cut when the cutting elements, i.e. the teeth, of the shearing blade are moved over the corresponding blade pieces of the stationary shearing comb.

[0008] This cutting motion cuts the hair that is in the area between the teeth.

[0009] A distinction is usually made between two types of hair cutting: cutting hair at a certain distance from the skin of the person or animal being treated and cutting and removing hair close to the skin.

[0010] Both types of hair cutting require that the cutting be carried out with sufficient cutting power, ie both quickly and thoroughly, ie all hair in the area covered by the hair clipper should be removed in one operation and as smoothly as possible, so that precise work is possible and the cutting is comfortable for the person being treated.

[0011] Cutting close to the skin also requires the additional requirement of avoiding skin injuries in humans and animals. Such injuries are likely to occur if the distance between the comb tip and the blade tip is minimal, so that both tips almost overlap. However, a minimal distance between the comb tip and the blade tip is required for cutting longer hair close to the skin with trimmers or hair clippers. Electric razors, which are based on a different cutting concept, also cut close to the skin, but are not suitable for cutting longer hair; they are suitable only for cutting very short hair or stubble.

[0012] In order to avoid injuries to the skin, according to the current state of the art, the cutting edge of the movable blade is set back compared to the fixed blade, namely the blade facing the skin, so that the fixed blade serves as a spacer or spacer guard to prevent skin from penetrating the cutting area and cutting the skin of the person being treated.

[0013] However, these spacers mean that with the cutting blades known in the state of the art, i.e. the movable blades, for use in cutting close to the skin, only an insufficient trimming of the treated hair area can be achieved without there being a risk of skin irritation or injury.

[0014] EP 3 769 920 A1 discloses a trimmer blade comprising a stationary blade including a plurality of first blades and a movable blade including a plurality of second blades and sliding relative to the stationary blade, wherein a front end of one of the plurality of first blades includes a projection projecting from a first sliding surface of the one of the plurality of first blades, and a front end surface of one of the plurality of second blades contacts the projection.

[0015] The object of the present invention is therefore to provide a blade set for an electric hair clipper and a moving blade of a blade set which has an improved cutting performance for cutting hair close to the skin, while at the same time ensuring that no skin injuries are caused.

[0016] This object is achieved by a blade for a blade set for a hair clipper having the features of claim 1.

[0017] Preferred embodiments and further developments of the blade according to the invention and of the blade according to the invention emerge from the dependent claims.

[0018] In order to achieve the above-mentioned object, a blade set for a hair clipper is provided according to the invention, which is characterized by a special geometry of the cutting blade of the blade set.

[0019] The blade set according to the invention for a hair clipper, which has a base body and the blade set connected thereto, comprises, in a conventional manner, a fixed blade and a moving blade. The moving blade has a base section with a toothed end with a plurality of parallel teeth, wherein the teeth extend outward with their tooth tips in the longitudinal direction of the hair clipper in a cutting area of ​​the blade set.The blade set according to the invention is characterized in that the teeth of the moving blade are dimensioned such that their width B in the region of the respective tooth tip is substantially smaller than a distance between two adjacently arranged teeth in such a way that the distance A between the adjacent teeth of the moving blade is approximately at least three times as large or more than the width B of the tooth tips of the teeth of the moving blade, wherein the width (B) of the tooth tips (26) of the teeth (24) is substantially in the range of less than 0.24 mm.

[0020] The rate at which hair is fed into the cutting area of ​​the blade set is significantly influenced by the width of the tooth tips. It should be noted that the feed rate corresponds to the proportion of hair that penetrates the cutting area relative to the hair that is prevented from penetrating due to obstacles placed in the penetration area and thus not cut. Due to the very narrow teeth of the moving blade, which are designed according to the invention, more hair can penetrate between the shearing comb teeth and advance unhindered into the cutting area, allowing a significantly higher number of hairs to be cut with a single cutting motion.

[0021] The invention provides that the distance A between the adjacent teeth of the moving blade is preferably at least three times as large as or more than the width B of the tooth tips of the teeth of the moving blade. In even more preferred embodiments of the present invention, the ratio A:B is in a range from 3 to 20. For example, in the case of a ratio A:B of 20 and a tooth tip width B of 0.1 mm, the distance A between the teeth is 2 mm. Thus, the particularly narrow design of the teeth ensures that the distance between the individual teeth is effectively used in the cutting process by allowing a greater number of hairs to be cut with one cutting movement without significantly increasing the dimensions of the cutting area and thus of the entire hair clipper in the width direction.

[0022] The width B of the tooth tips of the teeth of the moving blade is substantially in the range of less than 0.24 mm, and in particular in a range between 0.10 mm and 0.24 mm, and particularly preferably in the range of 0.13-0.19 mm. In further specific embodiments of the present invention, the width B of the tooth tips is 0.14 and 0.18 mm.

[0023] The width range of 0.13 to 0.19 mm for the tooth tips of the moving blade's teeth represents an optimum, since the highest feed rate could theoretically be achieved with infinitesimally narrow tooth tips. Such narrow tooth tips ensure that the mechanical load capacity is adequately maintained. It should be noted that the tooth tips of the moving blade's teeth known from the prior art have a width in the range of 0.28 mm.

[0024] The width B of the tooth tips of the moving blade's teeth is not necessarily measured at the edge, i.e., the leading edge, of the tooth tips. It can also be measured slightly below the leading edge in the case of tooth tips that do not have a linear contour but are wavy and / or curved.

[0025] Although the linear leading edge is considered to provide the best performance, other leading edge shapes also represent further preferred embodiments of the present invention.

[0026] Preferably, each individual tooth tapers towards the end of the tooth and, in particular, takes the form of a regular or irregular truncated pyramid, allowing for very narrow teeth without compromising their stability during hair cutting and thus their cutting effect. The term "truncated pyramid" refers to a geometric shape created by cutting a smaller, similar pyramid (a so-called "supplementary pyramid") from an original pyramid, parallel to the base surfaces, along the outer surfaces. The two parallel surfaces of a truncated pyramid are similar to each other. The larger of these two surfaces is called the base surface, the smaller the top surface. The distance between the base and top surfaces is called the height of the truncated pyramid.

[0027] The volume of a truncated pyramid can be calculated using the following formula: V = h 3 A 1 + A 1 ∗ A 2 + A 2

[0028] The focus is A 1 for the floor area, A 2 for the top surface and h for the height of the truncated pyramid.

[0029] There is no simple formula for the surface area composed of trapezoids. The more skewed the pyramid, or truncated pyramid, is, the larger its corresponding surface area. If the base to top surface approaches a circle, the geometric "extreme" is a truncated cone. If A 2 approaches A 1, the further geometric "extreme" is a prism, whose volume formula is simplified accordingly by A 1 = A 2 = A. If A 2 approaches 0, the result is a pyramid.

[0030] In this case, the shape of the truncated pyramid lies in the area between the two geometric extremes of a truncated cone and a prism.

[0031] The ratio between the width B of the tooth tips of the teeth of the moving blade and the width B' of a tooth base is preferably in a range of 1:1.25 to 1:3, and in a preferred embodiment is 1:2, and in still further preferred embodiments of the invention, 1:1.5 and 1:2.5. The upper value of the range, i.e., a ratio of 1:3, also leads to the effect according to the invention. This results in a particularly stable and effective formation of the individual teeth.

[0032] It is particularly preferred if the tooth tips of the teeth of the moving blade are designed such that they extend substantially perpendicular to the longitudinal axis of the hair clipper.

[0033] A further particularly advantageous embodiment of the invention provides that the tooth tips of the teeth of the moving blade are substantially flat and extend in the width direction substantially perpendicular to a surface which serves as a cutting edge and extends downwards in the longitudinal direction of the respective tooth, wherein an opposite end of the respective tooth tip is rounded.

[0034] A rounded edge on the top of the tooth of the moving blade, in the most preferred embodiment of 90° + / - 4°, ensures that no knife edge is created that could cut into the skin of the person being treated like a kitchen knife due to the back-and-forth movement of the moving blade or shearing blade. In further preferred embodiments, the angle is in a range of 81° to 98°, more preferably 83° to 96°, for example, at a value of 85° or 95°.

[0035] This tooth tip geometry with the almost right-angled design of the moving blade in the area of ​​the tooth tips is particularly advantageous when cutting perpendicular to the skin surface in order to avoid damage to the skin of the person being treated.

[0036] The flat and wide tooth tip also offers improved cutting performance when cutting parallel to the skin surface, as the hair to be cut is grasped by the wide flank of the teeth over a longer section of hair and guided into the cutting area without being able to "slip away" from the cutting area over the front edge of the teeth, as disadvantageously happens with a tapered tooth tip. With a tapered tooth tip, as is known from the prior art, the hair bends slightly over the bevel of the tip and is accelerated by the back-and-forth movement of the blade, resulting in a forward force that actively pushes the hair lying above the bevel away from the cutting area, like a downhill force.

[0037] The area adjacent to the cutting edge is designed at an angle of 90°, preferably in a range of 81° to 98° as explained in more detail above, ie this effect can even be achieved by an angle slightly smaller or slightly larger than 90°.

[0038] Preferably, the tooth tips have a leading edge which is substantially linear, wherein their end sections extend substantially perpendicular to the leading edge or are partially and / or completely rounded.

[0039] Although the linear design of the leading edges is considered to be particularly preferred, the tooth tips can also have a rounded leading edge and / or a wavy leading edge, whereby the advantageous properties of the moving blade are not impaired.

[0040] The object of the invention is further achieved by a blade for a blade set for a hair clipper. The blade is a moving blade having a base section and a toothed end, wherein the blade has a plurality of teeth arranged parallel to one another, which extend outward with their tooth tips in a cutting region of the blade set in the longitudinal direction of the hair clipper. The blade according to the invention is characterized in that the teeth of the moving blade are dimensioned such that their width B in the region of the respective tooth tip is significantly smaller than a distance A between any two adjacent teeth.

[0041] Preferably, the width B of the tooth tips of the teeth is substantially in the range of less than 0.24 mm, preferably in a range between 0.10 mm and 0.24 mm, and more preferably in the range of approximately 0.13-0.19 mm. In further specific embodiments of the present invention, the width B of the tooth tips is between 0.14 and 0.18 mm.

[0042] As already explained above, the width range of 0.13 to 0.19 mm of the tooth tips of the teeth of the moving blade represents an optimum, since the highest feed rate could theoretically be achieved by infinitesimally narrow tooth tips.

[0043] Particularly preferably, the tooth tips of the teeth of the blade according to the invention are substantially flat and extend in the width direction substantially perpendicular to a surface which serves as a cutting edge and extends downwards in the longitudinal direction of the respective tooth, wherein an opposite end of the respective tooth tip is preferably rounded.

[0044] Preferably, the tooth tips of the blade according to the invention have an edge which is substantially linear, wherein their end sections run substantially perpendicular to the edge or are partially and / or completely rounded, and wherein an area adjacent to the cutting edge, which corresponds to a firmly connected blade, branches off at an angle in a range of 81 to 98°, very particularly preferably 90°, as already explained in more detail above, to which explicit reference is also made here.

[0045] However, the blade according to the invention can also be designed in such a way that the tooth tips have a rounded edge and / or a wavy edge.

[0046] According to the invention, a hair clipper is also provided with a housing body and a blade set according to the invention connected thereto.

[0047] Advantageous further developments and embodiments emerge from the subclaims and from the following exemplary embodiments, as shown in more detail in the drawings.

[0048] They show: Fig. 1 is a partial perspective view of a hair clipper according to the invention with the blade set according to the invention according to an embodiment of the present invention; Fig. 2 is a plan view of a moving blade according to the prior art; Fig. 3 is a plan view of a moving blade according to an embodiment of the present invention; Fig. 4 is an enlarged partial view of a moving blade in the area of ​​the teeth according to Fig. 3 ; Fig. 5 a side view of a moving blade according to Fig. 3 ; Fig. 6 an enlarged partial side view in the area of ​​a tooth of the moving blade according to Fig. 5 ; Fig. 7 is an enlarged partial side view in the region of a tooth of the moving blade according to the prior art; Fig. 8 is an enlarged partial side view in the region of a tooth of the moving blade, as in Fig. 6Fig. 9 is a schematic side view of a hair clipper according to the invention with a built-in blade set according to the invention; Fig. 9a is an enlarged view of the blade set according to Fig. 9 in the area of ​​the tooth tips.

[0049] In Figure 1 A partial perspective view of a hair clipper 10 according to the invention with the blade set 14 according to an embodiment of the present invention is shown. The hair clipper 10 has a base body 12 to which the blade set 14 is connected.

[0050] The blade set 14 comprises a fixed blade 16 and a moving blade 18 which are connected to each other, wherein, as can be seen from Fig. 1As can be seen, the moving blade 18 is arranged on the fixed blade 16 below. The fixed blade 16 is in contact with the skin of the person or user being treated and is also referred to as a so-called shaving comb or simply a comb.

[0051] Both the stationary blade 16 and the moving blade 18 have a toothed edge and are arranged one above the other so that the respective tooth edges overlap. During operation, the two blades 16 and 18 move back and forth relative to each other to enable a cutting action.

[0052] Both the fixed blade 16 and the moving blade 18 of the Fig. 1 illustrated blade set 14, have a base section not shown here, via which the two blades are connected to each other and also to the main body of the hair clipper.

[0053] In Fig. 3The moving blade 18 is shown in plan view. The blade 18 has a base portion 20, which includes a tooth end 22 with a plurality of teeth 24 arranged parallel to one another. The teeth 24 extend outward with their tooth tips 26 in the longitudinal direction of the hair clipper in a cutting area of ​​the blade set.

[0054] The teeth 24 of the moving blade 18 are, as in Fig. 3 As shown, the teeth are dimensioned such that their width B in the region of the respective tooth tip 26 is significantly smaller than the distance A between two adjacent teeth 24. The width B is in the range of less than 0.24 mm. The width can certainly be in a range between 0.10 mm and 0.24 mm. A width of 0.18 mm or even 0.16 mm is considered a particularly preferred embodiment.

[0055] Fig. 4shows an enlarged partial view of the moving blade 18 in the area of ​​the teeth 24 according to Fig. 3 From this enlarged view, it is clear that the width B is significantly smaller than the distance A between any two adjacent teeth 24. The downward arrow indicates that the hair to be cut reaches the intermediate area between two adjacent teeth 24.

[0056] Due to the significantly larger distance A compared to the width B of the tooth tip 26, it is possible to increase the feed rate, ie the proportion of hair that penetrates into the cutting area. The penetrated hairs are in Fig. 4 shown schematically as points above the arrow.

[0057] Again Fig. 4As can be seen, the ratio between the width B of the tooth tips 26 of the teeth 24 of the moving blade 18 and the width B' of a tooth base 32 is approximately 1:2. However, this ratio can also be 1:3. The tooth can extend in a wedge shape toward the tooth tip 26.

[0058] In Fig. 2 a moving blade 38, or shearing knife, is shown according to the prior art, from which it can be seen that the width C in the area of ​​a tooth tip 40 is substantially larger than the width B in the area of ​​the tooth tip of the teeth of the moving blade according to Fig. 3 The width C, as in Fig. 2 shown, according to the current state of the art, is usually about 0.28mm.

[0059] In Fig. 5 is a side view of a moving blade 18 as shown in Fig. 3shown. In this figure, the geometry of the moving blade 18 is clearly visible, wherein in the area of ​​the teeth 24 it is clearly visible that the tooth tip 26 is flattened.

[0060] Out of Fig. 6 which is an enlarged partial side view in the area of ​​a tooth 24 of the moving blade 18 according to Fig. 5 As shown, it can be seen that the tooth tip 26 has a flat edge 28. The tooth 24 has a cutting edge 34, which corresponds to the underlying, fixed blade set (not shown here) and serves as a running surface that slides against the underlying tooth. The edge 28 at the tooth tip 26 represents a surface that can come into contact with the skin of the person being treated. The tooth tip has a rounded end 36.

[0061] In this embodiment, the edge 28 runs according to Fig. 6perpendicular to the cutting edge 34, wherein the two edges meet at a first end portion 30, and wherein a second end portion 30' is rounded at an opposite end of the edge 28.

[0062] This training according to Fig. 6 is for better illustration in Fig. 8 shown enlarged. The end section 30 has a straight part 43, designated F, which extends to the beginning of the rounding of the rounded end section 30'. The height 47 of the cutting tooth is designated H. Within the scope of the present invention, the ratio of F to H is in a range from 0.6 to 0.95, preferably 0.65 to 0.8. Particularly preferred values ​​are 0.7, 0.75, and 0.8.

[0063] The 90° design plus the radius (or "round edge") on the top of the moving blade 18 ensures that no knife edge is created that can cut into the skin due to the back and forth movement of the moving blade 18.

[0064] This tooth tip geometry is particularly advantageous when cutting perpendicular to the skin surface to avoid damage to the skin of the person being treated, as is the case in the Figures 9 and 9a shown. In Fig. 9a , which is an enlarged view of the blade set 14 according to the invention with the fixed blade 16 and the moving blade 18, from which the cutting perpendicular to the skin surface and the orientation of the blade set 14 can be seen. In the, in Fig. 9In the embodiment of the hair clipper 10 according to the invention shown, the blade set 14 is attached to a blade set carrier 42 and can be inserted and secured in a receptacle provided for this purpose in the base body 12 of the hair clipper 10. However, it is also possible for the blade set 14 to be detachably connected to the base body 12 of the hair clipper 10 by means of fastening means, such as screws.

[0065] Not only when cutting perpendicular to the skin surface, but also parallel to the skin surface, the flat and wide tooth tip offers improved cutting performance, as the hair to be cut is grasped by the wide flank of the teeth over a longer hair section and guided into the cutting area, without being able to "slip away" from the cutting area over the front edge of the teeth, as is the case with a pointed tooth tip 40 as is known from the prior art and in Fig. 7With such a pointed tooth tip, as shown in Fig. 7 As shown, the hair to be cut bends over the bevel of the tip and is accelerated by the back and forth movement of the blade, resulting in a forward-directed force that actively pushes the hair 44 lying above the bevel away from the cutting area, like a slope driving force. The hair 44 is aligned with the wavy line in the Figures 7 and 8 shown.

[0066] The area adjacent to the cutting edge can be designed at 90° or in an angle range of 81° to 98° - as explained in more detail above - ie this effect can even be achieved by an angle slightly smaller or slightly larger than 90°.

[0067] The scope of the present invention is defined by the appended claims. List of reference symbols

[0068] 10Hair clipper 12Main body 14Blade set 16Fixed blade 18Moving blade 20Base section 22Tooth end 24Tooth 26Tooth tip 28Flat edge 30First end section of edge 28 30Second end section of edge 28 32Tooth base 34Cutting edge 36Rounded end of tooth tip 38Moving blade (according to the state of the art) 40Tooth tip (according to the state of the art) 42Blade set carrier 44Hair 47Height of cutting tooth

Claims

1. Blade for a blade set (14) for a hair clipper (10), wherein the blade (18) is a movable blade (18) and has a base portion (20) and a tooth end (22), wherein the blade (18) has a plurality of teeth formed parallel to each other (24), which extend outwards, characterized in that the teeth (24) of the movable blade (18) are dimensioned such, that its width (B) in the region of the respective tooth tip (26) is substantially smaller than a distance (A) between two adjacent teeth (24) such that the distance A between the adjacent teeth of the movable blade (18) is at least three times as large or more than the width B of the tooth tips of the teeth of the movable blade (18) and the width (B) of the tooth tips (26) of the teeth (24) is substantially in the range of less than 0.24 mm.

2. Blade according to claim 1, characterized in that the width (B) of the tooth tips (26) of the teeth (24) is in a range between 0.10 mm and 0.24 mm.

3. Blade according to one of the preceding claims, characterized in that the edge (28) of the tooth tip (26) has a straight part (43, F) and a rounded end portion (30'), wherein the straight part (43, F) extends to the beginning of the rounding of the rounded end portion (30') and wherein the ratio of the lengths of the straight part F (43) to the height (47) H of the cutting tooth is in a range from 0.6 to 0.95, preferably 0.65 to 0.8.

4. Blade according to one of the preceding claims, characterized in that the tooth tips (26) of the teeth (24) are formed substantially flat and extend in the width direction substantially perpendicular to a surface which serves as a cutting edge (34) and extends downwards in the longitudinal direction of the respective tooth (24), wherein an end (36) of the respective tooth tip (26) opposite the cutting edge (34) is rounded.

5. Blade according to one of the preceding claims, characterized in that the tooth tips (26) have an edge (28) which is formed substantially linearly, wherein their end portions (30, 30') are formed substantially perpendicular to the edge (28) or formed partially and / or completely rounded, and wherein a region (30, 30') of the tooth tips (26) is formed substantially perpendicular to the edge (28).

6. Blade according to one of claims 1 to 4, characterized in that the tooth tips (26) have a rounded edge (28) and / or a wavy edge (28).

7. Blade set for a hair clipper (10), which has a base body (12) and a blade set (14) fixedly connected thereto, the blade set (14) having a fixed blade (16) and a movable blade (18) according to one of claims 1-6.

8. Blade set according to claim 7, characterized in that the distance (A) between the adjacent teeth (24) is at least three times as large as the width (B) of the tooth tips (26) of the teeth (24) of the movable blade (18).

9. Blade set according to one of the claims 7 or 8, characterized in that each individual tooth (24) extends pointedly in the direction of the tooth end (22) and in particular in the form of a truncated pyramid.

10. Blade set according to any one of claims 7 to 9, characterized in that the ratio between the width (B) of the tooth tips (26) of the teeth (24) of the movable blade (18) and the width (B') of a tooth base (32) is approximately 1:2.

11. A hair clipper (10) comprising a base body (12) and a blade set (14) connected thereto according to any one of claims 7 to 10.

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