Field of the invention

The invention relates to a cutting set for a hair clipper wherein tooth elements are or a cutting edge is wave-shaped.

Prior Art

Multiple hair clippers with different blade sets are known from the art. For example, US 7,841,901 B2 discloses a blade set for a hair clipper comprising at least one stationary blade with multiple stationary blade teeth and at least one movable blade with multiple stationary blade teeth, which are configured to laterally move back and forth relative to the at least one stationary blade for cutting hairs. The movable blade contains a set of long teeth, which are configured to cut hairs over the width of the movable blade, and a set of short teeth, which are configure to cut hairs over the width of the movable blade, if a feed speed of the hair clipper exceeds a specific speed.

US 5,933,953 discloses a clipper for cutting hair strands including a blade set which has a stationary blade having a plurality of stationary blade teeth arranged a row so that hair strands enter between adjacent stationary teeth as the blade set moves through the hair strands. The stationary blade teeth have angled side cutting edges and tips, and the side cutting edges of adjacent teeth form roots where they intersect. A moving blade has a plurality of moving blade teeth which are also arranged in a row. The moving blade teeth complement the stationary blade teeth and pass across the stationary blade teeth in use to cut some of the hair strands. The moving blade teeth are relatively short, and preferably have tips which are flat. The moving blade teeth are separated by blade-like edge surfaces which are oriented in the direction of movement of the moving blade and are capable of cutting some of the hair strands which enter between the stationary blade teeth. The knife-like blade edges form a first line which is between a second line formed by the stationary blade teeth roots and a third line formed by the stationary blade teeth tips.

With these hair clippers a focus is on the cutting of hairs each with the same length. Thus, with such hair clippers, the cutting of a transition is difficult because minor cutting failures in the transition immediately stand out. Summary of the invention

The object of the present invention is to provide a blade arrangement, which simplifies the cutting of transitions in such a way that even non-professional users can create a good-looking transition.

The object is solved by a blade arrangement according to claim 1. The dependent claims contain further developments of the invention.

A blade arrangement for a hair clipper according to the present invention comprises a comb with a frontal edge, which is configured with tooth elements; a blade with a frontal cutting edge, which is configured with tooth elements, wherein the cutting edge is downwardly sloped at its front end towards the lower cutting edge, and wherein the blade is configured to be movable relative to the comb; a coupling device, which connects the comb and the blade movably relative to each other; and a pretension element, which preloads the comb and the blade towards one another wherein the cutting edge of the blade is construed in a wave shape, wherein the cutting edge of the blade (40, 50, 60, 70) comprises at least three tooth elements (46, 56, 66, 76) of different lengths and the individual tooth elements (46, 56, 66, 76) are irregularly curved shaped or the frontal cutting edge of the blade comprises at least three tooth elements of different lengths and/or the edges of the individual tooth elements are curved shaped corresponding to the wave shape. Via the tooth elements of different lengths and by the curved edges of the tooth elements, the hairs are cut with a slightly different length, which improves the look of the cut within the transition significantly, without special training.

Preferably, one wave extends across at least four tooth elements from one highest point to another highest point, further preferred across five or six and/or across maximum fifteen tooth elements, particularly preferred across thirteen or ten. In particular, the height from the highest tooth element to the lowest tooth element or from wave tip to wave valley is between 1 mm and 4 mm, preferably maximum 3 mm, more preferably maximum 2 mm. The wave tip is the point of the wave that is furthest forward. The wave valley is the point of the wave that is furthest backward.

Preferably, the wave shape is configured to be uniform, whereby a more uniform cutting of individual different lengths of hair can be achieved. The outermost lateral tooth elements can be configured as a wave tip. Thus, a uniform and especially symmetrical blade arrangement can be established, which simplifies the production.

In particular, the cutting edges, which are positioned closer to the front are thinner than the cutting edges that are positioned further back.

Further, the frontal cutting edge of the upper blade can comprise at least four tooth elements of different lengths, preferably five or six, but maximum ten.

Preferably, the tooth elements are arranged according to their length in ascending and descending order. Thus, the look of the cutting within the transition becomes more uniform and better looking. In another preferred embodiment, the tooth elements are arranged irregular with respect to their length.

Description of the figures

Figure 1 displays an explosion view of a blade arrangement with an enlarged view of the tooth elements; Figure 2 displays an isometric view of the mounting face of the blade arrangement of figure 1 in the mounted state with an enlarged view of the tooth elements;

Figure 3a displays an isometric view of the upper side of the comb;

Figure 3b displays a view of the lower side of the comb;

Figure 3c displays a side view of the comb of figure 3a; Figure 4a displays an isometric view of the lower side of a first embodiment of the blade;

Figure 4b displays a view of the upper side of the blade of figure 4a;

Figure 4c displays a view of the lower side of the blade of figure 4a;

Figure 4d displays a side view of the blade of figure 4a;

Figure 4e displays a rear view of the blade of figure 4a; Figure 4f displays a front view of the tooth elements of the blade displayed in figure 4a;

Figure 5a displays an isometric view of the lower side of a second embodiment of the blade;

Figure 5b displays a view of the upper side of the blade of figure 5a;

Figure 5c displays a view of the lower side of the blade of figure 5a;

Figure 6a displays an isometric view of the lower side of a third embodiment of the blade;

Figure 6b displays a view of the upper side of the blade of figure 6a;

Figure 6c displays a view of the lower side of the blade of figure 6a;

Figure 7a displays an isometric view of the lower side of a fourth embodiment of the blade;

Figure 7b displays a view of the upper side of the blade of figure 7a;

Figure 7c displays a view of the lower side of the blade of figure 7a.

Preferred embodiments

In the following, the direction “frontal” indicates a direction of the tooth elements (e.g. in figure 4b on the top side) and “rear” indicates the opposite direction (in figure 4b on the lower side).

Figure 1 displays an explosion view of the components of a blade arrangement 10 according to the present invention. In figure 2, the blade arrangement is displayed in the mounted state. The upper side of the figures 1 and 2 is placed on the handle and attached to a drive, which generates an oscillating movement. The motor for the drive is placed in the handle, as it is common for hair clippers.

A blade arrangement 10 comprises a comb 30, a blade 40, 50, 60, 70, a pretension element 16, which is indicated as spring element 16, and a connection device. The connection device serves to connect the comb 30 and the upper blade 40, 50, 60, 70 and comprises multiple components, whose functions and number can vary. In the displayed embodiment, the connection device comprises a retaining means 12, which is attached to the comb 30 with fixation means 13 and which is placed on the handle of the hair clipper and attached thereto e.g. with a click mechanism. Then, the retaining means 12 also retains the other components of the connection device on the comb 30. Further, the connection device comprises a slide 14, which is connected to the blade 40, 50, 60, 70 and which enables the forward and backward shoving of the blade 40, 50, 60, 70 to set cutting properties (see arrow A in figure 2), an actuating element 18, by which the slide 14 is actuated, a spring element 16, which is fixed in a bore 42 of the blade by means of hook-shaped ends 17 and which presses the blade against the comb 30, and a transmission element 20, which transmits the oscillating movement of the drive to the blade 40, 50, 60, 70. In particular, the oscillation takes place in a lateral direction (see arrow B in figure 2). The transmission element 20 can be firmly connected to the blade 40, 50, 60, 70.

In figure 2, the blade arrangement 10 is displayed in a mounted state, wherein all components of the blade arrangement 10 are installed. In figure 1 and figure 2, the embodiment of the blade 40 of figure 4 is displayed. This is to be understood to be just exemplarily and the described blade arrangement can be used with any blade.

In figure 3, the comb 30 is displayed. Figure 3a is a view of the upper side of the comb 30, wherein the blade arrangement 10 is attached to a handle of the hair clipper. The comb 30 comprises a front edge 34, which comprises tooth elements 36. Further, the comb 30 comprises two bores 38, to which the connection device is fixed with fixation means 13. The tooth elements 36 are preferably tapered, whereby the lower side (see figure 3b), to which the blade 40, 50, 60, 70 abuts, is shaped flatly so as to not impair the cut. This means that the inclination 31 is present at the upper side and can preferably also begin already before the tooth elements.

Figure 3c is a side view of the comb 30. The bores 38 are positioned in recesses 37. Further, a recess 35 is also positioned in front of the tooth elements 36. In these recesses, the blades 40, 50, 60, 70 are inserted in such a way that they are movable forwardly and backwardly by the actuating element and laterally by the drive.

In figures 4 to 7, different embodiments of blade arrangements are displayed. The general structure of the blades 40, 50, 60, 70 is the same. Thus, the following description applies for all blades 50, 60, 70. In figures 4a, 5a, 6a and 7a an isometric view of the lower side of the blades 40, 50, 60, 70 is displayed. Figures 4b, 5b, 6b and 7b are views of the upper side of the blades 50, 50, 60, 70, which abut the comb 30 and figures 4c, 5c, 6c and 7c are views of the lower side of the blades 40, 50, 60, 70. In the blade 40, 50, 60, 70, a fixation recess 41, 51, 61, 71 for fixing the transmission element 20 is positioned. On both sides of the fixation recess 41, 51, 61, 71, the bores 42, 52, 62, 72 are configured for the spring element 16.

Figure 4d shows a side view of the blade 40. From the side, it can be seen that the blade 40 has two bearing pedestals 45, which are received in the recesses 35, 37 in the assembled state. The pedestals 45 and the recesses 35, 37 are configured in such a way as to ensure forward/rearward movement of the blade 40 by the actuating element 18. The connecting part 43 the bridge so to speak, connects the pedestals of the blade 40 to each other. Figure 4e is a rear view of the blade 40 and 4f is a front view showing the cutting edges of the tooth elements 46. These views are not shown in the embodiments shown in Figures 5, 6 and 7. However, these blades 50, 60, 70 are formed accordingly. The tooth elements 46, 56, 66, 76 are positioned at the frontal edge 44, 54, 64, 74 of the blade 40. The tooth elements 46, 56, 66, 76 are generally configured in a wave shape, although they can also be arranged in an irregular arrangement, as will be described later. This means that the extension towards the front (on the top side in figure 4b) of the individual tooth elements 46 is in particular fit to a uniform wave shape. Thereby, the tooth elements 46, 56, 66, 76 have different lengths towards the front, so that there are at least three different lengths of tooth elements 46, 56, 66, 76 (short, medium-sized, long) and an wave reaches from one longest tooth element 46, 56, 66, 76 to another longest tooth element 46, 56, 66, 76. The outward tooth elements 46, 56, 66, 76 are preferably also the largest tooth elements 46, 56, 66, 76, so that the wave always ends at a maximum. Further, it is not necessary to place a tooth element 46, 56, 66, 76 at every maximum of a wave line. The tooth elements 46, 56, 66, 76 comprise cutting edges 48, 58, 68, 78 at their frontal edges, which are inclined at their lower side (the side which is directed away from the comb 30). This is shown from the side in figure 4d. An inclination of the cutting edges 48, 58, 68, 78 is also displayed in the frontal views of figures 4c, 5c, 6c and 7c. The wave shapes are preferably uniform (this means always the same repetitively) and more preferably also formed symmetrical to a line, which is vertical to the maximum of the wave.

In the embodiment of figure 4, not only the course of the tooth elements 46 is adapted to this wave but also the geometry of the cutting edges 48 of the individual tooth elements 46 whereby these cutting edges 48 are curvedly formed according to the wave (see the magnification in figures 1 and 2). In the embodiment of figure 4, each wave extends across three or four tooth elements 46 and thus is a “short wave”. Because of the adjustment according to the wave, there are at least three tooth elements 46 with different lengths although the specific configuration of the tooth elements 46 can lead to a greater variety. For example, tooth element 46’ has the same length as tooth element 46”, but a different curvature. In figures 4b, 5b and 6b, a wave is displayed, which is aligned the cutting edges 48 of the tooth elements 46. It can be seen in which way the cutting edges 48 are configured according to the wave line. Here, the “short wave” is displayed but the cutting edges of the “medium-sized wave” and “long wave”, which are described in the following, are configured with corresponding wave lines.

In figure 5, a second embodiment of the tooth elements is displayed. In general, the configuration of the blade 50 is the same as in figure 4, only in this case, the wave shape exhibits a longer wave, which means that one wave extends across five, six or seven tooth elements 56 and is therefore a “medium-sized wave”. Also in this embodiment, the cutting edges 58 are configured with a curved shape according to the wave line.

In figure 6, a third embodiment of the tooth elements is displayed. Also in this case, the configuration of the blade 60 is the same as in the first embodiment, which is displayed in figure 4. Compared to the “medium-sized wave” of figure 5, here the shape of the wave exhibits a longer wave. This means that here, the wave contains ten, eleven or even more tooth elements 66. This shape of the wave is called a “long wave”. Also in this embodiment, the cutting edges 58 are configured with a curved shape according to the wave line.

In figure 7, a further embodiment is displayed. Analogous to the previous embodiments, the configuration of the blade 70 is also the same as in the first embodiment, which is displayed in figure 4. In this case however, the cutting edges 78 of the tooth elements 76 are not curved but the shape of the wave is placed through the center of the cutting edges 78. Therefore, there are tooth elements with a cutting edge configured to have different lengths, which are not curved but configured to be straight. With these tooth elements 76, a wave line is recreated wherein two adjacent waves always “share” a maximum. What is displayed is a preferred embodiment of the blade 70, wherein one wave always has five tooth elements. This means that the wave line starts with a long tooth element 76’, followed by a medium-sized tooth element 76”, a short tooth element 76”’ and then a medium-sized tooth element 76” again. The closing long tooth element 76’ is also the starting point for the adjacent wave. This embodiment can also be applied to longer wave shapes by adding further tooth elements 76 with different lengths (e.g. a tooth element, which is longer as the medium-sized tooth element 76” but shorter than the long tooth element 76’).

In another embodiment, the tooth elements 46, 56, 66, 76 can be arranged in an irregular or arbitrary arrangement. That is, the sequence of the individual teeth does not need to be arranged with respect of their size, but can be arranged completely irregular so that a big tooth can be adjacent to a small tooth on the one side and a medium or another big tooth on the other side (or any other combination of sizes). Additionally, the shape of the frontal cutting edge is preferably not aligned in a uniform waveform, but a plurality of individual teeth comprises a cutting edge that is irregular or arbitrary curved and does in particular comprise a non-straight shape. For example, although the embodiment in Figure 4 is constructed to be aligned with a wave, the single teeth already comprise an irregular curved shape due to the short wavelength. A design for such an irregular shaped frontal cutting edge could be derived by starting with the form of the regularly shaped tooth elements shown in Figures 4c, 5c and 6c and mix their arrangement so that the individual teeth change place with each other. Then the individual teeth would each have curved cutting edges which are not aligned with the actual shape of a wave, but also achieve the advantage of the invention of cutting hair in different length as described previously. Basically, each individual tooth can form from its left side to its right side an individual cutting edge including a straight line, an inclined line and any curved shape, so that the overall design of the frontal cutting edge of the blade is irregularly shaped.

Reference sign list

Blade arrangement 10 Retaining means 12 Fixation means 13 Slide 14

Pretension element 16 Hook-shaped ends 17 Actuating element 18 Transmission element 20 Comb 30 Inclination 31 Edge 34 Recess 35

Tooth element comb 36

Recess 37

Bore comb 38

Blade 40, 50, 60, 70

Fixation recess 41, 51, 61, 71

Bore 42, 52, 62, 72

Bridge 43, 53, 63, 73

Edge 44, 54, 64, 74

Pedestal 45, 55, 65, 75

Tooth element blade 46, 56, 66, 76

Tooth element 46’

Tooth element 46”

Cutting edge tooth element 48, 58, 68, 78 Long tooth element 76’

Medium-sized tooth element 76”

Short tooth element 76”’