FIELD OF THE INVENTION
-
The present invention relates to an edge guard tooth for a guard blade of a hair cutting device, a corresponding guard blade and a corresponding hair cutting device.
BACKGROUND OF THE INVENTION
-
In the field of cutting and grooming hair, cutter blades are often used having a plurality of cutter teeth for cutting hair usually via a reciprocal movement of the cutter teeth. The cutter blade captures hair to be cut between adjacent teeth when the cutter blade is moved along a user's skin and sharp edges provided at the cutter teeth shear off or cut the hair via the reciprocal sawing movement perpendicular to the movement of the cutter blade along the skin. Since the sharp cutter teeth are to be brought in the vicinity of a user's skin for haircutting, they must be usually shielded by respective guarding elements for protecting the skin from a direct contact with the sharp cutter teeth. Various guard elements are known in the art, which attempt to space apart the cutter teeth from the skin. However, known guard elements are often bulky and may accordingly adversely impact the hair cut efficiency. Furthermore, the known guard elements may provide only inadequate skin protection and may harm the skin during the haircutting process. That is, users often experience undesirable skin irritation and discomfort during hair cutting, for instance due to suboptimal design of the guard elements.
-
Thus, it is an object of the present invention to provide an improved configuration, which addresses the above noted drawbacks of the prior art.
SUMMARY OF THE INVENTION
-
The above noted problems are at least partially solved or alleviated by the subject matter of the independent claims of the present disclosure, wherein further preferred embodiments are expressed by the dependent claims.
-
The present invention relates to an edge guard tooth for a guard blade of a hair cutting device, the edge guard tooth extending in a lateral direction from the guard blade, wherein the edge guard tooth is arrangeable at one or both outer ends of the guard blade in a width direction perpendicular to the lateral direction, wherein the edge guard tooth comprises a first surface and a second surface each extending essentially in the lateral direction and in the width direction, wherein the second surface is arranged between the first surface and an outer portion of the edge guard tooth, wherein the first surface is arranged at a first height perpendicular to the lateral direction and the width direction, and wherein the second surface is arranged at a second height which is lower than the first height.
-
Thus, an initial skin contact with the edge guard tooth could be achieved via the second surface having a lower height during the operation haircutting. A lower height of the second surface may enable the provision a less bulky edge portion and therefore an improved guidance of skin along a smaller contact surface. This may facilitate the handling of a haircutting device provided with one or more of the edge guard teeth described herein during haircutting operation and accordingly may improve the efficiency thereof. In particular, friction of the skin with the second contact surface could be accordingly reduced and therefore irritations of the skin may be prevented.
-
The edge guard tooth according to the present invention also addresses the problem of high skin pressures leading to skin doming at the contact sides of the guard blade during haircutting operation due to the pressure applied by the user. Herein, skin is often uncomfortably elevated to a dome by a contact with the guard blade when the guard blade is pushed against and along the skin. The skin doming particularly occurs at the edges of the skin, where the skin is the least uniformly supported by the guard blade. The reduced height of the second surface may accordingly allow a guidance of the skin along the edge guard tooth while disadvantageous skin doming could be prevented.
-
Furthermore, the first surface may provide guidance of a cutter blade, wherein the first surface and the respective cutter blade arranged thereon may be accordingly spaced with respect to an outer portion of the edge guard tooth, wherein the skin contacts the edge guard tooth. In other words, an undesirable skin contact with the first surface may be prevented.
-
The first surface may be suitably formed to carry the cutter blade to allow a smooth movement thereof on the first surface. Different thereof, the second surface may be formed differently, as it may not be required to carry the cutter blade on the second surface and to allow a respective movement thereof. This may facilitate the manufacturing of the edge guard tooth.
-
Furthermore, the second surface may be optimized for a skin contact, e.g. made be smoothed accordingly for preventing sharp edges. Thus, harm and irritation to the skin during haircutting operation may be further minimized. In other words, the first surface may be optimized for achieving an efficient haircutting operation, whereas the second surface may be optimized for skin protection. No further elements for protecting the skin may be needed, which may simplify a setup of a respective haircutting device comprising a guard blade having one or more of the edge guard teeth according to the present invention.
-
A haircutting device may be generally understood as any device that is able to cut, groom or trim hair. The haircutting device may comprise a cutter blade that is propellable, e.g. via an electric motor. The cutter blade may perform a reciprocal sawing movement with respect to the guard blade for cutting hair.
-
The edge guard tooth may be manufactured by any suitable mechanically resilient material. The edge guard tooth may be for instance made of or comprising for instance a metal material, a plastic material and/or a composite material. The edge guard tooth may be suitably dimensioned and shaped to protect a user from contacting one or more cutter teeth of the cutter blade of the haircutting device. In particular, as will also be described in detail further below, the edge guard tooth may extend beyond the extension direction of a cutter tooth to contact the skin during use of the haircutting device, thus preventing a contact of the skin with the cutter blade.
-
The guard blade may comprise a plurality of guard teeth arranged adjacent to each other in a spaced manner for collecting hair in respective cavities created in between the guard teeth. The respective guard teeth may be equally or non-equally distanced from each other. The guard teeth may include one or more edge guard teeth as described herein and one or more inner guard teeth arranged between the edge guard teeth along the extension direction of the guard blade, e.g. in the width direction.
-
The first surface may be arranged to face an oppositely arranged cutter tooth. For instance, the cutter tooth may be arranged above the guard tooth in a height direction. Hence, the cutter tooth may be spaced from the skin to be contacted by the guard tooth in the height direction. The second surface may also be arranged in the lateral direction beyond the first surface. In some configurations, the second surface may be distanced from the cutter tooth.
-
A lateral direction may be the direction along which the haircutting device is moved during use. A width direction may be the direction perpendicular to the lateral direction. The lateral direction and the width direction may define a plane in which a bottom side of the guard blade may essentially extend. Perpendicular to the lateral and the width direction, a height direction may be defined. It will be appreciated that the directions defined herein are only exemplarily denoted as "lateral", "width" and "height" directions to explain the relative arrangement and spatial relationships of features and may also be denoted differently, as desired.
-
The guard blade may be a plate-shaped element extending essentially in the width direction perpendicular to the lateral direction and having a certain length in the lateral direction while having a minor extension in the height direction perpendicular to both, the lateral direction and the width direction. The guard blade may comprise one or more edge guard teeth arranged at one or more outer edges of the guard blade in the width direction and may comprise one or more inner guard teeth arranged between the respective outer guard teeth in the width direction.
-
An extension of the edge guard tooth in the lateral direction and/or the width direction may not be construed to a strict linear extension along the respective straight axes of the extension directions but may include for instance partial inclinations of one or more portions of the edge guard tooth with respect to the lateral direction and/or the width direction.
-
Even though only a two-surface arrangement including the first surface and the second surface is described, the present invention is not delimited thereto. That is, different configurations may provide one or more further surfaces arranged for instance between the first surface and the second surface. Furthermore, even though the first surface and the second surface may essentially extend in a plane spanned by the lateral direction and the width direction, it may be well conceivable that the surfaces may also extend at least partially in an inclined manner to this plane. Likewise, also potential further additional surfaces may be provided in an inclined manner.
-
In a preferred embodiment, a height difference between the first surface and the second surface is in a range of 0.01 mm to 5 mm, preferably in a range of 0.05 mm to 0.5 mm, more preferably about 0.1 mm.
-
Thus, an improved stability of the guard tooth in the height direction may achieved while an improved skin protection and haircutting properties of the haircutting device could be obtained. The height difference may be suitably selected in the above ranges, such that the cutter blade may be arranged above the edge guard tooth at the first surface cannot interfere with the second surface. At the same time, stability of the edge guard tooth may be not disadvantageously impaired. The height difference may vary in the above noted ranges or may not vary. In other configurations, the height difference may also be generally larger or smaller, as desired.
-
In another configuration, the height difference between the first surface and the second surface may be generally larger than 0.01 mm. In another configuration, the height difference between the first surface and the second surface may be provided relative to thickness of the guard blade in the height direction, wherein the height difference may be for instance up to half of the thickness of the guard blade in the height direction.
-
In a preferred embodiment, the first surface includes a cutter blade running surface adapted to face a cutter blade arrangeable above the guard blade.
-
Thus, an efficient haircutting operation may be achieved. In particular, the cutter blade running surface may be suitably prepared, e.g. ground, to facilitate a smooth and frictionless running of the cutter blade.
-
In one configuration, the cutter blade may at least partially contact the cutter blade running surface. The cutter blade running surface may be accordingly adapted to face and/or contact at least partially a cutter tooth contact surface of a cutter tooth of the cutter blade, as described herein. That is, the cutter tooth and/or another part of the cutter blade may run in an at least partially contacting manner along the cutter blade running surface of the edge guard tooth. The cutter blade running surface may be provided oppositely to the contact surface of the guard blade adapted to contact the skin. Thus, a contact of the cutter blade with skin could be advantageously prevented.
-
In another configuration, the cutter blade running surface of the edge guard tooth may face only the plane at which the cutter blade moves but may not immediately face the cutter blade and/or may not come into contact with the cutter blade. This may be for instance the case when the cutter blade may only have a minor reciprocal movement along the guard blade in the width direction and may accordingly not reach the one or more edge guard teeth. Further, the first surface may be in the same plane as the cutter blade running surface.
-
In a preferred embodiment, the first surface is arranged at a first edge guard tooth portion connectable to a base portion of the guard blade, and the second surface is arranged at a second edge guard tooth portion extending from the first edge guard tooth portion in the lateral direction and/or the width direction to the outer portion of the edge guard tooth.
-
Thus, skin safety during haircutting operation could be enhanced since the second surface may suitably contact the skin during haircutting operation, while contact of the skin with the first surface may be advantageously prevented. In other words, the second edge guard tooth portion may suitably space the first edge guard tooth portion bearing the reciprocally moving cutter blade from regions of the edge guard tooth at which a potential skin contact might occur during haircutting operation.
-
For instance, the second surface may extend from the first edge guard tooth portion essentially only in one direction, e.g. in the lateral direction or in the width direction or in both, the lateral and the width directions.
-
The guard blade may be integrally formed, such that the edge guard tooth is integrally connected with the base portion of the guard blade. However, the base portion and the edge guard tooth may also be separate parts connected to each other.
-
In a preferred embodiment, a transition portion is provided between the first edge guard tooth portion and the second edge guard tooth portion, the transition portion having a transition surface connecting the first surface and the second surface, wherein the transition surface comprises a height continuously decreasing from the first height at a connection with the first surface to the second height at a connection with the second surface.
-
Thus, the height difference between the first surface and the second surface may be smoothly bridged. This may further increase protection of the skin since a steep height difference between the first surface and the second surface and accordingly sharp edges may be avoided.
-
The height of the transition surface may continuously decrease from the first height to the second height. However, in different embodiments, the transition surface may also comprise portions of non-continuous height. That is, the transition surface may also comprise at least partially one or more height increasing portions or one or more continuous height portions. The slope of the transition surface may include any desired form, e.g. a linear or a curved slope and/or a combination thereof.
-
The transition surface may be suitably shaped such that a connection edge, as described in detail further below, at a connection interface between the transition surface and the first surface and/or an edge at a connection interface between the transition surface and the second surface may be preferably as smooth as possible.
-
In a further embodiment, the first surface and the second surface contact each other at a connection edge, wherein a distance from the connection edge to a distal end of the edge guard tooth is in a range of at least 0.1 mm to 5 mm, preferably in a range of at least 0.3 mm to 2 mm and more preferably of about at least 0.5 mm.
-
Thus, an improved skin protection could be obtained. The distance from the connection edge to the distal end of the edge guard tooth may be suitably selected to enable a proper skin and hair guidance along the lateral direction. Furthermore, the length may be suitably set to achieve a desired distancing of skin approaching the connection edge from the front or side, e.g. during use of the hair cutting device.
-
In another configuration, a distance from the connection edge to the distal end of the edge guard tooth may be in a range of at least 0.1 mm to the full width or length of the edge guard tooth, and preferably in a range of at least 0.3 mm to the half width or length of the edge guard tooth. In other configurations, the distance may also be generally larger or smaller, as desired.
-
In other words, since the connection edge is retracted from the distal end of the edge guard tooth by a respective distance, a contact of the connection edge with the skin of a user during haircutting operation could be beneficially prevented.
-
In case a transition portion is provided, the connection edge may be provided either at the interface between the transition surface and the first surface or at the interface between the transition surface and the second surface. The respective distance from the connection edge to the distal end may accordingly extend from the connection edge provided at the respective interfaces to the transition portion to the distal end.
-
The connection edge may be provided as a non-rounded edge or as a rounded edge.
-
In a preferred embodiment, the second edge guard tooth portion comprises a contact surface for contacting skin and hair comprising one or more of a front contact surface arranged at least partially at a front of the guard blade, an outer contact surface arranged at least partially at an outer side of the guard blade, and/or an inner contact surface facing at least partially an inner side of the guard blade, wherein the second surface abuts to one or more of the front contact surface, the outer contact surface and/or the inner contact surface at a first contact portion comprising a first rounded edge.
-
Accordingly, the contact surface may be suitably formed, e.g. surface treated, to allow a frictionless movement of the skin along the contact surface. This may further reduce skin irritation during the haircutting operation. The contact surface may be understood as the surface of the edge guard tooth that may preferably contact the skin during haircutting operation.
-
The second edge guard tooth portion may comprise a front contact surface arranged at least partially at a front of the guard blade, an outer contact surface arranged at least partially at an outer side of the guard blade, and an inner contact surface facing at least partially an inner side of the guard blade. In other configurations, only one or two of the above noted contact surfaces may be provided.
-
The second surface may abut the front contact surface, the outer contact surface and the inner contact surface at a first contact portion comprising a first rounded edge. In other words, the outer contacting part of the upper surface of the edge guard tooth, which may be formed by the second surface, may be connected to respective perpendicular contact surfaces via the first rounded edge. Thus, skin contacting the connection between the respective contact surfaces and the second surface may only experience a low friction due to the first rounded edge. This may accordingly further reduce irritation of the skin and may facilitate a guidance of the skin along the inner, outer and front contact surfaces and the second surface. In other configurations, only portions of the connection between the second surface and the front contact surface, the outer contact surface and the inner contact surface may be provided with the first rounded edge.
-
The front contact surface, the outer contact surface and the inner contact surface may extend essentially perpendicular to the second surface. However, in different configurations, the front contact surface, the outer contact surface and/or the inner contact surface may be at least partially inclined such that they do not extend in a straight perpendicular manner.
-
The outer contact surface may be essentially the contact surface of the edge guard tooth that is arranged at the outermost width extension direction of the guard blade. The inner contact surface may be essentially the contact surface of the edge guard tooth that is arranged opposite to the outer contact surface and may face towards an inner portion of the edge guard tooth in the width direction. This may be the direction at which the inner guard teeth are arranged. Accordingly, the inner contact surface may form, together with an adjacent inner guard tooth, a part of a cavity in which hair to be cut could be captured.
-
In a preferred embodiment, the second edge guard tooth portion comprises the front contact surface and the inner contact surface, and the front contact surface and the inner contact surface abut at a second contact portion comprising a second rounded edge.
-
Thus, skin contacting the connection between the front contact surface and the inner contact surface may only experience a low friction due to the second rounded edge. This may accordingly reduce irritation of the skin and may facilitate a guidance of the skin along the respective front contact surface and inner contact surface. In some configurations, the second rounded edge may accordingly extend essentially in the height direction. In some configurations, only portions of the connection between the front contact surface and the inner contact surface are provided with the second rounded edge.
-
In a preferred embodiment, the contact surface comprises a base contact surface oppositely arranged at the edge guard tooth to the first and/or second surface in the height direction, wherein the base contact surface is essentially perpendicular to one or more of the front contact surface, the outer contact surface and/or the inner contact surface, wherein the base contact surface abuts one or more of the front contact surface, the outer contact surface and/or the inner contact surface at a third contact portion comprising a third rounded edge.
-
Thus, skin contacting the connection between the base contact surface and the front contact surface, the outer contact surface or the inner contact surface may only experience a low friction due to the third rounded edge. This may accordingly reduce irritation of the skin and may facilitate a guidance and deflection of the skin along the respective contact surfaces.
-
The outer contact surface may comprise the base contact surface oppositely arranged at the edge guard tooth to the first surface and the second surface in the height direction. Further, the base contact surface may be essentially perpendicular to the front contact surface, the outer contact surface and the inner contact surface, wherein the base contact surface may abut the front contact surface, the outer contact surface and the inner contact surface at the third contact portion comprising the third rounded edge. In other configurations, the base contact surface may only be oppositely arranged to one of the first surface or the second surface.
-
In further configurations, the base contact surface may be essentially perpendicular to only one or two of the front contact surface, the outer contact surface and the inner contact surface.
-
Likewise, in other configurations, the base contact surface may abut only one or two of the front contact surface, the outer contact surface and the inner contact surface at the third contact portion comprising the third rounded edge.
-
In other configurations, only portions of the connection between the base contact surface and the front contact surface, the outer contact surface or the inner contact surface may be provided with the third rounded edge.
-
In a preferred embodiment, one or more of the first rounded edge, the second rounded edge and/or the third rounded edge has a rounded edge curvature radius in a range of 0.1 mm to 1 mm, preferably in a range of 0.2 mm to 0.5 mm and more preferably of about 0.25 mm.
-
Thus, the pressure distribution to the skin may be further enhanced, and skin safety and comfort of use during haircutting operation may be further improved. In particular, guidance of the skin along the curved surfaces and edges may be facilitated when the haircutting device is moved along the skin, e.g. in the lateral direction. In this respect, if the curvature radius may be chosen too small, the advantageous effect of additional skin protection may not be sufficiently achieved. Similarly, if the curvature radius may be selected too large, the desired guidance of hair and skin may become difficult. Accordingly, the above noted curvature radius ranges may provide an optimum balance between improved skin protection and efficient hair and skin guidance and hair cutting.
-
One or more edges may comprise the same curvature radius. For instance, all rounded edges may comprise the same curvature radius. Or one or more rounded edges may comprise a different curvature radius, such that the first rounded edge may comprise a first curvature radius and the second rounded edge and/or the third rounded edge may comprise curvature radii different to the first curvature radius. In other configurations, the curvature radius may also be generally larger or smaller, as desired.
-
The rounded edges may include roundings extending, e.g. in the lateral direction, the width direction or the height direction. Thus, the hair and skin may be easily guided with a decreased friction along the contact surfaces of the edge guard tooth.
-
The edge guard tooth may have a laterally arranged distal end for contacting skin during use of the haircutting device. Rounded edges may be provided between the respective contact surfaces.
-
For instance, the second surface may abut the front contact surface with the first rounded edge of the first contact portion. Likewise, the base contact surface may abut the front contact surface with the third rounded edge of the third contact portion. The first rounded edge may have a rounded edge curvature radius and the third rounded edge may have another rounded edge curvature radius. The curvature radius of the first rounded edge and the curvature radius of the third rounded edge may be for instance the same. However, it will be understood that each of the rounded edge curvature radii described herein could be individually selected and therefore could also be at least partially different from each other.
-
The provision of rounded edges may generally increase the contact surface of the edge guard tooth at the respective portions and may accordingly reduce irritations and discomfort of the skin contacting the edges. Furthermore, the skin could be easily deflected with less friction. However, in different configurations, at least some of the rounded edges may be omitted or even no rounded edges may be provided at the edge guard tooth.
-
For instance, the second rounded edge may be provided essentially along the height direction. The first rounded edge at the outer top side of the edge guard tooth, the first rounded edge at the inner top side of the edge guard tooth and the corresponding third rounded edge at the outer bottom side of the edge guard tooth and the third rounded edge at the inner bottom side of the edge guard tooth may be provided essentially along the lateral direction. Finally, the first rounded edge at the top front side of the edge guard tooth and the corresponding the third rounded edge at the bottom front side of the edge guard tooth may be provided essentially along the width direction. However, in different configurations, at least some of the rounded edges may be omitted or even no rounded edges may be provided at the edge guard tooth.
-
In a preferred embodiment, the edge guard tooth comprises a contact surface transition portion between the front contact surface and the outer contact surface, wherein the contact surface transition portion has a contact surface curvature radius in a range of 0.1 mm to 4 mm, preferably in a range of 1 mm to 3 mm, more preferably about 2.4 mm.
-
Accordingly, the pressure distribution to the skin may be further enhanced, and skin safety and comfort of use during haircutting operation may be further improved. In particular, guidance of the skin along the curved front and outer surfaces of the edge guard tooth may be facilitated when the haircutting device is moved along the skin, e.g. in the lateral direction. In this way, skin contacting the front contact surface may be suitably deflected to the outer side of the edge guard tooth in a low frictional manner.
-
Since a curved shape is provided, the respective top and bottom edges described before may accordingly transition in a curved manner, e.g. continuously from the front side of the edge guard tooth to the outer side of the edge guard tooth. That is, the respective curved top and bottom edges, which may be rounded edges, may accordingly comprise continuously varying portions of extension in the width direction and in the lateral direction.
-
The contact surface transition portion may also be provided only partially, wherein part of the front contact surface may maintain its extension direction essentially perpendicular to the lateral direction and/or wherein part of the outer contact surface may maintain its extension direction essentially perpendicular to the width direction.
-
Furthermore, the transition portion may also comprise portions having multiple different contact surface curvature radii and/or straight portions with no curvature, as desired.
-
The present invention further relates to a guard blade of a hair cutting device, wherein the guard blade comprises a base portion and at least one edge guard tooth extending in a lateral direction therefrom, wherein the edge guard tooth is arranged at one or both outer ends of the guard blade in a width direction perpendicular to the lateral direction, wherein the edge guard tooth is an edge guard tooth according to the present invention.
-
The above explanations regarding any features and advantages concerning the edge guard tooth likewise apply to respective features of the guard blade. Thus, an improved guard blade may be provided which may exhibit an increased skin protection while allowing for an efficient haircutting operation.
-
The guard blade may be fixedly arranged in a housing of a haircutting device, such that a relative reciprocal movement of a cutter blade movably arranged in the housing of the haircutting device may accordingly allow for cutting or shearing off hair.
-
The guard blade may be a plate-shaped element extending essentially in the width direction perpendicular to the lateral direction and having a certain length in the lateral direction while having a minor extension in the height direction perpendicular to both, the lateral direction and the width direction.
-
The guard blade may comprise a base portion, from which the respective edge guard tooth extends in the lateral direction. The guard blade may be integrally formed, such that the edge guard tooth is integrally connected with the base portion of the guard blade. However, the base portion and the edge guard tooth may also be separate parts connected to each other. The guard blade may comprise one or more edge guard teeth arranged at one or more outer edges of the guard blade in the width direction and may comprise one or more inner guard teeth arranged between the respective outer guard teeth along the width direction.
-
The guard blade may be manufactured by any suitable mechanically resilient material. The guard blade may be for instance made of or comprising for instance a metal material, a plastic material and/or a composite material. The guard blade may be suitably dimensioned and shaped to protect a user from contacting one or more cutter teeth of a cutter blade of a haircutting device. In particular, the edge guard tooth may extend beyond the extension direction of a cutter tooth in the lateral direction and/or in the width direction to primarily contact the skin during use of the haircutting device and accordingly prevent a contact of the skin with the cutter blade.
-
The guard blade may comprise a contact surface being in contact with the skin during the haircutting operation. For instance, the guard blade may be provided at the bottom side of a haircutting device, wherein the bottom side may be pressed against a user's skin during the haircutting operation. It is noted that "top" and "bottom" are used herein merely to explain the relative arrangement of the features with respect to the haircutting device and is not construed to mean absolute arrangements. That is, if the hair cutting device is used in an upside-down manner, e.g. when hair of an underside of the chin is to be cut, the respective bottom surface of the haircutting device may accordingly face upwards to be pressed against the downward facing skin of a user for haircutting operation.
-
An intermediate reception cavity for receiving hair may be defined between each of a plurality of adjacent inner guard teeth and between each of the one or more edge guard teeth and the respective adjacent inner guard teeth. Hence, hair to be cut could be captured in the one or more cavities when the guard blade is moved along the lateral direction along the skin. It is noted that corresponding cavities may also be formed by corresponding adjacent cutter teeth of the cutter blade, which cavities of the inner guard teeth and cutter teeth may be aligned to form combined cavities for capturing hair. In particular, hair could be advantageously captured in the one or more reception cavities when the guard blade is moved in the lateral direction along the skin. The reception cavities may be similarly or differently shaped. For instance, adjacent teeth may form a U-shaped reception cavity or a V-shaped reception cavity. Thus, hair may be suitably guided to target portions of the guard teeth, e.g. at inner regions of the cavities where the hair cutting may occur. Other arbitrary forms are of course also conceivable dependent on the shape and arrangement of the adjacent teeth. The reception cavities should be generally large enough to receive one or more hairs.
-
In a preferred embodiment, at least one edge guard tooth of the guard blade protrudes, in the lateral direction, beyond at least one cutter tooth of a cutter blade movably arrangeable with respect to the guard blade.
-
Thus, an improved skin protection may be achieved since a contact between the skin and the one or more cutter teeth of the cutter blade may be prevented. Hence, the guard blade may be moved in a lateral direction along the skin during a haircutting operation, and the guard blade may accordingly contact the skin at one or more of the contact surfaces of the edge guard teeth instead of contacting reciprocally moving cutter teeth of the cutter blade. Thus, injuries of the skin could be efficiently prevented.
-
The present invention further relates to a hair cutting device comprising: a cutter blade movably connected to the hair cutting device, a guard blade connected to the hair cutting device, wherein the guard blade is a guard blade according to the present invention, or wherein the guard blade comprises at least one edge guard tooth according to the present invention.
-
The above explanations regarding any features and advantages concerning the edge guard tooth and the guard blade likewise apply to respective features of the hair cutting device. Accordingly, a haircutting device may be provided, which may allow for an improved skin protection while achieving an enhanced haircutting functionality. In particular, no further elements except the guard blade for protecting the skin may be needed, which may simplify a manufacturing and setup of the haircutting device comprising the guard blade having one or more of the edge guard tooth according to the present invention.
-
The haircutting device may be for instance an electrically driven handheld haircutting device.
-
The haircutting device may comprise a cutter blade that is propellable, e.g. via an electric motor. The cutter blade may perform a reciprocal movement with respect to the guard blade for cutting hair. However, the present invention is not delimited thereto. Thus, a haircutting device may be generally understood as any device that is able to cut, groom or trim hair.
-
The haircutting device may comprise a spring assembly that may be fixedly mounted on one side in a housing of the haircutting device. The other side of the spring assembly may be mounted to a driving bridge of the haircutting device, which in turn may be adapted to hold the cutter blade. Thus, a reciprocal movement of the cutter blade may be provided by the restoring forces of the spring assembly and a respective movement provided by an electric motor operatively coupled to the driving bridge.
-
The spring assembly may comprise an elastic element made of or comprising for instance an elastic material, such as for instance spring steel, which may enable to hold or press the cutter blade upon the guard blade. The driving bridge may mechanically connect the spring assembly with the cutter blade and may be made of or comprise for instance a plastic material.
-
The haircutting device may be moved along the skin e.g. in the lateral direction, and the reciprocal movement may occur perpendicular thereto in a width direction of the haircutting device. The haircutting device may be adapted to contact a skin of a user via a bottom side, which may be formed by a contact surface of the guard blade.
-
The guard blade may be connected to the haircutting device in an immovable manner. In another configuration, the guard blade may be connected to the haircutting device in a movable manner. The guard blade and the cutter blade may be connected to the haircutting device in a manner that a relative movement of the cutter blade and the guard blade could be achieved.
-
The cutter blade may be arranged directly above the guard blade. In another configuration the cutter blade may be arranged at least partially directly below the guard blade. In another configuration, the cutter blade may be arranged at least partially distanced from the guard blade.
-
As already explained above, it should be appreciated that the directions defined herein are only exemplarily denoted as "lateral", "width" and "height" to explain the relative arrangement and spatial relationships of the features and may also be denoted differently, as desired. Likewise, "top" and "bottom" are merely used to explain the relative arrangement of the features with respect to the haircutting device and is not construed to mean an absolute arrangements.
-
During use, the haircutting device may be pushed against the skin of a user and may accordingly contact the skin with an outer contact surface arranged e.g. at a bottom side of the hair cutting device. For performing hair cutting operation, the haircutting device may be moved in the pushed condition along the skin, which may be in the lateral direction. Consequently, during movement of the hair cutting device, the skin may be initially or primarily contacted by one or more of the contact surfaces of the one or more edge guard teeth.
-
In a preferred embodiment, the cutter blade comprises at least one cutter tooth extending from the cutter blade in a lateral direction and comprising a cutter tooth contact surface, wherein the cutter tooth contact surface is adapted to at least partially contact the cutter blade running surface during a relative movement of the cutter blade with respect to the guard blade.
-
Thus, an efficient hair cutting may be achieved while the skin may be suitably protected during the haircutting operation.
-
The cutter blade may be arranged in the housing, such that a reciprocal movement thereof may move the cutter teeth relatively to the edge guard teeth. When the haircutting device is moved in the lateral direction along the skin, hair to be cut may be captured between the cutter teeth and the guard teeth including one or more edge guard teeth and one or more inner guard teeth.
-
The relative movement may be a reciprocal or sawing movement of the cutter blade with respect to the guard blade. Hair may be accordingly cut due to the relative reciprocal movement of the cutter teeth with respect to the guard teeth. Suitable sharp edges may be accordingly provided at the cutter tooth contact surface and/or the blade running surface for enhancing the haircutting operation. Hair captured between a cutter tooth and an inner guard tooth, or an edge guard tooth may be accordingly easily sheared off.
-
Further features, examples, and advantages will become apparent from the following detailed description of preferred embodiments and the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
-
For a better understanding of the present invention, and to illustrate its practicality, figures are provided in the following and reference is made thereto. It should be understood that the figures represent only exemplary embodiments and thus in no way limit the scope of the claimed invention. Identical or like-acting elements are indicated throughout by the same reference signs. Any reference signs in the claims should not be construed as limiting the scope of the claims. The figures are merely schematic representations and serve only to illustrate examples of the disclosure. Further, as used herein, a hyphenated form of a reference sign refers to a specific embodiment of an element and the unhyphenated form of the reference numeral refers to the collective element. For example, a device "51-1" or "51-2" refers to an instance of a device class that can be collectively referred to as device "51" and each of which can be generically referred to as device "51".
-
In the accompanying drawings:
- Fig. 1 schematically illustrates a haircutting device according to an embodiment of the present invention;
- Fig. 2 schematically illustrates an enlarged view of an edge guard tooth of a guard blade according to an embodiment of the present invention;
- Fig. 3 schematically illustrates a cross-sectional view of an edge guard tooth according to an embodiment of the present invention and a cutter tooth.
DETAILED DESCRIPTION OF THE EMBODIMENTS
-
Fig. 1 illustrates a haircutting device 100 according to an embodiment of the present invention. The figure only shows the relevant parts of a haircutting device 100 for performing hair cutting operation. Further common parts, such as an electric motor to drive the parts, a handle to hold the haircutting device 100 etc. that may be additionally provided with the haircutting device 100 have been omitted from the figures but may of course be readily provided by the skilled person with the haircutting device 100 described herein.
-
In the depicted embodiment, the hair cutting device 100 comprises a cutter blade 10 movably connected to the hair cutting device 100, a guard blade 20 connected to the hair cutting device 100, wherein the guard blade 20 is a guard blade 20 as described in this specification, or wherein the guard blade 20 comprises at least one edge guard tooth 22 as described in this specification.
-
The guard blade 20 may be connected to the haircutting device 100 in an immovable manner. In another configuration, the guard blade 20 may be connected to the haircutting device 100 in a movable manner.
-
The cutter blade 10 comprises at least one cutter tooth 11 extending from the cutter blade 10 in a lateral direction L. As will also be described in detail further below with respect to Fig. 3, the cutter tooth comprises a cutter tooth contact surface 13, wherein the cutter tooth contact surface 13 is adapted to at least partially contact a cutter blade running surface 23 during a relative movement of the cutter blade 10 with respect to the guard blade 20. In other words, the cutter blade 10 is adapted to reciprocally move along the cutter blade running surface 23 of the guard blade 20, as indicated by the arrow 70.
-
The haircutting device 100 further comprises a spring assembly 1 that is fixedly mounted on one side in a housing 5 of the haircutting device 100. The other side of the spring assembly 1 is mounted to a driving bridge 3 of the haircutting device 100, which in turn is adapted to hold the cutter blade 10. Thus, a reciprocal movement 70 of the cutter blade 10 could be provided by the restoring forces of the spring assembly 1 and a respective movement provided by an electric motor (not depicted) operatively coupled to the driving bridge 3.
-
The spring assembly 1 comprises an elastic element made of spring steel, which holds and presses the cutter blade 10 upon the guard blade 20. The driving bridge 3 mechanically connects the spring assembly 1 with the cutter blade 10 and is made of a plastic material.
-
In the depicted embodiment, the guard blade 20 comprises a plurality of adjacent inner guard teeth 21, wherein an intermediate reception cavity 69 for receiving hair is defined between each of the plurality of adjacent inner guard teeth 21 and between each of the edge guard tooth 22 and the respective adjacent inner guard tooth 21.
-
Hence, hair to be cut could be captured in the one or more cavities 69 when the guard blade 20 is moved along the lateral direction L along the skin. With reference to Fig. 1, it is noted that corresponding cavities are also formed by adjacent cutter teeth 11, which cavities 69 of the inner guard teeth 21 and cutter teeth 11 may be aligned to form combined cavities for capturing hair. The inner guard teeth 21 may be equally distanced, as depicted in Figs. 1 and 2 or may be non-equally distanced in different embodiments.
-
In the depicted embodiment, the haircutting device 100 is moved along the skin in the lateral direction L, and the reciprocal movement 70 occurs perpendicular thereto in a width direction W of the haircutting device 100. The haircutting device 100 is adapted to contact a skin of a user via a bottom side 7.
-
In the depicted embodiment, the guard blade 20 is fixedly arranged in the housing 5, such that the reciprocal movement 70 of cutter teeth 11 relatively to the inner guard teeth 21 and the edge guard teeth 22 is enabled. When the haircutting device 100 is moved in the lateral direction L along the skin, hair to be cut could be captured between the cutter teeth 11 and guard teeth 21, 22 and could be sheared off or cut by the reciprocal movement 70 of the cutter teeth 11 relative to the inner guard teeth 21 and the edge guard teeth 22.
-
On the top surface of the guard blade 20, a cutter blade running surface 23 is provided, at which the bottom side of the cutter blade 10 contacts the guard blade 20 (cf. also Figs. 2 and 3). The cutter teeth 11 of the cutter blade 10 comprise a corresponding bottom cutter tooth contact surface 13 that contacts an upper surface of the inner guard teeth 21 and edge guard teeth 22 during the reciprocal movement. Hair captured between the cutter teeth 11 and the inner guard teeth 21 or between the cutter teeth 11 and the edge guard teeth 22 could be accordingly sheared off.
-
During haircutting operation, the haircutting device 100 is pushed against the skin of a user with the bottom side 7. Then, the haircutting device 100 is moved in a pushed condition along the skin, e.g. here in the lateral direction L. Accordingly, the skin contacts first a distal end 41 of the inner guard teeth 21 and the edge guard teeth 22 (cf. in detail Figs. 2 and 3).
-
At least one edge guard tooth 22 of the guard blade 20 protrudes, in the lateral direction L, beyond at least one cutter tooth 11 of the cutter blade 10 movably arrangeable with respect to the guard blade 20. It is noted that not every single cutter tooth 11 and inner guard tooth 21 and cavity 69 is labeled in Fig. 1 for representability reasons. The inner guard teeth 21 and outer edge guard teeth 22 are formed and arranged to generally prevent a contact of skin with the cutter teeth 11 arranged in the depicted embodiment above and laterally retracted from the distal end 41 of the inner guard teeth 21 and the edge guard teeth 22.
-
Furthermore, the cutter blade running surface 23 is arranged on a top side of the guard teeth 21. The cutter blade running surface 23 is accordingly formed such that a bottom side of a cutter blade 10 could contact the cutter blade running surface 23 and could be moved in a reciprocal manner parallel to a width direction W. Accordingly, hair captured in the reception cavities 69 could be properly cut or sheared off.
-
Fig. 2 schematically illustrates an enlarged view of an edge guard tooth 22 of a guard blade 20 according to an embodiment of the present invention. Fig. 2 represents an enlarged excerpt of the guard blade 20 showing the left guard tooth 20 at the left outer end 67-1 depicted in Fig. 1, however without depicting the further parts of the haircutting device 100. The guard blade 20 of the hair cutting device 100 comprises a base portion 37 and the at least one edge guard tooth 22 extending in a lateral direction L therefrom, wherein the edge guard tooth 22 is arranged at one or both outer ends 67 of the guard blade 20 in a width direction W perpendicular to the lateral direction L, wherein the edge guard tooth 22 is an edge guard tooth 22 as described in this specification.
-
The base portion 37 of the guard blade 20 may be a plate-shaped element extending essentially in the width direction W perpendicular to the lateral direction L and having a certain length in the lateral direction L while having a minor extension in the height direction H perpendicular to both, the lateral direction L and the width direction W. In the depicted embodiment, the inner guard teeth 21 and the edge guard teeth 22 are integrally connected to the base portion 37, i.e. they are made of one piece. It is noted that the detailed description of the configuration of the left outer end 67-1 of the guard blade 20 correspondingly applies to the right outer end 67-2 of the guard blade 20 depicted in Fig. 1.
-
Fig. 3 schematically illustrates a cross-sectional view of an edge guard tooth 22 according to an embodiment of the present invention and a cutter tooth 11 provided above the guard tooth 21 and protruding in the lateral direction L. The edge guard tooth 21 comprises at its top surface the cutter blade running surface 23 which contacts the cutter tooth contact surface 13 arranged at the bottom surface of the cutter tooth 11.
-
Figs. 2 and 3 particularly show an edge guard tooth 22 for a guard blade 20 of a hair cutting device 100, the edge guard tooth 22 extending in a lateral direction L from the guard blade 20, wherein the edge guard tooth 22 is arrangeable at one or both outer ends of the guard blade 20 in a width direction W perpendicular to the lateral direction L, wherein the edge guard tooth 22 comprises a first surface 25 and a second surface 27 each extending essentially in the lateral direction L and in the width direction W, wherein the second surface 27 is arranged between the first surface 25 and an outer portion 29 of the edge guard tooth 22, wherein the first surface 25 is arranged at a first height H1 perpendicular to the lateral direction L and the width direction W, and wherein the second surface 27 is arranged at a second height H2 which is lower than the first height H1.
-
Thus, an initial skin contact with the edge guard tooth 22 could be achieved during the operation haircutting via the second surface 27 having a lower height H2. A lower height of the second surface 27 enables the provision a less bulky edge portion and therefore an improved guidance of skin along a smaller contact surface. In particular, friction of the skin with the second contact surface could be accordingly reduced and therefore irritations of the skin may be prevented. Furthermore, the first surface 25 may provide guidance of a cutter blade 10, wherein the first surface 25 and the respective cutter blade 10 arranged thereon is accordingly spaced to an outer portion 29 of the edge guard tooth 22, wherein the skin contacts the edge guard tooth 22. In other words, an undesirable contact of the skin with the first surface 25 is prevented.
-
Furthermore, the first surface 25 may be suitably formed to carry the cutter blade 20 and in particular the cutter tooth 11 to allow a smooth movement thereof on the first surface 25, in particular on the cutter blade running surface 23. Different thereof, the second surface 27 may be formed differently, as it is not required to carry the cutter blade 20 and in particular the cutter tooth 11 and allow a respective movement thereof. This may facilitate the manufacturing of the edge guard tooth 22. Furthermore, the second surface 27 may be optimized for a skin contact, e.g. made be smoothed accordingly and to reduce or remove sharp edges. Thus, harm and irritation to the skin during haircutting operation may be further minimized. In other words, the first surface 25 may be optimized for achieving an efficient haircutting operation, whereas the second surface 27 may be optimized for skin protection.
-
Even though the embodiment depicted in the Figs. 2 and 3 show a two-surface arrangement including the first surface 25 and the second surface 27, the present invention is not delimited thereto. That is, different configurations may well provide one or more further intermediate portions comprising surfaces arranged for instance between the first surface 25 and the second surface 27. Furthermore, even though the first surface 25 and the second surface depicted the Figs. 2 and 3 essentially extend in a plane spanned by the lateral direction L and the width direction W, it is well conceivable that the surfaces may also extend at least partially in an inclined manner to this plane. Likewise, also potential further additional surfaces may be provided in an inclined manner.
-
A height difference between the first surface 25 and the second surface 27 is in a range of 0.01 mm to 5 mm, preferably in a range of 0.05 mm to 0.5 mm, more preferably about 0.1 mm. However, in different configurations also a different height difference between the first surface 25 and the second surface 27 may be provided. The height difference may be suitably chosen, such that the cutter blade 10 arranged above the edge guard tooth 22 at the first surface 25 does not interfere with the second surface 27.
-
As depicted in Figs. 2 and 3, the first surface 25 includes a cutter blade running surface 23 adapted to face a cutter blade 10 arrangeable above the guard blade 20. In Fig. 3, a configuration is shown, wherein the edge guard tooth 22 comprises at its first surface 25 the cutter blade running surface 23, which contacts the cutter tooth contact surface 13 arranged at the bottom surface of the cutter tooth 11.
-
In another configuration, the cutter blade 10 may not contact the cutter blade running surface 23 of the edge guard tooth 10. This may be for instance the case when the cutter blade 10 has only a minor reciprocal movement along the guard blade 20 in the width direction W and may accordingly not reach the one or more edge guard teeth 22. As depicted, the first surface 25 is in the same plane as the cutter blade running surface 23.
-
The first surface 25 is arranged at a first edge guard tooth portion 31 connectable to the base portion 37 of the guard blade 20, and the second surface 27 is arranged at a second edge guard tooth portion 35 extending from the first edge guard tooth portion 31 in the lateral direction L and/or the width direction W to the outer portion 29 of the edge guard tooth 22. In the embodiment depicted of Fig. 2, the second surface 27 extends from the first edge guard tooth portion 31 essentially in both, the lateral direction L and the width direction W. Thus, the second surface 27 may suitably contact the skin during haircutting operation, while contact of the skin with the first surface 25 is advantageously prevented.
-
A transition portion 33 is provided between the first edge guard tooth portion 31 and the second edge guard tooth portion 35, the transition portion 33 having a transition surface 34 connecting the first surface 25 and the second surface 27, wherein the transition surface 34 comprises a height H3 continuously decreasing from the first height H1 at a connection with the first surface 25 to the second height H2 at a connection with the second surface 27. Thus, the transition surface 34 of the transition portion 33 connects the first surface 25 with the second surface 27. In the depicted embodiment, the height H3 of the transition surface 34 continuously decreases from the first height H1 to the second height H2 along the lateral direction L. However, in different embodiments, the transition surface may comprise non-continuous height transition. That is, the transition surface 34 may also comprise at least partially one or more height increasing portions, or one or more continuous height portions.
-
The first surface 25 and the second surface 27 contact each other at a connection edge 39, wherein a distance D from the connection edge 39 to the distal end 41 of the edge guard tooth 22 is in a range of at least 0.1 mm to 5 mm, preferably in a range of at least 0.3 mm to 2 mm and more preferably of about at least 0.5 mm.
-
Likewise, in case a transition portion 33 is provided, the connection edge 39 could be provided either at the interface between the transition surface 34 and the first surface 25, which is the configuration depicted in Fig. 3, or at the interface between the transition surface 34 and the second surface 27. The respective distance D from the connection edge 39 to the distal end 41 may accordingly extend from the connection edge 39 provided at the respective interfaces to the transition portion 33 to the distal end 41, e.g. as depicted in Fig. 3.
-
In another configuration, a distance D from the connection edge 39 to the distal end 41 of the edge guard tooth 22 may be in a range of at least 0.1 mm to the full width or length of the edge guard tooth 22, preferably in a range of at least 0.3 mm to the half width or length of the edge guard tooth 22. The connection edge 39 may be provided as a non-rounded edge, e.g. as depicted in Fig. 3 or as a rounded edge. Since the connection edge 39 is retracted from the distal end 41 of the edge guard tooth 22 by the distance D, a contact of the connection edge 39 with the skin of a user during haircutting operation could be beneficially prevented.
-
The second edge guard tooth portion 35 comprises a contact surface 43 for contacting skin and hair comprising one or more of a front contact surface 43-2 arranged at least partially at a front of the guard blade 20, an outer contact surface 43-1 arranged at least partially at an outer side of the guard blade 20, and/or an inner contact surface 43-3 facing at least partially an inner side of the guard blade 20, wherein the second surface 27 abuts to one or more of the front contact surface 43-2, the outer contact surface 43-1 and/or the inner contact surface 43-3 at a first contact portion 51 comprising a first rounded edge 53.
-
The contact surface 43 may be accordingly understood as the outermost surface of the edge guard tooth 22 that should only contact the skin during haircutting operation. Accordingly, the contact surface 43 may be suitably formed, e.g. surface treated, to allow a frictionless movement of the skin along the contact surface 43. This further reduces skin irritation during the haircutting operation.
-
In the depicted embodiment, the second edge guard tooth portion 35 comprises a front contact surface 43-2 arranged at least partially at a front of the guard blade 20, an outer contact surface 43-1 arranged at least partially at an outer side of the guard blade 20, and an inner contact surface 43-3 facing at least partially an inner side of the guard blade 20. In other configurations, only one or two of the above noted contact surfaces may be provided.
-
In the embodiment depicted in Fig. 2, the second surface 27 abuts the front contact surface 43-2, the outer contact surface 43-1 and the inner contact surface 43-3 at a first contact portion 51 comprising a first rounded edge 53. In other words, the outermost part of the upper surface of the edge start tooth 22, which is formed by the second surface 27, is connected to respective perpendicular contact surfaces 43 via the first rounded edge 53. Accordingly, skin contacting the connection between the respective contact surfaces 43 and the second surface 27 may only experience a low friction due to the first rounded edge 53. This accordingly reduces irritation of the skin and facilitates a guidance and deflection of the skin along the contact surfaces 43 and the second surface 27.
-
In other configurations, only portions of the connection between the second surface 27 and the front contact surface 43-2, the outer contact surface 43-1 and the inner contact surface 43-3 are provided with the first rounded edge 53.
-
It is noted that, in the depicted embodiment of Fig. 2, the front contact surface 43-2, the outer contact surface 43-1 and the inner contact surface 43-3 extend essentially perpendicular to the second surface 27. However, in different configurations, one or more the front contact surface 43-2, the outer contact surface 43-1 and the inner contact surface 43-3 may be at least partially inclined such that they extend not in a fully perpendicular manner.
-
The outer contact surface 43-1 is essentially the contact surface of the edge guard tooth 22 that is arranged at the outermost width extension direction W of the guard blade 20. The inner contact surface 43-3 is essentially the contact surface of the edge guard tooth 22 that is arranged opposite to the outer contact surface 43-1 and faces towards an inner portion of the edge guard tooth 22 in the width direction W. As is apparent from Fig. 1, this may be the direction at which the inner guard teeth 21 are arranged. Accordingly, the inner contact surface 43-3 may form a part of a cavity 69 together with an adjacent inner guard tooth 21 in which hair to be cut could be captured.
-
The second edge guard tooth portion 35 comprises the front contact surface 43-2 and the inner contact surface 43-3, and the front contact surface 43-2 and the inner contact surface 43-3 abut at a second contact portion 55 comprising a second rounded edge 57.
-
The second rounded edge 57 accordingly extends in the height direction H in the embodiment depicted in Fig. 2. In other configurations, only portions of the connection between the front contact surface 43-2 and the inner contact surface 43-3 are provided with the second rounded edge 57. Thus, skin contacting the connection between the front contact surface 43-2 and the inner contact surface 43-3 may only experience a low friction due to the second rounded edge 57. This accordingly reduces irritation of the skin and facilitates a guidance and deflection of the skin along the respective front contact surface 43-2 and inner contact surface 43-3.
-
The outer contact surface 43 comprises a base contact surface 43-4 oppositely arranged at the edge guard tooth 22 to the first and/or second surface 27 in the height direction H, wherein the base contact surface 43-4 is essentially perpendicular to one or more of the front contact surface 43-2, the outer contact surface 43-1 and/or the inner contact surface 43-3, wherein the base contact surface 43-4 abuts one or more of the front contact surface 43-2, the outer contact surface 43-1 and/or the inner contact surface 43-3 at a third contact portion 61 comprising a third rounded edge 63.
-
Thus, skin contacting the connection between the base contact surface 43-4 and the front contact surface 43-2, the outer contact surface 43-1 or the inner contact surface 43-3 may only experience a low friction due to the third rounded edge 57. This accordingly reduces irritation of the skin and facilitates a guidance and deflection of the skin along the respective contact surfaces 43.
-
In the depicted configuration, the outer contact surface 43 comprises the base contact surface 43-4 oppositely arranged to the first surface 25 and the second surface 27 in the height direction H. Further, the base contact surface 43-4 is essentially perpendicular to the front contact surface 43-2, the outer contact surface 43-1 and the inner contact surface 43-3, wherein the base contact surface 43-4 abuts the front contact surface 43-2, the outer contact surface 43-1 and the inner contact surface 43-3 at a third contact portion 61 comprising a third rounded edge 63. In other configurations, the base contact surface 43-4 may be oppositely arranged only to one of the first surface 25 or the second surface 27. In further configurations, the base contact surface 43-4 may be essentially perpendicular to only one or two of the front contact surface 43-2, the outer contact surface 43-1 and the inner contact surface 43-3. Likewise, in other configurations the base contact surface 43-4 may abut only one or two of the front contact surface 43-2, the outer contact surface 43-1 and the inner contact surface 43-3 at a third contact portion 61 comprising a third rounded edge 63.
-
In other configurations, only portions of the connection between the base contact surface 43-4 and the front contact surface 43-2, the outer contact surface 43-1 or the inner contact surface 43-3 are provided with the third rounded edge 63.
-
One or more of the first rounded edge 53, the second rounded edge 57 and/or the third rounded edge 63 has a rounded edge curvature radius R1 in a range of 0.1 mm to 1 mm, preferably in a range of 0.2 mm to 0.5 mm and more preferably of about 0.25 mm.
-
The edge guard tooth 22 accordingly has a laterally arranged distal end 41 for contacting skin during use of the haircutting device 100. And between the respective contact surfaces 43 rounded edges 53, 63 are provided. In Fig. 3, for instance, the first rounded edge 53-1 of the first contact portion 51 is shown, where the second surface 27 abuts the front contact surface 43-2. Likewise, the third rounded edge 63-3 of the third contact portion 61 is shown, where the base contact surface 43-4 abuts the front contact surface 43-2. Herein, the first rounded edge 53-1 has a rounded edge curvature radius R1-1 and the third rounded edge 63-2 has a rounded edge curvature radius R1-2. In the depicted embodiment, the curvature radius R1-1 of the first rounded edge 53-1 and the curvature radius R1-2 of the third rounded edge 63-2 is the same. However, it will be understood that each of the rounded edge curvature radii described herein could be individually configured and therefore they could also be at least partially different from each other. The provision of rounded edges generally increases the contact surface of the edge guard tooth 22 at the respective portions and accordingly reduces irritations and discomfort of the skin contacting the edges. Furthermore, the skin could be more easily deflected with less friction. However, in different configurations, at least some of the rounded edges are omitted or even no rounded edges are provided at the edge guard tooth 22.
-
In the embodiment of Fig. 2, the second rounded edge 57 is provided along the height direction H. The first rounded edge 53-1 provided at the outer top side of the edge guard tooth 22, the first rounded edge 53-3 provided at the inner top side of the edge guard tooth 22 and the corresponding third rounded edge 63-1 at the outer bottom side of the edge guard tooth 22 and the third rounded edge 63-3 provided at the inner bottom side of the edge guard tooth 22 are provided essentially along the lateral direction L. Finally, the first rounded edge 53-2 provided at the top front side of the edge guard tooth 22 and the corresponding the third rounded edge 63-2 provided at the bottom front side of the edge guard tooth 22 are provided essentially along the width direction W.
-
However, in different configurations, at least some of the rounded edges 53, 57, 63 are omitted or even no rounded edges 53, 57, 63 are provided at the edge guard tooth 22.
-
The edge guard tooth 22 comprises a contact surface transition portion 65 between the front contact surface 43-2 and the outer contact surface 43-1, wherein the contact surface transition portion 65 has a contact surface curvature radius R2 in a range of 0.1 mm to 4 mm, preferably in a range of 1 mm to 3 mm, more preferably about 2.4 mm.
-
Accordingly, since a curved shape is provided, the respective top and bottom edges 53, 63 described above, likewise transition in a curved manner, e.g. from the front side 71 of the edge guard tooth 22 to the outer side 73 of the edge guard tooth 22. That is, the respective curved top and bottom edges 53, 63 accordingly comprise continuously varying portions of extension in the width direction W and in the lateral direction L.
-
Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed disclosure, from the study of the drawings, the disclosure, and the appended claims. In the claims the word "comprising" or "including" does not exclude other elements or steps and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.
LIST OF REFERENCE SIGNS
-
- 1
- spring assembly
- 3
- driving bridge
- 5
- housing
- 7
- bottom side
- 10
- cutter blade
- 11
- cutter tooth
- 13
- cutter tooth contact surface
- 20
- guard blade
- 21
- inner guard tooth
- 22
- edge guard tooth
- 23
- cutter blade running surface
- 25
- first edge guard tooth surface
- 27
- second edge guard tooth surface
- 29
- outer edge guard tooth portion
- 31
- first edge guard tooth portion
- 33
- transition portion
- 34
- transition surface
- 35
- second edge guard tooth portion
- 37
- guard tooth base portion
- 39
- connection edge
- 41
- distal end
- 43
- contact surface
- 43-1
- outer contact surface
- 43-2
- front contact surface
- 43-3
- inner contact surface
- 43-4
- base contact surface
- 51
- first contact portion
- 53
- first rounded edge
- 55
- second contact portion
- 57
- second rounded edge
- 61
- third contact portion
- 63
- third rounded edge
- 65
- contact surface transition portion
- 67
- outer end of the guard blade
- 69
- reception cavity
- 70
- cutter blade movement
- 71
- edge guard tooth front side
- 73
- edge guard tooth outer side
- 75
- edge guard tooth inner side
- 100
- hair cutting device
- L
- lateral direction
- H
- height direction
- H1
- first height
- H2
- second height
- H3
- transition surface height
- W
- width direction
- R1
- rounded edge curvature radius
- R2
- contact surface curvature radius
- D
- distance