Electric beard trimmer

Abstract

The present invention relates to cutting body hair, such as multi-day beard stubble. More particularly, the present invention relates to a cutting device system 3 for an electric shaver and / or trimmer 1, comprising a pair of cooperating cutting elements (4, 5) having two rows of comb-like cutting teeth (6, 7) on opposite edges thereof and at least one area of ​​cutting perforations 8 between the rows of comb-like cutting teeth, the cutting perforations being formed in the skin-contacting or skin-facing surfaces 50 of the cutting elements, the cutting elements being movably supported relative to one another by a support structure 14 providing a pivot axis 21 about which the cooperating cutting elements can pivot to follow the contours of the skin, the pivot axis extending substantially parallel to the longitudinal direction of the rows of comb-like cutting teeth. The pivot axis is eccentrically positioned closer to a first row of teeth than to a second row of teeth, with the first row of teeth forming a leading edge and the second row forming a trailing edge when moving the cutting device system in a general direction of movement that is intuitively preferred by most users.

Description

[Technical field]

[0001] The present invention relates to cutting body hair such as multi-day beard stubble. More particularly, the present invention relates to a cutting device system 3 for an electric razor and / or trimmer having a pair of cooperating cutting elements having two rows of comb-like cutting teeth on opposite edges and at least one area of ​​cutting perforations between the rows of comb-like cutting teeth, the cutting perforations being formed in the skin-contacting or skin-facing surfaces of the cutting elements, the cutting elements being movably supported relative to one another by a support structure providing a pivot axis around which the cooperating cutting elements can pivot to follow the contours of the skin, the pivot axis extending substantially parallel to the longitudinal direction of the rows of comb-like cutting teeth. [Background technology]

[0002] Electric razors and trimmers utilize a variety of mechanisms to provide hair cutting functionality. Some electric razors include a perforated shear foil that cooperates with a lower cutting device movable relative to the shear foil to cut hair that falls into the perforations in the shear foil. Such shear foil type razors are often used on a daily basis to provide a clean shave where short beard stubble is cut just above the skin surface.

[0003] On the other hand, other cutting device systems including a pair of cooperating cutting elements with comb-like edges include one or more rows of comb-like or rake-like cutting teeth that reciprocate or rotate relative to each other and are often used to cut longer beard stubble or problem hairs that are difficult to cut, for example due to growing at a very small angle to the skin or from very elastic skin. The teeth of such comb-like or rake-like cutting elements usually project substantially parallel to each other or substantially radially, depending on the type of drive movement, and are able to cut hairs that fall in the gaps between the cutting teeth, the cutting or shearing being achieved in a scissor-like manner when the cutting teeth of the cooperating elements close the gaps between the finger-like cutting teeth and pass each other.

[0004] Such a cutting device system for longer hair may be integrated into an electric razor or trimmer and may at the same time comprise the above-mentioned shear foil cutting device. For example, the cutting element may include, for example, two rows of comb-like cutting teeth arranged on either side of the cutting element and an area of ​​shear foil-like cutting perforations between the rows of comb-like cutting teeth.

[0005] For example, EP 2425938(B1) shows a razor with a pair of long hair trimmers integrated between shear foil cutting devices. Furthermore, EP 2747958(B1) and Chinese Utility Model 206287174(U) disclose hair trimmers with two rows of cooperating cutting teeth located on either side of the razor head, where the cutting teeth of the upper comb-like cutting element overhang the tips of the lower cutting element and are provided with rounded and thickened tips, thereby preventing the protruding tips from piercing and irritating the skin.

[0006] A similar cutting device system is shown in US Patent Application Publication No. 2017 / 0050326(A1) in which the lower comb cutting element is fixed and the upper comb cutting element is movable.

[0007] Razors and / or trimmers combining rows of comb-like cutting teeth at opposing edges and shear foil-like cutting perforations between the rows of comb-like teeth may include a C-shaped outer cutting element, the edges of which are folded to form inwardly bent limbs like those of a C or U, which are held by a support frame. A transition edge portion connecting the folded limbs with a central portion of the outer cutting element is contoured or configured to form a row of comb-like teeth for cutting longer stubble, while the central portion of the cutting element is provided with at least one area of ​​perforations for cutting short hair. The outer cutting element cooperates with an inner cutting element, which may be plate-shaped, and may include rows of comb-like teeth at opposing edges for cooperation with the comb-like teeth of the outer cutting element, and further at least one area of ​​perforations or other cutouts between the comb-like tooth edges for cooperation with the perforations in the outer cutting element.

[0008] For this reason, shearing foils such as cutting perforations for cutting short hairs and comb-like cutting teeth for cutting longer hairs or stubble may be integrated in the same cutting element, the inner cutting element being normally biased against the outer cutting element by a spring device, which may include a pair of flexible spring arms extending from a central base portion of the support structure towards the inner cutting element. The spring arms may have a kind of V-shaped configuration and may contact the inner cutting element in a section between the central region of the perforations and the opposing tooth-like edge. Due to such biasing of the inner cutting element against the outer cutting element, pulling or plucking of the hairs cut in the perforations may be avoided, but on the other hand, the friction between the cutting elements is rather high, causing high energy consumption by the drive unit and further heating of the cutting elements, which is often perceived as unpleasant or uncomfortable. Such a cutting device system is shown in Chinese Utility Model No. 209478241 (U) and US Patent Application Publication No. 2018 / 0257248 (A1).

[0009] A similar cutting gear system is disclosed by EP 3131716(B1), in which a support structure includes an outer frame holding an outer cutting element on the opposing edge portion of the support structure, such outer frame including a stepped projection on its inner surface forming a shoulder for supporting an inner cutting element at a toothed comb edge. The support structure includes a four-bar linkage that connects the cutting gear system to the handle of the trimmer and allows the cutting element to pivot about a pivot axis parallel to the axis of reciprocation. With a four-bar linkage system, the pivot axis is not a fixed axis, but can move along a path that defines the possible positions of the instantaneous center of rotation. Such four-bar links tend to be flexible and thus can affect the transmission of the drive action to the cutting element through a drive train that bridges the gap between the handle and the cutting gear head.

[0010] Such beard stubble trimmers and razors must address very different and diverse functional requirements and performance issues, such as closeness, thoroughness, good visibility of the cut location, efficiency, and comfortable feel, good ergonomics and handling. Closeness means short or very short remaining stubble, whereas thoroughness means fewer missed hairs, especially in problem areas such as the neck. Efficiency means fewer and faster strokes, sufficient to achieve the desired trimming result. Comfortable feel depends on the individual user, but often includes better glide on the skin with less irritation in the form of cuts or abrasions. Visibility of the cut location is particularly important in the case of styling or contouring edges to achieve hair removal with localized precision.

[0011] Satisfying such various performance issues simultaneously is very difficult, and becomes even more difficult when different types of cutting profiles, such as shear foil-like perforations and comb-like tooth rows, are integrated into the same cutting element, such as C-shaped cutting blades that reciprocate relative to one another, since such multi-function cutting device elements may not be exclusively adapted for one particular cutting function. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] European Patent No. 2425938(B1) [Patent Document 2] European Patent No. 2747958(B1) [Patent Document 3] China Utility Model No. 206287174(U) [Patent Document 4] US Patent Application Publication No. 2017 / 0050326(A1) [Patent Document 5] China Utility Model No. 209478241(U) [Patent Document 6] US Patent Application Publication No. 2018 / 0257248(A1) [Patent Document 7] European Patent No. 3131716(B1) Summary of the Invention [Means for solving the problem]

[0013] The object underlying the present invention is to provide an improved cutting device system, which avoids at least one of the drawbacks of the prior art and / or further develops existing solutions. A more specific object underlying the present invention is to provide a close and thorough cut of hair and longer stubble, including good control of edge contouring, while avoiding skin irritation. A further object is a good adaptation of the cutting device system to the contours of the skin, without risking skin damage due to uncontrolled pivoting of the cutting elements. Another object underlying the present invention is a reliable and clean cutting action of the cooperating cutting teeth and optionally cutting perforations, to avoid plucking and pulling of hair, without sacrificing low friction between the cutting elements, low temperatures of the cutting teeth, and low energy consumption and therefore long energy storage life.

[0014] According to one aspect, the cutting device system may pivot relative to the handle about an eccentric pivot axis that is not symmetrically positioned relative to the opposing comb-like cutting edges for cutting long hairs, such that pivoting the cutting element about the pivot axis results in a larger movement of one of the comb-like cutting edges compared to the other. More specifically, the pivot axis is positioned offset from a central plane that extends perpendicular to a central portion of the skin contacting and / or skin facing surface of the cutting device element, such that the pivot axis is closer to the first of the rows of comb-like cutting teeth than the second of the rows of comb-like cutting teeth. Upon pivoting, the first row of comb-like cutting teeth closer to the pivot axis makes a smaller or shorter lateral movement, while the second row of comb-like cutting teeth further away from the pivot axis makes a larger or larger lateral movement. The lateral movement follows a circular path around the pivot axis, the length of the movement depending on the lever arm or pivot arm, i.e., the distance from the pivot axis. The cutting system further includes a biasing device for biasing the cutting elements toward a home position about a pivot axis, the pivot axis having a fixed position relative to one of the cutting elements and a fixed position relative to the razor / trimmer handle.

[0015] More specifically, the pivot axis may be located near a row of comb-like cutting teeth that is typically used as a leading edge that advances forward when moving the cutting device system along the skin to be shaved. Depending on the particular aspect of the razor and / or trimmer, e.g., the position and / or orientation of the cutting element relative to the handle, and / or the position and orientation of the skin-contacting surface of the cutting element in its home position, and / or the projection of the cutting element to a particular side of the handle, and / or the offset and / or cranking of the cutting device head relative to the longitudinal axis of the handle, and / or the placement of operating keys, such as an on / off key, on the handle that suggest a particular way to grip the handle, the cutting device system may have a common or preferred direction of movement in which the majority of users intuitively move the cutting device system over the skin to be shaved, such that one comb-like cutting edge is a leading edge and the other comb-like cutting edge is a trailing edge, and the cutting device system is moved in the preferred direction of movement of most users.

[0016] By offsetting the pivot axis towards the preferred leading edge of the cutting device system, i.e. towards the row of comb-like cutting teeth that form the leading edge when the cutting device system is moved in the general direction of movement of most users, movement of the leading edge caused by pivoting above the pivot axis in a lateral direction to the skin being shaved is reduced, thus providing greater user comfort and reducing the risk of skin irritation or injury, such as small cuts. Because of such pivoting of the cutting device system, greater lateral movement at the opposite side, i.e. the trailing edge, is insignificant and does not adversely affect comfort or the risk of injury and skin irritation.

[0017] In the home or neutral or initial position of the cutting element relative to the pivot axis, the cutting element may be tilted at an acute angle relative to the longitudinal handle axis such that the skin contacting and / or skin facing surface of the cutting device element faces towards the front side of the shaper / trimmer handle. Considering such tilt towards the front side in the home position of the cutting element, the pivot axis is located near the row of comb teeth located at the front side, while the opposite row of comb teeth located at the rear side of the handle is further away from the pivot axis.

[0018] Because many users shave by pulling the cutting device system along the skin with the front row of teeth forming a leading edge, locating the pivot axis closer to the front row of teeth can improve user comfort and reduce the risk of skin damage, such as skin irritation or cuts, that can be caused by the cutting teeth pivoting against the skin or pitching too sharply toward the skin.

[0019] These and other advantages will become apparent from the following description which refers to drawings and possible examples. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a perspective view of an electric beard trimmer / razor including a cutting system having a pair of cooperating comb-like cutting elements that reciprocate relative to one another, where partial view (a) shows the front side of the electric beard trimmer and partial view (b) shows the beard trimmer working on the chin; [Diagram 2] FIG. 2 is a cross-sectional view of a beard trimmer / razor showing cooperating comb cutting elements and a drive system for driving the cutting elements. [Diagram 3] FIG. 1 is a perspective view of a cutting device system including a pair of cooperating comb cutting elements and a support structure for supporting the cutting elements relative to one another. [Figure 4]FIG. 1 shows a cross-sectional view of the cutting device system and support structure, where the C-shaped outer cutting element is shown bent or curved around the outer frame portion and the inner cutting element is shown supported by a V-shaped inner support frame forming a rigid support rib that extends at a steep angle from the base portion of the support structure to the outer frame portion, partial view (a) showing the rigid support rib while view (b) shows the flexible spring-like support rib. [Diagram 5] FIG. 1 is an exploded perspective view of elements of a cutting apparatus system including outer and inner cutting elements, an outer support frame for holding the outer cutting elements, a chute- or trough-shaped inner support frame including rigid support ribs for supporting the inner cutting elements, a drive element for reciprocating the inner cutting elements, and a guide block for guiding the reciprocating drive element. [Figure 6] FIG. 13 is a side view showing pivoting of the cutting device system relative to the razor / trimmer handle permitted by the support structure. [Figure 7] FIG. 13 is a side view showing the cutting device system pivoting about its pivot axis following skin contouring. [Figure 8] FIG. 13 is a plan view of an outer cutting element showing distinct areas of perforation in the cutting element. [Figure 9] A cross-sectional view of a perforation having a conical or non-cylindrical profile that expands toward the skin contact surface to help hair enter the perforation, with a left side view (small and enlarged) of a flat cutting element and a right side view (small and enlarged) of a dome / convex curved shaped cutting element. [Figure 10] FIG. 13 is an exploded perspective view of a pivot bearing structure that provides a pivot axis for the cutting element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] To allow for a more comfortable shaving and / or trimming due to self-adaptation of the cutting device blade to the contours of the skin while reducing the risk of skin irritation or even damage, an improved pivoting support structure has been suggested to reduce lateral movement of the leading cutting edge to the skin due to pivoting of the cutting element as the cutting device system is moved along the skin to be shaved and the pitch angle of the cutting device system is adapted to the contours of the skin.

[0022] More specifically, it is suggested that the cutting device system may pivot relative to the trimmer / razor handle about an eccentric pivot axis that is not symmetrically positioned relative to the opposing comb-like cutting edges to cut long hairs, such that pivoting the cutting element about the pivot axis results in a smaller movement of one of the comb-like cutting edges compared to the other. More specifically, the pivot axis is positioned offset from a central plane that extends perpendicular to a central portion of the skin-contacting and / or skin-facing surface of the cutting device element, such that the pivot axis is closer to the first of the rows of comb-like cutting teeth than the second of the rows of comb-like cutting teeth. When pivoting, the first row of comb-like cutting teeth closer to the pivot axis makes a shorter lateral movement, while the second row of comb-like cutting teeth further away from the pivot axis makes a longer lateral movement, such lateral movement following a circular path around the pivot axis, the length of the movement depending on the distance of the row of teeth from the pivot axis.

[0023] More specifically, the pivot axis may be located near a row of comb-like cutting teeth that are typically used as the leading edge that advances forward when moving the cutting device system along the skin to be shaved. Depending on the particular aspect of the razor and / or trimmer, e.g., the location and / or orientation of the cutting element, or its skin-contacting surface in its home position, and / or the projection of the cutting element to a particular side of the handle, and / or the offset and / or cranking of the cutting device head relative to the longitudinal axis of the handle, and / or the placement of operating keys such as on / off keys that suggest a particular way to grip the handle, the cutting device system may have a general or preferred direction of movement in which the majority of users will intuitively move the cutting device system over the skin to be shaved, whereby one comb-like cutting edge is a leading edge and the other comb-like cutting edge is a trailing edge, and the cutting device system is moved in the general direction of movement that is intuitively preferred for most users.

[0024] By offsetting the pivot axis towards the preferred leading edge of the cutting device system, i.e. towards the row of comb-like cutting teeth that form the leading edge when the cutting device system is moved in the general direction of movement of most users, movement of the leading edge caused by pivoting above the pivot axis in a lateral direction relative to the skin being shaved is reduced, thus providing greater user comfort and reducing the risk of skin irritation or injury, such as minor cuts. Greater lateral movement of the trailing edge caused by such pivoting of the cutting device system is insignificant and does not adversely affect comfort or the risk of injury and skin irritation.

[0025] In the home or neutral or initial position of the cutting element relative to the pivot axis, the cutting element may be tilted at an acute angle relative to the longitudinal handle axis such that the skin contacting and / or skin facing surface of the cutting device element faces towards the front side of the shaper / trimmer handle. Given such a forward tilt in the home position of the cutting element, the pivot axis is located near the row of comb teeth located at the front side, while the opposite row of comb teeth located at the rear side of the handle is further away from the pivot axis. Since many users shave by pulling the cutting device system along the skin with the front row of comb teeth forming a leading edge, locating the pivot axis closer to the front row of comb teeth can improve user comfort and reduce the risk of skin damage, such as skin irritation or cuts, that may occur due to the comb teeth pivoting to the skin or pitching too sharply towards the skin.

[0026] Essentially, if the pivot axis is located directly on the leading cutting edge, lateral movement of the leading cutting edge can be completely eliminated since there is no leverage arm or pivot radius with respect to distance from the pivot axis. Thus, depending on the aggressiveness of the comb teeth and the desired level of comfort, it may be desirable to locate the pivot axis relatively close to the leading edge. For example, the pivot axis can be located between the row of comb teeth and the area of ​​perforations formed in the skin-contacting surface.

[0027] However, offsetting the pivot axis too far from the center of the cutting device system can compromise comfort and safety when moving the cutting device system in an opposite or undesired direction of movement over the skin to be shaved. To achieve a good compromise, the pivot axis can be spaced from the first row of tines by a distance that is about 60%-90%, or 70%-90%, or 75%-85% of the distance between the pivot axis and the opposing second row of tines.

[0028] Thus, the pivot axis may be located approximately 10-40% closer to one row of teeth comb than to the other row of teeth comb.

[0029] To achieve good responsiveness of the pivoting of the cutting element, and therefore good conformity to the skin contours of different users who may apply different levels of skin contact pressure, the pivot axis may be located close to the skin contact surface to reduce the pivoting effect of torque and thereby friction: when the cutting device system is pressed against the skin and moved along the skin, friction caused between the skin contact surface and the skin being shaved will tend or attempt to pivot the cutting device system about the pivot axis, and the leverage arm of such frictional force will be smaller the closer the pivot axis is to the skin contact surface.

[0030] More specifically, the pivot axis may be located slightly below the skin contact surface and / or within the cutting device head chamber surrounded by the opposing edge of one of the cutting elements and the frame part of the support structure holding said cutting element. Such a location significantly reduces on the one hand the effect of frictional forces on the pivot axis and therefore the pivot torque caused by such frictional forces, and on the other hand allows a compact and space-saving arrangement of the support structure.

[0031] To allow for easy and intuitive use of the razor / trimmer, the support structure may be configured to provide a pivot range for the cutting elements that is asymmetric with respect to the longitudinal handle axis. In other words, the pivot range may be greater toward one side of the handle than toward the opposite side of the handle. More specifically, the pivot range may be configured such that the skin-contacting and / or skin-facing surfaces of the cutting elements face toward the same side of the handle over at least 2 / 3 or 3 / 4 of the pivot range.

[0032] A natural razor feel and easy intuitive use can be achieved when the pivot range allows for various pivot positions of the cutting element with tilt angles ranging from -20° to 60° or 0° to 40° ±10° or -5°, the tilt angles being defined between an imaginary plane extending perpendicular to the longitudinal handle axis and another imaginary plane tangent to the skin-contacting / facing surface of the cutting element.

[0033] A biasing device may be associated with the pivot axis to bias the cutting element to a particular home position. Such a biasing device may be configured to bias the cutting element about the pivot axis toward an end of a limited pivot range. In other words, the biasing device, which may include a spring device, does not bias the cutting element to a neutral center position from which it can pivot in opposite directions, but rather the biasing device attempts to bias the cutting element to an extreme or end pivot position from which it can pivot in only one direction.

[0034] More specifically, the biasing device may be configured to bias the cutting element to an angular pivot position with the smallest possible angle of inclination of the skin-contacting surface relative to the longitudinal handle axis such that as the cutting element pivots from its biased home position, the plane tangent to the skin-contacting surface will tend to be more transverse to the longitudinal handle axis and / or approach a position perpendicular to the longitudinal handle axis.

[0035] Due to this biased home position, where the skin contact surface is inclined at a fairly small angle to the longitudinal handle axis, the user intuitively pulls the cutter system so that the first row of cutting teeth described above advances over the skin to be shaved. The eccentric or offset pivot axis thus allows fine adaptation of the cutting element to the skin contours and avoids uncontrolled lateral movements that potentially pose a risk of skin irritation.

[0036] Regardless of the preferred direction in which the cutting device system is moved, biasing the cutting element to its home position at the end of the pivot range can also reduce the risk of skin irritation or even skin damage when the cutting device system moves over the skin to shave in the unpreferred opposite direction, i.e. when the second row of comb-like cutting teeth is at the leading edge, as the second row of comb-like cutting teeth can flex quite easily upon pivoting and give way to the skin, and only a very low skin contact force is required at the opposite edge because the distance to the pivot axis is quite large and therefore the impact of such skin contact force at the opposite edge is large.

[0037] To avoid excessive flexibility that is detrimental to the efficient transmission of drive force and / or torque to the cutting elements, the pivot axis may have a fixed location relative to the non-reciprocating cutting elements and / or a fixed location relative to the razor / trimmer handle. Such a fixed pivot axis location makes it possible to avoid yielding and giant joint linkages.

[0038] The support structure may include a rigid pivot shaft holder having a mounting portion for fixedly mounting the pivot shaft holder to a handle or chassis portion of a razor / trimmer, and the pivot shaft holder may include two frame portions extending into or towards a cutting device head chamber defined by the cutting elements and an outer frame portion of the support structure 14 that holds opposing edges of one of the cutting elements.

[0039] More specifically, the pivot holder may include a U-shaped or V-shaped retaining frame element made from metal.

[0040] To achieve a smooth and comfortable cutting action, it serves to avoid the cutting elements and thus the cooperating comb teeth and / or the cooperating cutting perforations separating from one another in order to avoid hairs not being properly cut any more or being further gripped between the teeth or cutting perforations moving relative to one another. Essentially, this can be prevented by pressing the cooperating cutting elements against one another, for example by means of a spring device such as a flexible support rib which biases the teeth / perforations of one cutting element against the teeth / perforations of the other cutting element.

[0041] Instead of or in addition to such flexible support ribs, one of the cutting elements may be clamped between the other cutting element and a support element or support structure, such as a support frame, which may include a rigid rib or web-like flange that precisely and rigidly supports and guides the inner cutting element in a predetermined position and sufficiently close to the outer cutting element, the rigid support rib and the outer cutting element defining a gap in which the clamped cutting element is slidably and / or movably received, the gap may be slightly thicker than the clamped cutting element to provide some play at least during non-use to reduce friction and heat generation. When the outer cutting element is pressed against or at least contacts the skin during operation of the razor / trimmer, the outer cutting element may deflect and then fit closely over at least the inner cutting element. The clamped cutting element may move relative to the outer cutting element without friction or with very low friction, but deflection is nevertheless prevented even when the thickness of the clamped cutting element is very small.

[0042] More specifically, one of the cutting elements may be sandwiched between the other cutting element and said flexible or rigid support rib or web-like flange, which may include a rigid rib or web-like flange that precisely and firmly supports and guides the inner cutting element at a predetermined position under and sufficiently close to the outer cutting element, said rigid or flexible support rib and outer cutting element defining a gap in which the sandwiched cutting element is slidably and / or movably received, said gap being slightly thicker than the sandwiched cutting element to provide some play at least during non-use to reduce friction and heat generation when said rib is rigid. When the outer cutting element is pressed against or at least contacts the skin during operation of the razor / trimmer, it may deflect and then fit closely over at least the inner cutting element. If a flexible rib is used, said gap may be zero or at least less than said blade thickness to provide some bias without containing the blade therein. The clamped cutting element can move relative to the outer cutting element without or with very low friction, yet is prevented from deflecting even when the thickness of the clamped cutting element is very small.

[0043] To achieve low friction and at the same time avoid gripping of hair between the cutting teeth, the gap from the tip portion of the support rib to the outer cutting element may have a thickness greater than the thickness of the cutting element that is clamped only by an amount less than the thickness of the hair to be cut.

[0044] More specifically, the amount by which the width of the gap exceeds the thickness of the clamped cutting element may be less than 40 μm. For example, the amount may be in the range of 20 μm to 40 μm. Such an arrangement is a good compromise between ease of manufacture and a sufficiently small risk of plucking or pulling the hairs being cut.

[0045] The skin-contacting / facing surface defined by the outer cutting element may be substantially planar or flat. Alternatively, the skin-contacting surface defined by the outer cutting element may be slightly convex or slightly dome-shaped when viewed in a cross section taken perpendicular to the reciprocating direction. In a cross-sectional plan view parallel to the reciprocating axis, the skin-contacting surface may be linear. Thus, the skin-contacting surface may be slightly smoothly convex with a shallow chute-like or trough-like shape.

[0046] Both the outer cutting element and the inner cutting element may have such a shape that corresponds to the skin contacting surface.

[0047] To keep the inner and outer cutting elements snugly fitted together in the area where the cutting perforations are made, it may be helpful if a rigid or flexible support rib having a support edge extends directly adjacent or closely adjacent to the outer boundary of the area of ​​perforations. The support rib may have a support edge and be in direct contact with the inner cutting element along the outermost row of perforations.

[0048] Alternatively, the support edge of the support rib may contact the inner cutting element along a line spaced from the outermost row of perforations. Nevertheless, the support edge of the support rib may be positioned on the opposite edge of the cutting element near the outermost row of perforations and then near the cutting teeth. More specifically, the distance of the support edge of the support rib from the area of ​​the perforations may be less than 1 / 3 or less than 1 / 4 of the distance of the support edge from the comb-like cutting teeth.

[0049] To balance the skin contact pressure induced on the inner cutting element via the outer cutting element, the support edges of the support ribs facing the inner cutting element may be spaced apart from each other by a distance ranging from 35% to 70% or 40% to 60% of the distance defined between the rows of comb teeth at the opposing edges of the cutting elements. Depending on the user's preference, different portions of the skin contact surface defined by the outer cutting element may be pressed against the skin with varying forces so that varying skin pressures may result. To balance such varying pressures, considering the cross-sectional view of the inner cutting element, it is helpful when the inner cutting element is supported by said rigid support ribs at about 1 / 3 to about 2 / 3 of the span width of the inner cutting element.

[0050] The support ribs and / or their support edges which contact the inner cutting element may extend parallel to the axis of reciprocation and / or parallel to the rows of comb teeth on opposing edges of the cutting element.

[0051] The support ribs may be secured to the base portion of the support structure in different ways. For example, the support ribs may be welded to the base portion or embedded within the material of the base portion. For example, when separate support ribs are present, each rib may be inserted into a slot-like recess in the base portion to hold the support rib in a desired orientation and position.

[0052] Alternatively, the support ribs may be inclined toward each other at an acute angle and may be integrally connected to each other and / or may form an integral part of the support rib element. More specifically, the support ribs may be formed by V-shaped or broken limbs of a support frame insert that may be inserted into a support structure supporting the cutting element and / or attached to a base portion of such support structure. Such a support rib insert may have a chute-like or trough-like configuration including a strip-like bottom portion from which two support ribs extend at the described inclination. Such a chute-like insert may be inserted into a support structure and fixedly attached to the base portion of the support structure. For example, the bottom portion of the insert may be seated on an inner surface of the bottom portion of the outer support frame at a central portion of the insert, and the central bottom portion of the outer support frame may form a seat for the support rib insert. Seating the support rib insert on the bottom portion of the outer support frame may take up the support force and pressure induced in the support rib, thereby pressing the support rib insert onto the bottom portion of the outer support frame.

[0053] The inner support frame insert may be fixedly attached to the outer support frame, for example by being glued and / or welded and / or fitted to the outer support frame.

[0054] The outer support frame part holding the outer cutting element together with the outer cutting element on its opposing edge parts may define a cutting device head chamber which may be configured tubular or barrel-like with open or closed end faces, the axial end faces of which may be open to allow the discharge of hair waste or cut stubble from such cutting device head chamber.

[0055] More specifically, such a cutting device head chamber defined by the outer frame portion and the outer cutting element may be divided into a plurality of subchambers by the aforementioned support ribs of the inner support frame. More specifically, the cutting device head chamber may be divided by the rigid support ribs into an inner subchamber for collecting short hair particles from the cutting holes and a pair of outer subchambers for collecting long hair particles cut by the comb-like cutting teeth.

[0056] The hair waste collected in the inner subchamber and coming from the perforations, as well as the cut stubble collected in the outer subchamber, may be discharged from the respective subchambers via at least one open end face, both ends of each of said subchambers may be open to enhance cleaning of said subchambers and discharge of the collected hair waste therefrom.

[0057] The clamped cutting elements may be driven by a drive connected to the inner cutting elements and coupled to a drive train that transmits the drive motion of the drive unit, and the inner support frame, including a rigid support rib and an outer support frame, includes an outer frame portion that holds the outer cutting elements and a base portion that supports the inner support frame, and may include one or more central, elongated or slit-like through-holes in which the drive and / or a portion of the drive train are slidably received. In other words, the drive and / or drive train extend through and are slidably received in the through-holes in the inner and outer support frames to allow reciprocating movement of the drive and thus the clamped cutting elements relative to the other cutting elements.

[0058] The drivers may include elongated rod-like portions attached to opposing end portions of the inner cutting element and housed within an inner subchamber defined between the rigid support rib and the inner cutting element.

[0059] The clamped cutting element may be a driven cutting element that may reciprocate or rotate, depending on the type of drive.

[0060] Basically, each of the cooperating cutting elements may be driven. However, in order to combine an easy drive system with a safe and soft cutting action, the upper or outer cutting element having the skin contact surface may be standing and / or non-reciprocating and non-rotating, while the lower or inner cutting element, which may be the clamped cutting element, may reciprocate or oscillate in rotation.

[0061] As can be seen from Figures 1 and 2, the cutting device system 3 may be part of a cutting device head 2 that may be attached to a handle 100 of a razor and / or trimmer 1. More specifically, the razor and / or trimmer 1 may include an elongated handle 100 housing a battery 104, a control unit 111, electronic and / or electrical components such as an electric drive motor 103 or a magnetic drive motor, and a drive train 109 for transmitting drive motion of the motor to the cutting device system in the cutting device head 2, and referring to Figure 2, the cutting device head 2 may be located at one end of the elongated handle 100.

[0062] The cutter system 3, including a pair of cooperating cutting elements 4 and 5, may be the only cutter system of the cutter head 2, as is the case in the embodiment shown in Figure 1. On the other hand, the cutter system 3 may be incorporated into a razor head 2 having other cutter systems, such as shear foil cutters, e.g., the cutter system 3, including at least one row of cooperating cutting teeth 6, 7, may be positioned between a pair of shear foil cutters or, alternatively, may be positioned in front of such shear foil cutters.

[0063] As shown in FIG. 1, the cutter system 3 may include elongated rows of cutting teeth 6 and 7 that can reciprocate relative to one another along a linear path to close the gaps between the teeth and provide a cutting action by passing over one another. On the other hand, the cutter system 3 may also include cutting teeth 6 and 7 aligned along a circle and / or arranged radially. Such rotating cutting elements 4 and 5 may have cutting teeth 6 and 7 that project substantially radially, and the cutting elements 4 and 5 may be driven to rotate relative to one another and / or to rotationally oscillate relative to one another. The cutting action is essentially similar to the reciprocating cutting elements as radially extending teeth, which when rotating and / or rotationally oscillating, periodically close and reopen the gaps between adjacent teeth and pass over each other like scissors.

[0064] As shown in FIG. 2, the drive system may include a motor, the shaft of which can rotate an eccentric drive pin received between a channel-like profile of the driver 18, the eccentric drive pin being connected to one of the cutting elements 4 and providing a reciprocating motion due to engagement of the rotating eccentric drive pin with the profile of the driver 18.

[0065] As shown by Figures 3, 4 and 5, the cooperating cutting elements 4 and 5 may have an essentially, at least approximately, plate-shaped configuration, with each cutting element 4 and 5 including two rows of cutting teeth 6 and 7 which, with reference to Figures 4 and 5, may be located on opposite longitudinal sides of the plate-shaped cutting elements 4 and 5. The cutting elements 4 and 5 are supported and positioned such that the flat sides of the cutting elements lie on top of each other. More specifically, the cutting teeth 6 and 7 of the cutting elements 4 and 5 abut each other back to back, like the blades of a pair of scissors.

[0066] In addition to such comb-like cutting teeth 6 and 7, the cooperating cutting elements 4 and 5 may comprise at least one region of cutting perforations located between the rows of cutting teeth 6 and 7 at an intermediate portion of the cutting elements 4 and 5. More specifically, the outer cutting element 4 defining the skin contact surface of the cutter system 3 may include at least two rows of perforations 8, which may be formed as small sized through holes having a circular, oval, elliptical or polygonal shape.

[0067] Specifically, such small-sized through holes forming the perforations 8 may have a hexagonal shape, and the long axis of such a hexagonal through hole, i.e., the axis passing through the opposing corners of the hexagonal shape, may be oriented transversely to the reciprocating axis 10 of the cutting elements 4 and 5.

[0068] As can be seen in figure 9, the perforations 8 may expand towards the skin contact / skin facing surface, i.e. the cross-sectional area of ​​the perforations 8 is larger towards the skin contact surface. Such a trompet-like or conical or truncated pyramidal shape helps the hair to enter the perforations, as can be seen in figure 9.

[0069] As can be seen from Fig. 8, the perforations 8 may not be distributed at all over a central section of the skin contact surface, but are located only in a limited area. More specifically, the cutting perforations 8 for cutting short hairs may be limited to an area 70, 90 of the skin facing or skin-facing surface 50 of the cutting element 4 following the comb-like cutting teeth 6, 7 as the cutting device system 3 moves along the skin to be shaved with one of the forward moving rows of comb-like teeth 6, 7, while an intermediate portion 80 of the skin facing / skin-facing surface defined by the cutting element between said opposing rows of comb-like teeth may be non-perforated.

[0070] Such an arrangement of the limited area 70, 90 of the spaced apart perforations 8 allows for very short hairs to be cut by the perforations 8 that immediately follow one of the preceding rake-like cutting edges, while perforations further away from the preceding comb-like cutting edge are less effective in cutting very short hairs. Due to the elimination of perforations in areas of the skin contact surface 50 that are less effective in cutting very short hairs, friction between the cutting elements 4, 5 is reduced without sacrificing efficiency in cutting very short hairs. Friction is reduced due to fewer cutting edges with fewer perforations that need to pass each other as the cutting elements move relative to each other, so that already cut hair particles or hair debris exiting the cutting perforations moving forward across the skin to be shaved are not cut or ground again, reducing friction losses.

[0071] More specifically, the cutting perforations 8 may be arranged in two separated elongated regions 70, 90 of perforations separated from each other by an elongated unperforated central section 80 on the outer side of the cutting element 4 that defines the skin contact surface 50, each of which includes at least two rows of perforations 8 extending along and / or parallel to the rows of the comb-like cutting teeth 6, 7.

[0072] To allow sufficient support of the cutting elements moving relative to one another without interfering with the cutting action of the comb teeth 6, 7 and perforations 8, the perforated areas 70, 90 may also be separated or spaced from the row of comb teeth 6, 7 by elongated, unperforated side sections 61, 62 of the outer cutting element, and the support structure may include a pair of flexible or rigid support ribs 19 adjacent or along the outer boundary of the perforated areas 70, 90 to support the inside of the cutting element 5 below the unperforated side sections 61, 62.

[0073] To reduce friction resulting from engagement between the support structure 14 and the moving cutting element 5, the inner cutting element 5 may extend unsupported below the unperforated central section 80 between the regions 70, 90 of perforations 8.

[0074] The elongated unperforated central section 80 of the skin-contacting surface 50 defined by the outer cutting elements may have a size or width that is greater than a size or width of each of the regions of perforation 70, 90. More specifically, the unperforated central section of the skin-contacting surface may extend over an area in the range of 100%-250% or 110%-175% of the area defined by each region of perforation, with reference to FIG.

[0075] More generally, more than 2 / 3 or more than 3 / 4 of the area of ​​the skin contacting surface 50 of the cutting device element 4 between the comb-like cutting teeth may be non-perforated. In other words, only 1 / 4 to 2 / 3 of the skin contacting surface 50 between the opposing rake-like tooth edges of the cutting device system 3 may be perforated, as shown in Figure 8. Such a limitation of the area of ​​perforations 8 may significantly reduce friction when the cutting elements 4, 5 move relative to each other.

[0076] Such perforations 8 of the outer cutting device element 4 can cooperate with perforations 9 in the inner cutting element 5 when the cutting elements 4 and 5 reciprocate relative to each other along the reciprocation axis 10. Said perforations 9 of the inner cutting element 5 can also be formed as small-sized through-holes of a shape corresponding to or different from the shape of the perforations 8 of the outer cutting element 4. However, as can be seen from FIG. 5, the perforations 9 in the inner cutting element 5 do not have to be small-sized through-holes but can be larger-sized notches each cooperating with two or more perforations 8 in the other cutting element 4. More specifically, the perforations 9 in the inner cutting element 5 can be formed as longitudinal slot-like notches extending transversely to the reciprocation axis 10 in the longitudinal axis. Thus, each elongated transverse perforation 9 in the inner cutting element 5 can cooperate with a respective row of perforations in the outer cutting element 4.

[0077] The notches in the inner cutting element 5 overlap the perforations 8 in the outer cutting element 4 and, in response to a reciprocating motion, close the perforations 8, resulting in a shearing action and / or cutting of hair introduced into the perforations 8 and 9.

[0078] To support the cutting elements 4 and 5 in the aforementioned position, lying and / or seated back to back against each other but still allowing the cutting teeth 6 and 7 and the perforations 8 and 9 to move back and forth relative to each other, the inner cutting element 5 is clamped between the outer cutting element 4 and a support structure 14, which includes an inner frame that supports the inner cutting element 5 and an outer frame 12 that holds the outer cutting element 4.

[0079] More specifically, the support structure 14 can define a gap 16 within which the inner cutting element 5 can move relative to the outer cutting element 4 , the inner cutting element 5 being slidably guided within the gap 16 .

[0080] More specifically, as can be seen in Figures 4 and 5, the outer cutting element 4 may have a substantially C-shaped configuration when viewed in cross section, with edge portions 4a and 4b that bend or curve away from the skin-contacting surface to form retention flanges attached or fixed to the outer frame portion 12 of the support structure 14. As can be seen in Figure 4, the edge portions 4a and 4b may then be folded or bent around edge portions of the outer frame 12. However, it would alternatively be possible for the retention flanges 4a and 4b of the cutting element 4 to rest on the inside of the outer frame 12.

[0081] The cutting element 4 may be rigidly or fixedly fastened to the outer frame portion 12. For example, the cutting element 4 may be welded or glued to the outer frame 12.

[0082] 4 and 5, the outer frame portion 12 of the support structure 14 may include a pair of bifurcated legs forming a shallow chute or trough, and the edge portions of the support legs of the outer frame 12 may be provided with slot-like notches 13 forming tooth-like edges that essentially correspond to the cutting teeth 6 and 7 of the cutting elements 4 and 5. More specifically, the notches 13 at the edges of the outer frame 12 allow the hair to be cut to enter the teeth 6 and 7 of the cutting elements 4 and 5, while at the same time providing some support to the cutting teeth 6 of the outer cutting element 4.

[0083] The cutting teeth 6 of the outer cutting element 4 may be formed in a transition area between the folded back support flanges 4 a and 4 b and the front side of the cutting element 4 that defines the skin contact surface of the cutter system 3 .

[0084] The outer cutting elements 4 may form C-shaped plate-like cutting elements whose edges are folded to form inwardly bent limbs like those of a C or U, such folded limbs 4a and 4b being held by the outer support frame portion 12. The transition edge portion connecting the folded limbs with the central portion of the outer cutting element is contoured or configured to form a row of comb teeth 6 for cutting longer stubble, while the central portion 4c of the cutting element 4 provides an area of ​​perforations 8 for cutting shorter hairs.

[0085] As can be seen in FIG. 4, the outer cutting element 4 together with the outer frame 12 of the support structure 14 defines a chamber 17 enclosed by the outer cutting element 4 and the outer frame 12 .

[0086] Located within such chamber 17 is an inner frame 11 for supporting the inner cutting element 5. The inner frame 11 includes at least a pair of rigid support ribs 19 extending from a base section 20 of the support structure 14 towards the inner cutting element 5 lying back-to-back on the outer cutting element 4.

[0087] More specifically, as can be seen in Fig. 4, the rigid support ribs 19 originate from a central section of the outer frame 12 where the branched support legs of the outer frame 12 join together. The support ribs 19 of the inner frame 11 extend from the base section 20 towards the inner cutting elements 5 at an angle β that is significantly steeper than the angle φ between the outer frames 12. As can be seen in Fig. 4, the support ribs 19 of the inner frame 11 may define an angle β between each other of 2x20° to 2x40° or 2x25° to 2x30°, and the rigid support ribs 19 may be symmetrically arranged with respect to a central plane that is perpendicular to the skin contact surface and parallel to the reciprocating axis 10.

[0088] To provide the rigid support ribs 19 with sufficient stiffness, the ribs 19 may have a straight longitudinal axis when viewed in cross section as shown in Figure 4. In other words, the inner and outer surfaces of the support ribs 19 may be planar and flat to achieve buckling stiffness. The support ribs 19 may define a V-shaped configuration originating from the base portion 20.

[0089] Alternatively, the ribs 19 may be flexible and / or resiliently configured to bias the cutting elements 5 inwardly towards the outer cutting elements 4, as shown in Figure 4b. For example, the ribs 19 may have a curved profile that bends when viewed in cross section, referring to Figure 4b, to resiliently bias the cutting elements 5 against the other cutting elements 4.

[0090] 5, the support ribs 19 may be part of the support inserts and / or may be integrally formed with one another. More specifically, the inner frame 11 may have a chute-like or trough-like configuration including a strip-like bottom portion from the edges from which the pair of support ribs 19 extend. For example, the inner frame 11 including the support ribs 19 may be formed from a substantially rectangular metal plate, and the strip-like edges may be bent relative to a middle section to form the angled support ribs 19.

[0091] The inner frame 11 may form an insert that can be inserted into a chamber 17 defined by the outer frame 12 and the outer cutting element 4. More specifically, the insert forming the inner frame 11 may be seated on a base section 20 of the outer frame 12, which absorbs forces and pressures induced on the inner frame 11 when the cutting device system 3 is pressed against the skin to be shaved.

[0092] The inner frame 11 is configured such that the aforementioned gap 16 is defined between the support edge of the rigid support rib 19 on the one hand and the inner side of the outer cutting element 4 on the other hand. More specifically, the height of the support rib 19 is configured such that the gap 16 between the support edge of the rib 19 and the outer cutting element 4 substantially corresponds to the thickness of the inner cutting element 5, said gap 16 may be configured to be slightly wider than the thickness of the plate-like cutting element 5 so as to reduce friction and provide some play between the inner cutting element 5 and the support rib 19 and between the inner cutting element 5 and the outer cutting element 4. Such play may be provided when the cutting device system 3 is unloaded, i.e. not pressed against the skin to be shaved. In the operating state, such play is eliminated when the outer cutting element 4 is pressed against the skin to be shaved and the cutting elements 4 and 5 fit snugly together to achieve a smooth cut of the hair.

[0093] Notwithstanding any such possible play provided by the support structure 14, the support ribs 19 are configured such that the gap 16 exceeds in its width the thickness of the inner cutting element 4 by an amount that is less than the thickness of the hair to be cut. For example, the width of the gap 16 may be greater than the thickness of the clamped cutting element 5 by an amount less than 40 μm or by an amount in the range of 20 μm to 40 μm.

[0094] As can be seen in Figure 4, the inner and outer cutting elements 4 and 5 may have a slightly convex profile. More specifically, the skin-contacting surface defined by the outer cutting element 4 may have a slightly convex, substantially chute-like configuration. When viewed in a cross section taken perpendicular to the reciprocating axis 10, the outer surface of the outer cutting element 4 may be slightly dome-shaped, see Figure 4.

[0095] The inner cutting element 5 substantially corresponds to the shape of the outer cutting element 4 with respect to its slightly convex chute-like shape.

[0096] As can be seen from Fig. 4, the support edges of the support ribs 19 facing the inner cutting element 5 may be spaced apart from each other at a distance ranging from about 35% to 70% or 40% to 60% of the distance defined between the rows of comb teeth 6 and 7 at the opposite edges of the outer cutting element 4. Thus, the rigid support ribs 19 may support the inner cutting element 4 at about 1 / 3 and about 2 / 3 of its span width when viewed in a cross section perpendicular to the reciprocation axis 10. More specifically, the support edges of said ribs 19 may extend directly adjacent to the outer boundary of the area of ​​the perforations 8, and the support ribs 19 may contact the inner cutting element 5 along the outer longitudinal contour of the cutouts forming the perforations 9 in the inner cutting device element 5.

[0097] Due to the configuration of the support ribs 19 extending from the base portion 20 of the support structure 14 at a steeper angle than the support legs of the outer frame 12, the chamber 17 defined by the outer frame 12 and the outer cutting element 4 attached to the outer frame 12 is divided by the support ribs 19 into an inner subchamber 17i and a pair of outer subchambers 17o, referring to Figure 4, which may together have a volume substantially corresponding to the volume of the inner subchamber 17i.

[0098] The rigid support ribs 19 of the inner frame 11 may extend substantially parallel to the reciprocation axis 10. More specifically, the support edges of the ribs 19 that contact the inner cutting element 5 may extend parallel to the reciprocation axis 10.

[0099] As can be seen from Figures 6 and 7, the cutting device head 2 including the cutting device system 3 may be pivotally supported relative to the handle of the razor / trimmer 1 about a pivot axis 21 which may extend substantially parallel to the reciprocation axis 10.

[0100] Said pivot axis 21 may be located close to the cutting elements 4 and 5 and / or within the chamber 17 enclosed by the outer cutting element 4 and the outer frame 12. As can be seen from Figures 5 and 6, the outer frame 12 of the support structure 14 holding the outer cutting element 4 may include a pair of pivot support sections 12a and 12b, which may be spaced apart from each other and / or positioned at opposite end faces of the outer frame 12. On the other hand, a pair of support flanges may be provided on the cutter head side of the handle 100, which may be rotatably connected to said pivot support sections 12a and 12b of the outer frame 12 to form the pivot axis 21.

[0101] More specifically, to avoid excessive flexibility that is detrimental to the efficient transmission of drive force and / or torque to the cutting elements, the pivot axis 21 may have a fixed location relative to the non-reciprocating cutting elements 4 and / or a fixed location relative to the handle 100 of the razor / trimmer 1. Such a fixed pivot axis location makes it possible to avoid yielding and giant joint linkages.

[0102] The support structure 14 may include a rigid pivot shaft holder 41 having a mounting portion 44 for fixedly mounting the pivot shaft holder 41 to the handle 100 or chassis portion 101 of the razor / trimmer 1, and the pivot shaft holder 41 may include two frame portions 42 extending into or towards the cutting device head chamber 17 defined by the cutting elements 4, 5 and an outer frame portion 12 of the support structure 14 which holds opposing edges of one of the outer cutting elements 4, as shown in FIG. 10.

[0103] More specifically, the pivot holder 41 may include a U-shaped or V-shaped retaining frame element 43 made of metal, see FIG.

[0104] A spring device 22 may be associated with the pivot axis 21 to bias the cutting device head 2 to a desired mutual pivot position or orientation, which may be an intermediate orientation allowing pivoting in the opposite direction, or alternatively an end position or orientation allowing pivoting in only one direction.

[0105] Said spring device 22 may be engaged with a support flange 43 of a pivot shaft holder 41 attached to the handle 100 on the one hand and with the outer frame 12 of the support structure 14 on the other hand.

[0106] More specifically, the pivot axis 21 may pivot relative to the handle about an eccentric pivot axis that is not symmetrically located with respect to the opposing comb-like cutting edges for cutting long hairs, such that pivoting the cutting elements 4, 5 about the pivot axis 21 results in less movement of one of the comb-like cutting edges compared to the other. More specifically, the pivot axis 21 is located offset from a mid-plane 30 that extends perpendicular to a central portion 80 of the skin-contacting / facing surfaces 50 of the cutting device elements 4, 5, such that the pivot axis 21 is closer to the first one 6 of the rows of comb-like cutting teeth than to the second one 7 of the rows of comb-like cutting teeth. When pivoting, rows closer to the pivot axis 21 make shorter lateral movements while rows further away from the pivot axis 21 make longer lateral movements, such lateral movements following a circular path around the pivot axis 21, the length of the movement depending on the distance of the row of teeth from the pivot axis 21.

[0107] More specifically, the pivot axis 21 may be located near the comb-like row of cutting teeth 6 that is typically used as a forward-advancing leading edge when moving the cutter system 3 along the skin to be shaved. Such a general direction of movement 106 that is intuitively preferred by the majority of users may depend, among other things, on the inclination of the skin-contacting / facing surface of the cutter system 3 relative to the handle 100 at the home position of the cutting elements 4, 5 relative to the pivot axis 21. Alternatively, or additionally, the direction of movement 106 preferred by the majority of users may be towards the on / off button 105 on the handle.

[0108] As can be seen from Fig. 6, in the home or neutral or initial position where the cutting elements 4, 5 are held without external forces caused by the user, the cutting elements 4, 5 may be inclined at an acute angle δ with respect to the longitudinal handle axis 110 such that the skin contacting and / or skin facing surface 50 of the cutting device elements 4, 5 faces towards the front side 108 of the handle 100 of the shaper / trimmer 1. The front side 108 of the handle is the same side of the handle where the on / off button 105 for switching the operation of the motor is located and / or where the user's thumb can be placed 107. Considering such inclination towards the front side of the cutting elements 4, 5 in the home position, the pivot axis 21 is located near the row of comb teeth 6 located on the front side, while the opposite row of comb teeth 7 located on the rear side of the handle 100 is further away from the pivot axis 21.

[0109] Because many users shave by pulling the cutting device system along the skin with the front row of teeth 6 forming a leading edge, as indicated by the arrow in FIG. 7, i.e., pointing downward in FIG. 7, locating the pivot axis 21 closer to the front row of teeth 6 can improve user comfort and reduce the risk of skin damage, such as skin irritation or cuts, that may be caused by the cutting teeth 6 pivoting against the skin or pitching too sharply toward the skin.

[0110] Essentially, if the pivot axis 21 is located directly on the leading cutting edge 6, lateral movement of the leading cutting edge 6 can be completely eliminated since there is no leverage arm or pivot radius with respect to the distance from the pivot axis. However, offsetting the pivot axis 21 too far from the center of the cutting device system 3 can compromise comfort and safety when moving the cutting device system in the opposite or undesired direction of movement over the skin to be shaved. To achieve a good compromise, the pivot axis 21 can be spaced from the first row of teeth 6 by a distance L1 that is approximately 60%-90%, or 70%-90%, or 75%-85% of the distance L2 between the opposing second row of teeth, as shown in FIG. 6.

[0111] Thus, the pivot axis 21 may be located approximately 10-40% closer to one row of teeth 6 than to the other row of teeth 7.

[0112] In order to achieve good responsiveness of the pivoting of the cutting elements 4, 5 and therefore good adaptation to the skin contours of different users who may apply different levels of skin contact pressure, the pivot axis 21 may be located close to the skin contact surface to reduce torque and frictional pivoting effects, as shown in Figure 6. When the cutting device system is pressed against the skin and moved along the skin, friction caused between the skin contact surface 50 and the skin to be shaved tends or tries to pivot the cutting device system around the pivot axis 21, as shown in Figure 7, and the lever arm of such frictional force is smaller the closer the pivot axis 21 is to the skin contact surface 50.

[0113] More specifically, the pivot axis 21 may be located slightly below the skin contact surface 50 and / or within the cutting device head chamber 17 surrounded by the opposing edge of one of the outer C-shaped cutting elements 4 and the frame part of the support structure 14 holding said cutting element 4. Such a location significantly reduces on the one hand the effect of friction forces on the pivot axis 21 and therefore the pivot torque caused by such friction forces, and on the other hand allows a compact and space-saving arrangement of the support structure 14.

[0114] To enable easy and intuitive use of the razor / trimmer, the support structure may be configured to provide a pivot range 45 for the cutting elements that is asymmetric with respect to the longitudinal handle axis 21, as shown in Figure 6. In other words, the pivot range 45 may be greater toward one side of the handle 100 than toward the opposite side of the handle 100. More specifically, the pivot range 45 may be configured such that the skin-contacting and / or skin-facing surfaces 50 of the cutting elements face toward the same side of the handle over at least 2 / 3 or 3 / 4 of the pivot range 45.

[0115] A natural razor feel and easy intuitive use can be achieved when the pivot range allows for various pivot positions of the cutting elements having inclination angles in the range of -20° to 60° or 0° to 40° ±10° or -5°, the inclination angle α being defined between an imaginary plane 46 extending perpendicular to the longitudinal handle axis 110 and another imaginary plane 47 tangent to the skin-contacting / facing surfaces 50 of the cutting elements 4, 5.

[0116] In order to bias the cutting elements 4, 5 towards their pivot home positions, the aforementioned biasing device 22 may be associated with said pivot axis 21. Such a biasing device 22 may be configured to bias the cutting elements 4, 5 towards the ends of a limited pivot range about said pivot axis 21. In other words, the biasing device, which may include a spring device, does not bias the cutting elements towards a neutral central position from which they can be pivoted in the opposite direction, but the biasing device 22 attempts to bias the cutting elements towards an extreme or end pivot position from which they can only be pivoted in one direction.

[0117] More specifically, the biasing device 22 may be configured to bias the cutting elements 4, 5 to an angular pivoted position at the smallest possible angle δ of inclination of the skin-contacting surface 50 relative to the longitudinal handle axis 110. As the cutting elements pivot from their biased home position, the plane 47 tangent to the skin-contacting surface 50 will tend to become more transverse to the longitudinal handle axis 110 and / or approach a position perpendicular to the longitudinal handle axis 110.

[0118] Due to such a biased home position, where the skin contact surface 50 is inclined at a fairly small angle δ to the longitudinal handle axis 110, the user intuitively pulls the cutter system 3 so that the above-mentioned first row of cutting teeth 6 advances over the skin to be shaved. The eccentric or offset pivot axis 21 thus allows fine adaptation of the cutting elements to the skin contours and avoids uncontrolled lateral movements that potentially pose a risk of skin irritation.

[0119] Irrespective of such preferred direction in which the cutting device system is moved, biasing the cutting elements 4, 5 to their home position at the end of the pivot range can also reduce the risk of skin irritation or even skin damage when the cutting device system moves over the skin to shave in the unpreferred opposite direction, i.e. when the second row of comb-like cutting teeth 7 is at the leading edge, as the second row of comb-like cutting teeth 7 can flex quite easily upon pivoting and give way to the skin, and only a very low skin contact force is required at the opposite edge, since the distance to the pivot axis 21 is quite large and therefore the effect of such skin contact force at the opposite edge is large.

[0120] To drive the cutting elements 4 and 5 in a reciprocating manner relative to each other, a drive 18 may be connected to the inner cutting element 5, said drive 18 may comprise rod-like drive elements attached to the opposite end portions of the inner cutting element 5. On the other hand, said drive 18 may comprise a coupling section 18c coupled to a drive element extending from the handle 100 to the cutter head 2. More specifically, the inner frame 11 and the outer frame 12 of the support structure 14 may comprise an elongated recess 23 or cutout extending through the base section 20 of the support structure 14, said coupling section 18c of said drive 18 may extend through the elongated cutout 23, referring to Figs. 5 and 4, to allow coupling with a drive element of a drive train coming from a motor in the handle 100.

[0121] The drive device 18 may be slidably guided in the inner frame 11 and / or the outer frame 12. For example, one or more guide blocks 24 or supports 24 may be provided in the outer frame 12. For example, such a guide block 24 may be inserted into a central elongated recess 23 extending into a base portion of the outer frame 12, and the guide block 24 may include a slot-like groove 25 in which the rod-like drive device 18 may be slidably guided.

[0122] The drive 18 may be housed between the rigid support ribs 19 of the inner frame 11. Specifically, the drive 18 may be housed within an inner sub-chamber 17i and thus surrounded by a chute-like insert forming the inner frame 11 including the rigid support ribs 19, and a coupling section 18c of the drive 18 may extend through a central elongated recess 23 in a bottom portion of the insert forming the inner frame 11.

Claims

1. A cutting device system for an electric shaver and / or trimmer (1), comprising a pair of cooperating cutting elements (4,5) having two rows (6,7) of comb-like cutting teeth on opposite edges thereof, and a skin contacting or skin facing surface (50) of said cutting elements (4,5), said cutting elements (4,5) being movably supported relative to one another by a support structure (14) providing a pivot axis (21) about which said cooperating cutting elements (4,5) can pivot to follow the contour of the skin, said pivot axis (21) extending substantially parallel to the longitudinal direction of said rows (6,7) of comb-like cutting teeth, said pivot axis (21) being adapted to rotate said cutting elements (4,5) in a direction ... and wherein the cutting elements (4, 5) are offset from a mid-plane (30) extending perpendicular to a central portion (80) of the skin-contacting surface (50) or skin-facing surface of the electric shaver (100) such that the cutting elements (4, 5) are closer to a first one (6) of the rows of comb-like cutting teeth than to a second one (7) of the rows of comb-like cutting teeth, the cutting device system further comprising a biasing device (22) for biasing the cutting elements (4, 5) towards a home position about the pivot axis (21), the pivot axis (21) having a portion fixed relative to one of the cutting elements (4) and a portion fixed relative to a handle (100) of the electric shaver and / or trimmer (1).

2. 2. The cutting device system according to claim 1, wherein at least one area of ​​cutting perforations (8) between the rows of comb-like cutting teeth (6, 7) is provided, the cutting perforations (8) being formed in the skin contacting surface (50) or the skin facing surface of the cutting element (4, 5).

3. 3. The cutting device system according to claim 1 or 2, wherein a first row (6) of the comb-like cutting teeth closer to the pivot axis (21) forms a front row (6) of the comb-like cutting teeth at a leading edge of the cutting element (4, 5) when the cutting element (4, 5) is moved along the skin in a movement direction (106) towards an on / off button (105) of the handle (100).

4. 4. The cutting device system according to claim 1, wherein in the home position of the cutting elements (4, 5) relative to the pivot axis (21), the cutting elements (4, 5) are inclined at an acute angle (δ) relative to a longitudinal handle axis (110) of the handle (100).

5. 5. The cutting device system of claim 4, wherein the inclination of the cutting elements (4, 5) in the home position is provided such that the skin contacting or skin facing surfaces of the cutting elements (4, 5) face towards a front side (108) of the handle (100), a first row (6) of the comb-like cutting teeth closer to the pivot axis (21) faces towards the front side (108) and a second row (7) of the comb-like cutting teeth faces towards the opposite back side.

6. 6. The cutting device system according to claim 1, wherein the pivot axis (21) is spaced from the first row of comb-like cutting teeth (6) by a distance (L1) in the range of 60% to 90%, or 70% to 90%, or 75% to 85% of a distance (L2) between the pivot axis (21) and the second row of comb-like cutting teeth (7).

7. 7. The cutting device system of any one of claims 1 to 6, wherein the pivot axis (21) is located slightly below the skin contacting or skin facing surfaces of the cutting elements (4, 5) and / or extends within a cutting device head chamber (17) contained within the cutting elements (4, 5) and an outer frame portion (12) of the support structure (14) that holds opposing edges of one of the cutting elements (4).

8. 8. The cutting device system according to any one of claims 1 to 7, wherein the support structure (14) is configured to provide a pivot range (45) around the pivot axis (21), the pivot range (45) being asymmetric with respect to a longitudinal handle axis (110) of the handle (100), and the skin contacting or skin facing surfaces of the cutting elements (4, 5) face towards the same side of the handle (100) over at least 2 / 3 or at least 3 / 4 of the pivot range (45).

9. 9. The cutting device system according to any one of claims 1 to 8, wherein the support structure (14) is configured to provide a pivot angle (α) of the cutting elements (4, 5) relative to the home position ranging from 0° to 40°±10°, the pivot angle (α) being defined between an imaginary plane (46) extending perpendicular to the longitudinal handle axis (110) of the handle (100) on the one hand, and an imaginary plane (47) tangent to the skin contacting or skin facing surface of the cutting elements (4, 5) located in the home position.

10. 10. The cutting device system according to any one of claims 1 to 9, wherein the biasing device (22) is adapted to bias the cutting elements (4, 5) towards an end of a limited pivot range (45) around the pivot axis (21).

11. 11. The cutting device system of claim 10, wherein the biasing device (22) is configured to bias the cutting elements (4, 5) to a pivoted position having the smallest possible inclination angle (δ) of the skin contacting surface (50) or skin facing surface to the longitudinal handle axis (110) of the handle (100).

12. 12. The cutting device system of any one of claims 1 to 11, wherein the support structure (14) includes a rigid pivot axle holder (41) fixedly attached to a handle (100) or chassis portion (101) of the electric shaver and / or trimmer (1), the pivot axle holder (41) including two frame portions (42) extending into or towards a cutting device head chamber defined by the cutting elements (4, 5) and an outer frame portion (12) of the support structure (14) that holds opposing edges of one of the cutting elements (4).

13. 13. The cutting device system according to claim 12, wherein the pivot holder (41) comprises a U-shaped or V-shaped holding frame element (43) made of metal.

14. 13. The cutting equipment system according to any one of claims 2 to 12, wherein the support structure (14) is configured to sandwich an inner cutting element (5) of the cutting elements between an outer cutting element (4) and a support edge of a support rib (19) of the support structure (14), a gap (16) is defined between the support edge of the support rib (19) and the outer cutting element (4), the inner cutting element (5) being movably received within the gap (16), the support structure (14) further comprising a pair of outer frame parts holding the outer cutting element (4) on its opposite edges, the support ribs extending from a base portion of the support structure (14) and preferably forming the support edges supporting the inner cutting element along an outer edge of an area of ​​a cutting perforation.

15. The support rib (19) - extending from a base portion (20) of said support structure (14) at an angle (β) of 2×20° to 2×40° or 2×25° to 2×30°; and / or - spaced apart from one another by a distance ranging from 35% to 70% or from 40% to 60% of the distance defined between the rows of comb-like teeth (6, 7) at the opposite edges of the cutting elements (4, 5); and / or 15. The cutting device system of claim 14, having a linear profile defining a V-shape and having flat, substantially parallel sides in cross-section.

16. 16. The cutting device system according to any one of claims 1 to 15, wherein at least one of the outer cutting elements (4) has a C-shape when viewed in cross section, including a pair of folded retaining flanges attached to the support structure (14) and a slightly dome-shaped or flat central section.

17. An electric shaver and / or trimmer, characterized in that it comprises a cutting device system according to any one of claims 1 to 16.

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