Shaving apparatus with improved cap functionality

Abstract

A shaver includes a housing and at least one cutter accommodated by the housing. Each cutter includes an external cutting member and an internal cutting member which is rotatable relative to the external cutting member about an axis of rotation. A locking system is configured and arranged to prevent rotation of the external cutting member relative to the housing. The locking system includes an annular array of N1 first arresting elements and N2 second arresting elements, wherein N1?8 and 1?N2?N1. The N2 second arresting elements are configured and arranged to be each engageable with a respective one of the N1 first arresting elements in any of N1 angular positions of the external cutting member about the axis of rotation relative to the housing.

Claims

1. A shaving unit comprising a housing and at least one cutting unit accommodated and supported by the housing, wherein each cutting unit comprises: an external cutting member having a plurality of hair-entry openings provided in a skin contacting surface of the external cutting member; and an internal cutting member which is rotatable relative to the external cutting member about an axis of rotation; wherein the shaving unit comprises, for each cutting unit, a locking system configured and arranged to prevent, during use, rotation of the external cutting member of the respective cutting unit relative to the housing at least in a rotational direction of the internal cutting member about the axis of rotation, said locking system comprising a first locking member connected to one of the housing and the external cutting member and a second locking member connected to the other one of the housing and the external cutting member for cooperation with the first locking member, wherein the first locking member comprises an annular array of N1 first arresting elements which are concentrically arranged relative to the axis of rotation with a uniform distribution about the axis of rotation and abut each other at an entire outer periphery of the one of the housing and the external cutting member, and wherein the second locking member comprises N2 second arresting elements, and wherein: N1?8 and 1?N2?N1; the N2 second arresting elements are configured and arranged to be each engageable with a respective one of the N1 first arresting elements in any of N1 angular positions of the external cutting member about the axis of rotation relative to the housing; each of the N2 second arresting elements is configured and arranged to prevent rotation of the external cutting member relative to the housing in said rotational direction by engagement with the respective one of the N1 first arresting elements in any of the N1 angular positions of the external cutting member, the locking system is configured to rotate the external cutting member about the axis of rotation to engage the N2 second arresting element with the N1 first arresting element to angularly self-adjust the external cutting member verses the housing by flanks of a triangular geometry of the first and second arresting elements.

2. The shaving unit as claimed in claim 1, wherein N1?16.

3. The shaving unit as claimed in claim 1, further comprising a supporting structure for supporting the external cutting member relative to the housing, wherein the supporting structure has a first supporting member having an inclined surface, wherein the supporting structure has a second supporting member having a post that protrudes from the second supporting member, wherein the housing has a skin supporting surface surrounding the external cutting member, and wherein the exposure distance between the skin supporting surface and the skin contacting surface is adjustable by a discrete number of the N1 angular positions to lock the external cutting member at a selected exposure distance in response to changing an angular position of the external cutting member about the axis of rotation relative to the housing by rotation of the external cutting member about the axis of rotation for rotating the inclined surface over the post and engagement of the N2 second arresting elements with different ones of the N1 first arresting element of the external cutting member.

4. The shaving unit as claimed in claim 1, wherein the housing comprises a base portion and, for each cutting unit, a respective skin supporting member surrounding the external cutting member, wherein in each cutting unit the respective one of the first and second locking members connected to the housing is connected to the respective skin supporting member.

5. The shaving unit as claimed in claim 1, wherein each of the N1 first arresting elements is an indentation provided in an annular surface of the first locking member extending perpendicularly to the axis of rotation, and wherein each of the N2 second arresting elements is a protrusion provided on the second locking member and configured and arranged to be engageable with a respective one of the N1 indentations in any of the N1 angular positions of the external cutting member by a motion of the external cutting member relative to the housing in a direction parallel to the axis of rotation during assembly of the cutting unit.

6. The shaving unit as claimed in claim 5, wherein the indentation and the protrusion are triangular.

7. The shaving unit as claimed in claim 1, wherein each of the N1 first arresting elements is an indentation provided in a cylindrical surface of the first locking member arranged concentrically relative to the axis of rotation, and wherein each of the N2 second arresting elements is an elastic spring element provided on the second locking member and configured and arranged to be engageable with a respective one of the N1 indentations in any of the N1 angular positions of the external cutting member by a biasing force of said spring element in a radial direction relative to the axis of rotation.

8. The shaving unit as claimed in claim 1, wherein the housing has a skin supporting surface surrounding the external cutting member, wherein the skin contacting surface of the external cutting member which protrudes relative to the skin supporting surface in an axial direction parallel to the axis of rotation over an exposure distance between the skin supporting surface and the skin contacting surface, and wherein the shaving unit comprises, for each cutting unit, a supporting structure for supporting the external cutting member relative to the housing in at least said axial direction, the supporting structure defining at least a minimum value of said exposure distance and being configured and arranged such that said minimum value is dependent on an angular position of the external cutting member about the axis of rotation relative to the housing.

9. The shaving unit as claimed in claim 8, wherein the supporting structure comprises a first supporting member connected to one of the housing and the external cutting member and a second supporting member connected to the other one of the housing and the external cutting member for cooperation with the first supporting member, wherein the first supporting member comprises at least two supporting surface segments which are each inclined with respect to a tangential direction relative to the axis of rotation, and wherein the second supporting member comprises at least two abutment elements which are each configured and arranged for abutment against a respective one of the at least two supporting surface segments in the axial direction relative to the axis of rotation.

10. The shaving unit as claimed in claim 9, wherein the respective one of the first and second supporting members connected to the external cutting member is integrally formed with the plastic carrier.

11. The shaving unit as claimed in claim 9, wherein the first supporting member is connected to the housing, wherein the at least two supporting surface segments are provided in a guiding channel provided in a cylindrical inner wall of the housing surrounding the external cutting member, wherein the second supporting member is connected to the external cutting member, and wherein the at least two abutment elements engage said guiding channel.

12. A shaving apparatus comprising a main body accommodating a drive system and further comprising a shaving unit as claimed in claim 1 coupled to the main body.

13. The shaving unit of in claim 1, further comprising an indication of a height level of the skin contacting surface.

14. The shaving unit of in claim 1, further comprising a first indication of a raised level of the skin contacting surface and a second indication of a lowered level of the skin contacting surface.

15. The shaving unit of in claim 14, wherein the first and second indications are different colors.

16. A shaver omprising a housing and a cutter supported by the housing, wherein the cutter comprises: an external cutter having a plurality of hair-entry openings provided in a skin contacting surface of the external cutter member; and an internal cutter rotatable relative to the external cutter about an axis of rotation; and a locking system configured to prevent, during use, rotation of the external cutter relative to the housing at least in a rotational direction of the internal cutter about the axis of rotation, wherein the locking system comprises a first locking member connected to one of the housing and the external cutter and a second locking member connected to the other one of the housing and the external cutter for cooperation with the first locking member, wherein the first locking member comprises an annular array of N1 first arresting elements which are concentrically arranged relative to the axis of the rotation, and wherein the second locking member comprises N2 second arresting elements, and wherein the locking system is configured to rotate the external cutting member about the axis of rotation to engage the N2 second arresting element with the N1 first arresting element to angularly self-adjust the external cutting member verses the housing by flanks of a triangular geometry of the first and second arresting elements.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following drawings:

(2) FIG. 1 shows a perspective view of a shaving apparatus according to the invention,

(3) FIG. 2 shows a perspective lateral top view of a first embodiment of a shaving unit according to the invention comprised by the shaving apparatus of FIG. 1, with one cutting unit being opened,

(4) FIG. 3 shows a perspective lateral bottom view of a housing component and a locking system component of the first embodiment of the shaving unit,

(5) FIG. 4 shows a perspective bottom view of a housing component and a locking system component of a second embodiment of the shaving unit according to the invention,

(6) FIG. 5 shows a perspective lateral bottom view of a housing component and a locking system component of a third embodiment of the shaving unit according to the invention,

(7) FIG. 6 shows a perspective lateral bottom view of a housing component and a locking system component of the third embodiment of the shaving unit,

(8) FIG. 7 shows a bottom view of the components of the third embodiment of the shaving unit,

(9) FIG. 8 shows a sectional lateral view of a fourth embodiment of a shaving unit according to the invention,

(10) FIG. 9 shows a perspective bottom lateral view of a locking system component of the fourth embodiment of the shaving unit,

(11) FIG. 10 shows a perspective bottom view of locking system components of a fifth embodiment of a shaving unit according to the invention,

(12) FIGS. 11A, B show a schematic view of a locking system and exposure adjustment means of the fourth embodiment of the shaving unit,

(13) FIG. 12 shows a schematic view of a manual exposure adjustment means of the fifth embodiment of the shaving unit,

(14) FIG. 13 shows a perspective bottom lateral view of a housing component of a sixth embodiment of a shaving unit according to the invention,

(15) FIG. 14 shows a perspective top lateral view of locking system components of the sixth embodiment of the shaving unit,

(16) FIG. 15 shows a perspective bottom lateral view of a housing component of a seventh embodiment of a shaving unit according to the invention, and

(17) FIG. 16 shows a perspective top lateral view of locking system components of the seventh embodiment of the shaving unit.

DETAILED DESCRIPTION OF EMBODIMENTS

(18) FIG. 1 shows a rotary shaving apparatus according to the invention, comprising a main body or handle portion 1 and a first embodiment of a shaving unit 2 according to the invention, which is detachable from the main body 1 and/or is hinged to the main body 1. Two rotary cutting units 3a, 3b, also denoted shaving heads, are arranged in the shaving unit 2, each having an external cutting member 4 with hair trap openings s-and an internal cutting member 30 (FIG. 2) with cutter elements, which can be driven into rotation with respect to the external cutting member 4 about three axes of rotation with one axis of rotation associated to each cutting unit. The cutting units 3a, 3b may be pivotable about a single axis or multiple axes to be able to follow the contour of the skin of the user such as to provide comfortable shaving. Thus, the axes of rotation may change their orientation with respect to the main body 1 upon tilting of the cutting unit 3a, 3b. This change of orientation may be synchronized between the cutting units or may be independently for each of the cutting units. The internal cutting member is driven by a drive unit like an electric motor accommodated in the main body 1 which may further comprise various components like e.g. a rechargeable battery, a drive unit, a control unit and an interface for controlling and charging the shaving apparatus. Below the rotary cutting units a gear component may be provided, wherein the driving force of the drive unit inside the main body 1 is transmitted and distributed to the cutting units. It should be understood that two (as depicted in FIG. 1), three, four or more such cutting units could be provided at the shaving unit as well as only one single cutting unit could be comprised in the shaving unit.

(19) Making reference to FIG. 2, the first embodiment of the shaving unit 2 of the shaving apparatus is shown in detail, wherein the left cutting unit 3a is shown in an opened position. As can be seen, the cutting unit 3a is mounted in a shaving unit comprising an upper housing part 10 and a bottom housing part 11, which are connected via a hinge-type connection allowing the upper housing part 10 to be pivoted about an axis in relation to the bottom housing part 11 such as to allow access to the interior of the housing 10, 11.

(20) An external cutting member 20 is mounted to the upper housing part 10. The external cutting member 20 is formed as a circular cap with an upper skin contacting surface 21b as can be seen from the right, non-opened cutting unit in FIG. 2. The external cutting member 20 is mounted to the upper housing part 10 and locked against rotation about the axis of rotation 5a by a locking system. The upper housing part 10 defines a skin supporting surface 12b as can be seen in the right hand cutting unit of FIG. 2. This skin supporting surface 12b circumscribes the skin contacting surface 21b of the external cutting member. In the skin contacting surface 21b, a plurality of radially extending slots are provided in a circular arrangement. These are the hair entry openings forming a circular shaving track.

(21) Still further, an internal cutting member 30 is positioned adjacent to the external cutting member and is able to rotate about the axis of rotation 5a in relation to the external cutting member. The internal cutting member 30 comprises a central coupling recess of a triangular shape to couple with a spindle head 31 of the drive gear. Via this spindle head 31 the internal cutting member is driven into rotation and at the same time is able to follow a pivoting movement of the external cutting member when following the contour of the skin.

(22) The bottom housing part 11 comprises an annular hair collection chamber 19. A holder 40 is pivotally mounted to the bottom housing part 11 to support and hold the external cutting member 20 in its position at the upper housing part 10.

(23) Making reference now to FIG. 3, an upper housing part 110 and a second locking member 160 of the locking system of the first embodiment of the shaving unit according to the invention is shown in a perspective lateral bottom view. As can be seen, the upper housing part 110 comprises a plurality of integrally formed indentations or recesses 150a, b, c, . . . arranged in an annular arrangement at the outer periphery of the upper housing part. These indentations face downward towards the bottom housing part (not shown). These indentations form a plurality of first arresting elements and said plurality of first arresting elements form a first locking member of the locking system.

(24) The indentations 150a, b, c, . . . are formed as triangular indentations with a base of the triangle forming the opening of the recess and the tip of a triangle forming the bottom end of the indentation. As can be seen, the indentations 150a, b, c . . . are arranged in direct neighborhood to each other such that between two adjacent recesses, a triangular protrusion is formed, said protrusion having a triangular geometry with the tip facing towards the bottom housing part.

(25) The second locking member 160 is ring-shaped and is provided as a separate plastic carrier. It forms in connection with the first locking member and the indentations 150a,b,c, . . . formed at this first locking member the locking system for preventing rotation of the external cutting member relative to the housing. The second locking member 160 comprises four protrusions disposed about the second locking member in an angular distance of 90? to each other such that the protrusions are evenly distributed along the periphery of the ring-shaped component. The protrusions form second arresting elements and face towards the upper housing part 110. The protrusions are formed as triangular protrusions with the tip facing towards the upper housing part 110. By this, the protrusions of the second locking member match exactly with the indentations formed integrally as first locking member at the upper housing part 110.

(26) The second locking member may be positioned in a large number of predefined angular positions relative to the second locking member at the upper housing part 110 with respect to the axis of rotation 5a with the protrusions being form-locked in any of the indentations 150a,b,c, . . . formed in the upper housing part. By this, the second locking member may easily be mounted to the first locking member in such form-locking engagement, since no particular single orientation or angular position must be adjusted or maintained for such assembling process. Still further, by the assembling process comprising insertion of the triangular protrusion into the triangular indentation, a slight angular misalignment will be automatically adjusted by the locking system such that the protrusions are guided by themselves into a full form-locking engagement into the indentation by a guiding function of the flanks of triangular geometry.

(27) The ring-shaped second locking member 160 further comprises four radially inward protruding teeth 162a,b, which allow fixing the ring-shaped second locking member 160 to the external cutting member. With the ring-shaped second locking member fixed to the external cutting member, these teeth prevent rotation of the ring-shaped second locking member 160 in relation to the external cutting member and thus, the external cutting member can be form-locked against rotation about the axis of rotation 5a by said form-locking engagement of the protrusions 161a,b, . . . inside the indentations 150a,b,c, . . .

(28) FIG. 4 shows a bottom perspective view of a second embodiment of the shaving unit according to the invention. In this embodiment, a ring-shaped first locking member 260 is employed and firmly attached to the external cutting member 220 being placed in the upper housing part 210. The ring-shaped first locking member comprises a plurality of more than eight radially extending indentations or notches 261a, b, c forming first arresting elements. As can be seen, the indentations 261a, b, c have a triangular geometry similar to a sawtooth-like pattern. Thus, this design provides a first, short side of each indentation or notch lying in a radially extending plane with respect to the axis of rotation or in a plane having a small angle to such radially extending plane. Further, a long side of the triangular geometry lies in a plane oriented in a small angle to a tangential plane to the ring-shaped first locking member, i.e. having a main component in a circumferential direction.

(29) A second locking member 250 integrally formed at the upper housing part 210 engages the indentations 261 a, b, c of the ring-shaped first locking member 260. As can be seen, the second locking member 250 comprises a protrusion forming a single second arresting element acting against the short side of one of the triangular indentations 261a, b, c and hereby locks the first locking member and the external cutting member attached thereto against a clockwise rotation when seen from the bottom according to FIG. 4. This locking against the clockwise rotation is functionally relevant because the internal cutting member 230 is driven into a corresponding clockwise rotation and thus may impart a torque into such clockwise direction to the external cutting member.

(30) The first locking member 260 may rotate counter-clockwise by flexible bending of the second locking member 250 in a radial outward direction. This outward bending is caused by the long side of the triangular indentations forming the first arresting elements. By this, a ratchet-like mechanism is provided by the interaction of the indentations 261a-c and the second locking member 250. Further, it can be seen that the first locking member may be form-locked against rotation in a clockwise direction in a total of twenty-four angular positions corresponding to the number of twenty-four indentations 261a, b, c, . . . thus making it quite easy for a user to assemble this arrangement with a safe form-locking of the external cutting member.

(31) FIG. 5 and FIG. 6 show bottom perspective views of the locking system of a third embodiment of a shaving unit according to the invention. A ring-shaped second locking member 360 is attached to the external cutting member 320 via a form-locking clipping engagement. The ring-shaped second locking member 360 comprises three radially protruding tabs 361a,b,c which are flexible for an elastic movement in a radially extending direction. The flexible tabs 361a, b, . . . form protrusions acting as second arresting elements and engage with a first locking member having a toothed pattern 350, 351, 352 in three segments of a ring-shaped enclosure circumscribing the opening in the upper housing part 310 taking up the external cutting member. Each of the three toothed segments in the second locking member comprises a plurality of indentations 350a,b,c, 351a,b,c. By this, each of the tabs 361a, b may engage one of said plurality of indentations and thus, the external cutting member may be positioned inside the upper housing part 310 in a plurality of different angular positions. In this embodiment, a total of eight different angular positions is available corresponding to the eight protrusions in each of the toothed pattern 350a, b, c, . . . 351a,b,c, . . . .

(32) FIG. 7 shows a top view of the third embodiment with the ring-shaped second locking member 360 shown inside the opening of the upper part housing 310, wherein the external cutting member is not shown in this embodiment for better view of the locking function.

(33) Reference is being made now to FIGS. 8-16. An additional functionality of the locked external cutting member inside the housing is explained. As can be seen in the sectional view of FIG. 8 relating to a fourth embodiment of a shaving unit according to the invention, the upper part of the housing 410 defines an angular skin supporting surface 412 surrounding a skin contacting surface 421 along a shaving track of the external cutting member 420 (cap). An exposure distance 425 (cap exposure) of the skin contacting surface 421 versus the skin supporting surface 412 is defined as the axial displacement in the direction of the axis of rotation 5a. This exposure distance 425 is a characteristic defining the balance of efficiency versus comfort of the shaving action. Whilst a large positive protruding exposure distance 425 of the skin contacting surface 421 over the skin supporting surface 412 will produce an efficient shaving function with less comfort function, a small positive exposure distance 425 or a flush arrangement of the skin supporting surface 412 and the skin contacting surface 421 or even a negative exposure distance 425 with the skin contacting surface lying below the skin supporting surface will produce an increased comfort function of the shaving procedure with reduced shaving efficiency.

(34) The exposure distance 425 may be set according to the personal preferences of the user. As can be seen in FIG. 9, a ring-shaped second locking member 460 having four distinct protruding triangular protrusions 461a, b, . . . similar to the protrusions 161a, b, . . . is provided in this embodiment to effect the form-locking function for anti-rotating locking of the external cutting member 420. The ring-shaped second locking member 460 of FIG. 9 is different from the ring-shaped second locking member 160 of FIG. 3, in that the axial bottom face is not formed as an even axial annular face. Instead, this axial face is formed by four ramp segments 465a, b, c, d. These ramp segments 465a-d define a sloped geometry on the bottom side of the second locking member 460.

(35) This segmented sloped geometry is used as an abutting surface inside the cutting unit to support the external cutting member. The support may be provided by a holder, e.g. formed like the holder 40 shown in FIG. 2 or may be provided by corresponding abutting supports integrally formed at the bottom part of the housing. Such abutting support posts are schematically shown in FIG. 11A, B as posts 445. Upon mounting the second locking member 460 to an upper housing part 110, as shown in FIG. 3, the user may select a specific angular position of the second locking member 460 versus the housing 110. By this, support posts provided to abut the ramp surfaces 465a-d will define a specific axial displacement of the external cutting member 420 attached to said ring-shaped second locking member 460 in relation to the housing 410. This axial displacement will depend on the position of the posts along the periphery of the abutting ramp surfaces 465a-d. By this, the user may adjust the distance 425 and thus the degree of efficiency versus comfort of the shaving function.

(36) A single or each of the four ramp segments 465a, b, c, d is divided into a plurality of differently colored segments. The colors are ranging from green to red. By this, the user may be given a color signal through a window or opening or the like about the degree of cap exposure.

(37) The specific interaction and functionality of adjusting the cap exposure distance is schematically shown in FIGS. 11A, B shows a first supporting member 464 comprising at least two supporting surface segments 465a, 465b, 465c, 465d (FIG. 9) and a second supporting member 440 comprising at least two abutment elements 445. As can be seen in FIG. 11A, the protrusion 461a may be positioned such that the abutting post 445 is positioned approximately in the middle of the ramp segment, thus effecting a first height level of the skin contacting surface 421. FIG. 11B shows a different positioning of the protrusion 461a in a different indentation at the upper part housing. In this position, the post abuts the ramp surface close to the maximum ramp level, thus producing a raised level of the skin contacting surface 421. The difference between the two levels is shown in FIG. 11A, B and labelled as h. The maximum difference of the level of the skin contacting surface is shown as h. being the difference of the minimum ramp level to the maximum ramp level. Positioning the protrusion 461a at the minimum ramp level will effect a minimum exposure distance.

(38) FIG. 10 shows a ring-shaped first locking member 560 of a fifth embodiment of a shaving unit according to the invention, which is similar to the ring-shaped first locking member shown in FIG. 4, wherein the form-locking indentations 561a, b, c, . . . extend in a radial direction. This first locking member 560 comprises a bottom ring-shaped abutting surface similar to the second locking member 460 of FIG. 9 having 4 ramp segments 565a, b, c, d with a ramp extending in an axial direction with respect to the axis of rotation 5a of the external cutting member 520. Again, a color code from green to red is applied such that a color signal of the cap exposure distance can be given to the user.

(39) FIG. 12 shows a mechanism for adjusting the height level of the skin contacting surface by rotating the ring-shaped first locking member 560 in the fifth embodiment of the shaving unit. To effect such rotation, a ratchet-like element 570 is provided radially outward of the ring-shaped first locking member 560. This ratchet-like element 570 has a handle portion 571 protruding through an opening 515 in the housing 511 of the shaving unit, whereby this handle portion 571 of the ratchet-like element 570 can be actuated by a finger of the user from outside the cutting element. The ratchet-like element is biased into a position abutting one end of the opening 515 by a spring 572. The user may move the ratchet-like element 570 in a counter-clockwise direction about a certain angular range defined by the angular extension of the opening 515. Upon such movement in a circumferential direction, a flexible tab 573 forming a second arresting element integral with the element 570 engages the short flank of the triangular indentations 561a, b, c of the ring-shaped locking element 560 and rotates the ring-shaped first locking member 560 in a counter-clockwise direction. A further flexible tab 550 mounted to the housing 511 forms an additional protrusion acting as a second arresting element. This tab 550 will effect a locking of the ring-shaped locking element in the counter-clockwise rotated position effected by such movement of the ratchet-like element. The user may thus move the ratchet-like element 570 clockwise following the force of the spring 572 back to its initial position without the ring-shaped locking element following this movement. By this, the first locking member 560 can be rotated counter-clockwise in a stepwise fashion to effect adjustment of the level of the skin contact surface.

(40) FIGS. 13 and 14 show an exposure distance adjustment mechanism for the skin contacting surface in a sixth embodiment of a shaving unit according to the invention. In this embodiment, the ramped surface is not provided at the ring-shaped locking element, but alternatively embodied in the upper housing part 610. As can be seen, a ramped surface is defined by a guiding slot 615, formed in an inner cylindrical wall surrounding the opening in the upper housing part, which takes up the external cutting member. The external cutting member 620 is attached to a ring-shaped first locking element 660 having multiple radially extending indentations similar to the ring-shaped locking member 260 and the ring-shaped locking member 560. Further, this ring-shaped first locking member 660 comprises short rail segments 666 engaging the ramped slot 615 in the upper housing part 610. By this, a rotation of the first locking member 660 together with the external cutting member 620 will effect an adjustment of the height level of the skin contacting surface 621 by such guiding of the rail segments inside the ramped slot 615.

(41) Still further, FIGS. 15 and 16 show the components of a seventh embodiment of a shaving unit according to the invention comprising an exposure distance adjustment mechanism for the skin contacting surface relative to the skin supporting surface. In this embodiment, the locking system for locking the external cutting member against rotation is formed in a similar manner as shown in the embodiment of FIG. 6. Still further, a ramped surface is provided in the inner cylindrical wall of the upper housing part 710 as a ramped shoulder 715. Additionally, as can be seen in FIG. 16, the bottom surface of the first locking member 760 is formed by four ramp segments 765a,b,c similar to the ramp segments 465a-d of the embodiment shown in FIG. 9. The ring-shaped locking element 760 is equipped with tabs each having an axially abutting surface 766 which abuts the ramped shoulder 715 inside the upper housing part 710. In contrast to the embodiment shown in FIGS. 13, 14, this embodiment does not require a guiding slot in the form of a ramped notch engaging a rail segment, but rather uses the ramped shoulder forming a ramped axial abutting surface in the upper housing part 710. This ramp surface 715 limits the axial movement of the ring-shaped first locking member 760 in the direction upwards whilst the ring-shaped first locking member 760 is supported on the bottom side by the ramped surface 765a, b, c, thus limiting the axial movement in the opposite direction.

(42) Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

(43) In the claims, the word comprising does not exclude other elements or steps, and the indefinite article a or an does not exclude a plurality.

(44) A single unit or device may fulfill the functions of several items recited in the claims. 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. Any reference signs in the claims should not be construed as limiting the scope.

(45) The invention relates to a shaving unit comprising a housing and at least one cutting unit accommodated by the housing. Each cutting unit comprises an external cutting member and an internal cutting member which is rotatable relative to the external cutting member about an axis of rotation. A locking system is configured and arranged to prevent rotation of the external cutting member relative to the housing. Said locking system comprises an annular array of N1 first arresting elements and N2 second arresting elements, wherein N1?8 and 1?N2?N1. The N2 second arresting elements are configured and arranged to be each engageable with a respective one of the N1 first arresting elements in any of N1 angular positions of the external cutting member about the axis of rotation relative to the housing.