A shaving unit includes a cap having an annular shaving track defining an axis. The shaving track is provided with hair entry apertures which have a V-shaped forward edge with a point directed in a cutting direction. Further, a rotary cutter has a plurality of cutter blades, where the rotary cutter is configured to rotate about the axis such that the cutter blades follow the shaving track in the cutting direction to cut hairs protruding through the hair entry apertures. The cutter blades have a V-shaped cutting edge, where a point of the V-shaped cutting edge is directed opposite to the direction of rotation of the rotary cutter.

A dry shaver unit includes a housing and a cutter blade assembly mounted in the housing. The cutter blade assembly includes a cutter blade and cooperating shear blade arrangement. The thickness of the shear blade varies over its surface, such that the spacing between a portion of the skin engaging surface of the shear blade and the opposite face thereof is increased as compared with the spacing required to achieve a close shave. The cutter blade assembly is mounted in the housing such that a plurality of portions of the shear blade having different thicknesses are simultaneously available for application to a surface to be shaved.

A rotary electric shaver includes a gear case arranged inside a head unit, a lower gear arranged in a lower portion of the gear case, coaxially having an outer blade gear for driving an outer blade and an inner blade gear for driving an inner blade, an upper gear arranged in an upper portion of the gear case to drive the outer blade, and a transmission gear having an input gear arranged in the lower portion of the gear case and to which driving power is input from the lower gear, and an output gear arranged in the upper portion of the gear case to drive the upper gear, in which the input gear and the output gear are coaxial and a rotary shaft vertically penetrates the gear case. The driving power from the upper gear drives an outer blade drive gear for driving the outer blade.

Electric shaver (1) having a main body (3) and a shaving unit (5) coupled to the main body. The shaving unit has three hair-cutting units (9a, 9b, 9c) each having an external cutting member (11) with a skin-contact surface (13) with hair-entry openings (15) and an internal cutting member (17) which is rotatable relative to the external cutting member. The hair-cutting units each have at least one geometric parameter (w) that influences a hair-cutting process of each individual hair-cutting unit. The shaving unit can be positioned relative to the main body in at least two different angular positions about a central axis (37) of the shaving unit. A value of the geometric parameter of at least one of the hair-cutting units is different from the values of the geometric parameter of the other hair-cutting units.

A hair-cutting unit (9a) comprises an external cutting member (11a) and an internal cutting member (13a) rotatable relative to the external cutting member about a central axis. The external cutting member comprises hair-entry slots (35) having a slot angle () in a range from 0 to 20 in each radial position of the hair-entry slot. The internal cutting member comprises cutting elements (59a, 59b, 59c) each having a cutting edge (45a, 45b, 45c) having a cutting-edge angle () in a range from 55 to 85. A trailing edge (43) of each hair-entry slot is provided with a hair-retaining structure (47) having an array of hair-abutment surfaces (53) extending transversely relative to the trailing edge and facing the central axis (19).

An electric shaver (1) comprises at least one hair-cutting unit (9a, 9b, 9c) having a central axis (11), an external cutting member (13) with hair-entry openings (61), and an internal cutting member (15). The internal and external cutting members are rotated about the central axis, respectively, in a first rotational direction (R1) and at a first rotational speed (1) and in a second rotational direction (R2) opposite to the first rotational direction and at a second rotational speed (2) lower than the first rotational speed. The hair-entry openings comprise a V-shaped opening portion (63) pointing opposite to the second rotational direction (R2). A tangential speed (VT) of the external cutting member relative to the central axis (11), measured in a radial position (RC) of a central base point (65) of the V-shaped opening portions, is in a range between 7.5 and 50 cm/s.

An electric shaver (1) comprises at least one hair-cutting unit (9a, 9b, 9c) having a central axis (11), an external cutting member (13) with hair-entry openings (61), and an internal cutting member (15). The internal and external cutting members are rotated about the central axis, respectively, at a first rotational speed (1) and at a second rotational speed (2) and such that the internal and external cutting members are rotated relative to each other. The electric shaver further comprises a detection system (87) for measuring at least one user-related parameter (URP) relating to skin or hairs of a user of the electric shaver or relating to manipulation of the electric shaver by the user relative to a body of the user. The electric shaver further comprises a processor (89) for controlling the second rotational speed (2) of the external cutting member in dependence on the at least one measured user-related parameter.

A hair-cutting unit (4) for use in a hair-cutting appliance comprises an external cutting member (5) having hair-entry openings in a cutting track surface (58), an internal cutting member (6) having at least one hair-cutting element and being movable with respect to the external cutting member (5), and a skin-supporting structure (7) having a skin-supporting surface (71) for contacting a portion of skin to be subjected to a hair-cutting action. The external cutting member (5) is displaceable relative to the skin-supporting structure (7), and the hair-cutting unit (4) further comprises a safety mechanism which is designed to enable stepped and instantaneous variation between at least two discrete stages of a level (l.sub.c) of the cutting track surface (58) with respect to a level (l.sub.s) of the skin-supporting surface (71), in relation to pressure exerted by the external cutting member (5) on the skin.

In the field of skin treatment, a device (40) is provided which is of the type comprising a housing (41) provided with a skin-contacting surface (42) arranged to be in contact with skin (100) of a user. At least one light source (50) is arranged in the housing (41) for generating treatment light to be applied to the skin (100) via a light-transmitting portion (43) of the skin-contacting surface (42), wherein the light source (50) is mounted on a first side (61) of a carrier (60), said first side (61) facing away from the skin-contacting surface (42), and wherein the housing (41) accommodates an optical reflector (70). Further, at least a portion of a second side (62) of the carrier (60) is mounted to an inner side of a wall portion of the housing (41) including part of the skin-contacting surface (42), or constitutes part of the skin-contacting surface (42).