Cutting unit and shaving head of a shaving device

Abstract

A rotary cutting unit of a shaving head of a shaving device, which cutting unit includes an external cutting member and an internal cutting member. In an interconnected condition, a holding force prevents the external and internal cutting members from moving apart. The holding force is at least exerted by a first central portion of the external cutting member upon a second central portion of the internal cutting member, and/or vice versa. The holding force may for example be provided by a snap connection or magnetic attraction between the first and second central portions.

Claims

1. A cutting unit for use in a shaving device for shaving hairs, said cutting unit comprising: an external cutting member comprising a shaving surface, wherein the shaving surface is interrupted by an apertured structure for allowing hairs to pass; and an internal cutting member, wherein the internal cutting member is drivable for rotative movement relative to the external cutting member about a rotation axis and along said apertured structure in the shaving surface of the external cutting member for cutting through hairs passing said apertured structure; and wherein: the external cutting member and the internal cutting member have: an interconnected condition, in which the external cutting member and the internal cutting member are mutually interconnected for operation of the cutting unit, and a disconnected condition, in which the external cutting member and the internal cutting member are mutually disconnected for taking the internal cutting member out of the external cutting member for cleaning the cutting unit; the external cutting member comprising a first central portion and the internal cutting member comprising a second central portion, wherein in said interconnected condition said rotation axis k a center line of the first central portion as well as of the second central portion; wherein the external cutting member k formed into a single part that includes the first central portion and wherein the internal cutting member is formed into a single part that includes the second central portion; in said interconnected condition a holding force prevents the external cutting member and the internal cutting member from moving apart into the disconnected condition; said bolding force is at least exerted by the first central portion upon the second central portion, and/or by the second central portion upon the first central portion; and said disconnected condition k obtainable from said interconnected condition by manually moving the external cutting member and the internal cutting member away from one another in a direction parallel to said rotation axis by means of a manual force action overcoming said holding force, wherein the external cutting member and the internal cutting member remain single parts respectively when in the disconnected condition, wherein the first central portion comprises a first snap connection structure, the first snap connection structure including a first radial extension and a bearing stud extending from the first radial extension and the second central portion comprises a second snap connection structure including a second radial extension, the second snap connection structure defining a cylindrical recess with an entry opening, wherein the entry opening comprises a locally decreased diameter provided by the second radial extension extending radially from a wall of the second snap connection structure, wherein the wall extends in a direction parallel to the rotation axis, and wherein the first snap connection structure and the second snap connection structure mutually co-operate for providing at least part of said holding force provided by a snap connection between the first snap connection structure and the second snap connection structure.

2. The cutting unit according to claim 1, wherein in said interconnected condition the first central portion and the second central portion are mutually co-operating portions providing radial bearing support for said rotative movement.

3. The cutting unit according to claim 1, wherein in said interconnected condition, the first snap connection structure and the second snap connection structure allow an amount of play of at least 0.4 millimeter of translational movement of the internal cutting member relative to the external cutting member in a direction parallel to said rotation axis while the internal cutting member and the external cutting member stay level with respect to each other and while the first snap connection structure and the second snap connection structure maintain said interconnected condition.

4. The cutting unit according to claim 1, wherein in said interconnected condition the first snap connection structure and the second snap connection structure provide radial bearing support for said rotative movement.

5. The cutting unit according to claim 1, wherein in said interconnected condition the first snap connection structure and the second snap connection structure allow an amount of play of at least 0.2 millimeter of translational movement of the internal cutting member relative to the external cutting member in a direction parallel to said rotation axis while the internal cutting member and the external cutting member stay level with respect to each other and while the first snap connection structure and the second snap connection structure maintain said interconnected condition.

6. The cutting unit according to claim 1, wherein in said interconnected condition, the bearing stud extends past the entry opening sufficient to provide an amount of play of at least 0.2 millimeter of translational movement of the internal cutting member relative to the external cutting member in a direction parallel to said rotation axis while the first snap connection structure and the second snap connection structure maintain said interconnected condition.

7. The cutting unit according to claim 1, wherein the first central portion and the second central portion each include a radial extension, wherein the radial extensions in said interconnected condition mutually co-operate to provide axial bearing support between the external cutting member and the internal cutting member, wherein the radial extensions are in contact with each other when the external cutting member and the internal cutting member are closest together.

8. A shaving head for use in a shaving device for shaving hairs, said shaving head comprising at least one cutting unit according to claim 1.

9. A shaving device for shaving hairs, comprising: a shaving device main body configured to be taken hold of by a user of the shaving device, and configured to accommodate various members of the shaving device; and a shaving head according to claim 8, the shaving head being connected or connectable to the shaving device main body for operation of the shaving device.

10. A shaving device for shaving hairs, the shaving device comprising: a main body configured to be taken hold of by a user of the shaving device; and a shaving head including at least one cutting unit, the shaving head being connected or connectable to the main body, for operation of the shaving device, the at least one cutting unit including an external cutting member comprising a shaving surface, wherein the shaving surface is interrupted by an apertured structure for allowing hairs to pass, and an internal cutting member, wherein the internal cutting member is drivable for rotative movement relative to the external cutting member about a rotation axis and along the apertured structure in the shaving surface of the external cutting member for cutting through hafts passing the apertured structure, wherein the external cutting member and the internal cutting member have: an interconnected condition, in which the external cutting member and the internal cutting member are mutually interconnected for operation of the at least one cutting unit, and a disconnected condition, in which the external cutting member and the internal cutting member are mutually disconnected for removing the internal cutting member from the external cutting member; wherein the external cutting member comprises a first central portion and the internal cutting member comprises a second central portion, wherein in the interconnected condition the rotation axis is a center line of the first central portion as well as of the second central portion, wherein the external cutting member is formed into a single part that includes the first central portion and wherein the internal cutting member is formed into a single part that includes the second central portion; wherein in the interconnected condition a holding force prevents the external cutting member and the internal cuffing member from moving apart into the disconnected condition; wherein the holding force is at least exerted by the first central portion upon the second central portion, and/or by the second central portion upon the first central portion; wherein the disconnected condition is obtainable from the interconnected condition by manually moving the external cutting member and the internal cutting member away from one another in a direction parallel to the rotation axis by means of a manual force action overcoming the holding force, and wherein the external cutting member and the internal cutting member remain single parts respectively when in the disconnected condition, wherein the first central portion comprises a first snap connection structure, the first snap connection structure including a first radial extension and a bearing stud extending from the first radial extension and the second central portion comprises a second snap connection structure recess with an entry opening, wherein the entry opening comprises a locally decreased diameter connection structure, wherein the wall extends in a direction parallel to the rotation axis, and wherein the first snap connection structure and the second snap connection structure mutually co-operate for providing at least part of said holding force provided by a snap connection between the first snap connection structure and the second snap connection structure.

11. The shaving device according to claim 10, wherein the first central portion and the second central portion each include a radial extension, wherein the radial extensions in said interconnected condition mutually co-operate to provide axial bearing support between the external cutting member and the internal cutting member, wherein the radial extensions are in contact with each other when the external cutting member and the internal cutting member are closest together.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above mentioned aspects and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter by way of non-limiting examples only and with reference to the schematic figures in the enclosed drawing.

(2) FIG. 1 shows, in a perspective view, an example of a shaving device according to the invention, which shaving device comprises an example of a first embodiment of a shaving head according to the invention.

(3) FIG. 2 separately shows, in a perspective view, said first embodiment of the shaving head again, however, this time in an opened condition of the shaving head.

(4) FIG. 3 separately shows, in a perspective view, one of three identical cutting units according to an embodiment of the invention of said first embodiment of the shaving head in a disassembled condition of the shown cutting unit, hereinafter also referred to as (the) first cutting unit, wherein the external and internal cutting members of the first cutting unit are in the disconnected condition.

(5) FIG. 4 shows said first cutting unit in a cross-section parallel to, and containing the rotation axis of, the first cutting unit, and wherein the external and internal cutting members of the first cutting unit are in the interconnected condition.

(6) FIG. 5 shows an example of a further embodiment of a cutting unit according to the invention, hereinafter also referred to as (the) second cutting unit, for use in an example of a second embodiment of a shaving head according to the invention, wherein said second cutting unit is shown in a cross-section parallel to, and containing the rotation axis of, the second cutting unit, and wherein the external and internal cutting members of the second cutting unit are in the interconnected condition.

(7) FIG. 6 shows an example of an embodiment of a part of a third embodiment of a shaving head according to the invention, which shaving head comprises two identical cutting units, hereinafter also referred to as (the) third cutting units, wherein said part of the shaving head is shown in a cross-section parallel to, and containing the two respective rotation axes of, the two respective third cutting units, and wherein the external and internal cutting members of the two third cutting units are in the interconnected condition.

(8) The reference signs used in the abovementioned FIGS. 1-6 refer to the abovementioned parts and aspects of the invention, as well as to related parts and aspects, in the following manner. 1 shaving device 2 shaving device main body 3 shaving head 4 shaving head driving body 5; 305 shaving head cutting body 6, 6A, 6B drive shaft 7, 7A, 7B; 207; . . . 307, 307A cutting unit 8; 308 frame of shaving head cutting body 10; 210; 310, . . . 310A rotation axis 11; 211; 311, . . . 311A external cutting member 12; 212; 312, . . . 312A internal cutting member 14 skin supporting member 15 fixation ring for external cutting member 11 16 shaving surface of external cutting member 11 20 play 21; 221; 321, . . . 321A first central portion 22; 222; 322, . . . 322A second central portion 230; 330 magnet 240 magnetic field

DETAILED DESCRIPTION OF THE EMBODIMENTS

(9) Reference is first made to FIGS. 1-4, which show the shaving device 1 based on the first embodiment of the shaving head.

(10) FIG. 1 shows that the shaving device 1 comprises the shaving device main body 2 and the shaving head 3 being connected thereto.

(11) FIG. 2 shows that the shaving head 3 can be taken apart into the shaving head driving body 4 and the shaving head cutting body 5. The shaving head cutting body 5 has the frame 8, to which the three identical first cutting units 7, 7A, 7B of the shaving head 3 are connected. The shaving head driving body 4 has the three driving shafts 6, 6A, 6B for driving the three internal cutting members 12 of the three cutting units 7, 7A, 7B, respectively.

(12) FIG. 3 shows that the first cutting unit 7 comprises the external cutting member 11 and the internal cutting member 12. In operation of the shaving head 3, the shown skin supporting member 14 of the shaving head cutting body 5 is suspended relative to the frame 8 of the shaving head cutting body 5, while at the same time the external cutting member 11 is connected relative to the skin supporting member 14 via the shown fixation ring 15. The external cutting member 11 has the shaving surface 16, which is interrupted by an apertured structure for allowing hairs to pass.

(13) FIG. 4 shows the first cutting unit 7 in the interconnected condition of the external and internal cutting members 11, 12. In FIG. 4 it is seen that the first central portion 21 of the external cutting member 11 comprises the first snap connection structure 31, while the second central portion 22 of the internal cutting member 12 comprises the second snap connection structure 32. It is also seen that the first snap connection structure 31 and the second snap connection structure 32 provide radial bearing support, i.e. bearing support in a radial direction relative to the rotation axis 10, for the rotative movement of the internal cutting member 12 relative to the external cutting member 11 about the rotation axis 10. FIG. 4 furthermore illustrates that the first snap connection structure 31 and the second snap connection structure 32 allow the abovementioned amount of play 20 in respect of translational movement of the internal cutting member 12 relative to the external cutting member 11 in a direction parallel to the rotation axis 10.

(14) In the shown example, the first snap connection structure 31 includes a first radial extension 34 and a bearing stud 38 extending from the first radial extension 34, wherein a free end 35 of the bearing stud 38 has a locally increased diameter, while the second snap connection structure 32 defines a cylindrical recess 39, whose entry opening has a locally decreased diameter provided by a second radial extension 36 extending radially from a circumferential wall 37 of the second snap connection structure 32, while allowing the play 20. In general, the bearing surfaces of the rotative movement between the external and internal cutting members may, amongst others, be formed with such a locally decreased diameter surface of the entry opening of the cylindrical recess and/or such a locally increased diameter surface of the free end of the bearing stud and/or with any other surfaces of the external and internal cutting members.

(15) Generally, the first snap connection structure and/or the second snap connection structure may for example be made of a resilient material. In the shown example, the structure defining the cylindrical recess 39 may for example be made of a resilient plastic material.

(16) The snap connection is preferably designed in such a manner that said holding forces in the first place are sufficient for the internal cutting members to remain in the external cutting members at least when the shaving head 3 is being taken apart from the situation as shown in FIG. 1 into the situation of FIG. 2. In the second place, to keep each internal cutting member in the external cutting member after the shaving head cutting body 5 has been separated from the shaving head driving body 4, said holding forces should preferably be sufficient to carry several times the mass of an internal cutting member (which usually is not much more than 1 g). All in all, the snap connection is preferably designed in such a manner that in the situation of FIG. 2 the manual pulling force required to remove an internal cutting member from an external cutting member will be in the order of magnitude of less than about 20 gf. When inserting an internal cutting member back into an external cutting member after a cleaning step, a gentle push will cause the internal cutting member to snap into place again.

(17) Reference is now made to FIG. 5, which shows the second cutting unit 207 for use in the abovementioned second embodiment of a shaving head according to the invention. The second cutting unit 207 comprises the external cutting member 211 and the internal cutting member 212. It is seen that the first central portion 221 and the second central portion 222 are mutually co-operating portions providing radial bearing support for the rotative movement about the rotation axis 210.

(18) Furthermore it is seen that, in the shown example, the magnet 230 is associated with, and arranged in, the second central portion 222 for providing the abovementioned magnetic attraction between the first central portion 221 and the second central portion 222. In the shown example, the first central portion 221 comprises magnetizable material.

(19) In FIG. 5, the magnetic axis of the magnet 230 has been indicated by means of the depicted two-way arrow, while the corresponding magnetic field of the magnet 230 has been indicated by means of the magnetic field lines 240. Hence, the magnet 230 is placed so as to have its magnetic axis aligned with the rotation axis 210. In the shown example, the magnetic field thus is maximally coupled with the bearing stud of the first central portion 221. Usually, such a bearing stud contains a relatively large proportion of the material of the external cutting member, as a result of which the placement of the magnet 230, as shown, is very favourable.

(20) A practical shape for the magnet used is a cylindrical shape having a diameter of between 2 and 3 mm and a height of between 1 and 3 mm. The force-density requirements are modest, so a relatively low-cost grade of neodymium magnet is already sufficient.

(21) Reference is now made to FIG. 6, which shows a cutting body 305 of the abovementioned third embodiment of a shaving head according to the invention. This shaving head cutting body 305 comprises the two third cutting units 307 and 307A, which are connected to the frame 308 of the shaving head cutting body 305. The third cutting unit 307 comprises the external cutting member 311 and the internal cutting member 312. It is seen that the first central portion 321 and the second central portion 322 are mutually co-operating portions providing radial bearing support for the rotative movement about the rotation axis 310. Similarly, the third cutting unit 307A comprises the external cutting member 311A and the internal cutting member 312A, while the first central portion 321A and the second central portion 322A are mutually co-operating portions providing radial bearing support for the rotative movement about the rotation axis 310A.

(22) Furthermore, it is seen that, in the shown example, the magnet 330 is associated with the shaving head and arranged in the shaving head so as to be remote from the first central portions 321 and 321A and from the second central portions 322 and 322A for magnetically influencing these first central portions and these second central portions for providing the abovementioned magnetic attraction between the first central portion 321 and the second central portion 322, as well as for simultaneously providing the abovementioned magnetic attraction between the first central portion 321A and the second central portion 322A.

(23) In FIG. 6, the magnetic axis of the magnet 330 has been indicated by means of the depicted two-way arrow. In the shown example, each one of the first central portions 321, 321A and the second central portions 322, 322A comprises magnetizable material.

(24) While the invention has been described and illustrated in detail in the foregoing description and in the figures, such description and illustration are to be considered exemplary and/or illustrative and not restrictive; the invention is not limited to the disclosed embodiments.

(25) 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. 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. A single processor or other unit may fulfill the functions of several items recited in the claims. For the purpose of clarity and a concise description, features are disclosed herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the invention may include embodiments having combinations of all or some of the features disclosed. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures can not be used to advantage.

(26) Any reference signs in the claims should not be construed as limiting the scope.