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(11) | EP 0 408 038 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | A depilatory device |
| (57) The present invention provides a depilatory device comprising a housing (1); a first
rotary element (3) mounted with respect to said housing (1) for free rotational movement
about an axis (5) thereof; a second rotary element (10) mounted with respect to said
housing (1) so as to be rotatable about said axis (5); substantially circular end
surfaces (4, 11) of said elements (3, 10); and a drive motor (17) mounted in said
housing (1) and coupled to said second element (10) for rotating it about said axis
(5) and axially displacing it with respect to said first element (3) so that said
end surfaces (4, 11) move towards and away from each other; the arrangement being
such that hair interposed between said surfaces are gripped thereby when said surfaces
(4, 11) come closer together and are plucked upon continued rotation of said elements
(3, 10) during the period of closest approach of said surfaces. |
FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION
[0002] Depilatory devices for the removal, by plucking, or unwanted hair, particularly from the arms and legs, have long been known. In this connection, there has in the past been proposed (Swiss Patent No. 268696) to employ a curved coil spring which, when displaced manually along the skin, rotates about its axis with the consequence that the coil windings on the concave side are pressed together whilst those on the convex side are spread apart. The underlying concept of this proposal is that hair which enters the gap between two spread apart windings on the convex side of the spring becomes wedged between these windings when the coil has rotated and the hair thus wedged is plucked out as a result of the manual displacement of the spring along the skin's surface.
[0003] The concept underlying the manually operated device disclosed in the Swiss patent as incorporated in an electrically powered depilatory device as disclosed in U.S. Patent No. 4,524,772. In a further proposal for an electrically powered depilatory device (U.S. Patent No. 4,726,375) the manually or powered rotatable spring was replaced by a curved flexible rod formed with slits in its surface such that, in the convex portion of the rod the slits are spread apart, whilst in the concave portion of the rod the slits are pressed together.
[0004] In the case of such known depilatory devices, it has been found in practice that they are largely ineffective in removing hair of less than a minimum height. Furthermore, it has been found that the use of such devices is in many cases accompanied by a significant degree of discomfort or even pain.
BRIEF DESCRIPTION OF THE INVENTION
[0006] According to the present invention there is provided a depilatory device comprising a housing; a first rotary element mounted with respect to said housing for free rotational movement about an axis thereof; a second rotary element mounted with respect to said housing so as to be rotatable about said axis; substantially circular end surfaces of said elements; and a drive motor mounted in said housing and coupled to said second element for rotating it about said axis and axially displacing it with respect to said first element so that said end surfaces move towards and away from each other; the arrangement being such that hair interposed between said surfaces are gripped thereby when said surfaces come closer together and are plucked upon continued rotation of said elements during the period of closest approach of said surfaces.
[0007] Preferably the drive motor is coupled to the second element via a drive roller which functionally engages a circular cam surface secured to the second element and coaxial therewith. Preferably said cam surface comprises symmetrically located inclined portions bridged by a central portion of uniform height.
[0008] In accordance with one embodiment of the present invention two pairs of said elements are mounted at opposite ends of a common axle, said end surfaces being constituted by juxtaposed edges of the constituent elements of each pair.
[0009] In use, the displacement of the device over and in contact with a hair growing skin surface, and in any direction, results in the hair in the path of the device entering into a housing head between the end surfaces of the rotary elements. The driven displacement of the second rotary element results in the surfaces coming together so that the hair becomes trapped between them and with the continued rotation of the second element when the surfaces are at their closest results in the trapped hair being effectively plucked. In view of the circular disposition of the end surfaces, hair can enter between them in any direction of motion of the device.
BRIEF SUMMARY OF THE DRAWINGS
[0010] Various embodiments of a depilatory device in accordance with the present invention will now be described by way of example and with reference to the accompanying drawings, in which:
Fig. 1 is a longitudinally sectioned elevation of a first form of depilatory device in accordance with the invention with the constituent rotary elements thereof in a first relative position;
Fig. 2 is a partially sectioned side elevation of the device shown in Fig. 1 with the rotary elements thereof in a second mutual position;
Fig. 3 is a partially sectioned view of a partial side elevation of a modified form of depilatory device in accordance with the invention;
Fig. 4 shows a modification of a rotary element forming part of the devices shown in Figs. 1 and 2;
Figs. 5A, 5B and 5C are schematic representations of the device shown in Fig. 3 illustrating the trapping and plucking of the hair;
Fig. 6 is a partially sectioned view of a partial side elevation of a further modified form of depilatory device in accordance with the invention; and
Fig. 7 is a partially sectioned side elevation of a still further form of depilatory device in accordance with the present invention.
[0011] As seen in Figs. 1 and 2 of the drawings the device comprises a cylindrical housing 1 having a projecting head 2. A first rotary member 3 having a conically tapering end surface 4 is mounted on an axle 5 about which it is freely rotatable, the end of the axle 5 remote from the rotary member 3 is screw mounted within the head 2. The axle 5 is formed at its end adjacent the rotary member 3 with a slotted head 6 which is located within a central bore 7 formed in the rotary member 3. A compression spring 8 has a lowermost end bearing against the slotted head 6 and an uppermost end bears against an inwardly directed shoulder 9 of the rotary element 4.
[0012] A second rotary element 10 is of generally cylindrical shape and is formed with a lower bevelled tapering edge constituting an end surface 11 of the rotary element 10. The rotary element 10 is formed with an upper surface 12 having a centrally upwardly extending boss 13 through which extends the axle 5 whereby the rotary element 10 is rotatable with respect to the axis 5. Formed on the upper surface 12 is a circular rack 14 which constitutes a cam surface having a pair of symmetrically located inclined portions 15a and 15b bridged by a portion 15c of substantially uniform height.
[0013] A compression spring 16 surrounds the axle 5 and bears at its lower end on the rotary member 4 and at its upper end on the upper surface 12 of the rotary member 10.
[0014] Thus, the function of the compression spring 8 is to bias the circular surfaces 4 and 11 together whilst the function of the compression spring 16 is to bias the rotary members 3 and 10 apart. The degree of biasing exerted by the compression spring 8 can be readily adjusted by turning the slotted screw head 6.
[0015] A drive motor 17 is located within the housing 1 and is coupled via a drive axle 18 which extends into the head portion 2 to a drive pinion 19 which engages the circular rack 14.
[0016] In accordance with the modification shown in Fig. 3 of the drawings the circular base edge 21 of the circular element 3 is provided with peripheral serrations or portions of reduced thickness 22.
[0017] In use the drive imparted by the motor 17 to the rotary element 10 causes the latter to rotate and at the same time imparts to the rotary element 10 an axial movement directed so as to bring the surfaces 11 and 4 closer together. When these surfaces have reached their maximum approach the rotary element 10 will have rotated into the position shown in Fig. 2 of the drawings. In this position the pinion 19 has still not reached the bridging portion 15c of the cam surface 15 and the combined rotatin of the pinion 19 until it reaches this bridging portion 15 results in the downward displacement of both the rotary elements 3 and 10 towards the skin. The force with which the surfaces 4 and 11 abut against each other and in consequence the clamping force exerted on interposed hairs, can be adjusted by suitable rotation of the slotted head 6. In view of the extended length of the bridging portion 15c it is ensured that the continued rotational drive imparted to the rotary member 10 when the pinion 19 engages the bridging portion 15c rotates the rotary element 10 when it is in its position of closest approach to the rotary element 3.
[0018] In the modified device shown in Fig. 3 of the drawins a drive roller 19′ formed of a resiliently distortable material (e.g. rubber) functionally engages a cam surface 15′ having portions 15a′, 15b′ and 15c′ similar to those described above. In the present case the resilient compression of the drive roller 19′ when it approaches the bulging portion 15c′ is effective in exerting the same biasing effect on the component rotary elements 3 and 10 as is exerted by the compression spring 8 in the embodiment shown in Figs. 1 and 2 of the drawings.
[0019] By using the modified rotary element 10′ shown in Fig. 4 of the drawings with its serrations 22 constituted by successive reduced width portions of the periphery, it can be ensured that plucking is effective up to and including a minimum height of the hair involved.
[0020] Reference will now be made to Figs. 5a, 5b and 5c of the drawings which illustrate schematically the trapping and plucking of hair 25 extending from a skin surface 26. As seen in Fig. 5a of the drawings with the pinion 19 engaging the lowermost position of the cam surface 15a, the juxtaposed surfaces of the rotary elements are furthest apart and in this condition hair 25 can freely enter the space between these juxtaposed surfaces.
[0021] As seen in Fig. 5b of the drawings, when the uppermost portion of the cam surface 15a has engaged the pinion 19, the hair 25 becomes progressively trapped between the circular end surfaces of the rotary elements. This trapping is completed in the position as shown in Fig. 5c of the drawings wherein the bridging portion 15c becomes engaged by the pinion 19. With the hair 25 thus trapped the continued rotation of the rotary element 10 with the bridging portion 15c engaged by the pinion 19 results in the progressive plucking of the hair from the skin.
[0022] It will be readily seen that the device is effective in engaging, trapping and plucking hair in any direction of movement of the device with respect to the skin and this in view of the circular clamping surfaces which are employed.
[0023] Whilst the compression spring 16 is effective in moving the rotary elements 3 and 10 apart, when the pinion 19 engages the downwardly directed surface 15b, as explained above, the compression spring 8 is effected in pressing the parts together by a degree which can be readily varied in accordance with choice by rotation of the slotted head 6. Thus, the degree of clamping of the circular end surfaces together can be readily varied.
[0024] In the modification shown in Fig. 6 of the drawings the rotary elements 3 and 10 of the embodiment shown in Figs. 1 and 2 are replaced by interfitting conical rotary elements 31 and 32 having extended conical tapering circular surfaces 33 and 34 between which the hairs are trapped. Otherwise the construction and operation of the modified device shown in Fig. 6 of the drawings are similar to the operation and construction of the device shown in Figs. 1 and 2 of the drawings.
[0025] Reference will now be made to Fig. 7 of the drawings which illustrates a modified depilatory device in accordance with the present invention. As seen in the drawings two rotary element pairs 41a and 41b are respectively mounted about an axis 42 which extends transversely with respect to a housing 43, the rotary element pairs 41a and 41b being located within and extending from a head 44 of the device. The rotary element pairs 41a and 41b comprise respectively a pair of conically shaped rotary elements 45a, 46a and 45b, 46b.
[0026] The elements 45a and 45b are freely rotatable on the axis 42 whilst the elements 46a and 46b have rack cam surfaces thereof 47a, 47b which are engaged by a rotary pinion 48 coupled to a drive motor (not shown) located within housing 43.
[0027] The component rotary elements 45a, 46a and 45b, 46b are of oppositely directed conicity and the juxtaposed edges thereof constitute the respective circular end surfaces in accordance with the invention.
[0028] The device is furthermore provided with compression springs 51a and 51b which serve to bias the respective constituent rotary elements of each pair towards each other. Compression springs 52a and 52b which surround the common axle 42 serve to bias the constituent rotary elements of the rotary element pairs apart.
[0029] As in the previously described embodiments, the drive imparted to the rotary elements 46a and 46b gives rise to the rotation of the elements and also causes these elements to move towards the elements 45a and 45b. In view of the cam nature of the racks 47a and 47b (similar to the cam surfaces described with reference to the preceding embodiments) this axial movement towards each other of the juxtaposed edge surfaces of the component rotary elements continues until they have reached a position of maximum approach (see the rotary element pair 41a) at which stage the continued rotation of the rotary element 46a takes place for a period of time with the juxtaposed circular surfaces in substantial abutment.
[0030] In use and with a device as shown in Fig. 7 of the drawings where it is moved along the skin, hair becomes interposed between the spaced apart circular edges of the constituent rotary elements but when these spaced apart edges have moved together the hair becomes trapped and the continued rotation of the rotary elements 46a and 46b with the hair so trapped results in the effective plucking of the hair.
1. A depilatory device comprising a housing; a first rotary element mounted with respect
to said housing for free rotational movement about an axis thereof; a second rotary
element mounted with respect to said housing so as to be rotatable about said axis;
substantially circular end surfaces of said elements; and a drive motor mounted in
said housing and coupled to said second element for rotating it about said axis and
axially displacing it will respect to said first element so that said end surfaces
move towards and away from each other; the arrangement being such that hair interposed
between said surfaces are gripped thereby when said surfaces come closer together
and are plucked upon continued rotation of said elements during the period of closest
approach of said surfaces.
2. A depilatory device according to Claim 1 wherein said drive motor is coupled to
said second element via a drive roller which functionally engages a circular cam surface
secured to said second element and coaxial therewith.
3. A depilatory device according to claim 2 wherein said drive roller is formed of
a resiliently flexible material.
4. A depilatory device according to claim 2, wherein said drive roller is constituted
by a drive pinion and wherein said circular cam surface constitutes a circular rack
with which said pinion engages.
5. A depilatory device according to any one of claims 2, 3 or 4, wherein said cam
surface comprises symmetrically located inclined portions bridged by a central portion
of uniform height.
6. A depilatory device according to any one of the preceding claims wherein first
spring biasing means serve to bias the elements apart.
7. A depilatory device according to Claim 4 herein second spring biasing means are
provided which serve to exert a limited biasing force on said first element towards
said second element.
8. A depilatory device according to Claim 7 wherein screw means are provided for varying
the degree of bias of said second spring biasing means.
9. A depilatory device according to any one of the preceding clams wherein said end
surfaces are substantially conical with the end surface of said first element being
located within the end surface of said second element during said period of closest
approach.
10. A depilatory device according to Claim 9 where said second element is of conical
shape.
11. A depilatory device according to Claim 9 wherein both said elements are of conical
shape.
12. A depilatory device according to any one of the preceding claims wherein two pairs
of said elements are mounted on opposite ends of a common axle and wherein said inserts
are constituted by juxtaposed edges of the constituent elements of each pair.
13. A depilatory device according to any one of the preceding claims wherein one end
surface of the or each pair of elements is formed with peripheral serrations.
14. A depilatory device as hereinbefore described by way of example and with reference
to the accompanying drawings.