U.S. patent application number 14/051597 was filed with the patent office on 2014-04-17 for epilator.
This patent application is currently assigned to Braun GmbH. The applicant listed for this patent is Braun GmbH. Invention is credited to Luis Burrell-Diez, Frieder Grieshaber, Markus Halm, Bernhard Kraus, Andreas Lennartz, Tarik Mehaddene, Tobias Schwarz.
Application Number | 20140107670 14/051597 |
Document ID | / |
Family ID | 47018070 |
Filed Date | 2014-04-17 |
United States Patent
Application |
20140107670 |
Kind Code |
A1 |
Grieshaber; Frieder ; et
al. |
April 17, 2014 |
Epilator
Abstract
An attachment for an epilator or an epilator having at least a
clamping unit for clamping and plucking hairs that is arranged for
driven movement relative to a housing of the attachment or the
epilator along a hair capture direction is disclosed. The clamping
unit has a first clamping element having a clamping surface and a
hair guiding surface and a second clamping element having a
clamping surface and a hair guiding surface. The first clamping
element and the second clamping element are arranged to be
cyclically first between an open position in which the two clamping
surfaces have a minimal distance such that a gap for receiving
hairs is formed between them and a closed position in which the two
clamping surfaces abut on each other. The two hair guiding surfaces
form a funnel in front of the gap in the open position with respect
to the hair capture direction.
Inventors: |
Grieshaber; Frieder;
(Neu-Anspach, DE) ; Mehaddene; Tarik; (Karben,
DE) ; Kraus; Bernhard; (Braunfels, DE) ;
Burrell-Diez; Luis; (Frankfurt am Main, DE) ;
Lennartz; Andreas; (Kressbronn, DE) ; Schwarz;
Tobias; (Schmitten, DE) ; Halm; Markus;
(Koenigstein, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Braun GmbH |
Kronberg |
|
DE |
|
|
Assignee: |
Braun GmbH
Kronberg
DE
|
Family ID: |
47018070 |
Appl. No.: |
14/051597 |
Filed: |
October 11, 2013 |
Current U.S.
Class: |
606/133 |
Current CPC
Class: |
A45D 26/0038 20130101;
A45D 26/0028 20130101; A45D 26/0023 20130101 |
Class at
Publication: |
606/133 |
International
Class: |
A45D 26/00 20060101
A45D026/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 12, 2012 |
EP |
12188286.4 |
Claims
1. A clamping unit for clamping and plucking hairs for an epilator,
the clamping unit being arranged for driven movement along a hair
capture direction, the clamping unit comprising: a first clamping
element having a clamping section and at least a winged section,
wherein the clamping section has a clamping surface and the winged
section has a guiding surface, which guiding surface angles
outwards away from the clamping surface at least with respect to
the hair capture direction; and a second clamping element having a
clamping section and at least a winged section, wherein the
clamping section has a clamping surface and the winged section has
a guiding surface, which guiding surface angles outwards away from
the clamping surface at least with respect to the hair capture
direction; wherein the clamping unit is arranged for cyclical
movement between an open position in which a gap for receiving
hairs and having a minimum width in a width direction perpendicular
to the hair capture direction extends between the clamping surfaces
of the first clamping element and the second clamping element and a
closed position in which the clamping surfaces of the first
clamping element and the second clamping element abut on each other
at least along a clamping line; and wherein the guiding surface of
the first clamping element defines a first side of a funnel for
guiding hairs towards the gap and the guiding surface of the second
clamping element defines a second side of the funnel, wherein at
least one of the first or the second clamping element comprises a
hair guiding surface that has a length extension of ranging between
1.5 mm to 7 mm.
2. The clamping unit in accordance with claim 1, wherein at least
one of the first or the second clamping element comprises a hair
guiding surface that has a length extension of ranging between 2 mm
to 6 mm.
3. The clamping unit in accordance with claim 1, wherein a length
extension of the clamping sections along which hair is able to be
clamped is equal to 1.05 times to 1.6 times a length extension of
the hair guiding surface of one of the first or second clamping
elements.
4. The clamping unit in accordance with claim 1, wherein the total
effective width in a direction perpendicular to the open and
closure movement direction over which the clamping unit catches
hairs is between 2 mm to 7 mm which is the sum of the widths of
both adjacent winged sections within the clamping unit and of the
gap width between both clamping sections in its open position or
which is the maximum opening width of the funnel in the clamping
units open position.
5. The clamping unit in accordance with claim 1, wherein either the
widths of both adjacent winged sections within the clamping unit or
the maximum opening width of the funnel in the clamping units
closed position is at least 2 times larger than the width of the
gap between both adjacent clamping sections in its open
position.
6. The clamping unit in accordance with claim 1, wherein either the
widths of both adjacent winged sections within the clamping unit or
the maximum opening width of the funnel in the clamping units
closed position is at least 3 times larger than the width of the
gap between both adjacent clamping sections in its open
position.
7. The clamping unit in accordance with claim 1, wherein a radial
outer skin contact surface of the clamping unit is part of a
surface of an imaginary enveloping cylinder.
8. The clamping unit in accordance with claim 7, wherein the winged
section of at least one of the first or the second clamping element
comprises said hair guiding surface and said adjacent outer skin
contact surface and wherein both the hair guiding surface and the
outer skin contact surface are connected by a curved edge portion
and wherein the radius of the curved edge portion ranges between
0.01 mm to 0.5 mm.
9. The clamping unit in accordance with claim 7, wherein the radial
outer skin contact surface of the clamping unit comprises a
discrete start and end point covering an angular extension of less
than 90 degrees.
10. The clamping unit in accordance with claim 1, wherein at least
one wing section of one of the first or second clamping element is
curved and comprises an area that lie on the surface of an
imaginary enveloping cylinder.
11. The clamping unit in accordance with claim 1, wherein the first
clamping element is moveable in a direction perpendicular to the
hair capture direction and wherein the second clamping element is
fixed with respect to a direction perpendicular to the hair capture
direction.
12. The clamping unit in accordance with claim 11, wherein the
width of the hair guiding surface of the second clamping element
measured in a width direction perpendicular to the hair capture
direction is larger than the respective width of the hair guiding
surface of the first clamping element.
13. The clamping unit in accordance with claim 11, wherein the
width of the hair guiding surface of the second clamping element is
about as large as the sum of the width of the hair guiding surface
of the first clamping element and the width of the gap in the open
position.
14. The clamping unit in accordance with claim 1, wherein the angle
with which the guiding surface of the winged section of the first
clamping element angles away from the respective clamping surface
is smaller than the angle with which the guiding surface of the
winged section of the second clamping element angles away from the
respective clamping surface.
15. The clamping unit in accordance with claim 1, wherein the
guiding surface has a three-dimensional shape and wherein the
guiding surface is inclined in two different directions.
16. The clamping unit in accordance with claim 1, wherein the
guiding surface comprises or is a plane area.
17. The clamping unit in accordance with claim 1, wherein the
guiding surface comprises or is a curved area.
18. An attachment for an epilator comprising a clamping unit in
accordance with claim 1.
19. An epilator comprising a clamping unit in accordance with claim
1.
20. A clamping element for a clamping unit of an epilator,
comprising: a clamping section comprising a planar clamping surface
for clamping hair and a winged section comprising a planar guiding
surface for catching hair, said guiding surface angles away from
the clamping surface and wherein the winged section comprises an
outer skin contact surface which is adjacent to and angled to the
guiding surface and said outer skin contact surface is provided as
a curved surface.
Description
FIELD OF THE INVENTION
[0001] The present invention is concerned with an attachment for an
epilator and an epilator.
BACKGROUND OF THE INVENTION
[0002] It is known that epilators may comprise a clamping cylinder
on which clamping units comprising two clamping elements are
arranged. During operation, the clamping cylinder is driven into
rotation around its cylinder axis. The clamping units are arranged
to be cyclically moved between an open position in which a gap
extends between the two clamping elements into which gap hairs can
enter and a closed position in which the two clamping element abut
on each other at least along a clamping line such that hairs that
are clamped in between the clamping elements are plucked from the
user's skin when the clamping unit continues to rotate on the
clamping cylinder while being in the closed position. EP 1 796 501
B1 generally describes a clamping cylinder having a plurality of
clamping units.
[0003] It is a general desire to increase the efficiency of
epilators, i.e. to increase the number of hairs that are clamped
and plucked.
[0004] It is hence an object of the present disclosure to provide
an attachment for an epilator and an epilator having an increased
clamping and plucking efficiency over the known devices.
SUMMARY OF THE INVENTION
[0005] In accordance with one aspect there is provided an
attachment for an epilator or an epilator comprising at least a
clamping unit for clamping and plucking hairs, the clamping unit
being arranged for driven movement along a hair capture direction,
the clamping unit comprising a moveable clamping element having a
clamping section and at least a winged section, wherein the
clamping section has a clamping surface and the winged section has
a guiding surface, which guiding surface angles outwards away from
the clamping surface at least with respect to the hair capture
direction; and a fixed clamping element having a clamping section
and at least a winged section, wherein the clamping section has a
clamping surface and the winged section has a guiding surface,
which guiding surface angles outwards away from the clamping
surface at least with respect to the hair capture direction;
wherein the clamping unit is arranged for cyclical movement between
an open position in which a gap for receiving hairs and having a
minimum width in a width direction perpendicular to the hair
capture direction extends between the clamping surfaces of the
moveable clamping element and the fixed clamping element and a
closed position in which the clamping surfaces of the moveable
clamping element and the fixed clamping element abut on each other
at least along a clamping line; and wherein the guiding surface of
the moveable clamping element defines a first side of a funnel for
guiding hairs towards the gap and the guiding surface of the fixed
clamping element defines a second side of the funnel, wherein at
least one of the first or the second clamping element comprises a
hair guiding surface that has a length extension of ranging between
1.5 mm to 7 mm. Thus the funnel structure created by such long
guiding surfaces is effective to grasp hair over a longer time as
the clamping cylinder may continue to rotate and the funnel still
grasps hair. The prior art devices have so far focused on using the
limited space on the clamping cylinder by increasing the number of
clamping units on one cylinder or increasing the speed of rotation
of the clamping cylinder and trying to increase hair epilating
efficacy in that way. It has been found that a larger extension of
funnels with hair guiding surfaces being as long as between 1.5 and
7 mm is superior in epilating efficiency although less space is
left on the clamping cylinder for clamping sections or further
clamping units.
[0006] In accordance with one aspect it is provided that at least
one of the first or the second clamping element comprises a hair
guiding surface that has a length extension of ranging between 2 mm
to 6 mm. This is a further optimized range that balances well the
space utilized for the hair guiding surfaces on the clamping
cylinder relative to that space that is left over for additional
clamping units around the perimeter of the clamping cylinder.
[0007] In accordance with one aspect it is provided that a length
extension of the clamping section along which hair is able to be
clamped is equal to 1.05 times to 1.6 times a length extension of
the hair guiding surface of one of the first or second clamping
elements. This defines a new balance between the circumferential
extension used on the clamping cylinder for the actual hair
plucking clamping section relative to the extension around the
perimeter of the clamping cylinder used for the hair guiding
surfaces provided on the winged sections. If the length extension
along the hair capture direction of the clamping section is e.g. 6
mm then the guiding surface has a minimum extension in the same
direction of 3.75 mm and a maximum extension which is almost the
same as that of the clamping section, i.e. 5.7 mm in accordance
with the above defined range. This allows up to almost the same
amount of rotation of the clamping cylinder used for proper
grasping hair along the funnel as for actual hair plucking in the
clamping section.
[0008] In accordance with one aspect it is provided that the total
effective width in a direction perpendicular to the open and
closure movement direction over which the clamping unit catches
hairs is between 2 mm to 7 mm which is the sum of the widths of
both adjacent winged sections within the clamping unit and of the
gap width between both clamping sections in its open position (or
the later sum of widths is understood to be the same as which is
the maximum opening width of the funnel in the clamping units open
position). Thus a substantial portion of the lateral extension of
the clamping cylinder is used for providing a funnel width of
between 2 to 7 mm. This again allows less clamping units being
located onto the clamping cylinder also in the lateral direction.
It revealed that hair plucking efficacy is even superior due to
effective hair grasping although less clamping sections can be
provided over all.
[0009] In accordance with one aspect it is provided that either the
widths of both adjacent winged sections within the clamping unit or
the maximum opening width of the funnel in the clamping units
closed position is at least 2 times larger than the width of the
gap between both adjacent clamping sections in its open position. A
much larger funnel width than a gap width between the clamping
sections allows to increase the plucking efficacy additionally.
[0010] In accordance with one aspect it is provided that either the
widths of both adjacent winged sections within the clamping unit or
the maximum opening width of the funnel in the clamping units
closed position is at least 3 times larger than the width of the
gap between both adjacent clamping sections in its open
position.
[0011] In accordance with one aspect it is provided that a radial
outer skin contact surface of the clamping unit is part of a
surface of an imaginary enveloping cylinder. This allows smooth
operation and pressing of the device against the skin without small
up and downs and allows more catching of hair along the winged
section of the clamping unit.
[0012] In accordance with one aspect it is provided that the winged
section of at least one of the first or the second clamping element
comprises said hair guiding surface and said adjacent outer skin
contact surface and wherein both the hair guiding surface and the
outer skin contact surface are connected by a curved edge portion
and wherein the radius of the curved edge portion ranges between
0.01 mm to 0.5 mm. This narrow edge between the skin contact
surface and the guiding surface prevents that hair may glide along
an edge portion of the winged section without being effectively
catch in the funnel and then introduced into the plucking gap.
[0013] In accordance with one aspect it is provided that the radial
outer skin contact surface of the clamping unit comprises a
discrete start and end point covering an angular extension of less
than 90 degrees. Thus the clamping unit does not extend all over
the perimeter over 360 degrees at clamping cylinder. By avoiding a
full disc shape design of the clamping unit but providing only
discrete 90 degrees or less sector space requiring clamping units
the clamping unity can be aligned still laterally close but
circumferentially laterally shifted.
[0014] In accordance with one aspect it is provided that at least
one wing section of one of the first or second clamping element is
curved and comprises an area that lie on the surface of an
imaginary enveloping cylinder. This allows smooth operation and
pressing of the device against the skin without small up and downs
and allows more catching of hair along the winged section of the
clamping unit.
[0015] In accordance with one aspect it is provided that the first
clamping element is moveable in a direction perpendicular to the
hair capture direction and wherein the second clamping element is
fixed with respect to a direction perpendicular to the hair capture
direction.
[0016] In accordance with one aspect it is provided that the width
of the hair guiding surface of the second clamping element measured
in a width direction perpendicular to the hair capture direction is
larger than the respective width of the hair guiding surface of the
first clamping element. Thus this avoids that hair is lost at the
hair guiding surface along its closure of the moveable element.
[0017] In accordance with one aspect it is provided that the width
of the hair guiding surface of the second clamping element is about
as large as the sum of the width of the hair guiding surface of the
first clamping element and the width of the gap in the open
position. Thus the funnel effect is on both sides of the clamping
unit balanced if the movable clamping element covers a funnel width
including the gap relative to a larger funnel width portion
provided by the fixed clamping element.
[0018] In accordance with one aspect it is provided that the angle
with which the guiding surface of the winged section of the first
clamping element angles away from the respective clamping surface
is smaller than the angle with which the guiding surface of the
winged section of the second clamping element angles away from the
respective clamping surface. This increases the hair grasping
efficacy if the first clamping element is the moveable one and the
second one is fixed relative to the clamping cylinder.
[0019] In accordance with one aspect it is provided that the
guiding surface has a three-dimensional shape and wherein the
guiding surface is inclined in two different directions. Thus hair
can be hold down in the direction to the clamping cylinder lower
surface and is thus grasped more effectively.
[0020] In accordance with one aspect it is provided that the
guiding surface comprises or is a plane area.
[0021] In accordance with one aspect it is provided that the
guiding surface comprises or is a curved area.
[0022] In accordance with one aspect there is provided an
attachment for an epilator comprising a clamping unit in accordance
with at least one of the above features.
[0023] In accordance with one aspect there is provided that an
epilator comprising a clamping unit in accordance with at least one
of the above features.
[0024] In accordance with one aspect there is provided a clamping
element for a clamping unit of an epilator, comprising: a clamping
section comprising a planar clamping surface for clamping hair and
a winged section comprising a planar guiding surface for catching
hair, said guiding surface angles away from the clamping surface
and wherein the winged section comprises an outer skin contact
surface which is adjacent to and angled to the guiding surface and
said outer skin contact surface is provided as a curved surface.
This allows smooth operation and pressing of the device against the
skin without small up and downs and allows more catching of hair
along the winged section of the clamping unit.
[0025] In accordance with one aspect there is provided an
attachment for an epilator or an epilator, optionally in accordance
with any other aspect of the present disclosure, comprising at
least a clamping unit comprising at least a moveable clamping
element having a clamping section having a clamping surface and a
winged section having a guiding surface that angles outwardly away
from the clamping surface, wherein the winged section is
pre-stressed such that it angles away from the clamping section in
an unconstrained situation at a predetermined angle and is flexibly
or pivotably arranged such that the angle with which the winged
section angles away from the clamping element can be modified by
applying a force onto the winged section in a direction that acts
against the pre-stress force.
[0026] In accordance with one aspect there is provided an
attachment for an epilator or an epilator, optionally in accordance
with any other aspect of the present disclosure, comprising at
least a clamping unit, the clamping unit having a movable clamping
element having a clamping surface and a second clamping element
having a clamping surface that are arranged to be cyclically
movable with a closure velocity between an open position in which a
gap having a minimal width extends between the two clamping
surfaces and a closed position in which the clamping surfaces abut
on each other over a length, which clamping unit is arranged to be
movable at a movement velocity relative to a housing of the
epilator, wherein the effective hair catching area of the clamping
unit in relation to the closure time is at least 3500 mm.sup.2/s,
in particular wherein the effective hair catching area of the
clamping unit in relation to the closure time is at least 4000
mm.sup.2/s, further in particular wherein the effective hair
catching area of the clamping unit in relation to the closure time
is at least 4500 mm.sup.2/s.
[0027] In accordance with one aspect there is provided an
attachment for an epilator or an epilator comprising at least a
clamping unit for clamping and plucking hairs that is arranged for
driven movement relative to a housing of the epilator along a hair
capture direction, the clamping unit comprising a moveable clamping
element having a clamping surface and a hair guiding surface and a
fixed clamping element having a clamping surface and a hair guiding
surface, wherein the moveable clamping element and the fixed
clamping element are arranged to be cyclically moveable between an
open position in which the two clamping surfaces have a minimal
distance such that a gap for receiving hairs is formed between them
and a closed position in which the two clamping surfaces abut on
each other, wherein the two hair guiding surfaces form a funnel in
front of the gap in the open position with respect to the hair
capture direction, which funnel has a width measured in a width
direction perpendicular to the hair capture direction, which funnel
width is given by the sum of the width of the hair guiding surface
of the moveable clamping element, the gap width, and the width of
the hair guiding surface of the fixed clamping element, wherein the
width of the hair guiding surface of the fixed clamping element is
larger than the width of the hair guiding surface of the moveable
clamping element, optionally wherein the width of the hair guiding
surface of the fixed clamping element is about as large as the sum
of the width of the hair guiding surface of the moveable clamping
element and the gap width.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The present disclosure will be further elucidated by a
detailed description of example embodiments and with reference to
figures. In the figures:
[0029] FIG. 1 is a generic depiction of an epilator comprising an
attachment and a housing section;
[0030] FIG. 2 is a depiction of the attachment shown in FIG. 1 in a
detached state;
[0031] FIG. 3A is a depiction of an example embodiment of a
clamping cylinder in accordance with at least one aspect of the
present disclosure;
[0032] FIG. 3B is a depiction of an example embodiment of an
enlarged view of a portion of the clamping cylinder in accordance
with at least one aspect of the present disclosure
[0033] FIG. 4A is a schematic depiction of an example embodiment of
a clamping unit in accordance with at least one aspect of the
present description shown in an open position;
[0034] FIG. 4B is a depiction of the clamping unit shown in FIG. 4A
in a closed position;
[0035] FIG. 5A is a schematic depiction of another example
embodiment of a clamping unit in accordance with at least one
aspect of the present description shown in an open position;
[0036] FIG. 5B is a depiction of the clamping unit shown in FIG. 5A
in a closed position; and
[0037] FIG. 6 is a cross sectional cut though a clamping cylinder,
the cut taken in a plane being perpendicular to the longitudinal
cylinder axis.
DETAILED DESCRIPTION OF THE INVENTION
[0038] An attachment for an epilator or an epilator in accordance
with any aspect of the present disclosure may in particular
comprise a carrier, e.g. a clamping cylinder or a clamping disc, on
which at least one clamping unit is arranged, which clamping unit
comprises two clamping elements, at least one of these clamping
elements being a moveable clamping element and the other clamping
element being either also a moveable clamping element or a fixed
clamping element. The clamping unit forms a discrete portion of the
perimeter of the clamping cylinder that protrudes from the clamping
cylinder. The clamping unit (i.e. the carrier--e.g. a clamping
cylinder) may be arranged for driven movement along a hair capture
direction. Each of the clamping elements has a clamping section
having a clamping surface. The clamping elements of the clamping
unit are arranged to be cyclically moveable between an open
position in which a free gap having a minimal gap width extends
between the clamping surfaces of the clamping elements such that
hairs can be fed into the gap (i.e. the clamping surfaces are
arranged vis-a-vis) and a closed position in which the clamping
surfaces abut on each other at least along a clamping line (as is
explained further below, the clamping surfaces may abut on each
other also in a laminar manner). Hairs that are clamped between the
clamping surfaces in the closed position will eventually be plucked
from the skin when the clamping unit continues to be moved along
the hair capture direction relative to the skin of a user while
being in the closed position. The clamping elements may in
particular each comprise a clamping section on which the clamping
surface is arranged and a winged section that is arranged in front
of the clamping unit with respect to the hair capture direction and
on which a guiding surface is arranged. The winged section angles
outwardly away from the clamping section with respect to the hair
capture direction such that each of the guiding surfaces of the
winged sections of the two clamping elements of the clamping unit
form one side of a funnel for guiding hairs towards the gap
extending between the clamping surfaces while the clamping unit is
in the open position and while the clamping unit is being closed,
i.e. hairs are guided into the narrowing gap by the guiding
surfaces until the gap is closed (i.e. until the gap is so small
that hairs do not feed into the gap anymore). The two such formed
sides of the funnel each have a width that is measured in a width
direction perpendicular to the hair capture direction (wherein the
width direction is also essentially perpendicular to the clamping
surfaces in the closed position), wherein in particular in
accordance with at least one aspect of the present disclosure where
the clamping unit comprises a moveable clamping element and a fixed
clamping element, the width of the guiding surface of the moveable
clamping element is smaller than the width of the guiding surface
of the fixed clamping element. In some embodiments, the width of
the guiding surface of the fixed clamping element may then be
chosen about as large as the sum of the width of the guiding
surface of the moveable clamping element plus the width of the gap
in the open position.
[0039] In some embodiments of an attachment for an epilator or an
epilator in accordance with at least one aspect of the present
disclosure, a plurality of clamping units is arranged on a clamping
cylinder that is arranged for driven movement around its
longitudinal centre axis. Thus the clamping unit is arranged on a
clamping cylinder rotating around an axis of rotation and the
moveable clamping element is moveable in a direction perpendicular
to the hair capture direction or in other words in a direction
parallel with said axis of rotation (which is the same axis as the
clamping cylinder longitudinal centre axis). The width direction is
then parallel to the longitudinal cylinder axis. The clamping units
may then be arranged such that the gaps of the clamping units in
their open positions do not overlap in the longitudinal cylinder
direction, i.e. such that the sum of the widths of all gaps of the
plurality of clamping units covers an effective width of the
clamping cylinder (which is the width over which the clamping
cylinder epilates) by less than 100%, in particular less than 90%,
less than 80%, less than 70% or less than 65%. Thus the sum of all
gaps between the clamping sections of all clamping units is smaller
than the total width of the clamping cylinder. In some embodiments,
where each of the plurality of clamping units has a funnel formed
in front of the clamping unit, the sum of the total widths of all
funnels of all clamping units covers the effective width of the
clamping cylinder by more than 100%, in particular more than 200%,
or more than 300%. Thus a high hair removal efficacy is achieved
although less clamping gaps/clamping units are provided.
[0040] In some embodiments of an attachment for an epilator or an
epilator in accordance with at least one aspect of the present
disclosure, at least one clamping unit comprising two clamping
elements is arranged on a clamping cylinder and the length along
which two clamping elements abut on each other in a closed position
of the clamping unit is in a range of between about 8% to 12% of
the perimeter of an enveloping cylinder of the clamping cylinder,
in particular in a range of between about 8.5% and about 10.5%,
further in particular has a value of about 10%.
[0041] In some embodiments of an attachment for an epilator or an
epilator in accordance with at least one aspect of the present
disclosure, a carrier, e.g. a clamping cylinder or a clamping disc,
has a lower lying surface not intended for contact with the skin of
a user during regular operation, which lower lying surface has a
microscopic or macroscopic texture or has a surface coating or
surface layer of a friction enhancing material that has an enhanced
friction with hair when compared to the friction between the base
material from which the carrier is made and hair. The macroscopic
texture may in particular be realized as ridges extending in
longitudinal cylinder direction, which ridges may have a height in
a range of between about 0.02 mm to about 2.0 mm, in particular of
between about 0.05 mm to 0.5 mm, further in particular a value of
about 0.1 mm. In addition, the circumferential distance between the
ridges may lie in a range of between 0.2 mm to about 2.0 mm. The
microscopic texture may in particular be achieved by a certain
roughness, which may be realized by filling material in the base
material, e.g. glass fibers or ceramic particles.
[0042] In some embodiments of an attachment for an epilator or an
epilator in accordance with at least one aspect of the present
disclosure, at least a clamping unit is arranged on a carrier, e.g.
a clamping cylinder or a clamping disc, which clamping unit has a
clamping element having a clamping section that has a clamping
surface and a winged section that has a guiding surface, which
guiding surfaces angles outwardly away from the clamping surface
(i.e. the winged section angles outwardly away from the clamping
section) and wherein the guiding surface has a three-dimensional
shape, i.e. the guiding surface does not lie in a plane in a
Cartesian coordinate system.
[0043] In some embodiments of an attachment for an epilator or an
epilator in accordance with at least one aspect of the present
disclosure, at least a clamping unit is arranged on a carrier, e.g.
a clamping cylinder or a clamping disc, which clamping unit has a
moveable clamping element having a clamping section and a winged
section, wherein the winged section is flexible or is hinged at the
clamping section and wherein the winged section is under a
pre-stress such that it outwardly angles away from the clamping
section at a preset value in an unconstraint value and wherein the
angle with which the winged section angles away from the clamping
section can be modified (in particular reduced) by a force acting
against the pre-stress. In particular, the force acting against the
pre-stress may be provided by a fixed wall element against which a
free end of the winged section abuts, while the clamping unit is in
an open position and along which fixed wall element the free end of
the winged section will glide at least during a part of the
movement when the moveable clamping element is moved such that the
angle with which the winged section angles away from the clamping
section is modified (in particular is increased).
[0044] FIG. 1 is a depiction of an example embodiment of an
epilator 1 having a detachable attachment 10 and a housing section
20 that can be held in a user's hand. The housing section 20 may
comprise an on/off-switch 21 (which may also be used to switch
between different speed settings) and/or a grip area 22 that may be
made from a (in particular structured) friction-enhanced material,
e.g. a thermoplastic elastomer or a natural rubber. The housing
section may also comprise a drive and/or an energy source (e.g. an
accumulator). In the shown embodiment, the attachment 10 comprises
a clamping cylinder 11 having a plurality of clamping units 12. The
clamping cylinder 11 is arranged for driven movement around its
centre axis A (i.e. the longitudinal cylinder axis) such that the
clamping units 12 move along a hair capture direction D. The
attachment 10 may comprise a detachable cap unit 13 having an
opening 14 through which the clamping cylinder 11 extends for being
brought into contact with a user's skin. The opening 14 defines an
effective width E of the clamping cylinder 11 measured in
longitudinal cylinder direction, which is the width over which the
epilator can clamp and pluck hairs during operation. A user will
typically move the epilator over the skin along a movement
direction M which coincides with the hair capture direction D. As
will be explained in more detail further below, the clamping units
12 each comprise two clamping elements of which at least one
clamping element is arranged to be moveable. The clamping elements
are arranged for cyclical movement between an open position in
which hairs can enter into a gap extending between clamping
surfaces of the clamping elements and a closed position in which
the clamping surfaces abut on each other at least along a clamping
line. As is generally known, hairs that are clamped by the clamping
units in the closed position will be eventually plucked from the
skin when the clamping unit continues to move along the hair
capture direction D while the clamping unit continues being in the
closed position. Patent document EP 1 796 501 B1 generally
describes an epilator having a clamping cylinder with a plurality
of clamping units; the content of said document shall be
incorporated herein by reference.
[0045] While in FIG. 1 and in the below example embodiments, an
epilator or an attachment for an epilator is discussed that has a
clamping cylinder carrying the clamping unit, the clamping unit may
be arranged at any other carrier arranged for being driven along a
hair capture direction. E.g. the clamping unit may be provided at a
disc that is arranged for driven rotation around its centre
axis.
[0046] FIG. 2 shows an example embodiment of an attachment 10 for
an epilator shown in its detached state, which attachment 10 is in
accordance with the attachment discussed with respect to FIG. 1.
While it is here shown that an attachment for an epilator is
detachable, this shall not exclude that the features discussed with
respect to an attachment can also be realized at an epilator not
having a detachable attachment, i.e. where the clamping unit is
arranged at a carrier (e.g. a clamping cylinder) at the
epilator.
[0047] Both Epilator and attachment of FIGS. 1 and 2 comprise a
clamping cylinder with a lower level surface that is provided with
a (non gliding) friction surface 23 which is either made by an
elastomeric coating or an increased surface roughness.
[0048] FIG. 3A shows an example embodiment of a clamping cylinder
30 shown in a perspective view. A plurality of clamping units 31 is
arranged on the clamping cylinder 30. Each clamping unit 31
comprises a fixed clamping element 32 and a moveable clamping
element 33. The fixed clamping elements 32 may be made integral
with the clamping cylinder base material, e.g. the fixed clamping
units may be made from a plastic material and may be manufactured
by a plastic injection molding process together with a part of the
clamping cylinder. As has been mentioned before, the clamping
elements 32, 33 are arranged for cyclic movement between an open
position in which a gap 34 extends between the clamping elements
such that hairs can enter into the gap and a closed position in
which the clamping elements abut on each other and thus clamp hairs
having been in the gap. At least one wing section of one of the
moveable or fixed clamping element comprises an outermost arc
shaped portion. The clamping section of at least one of the
moveable or fixed clamping element comprises also an outermost arc
shaped portion. Thus the clamping elements 32, 33 have outer
surfaces 32A, 33A that essentially lie on the surface of an
enveloping cylinder. The outer surfaces 32A, 33A are intended for
contact with a user's skin during operation. A regular pattern of
ridges 36 extending in longitudinal cylinder direction on a lower
level of the clamping cylinder surface (i.e. on a level of the
clamping cylinder below the enveloping cylinder--see FIG. 6) is
provided in the shown example embodiment. In some embodiments, the
enveloping cylinder may have a diameter of about 19 mm and the
cylinder defined by the lower level surface (i.e. the surface that
is defined by the top parts of the ridges) may have a diameter of
about 17 mm. In some embodiments, the ridges may have a height of
between 0.05 mm to 0.5 mm or e.g. 0.1 mm. The geometry and function
of the ridges (or similar structures) will be explained further
below in more detail, but such structures as the shown ridges serve
to erect hairs that lie close to the skin. The clamping cylinder 30
comprises an axis 39 that may be borne by respective bearings
provided at the attachment so that the clamping cylinder 30 is
enabled to rotate around its central axis C in rotation direction
R. A spring 38 presses the clamping cylinder parts together and
provides the clamping force with which the clamping elements are
pressed together in their closed position. The clamping cylinder 30
may also comprise at least one gear wheel 37 provided for meshing
with a further gear wheel that may be driven during operation,
which further gear wheel may be a part of the housing section.
[0049] While the example embodiment of a clamping cylinder shown in
FIG. 3A has a plurality of clamping elements, it is noted that in
accordance with the present disclosure it is sufficient that a
clamping cylinder has at least one clamping unit. It is also noted
that in case of two or more clamping units, the clamping units may
each be different, e.g. one clamping unit may comprise a fixed and
a moveable clamping element, another clamping unit may comprise two
moveable clamping units. It is also generally noted that all
features shown and discussed with respect to an example embodiment
do not necessarily need to be seen as disclosed only in that
combination but that all features that can be separated without
violating the gist and scope of the present disclosure shall be
considered as being disclosed independently from all other
features. E.g. the ridges provided on the clamping cylinder
discussed in connection with FIG. 3A may not only be an optional
feature but may indeed be considered as an independent aspect of
the present disclosure.
[0050] It is noted that in general an epilation cylinder may be
equipped with a friction enhanced lower level surface, which
friction enhancement (with respect to hairs) may be achieved by
macroscopic structures (e.g. ridges as shown in and discussed with
respect to FIG. 3A) or by microscopic structures (e.g. a certain
roughness) or by a material choice providing an increased friction
with hairs (e.g. keratin filaments) when compared to the plastic
material used for making the clamping cylinder. E.g. the lower
level surface of the clamping cylinder may have a coating of an
artificial rubber. The friction enhancement of a lower level
surface was found to potentially increase the number of hairs that
become erected out of a position where they lie close to the skin.
Hairs lying close to skin still have a certain elevation above the
skin surface. The lower level surface is thus retracted from the
enveloping cylinder by a typical value of between about 0.25 mm to
about 3.0 mm, in particular of between about 0.5 mm to 1.5 mm, in
order to provide a good hair erection effectiveness. With
additional hairs being erect, the efficiency of the epilator is
likely to be increased. Whether the enhanced friction of the lower
level surface of the epilator is provided by microscopic or
macroscopic structures realized in the base material of the
clamping cylinder or by a coating or layer of a different material
covering the lower level surface, this feature is considered as an
independent aspect of the present disclosure, while this feature
may also be combined with all other features of the present
disclosure.
[0051] FIG. 3B shows a portion of a clamping cylinder similar to
that of FIG. 3A. The enlarged view of FIG. 3B illustrates the
ridges 36 which may be in this example provided as grooves
alternating with flattened high portions on a lower level portion
of the clamping cylinder 30. It is a regular repeating pattern that
is injection molded into the surface structure. The ridges 36
extend parallel to the longitudinal cylinder axis C (shown in FIG.
3A).
[0052] FIG. 3B also shows an imaginary enveloping cylinder which
coincides or is parallel with all outer contact surfaces 33A, 32A
of the clamping units. The winged section comprises a sharp radius
41 of between 0.01 mm to 0.5 mm at the edge between the winged
sections guiding surface and the skin contact surface.
[0053] FIG. 4A shows an example embodiment of a schematically drawn
clamping unit 100 shown in an open position, which clamping unit
100 may be arranged on a clamping cylinder as shown in FIG. 3A. The
clamping unit has a moveable clamping element 110 and a fixed
clamping element 120 that are arranged vis-a-vis. The moveable
clamping element 110 may be made from a metal sheet such as a
stainless steel sheet material, while it should not be excluded
that the moveable clamping element may be made from other materials
such as plastic or reinforced plastic. The fixed clamping element
120 may be an integral part of at least a part of a clamping
cylinder and may be made from a plastic material (e.g. via a
plastic injection molding process), in particular from a plastic
material that is reinforced by a filling substance such as glass
fibers or ceramic particles.
[0054] The moveable clamping element 110 has a clamping section 111
and a winged section 112. The clamping section 111 extends in a
length direction L with a length L1 and has a clamping surface 113.
The length direction L coincides with the hair capture direction
(see reference numeral D in FIG. 1) along which the clamping unit
100 will be moved during operation. The fixed clamping element 120
has a clamping section 121 and a winged section 122. The clamping
section 121 extends in a length direction L with a length L1 and
has a clamping surface 123 that faces the clamping surface 113 of
the moveable clamping element 110. The position of the two
oppositely arranged clamping elements 110, 120 coincide in length
direction L so that in a closed position (FIG. 4B), the effective
clamping length is also L1. In the open position as shown in FIG.
4A, a gap 130 extends between the clamping surfaces 113, 123 of the
moveable and fixed clamping elements 110, 120. The gap 130 has in
the open position a minimal gap width W2 in a width direction W
(the width direction W being perpendicular to the length direction
L, i.e. the width direction is perpendicular to the hair capture
direction). As the clamping sections 111, 121 may not necessarily
be parallel to each other in the open position, the minimal gap
width W2 may not be the same over the whole gap extension. The
minimal gap width W2 is sized such that hairs can feed into the
gap. While the diameter of typical human hairs may lie in a range
of 80 micrometer.+-.40 micrometer, the gap width W2 may lie in a
range of between about 0.1 mm to about 2.0 mm, in particular in a
range of between about 0.4 mm to about 1.4 mm. In some embodiments,
the minimal gap width W2 may be about 0.6 mm.
[0055] The winged section 122 of the fixed clamping element 120 has
a guiding surface 124 that outwardly angles away from the clamping
surface 123 of the clamping section 121 with an angle 125 such that
a first side of a funnel is formed on a front side 101 of the
clamping unit 100. The front side 101 of the clamping unit 100 is
the side from which hairs approach the clamping unit 100 during
operation, when the clamping unit 100 is moved along the hair
capture direction that here coincides with the length direction L.
The guiding surface 124 of the winged section 122 extends in length
direction L over a length L2 and in the width direction W over a
width W3. The winged section 112 of the moveable clamping element
110 has a guiding surface 114 that outwardly angles away from the
clamping surface 113 of the clamping section 111 with an angle 115
such that a second side of the funnel is formed. The guiding
surface 114 of the winged section 112 extends in length direction L
over a length L3 and in the width direction W over a width W 1. The
total effective width W4 over which the clamping unit 100 thus may
catch and hence plug hairs is given by the sum of the widths' of
the winged sections 112 and 122 and of the gap width W2,
W4=W1+W2+W3. The total effective width over which the clamping unit
catches hairs may be between 2 mm to 7 mm which is the sum of the
widths' of both adjacent winged sections within a clamping unit and
of the gap width between both clamping sections in its open
position.
[0056] As is generally known, the moveable clamping element 120 may
be spring loaded such that the clamping unit 100 is in the open
position as long as a respective actuator is not forcing the two
clamping elements 110, 120 together.
[0057] During operation, the clamping unit 100 will be moved
relatively to the user's skin such that hairs growing on the skin
will approach the clamping unit 100 from the front side 101 of the
clamping unit 100 and will be guided by the guiding surfaces 114
and 124 into the gap 130, which gap will be closed until the
clamping surfaces 113, 123 are urged together so that hairs in the
gap 130 will then be clamped and will eventually be plugged from
the skin due to the relative movement between the clamping unit 100
and the user's skin. The relative movement between the clamping
unit 100 and the user's skin typically has two components: the
usually faster component is provided by the drive of the epilator
that drives the clamping unit 100 into motion, e.g. by rotating a
clamping cylinder into rotation, and by a usually slower component
that is given by the movement the user introduces by manually
moving the epilator over the skin. The clamping cylinder may be
driven with a number of rotations per minute (rpm) that lie in a
range of between about 500 rpm to about 5000 rpm, in particular in
a range of between about 1000 rpm to about 2500 rpm. In some
embodiments, the clamping cylinder may rotate in a range of between
about 1300 rpm to about 1900 rpm.
[0058] In some embodiments, the width W3 by which the guiding
surface 124 of the fixed clamping element 120 extends in width
direction W may be set to a value that allows hairs that are caught
at the outer edge of the first side of the funnel to become clamped
by the clamping unit. This value may in particular depend on the
typical hair length of hairs that will become epilated and a
typical time period between epilation events. A typical growth
length for hairs growing on human skin is about 0.2 mm per day. A
typical period between epilation events may be 2 weeks, i.e. 14
days, so that the hair has grown 2.8 mm between respective
epilation events. During epilation, some hairs that are not plucked
from the skin typically break about 0.5 mm-1.0 mm below the skin
surface, so that the hair length of the broken hairs above the skin
may roughly be in the range of 1.8 mm to 2.3 mm (hairs that are
plucked together with at least a part of the hair root require a
certain period for growing again as first the hair root needs to be
rebuild). Assuming that a certain length of the hair needs to
extend into the gap of the clamping unit for reliable epilation,
typical values for the width W3 of the guiding surface of the fixed
clamping element may thus lie in a range of between about 0.4 mm to
about 2.0 mm. As the moveable clamping element 110 moves towards
the fixed clamping element 120, the effective width of the second
side of the funnel is determined by the sum of the gap width W2 and
the width W1 of the guiding surface 114 of the moveable clamping
element 110. Thus, a symmetric setting of the funnel widths would
require W1 to be set to W3 minus W2, W1=W3-W2. That means that for
a symmetric guiding efficiency the winged sections may be
asymmetrically realized, e.g. the guiding surface 114 of the winged
section 112 of the moveable clamping element 110 may have a shorter
width W1 in comparison to the width W3 of the guiding surface 124
of the winged section 122 of the fixed clamping element 120. In
other words the fixed clamping unit comprises a winged section that
is longer and/or with broader width extension than the winged
section of the moveable clamping unit.
[0059] In some embodiments, the length L2 of the guiding surface
124 of the winged section 122 of the fixed clamping element 120 may
lie in a range of between about 2 mm and about 8 mm and the
respective width W3 may be in a range of between about 0.5 mm and
about 3.0 mm. In some embodiments, the length L2 may be about 5 mm.
In some embodiments, the width W3 may be about 1.5 mm, which may be
considered a value that nicely considers the above mentioned hair
length of broken hairs after two weeks and thus provides an adapted
high efficiency based on the typical hair length. A larger width W3
may increase efficiency further if hairs are longer (e.g. in case
that a longer period lies between epilation events), but a larger
width w3 also requires more available space on the carrier (e.g.
the clamping cylinder) on which the clamping unit is arranged. In
some embodiments, the length L3 of the guiding surface 114 of the
winged section 112 of the moveable clamping element 110 may be in a
range of between about 0.1 mm and about 4.0 mm and the width W1 may
be in a range of between about 0.1 mm and about 2.0 mm. In some
embodiments, the length L3 may be about 2 mm. In some embodiments,
the width W1 may be about 0.8 mm.
[0060] In some embodiments, the angle 115 between the clamping
surface 113 and the guiding surface 114 of the winged section 112
of the moveable clamping element 110 and/or the angle 125 between
the clamping surface 123 and the guiding surface 124 of the winged
section 122 of the fixed clamping element 120 may lie in a range of
between about 5 degree to about 45 degree, in particular in a range
of between about 10 degree to about 30 degree. In some embodiments,
the respective angles 115, 125 may be different; in particular, the
angle 115 may be larger than the angle 125. In some embodiments,
the angle 115 between the clamping surface 113 and the guiding
surface 114 of the winged section 112 of the moveable clamping
element 110 may be about 22.5 degrees. In some embodiments, the
angle 125 between the clamping surface 123 and the guiding surface
124 of the winged section 122 of the fixed clamping element 120 may
be about 16 degrees.
[0061] In some embodiments, alternatively or additionally the width
W3 by which the guiding surface 124 of the fixed clamping element
120 extends in width direction W is about the same as the sum of
the minimal gap width W2 and of the width W1 of the guiding surface
114 of the winged section 112 of the moveable clamping element 110,
W3.apprxeq.W1+W2, in particular wherein W3 differs by not more than
10% from W2+W1, optionally by not more than 5%, further in
particular where W3 is identical to W1+W2, W3=W1+W2.
[0062] FIG. 4B schematically shows the clamping unit 100 shown in
FIG. 4A in its open position in its closed position. In order to
reach the closed position, the moveable clamping element 110 is
moved generally along a closure direction M as indicated in FIG. 4A
towards the fixed clamping element 120 such that in the closed
position the clamping surface 113 of the moveable clamping element
110 abuts onto the clamping surface 123 of the fixed clamping
element 120 at least along a clamping line, optionally wherein the
clamping surfaces 113, 123 abut on each other in a laminar manner.
While it may be sufficient that the clamping surfaces only abut on
each other along a clamping line, a high pressure may be present
along the clamping line and hairs may be cut or may break during
the plucking procedure due to this high pressure. Hence, a laminar
clamping area may tend to reduce the number of hairs that are cut
or that break.
[0063] FIG. 4B also shows the maximum length extensions L22 and L33
of the guiding surfaces of the winged sections as set forth in
claims 1 and 2. The skin contact surface 342 of the winged section
follows the shape of an imaginary enveloping cylinder 40.
[0064] One may define an effective hair catching area A, which is
the area from which hairs are clamped by a clamping unit,
neglecting the effect of guiding surfaces that may guide hairs from
an enlarged area into the gap. The effective hair catching area A
is then depending on the clamping length l of the clamping unit,
the closure velocity c with which the clamping elements of the
clamping unit are closed, the gap width d, and the velocity v with
which the clamping unit is moved relative to the skin, so that
A=d(l-1/2 vd/c). A typical closure speed c may lie in the range of
between about 0.7 m/s to about 1.3 m/s, in particular at about 1
m/s. Thus, the effective hair catching area in relation to the
closure time for a closure speed of 1000 mm.sup.2/s for a typical
clamping length of 4.0 mm as known from prior art devices, a gap
width of 0.9 mm and a movement velocity of 2000 mm/s is 2790 mm/s.
The overall hair epilation effectiveness will become increased if
the parameters of a clamping unit and the epilator are chosen such
that the effective hair catching area in relation to the closure
time is at least 3500 mm.sup.2/s or at least 4000 mm.sup.2/s or at
least 4500 mm.sup.2/s.
[0065] FIG. 5A is a schematic depiction of a clamping unit 200 of
an epilator in accordance with at least an aspect of the present
disclosure, which clamping unit 200 is shown in an open position.
The clamping unit 200 comprises a moveable clamping element 210 and
a fixed clamping element 220. Similarly to the clamping unit 100
shown in FIGS. 4A and 4B, the moveable clamping element has a
clamping section 211 and a winged section 212, where the clamping
section 211 has a clamping surface 213 and the winged section 212
has a guiding surface 214 that angles outwardly away from the
clamping surface 213 at an angle 215. Accordingly, the fixed
clamping element 220 has a clamping section 221 and a winged
section 222, where the clamping section 221 has a clamping surface
223 and the winged section 222 has a guiding surface 224 that
angles outwardly away from the clamping surface 223 at an angle
225. The clamping surfaces 213 and 223 are arranged essentially
opposite to each other and are separated in the open position by a
gap 230 that is sized to receive hairs. In the shown example
embodiment, the winged section 212 of the moveable clamping element
210 is hinged at the clamping section 211 with a hinge 219 and the
winged section 211 has a free end 216 that is in contact with a
stopper element 240. The hinge 219 may be realized by an elastic
material arranged between the clamping section 211 and the winged
section 212, which both may be made from a metal sheet material.
The winged section 212 is under a pre-stress F such that the angle
at which the guiding surface 214 would angle outwardly away from
the clamping surface 213 in an unconditioned situation would be
larger than angle 215 indicated in FIG. 5A, which angle 215 is
determined by the relative position of a stopper element 240
providing a constraint for the winged section 212 to move under the
present pre-stress F. As is indicated by arrow N, the moveable
clamping element 210 will be moved towards the fixed clamping
element 220 in order to achieve the closed position shown in FIG.
5B. When the movable clamping element 210 is moved along direction
N, the free end 216 of the winged section 212 of the moveable
clamping element 210 will stay in contact with the stopper element
240 due to the acting pre-stress F and will move along direction
P.
[0066] FIG. 5B schematically shows the closed position of the
clamping unit 200 shown in FIG. 5A. In the closed position, the
clamping surfaces 213, 223 of the moveable and the fixed clamping
elements 210, 220 abut on each other at least along a clamping
line. In the closed position, the guiding surface 214 of the winged
section 212 of the moveable clamping element 210 is angled
outwardly away from the clamping surface 213 at an angle 215A that
is larger than the angle 21 the respective surfaces have in the
open position shown in FIG. 5A.
[0067] It is noted that the provision of a winged section of a
moveable clamping element being under a pre-stress such that the
width of the guiding surface of the winged section increases when
the clamping unit is closed is considered as an independent aspect
of the present disclosure, while it shall not be excluded that this
feature may be combined with all other features described in the
present disclosure.
[0068] In some embodiments, a plurality of 40 clamping units as
shown in FIG. 4A or 5A may be arranged on a clamping cylinder as
shown in FIG. 3A. The clamping cylinder may have an effective
clamping width of 31.9 mm, while the gap width of each clamping
unit may be 0.6 mm and the total funnel width of each clamping unit
may be about 2.6 mm. Then, assuming that the gaps of the clamping
units are arranged on the clamping cylinder such that they do not
overlap in longitudinal cylinder axis direction, the total gap
width (i.e. the sum of all the 40 gap widths of each 0.6 mm) is 24
mm, which means that the clamping cylinder has a gap coverage of
only about 61%. On the other hand, as the added total funnel width
of all clamping units is 104 mm, this means that the clamping
cylinder is covered by the funnels at about 326%. In other words,
each hair growing on the skin may get clamped and plucked by more
than three clamping units per revolution of the clamping cylinder.
It is considered a general aspect of the present disclosure that
the gap coverage of an epilating cylinder is less than 100% while
the funnel coverage is above 100%. In particular, the gap coverage
may be in a range of between about 20% to about 95% (in particular
of between about 50% to about 80%) and additionally or
alternatively the funnel coverage may be in a range of about 105%
to about 500% (in particular of between about 150% to about 450%
and further optionally where the lower funnel coverage value may be
at least 200% or even at least 300%). It has been found that a
distance between clamping units in longitudinal cylinder axis
direction that is larger than the gap width (in particular wherein
the distance is at least 25% larger than the gap width or further
in particular wherein the distance is at least 30% larger than the
gap width) and optionally additionally with a circumferential
arrangement of the clamping units such that each clamping unit has
a different angular position on the circumference of the clamping
cylinder (e.g. in case of 40 clamping units, the angular distance
between the clamping units may be 9 degrees) supports the provision
of enough space to realize the large funnel widths for the clamping
units.
[0069] FIG. 6 is a cross sectional cut through an example
embodiment of a clamping cylinder 300, where the cross sectional
cut was taken in a plane perpendicular to the longitudinal cylinder
axis. A movable clamping element 310 can be seen that has a
clamping surface 313 that extends along a clamping length l (the
clamping length l being measured at the top level of the moveable
clamping element 310, which top level is defined by the top surface
310A of the moveable clamping element 310, which top surface 310A
is intended to contact the skin of a user during operation). It is
also noted that in the shown embodiment, the outer surface 310A of
the moveable clamping element follows the curvature of the
cylinder. Also, three cuts through fixed clamping element parts can
be seen, one of which is exemplary identified as fixed clamping
element 320 having a top surface 320A intended for contact with the
skin of a user during operation. The outer surfaces 310A, 320A lie
on an outer enveloping cylinder that has a diameter D1, which
diameter D1 may lie in a range of between about 10 mm to about 40
mm. It can further be seen in FIG. 6 that a regular pattern of
ridges 336 (which may extend parallel to the cylinder axis C as is
shown in FIG. 3A) is arranged on a lower level cylinder surface,
which lower level cylinder is coaxial with the enveloping cylinder
and has a diameter D2, where D2<D1. In some embodiments, D2 may
be around 80% of D1. In some embodiments, the clamping length l
extends over about 36 degrees of the angular range measured from
the centre point of the cross sectional cut or in other words, the
clamping length l may be about 10% of the perimeter of the outer
enveloping cylinder, i.e. l=0.12.pi.D1/2. Generally, the clamping
length l may be in a range of between about 8% to about 12% of the
perimeter of the enveloping cylinder, in particular it may lie in a
range of between about 8.5% to about 10.5%. While generally an
increase of the clamping length l may increase the efficiency of
the clamping cylinder, the clamping element also needs to have
contact with the skin over its clamping length as otherwise the
efficiency may not further increase due to non-clamped hairs. It
has been found that a clamping length of about one tenth of the
perimeter of the clamping cylinder defines a compromise between
efficiency increase due to length increase and reliable skin
contact over the full length extension.
[0070] FIG. 6 also shows the start and end points 340, 341 of the
circumferential discrete extension of the clamping unit which spans
a maximum angle of less than 90 degrees.
[0071] The dimensions and values disclosed herein are not to be
understood as being strictly limited to the exact numerical values
recited. Instead, unless otherwise specified, each such dimension
is intended to mean both the recited value and a functionally
equivalent range surrounding that value. For example, a dimension
disclosed as "40 mm" is intended to mean "about 40 mm".
[0072] Every document cited herein, including any cross referenced
or related patent or application, is hereby incorporated herein by
reference in its entirety unless expressly excluded or otherwise
limited. The citation of any document is not an admission that it
is prior art with respect to any invention disclosed or claimed
herein or that it alone, or in any combination with any other
reference or references, teaches, suggests or discloses any such
invention. Further, to the extent that any meaning or definition of
a term in this document conflicts with any meaning or definition of
the same term in a document incorporated by reference, the meaning
or definition assigned to that term in this document shall
govern.
[0073] While particular embodiments of the present invention have
been illustrated and described, it would be obvious to those
skilled in the art that various other changes and modifications can
be made without departing from the spirit and scope of the
invention. It is therefore intended to cover in the appended claims
all such changes and modifications that are within the scope of
this invention.
* * * * *