FIELD OF THE INVENTION
[0001] The present disclosure is concerned with a head of a personal care device comprising
a separate head portion that is positionally confined at a head housing by a first
locking element.
BACKGROUND OF THE INVENTION
[0002] It is known that personal care devices may comprise small parts or sharp parts. It
is generally advisable to arrange such personal care devices so that these parts do
not easily disassemble or detach from the personal care device even in case the device
is dropped in use to a stone floor as small parts may be swallowed by children or
a user or other person may step onto a sharp part with a bare foot, which is not unusual
if the personal care device is used in the bathroom in a regular morning personal
care procedure.
[0003] It is thus an object to provide a head for a personal care device and a personal
care device comprising such a head, where parts of the head are less prone to detach
from the head in an impact event.
SUMMARY OF THE INVENTION
[0004] In accordance with at least one aspect, a head for a personal care device is provided
that comprises a head housing having a top aperture and a bottom portion arranged
for attachment to a body of the personal care device, a separate head portion, preferably
a treatment assembly, extending through and beyond the top aperture, a first locking
element for positionally confining the separate head portion at the head housing,
the head housing comprising at least a first mechanical engagement element and the
first locking element comprising at least a second mechanical engagement element,
the first and the second mechanical engagement elements being mechanically engaged
for positionally locking the first locking element at the head housing, and the head
housing further comprising at least a third mechanical engagement element positioned
underneath the first mechanical engagement element with respect to a direction from
the top aperture towards the bottom portion, the third mechanical engagement element
being structured for engagement with the second mechanical engagement element.
[0005] In accordance with at least one aspect, a head for a personal care device is provided
that comprises a head housing having a top aperture and a bottom portion arranged
for attachment to a body of the personal care device, a separate head portion, preferably
a treatment assembly, extending through and beyond the top aperture, a first locking
element for positionally confining the treatment assembly at the head housing, a second
locking element being disposed underneath the first locking element with respect to
a direction from the top aperture towards the bottom portion, the head housing comprising
at least a first mechanical engagement element and the first locking element comprising
at least a second mechanical engagement element, the first and the second mechanical
engagement elements being mechanically engaged for positionally locking the first
locking element at the head housing, and the head housing further comprising at least
a third mechanical engagement element and the second locking element comprising at
least a fourth mechanical engagement element, the third and the fourth mechanical
engagement elements being mechanically engaged for positionally locking the second
locking element at the head housing.
[0006] In accordance with at least one aspect, a personal care device is provided that comprises
a head as disclosed herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present disclosure will be further elucidated by a detailed description of example
embodiments and with reference to figures. In the figures
- Fig. 1A
- is a depiction of an example personal care device comprising a head and a body;
- Fig. 1B
- is a depiction of the device of Fig. 1A with the head being detached from the body;
- Fig. 2A
- is a depiction of the head shown in Figs. 1A and 1B in isolation;
- Fig. 2B
- is a cross-sectional cut through the head of Fig. 2A;
- Fig. 2C
- is a cross-section cut through the head of Fig. 2A along a plane as indicated in Fig.
2B;
- Fig. 3
- is a depiction of an example first locking element;
- Fig. 4
- is a cross-sectional cut through a head as shown in Fig. 2B but after a force has
pushed a separate head portion inward;
- Fig. 5
- is a cross-sectional cut through a top portion of an example personal care device
comprising a first locking element and a second locking element; and
- Fig. 6
- is a magnification of a portion of a cross-sectional cut through an example personal
care device.
DETAILED DESCRIPTION OF THE INVENTION
[0008] In the context of the present description "personal care" shall mean the nurture
(or care) of the skin and of its adnexa (i.e. hairs and nails) and of the teeth and
the oral cavity (including the tongue, the gums etc.), where the aim is on the one
hand the prevention of illnesses and the maintenance and strengthening of health and
on the other hand the cosmetic treatment and improvement of the appearance of the
skin and its adnexa. It shall include the maintenance and strengthening of wellbeing.
This includes skin care, hair care, and oral care as well as nail care. This further
includes grooming activities such as beard care, shaving, and depilation. A "personal
care device" thus means any device for performing such nurturing or grooming activity,
e.g. (cosmetic) skin treatment devices such as skin massage devices or skin brushes;
wet razors; electric shavers or trimmers; electric epilators; and oral care devices
such as manual or electric toothbrushes, (electric) flossers, (electric) irrigators,
(electric) tongue cleaners, or (electric) gum massagers. This shall not exclude that
the proposed personal care device may have a more pronounced benefit in one or several
of these nurturing or device areas than in one or several other of these areas. In
the present description, an electric rotary shaver was chosen to present details of
the proposed personal care device. To the extent in which the details are not specific
for an electric rotary shaver, the proposed technology can be used in any other personal
care device.
[0009] In accordance with the present disclosure, a head for a personal care device comprises
a separate head portion that is positionally confined at a head housing by a first
locking element. The separate head portion may be a treatment assembly for providing
a personal care treatment, e.g. a cutter assembly comprising an outer cutter element
and an inner cutter element. In the following, the separate head portion is exemplified
by a rotary cutter assembly for a rotary shaver that provides facial skin care or
body skin care by means of shaving off hairs to improve the appearance of the skin.
The basic structure of the head shall be understood as comprising a hollow head housing
that defines a top aperture through which the separate head portion extends. The separate
head portion may extend beyond the top aperture. The head housing further comprises
a bottom portion that is arranged for in particular detachable attachment to a body
of the personal care device so that the head and the body together form the personal
care device when they are attached to each other. The bottom portion of the head housing
and a body housing of the body may comprise mechanical connection elements such as
coupling partners of a bayonet mount or partners of a snap connection to establish
the connection.
[0010] The head housing and the first locking element are mechanically engaged with each
other to secure the first locking element at the head housing under normal operation
conditions. To establish the mechanical engagement, the head housing and the first
locking element each have at least one mechanical engagement element that together
form at least a first engaged pair of mechanical engagement elements. The head housing
and the first locking element may each comprise one or several further mechanical
engagement elements and some of them may form further engaged pairs of mechanical
engagement elements. In accordance with some aspects, the head may comprise a second
locking element that has as well one or several mechanical engagement elements of
which at least one is mechanically engaged with a mechanical engagement element of
the head housing.
[0011] The mechanical engagement elements may be realized as projections and recesses, in
particular as snap-fit connection elements such a as a protruding edge and a corresponding
snap-in area, where at least one of the partners of the snap-fit connection is arranged
to elastically deform in an attachment process and optionally also in a detachment
process. This shall not exclude that the whole first locking element and/or the second
locking element can elastically deform instead of just the mechanical engagement element
or that both can elastically deform. In the examples described below, it is the whole
first locking element and the whole locking element that can elastically deform. In
the following, the head housing is said to comprise a first mechanical engagement
element and the first locking element to comprise a second mechanical engagement element
and the head housing further comprises a third mechanical engagement element. In examples
comprising a second locking element, the second mechanical engagement element comprises
a fourth mechanical engagement element. The terms "first", "second", "third" and "fourth"
are not to be understood as a numbering having any specific meaning but are used for
semantically differentiating the mechanical engagement elements. The head housing
and the first and second locking elements may each comprise one or several further
mechanical engagement elements. In the examples shown in the figures, the head housing
comprises four mechanical engagement elements and the first locking element comprises
two mechanical engagement elements (likewise, the second locking element also comprises
two mechanical engagement elements in the respective examples). But this shall not
be understood as limiting. Without being limited by theory, the first and third mechanical
engagement elements may be provided on an inner side of the head housing.
[0012] While it shall not be excluded that the head housing, the first locking element or
the second locking element are made at least partially from metal or any other suitable
material, the respective parts shown in the figures shall be understood as consisting
of a plastic material allowing the parts to be made by a plastic injection molding
process.
[0013] In some examples, the head housing and the first locking element are secured to each
other by at least a first engaged pair of mechanical engagement elements and optionally
by at least a second engaged pair of mechanical engagement elements. The head housing
comprises a first mechanical engagement element that is part of the first engaged
pair of mechanical engagement elements and the first locking element comprises a second
mechanical engagement element that is as well part of the first engaged pair of mechanical
engagement elements. The direction from the top aperture towards the bottom portion
(such as a direction along a center axis or longitudinal axis of the head) provides
the reference for terms like "above" or "underneath". E.g., if part A is above part
B then part A is closer to the top aperture than part B and vice versa for underneath.
[0014] In all examples, the head housing comprises a third mechanical engagement element
that is provided underneath the first mechanical engagement element. In accordance
with some examples, the third mechanical engagement element is arranged to be able
to become engaged with the second mechanical engagement element, e.g. the third mechanical
engagement element may essentially be a copy of the first mechanical engagement element.
Typically, the third mechanical engagement element is aligned in position with the
first mechanical engagement element with respect to the direction from the top aperture
to the bottom portion. In an impact event, when a force acts on the separate head
portion, which force is then transferred to the first locking element, the first and
the second mechanical engagement elements may become disengaged and the first locking
element may then be pushed downwards, i.e. towards the bottom portion of the head
housing. But the second mechanical engagement element may then become engaged with
the third mechanical engagement element. The distance between the first mechanical
engagement element and the third mechanical engagement element may be chosen so that
the separate head portion is then flush with the head housing portion defining the
top aperture. The force acting on the separate head portion then acts also or only
on the head housing and cannot further push the separate head portion downwards. The
first locking element would then not disengage from the head housing and would still
positionally confine the separate head portion with respect to the head housing. The
separate head portion or parts thereof will then not detach from the head, e.g. when
the head detaches from the body of the personal care device due to the impact or when
a user detaches the head from the body. The risk stemming from small parts and/or
sharp parts that detach from the head is thus effectively reduced. The position of
the third mechanical engagement element may be chosen so that in an attached state,
i.e. when the head is attached to a body of a personal care device, a lower contact
surface may essentially be in contact with a stopper surface of a body housing.
[0015] The first mechanical engagement element and/or the second mechanical engagement element
may comprise a chamfer that supports that the first and second mechanical engagement
elements can disengage from each other in an impact event with a lower risk of destruction,
e.g. plastic deformation of one of the mechanical engagement elements or even cutting
off of a piece from one of the mechanical engagement elements.
[0016] In accordance with some examples, the third mechanical engagement element is engaged
with a fourth mechanical engagement element of a second locking element. The first
locking element is thus supported in its locking function by the second locking element.
In the attached state, i.e. when the head is attached to the body of the personal
care device), the second locking element may abut a stopper surface of the body housing
or may at least be arranged close to a portion of the body housing so that the second
locking element cannot become detached from the head housing in an impact event but
would transfer the impact force to the body housing, which portion of the body may
provide the stopper surface. Even if the first locking element would become detached
from the head housing or if the first locking element would become destroyed in a
manner that it could not perform its locking function, the second locking element
would then probably still be in place to positionally confine the separate head portion
at the head housing.
[0017] Fig. 1A is a depiction of an example personal care device 1, here realized as a rotary
shaver. The personal care device 1 has a head 100 and a body 200. The head 100 comprises
a head housing 101 and a separate head portion 110 that is positionally confined at
the head housing as will be explained in detail further below. The separate head portion
110 is here realized as a treatment assembly, specifically as a cutter assembly of
a rotary shaver. The personal care device extends along a longitudinal axis L.
[0018] Fig. 1B is a depiction of the personal care device 1 shown in Fig. 1A but in a state
in which the head 100 is detached from the body 200. The head 100 may be attachable
to the body 200 by means of a bayonet mount, but this is just of many attachment possibilities
generally known by a skilled person and should not be understood as limiting. The
body comprises a drive shaft 210 for interaction with a drive shaft receiver element
so that in operation a motion of the drive shaft 210 can be transmitted to a movable
part of the separate head portion 110 (e.g. to a movable inner cutter element).
[0019] Fig. 2A is an isolated depiction of the head 100 shown in Figs. 1A and IB. As was
explained, the head 100 comprises a head housing 101 and a separate head portion 110
here realized as a treatment assembly, namely as a shaver assembly, specifically as
a rotary shaver assembly. The shaver assembly here comprises an outer static cutter
element 111 and a movable inner cutter element as can be better seen in Fig. 2B. The
separate head portion 110 extends through and beyond a top aperture 102. Further,
the head 100 comprises a bottom portion 103 that is arranged for coupling with a body
of a personal care device as shown in Figs. 1A and 1B. The head 100 has a longitudinal
axis L that centrally extends through the top aperture 102 and the bottom portion
103. In the following it will be referred to a direction from the top aperture 102
towards the bottom portion 103. It shall be understood that this direction is coinciding
with the longitudinal axis and thereby defines a reference for terms like "above"
or "underneath", where above shall mean that something is closer to the top aperture
102 than something else and underneath that something is closer to the bottom portion
than something else. E.g. the phrase "part A is arranged underneath part B with respect
to the direction from the top aperture towards the bottom portion" means that part
A is located closer to the bottom portion than part B.
[0020] Fig. 2B is a cross-sectional cut through the head 100 shown in Fig. 2A. The head
100 comprises a head housing 101 having a top aperture 102, a bottom portion 103,
a bottom aperture 104 and an inner side 130, a separate head portion 110 and a first
locking element 120. The separate head portion 110 is realized as a treatment assembly,
namely as a shaver assembly for providing a hair cutting treatment. The cutter assembly
comprises an outer cutter element 111 intended for getting into skin contact, the
outer cutter element 111 comprising openings for hairs to extend through to get cut
by a movable cutter element 112, namely a movably arranged set of cutting knives that
in operation will glide along an inner surface of the outer cutter element 111 in
the area of the mentioned slits. The cutter assembly here also comprises a drive shaft
receiver 113 for receiving a drive shaft of the body of the personal care device as
was discussed in connection with Fig. 1B.
[0021] The separate head portion 110 extends through and beyond the top aperture 102 and
the separate head portion 110 is positionally confined at the head 100 by a first
locking element 120. The head housing 101 has a first mechanical engagement element
131 formed on the inner side 130 of the head housing 101, which first mechanical engagement
element 131 is engaged with a second mechanical engagement element 121 of the first
locking element 120. The first mechanical engagement element 131 and the second mechanical
engagement element 121 together form a first engaged pair of mechanical engagement
elements. In the shown example, the head 100 comprises a second engaged pair of mechanical
engagement elements 122, 132 provided by the first locking element 120 and the head
housing 101, where a mechanical engagement element 122 is formed at the first locking
element and another mechanical engagement element 132 is formed at the head housing
101. Without limitation, the first mechanical engagement element 131 is here realized
as a depression in the inner side 130 of the head housing 101 and the second mechanical
engagement element 121 is realized as a projection of the first locking element 120.
In addition, the head housing 101 comprises a third mechanical engagement element
133 that is located underneath the first mechanical engagement element 131. The third
mechanical engagement element 133 is essentially a copy of the first mechanical engagement
element and thus arranged to engage with the second mechanical engagement element
121. The head housing 101 here also comprises one or several projections 139 disposed
on the inner side 130 of the head housing 101 in the bottom portion 103. These projections
139 are suitable for engaging with a bayonet receptor in the body of the personal
care device as discussed in connection with Fig. 1B.
[0022] Fig. 2C shows a cross-sectional cut through the head 100 taken along plane A-A as
indicated in Fig. 2B, where the view direction is from the bottom up. The head housing
101 comprises the first mechanical engagement element 131 and another mechanical engagement
element 132 that are here realized as depressions or recesses in the inner side 130
of the head housing 101. The first locking element 120 is here realized as a ring-like
element that has here two projections that realize the second mechanical engagement
element 121 and a further mechanical engagement element 122. The first mechanical
engagement element 131 and the second mechanical engagement element 121 together form
a first engaged pair of mechanical engagement elements 1231 and the further mechanical
engagement elements form a second engaged pair of mechanical engagement elements 1232.
In the process of assembling the head 100, the ring-like first locking element will
deform, e.g. into a more elliptic shape until the projections 121 and 122 snap into
the recesses 131 and 132 of the head housing 101. As was already discussed, the first
locking element 120 may have any suitable shape and the ring-like shape shown here
is just one example that is suited for positionally confining a circular cutter assembly
at the head housing 101.
[0023] Fig. 3 is a perspective depiction of the first locking element 120 of Figs. 2B and
2C shown in isolation. The ring-like first locking element 120 has two projections
121 and 122 and a top contact surface 128 and a bottom contact surface 129.
[0024] Fig. 4 is a cross-sectionally cut through the head 100 shown in Figs. 2A to 2C after
an external force F has acted on the separate head portion 110 that is realized as
a rotary cutter assembly. Such an external force F may act on the separate head portion
110, specifically at the outer cutter element 111 when the head 100 hits the ground,
e.g. after a user has dropped the personal care device. When the head 100 (specifically
when attached to the personal care device) hits the ground, a force may act on the
separate head portion 110 that is transferred to the first locking element 120 and
that may cause that the second locking element 121 becomes disengaged from the first
mechanical engagement elements 131. In the shown example, a further pair of engaged
mechanical engagement elements 122, 132 became disengaged. The separate head portion
110 that has originally extended beyond the top aperture 102 as is indicated with
dotted lines was be pushed into the head housing 101 when it hits the ground - it
is here assumed that it hits the ground in a straight top-down manner where the force
F is evenly distributed over the outer area of the separate head portion 110, namely
here the outer cutter element 111. Once the separate head portion 110 is completely
pushed into the housing 101, the force F will act on the head housing 101 and the
separate head portion 110 can then not be further pushed inside the head housing 101.
The head housing 101 may be structured to absorb the energy of the impact on the ground
by elastic deformation and the head housing 101 will also transfer impact energy onto
the body housing of the personal care device so that the device may not fracture when
it is dropped. The distance by which the separate head portion 110 is pushed inwards
is indicated by reference numeral d. The third mechanical engagement element 133,
which is structured to allow engagement with the second mechanical engagement element
121, is located underneath the first mechanical engagement element 131 at a distance
d, i.e. once the pushing inwards of the separate head portion 110 is stopped in the
position as shown in Fig. 4 where the outer surface of the separate head portion 110
is flush with the head housing portion defining the top aperture 102, then the first
locking element 120 is at a position so that the third mechanical engagement element
133 and the second mechanical engagement element 121 can engage as is shown. In this
example, also the further mechanical engagement element 122 of the first locking element
became engaged with a further mechanical engagement element 134 of the head housing
101. The first locking element 120 will then still positionally confine the separate
head portion 110 at the head housing 101 and even if the head 100 would disengage
from the body of the personal care device when it hits the ground, the separate head
portion 110 would not detach from the head 100. The latter may be specifically problematic
if - as in the shown example - the separate head portion is a cutter assembly that
comprises a very sharp inner cutter element 112. While the described impact event
is a highly dynamic process, the elastic deformations of the various parts of the
head 100 are here not discussed. As can be better understood from Fig. 5, the position
of the third mechanical engagement element 133 may be chosen so that a contact surface
129 of the first locking element 120 may come into contact with a stopper surface
of the body housing of the body in the attached state of the head 100.
[0025] Further, the second mechanical engagement element 121 may comprise a chamfer 1221
that supports a non-destructive disengagement of the second mechanical engagement
element 121 from the first mechanical engagement element 131. The first and the third
mechanical engagement elements and eventually further mechanical engagement elements
provided at the head housing 101 may each comprise an outer chamfer 1311, 1321, 1331,
1341 that supports a non-destructive assembling of the first locking element 120.
A user may be able to re-insert the first locking element 120 into its upper original
position by applying an upwards directed force onto the first locking element 120.
[0026] As can be better understood with reference to Fig. 5, the head housing and the body
housing may be designed so that a lower contact surface 129 of the first locking element
120 contacts a stopper surface of the body housing so that a disengagement of the
first locking element 120 from the lower engagement position shown in Fig. 4 is effectively
prevented.
[0027] When the head 100 hits the ground, the force F acting on the separate head portion
110 and thus on the first locking element 120 may cause a destruction of at least
one of the first mechanical engagement element 131 or the second mechanical engagement
element 121. In the shown example, the projection forming the second mechanical engagement
element 121 may simply be shorn off. In order to reduce the risk of such a destruction,
the second mechanical engagement element 121 may comprise a chamfer 1211 as was already
discussed and/or the first mechanical engagement element 131 may comprise an inner
chamfer so that in the impact event the engaged first and second mechanical engagement
elements 131 and 121 can disengage without a relevant destruction or plastic deformation.
[0028] Fig. 5 is a cross-sectional cut through an example head 100A, where a first locking
element 120A and a second locking element 140A serve to positionally confine a separate
head portion 110A at a head housing 101A. In the shown example, the head housing comprises
a first mechanical engagement element 131A, a third mechanical engagement element133A
and two further mechanical engagement elements 132A and 134A; the first locking element
120A comprises a second mechanical engagement element 121A and a further mechanical
engagement element 122A; and the second locking element 140A comprises a fourth mechanical
engagement element 141A and a further mechanical engagement element 142A. The first
mechanical engagement element 131A and the second mechanical engagement element 121A
are engaged as are the further mechanical engagement elements 132A and 122A; the third
mechanical engagement element 133A and the fourth mechanical engagement element 141A
are engaged as are the further mechanical engagement elements 134A and 142A. The first
locking element 120A has a lower contact surface 129A and the second locking element
140A has an upper contact surface 148A, which are facing each other, and which may
get into contact in an impact event. The second locking element 140A has a lower contact
surface 149A that here abuts a stopper surface 202A of the body housing 201A. In an
impact event, the separate head portion 110A will be pushed inwards and will act on
the first locking element, which may get into contact with the second locking element,
which will transfer the acting forces onto the body housing 201A. Even if the first
locking element 120A gets destroyed in an impact event, the second locking element
140A may probably survive the impact event and will then still positionally confine
the separate head portion 110A at the head housing 101A. As is also shown in Fig.
5, the body comprises a drive unit comprising a drive shaft 211A to which drive adapter
210A is attached, which drive adapter is engaged with a drive shaft receiver 113A
so that motion can be transferred from the drive unit to a movable part 112A of the
separate head portion 120A.
[0029] Fig. 6 is a cross-sectional cut through a portion of an example head 100B attached
to a body housing 201B of a body of a personal care device - Fig. 6 is rather similar
to what is shown in and discussed with reference to Fig. 5. The head 100B comprises
a separate head portion 110B realized as a cutter assembly. The separate head portion
110B is positionally confined at a head housing 101B by a first locking element 120B.
The head housing 101B comprises a first mechanical engagement element 131B that is
engaged with a second mechanical engagement element 121B of the first locking element
120B. The second mechanical engagement element 121B comprises a chamfer 1211B arranged
on the lower side of the second mechanical engagement element 121B so that it can
glide along a lower edge 135B of the first mechanical engagement element 131B when
a force acts on the first locking element 120B to push it downwards. The head housing
101B comprises a third mechanical engagement element 133B that is engaged with a fourth
mechanical engagement element 141B of a second locking element 140B. The fourth mechanical
engagement element 141B comprises a chamfer 1411B arranged on the lower side of the
second mechanical engagement element 141B so that it can glide along a lower edge
of the third mechanical engagement element 133B when a force acts on the first locking
element 120B to push it downwards. In difference to the example shown in Fig. 5, a
lower contact surface 149B of the second locking element 140B is arranged at a distance
c to a stopper surface 202B of the body housing 201B. The gap, i.e. distance c, may
be chosen to be smaller than a thickness of second locking element 140B so that the
latter can elastically deform in an impact event but will not disengage from the head
housing 101A as it is stopped by the stopper surface 202B prior to any disengagement.
[0030] 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."
1. A head for a personal care device, comprising
a head housing having a top aperture and a bottom portion arranged for attachment
to a body of the personal care device;
a separate head portion, preferably a treatment assembly, extending through and beyond
the top aperture;
a first locking element for positionally confining the separate head portion at the
head housing;
the head housing comprising at least a first mechanical engagement element and the
first locking element comprising at least a second mechanical engagement element,
the first and the second mechanical engagement elements being mechanically engaged
for positionally locking the first locking element at the head housing; and
the head housing comprising at least a third mechanical engagement element positioned
underneath the first mechanical engagement element with respect to a direction from
the top aperture towards the bottom portion, the third mechanical engagement element
being structured for engagement with the second mechanical engagement element.
2. The head in accordance with claim 1, wherein the position of the third mechanical
engagement element is chosen such that the separate head portion can assume a position
in which a portion of the separate head portion that extended beyond the top aperture
is flush with the top aperture when the second mechanical engagement element and the
third mechanical engagement element are engaged.
3. A head of a personal care device, comprising
a head housing having a top aperture and a bottom portion arranged for attachment
to a body of the personal care device;
a separate head portion, preferably a treatment assembly, extending through and beyond
the top aperture;
a first locking element for positionally confining the treatment assembly at the head
housing;
a second locking element being disposed underneath the first locking element with
respect to a direction from the top aperture towards the bottom portion;
the head housing comprising at least a first mechanical engagement element and the
first locking element comprising at least a second mechanical engagement element,
the first and the second mechanical engagement elements being mechanically engaged
for positionally locking the first locking element at the head housing; and
the head housing comprising at least a third mechanical engagement element and the
second locking element comprising at least a fourth mechanical engagement element,
the third and the fourth mechanical engagement elements being mechanically engaged
for positionally locking the second locking element at the head housing.
4. The head in accordance with claim 3, wherein the first locking element and the second
locking element are separated by a gap, preferably wherein a width of the gap in the
direction from the top aperture towards the bottom portion is smaller than a thickness
of the first locking element in the direction between the top aperture and the bottom
portion.
5. The head in accordance with any one of claims 1 to 4, wherein the first mechanical
engagement element and the second mechanical engagement element form a first engaged
pair of mechanical engagement elements and where at least a second engaged pair of
mechanical engagement elements is provided by the first locking element and the head
housing.
6. The head in accordance with any one of claims 1 to 5, wherein the first locking element
or a portion of the first locking element comprising the second mechanical engagement
element is elastically deformable so that in an assembly process the first mechanical
engagement element and the second mechanical engagement element can become engaged
by a snapping action.
7. The head in accordance with any one of claims 1 to 6, wherein a chamfer is provided
at least at one of the first mechanical engagement element or the second mechanical
engagement element to support a non-destructive disengagement of the first mechanical
engagement element and the second mechanical engagement element.
8. The head in accordance with any one of claims 1 to 7, wherein the first mechanical
engagement element is realized as a recess and the second mechanical engagement element
is realized as a projection, preferably a chamfered projection.
9. The head in accordance with any one of claims 1 to 8, wherein the separate head portion
is a cutter assembly comprising an outer cutter element and a movable inner cutter
element, preferably wherein the cutter assembly is a rotary cutter assembly.
10. The head in accordance with any one of claims 1 to 9, wherein the first locking element
is a ring-like locking element.
11. A personal care device comprising a head in accordance any one of claims 1, 2 and
5 to 10 referring back to claims 1 and 2 or with any one of claims 3, 4 and 5 to 10
referring back to claims 3 and 4, further comprising a body of the personal care device,
the head and the body being detachably attached to each other.
12. The personal care device in accordance with the first alternative of the claim 11,
wherein the body has a stopper surface positioned underneath the first locking element
with respect to a direction from the top aperture towards the bottom portion, which
stopper surface essentially abuts the first locking element when the second mechanical
engagement element and the third mechanical engagement element are engaged.
13. The personal care device in accordance with the second alternative of claim 11, wherein
the body has a stopper surface positioned underneath the second locking element with
respect to a direction from the top aperture towards the bottom portion, which stopper
surface essentially abuts the second locking element.
14. The personal care device in accordance with the second alternative of claim 11, wherein
the body has a stopper surface, and the second locking element and the stopper surface
are separated by a gap, preferably wherein a width of the gap in the direction from
the top aperture towards the bottom portion is smaller than a thickness of the second
locking element in the direction from the top aperture towards the bottom portion.