FIELD OF THE INVENTION
[0001] The present invention is concerned with a hair removal device, e.g. a dry shaver,
a wet shaver or an epilator, comprising a handle, which encases e.g. a drive unit
and an energy source, and a head, which is pivotably supported on the handle and comprises
at least one hair removal unit coupled to the drive unit by means of a transmission
converting a rotary motion of the drive unit into a movement of a driven part of the
at least one hair removal unit.
BACKGROUND OF THE INVENTION
[0002] EP 2 404 716 B1 discloses an electrically powered shaver having a handle and a head with cutter elements
which extend parallel to a pivot axis and which can swivel about the pivot axis, thereby
permitting the cutters to follow the contours of the user's skin.
[0003] Pivoting of the head with respect to the handle is typically limited by abutment
of a stop face of a stop element with a counter-stop element. This limitation may
be required for protecting other component parts of the device during usage or if
the device is subject to external impact forces, e.g. when dropping the device. However,
abutment of the stop face with the counter-stop element may generate an undesired
tactile and/or audible feedback to a user in the form of a clacking noise and the
impression of a hard end stop.
[0004] It is an object of the present invention to provide an improved hair removal device
enhancing the sensation during use of the device. More particularly it is a further
object of the present invention to improve the above mentioned hair removal device
which comprises a hair removal head which is moveable relative to the handle in that
the head movement noise is suppressed or avoided or reduced.
SUMMARY OF THE INVENTION
[0005] In accordance with one aspect of the present disclosure, a hair removal device comprises
a handle, which encases at least a drive unit and an energy source, and a head, which
is pivotably supported on the handle and comprises at least one hair removal unit
coupled to the drive unit by means of a transmission converting an, e.g. rotary or
linear, motion of the drive unit into a movement of a driven part of the at least
one hair removal unit. Pivoting of the head with respect to the handle is limited
by abutment of at least one stop face of at least one stop element with at least one
counter-stop element. The at least one stop element is made by multi-component injection
moulding from a first plastic material and at least one second plastic material which
is softer than the first plastic material, wherein the at least one stop face is made
from the second plastic material.
[0006] Multi-component injection moulding is a highly efficient method for producing component
parts of different materials having material characteristics tailored to the respective
requirements. The combination of a harder or more rigid plastic material withstanding
e.g. mechanical loads with a softer plastic material permits damping of the abutment
limiting the pivoting of the head with respect to the handle. This increases user's
comfort and enhances the sensation during use of the device. In addition, the softer
plastic material may cushion e.g. mechanical loads if the device is subject to external
impact forces, e.g. when dropping the device. Providing such a multi-purpose component
part contributes in reducing cost and effort for producing and assembling the device
due to a reduced number of component parts compared with separate component parts
each fulfilling only one function.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007]
- Figure 1
- shows in a schematic perspective view a device according to an embodiment of the invention,
- Figure 2
- shows in a schematic side view components of the device of Figure 1,
- Figure 3
- shows in a schematic side view details of the device of Figure 1, and
- Figure 4
- shows in a schematic side view details of the device of Figure 1.
DETAILED DESCRIPTION OF THE INVENTION
[0008] Before describing advantageous embodiments of the invention related to the Figures
1 to 4, different aspects of the invention are described more in detail. These aspects
disclose further features, advantages and possibilities of use of the present invention
that might be combined in any useful combination. All features described and/or shown
in the drawings are subject matter of the invention, irrespective of the grouping
of the features in the claims and/or their back references.
[0009] The at least one stop element is made by multi-component injection moulding from
a first plastic material and at least one second plastic material which is softer
than the first plastic material. With respect to the present disclosure, the stop
element may be made by two-component injection moulding, i.e. comprising only the
first plastic material and a second plastic material. However, it may be desirable
to use more than two different plastic materials, especially if the stop element has
additional functions. For example, the softer second plastic material may be a thermoplastic
elastomer (TPE) or a (liquid) silicone rubber (LSR). The first plastic material is
typically a thermoplastic material which is rigid at ambient temperature, for example
polypropylene (PP) or polybutylene terephthalate (PBT).
[0010] The hair removal device may comprise an outer housing and an inner housing hermetically
encapsulating component parts which should be sealed off against humidity, for example
the drive unit and/or the energy source. The at least one stop element may be a shell
or part of a shell assembly sealing at least a portion of the hair removal device
off against the environment. In other words, the stop element may be a portion of
the outer housing or the inner housing. Preferably, the at least one stop element
comprises at least one sealing portion, for example a sealing lip or the like, made
from the second plastic material. According to an independent aspect of the present
disclosure, a component part of the hair removal device is made by two-component injection
moulding or multi-component injection moulding, wherein the softer material fulfills
a sealing function and in addition a function as a stop element.
[0011] As an alternative or in addition to the sealing function, wherein the at least one
stop element may comprise at least one soft rib made from the second plastic material,
wherein the soft rib exerts a biasing force on a component part abutting the soft
rib. The component part abutting the soft rib may be an axle, such that the soft rib
removes clearances between the axle and further parts hinged to the axle.
[0012] The at least one stop element may comprise separate regions consisting of the softer
second plastic material. As an alternative, regions consisting of the softer second
plastic material may be connected with each other, such that they form a common piece
of the second plastic material. Preferably, the at least one stop face and the at
least one sealing portion are connected with each other by a web made from the second
plastic material.
[0013] As mentioned above, the head of the hair removal device is pivotably supported on
the handle of the device. If the device is a shaver comprising a cutter element performing
substantially the longitudinal movement in use, the pivoting of the head with respect
to the handle may be a swiveling movement about the swiveling axis which is e.g. substantially
parallel to the direction of the longitudinal movement of the cutter element. As an
alternative or in addition, the pivoting of the head with respect to the handle may
be a tilting movement about a tilting axis which is e.g. substantially perpendicular
to the direction of the longitudinal movement of the cutter element. Further, the
head or the cutter element may be movable in a direction parallel to the main extension
of the handle, e.g. a plunging movement with respect to the handle.
[0014] According to an embodiment the head may be pivotably supported on the handle by means
of at least two levers which are each pivotably hinged to a support of the handle
and to the head, respectively. The levers may form a so-called 4-bar-mechanism permitting
a tilting movement of the head with respect to the handle. For example, at least one
of the levers is a metal component which may have a substantially U-shaped cross-section.
A part of the support of the handle may be the stop element having at least one stop
face made from the second plastic material for each lever. Further, each lever may
comprise a portion forming the at least one counter-stop element. According to a further
aspect, the support of the handle is a lid hermetically sealing an inner housing of
the handle, which inner housing encases the drive unit and the energy source.
[0015] In addition or as an alternative, the head may be supported on the handle pivotably
about a swivel axis. The head may comprise a frame supported on at least one, e.g.
two, swivel bearings aligned with the swivel axis. Abutment of the frame with a component
part which is constrained to the handle with respect to rotation about the swivel
axis may limit pivoting of the head relative to the handle about the swivel axis.
For example, the component part which is constrained to the handle with respect to
rotation about the swivel axis is an, e.g. plate-shaped, head part, wherein at least
one stop face made from the second plastic material is provided on the plate. The
head part or plate may have an opening receiving a drive shaft of the transmission.
Still further, the at least two levers may be pivotably hinged to the head part or
a further base plate which is constrained to the head part. The further base plate
may comprise two arms, wherein each arm comprises one of the swivel bearings.
[0016] The hair removal device may be a dry shaver, a wet shaver or an epilator. For example,
the hair removal device comprises at least one hair removal unit having a foil-type
upper cutter and a lower cutter with several blades. The transmission may be coupled
to the lower cutter for driving the lower cutter in a translational movement relative
to the upper cutter. In addition or as an alternative, the at least one hair removal
unit may comprise two or more combs moving relative to each other for cutting or removing
hairs.
[0017] Turning now to the exemplary embodiment depicted in the Figures, a hair removal device
1 is depicted in Figure 1 which comprises a handle 2 and a head 3 having several hair
removal units 4, 5. The two hair removal units 4 each comprise a foil-type upper cutter
and a lower cutter (not shown) with several blades which in use move axially with
respect to the foil-type upper cutter for shearing off hairs. The hair removal unit
5 comprises two combs moving relative to each other for cutting hairs.
[0018] In the depicted exemplary embodiment, the handle 2 has an elongate shape defining
a main axis of the hair removal device 1. The handle 2 may house component parts like
a drive unit 6, an energy source, e.g. a rechargeable battery, a control unit or the
like. This is schematically indicated in Figure 2 in dashed lines.
[0019] The head 3 is supported on the handle 2 such that the head 3 may perform a relative
movement with respect to the handle 2 permitting the hair removal units to follow
the contour of the user's skin. This is depicted in Figure 2 in more detail in which
component parts of the head 3 and of the handle 2 are omitted. The handle 2 comprises
a support 7 which may be a lid sealing off an interior space which houses for example
the drive unit 6 and the energy source. Four levers are pivotably hinged to the support
7, wherein two levers may be connected with each other to form an, e.g. U-shaped,
lever unit 8a, 8b. The levers are further pivotably hinged to a base plate 9 which
may be tilted, i.e. pivoted to the left and to the right in Figure 2, relative to
the support 7 by means of the levers. For example, the lever units may be sheet-metal
parts.
[0020] The base plate 9 comprises two arms 10 each having a swivel bearing 11, which bearings
11 are located on a swivel axis I, for example substantially perpendicular to the
main axis of the handle 2. The hair removal units 4, 5 are mounted in a frame 12 which
is pivotably supported on the arms 10 by the swivel bearings 11. In combination with
the lever units 8a, 8b, the swivel bearings 11 result in a gimbal-like mounting of
the frame 12 with respect to the support 7 permitting a swivel movement about the
swivel axis I and a tilting movement about an axis substantially perpendicular to
the swivel axis I.
[0021] The frame 12 may be received in or may be part of a casing of the head 3 as indicated
in Figure 1. Further, the hair removal units 4, 5 may be movable with respect to the
frame 12 and/or the casing of the head 3 in a plunging direction substantially parallel
to the main extension of the handle 2.
[0022] The pivoting movement of the levers may be limited by abutment of the levers with
the support 7 and/or the base plate 9. In the example depicted in Figure 3 each lever
comprises a nose 13 in the vicinity of the end facing away from the hair removal units
4, 5. As indicated in Figure 3, the nose 13 of the left lever unit 8a contacts the
support 7, thereby limiting tilting of the base plate 9 to the right. In a similar
manner the nose 13 of the right lever unit 8b would contact the support 7 if the base
plate would be tilted to the left. Thus, the support 7 defines a stop element and
the nose 13 defines a counter-stop element which together limit pivoting of the head
3 with respect to the handle 2.
[0023] The support 7 is a component part of the hair removal device 1 which has to bear
mechanical loads, for example due to the support of the head 3. Thus, the support
7 mainly consists of a rigid material. In the embodiment depicted in Figure 3, the
support 7 is made by two-component injection moulding using a first rigid plastic
material and a second softer plastic material. At least the area of the support 7
contacting the respective nose 13 of the lever for limiting the pivoting of the head
3 with respect to the handle 2, i.e. the stop face 14 of the support 7, consists of
the second softer plastic material, e.g. a thermoplastic elastomer. In other words,
although the support 7 is one component part, it consists of at least two different
materials, namely the rigid first plastic material and the softer second plastic material
forming the stop face 14 for abutment with the nose 13. This results in a soft stop
between the nose 13 and the support 7, thereby preventing undesired noise emission
or the sensation of a hard stop.
[0024] In addition or as an alternative, the stop face made from the second softer plastic
material may be provided on the levers and/or on the frame 12.
[0025] In a similar manner Figure 4 depicts an interface between the frame 12 and the base
plate 9, which interface comprises a soft stop. In more detail, the frame 12 is provided
with an edge or protrusion contacting the base plate 9 or a separate plate 15 attached
to the base plate 9 if that baseplate 9 is swiveled about swivel axis I as shown in
Figure 4. This abutment of the plate 15 which defines a stop element and the frame
12 which defines a counter-stop element limits pivoting of the head 3 with respect
to the handle 2 about swivel axis I. The plate 15 is made by two-component injection
moulding using a first rigid plastic material and a second softer plastic material.
At least the area of the plate 15 contacting the respective portion of the frame 12
for limiting the pivoting of the head 3 with respect to the handle 2, i.e. the stop
face 16 of the plate 15, consists of the second softer plastic material, e.g. a thermoplastic
elastomer. Again, this results in a soft stop limiting the pivoting of the head 3
with respect to the handle 2.
[0026] While the plate 15 is shown in Figure 4 as a separate component part constrained
to the base plate 9, the stop face 16 may be provided directly on the base plate 9.
As a further alternative or in addition to the above embodiments, a stop face consisting
of the second softer plastic material may be provided on the frame 12, for example
on the edge or protrusion contacting the baseplate nine or of the plate 15 for limiting
the pivoting of the head 3 with respect to the handle 2.
[0027] The component parts made by two-component injection moulding using a first rigid
plastic material and a second softer plastic material, i.e. the support 7 and/or the
plate 15, may have additional functions and/or additional areas consisting of the
second softer plastic material.
[0028] For example, the support 7 may be a lid hermetically closing an inner housing encasing
for example the drive unit 6 and/or the energy source. For this purpose the support
may be provided with a sealing lip 18 consisting of the second softer plastic material
for sealing of the lid (support 7) with respect to other inner housing components.
In an alternative embodiment not depicted in the Figures, the sealing lip 18 may be
a separate portion of the second softer plastic material not directly connected with
the stop face 16. As an alternative, the sealing lip may be connected with the stop
face 16 by a web of the second softer plastic material, e.g. channels 17 used for
distributing the second softer plastic material during injection molding.
[0029] As a further example the base plate 9 and/or the plate 15 may be a lid hermetically
closing the head 3 with respect to the environment. For this purpose the baseplate
9 and/or the plate 15 maybe provided with a sealing lip (not shown) consisting of
the second softer plastic material for sealing of the lid with respect to other portions
of the head 3. Again, the stop face 14 may be a separate portion of the second softer
plastic material or may be connected with the sealing lip by a web of the second softer
plastic material.
[0030] As a still further example, the second softer plastic material may have a portion
formed as a soft rib 19 provided on the base plate 9 and/or the plate 15. The soft
rib 19 may be arranged such that it acts on a pivot axle 20 of one of the lever units
8a, 8b connecting the baseplate 9 and/or the plate 15 with the support 7. In more
detail, the soft rib 19 may be arranged such that it is slightly compressed by abutment
with the pivot axle 20, thereby eliminating clearances between the axle 20, the lever
units 8a, 8b and the base plate 9 and/or the plate 15. Again, the stop face 14 may
be a separate portion of the second softer plastic material or may be connected with
the soft rib 19 by a web of the second softer plastic material.
[0031] Thus, the electric dry shaver comprises a moveable shaver head which swiveling range
is limited by stops elements having counter-stop elements made from a softer material
than the stop element and thus softening the abutment when the shaver head reaches
its extreme end positions. Almost no noise is therefore created by such shaver head
movements even if those reach the end positions. Advantageously the counter-stop elements
made form soft material, as e.g. TPE are made in multi-component injection molding
process. The part equipped with the soft counter stop element is provided with second
functional soft component part either on the same side as the counter stop element
or on the opposite side of the part. This second functional soft component part is
provided to serve for a different purpose than a stop or counter-stop element, i.e.
for providing a sealing lib or pretension protrusion rib. Therefore, the soft material
counter-stop is not only cost efficiently provided by the multi component injection
molding process but also the material serves for a double function in the same part.
[0032] 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."
Reference numerals:
[0033]
- 1
- hair removal device
- 2
- handle
- 3
- head
- 4
- hair removal unit
- 5
- hair removal unit
- 6
- drive unit
- 7
- support
- 8a, b
- lever unit
- 9
- base plate
- 10
- arm
- 11
- swivel bearing
- 12
- frame
- 13
- nose
- 14
- stop face
- 15
- plate
- 16
- stop face
- 17
- channel
- 18
- sealing lip
- 19
- soft rib
- 20
- pivot axle
- I
- swivel axis
1. A hair removal device comprising a handle (2), which encases a drive unit and an energy
source, and a head (3), which is pivotably supported on the handle (2) and comprises
at least one hair removal unit (4, 5) coupled to the drive unit by means of a transmission
converting a motion of the drive unit into a movement of a driven part of the at least
one hair removal unit (4, 5), wherein pivoting of the head (3) with respect to the
handle (2) is limited by abutment of at least one stop face (14, 16) of at least one
stop element (7, 15) with at least one counter-stop element (8a, 8b, 12), wherein
the at least one stop element (7, 15) is made by multi-component injection moulding
from a first plastic material and a second plastic material which is softer than the
first plastic material, and wherein the at least one stop face (14, 16) is made from
the second plastic material.
2. The hair removal device according to claim 1, wherein the at least one stop element
(7, 15) is made by two-component injection moulding.
3. The hair removal device according to claim 1 or 2, wherein the first plastic material
is polypropylene or polybutylene terephthalate and/or the second plastic material
is a thermoplastic elastomer or a liquid silicone rubber.
4. The hair removal device according to any of the preceding claims, wherein the at least
one stop element (7, 15) is a shell or part of a shell assembly sealing at least a
portion of the hair removal device (1) off against the environment, and wherein the
at least one stop element (7, 15) comprises at least one sealing portion (18) made
from the second plastic material.
5. The hair removal device according to any of the preceding claims, wherein the at least
one stop element (7, 15) comprises at least one soft rib (19) made from the second
plastic material, wherein the soft rib (19) exerts a biasing force on a component
part (20) abutting the soft rib (19).
6. The hair removal device according to claim 4 or 5, wherein the at least one stop face
(14, 16) and the at least one sealing portion (18) and/or soft rib (19) are connected
with each other by a web (17) made from the second plastic material.
7. The hair removal device according to any of the preceding claims, wherein the head
(3) is pivotably supported on the handle (2) by means of at least two levers (8a,
8b) which are each pivotably hinged to a support (7, 12) of the handle (2) and to
the head (3), respectively.
8. The hair removal device according to claim 7, wherein at least a part of the support
(7) of the handle (2) is the stop element (7) having at least one stop face (14) made
from the second plastic material for each lever (8a, 8b), wherein each lever (8a,
8b) comprises a portion forming the at least one counter-stop element.
9. The hair removal device according to claim 7 or 8, wherein the support (7) of the
handle (2) is a lid hermetically sealing an inner housing of the handle (2), which
inner housing encases the drive unit (6) and the energy source.
10. The hair removal device according to any of claims 7 to 9, wherein at least one of
the levers (8a, 8b) is a metal component and/or has a substantially U-shaped cross-section.
11. The hair removal device according to any of the preceding claims, wherein the head
(3) is supported on the handle (2) pivotably about a swivel axis (I), wherein the
head (3) comprises a frame (12) pivotably supported on the swivel axis (I), and wherein
abutment of the frame (12) with a component part (9, 15) which is constrained to the
handle (2) with respect to rotation about the swivel axis (I) limits pivoting of the
head (3) relative to the handle (2) about the swivel axis (I).
12. The hair removal device according to claim 11, wherein the component part (9, 15)
which is constrained to the handle (2) with respect to rotation about the swivel axis
(I) is a head part with an opening receiving a drive shaft of the transmission, wherein
at least one stop face (16) made from the second plastic material is provided on the
head part (9, 15).
13. The hair removal device according to claims 7 and 12, wherein the at least two levers
(8a, 8b) are pivotably hinged to the head part (15) or a further base plate (9) which
is constrained to the head part (15).
14. The hair removal device according to claim 13, wherein the further base plate (9)
comprises two arms (10), wherein each arm (10) comprises one of the swivel bearings
(11).
15. The hair removal device according to any of the preceding claims, wherein the at least
one hair removal unit (4, 5) of the head (3) comprises a foil-type upper cutter and
a lower cutter with several blades, wherein the transmission is coupled to the lower
cutter for driving the lower cutter in a translational movement relative to the upper
cutter.