[0001] The invention relates to a laundry treating machine (e.g. a laundry washing machine,
a laundry drier, a laundry washer/drier) comprising an opening giving access to an
inner space of the machine and a door to open and close said opening.
[0002] EP 2 434 046 discloses a laundry treating machine comprising a door to open and close an inner
space of the machine, wherein the door comprises at least one frame and at least one
transparent window held by the frame. The transparent window allows to inspect the
inner space when the door is closed. The door also comprises at least one intransparent
cover element adapted to partially conceal a region of the inner space, so that only
a part of the inner space is inspectable from the outside when the door is closed.
[0003] It is an object of the invention to provide a laundry treating machine with an alternative
design for avoiding or altering visibility of parts of the inner space.
[0004] It is another object of the invention to provide a laundry treating machine with
an improved design, which enables to avoid or alter the visibility of parts of the
inner space in an easy, effective and economical way.
[0005] The Applicant found that the above objects are achieved by a laundry treating machine
with a door comprising a cover element made of a transparent material with a knurled
portion. In this way only a part of the inner space of the machine (e.g. a treating
chamber with the laundry to be treated) is inspectable from the outside when the door
is closed, other (e.g. unaesthetical) parts of the inner space being concealed by
the knurled portion of the cover element.
[0006] The use of a cover element made of a transparent material, which is in part knurled,
is advantageous in that no additional components are required in order to achieve
the above objects of the invention. In addition, such a cover element can be obtained
by a single manufacturing step by using a suitable mold configured to provide the
partial knurling so that additional manufacturing steps are required, neither. In
this way, visibility of parts of the inner space is avoided or altered in an easy,
effective and economical way.
[0007] In a first aspect the present invention relates to a laundry treating machine comprising
an opening giving access to an inner space of the laundry treating machine and a door
to open and close said opening, the door comprising, from an outer side to an inner
side of the machine, an outer frame, a cover element, a transparent window and an
inner frame, wherein the cover element is made of a transparent material with a knurled
portion, so as to avoid or alter visibility of parts of the inner space from the outside
when the door is closed.
[0008] In the present description and claims, the terms "concealing" and "hiding" refer
both to the case wherein visibility of parts of the inner space is avoided and the
case wherein the visibility is altered in such a way that said parts are hardly visible
from the outside of the machine.
[0009] In the present description and claims, the terms "outer" and "inner" are used with
reference to the laundry treating machine, when the door is in a closed position.
Preferably, the outer frame protrudes outward with respect to the cover element, in
at least a peripheral portion of the door.
[0010] The laundry treating machine comprises a casing with a front wall, the opening being
preferably formed into said front wall.
[0011] The knurled portion is integral to the cover element. In this way, visibility of
parts of the inner space of the machine is avoided or altered without requiring additional
components.
[0012] The inner space of the laundry treating machine comprises a laundry treating chamber
for housing the laundry to be treated.
[0013] Preferably, the outer frame and/or the inner frame is opaque, i.e. substantially
intransparent to light.
[0014] Preferably, the knurled portion is positioned in the cover element so as to avoid
or alter visibility of parts of the inner space besides those parts concealed by the
outer frame and/or by the inner frame.
[0015] Preferably, the knurled portion is positioned in the cover element so as to hide
part of the transparent window.
[0016] Preferably, the knurled portion forms a rough surface. Preferably, the knurled portion
has a knurled pattern with peaks and valleys. The knurled pattern can have a series
of parallel, or criss-cross, substantially straight peaks and valleys that can extend
in any direction. In another embodiment, the peaks and valleys could be (semi)circular
and, preferably, concentric. In another embodiment, the knurled portion is sandblasted.
In a further embodiment, the knurled portion is formed by printing, in particular
screen printing.
[0017] Preferably, the transparent material of the cover element maintains its transparency
at the knurled portion with an altered (reduced) transparency level. This improves
the aesthetical appearance of the machine because the knurled portion keeps unaesthetical
parts hidden from view without being too showy. When the knurled portion is formed
by printing, in particular screen printing, it is preferred to use an ink or an amount
of ink, which alters the surface transparency to light without making such surface
completely light intransparent. Alternatively, the ink, or the amount of ink, may
make intransparent to light the surface on which the ink is deposed but the distribution
of such ink, i.e. the pattern defined by the ink deposition, is not uniform so as
to define light transparent areas surrounded by light intransparent areas.
[0018] The knurled portion could have any suitable shape and can be positioned in the cover
element in any position, depending upon the parts to be concealed in the inner space
of the machine, beside the parts already concealed by the outer frame and/or by the
inner frame. In an embodiment, the knurled portion substantially has a shape of a
segment of a circle. In another embodiment, the knurled portion could be ring shaped.
In an embodiment wherein the machine is of the front-loading type, the knurled portion
is in a lower region of the cover element. In an embodiment, the knurled portion substantially
has a shape matching the shape of a region (e.g. lower region) of the cover element.
[0019] Preferably, the knurled portion is in an inner surface of the cover element, facing
the transparent window of the door. In this way the outer surface of the cover element,
on the outside of the machine, can be made smooth. This can improve the aesthetical
appearance, the cleanability and the cleanliness of the door. In fact, as the knurled
portion rests in an inner, not accessible, part of the door, such portion is poorly
subject to dust. In addition, there is no risk that liquid droplets may drops onto
the knurled portion, resting there until they evaporate.
[0020] The shape of the opening can be circular, oval, rectangular, etc.
[0021] The shape of the door can be circular, oval, rectangular, etc.
[0022] The shape of the cover element preferably matches the shape of the door. For example,
it can be circular, oval, rectangular, etc..
[0023] The outer and inner frame can be circular, oval, rectangular, etc. In case of a circular
or oval door, they preferably have a substantially ring-shaped design. Preferably,
the door is shaped and sized so as to cover the opening. The door is advantageously
wider than the opening.
[0024] Preferably, the shape of the door matches at least in part the shape of the opening.
In an embodiment, the opening and the door could be in part shaped and/or sized differently.
This can happen, for example, in a laundry drier wherein the inner space of the machine
comprised between laundry treating chamber and the inner wall of the door is provided
with a lint filter that faces a region of the door. In this case, part of the door
made with a see-through, i.e. transparent, material may face both the opening and
part of the lint filter, together with an area surroundings the lint filter.
[0025] For example, the door can be substantially circular or oval and the opening can be
substantially dome shaped. According to another example, the door and the opening
can be substantially rectangular and coaxially arranged, the opening having a lower
height with respect to the door.
[0026] In a preferred embodiment, the knurled portion is positioned in the cover element
so as to avoid or alter visibility of an outline portion of the opening which is spaced
apart from an outline portion of the door.
[0027] Preferably, the opening outline is provided with a gasket for ensuring airtight closure
of the door, the knurled portion being positioned in the cover element so as to avoid
or alter visibility of a portion of the gasket positioned at said outline portion
of the opening, which is spaced apart from said outline portion of the door. This
is particularly advantageous when the opening and the door are shaped and/or sized
differently and, in particular, when the extent of the door is wider than the extent
of the opening, so that an outer and/or inner frame of the door would be not sufficient
to conceal said outline portion of the opening without extending the outer and/or
inner frame too much within a door see-through area.
[0028] In an embodiment, the transparent material of the cover element can be provided with
a plurality of knurled portions.
[0029] In a preferred embodiment, the transparent window has at least one knurled portion,
this knurled portion being in an outer surface of the transparent window facing the
cover element.
[0030] Preferably, the knurled portion of the cover element faces at least part of the knurled
portion of the transparent window.
[0031] Preferably, the knurled portion of the cover element has knurled pattern oriented
differently from the knurled pattern of the knurled portion of the transparent window.
This advantageously enables to improve hiding, or altering the view of, the parts
concealed both by the knurled portion of the cover element and the knurled portion
of the transparent window.
[0032] In an embodiment, the machine comprises a lint filter in a region of the inner space.
The lint filter can be positioned so as to face a region of the door. In this embodiment,
the knurled portion of the cover element is preferably positioned at said region of
the door so as to face at least part of the lint filter, which is thus hidden or hardly
visible. In this embodiment, if present, the knurled portion of the transparent window
is preferably positioned at said region of the door so as to face at least part of
the lint filter, which is thus hidden or hardly visible. Lint filter hiding is improved
when both the knurled portion of the transparent window and the knurled portion of
the cover element are exploited.
[0033] Preferably, the transparent window is made of glass. In an alternative embodiment
the transparent window can be made of plastic.
[0034] Preferably, the transparent material of the cover element is plastic.
[0035] Preferably, the transparent window and the cover element are separated by a gap in
an area that may be touched by a user. In that way, an air spacing is formed which
avoids overheating of the cover element which can be touched by the user. This advantageously
enables to avoid accidental burns of the user during high temperature cycles.
[0036] Preferably, the outer frame and/or inner frame are made in plastic, preferably opaque,
i.e. substantially intransparent to light. Preferably, each of them is molded as a
single piece of plastic.
[0037] The cover element and the transparent window are sandwiched between the outer frame
and the inner frame.
[0038] Preferably, the outer frame and the inner frame fix the cover element and the transparent
window to one other. In an alternative embodiment the door comprises a finishing rim
arranged outside the outer frame. Such finishing rim may have decorative and structural
functions.
[0039] Preferably, the inner frame protrudes inward with respect to the transparent window.
[0040] In an embodiment, the cover element is removably attached to the outer frame.
[0041] In another embodiment, the cover element is integral to the outer frame.
[0042] In an embodiment, the transparent window is fixed to the inner frame by connection
means, wherein the connection means are preferably a gluing, a welding, a screw connection
or a snap connection according to the material used for realizing the transparent
window.
[0043] In another embodiment, the transparent window is integral to the inner frame.
[0044] In a preferred embodiment,
- the outer frame comprises a plurality of coupling elements for the coupling to the
inner frame; and
- the inner frame includes a plurality of coupling counter-elements engaging with said
coupling elements of said outer frame.
[0045] Alternatively, coupling elements may be arranged on a finishing rim which is positioned
outside the outer frame. Such finishing is coupled with the inner frame through coupling
counter-elements formed on the inner frame.
[0046] In order to couple the outer frame to the inner frame, many different coupling elements
and coupling counter-elements could be used. For example, the coupling elements could
be screws and the counter-elements could be appropriate receptacles with a corresponding
screw thread. Other coupling elements could include bolts, plastic fasteners, snap-in
fasteners or the like, rivet coupling, etc. The counter-coupling elements could be
the receptacles or seats to fasten with the corresponding coupling elements.
[0047] In a preferred embodiment, the door includes a handle and, further preferably, the
handle is arranged on a handle-carrying element interposed between said inner frame
and said outer frame. Preferably, the handle-carrying element is configured to be
mounted in said door in a plurality of alternative positions, so that said handle
can be positioned along the door frame at different locations. This enables the user
to position the handle in the location most comfortable for the user to grasp, depending
on the positioning of the laundry treating machine.
[0048] The laundry treating machine can be a laundry washing machine, a laundry drier or
a laundry washer/drier.
[0049] These and other features and advantages of the invention will better appear from
the following description of some exemplary and non-limitative embodiments, to be
read with reference to the attached drawings, wherein:
- figure 1 shows a perspective view of a laundry treating machine according to an embodiment
of the invention;
- figure 2 shows a longitudinal section of the laundry treating machine of figure 1;
- figure 3 shows an enlarged view of a bottom region of the longitudinal section of
figure 2;
- figure 4 shows a front view of a door of the laundry treating machine of figure 1;
- figure 5 shows a sectional view of the door of figure 4, taken along line c-c of figure
4;
- figure 6 shows an enlarged view of the encircled portion of figure 5;
- figure 7 shows a perspective rear view of a cover element of the door of figure 4,
as seen from the right;
- figure 8 shows a rear view of the cover element of figure 7;
- figure 9 shows a sectional view of the cover element of figure 8, taken along line
A-A of figure 8;
- figure 10 shows an enlarged view of the encircled portion of figure 9,
- figure 11 shows a perspective view of a transparent window, as seen from the left,
of the door of figure 4.
[0050] In the figures a laundry treating machine 1 according to an embodiment of the invention
is shown.
[0051] The laundry treating machine 1 shown in the figures is a laundry drier. However it
is clear that the laundry treating machine can also be a laundry washing machine or
a laundry washer/drier. In particular, the machine 1 shown in the drawings is a front-loading
dryer. However, the invention can be applied also to top-loading washing and/or drying
machines having a drum rotating about a vertical, horizontal or inclined axis.
[0052] The laundry treating machine 1 comprises an outer casing 2, preferably but not necessarily
parallelepiped-shaped.
[0053] The casing 2 comprises an inner space with a treating chamber for housing the laundry
to be treated. In the embodiment shown of a laundry drier, the treatment chamber is
a drum 3, optionally perforated, having, for example, the shape of a hollow cylinder.
[0054] In an embodiment (not shown) wherein the laundry treating machine 1 is a laundry
washer or washer/drier, the treatment chamber preferably is a drum, optionally perforated,
which is rotatably contained in a tub.
[0055] With reference to figures 1 and 2, casing 2 generally includes a front wall 21, a
rear wall panel 25, a top panel 22, two sidewall panels 23 (only one visible in figure
1) all mounted on a basement 24. Elements 21, 22, 23, 24, 25 can be of any suitable
material.
[0056] Laundry treating machine 1 can comprise an electrical motor assembly (not shown)
for rotating, on command, revolving drum 3 along its axis inside casing 2. Casing
2, revolving drum 3 and electrical motor are common parts in the technical field and
are considered to be known; therefore they will not be described further in details.
[0057] Access to the drum 3 for laundry loading/unloading is achieved via an opening 4 formed
on the casing 2 itself, into the front wall 21.
[0058] Opening 4 preferably faces drum 3. Opening 4 is apt to be closed by a door 5. Opening
4 has an outline provided with a gasket 8 for ensuring airtight closure of the door
5.
[0059] The door 5 is configured to open and close the opening 4 and is advantageously pivotally
mounted, for example hinged, to the front wall 21 of the casing 2.
[0060] With reference to figure 1, 4 and 5, door 5 can be operated by a handle 6 attached
to the door itself. As visible in figure 5, the handle 6 is preferably provided with
reinforcing ribs. Besides strengthening the handle 6, the reinforcing ribs also enable
to improve the grip on the handle 6 because they avoid slipping of the hand, especially
a wet hand as may well occur when dealing with washing laundry.
[0061] As shown in detail in figures 3 and 4, door 5 comprises, from an outer side to an
inner side of the machine 1, an outer frame 52, a cover element 54, a transparent
window 55 and an inner frame 56.
[0062] As shown in the figures, the door 5 may also optionally comprise a finishing rim
51 (e.g. for decorative purposes), which is positioned outside the outer frame 52,
and a handle-carrying element 53 interposed between the outer frame 52 and the cover
element 54.
[0063] In the embodiment shown, the door 5 is substantially circular. The cover element
54 is substantially a solid disc. The transparent window 55 is generally circular
with a lower portion 552 (depicted in figures 5 and 11) protruding towards the inner
of the laundry treating machine 1, in a way conventional in the art. The outer frame
52, the inner frame 56, the finishing rim 51 and the handle-carrying element 53 are
substantially annular.
[0064] The cover element 54, the transparent window 55, the outer frame 52, the inner frame
56, the finishing rim 51 and the handle-carrying element 53 have an annular flange
with coupling means configured to couple and/or centre them to each other. The cover
element 54 is made, in at least a central region thereof, of transparent material
such as, for example, transparent plastic.
[0065] Preferably, the transparent window 55 is made of glass. In an alternative embodiment
(e.g., for low cost and/or low temperature applications), the transparent window can
be made of plastic.
[0066] Preferably, the outer frame 52, the inner frame 56, the finishing rim 51 and the
handle-carrying element 53 are made in plastic, preferably opaque, i.e. substantially
intransparent to light. The finishing rim 51 may also be made in metal or in plastic
with a metal surface.
[0067] The cover element 54 and the transparent window 55 are sandwiched between the outer
frame 52 and the inner frame 56 via coupling elements and coupling counter-elements
60 formed on the outer frame and inner frame respectively, so as to be engaged one
with the other. If a finishing rim 51 is provided outside the outer frame 52, as shown
in the figures, coupling elements 59 may be formed on such finishing rim 51 instead
of the outer frame 52.
[0068] The outer frame 52 and the inner frame 56 fix the cover element 54 and the transparent
window 55 to one other.
[0069] The outer frame 52 protrudes outward with respect to the cover element 54.
[0070] In an embodiment, the cover element 54 is removably attached to the outer frame 52.
In another embodiment, the cover element 54 is integral to the outer frame 52. Preferably,
the inner frame 56 protrudes inward with respect to the transparent window 55. In
an embodiment, the transparent window 55 is fixed to the inner frame 52 by connection
means. For example, when the transparent window 55 is made of glass, the connection
means are preferably a gluing or a snap connection. In case of plastic, the connection
means preferably are a gluing, a welding, a screw connection or a snap connection.
[0071] When the transparent window 55 is made of plastic, it can be made integral to the
inner frame 56.
[0072] Preferably, the transparent window 55 and the cover element 54 are separated by a
gap 57 (depicted in figure 5) in an area that may be touched by a user. In that way,
air spacing 57 is formed which avoids overheating of the cover element 54 which can
be touched by the user. This advantageously enables to avoid accidental burns of the
user during high temperature cycles.
[0073] The transparent cover element 54 and the transparent window 55 form in the door 5
a see-through area that allows inspecting at least part of the inner space of the
laundry treating machine 1 when the door 5 is closed. Advantageously, the see-through
area enables to inspect the drum 3 so that loaded laundry is visible to the user.
[0074] As visible in figures 2 and 3, the laundry treating machine preferably further comprises
a lint filter 7. In the embodiment shown wherein the machine 1 is a front-loading
dryer, the lint filter 7 is positioned below the opening 4, in a lower region 70 of
the inner space of the machine 1, between a lower region 30 of the drum 3 and a lower
region 50 of the door 5.
[0075] It is observed that in the embodiment shown wherein the machine 1 is a front-loading
dryer, the terms "lower" and "upper" referred to parts/regions of the machine 1 are
used with reference to the median transversal plane B-B (shown in figure 2) of the
machine 1.
[0076] The lint filter 7 rests at the bottom of the opening 4. The upper edge of the lint
filter 7 defines a lower outline of the opening 4 which is spaced apart from the lower
outline of the door 5. Indeed, the opening 4 and the door 5 are of substantially the
same shape and size in an upper region 58 of the door 5 and of a different shape and
size in the lower region 50of the door 5 where the extent of the door 5 is wider than
the extent of the opening 4. In particular, in the embodiment shown, the door 5 is
substantially circular while the opening 4 is substantially dome shaped. Therefore,
the lint filter 7 and the area surroundings the lint filter 7, below the opening 4,
as well as a lower portion of the gasket 8 (positioned at the lower outline of the
opening 4) face the lower region 50of the door 5 that is made with a see-through (i.e.
transparent) material. These parts may thus be visible from the outside of the laundry
treating machine 1, when the door 5 is closed, and spoil the aesthetical appearance
of the laundry treating machine 1 itself.
[0077] In order to conceal said unaesthetical parts with the outer frame 52 and inner frame
56 of the door 5, which are made of intransparent material, the frames 52, 56 would
need to extend too much over the see-through area of the door 5, whereby said see-through
area would be too limited.
[0078] According to the invention, said unaesthetical parts are thus made hardly visible
by providing the transparent material of the cover element 54 with a knurled portion
540.
[0079] In the embodiment shown in the figures, the knurled portion 540 is in a lower region
542 of the cover element 54 and substantially has a shape of a segment of a circle
matching the shape of the lower region 542 of the cover element 54.
[0080] As visible in figure 6, the knurled portion 540 preferably is in an inner surface
of the cover element 54, facing the transparent window 55 of the door 5. As stated
above, in this way the outer surface of the cover element 54, on the outside of the
machine 1, can be made smooth thereby improving the aesthetical appearance, the cleanability
and the cleanliness of the door 5.
[0081] As visible in figures 6 and 10, the knurled portion 540 forms a rough surface having
a knurled pattern with a series of parallel substantially straight peaks and valleys
that extend in a horizontal direction.
[0082] In a preferred embodiment, visible in figures 3, 5, 6 and 11, also the transparent
window 55 has a knurled portion 550. The knurled portion 550 is preferably positioned
at the lower region 552 of the transparent window 55, in an outer surface facing the
cover element 54, on the opposite side of the drum 3. This prevents the laundry loaded
into the drum 3 from coming into contact with the knurled portion 550 and being thus
damaged.
[0083] Preferably, the knurled portion 540 of the cover element 54 faces at least part of
the knurled portion 550 of the transparent window 55. In addition, the knurled portion
540 of the cover element 54 preferably has a knurled pattern oriented differently
from the knurled pattern of the knurled portion 550 of the transparent window 55.
This advantageously enables to improve the hiding effect obtained by the combination
of the two knurled portions 540, 550. For example, in the embodiment shown in the
figures, the knurled portion 540 has a series of parallel substantially straight peaks
and valleys that extend in a horizontal direction while the knurled portion 550 has
a series of parallel substantially straight peaks and valleys that extend in a vertical
direction. As they extend in a vertical direction, the straight peaks and valleys
of knurled portion 550, facing the horizontal straight peaks and valleys of knurled
portion 540, are not visible in figure 6.
[0084] In the embodiment shown in the figures, the knurled portion 550 is advantageously
positioned at the lower region 552 of the transparent window 55 so as to face at least
part of the lint filter 7, which is thus hidden or made hardly visible from the outside
of the machine 1, when the door 5 is closed. Lint filter 7 hiding is improved thanks
to the double action of both the knurled portion 550 of the transparent window 55
and the knurled portion 540 of the cover element 54.
1. Laundry treating machine (1) comprising an opening (4) giving access to an inner space
of the laundry treating machine (1) and a door (5) to open and close said opening
(4), the door (5) comprising, from an outer side to an inner side of the machine (1),
an outer frame (52), a cover element (54), a transparent window (55) and an inner
frame (56), wherein the cover element (54) is made of a transparent material with
a knurled portion (540), so as to avoid or altering visibility of parts of the inner
space from the outside when the door (5) is closed.
2. Laundry treating machine (1) according to claim 1, wherein the outer frame (52) and/or
the inner frame (56) is opaque, the knurled portion (540) being positioned in the
cover element (54) so as to avoid or alter visibility of parts of the inner space
besides those parts concealed by the opaque outer frame (52) and/or opaque inner frame
(56).
3. Laundry treating machine (1) according to claim 1 or 2, wherein the knurled portion
(540) has a knurled pattern with peaks and valleys.
4. Laundry treating machine (1) according to any of claims 1 to 3, wherein the knurled
portion (540) is in a inner surface of the cover element (54), facing the transparent
window (55) of the door (5).
5. Laundry treating machine (1) according to any of claims 1 to 4, wherein the opening
(4) and the door (5) are in part shaped and/or sized differently.
6. Laundry treating machine (1) according to any of claims 1 to 5, wherein the knurled
portion (540) is positioned in the cover element (54) so as to avoid or alter visibility
of an outline portion of the opening (4) which is spaced apart from an outline portion
of the door (5).
7. Laundry treating machine (1) according to claim 6, wherein the opening (4) has an
outline provided with a gasket (8) for ensuring airtight closure of the door (5),
the knurled portion (540) being positioned in the cover element (54) so as to avoid
or alter visibility of a portion of the gasket (8) positioned at said outline portion
of the opening (4), which is spaced apart from said outline portion of the door (5).
8. Laundry treating machine (1) according to any of claims 1 to 7, wherein the transparent
window (55) has a knurled portion (550) in an outer surface of the transparent window
(55), facing the cover element (54).
9. Laundry treating machine (1) according to claim 8, wherein the knurled portion (540)
of the cover element (54) faces at least part of the knurled portion (550) of the
transparent window (55).
10. Laundry treating machine (1) according to claim 8 or 9, wherein the knurled portion
(540) of the cover element (54) has knurled pattern oriented differently from the
knurled pattern of the knurled portion (550) of the transparent window (55).
11. Laundry treating machine (1) according to any of claims 1 to 10, wherein the machine
comprises a lint filter (7) arranged in a region (70) of the inner space.
12. Laundry treating machine (1) according to claim 11, wherein the knurled portion (540)
of the cover element (54) is positioned in a region (50) of the door (5) so as to
face at least part of the lint filter (7).
13. Laundry treating machine (1) according to claim 8 and 11, wherein the knurled portion
(550) of the transparent window (55) is positioned in a region (50) of the door (5)
so as to face at least part of the lint filter (7).
14. Laundry treating machine (1) according to any of claims 1 to 13, wherein the cover
element (54) and the transparent window (55) are sandwiched between the outer frame
(52) and the inner frame (56).
15. Laundry treating machine (1) according to any preceding claim comprising a finishing
rim (51) positioned outside the outer frame (52), coupling elements (59) being arranged
on said finishing rim (51) or on the outer frame (52) and coupling counter-elements
(60) being arranged on the inner frame (56) so as to be engaged with the coupling
elements (59).