[0001] The present invention relates to a porthole door for laundry washing machines and
to a household appliance provided with said porthole door.
[0002] More specifically, the present invention relates to a porthole door for a home front-loading
laundry washing machine, to which the following description refers purely by way of
example.
[0003] As is known, front-loading laundry washing machines normally comprise a substantially
parallelepiped-shaped outer box casing, which is provided with a substantially circular
laundry loading/unloading opening on the front face of the casing; and a porthole
door which is hinged to the front face of the casing, close to the peripheral edge
of the laundry loading/unloading opening, to rotate about a vertical axis to and from
a closing position, in which the peripheral edge of the door rests completely against
the front face of the casing to watertight seal the laundry loading/unloading opening.
[0004] The porthole door usually consists of a cup-shaped body which is made of annealed
transparent glass and has a flared outer peripheral edge; and of an annular porthole
bearing structure which is rigidly coupled to the outer peripheral edge of the cup-shaped
body and is hinged to the front face of the casing.
[0005] The annular porthole bearing structure consists of two separate annular frames which
are located, coaxial to the cup-shaped body, on opposite sides of the flared outer
peripheral edge of the cup-shaped body, and are rigidly coupled to one another via
screws or similar so to tightly clamp the outer peripheral edge of the cup-shaped
body.
[0006] The rear annular frame, i.e. the porthole annular frame which comes in abutment against
the front face of the casing when the door is placed in the closing position, is usually
made of metal material and is fixed in swiveling manner to the front face of casing
via a hinge; whereas the front annular frame is usually made of plastic material and
houses the handle allowing the user to manually unlock the door from the machine casing.
[0007] Despite being intrinsically highly safety, this kind of porthole door is relatively
expensive to produce because of the relative large size of the annealed-glass cup-shaped
body, and it is quite heavy thus requiring the use of oversized heavy-duty metal hinges.
To solve these drawbacks, in the recent years some household appliance manufacturers
replaced the annealed-glass cup-shaped body with a cup-shaped body made of transparent
plastic material.
GB20008624 and
US-2003/0110813 disclose this kind of plastic porthole doors.
[0008] Aim of the present invention is to provide a porthole door for laundry washing machines
which is cheaper to produce and lighter in weight than today's porthole doors with
a plastic cup-shaped body.
[0009] According to the present invention, there is provided a porthole door for laundry
washing machines as claimed in Claim 1 and preferably, though not necessarily, in
any one of the dependant Claims.
[0010] According to the present invention, there is also provided a household appliance
provided as claimed in Claim 15 and preferably, though not necessarily, in any one
of the dependent Claims.
[0011] A non-limiting embodiment of the present invention will be described by way of example
with reference to the accompanying drawings, in which:
Figure 1 shows a isometric view, with parts removed for clarity, of a front-loading
laundry washing machine provided with a porthole door realized in accordance with
the teachings of the present invention;
Figure 2 shows a larger-scale, partly-exploded isometric view of the Figure 1 porthole
door;
Figure 3 shows a section view of the Figure 2 porthole door; and
Figures 4 and 5 show two larger-scale, detailed views of the Figure 3 porthole door.
[0012] With reference to Figure 1, number 1 indicates as a whole a porthole door suitable
to be used in a household appliance provided with a porthole door, like a home front-loading
laundry washing and/or drying machine 2.
[0013] The laundry washing and/or drying machine 2 comprises a substantially parallelepiped-shaped
outer box casing 3, which is provided with a substantially circular laundry loading/unloading
opening 1a formed on its front face 4; and the porthole door 1 is hinged to the front
face 4 of casing 3, close to the peripheral edge of the laundry loading/unloading
opening 1a, to rotate freely about a preferably, though not necessarily, vertical
axis, to and from a closing position, in which the peripheral edge of the porthole
door 1 completely rests against the front face 4 of casing 3 and watertight seal opening
1a,
[0014] More specifically, porthole door 1 has a rear face 1r which abuts against the front
face 4 of casing 3 when the porthole door 1 is in the closing position, and a front
face 1f which faces the outside of casing 3 when the porthole door 1 is in the closing
position, and in the example shown it is connected in swiveling manner to casing 3
via a hinge 5 which is rigidly attached to front face 4, close to the peripheral edge
of the laundry loading/unloading opening 1a, so to let the porthole door 1 freely
rotate about a vertical axis A locally substantially tangent to front face 4.
[0015] Differently from the porthole doors used in today's front-loading laundry washing
machines, the porthole door 1 comprises a preferably, though not necessarily, circular,
substantially basin-shaped body 11 which is made of transparent or semi-transparent
plastic material, forms the front face 1f of the porthole door 1, and is provided
with an outer peripheral flange 11a having a substantially U-shaped transversal cross
section.
[0016] More specifically, with reference to Figures 2 and 3, the outer peripheral flange
11a forms part of the front face 1f of the porthole door 1, and ends with a preferably,
though not necessarily, cylindrical annular collar which is faced to, and spaced from,
the main annular lateral wall 11b of the basin-shaped body 11, so as to delimit, together
with the main annular lateral wall 11b of the basin-shaped body 11, an outer annular
seat 11' whose concavity faces the outer surface of the main annular lateral wall
11b. In other words, concavity of annular seat 11' faces the front face 4 of casing
3 when the porthole door 1 is placed in the closing position.
[0017] In addition to the above, the outer peripheral flange 11a is realized in one piece
with the basin-shaped body 11 via an injection molding process so as to form a unique
plastic shell 11 having a preferably, though not necessarily, constant thickness;
and the porthole door 1 also comprises an inner annular frame 12 which is made of
an opaque plastic material (i.e. a material not allowing light to pass through), and
is over-injected into the outer annular seat 11' of the basin-shaped body or shell
11 during the same injection molding process, immediately after the hardening of the
plastic material forming the basin-shaped body 11, so as to be permanently fixed to
the basin-shaped body or shell 11.
[0018] More specifically, the inner annular frame 12 is over-injected into the annular seat
11' of the basin-shaped body 11 within preferably, though not necessarily, 30 seconds
from the complete hardening of the plastic material forming the basin-shaped body
11. Obviously, the melting temperature of the plastic material forming the basin-shaped
body or shell 11 is higher than the melting temperature of the plastic material forming
the inner annular frame 12.
[0019] With reference to Figure 2, the inner annular frame 12 is structured for being directly
coupled to the hinge 5 connecting the porthole door 1 to the front face 4 of casing
3, and is preferably, though not necessarily, shaped so as to form a seat 5a for hinge
5.
[0020] In the example shown, the basin-shaped body or shell 11 is preferably, though not
necessarily, made of transparent polyester and/or polycarbonate; whereas the inner
annular frame 12 is preferably, though not necessarily, made of opaque polyester and/or
polystyrene and/or acrylonitrile-butadiene-styrene (commonly known as ABS).
[0021] With reference to Figures 1 and 2, the porthole door 1 optionally comprises also
an auxiliary annular cover 13 which is made of an opaque plastic material, and is
structured for covering up the annular seat 11' of the basin-shaped body 11 so to
completely hide the inner annular frame 12.
[0022] More specifically, in the example shown the auxiliary annular cover 13 is preferably,
though not necessarily, made of an opaque polyester and/or polycarbonate and is formed
separately from the inner annular frame 12 via a traditional injection molding process,
and is structure for being directly coupled and firmly anchored to the inner annular
frame 12 via a number of a snap-lock locking pins or tongues 14 realized on the inner
annular frame 12 and/or on the auxiliary annular cover 13. Clearly, in a different
embodiment, annular cover 13 may be firmly anchored to the inner annular frame 12
via metal screw, rivets, welding or gluing.
[0023] Preferably, though not necessarily, the porthole door 1 is finally provided with
a manually-operated door-lock device 15 which is structured for selectively lock the
porthole door 1 to the machine casing 3 when the porthole door 1 is in the closing
position.
[0024] With reference to Figure 2, in the example shown, the inner annular frame 12 is structured
for supporting the door-lock device 15, and the door-lock device 15 consists of a
hooked catch lever 16 which is fixed in swivelling manner to the inner annular frame
12 of porthole door 1, and protrudes from the inner annular frame 12 towards the front
face 4 of casing 3, extending through the auxiliary annular cover 13 if present, so
as to enter into a corresponding slot 16a realized in front wall 4, next to the laundry
loading/unloading opening 1a, and there firmly engage the machine casing 3; of a spring
mechanism (not shown) designed to keep the hooked catch lever 16 in a given rest position
allowing the distal end of catch lever 16 to hook on the edge of the machine casing
3, into the slot 16a in front wall 4; and of a manually-operated handle 17 which is
housed in a through opening 17a realized on the outer peripheral flange 11a of the
basin-shaped body or shell 11, and is fixed in swiveling manner to the inner annular
frame 12 so to selectively engage and tilt the hooked catch lever 16, overcoming the
elastic force of the spring mechanism.
[0025] In other words, the manually-operated handle 17 is able to selectively move the hooked
catch lever 16 away from the rest position, allowing the distal end of catch lever
16 to unlock the edge of the machine casing 3 when the porthole door 1 is placed in
the closing position. Thus, acting directly on handle 17, the user can manually release
the porthole door 1 from casing 3 and rotate the porthole door 1 about axis A.
[0026] Operation of porthole door 1 and laundry washing and/or drying machine 2 are clearly
inferable from the above description, with no further explanation required.
[0027] The production process of porthole door 1, in turn, comprises the step of injecting
a given quantity of a transparent or semi-transparent plastic material, into the first
mould inner cavity negatively reproducing the shape of the basin-shaped body 11, outer
peripheral flange 11a included, so as to form the whole basin-shaped body 11 via a
unique injection of plastic material; and the step of over-injecting, immediately
after the hardening of the plastic material forming the basin-shaped body 11, a given
quantity of an opaque plastic material, into a second mould inner cavity partly delimited
by the outer annular seat 11' of basin-shaped body 11 and negatively reproducing the
shape of the inner annular frame 12, so to form the inner annular frame 12 directly
inside the outer annular seat 11' of basin-shaped body 11.
[0028] The particular structure of porthole door 1 provides several advantages. First of
all, assembly of the porthole door 1 is significantly simplified because the inner
annular frame 12 is rigidly and permanently fixed to the basin-shaped body or shell
11 during the injection molding process, thus reducing production costs of the porthole
door.
[0029] Further the present structure provides a porthole door having an improved aesthetic
appearance. Such improved aesthetic effect is due to the peripheral flange 11a being
transparent or semi-transparent and forming the front face of the porthole door and
due to the inner annular frame 12 being opaque and forming the rear face of the peripheral
flange 11a. The contrast between the transparent peripheral flange 11a and the opaque
inner annular frame 12 in the background provides the aesthetic effect when the porthole
door, -in closed position-, is watched by the user.
[0030] Additionally, the present porthole structure allows manufacturing the transparent
shell body 11 with a relatively small thickness thereby reducing the amount of the
costly transparent material needed for its production since the inner annular frame
12 made of less costly opaque material provides the supporting function for the hinge
5 and the manually-operated door-lock device 15.
[0031] Moreover, production of basin-shaped body or shell 11 and inner annular frame 12
during the same injection molding process, give designers much more freedom to harmonize
the shape of the porthole door to that of the casing front face.
[0032] Clearly, changes may be made either to porthole door 1 or to laundry washing and/or
drying machine 2 as described herein without, however, departing from the scope of
the present invention.
[0033] For example, in case the melting temperature of the plastic material forming the
basin-shaped body or shell 11 is lower than the melting temperature of the opaque
plastic material forming the inner annular frame 12, the basin-shaped body 11 is over-inject
above the inner annular frame 12, immediately after the hardening of the plastic material
forming the inner annular frame 12.
[0034] In other words, since the plastic material having the higher melting temperature
is to be injected first, basin-shaped body 11 and inner annular frame 12 are still
made during the same injection molding process, but the injection sequence starts
with the injection, into the mould, of the plastic material forming the inner annular
frame 12. The plastic material forming the basin-shaped body or shell 11 is obviously
injected into the mould immediately after the complete hardening of the plastic material
forming the inner annular frame 12.
1. Porthole door (1) for laundry washing machines (2) and similar, having a rear face
(1r) which abuts against the machine casing (3) when the porthole door (1) is in the
closing position, and a front face (1f) which faces the outside of the machine casing
(3) when the porthole door (1) is in the closing position; the porthole door (1) being
characterized by comprising:
- a shell body (11) which is made of transparent or semi-transparent plastic material,
and is provided with an outer peripheral flange (11a) which defines part of the front
face (1f) of the porthole door (1), and is provided, on the rear-face side thereof,
of an annular seat (11'); and
- an inner annular frame (12) which is made of an opaque plastic material, and is
permanently fixed into the annular seat (11') formed by said outer peripheral flange
(11a);
the outer peripheral flange (11a) being realized in one piece with the rest of shell
body (11) via an injection molding process, so as to form a unique transparent or
semi-transparent plastic element (11); said unique transparent or semi-transparent
plastic element (11) and said inner annular frame (12) being over-injected one on
the other during the same injection molding process.
2. Porthole door as claimed in Claim 1, characterized in that the outer peripheral flange (11a) has a substantially U-shaped transversal cross
section.
3. Porthole door as claimed in Claim 1 or 2, characterized in that the shell body (11) is a substantially basin-shaped body (11).
4. Porthole door as claimed in any one of the foregoing Claims, characterized in that said inner annular frame (12) is over-injected into the annular seat (11') formed
by the outer peripheral flange (11a) of said shell body (11).
5. Porthole door as claimed in any one of the foregoing Claims, characterized in that said inner annular frame (12) is structured for being coupled to the hinge (5) connecting
the porthole door (1) to the casing (3) of the laundry washing machine (2) or similar.
6. Porthole door as claimed in Claim 5, characterized in that said inner annular frame (12) is shaped so as to form a seat (5a) for said hinge
(5).
7. Porthole door as claimed in any one of the foregoing Claims, characterized by also comprising an auxiliary annular cover (13) which is made of an opaque plastic
material, and is structured for covering up the annular seat (11') of the shell body
(11) so to hide the inner annular frame (12).
8. Porthole door as claimed in Claim 7, characterized in that said auxiliary annular cover (13) is structure for being directly coupled and firmly
anchored to the inner annular frame (12).
9. Porthole door as claimed in Claim 8, characterized in that said auxiliary annular cover (13) is structure for being firmly anchored to the inner
annular frame (12) via a number of a snap-lock locking means (14) realized on the
inner annular frame (12) and/or on the auxiliary annular cover (13).
10. Porthole door as claimed in any one of the foregoing Claims, comprising a manually-operated
door-lock device (15) which is structured for selectively lock the porthole door (1)
to the casing (3) of the laundry washing machine (2) or similar, characterized in that said inner annular frame (12) is structured for supporting said manually-operated
door-lock device (15).
11. Porthole door as claimed in Claim 10,
characterized in that said manually-operated door-lock device (15) comprises
- a hooked catch lever (16) which is fixed in
swivelling manner to the inner annular frame (12) of the porthole door (1), and protrudes
from the inner
annular frame (12) towards the casing (3) of the laundry washing machine (2) or similar,
so as to enter into a corresponding slot (16a) realized in said casing (3);
- a spring mechanism designed to keep the hooked catch lever (16) in a given rest
position allowing the distal end of the hooked catch lever (16) to hook on the edge
of the casing (3) of the laundry washing machine (2) or similar, into the slot (16a)
on said casing (3); and
- a manually-operated handle (17) which is housed in a through opening (17a) realized
on the outer peripheral flange (11a) of the shell body (11), and is fixed in swiveling
manner to the inner annular frame (12) so to selectively engage and tilt the hooked
catch lever (16), overcoming the elastic force of the spring mechanism.
12. Porthole door as claimed in any one of the foregoing Claims, characterized in that the shell body (11) is made of a transparent polyester and/or polycarbonate.
13. Porthole door as claimed in any one of the foregoing Claims, characterized in that the inner annular frame (12) is made of opaque polyester and/or polystyrene and/or
acrylonitrile-butadiene-styrene.
14. Household appliance (2) comprising a substantially parallelepiped-shaped outer box
casing (3) which is provided with a main opening (1a) on its front face (4), and a
porthole door (1) which is hinged to the front face (4) of the casing (3), close to
the peripheral edge of said main opening (1a), to rotate about a reference axis to
and from a closing position in which the peripheral edge of the porthole door rests
against the front face (4) of the casing (3) to seal said main opening (1a); the household
appliance (2) being characterized in that said porthole door (1) is a porthole door as claimed in anyone of Claims 1-14.
15. Household appliance as claimed in Claim 15, characterized in that of being a laundry washing and/or drying machine (2).