EP4640937A1

EP4640937A1 - Drum for laundry machine, laundry dryer, washer dryer or similar appliances

Info

Publication number: EP4640937A1
Application number: EP25164808.5A
Authority: EP
Inventors: Pietro Quagliarello; Fabio Beretta; Fabrizio INVERNIZZI; Sergio Ronchi; Jacopo Carminati; Andrea Zenaro; Antonio ACRI
Original assignee: Candy SpA
Current assignee: Candy SpA
Priority date: 2024-04-23
Filing date: 2025-03-19
Publication date: 2025-10-29

Abstract

A laundry drum (7) for a washing machine (1) with a rear wall (9), a front wall (10) and a side wall (8) extending about a rotation axis (6) of at least the side wall (8) of the drum (7), and defining an inner space (11) for containing laundry, a plurality of blade mounting seats (14) formed in the side wall (8) in the form of through apertures to accommodate corresponding coupling members (15) of one or more dragging blades (13) mountable in the drum (7), and a plurality of protective protuberances (16) protruding outwards from the side wall (8) and positioned beside each of said blade mounting seats (14), respectively, in a circumferential rotation direction (25) of the side wall (8).

Description

The present invention relates to a laundry drum for a washing machine, a washer dryer or a tumble-dryer.
The term drum indicates both embodiments with a perforated side wall, sometimes referred to as "laundry baskets", and embodiments with a non-perforated side wall, frequently referred to as "laundry drums".
With particular reference to known washing machines, the drum, e.g., perforated, intended to accommodate the laundry to be washed, is rotatably arranged inside a tank containing the lye. Thanks to the rotational movement of the drum, the laundry is agitated and swirled in the lye and the lye itself is dragged upwards by the rotating drum from where it falls on the laundry, which is completely soaked and softened, so as to transfer the impurities to the washing and rinsing lye.
The drum usually consists of a rear wall by means of which the drum is fixed into the washing machine, a front wall which delimits a loading opening through which it is possible to access the inside of the drum, and a generally cylindrical and possibly perforated side wall to allow the exchange of lye between the tank and the inside of the drum. The side wall is usually obtained from a steel sheet with two opposite longitudinal edges and two opposite transverse edges, which is bent about a longitudinal axis of the drum to form such a cylinder and the transverse edges of which are connected to each other to maintain the cylindrical shape, while the longitudinal edges are connected to respective outer edges of the rear and front walls to form the drum.
There are also known laundry drums in which the side, rear and front walls are not connected to one another to rotate in unison as a single body, but in which the side wall is configured to rotate about a rotation axis, while the rear and/or front wall can be stationary.
The walls of the laundry drums can be made of sheet metal, e.g., steel, or of synthetic polymer material.
In order to increase the washing and drying performance of the laundry contained in the drum, it is known to equip the drum with one or more dragging blades positioned on the inside of the side wall, in order to improve the lifting of the laundry and the lye during the rotation of the drum.
The dragging blades are made of polymer material by injection molding, separately from the side wall of the drum, and then mounted to the side wall by mechanically coupling the dragging blade coupling members to respective counter-coupling seats on the side wall of the drum.
The dragging blade coupling members extend through the side wall of the drum and protrude radially outward therefrom.
In the case of small, hard and relatively heavy objects (e.g., coins or buttons that have become lodged in the seal between the drum and the tank), during the spin cycle or intense rotation of the drum, the hard objects are lifted from the bottom of the tank and violently hit against the plastic coupling members protruding from the rotating drum, breaking the coupling members and damaging the dragging blades.
It is the object of the invention to provide a laundry drum (intended as a general name for laundry drums and baskets with perforated or non-perforated side walls) of the type described in the introduction, improved so as to reduce the risk of breakage of the dragging blade coupling members.
This object is achieved by a laundry drum for a washing machine or washer dryer or tumble-dryer, comprising:

a rear wall,
a front wall opposite to the rear wall,
a side wall extending about a longitudinal axis which constitutes the rotation axis of at least the side wall of the drum, and which is connected to or borders with the rear and front walls to delimit an inner space of the drum,
a plurality of blade mounting seats formed in the side wall in the form of through apertures to accommodate corresponding coupling members of a dragging blade,

Protective protuberances protect the coupling members from impacts from hard objects, allowing them to be made from materials and with dimensions that are sufficiently resistant for their function of mounting the dragging blades, but not necessarily resistant to violent impacts.
The features and advantages of the present invention will become more apparent from the following detailed description of some exemplary, non-limiting embodiments, shown in the accompanying drawings, in which:

Figure 1 is a perspective view of a laundry drum according to an embodiment,
Figure 2 shows a region of a side wall of the drum in Figure 1, for mounting a dragging blade, according to an embodiment,
Figure 3 shows a detail of a side wall of a laundry drum, seen from the outside of the laundry drum, with blade mounting seats and with protective protuberances, according to an embodiment,
Figure 4 shows the same side wall region as shown in Figure 3, with the coupling members inserted and engaged with the blade mounting seats,
Figure 5 is a perspective view of an inner region of a laundry drum, with blade mounting seats, according to an embodiment,
Figure 6 is the same view as Figure 5, but with a dragging blade mounted on the side wall of the drum,
Figure 7 is a section view of a side wall of the laundry drum, with blade mounting seats, according to a section plane orthogonal to a rotation axis of the laundry drum,
Figure 8 shows a household appliance for treating laundry, e.g., a washing machine, a washer dryer, or a tumble-dryer comprising a laundry drum (hidden here by the outer housing of the appliance),
Figure 9 is a section view of a blade mounting seat, a blade coupling member and a drum protection protuberance according to an embodiment.

Description of embodiments

With reference to the figures, Figure 8 shows a washing machine 1, with a housing 2 inside which a tank 3 is housed, consisting of a body, e.g., generally cylindrical or hollow, made of plastic or stainless steel. The tank 3 is coupled to the housing 2 by known means, comprising for example shock absorbers and suspension springs.
The tank 3 forms an opening 4 closable by a door 5. A drum 7 for accommodating the laundry to be washed and/or dried is housed, rotatably about a rotation axis 6, inside the tank 3. The drum 7 comprises a side wall 8, a rear wall 9 and a front wall 10. The walls 8, 9, 10 delimit an inner space 11 for accommodating the laundry to be washed and/or dried. The front wall 10 can be a stainless steel or plastic ring, with an opening 12, for example circular in shape, placed at the opening 4 of the tank 3, for accessing the inner space 11 in order to load and unload the laundry.
The rear wall 9 of the drum 7 can comprise a substantially flat, centrally drawn, steel disc with concavity facing the outside of the drum. Centrally to the rear wall 9, a support hub can be mounted for rotatably supporting the drum 7 with respect to the tank 3 or the support structure of the appliance 1 and connecting the drum 7 to a motor (directly or via a transmission) to drive the drum 7 in rotation.
The side wall 7 of the drum is preferably obtained from a flat steel sheet, which is bent to form a surface approximately of rotation about a longitudinal central axis, in use coinciding with the rotation axis 6.
The coupling of the bottom walls 8 and front walls 9 to the side wall 7 can be achieved by folding two end segments of the sheet metal forming the side wall 8, so as to give the steel sheet, at the two ends thereof, a C-shaped profile. The rear walls 9 and front walls 10 are shaped so as to define, at the respective outer edges, profiles complementary to the C-shaped profile formed at the two end segments of the side wall 8.
The drum 7 further comprises one or more, for example three, dragging blades 13 arranged on the side wall 8 and protruding into the inner space 11 of the drum 7.
According to an aspect of the invention, the drum 7 comprises a plurality of blade mounting seats 14 formed in the side wall 8 in the form of through apertures for accommodating corresponding coupling members 15 of a dragging blade 13, as well as a plurality of protective protuberances 16 protruding radially outwards from the side wall 8 (with reference to the rotation axis 6 of the side wall 8) and positioned adjacent to each of said blade mounting seats 14, respectively, in a circumferential rotation direction 25 of the side wall 8.
The protective protuberances 16 protect the coupling members 15 from impacts from hard objects, e.g., coins, buttons, etc., allowing the coupling members 15 to be made from materials and with dimensions that are sufficiently resistant for their function of mounting the dragging blades 13, but not necessarily resistant to violent impacts.

Description of the blade mounting seats 14

According to an embodiment, each of the blade mounting seats 14 is delimited by an edge 17 of cut metal sheet or injection molded plastic wall, which delimits an enlarged through opening zone 18 and an adjacent and communicating narrowed through opening zone 19 of reduced width with respect to the enlarged through opening zone 18. The through opening zone 18 can be substantially rectangular. The narrowed through opening zone 19 can be, for example, a linear slit communicating with and extending from the enlarged through opening zone 18, and extending in a locking direction 20, e.g., parallel to the rotation axis 6.
At least one, preferably two or more groups 21 of said blade mounting seats 14 are formed to fix each individual dragging blade 13 to the side wall 8, where the individual blade mounting seats 14 of each group 21 are arranged in sequence in the locking direction 20.

Description of the coupling members 15

The coupling members 15 are made of a plastic material, e.g., formed in one piece together with the dragging blade 13, and can be tooth- or mushroom-shaped with a stem 22 and an enlarged coupling head 23 with respect to the stem 22 and forming an anti-extraction step 23'.
The coupling members 15 can be inserted, from the inner space 11 of the drum 7, into the blade mounting seats 14 so that the coupling head 23 radially comes out of the side wall 8 and the anti-extraction step 23' abuts from the outside against an edge 17 of the blade mounting seat 14, locking the dragging blade 13 in place.
According to an embodiment, the coupling members 15 can be:

inserted, from the inner space 11 of the drum 7, into the enlarged through opening zone 18 of the blade mounting seats 14, allowing a free passage of the coupling heads 23, and
then, the already inserted coupling members 15 with the coupling head 23 radially protruding outside the side wall 8 are transversely moved in the locking direction 20 so that the stem 22 enters the narrowed through opening zone 19 and the anti-extraction step 23' abuts from the outside against the edge 17 of the blade mounting seat 14 at the narrowed through opening zone 19.

Description of the protective protuberances 16

According to an embodiment, the protective protuberances 16 comprise metal sheet bosses protruding from the side wall 8 towards the outside of the drum 7, for example in a substantially radial direction with respect to the rotation axis 6.
According to an embodiment, one said protective protuberance 16 is arranged at each blade mounting seat 14, respectively, at a protection distance 24 measured in a circumferential direction 25 of the side wall 8 with respect to the rotation axis 6, less than four times the extension of the blade mounting seat 14 in said circumferential direction 25, preferably less than three times the extension of the blade mounting seat 14 in said circumferential direction 25.
Advantageously, the protection distance 24 is less than four times the extension of the narrowed through opening zone 19 of the blade mounting seat 14 in said circumferential direction 25, preferably less than three times the extension of the narrowed through opening zone 19 of the blade mounting seat 14 in said circumferential direction 25.
According to an embodiment, the protective protuberance(s) 16, associated with a blade mounting seats 14, respectively, is/are positioned on only one side of the blade mounting seat 14, which forms a main rotation side (and direction) (or spinning rotation) of the drum 7 or of the side wall 8 of the drum 7.
According to an embodiment, the protective protuberance(s) 16 associated with a blade mounting seat 14, respectively, is/are positioned on both sides of the blade mounting seat 14, which form two opposite sides (and directions) of rotation of the drum 7 or of the side wall 8 of the drum 7.
According to an embodiment, the protective protuberance(s) 16, associated with a blade mounting seat 14, respectively, is/are positioned at the narrowed through opening zone 19 or only at the narrowed through opening zone 19 of the respective blade mounting seat 14.
According to an embodiment, the protective protuberances 16 have a radial height 26 with respect to a plane defined by an edge 17 of the blade mounting seat 14, the radial height 26 being greater than 2/3 of a radial extension 27 of the coupling member 15 outside the blade mounting seat 14 when the coupling member 15 is completely coupled to the blade mounting seat 14.
Preferably, the radial height 26 is greater than the radial extension 27 with the coupling member 15 fully coupled to the blade mounting seat 14.
Those skilled in the art will appreciate how the invention overcomes the drawback of the prior art and simply and reliably protects the dragging blades 13 from damage.

Reference numerals in the description and drawings

washing machine 1
housing 2
tank 3
tank opening 4
door 5
rotation axis 6
drum 7
side wall 8
rear wall 9
front wall 10
inner space 11 of the drum
drum opening 12
dragging blades 13
blade mounting seats 14
coupling members 15
protective protuberances 16
edge 17 of the blade mounting seat
enlarged through opening zone 18
narrowed through opening zone 19
locking direction 20
groups 21 of blade mounting seats
stem 22
coupling head 23
anti-extraction step 23'
protection distance 24
circumferential direction 25
radial height 26 of the protuberance
radial extension 27 of the coupling member

Claims

A laundry drum (7) for a washing machine (1) or washer dryer or tumble-dryer, comprising:
- a rear wall (9),

- a front wall (10) opposite to the rear wall (9),

- a side wall (8) extending about a rotation axis (6) of at least the side wall (8) of the drum (7), and which is connected to or borders with the rear (9) and front (10) walls to delimit an inner space (11) of the drum (7) for containing laundry,

- a plurality of blade mounting seats (14) formed in the side wall (8) in the form of through apertures to accommodate corresponding coupling members (15) of one or more dragging blades (13) mountable in the drum (7),
characterized by comprising a plurality of protective protuberances (16) protruding outwards from the side wall (8) and positioned beside each of said blade mounting seats (14), respectively, in a circumferential rotation direction (25) of the side wall (8).
A laundry drum (7) according to claim 1, wherein each of the blade mounting seats (14) is delimited by an edge (17) of cut metal sheet or injection molded plastic wall, which delimits an enlarged through opening zone (18) and an adjacent and communicating narrowed through opening zone (19) of reduced width with respect to the enlarged through opening zone (18).
A laundry drum (7) according to claim 2, wherein the enlarged through opening zone (18) is substantially rectangular and the narrowed through opening zone (19) is a linear slit extending from the enlarged through opening zone (18) in a locking direction (20) parallel to the rotation axis (6).
A laundry drum (7) according to claim 3, wherein at least one or two groups (21) of said blade mounting seats (14) are formed to fix each individual dragging blade (13) to the side wall (8), wherein the individual blade mounting seats (14) of each group (21) are arranged in sequence in the locking direction (20).
A laundry drum (7) according to any one of the preceding claims, wherein the protective protuberances (16) comprise metal sheet bosses protruding from the side wall (8) towards the outside of the drum (7) in a substantially radial direction with respect to the rotation axis (6), and/or
the protective protuberance(s) (16), associated with one of said blade mounting seats (14), respectively, is/are positioned on both sides of the blade mounting seat (14), which form two opposite sides and directions of rotation of the side wall (8) of the drum (7).
A laundry drum (7) according to any one of the preceding claims, wherein one said protective protuberance (16) is arranged at each blade mounting seat (14), respectively, at a protection distance (24) from the blade mounting seat (14), measured in a circumferential direction (25) of the side wall (8) with respect to the rotation axis (6), less than four times the extension of the blade mounting seat (14) in said circumferential direction (25) or less than three times the extension of the blade mounting seat (14) in said circumferential direction (25).
A laundry drum (7) according to claims 2 and 5, wherein the protection distance (24) is less than four times the extension of the narrowed through opening zone (19) of the blade mounting seat (14) in said circumferential direction (25), or less than three times the extension of the narrowed through opening zone (19) of the blade mounting seat (14) in said circumferential direction (25).
A laundry drum (7) according to any one of the preceding claims, wherein the protective protuberance(s) (16), associated with one of said blade mounting seats (14), respectively, is/are positioned on only one side of the blade mounting seat (14), which forms a main side and direction of rotation of the side wall (8) of the drum (7).
A laundry drum (7) according to any one of claims 2 to 8, wherein the protective protuberance(s) (16), associated with one of said blade mounting seats (14), respectively, is/are positioned at the narrowed through opening zone (19) of the respective blade mounting seat (14).
A laundry drum (7) according to any one of the preceding claims, comprising said one or more dragging blades (13) mounted in the drum (7).
A laundry drum (7) according to claim 10, wherein the coupling members (15) are made of a plastic material, formed in one piece together with the dragging blade (13), and are tooth- or mushroom-shaped with a stem (22) and an enlarged coupling head (23) with respect to the stem (22) and forming an anti-extraction step (23').
A laundry drum (7) according to claim 11 and claim 2, wherein the coupling members (15) are insertable, from the inner space (11), into the blade mounting seats (14) so that the coupling head (23) radially comes out of the side wall (8) and the anti-extraction step (23') abuts from the outside against an edge (17) of the blade mounting seat (14), locking the dragging blade (13) in place.
A laundry drum (7) according to claim 11, wherein the coupling members (15) are:
- insertable, from the inner space (11), into the enlarged through opening zone (18) of the blade mounting seats (14), allowing a free passage of the coupling heads (23), and

- then, the already inserted coupling members (15) with the coupling head (23) radially protruding outside the side wall (8) are transversely movable in a locking direction (20) so that the stem (22) enters the narrowed through opening zone (19) and the anti-extraction step abuts from the outside against the edge (17) of the blade mounting seat (14) at the narrowed through opening zone (19).
A laundry drum (7) according to any one of claims 10 to 13, wherein the protective protuberances (16) have a radial height (26) with respect to a plane defined by an edge (17) of the blade mounting seat (14), said radial height (26) being greater than 2/3 of a radial extension (27) of the coupling member (15) outside the blade mounting seat (14) when the coupling member (15) is completely coupled to the blade mounting seat (14).
A laundry drum (7) according to claim 14, wherein the radial height (26) is greater than the radial extension (27).