Technical Field
[0001] This invention is related to the drums that are used in the washing machines and
tumble dryers.
Description of the Prior Art
[0002] As well known, there are drums inside such white goods as washing machines and tumble
dryers used so as to clean the laundry and dry them. Mounted inside such machines,
the drums are units with a perforated structure which can spin at a pre - determined
speed. These perforations are designed with a view to enabling the water to reach
the laundry in the drum of the washing machine and discharging water in the drum during
the process of wringing out. And in the drums of the tumble dryers, similarly these
perforated structure functions to move the evaporating water off the laundry. However,
during the spinning of the drums, if the mentioned perforations have sharp edges in
particular, they wear out the laundry. Therefore drum units which functions without
wearing out the laundry are required.
[0003] There are several solutions available which are included in the existing technical
know - how for the laundry to be dried. For example, in the patent publication with
the number
W02009090107, a drum with "V" shaped channels is disclosed. The perforations on this drum are
opened in such a way as to be placed on the same flanges of the channels. The drum
also designed to spin only in one direction and this reduces the extent the laundry
touch the perforations during the spinning process. Though, it is possible for the
soft texture laundry in particular to rub against these perforations on a drum having
such a structure. The geometrical forms of the perforations disclosed in the aforementioned
application do not have the capacity to protect the laundry against wearing out.
Short Description of the Invention
[0004] The perforated drum of present invention has been developed for the washing machines
and / or tumbles dryers and contains perforations having special geometrical forms
to prevent the laundry from wearing out. Accordingly, each drum perforation has been
produced extending toward the outer surface of the drum; their internal and external
flanges moved off the center of the perforation; and the internal surface of the perforations
are designed in such a way as not to form a sharp line and its cross-section to have
a curved surface. Thus, the wearing out of the laundry during the washing and drying
processes is avoided. Moreover, even the existence of burrs left around the perforations
during the production is considered as a factor that does not affect the laundry.
Additionally, this eliminates the need to perform the burr removing process during
the production of the drum and reduces the production costs of the drum.
Aim of the Invention
[0005] The aim of this invention is to ensure that the perforations in the drums used in
the washing machines and/or tumble dryers do not harm the laundry.
[0006] Another aim of the invention is to produce drum perforations in such a form as to
prevent the laundry from wearing out.
[0007] A further aim of this invention is to provide a safe drum the manufacture of which
is easy and cost-effective.
Description of Figures
[0008] The examples of the drums and the perforations of the present invention have been
illustrated in the annexed figures wherein;
- Figure 1
- is the perspective view of the internal structure of a washing machine.
- Figure 2
- is the perspective view of a drum.
- Figure 3
- is the sectional view of a sample drum perforation of the known art.
- Figure 4
- is the sectional view of the present invention of drum perforation.
- Figure 5
- is the sectional view of another said invention of drum perforation.
- Figure 6
- is the sectional view of another said invention of drum perforation.
[0009] The units in displayed in the figures are assigned individual numbers and what these
numbers stand for is provided below.
White goods (1)
Tub (2)
Drum (3)
Drum perforation (4)
Drum perforation (4') (of the known art)
Internal surface (5)
Internal surface (5') (of the known art)
Outer surface (6)
Outer surface (6') (of the known art)
Internal Edge (7)
Internal Edge (7') (of the known art)
Outer edge (8)
Outer edge (8') (of the known art)
Perforation internal surface (9)
Curved cross-sectional surface (10)
Tilted cross-sectional surface (11)
Flat cross-sectional surface (12)
Perforation center (C)
Back wall (D)
Disclosure of the Invention
[0010] The perspective view of a sample white goods (1) is given in the Figure 1. Here the
white goods (1) is given as a washing machine but the invention can be applied to
both the drying machines and also the machines that can wash and dry the laundry.
As it is known, the laundry and drying machines include a tub (2) containing a rotatable
drum (3) with perforations. Drums (3) are generally manufactured by circularly forming
the flat sheet materials after perforation. A laundry loading opening is placed at
the frontal side of the drums (3). Perforation may be applied to the back wall of
the drum (3) which is in flat form. In Figure 2, a drum (3) with perforations (4,
4') is shown. While, the perforations (4, 4') here are shown on the curved surface
of the drum (3), they can also be placed on the back wall (D) of the drum (3).
[0011] Cross sectional views from different geometrical shapes of a drum perforation (4,
4') are given in the Figure 3-6. In Figure 3, a cross sectional geometry of a drum
perforation (4') of the prior art is shown. The edge (7') of this drum perforation
(4') at the internal surface of the drum (5') (the surface contacting with the laundry)
and the edge (8') at the external surface (6') are sharp. Since the internal and external
edges (7', 8') of drum perforation (4') in such a geometrical structure contact with
the laundry thus damaging the clothes, new drum perforation (4) with different geometrical
structures have been developed as shown on the Figure 4-6.
[0012] The common points of drum perforations (4) of this invention, as shown in the Figure
4-6, are that the perforation (4) is extended towards the external surface of the
drum (6), that the internal and external edges (7, 8) are alienated away from the
perforation center (C) and that the internal edge (9) of the perforation is formed
by avoiding any sharp lines, in a way that the cross section of the internal edge
has a curved surface (10). Additionally, the section, where the internal surface of
the perforation (9) and the internal surface of the drum (5) are connected, is rounded.
[0013] In the sample drum perforation (4) given in the Figure 4, there is a surface (11)
the cross section of which is inclined between the internal surface of the drum (5)
and the curved surface(10).
[0014] The sample drum perforation shown in the Figure 5, on the other hand, is similar
to the perforation at the Figure 4; the difference here is that there is a surface
(12) in the drum perforation (4), the cross section of which is flat and which divides
the curved surface (10) into two.
[0015] In Figure 6, on the other hand; a drum perforation (4), the internal surface (9)
of which is formed as a completely curved surface cross section (10) is shown.
[0016] The wearing out of the clothes during the washing and drying processes is prevented
by the fact that the internal and external edges (7, 8) of drum perforations (4) shown
in the Figure 4-6, are curved outwardly from the perforation center (C) to avoid contact
with the clothes, along with the fact that the internal surface of the perforation
(9) is curved and that the perforation is extended to the external surface (6) of
the drum. Additionally, even if burrs, remaining from the manufacturing process, are
present at perforation edges (7, 8) they will be considered as an element not having
any effect on clothes. Besides, this also eliminates the necessity of burr removal
process during the manufacture of the drum (3) which decreases the manufacture cost
of the drum (3).
1. A perforated drum (3) for the washing machines and tumble dryers characterized in that each drum perforation (4) have been produced extending toward the outer surface of
the drum (6); their internal and external edges (7, 8) moved off the center of the
perforation (C); and the internal surface of the perforations (9) designed in such
a way as not to form a sharp line and its cross - section to have a curved surface
(10).
2. A perforated drum (3) according to Claim 1 characterized in that inside the perforation drum (4) is a tilted cross-sectional surface (11) between
the internal surface of the drum (5) and the mentioned curved surface (10).
3. A perforated drum (3) according to Claim 1 or Claim 2 and characterized in that there is a flat cross-sectional surface (12) in the drum perforations (4) which divides
the curved surface (10) into two.
4. A perforated drum (3) according to any of the aforementioned claims and characterized in that the section where the internal surface of perforation (9) and internal surface of
the drum (5) are connected is rounded.