[0001] The present invention relates to a washing machine having a detergent dispensing
system comprising a drawer with detergent chambers and moveable within a stationary
housing and further having a piping system for hydraulically linking the housing with
a tub of the washing machine.
[0002] Such detergent dispensing systems are well known in the art of the washing machines,
and they are widely used either in front loading or top loading washing machines.
In the following with the term "detergent" we mean every kind of solid or liquid detergent
and washing aid like softeners, bleaching agents etc.
[0003] One of the problem of washing machines is a proper ventilation of the tub when it
is filled with water or during the washing and rinsing stages of the laundry washing
process. Known washing machines are provided with dedicated ventilation hoses which
connect the tub with the outside environment; this increases the complexity of the
overall construction of the appliance. Other washing machines rely on the ventilation
from the housing of the detergent drawer. If this may be considered acceptable for
big drawers where there is a considerable space for loading detergents, it is not
the case where a big amount of detergent has to be loaded in a relatively small detergent
drawer. In this case a possible water overflow from the tub may flood the housing
of the detergent drawer and create leakage on the front panel of the washing machine.
[0004] It is therefore an object of the present invention to provide a washing machine which
does not present the above drawbacks and which is simple to be manufactured.
[0005] According to the invention, the above object is reached thanks to the technical features
listed in the appended claims.
[0006] According to the invention, the housing of the detergent drawer presents a side opening
which prevents a possible water overflow from the tub to reach the upper level of
the housing, by allowing such overflow to be discharged inside the body of the washing
machine and therefore reducing problems to the user in case of technical malfunction.
As a matter of fact any overflow internal to the body of the washer is usually collected
within a bottom plate of the washing machine, where is usually mounted a device for
detecting water leakage within the washing machine. If the above overflow is of a
certain amount, the detecting system will inform the user that something is wrong
in the function of the machine, therefore avoiding further water overflow.
[0007] According to another technical feature of the invention, the detergent chambers of
the detergent drawer are provided with a front upper rim which is inclined and which
is provided with one or more openings which act as an indicator for maximum fill level
of detergent. This is also designed for preventing a possible water overflow deriving
from the obstruction of the water passage in the drawer caused by consolidated detergent
powder blocks which, without the above openings, could flood the drawer and cause
leakage on the front panel of the washing machine.
[0008] According to another technical feature of the invention, the front wall of the washing
machine is provided with a movable flap for accessing the detergent drawer, such flap
being made of acoustically insulating material. Thanks to this further feature the
overall noise of the working washing machine as perceived by the user is reduced.
[0009] Further advantages and features according to the present invention will become clear
from the detailed description, provided as a non limiting example, with reference
to the attached drawings in which:
- Figure 1 is a side section view of a portion of a washing machine according to the
invention;
- Figure 2 is a front view of a component shown in figure 1;
- Figure 3 is a perspective and partially sectioned view of a detergent dispensing system
used in the washing machine of figure 1;
- Figure 4 is a perspective partially sectioned view of the detergent drawer used in
the detergent dispensing system of figure 3,
- Figure 5 is a top view of the detergent drawer of figure 4; and
- Figures 6A and 6B are side sectioned views of the detergent drawer of figures 4 and
5 in a normal working condition and in an overflow condition respectively.
[0010] With reference to the drawings, a horizontal axis washing machine comprises a cabinet
10 in which a tub 12 is elastically suspended. On a front face 10a of the cabinet,
the washing machine presents a front opening 14 which is closed by a wall 16a which
is fastened to or integral with a detergent drawer 16 which is slidably mounted in
a fixed housing 18. The wall 16a is, in its closed configuration shown in figure 1,
substantially flush with the adjacent front and upper face of the cabinet 10 and it
is provided with a rotating flap 20 which is maintained in its vertical position by
a spring (not shown). The flap 20 can be moved by the user's finger when he/she has
to open the detergent drawer 16. The rotating flap 20 is preferably made of acoustical
insulating material, as well as the wall 16a of the drawer 16 in order to minimize
the noise that can be generated by the machine during its working.
[0011] The housing 18 presents a box-like shape and have a front wall with an upper opening
18a which allows passage of the drawer 16. Below the opening 18a, the housing 18 presents
an overflow opening 18b whose function will be clear in the following description.
A bottom wall 18c of the housing 18 has portions inclined towards a collector 22 which
is connected to a rubber pipe 24 connected to the tub 12 for delivery water and detergent
to the tub itself. The water is fed by a spray system 26 placed, in a known way, at
the top of the housing 18 and connected to a water delivery system by means of pipe
fittings 27 (figure 3).
[0012] When during the washing cycle of the washing machine, for whatever reason, water
reaches a level indicated with reference L in figure 1, it spills out from the overflow
opening 18b without any spillage on the front wall 10a of the cabinet 10. Such accidental
spillage is collected on the bottom plate (not shown) provided at the bottom of the
cabinet 10 (such plate being also used for reducing noise emission from the machine).
[0013] With reference to figure 3, with arrows W it is indicated how water is delivered
from the spray system 26 to the tub 12, and with arrows A how the air coming out from
the tub 12 (during filling operation thereof) is vented out from the housing 18. This
system, without any additional hoses for air venting, allows storage of a big amount
of detergents or rinsing/ bleaching additives in a quite reduced space, allowing internal
water overflow and air ventilation during water filling without an ad-hoc exhaust
hose.
[0014] In figures 4 and 5 some details of the detergent drawer 16 are shown (where the front
wall 16a has been removed therefrom for sake of clarity), where compartments B and
C are for powder detergent and compartment D for liquid detergent or rinse aid. The
detergent drawer 16 is composed by a base tank portion 30 on which an upper auxiliary
tank portion 32 is removably mounted. By removing the auxiliary tank portion 32 the
compartment B can be easily cleaned by the user. Both the base tank portion 30 and
the upper auxiliary tank portion 32 have open rear wall for water passage. In the
compartment D an usual siphon is placed (not shown), which allow the automatic discharge
of water plus detergent when a predetermined water level is reached. As an example
of volumes of detergent, chamber B may store around 300 cm
3 of detergent, while chambers C and D can store around 80 and 150 cm
3 respectively. Dimensions of the drawer 16 can vary in a wide range, and as an example
a length about 180 mm, a height around 40 mm and a width around 90 mm have been used
by the applicant.
[0015] As shown in figures 4 and 6, the auxiliary tank portion 32 presents, on its front
edge, an inclined surface 34 which extends for a certain length into the compartment
B, and which has two openings 36. In figures 6A and 6B it is shown what is the purpose
of such openings 36. In figure 6A is it shown the normal behavior of the detergent
drawer 16 when water is fed through the spray system 26. In the configuration where
such system delivers water to compartment B, water and detergent flow along the bottom
of the drawer and then are collected in the housing 18 and delivered to the tub 12.
[0016] When, as in figure 6B, a lump of solid detergent K stops the normal route of water,
the presence of the openings 36 allows (as shown by arrows in figure 6B) water to
pass around the lump of solid detergent without the risk of being spilled outside
the drawer 16. According to a further feature of the invention, between the housing
18 and the detergent drawer 16 there are interposed plastic clamps fastened to or
integral with an upper cover of the housing 18 in order to reduce wobbling effect
when drawer is opened or closed. Such clamps can be fastened to the spray system 26
on the housing 18.
[0017] Even if the above description was made with reference to an horizontal axis washing
machine, it is clear that the same detergent system can be used in a vertical axis
washing machine , independently on how the washing machine drum is loaded with clothes
(the invention applies to front loaders and to top loaders as well).
1. Washing machine having a detergent dispensing system comprising a drawer (16) with
detergent chambers (B, C, D) and movable within a housing (18) mounted on the washing
machine and further having a piping system (24) for hydraulically connecting the housing
(18) with a tub (12) of the washing machine, characterized in that the housing (18) presents an opening (18b) for allowing water overflow from the tub
(12).
2. Washing machine according to claim 1, wherein the housing (18) is box-shaped, said
opening (18b) being provided on a front side of said housing (18) below a second opening
(18a) for the passage of the detergent drawer (16).
3. Washing machine according to claim 2, wherein the box-shaped housing (18) presents
a bottom wall (18c) with inclined surfaces, such overflow opening (18b) being provided
adjacent one of such inclined surfaces.
4. Washing machine according to any of the preceding claims, wherein said overflow opening
(18b) is positioned far from a front panel (10a) of the washing machine.
5. Washing machine according to any of the preceding claims, wherein the detergent chambers
(B, C, D) comprise a first front chamber (B) placed in a front zone of the drawer
(16) and having a width corresponding substantially to the entire width of the drawer
(16), at least two rear chambers (C, D) placed in a rear zone of the drawer, such
rear chambers (C, D) having a front upper edge which a rim (34) provided with at least
one water overflow hole (36).
6. Washing machine according to claim 5, wherein the two rear chambers (C, D) are formed
in an auxiliary tank device (32) removably installed in the drawer (16, 30).
7. Washing machine according to claim 5 or 6, wherein a first rear chamber (C) is configured
to dispense powder detergent and a second rear chamber (D) is configured to dispense
liquid detergent or liquid washing/rinsing aid.
8. Washing machine according to any of claims 5-7, wherein the rim (34) is inclined in
order to decrease chances of being obstructed by lump of solid detergent.
9. Washing machine according to any of the preceding claims, wherein the detergent dispensing
system presents a front wall (16a) which is acoustically insulated and is provided
with a movable flap (20) for allowing handling of the drawer (16) and which is maintained
substantially flush with a front surface (10a) of the washing machine.
10. Washing machine according to any of the preceding claims, wherein between the housing
(18) and the drawer (16) there are interposed clamps fastened to or integral with
an upper cover of the housing (18) in order to reduce wobbling effect when drawer
is moved.