[0001] The present invention relates to a detergent supply unit for a laundry washing machine
for the supply of particulate and/or liquid detergents and of additives to the washing
tub of the machine.
[0002] At present all laundry washing machines are provided with a detergent supply unit
disposed in an upper portion of the machine and formed with a number of separate compartments
for containing additives and detergent in particulate and/ /or liquid form, said compartments
being connected to a conduit leading to the washing tub.
[0003] The detergent supply unit is provided with per se known control devices adapted to
intercept the water fed to the supply unit and to selectively divert it to individual
compartments for removing therefrom the detergent or additive contained therein and
transferring it to the washing tub.
[0004] For achieving this effect, the introduction of the water into the actually employed
detergent supply units is carried out in two different modes.
[0005] According to a first mode, the water is separately supplied to each compartment of
the supply unit so as to impinge on the bottom and/or on a part of the interior wall
surface of the respective compartment. This system makes use of the dynamic pressure
of the water for removing the detergents from the compartments within a sufficiently
short time, but is incapable of ensuring a thorough cleaning of the supply unit, so
that the individual compartments have to be periodically cleaned.
[0006] According to the second mode, the water is supplied to a distributor disposed above
the compartments of the supply unit and provided with a number of separate internal
passages communicating with individual compartments through nozzles or the like.
[0007] According to this system, the water is thus suppied in the form of a number of jets
impinging on substantially the entire interior wall surface of the respective compartments
so as to ensure thorough cleaning thereof. As on the other hand the cinetic energy
of the water is dispersed over a relatively large area, emptying the various compartments
of their contents takes a considerably long time.
[0008] In addition, both of the described systems are only suitable in the case of compartments
having a large cross-sectional area and a limited height, and are thus badly suited
for employ in laundry washing machines of the top-loading type or of compact construction.
[0009] It is an object of the present invention to eliminate the above noted shortcomings
by providing a detergent supply unit permitting the detergents and additives contained
therein to be rapidly and completely transferred to the washing tub of the laundry
washing machine, so as to ensure optimum utilization of these substances.
[0010] For attaining this object, the invention makes use of the principle of contemporaneously
introducing the water into the supply unit in two directions, so that a first portion
of the water impinges on the bottom with considerably dynamic energy so as to promote
the discharge of the detergent or additive from the compartment, while another portion
of the water sweeps the interior wall surface of the respective compartment so as
to ensure its being thoroughly cleaned.
[0011] The supply unit according to the invention is additionally provided with a conduit
for diverting part of the water supplied thereto so as to achieve recirculation thereof
under pressure for permitting any detergent accumulated in the discharge portion of
the machine to be efficiently recuperated.
[0012] These and other objects are attained according to the invention in a laundry washing
machine comprising a detergent supply unit provided with respective inlets for the
supply thereto of cold and hot water from the water mains and connected to a washing
tub the lower portion of which communicates with a discharge unit, said detergent
supply unit comprising a container divided into a number of separate compartments
adapted to contain detergetns and additives, and a disstributor adapted to be removably
mounted on said container and provided with separate internal passages communicating
with the various compartments, a control piston being adapted to be actuated by the
program unit of the machine for selectively diverting the water to each of said internal
passages.
[0013] According to the invention, a detergent supply unit of the type defined above is
characterized in that at least one of said compartments is provided with conduit means
adapted to introduce the water also adjacetn the bottom of said compartment, collector
means being connected to said discharge unit for causing a part of the supplied water
to recirculate therethrough.
[0014] The invention will be more clearly understood from the following description of an
exemplary embodiment with refer- ance to the accompanying drawings, wherein:
fig. 1 shows a diagrammatic perspective view of a laundry washing machine including
a detergent supply unit according to the invention,
fig. 2 shows a partially sectioned exploded perspective view of the supply unit according
to the invention,
fig. 3 shows a partially sectioned perspective view of the supply unit of fig. 2 on
a larger scale,
fig. 4 shows a detail of the supply unit of fig. 3 sectioned along the line A-A,
fig. 5 shows a further detail of the supply unit sectioned along the line B-B in fig.
3, and
fig. 6 shows the detail of fig. 5 sectioned along the line C-C.
[0015] With reference to fig. 1, a laundry washing machine of the top loading type comprises,
for the purpose of the present invention, a housing 6 surrounding a washing tub 7
the lower portion of which is connected to a bellows-type conduit 8 leading to a filter
unit 9 itself connected to a discharge pump 10 and a discharge conduit 11 leading
therefrom.
[0016] Mounted in the upper portion of housing 6 is a detergent supply unit 12 provided
with a closure lid 13 hingedly mounted on the upper plane of housing 6. Supply unit
12 is connected respectively to a cold water supply mains through a conduit 14 including
a solenoid valve 15, to a hot water supply source through a conduit 16 including a
solenoid valve 17, and to filter unit 9 through a conduit 18.
[0017] Supply unit 12 further communicates with a transfer conduit 19 connecting it to washing
tub 7.
[0018] With referecne to fig. 2, detergent supply unit 12 basically consists of three main
components: a container 20, a distributor 21, and a piston 22. Container 20 is integrally
foremd of a synthetic resin or the like and comprises compartments 23 and 24 for the
detergents for a first and a second washing phase, and compartments 25 and 26 for
additives, generally in liquid form. Formed on the interior wall surface of each compartment
23 and 24, according to a specific characteristic of the invention, are water conduit
means 27 comprising a wall member 28 vertically slidable between guides 29, as particularly
shown in fig. 3.
[0019] Compartments 25 and 26 on the other hand each contain a siphon 30 and 31, respectively,
for discharging the liquid additives into tub 7.
[0020] Container 20 is additionally formed with tubular projections 32, 33, and 34 for connection
to conduits 16, 18 and 19, respectively (fig. 1).
[0021] Container 20 has a further opening 35 through which the interior of tubular connector
projection 34 communicates with the surrounding environment.
[0022] Container 20 is finally formed with a lateral guide 36 for slidably receiving piston
22 therein. The latter is provided with a first conduit 37 for diverting the cold
water to the compartments of container 20, and a second conduit 38 located adjacent
first conduit 37 and serving to divert the hot water in an analogous manner.
[0023] Piston 22 further comprises a rod 39 having a bifurcate end portion 40 for connection
to (not shown) control elements operable to displace piston 22.
[0024] Distributor 21 is formed with three openings 41, 42 and 43 corresponding respectively
to compartments 23, 24 and 25,26 when distributor is mounted on container 20 and releasably
secured thereto by means of hook members 44 engaging apertured projections 45.
[0025] Distributor 21 is further provided with a nozzle 46 connected to conduit 14 for the
supply of cold water (fig.1). Nozzle 46 is coaxially aligned with conduit 37 of piston
22 in the operative position thereof.
[0026] The system of the selective water supply to distributor 21 by means of displaceable
piston 22 corresponds to that described in Italian Patent 1,045,343 in the name of
the present applicant.
[0027] With reference also to fig. 3, it is noted that between the inlet opening of conduit
37 and nozzle 46 there always remains a free space (air break) to be crossed by the
jet of the water supply as required by safety regulations.
[0028] Cold water is supplied to any of compartments 23 to 26 by displacing piston 22 into
alignment with the openings of corresponding passages formed in distributor 21 and
indicated by phantom lines in fig. 3. Hot water on the other hand can only be supplied
to main washing phase detergent compartment 23 after moving piston 22 to a position
in which conduit 38 is aligned with tubular connector projection 32.
[0029] The passages of distributor 21 associated with compartments 25 and 26 open directly
into the latter. The passages associated with compartments 23 and 24 feed the water
to a collector 47 extending around the upper edge of the corresponding opening 41
and 42, respectively, of distributor 21. Collector 47 associated with compartment
23 is visible in fig. 3.
[0030] From the respective collector 47, water enters the respective compartment through
a number of peripherally located nozzles 48 and through the already mentiones conduit
means 27 communicating with a passaeg 49 integrally formed within distributor 21.
[0031] By means of a partition 50, the interior of conduit means 27 is formed to the shape
of a venturi nozzle effective to impart a higher energy to the water jet. Conduit
means 27 opens proximate the bottom of the respective compartment 23 or 24 so as to
ensure the complete removal therefrom of the detergent, in cooperation with the water
jets issuing from nozzles 48 and impinging on the interior wall surface of the respective
compartments. Tubular connector projection 33 connected to filter unit 9 vie conduit
18 (fig.1) is located below and in communication with nozzle 46 so as to divert part
of the cold water supply for creating a circulation of this water through filter unit
9 and bellows conduit 8 to tub 7. In this manner, any detergent deposited in filter
unit 9 and/or bellows conduit 8 is effectively recuperated so as not to be discharged
without having been utilized. The wall of tubular connector projection 33 is formed
with a vertical slot 51 and a passage 52 located therebelow, slot 51 and passage 52
communicating with a chamber 53 formed below guide 36 and itself communicating with
conduit 34. The dimensions of slot 51 are selected so as to permit the pressure of
the water within conduit 18 to be kept between predetermined limits, while passage
52 permits any air bubbles entrained by the water to escape from conduit 18. Chamber
53 in addition serves for collecting any water leakage from the air break between
nozzle 46 and piston 22 as well as part of the hot water supply via a passage 66 associated
with tubular connector projection 32. With reference to fig. 4, compartment 25, similar
to compartment 26, is in free communication with tubular connector projection 34 leading
towards tub 7 and formed with opening 35 defined by an interior wall 54. Shown in
fig. 4 is an arrangement for securing a splash cover 67 on top of the detergent supply
unit. This is accomplished by means of resilient clamps 55 engaging seats 56 and 57
formed on splash cover 67 and container 20, respectively. In this manner, the detergent
supply unit is readily accessible without requiring the entire splash cover or the
top cover of the machine to be dismounted. With reference to figs 5 and 6 there is
shown a preferred embodiment of means permitting the employ of liquid detergents in
the pre-laundering and main laundering compartments without modifying the structural
and functional characteristics of the supply unit according to the invention. Considering
for instance the compartment 23 for the main laundering detergent, there is provided
a cup-shaped element 58 to be inserted therein and having an enlarged upper rim 59
adapted to rest on the edge of distributor 21. Integrally formed with cup-shaped element
58 is a vertical tube 60, while its bottom is provided with openings for receiving
therein respective valve poppets 61 biased towards their closure positions by a spring
62. An inverted cup-shaped element 63 is inserted over vertical tube 60, with its
lower edge resting on valve poppets 61.
[0032] The described arrangement forsm a sifon for the transfer of liquid detergents to
the washing tub as water is supplied to cup-shaped element 58 via passage 47 of distrib
utor 21 and a further passage 64 formed opposite an opening 65 in the wall of cup-shaped
element 58.
[0033] For discharging any liquid detergent remaining within cup-shaped element 58 below
the level of inverted cup-shaped element 63, valve poppets 61 may be opened by simply
depressing inverted cup-shaped element 63 against the action of spring 62.
[0034] This simple operation should always be carried out before supplying the liquid detergent
preparatory to a subsequent washing cycle.
[0035] In summary, the detergent and additive supply unit for laundry washing machines according
to the invention is of simple and compact construction and highly efficient in use,
ensuring an improved and faster supply of detergents and additives to the tub of the
machine as well as the complete discharge thereof from the respective compartments
so as to avoid any incrustation and sedimentation forming therein.
[0036] In addition, the described supply unit is highly versatile in use as it may be employed
in washing machines of the top-loading as well as of the front-loading type and even
permits the employ of liquid detergents by the provision of accessories adapted to
be installed in a simple manner.
1. A detergent supply unit for a laundry washing machine provided with connections
for the supply respectively of cold mains water and hot water and including a washing
tub the lower portion of which communicates with a discharge assembly, said supply
unit being provided with a container divided into a number of separate compartments
for containing detergetns and additives, and with a distributor removably secured
to said container and formed with separate internal passages communicating with respective
ones of said compartments, a control piston being adapted to be actuated by the program
unit of the machine for selectively divert the supplied water to each of said internal
passages, characterized in that at least one of said compartments (23 - 26) is provided
with conduit means (27) adapted to introduce at least part of the water adjacent the
bottom of the respective compartment, collector means (33, 36, 53) of said supply
unit being connected to said discharge assembly (8, 9) for causing part of the supplied
water to be recirculated therethrough.
2. A detergent supply unit according to claim 1, characterized in that said conduit
means (27) comprises a wall member (28) retained for vertical sliding movement between
guides (29) formed on the interior wall surface of the respective compartment (23,
24), and is in communication with a passage (49) of said distributor (21).
3. A detergent supply unit according to claim 2, characterized in that said conduit
means (27) is internally provided with baffle means (50) for forming a venturi passage
therein.
4. A detergent supply unit according to claim 1, characterized in that said collector
means include a lateral guide (36) in which said piston (22) is slidably guided, and
a chamber (53) located therebelow in communication with a tubular connector portion
(33), said tubular connector portion (33) communicating with a nozzle (46) for the
supply of water to the supply unit.
5. A detergent supply unit according to claim 4, characterized in that said tubular
connector portion (33) is formed with a vertical slot (51) and a passage (52) both
in communication with said. chamber (53), said chamber (53) itself being open towards
a tubular connector portion (34) connected to said washing tub (7).
6. A detergent supply unit according to claim 1, characterized in that said container
(20) is formed with an opening (35) communicating with the environment and internally
delimited by a wall (54).
7. A detergent supply unit according to claim 1, characterized in that there is provided
a liquid detergent container (58) adapted to be removably inserted into at least one
of said compartments (23, 24) and provided with siphon means (60-63) and at least
one opening (65) opposite a passage (64) formed in said distributor (21).
8. A detergent supply unit according to claim 7, characterized in that said siphon
means comprise a vertical tube (60) located internally of said container (58) and
communicating with the respective compartment, and a cup-shaped element (63) removably
slipped over said vertical tube (60) and adapted to cooperate with valve poppets (61)
inserted into respective openings in the bottom of said container (58) and biased
to their closed positions by resilient means (62).
9. A laundry washing machine according to any of the preceding claims, substantially
as described with reference to the accompanying drawings and for the stated purposes.