GB2276888A

GB2276888A - Washing machine with anti-clogging filter

Info

Publication number: GB2276888A
Application number: GB9320083A
Authority: GB
Inventors: Silvano Cimetta
Original assignee: Zanussi Elettrodomestici SpA
Current assignee: Electrolux Zanussi Elettrodomestici SpA
Priority date: 1993-03-25
Filing date: 1993-09-29
Publication date: 1994-10-12
Anticipated expiration: 2013-09-29
Also published as: ES1026817U; ITPN930008U1; GB2276888B; ITPN930008V0; DE9313174U1; ES1026817Y; FR2703079B1; IT231961Y1; FR2703079A1; GB9320083D0

Abstract

A washing machine, in particular for clothes comprises a washing tub, a conduit 8 which starts from the bottom of the tub and issues into an anti-clogging filter 9 and a discharge pump disposed downstream of the anti-clogging filter. The filter 9 is formed by a first chamber 15 and a second chamber 16. The conduit 8 opens into the filter by way of an upper aperture 17 of the first chamber 15 and said chambers 15, 16 are connected by an upper opening 19. An outlet hole (20) is provided at the upper portion of an external wall of the second chamber. Preferably the anti-clogging filter is a hollow body and the two chambers 15, 16 are separated by a substantially vertical common internal wall 18 up to a height such as to leave said opening 19. The wall 18 may have a slit (23, figure 3) providing further communication between the chambers. The conduit 8 may be shaped in one piece with the filter. <IMAGE>

Description

WASHING MACHINE WITH IMPROVED ANTI-CLOGGING FILTER The invention concerns washing appliances, in particular for domestic use, which are provided with an improved arrangement for discharge of the water from the washing tub.

Washing machines for domestic use are known, in which discharge of the water from the washing tub to the exterior is effected by way of a hydraulic conduit which includes, in this order, a filter, a pump with an associated motor and final conduit section which is extended upwardly to prevent the tub being emptied by way of same, since there are no elements for blocking the water in the conduit. The above-mentioned filter has given rise to numerous different design configurations, and in actual fact, various contrasting opinions have been expressed regarding this function: in accordance with one such opinion the aim of the filter which is disposed immediately upstream of the discharge pump is to intercept any relatively large objects (for example large buttons, hairpins, buckles and clasps, coins etc) which have escaped from the washing drum on to the bottom of the tub and from there into the discharge conduit and which are capable of locking the rotor of the pump if they were to accidentally pass into same.

The filters which are designed to avoid that disadvantage are of an internal labyrinth-type shape with fairly large openings such as to intercept and retain the above-mentioned objects but to allow any other smaller objects to continue on into the pump, trusting that the small size thereof will not cause locking of the pump and that they will be removed together with the liquid without any particular problem.

The filters of that kind afford the advantage of requiring greatly reduced maintenance since it is sufficiently rare for such objects to pass into the discharge conduit.

On the other hand there is the danger here that all the very small objects and in particular any fluff being allowed to pass, will gradually accumulate not against the labyrinth structure but rather against the larger obstacles which go to constitute a second filter with still smaller members, finally blocking it with serious consequences also in regard to the motor for actuating the rotor of the pump.

According to a different opinion the filter upstream of the discharge pump is to filter out as much material as possible in order not to clog the pump. The filters of that kind therefore involve an internal flow path and openings such that only objects of minimum dimensions are allowed to pass while all others are intercepted and stopped; The filters of that type therefore provide very good safeguards in regard to unexpected blockage of the pump, but for that reason they very easily become clogged and accordingly require maintenance for cleaning them much more carefully and systematically.

In addition those filters are normally produced with a suitable component of plastics material which is inserted and locked in the discharge conduit, and that requires the manufacture and fitting of an additional component.

It would therefore be desirable, and this is the aim of the present invention, to provide a clothes washing machine, in particular for domestic use, which is provided with an anti-clogging filter which reduces or eliminates the structural problems and the functional disadvantages described above and which is capable of normally performing the function of carrying water and acting as a filter for protecting the discharge pump at a downstream position, without imposing structural constraints and excessive maintenance burdens.

According to the present invention, there is provided a clothes washing machine comprising a washing tub, a conduit which extends from the bottom of said tub and opens into an anti-clogging filter, and a discharge pump disposed downstream of said anti-clogging filter, wherein said filter is composed of two separate chambers, a first chamber and a second chamber, that the conduit opens into the filter by means of an upper aperture of the first chamber, said chambers being connected by an upper opening and an outlet hole is provided at the upper portion of an external wall of said second chamber.

The invention will be better appreciated from the following description solely by way of non-limiting example with reference to the accompanying drawings in which: Figure 1 is a sectional view of a typical clothes washing machine according to the invention; Figure 2 is a side view in section of a filter according to the invention; and Figure 3 is a front view in section of a filter according to the invention.

With reference to the drawings, shown therein is a mains water feed conduit 1, an internal intake water conduction conduit 2 with an air gap 3, a detergent distributor 4 comprising a plurality of compartments, an electrically operated valve 5 on the intake conduit 2, a washing tub 6, a conduit 8 which carries the washing liquid from the bottom of the tub 6 to the anti-clogging filter 9, a discharge pump 10 downstream of the filter for discharge of the liquid and a final discharge conduit section 11 which carries said liquid to the exterior by means of a suitable siphon which is raised to an appropriate height.

In accordance with the invention the anti-clogging filter 9 is a single hollow body of rounded shape made up of two separate chambers, a first chamber 15 and a second chamber 16.

The first and second chambers 15 and 16 are defined by the external wall of the body of the filter and by an internal common wall 18 which extends almost vertically upwardly from its bottom, to a height such as to leave an opening 19 with respect to the top of the filter, the opening 19 being sufficiently large, as will be described in greater detail hereinafter.

The conduit 8 opens into the filter by means of a wide upper aperture 17 of the first chamber 15. Provided at the upper portion of an external wall of said second chamber is a hole 20 which permits the washing liquid to issue from the filter 9 to the discharge pump 10.

The first chamber is of a fairly accentuated internal volume and the conduit 8 is oriented in the lower region thereof towards the centre of the first chamber 15.

In contrast the second chamber is of a fairly reduced volume and its transverse dimension is appropriately such as just to contain the outlet hole 20.

The mode of operation of the filter 8 is as follows: During discharge the liquid is drawn in from the bottom of the tub and introduced by means of the conduit 8 into the first chamber 15 from above. On passing into same, any heavy objects which may be entrained by the liquid are projected on to the bottom of that chamber and as fresh liquid exerts pressure to pass into that chamber, the liquid is drawn in to the second chamber 16 by passing though the upper opening 19; it is found that the mixing action combined with the action of passing from the first chamber to the second chamber produces such an effect on the washing liquid and on any foreign bodies contained therein that they are normally deposited on the bottom 21 of the first chamber 16, and remain there under the effect of gravity and also because that zone involves a low level of turbulence and therefore there are not sufficient forces to put the bodies back into the flow.

The foregoing refers in particular to relatively heavy and bulky bodies, which are fairly rarely found in the discharge liquid.

Those bodies are therefore retained on the bottom of the first chamber for very long periods of time, even for the entire life of the machine since, not being affected by the discharge flow, they do not give rise to any problem at least until the possible accumulation thereof reaches a level such as to obstruct either the intake aperture 17 to the first chamber or the opening 19 between the two chambers, and that is extremely unlikely.

All other bodies of small dimensions and in particular fluff are carried away with the flow and there is no danger that they become entangled with the bulkier bodies on the bottom of the chamber 15 since, as explained above, that zone is not directly affected by the flow.

An advantageous feature of the invention comprises the provision in the lower region of an external wall of the first chamber 15 of a suitable hole 22 which can be closed by means of suitable cover as shown in Figure 2. That will make it possible to gain easy access to the interior of that chamber to remove therefrom any objects which are deposited therein, without having to dismantle the entire filter.

A second improvement involves the provision in the above-mentioned vertical wall 18 of a vertical slit or opening 23, preferably over the entire height thereof, and at a position corresponding to a lateral edge of the vertical wall, in such a manner as to remove the seam joining the vertical wall to the external wall of the filter; that is found to be effective to permit a better discharge flow of the liquid from the first chamber to the second chamber, without compromising either the capacity for interception of the bulkier bodies or the lack of influence of the latter of the free passage of the small bodies which are intended to be removed by the downstream pump.

A further improvement involves making the filter by shaping it -in one piece with the conduit 8 from the bottom of the tub; that gives the benefit of simplifying assembly of the invention reducing the costs thereof without the slightest reduction in performance, particularly if the assembly is produced with conventional elastomeric material with which flexible hydraulic conduits are produced.

It will be appreciated that the arrangement described may adopt the most appropriate shape in accordance with the constraints in terms of space and the requirements in respect of volume and thus it can also be made in shapes different from that shown without thereby departing from the scope of the present invention.

Claims

CLAINS

1. A clothes washing machine comprising a washing tub, a conduit which extends from the bottom of said tub and opens into an anti-clogging filter, and a discharge pump disposed downstream of said anti-clogging filter, wherein said filter is composed of two separate chambers, a first chamber and a second chamber, that the conduit opens into the filter by means of an upper aperture of the first chamber, said chambers being connected by an upper opening and an outlet hole is provided at the upper portion of an external wall of said second chamber.

2. A machine according to claim 1 wherein said anticlogging filter is a hollow body and the two chambers being separated by a substantially vertical common internal wall up to a height such as to leave said opening between the upper edge of said wall and the upper edge of the filter.

3. A machine according to claim 1 or claim 2 wherein a suitably closable hole is provided at the lower region of an external wall of the first chamber.

4. A machine according to any one of the preceding claims wherein provided in said vertical wall is a vertical slit.

5. A machine according to claim 4 wherein the slit extends the entire height of the vertical wall at a position corresponding to a lateral edge thereof.

6. A machine according to any one of the preceding claims wherein said filter is made in one piece with said conduit which connects the bottom of the tub to said anticlogging filter.

7. A clothes washing machine constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

7. A machine according to claim 6 wherein the filter is made of elastomeric material.

8. A clothes washing machine constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

Amendments to the claims have been filed as follows 1. A clothes washing machine comprising a washing tub, a conduit which extends from the bottom of said tub and opens into a hollow anti-clogging filter, and a discharge pump disposed downstream of said anti-clogging filter, wherein: said filter is composed of two separate chambers, a first chamber and a second chamber, the conduit opening into the filter by means of an upper aperture of the first chamber, said chambers being connected by an upper opening; an outlet hole is provided at the upper portion of an external wall of said second chamber; and a closable hole is provided at the lower region of an external wall of the first chamber to permit access to the interior of the first chamber to enable any objects deposited therein to be removed.

2. A machine according to claim 1 wherein said anticlogging filter is a hollow body and the two chambers are separated by a substantially vertical common internal wall up to a height such as to leave said opening between the upper edge of said wall and the upper edge of the filter.

3. A machine according to claim 1 or 2, wherein provided in said vertical wall is a vertical slit.

4. A machine according to claim 1, 2 or 3 wherein the slit extends the entire height of the vertical wall at a position corresponding to a lateral edge thereof.

5. A machine according to any one of the preceding claims wherein said filter is made in one piece with said conduit which connects the bottom of the tub to said anticlogging filter.

6. A machine according to claim 5 wherein the filter is made of elastomeric material.