GB2174110A

GB2174110A - Reducing detergent wastage in a washing machine

Info

Publication number: GB2174110A
Application number: GB08609600A
Authority: GB
Inventors: Walter Heissmeier
Original assignee: Licentia Patent Verwaltungs GmbH
Current assignee: Licentia Patent Verwaltungs GmbH
Priority date: 1985-04-25
Filing date: 1986-04-18
Publication date: 1986-10-29
Also published as: IT1204312B; FR2581092B1; FR2581092A1; IT8620172A0; DE3544788A1; DE3514933A1; GB8609600D0; GB2174110B

Abstract

A drum-type washing machine (1), the laundry drum (4) of which is mounted for rotation in a container (5) for detergent solution, has a detergent dispenser (2) for the addition of powdery and/or liquid treatment agents which are flushed out into the container (5) for detergent solution by means of the fresh water flowing in. The container (5) for detergent solution is coupled to a discharge system (6, 8, 9) which consists of a bellows-like drain outlet (6) with a vent pipe (7), a pump (8) for detergent solution and a discharge hose (9), and disposed in the drain outlet (6) is a valve device (11) which closes this during the introduction of the treatment agents. The valve device (11) is formed from resilient clack valve (16) which, when the pump (8) is inoperative, is held in the closed position by the hydrostatic water pressure (h2) in the discharge hose (9) and possibly in the vent pipe (7). <IMAGE>

Description

SPECIFICATION Drum-type washing machine The invention relates to a drum-type washing machine of the kind in which the laundry drum is mounted for rotation in a container for detergent solution, a detergent dispenser is provided for the addition of powdery and/or liquid treatment agents which are flushed out into the container for detergent solution by means of the fresh water flowing in, the container for detergent solution is coupled to a discharge system comprising a bellows-like drain outlet with a vent pipe, a pump for the detergent solution and a discharge hose, and there is disposed in the drain outlet a valve device for closing the outlet during the introduction of the treatment agent.

In the washing machines usual today, the problem still arises of achieving a better utilization of the detergents and conditioning agents used. A considerable loss of detergent may be caused, in particular, by the fact that the detergent introduced settles in the discharge system and flows away unused during the following pumping-out operation.

In order to counteract this disadvantageous phenomenon, numerous proposals have already become known but either did not lead to the desired result or were not realizable in practice.

Thus a washing machine of the type in question is known for example from the DE-GM 78 13 695 wherein disposed in the bellows-like drain outlet of the container for detergent solution is a sealing valve device consisting of a hollow plastics ball by means of which the flow of the detergent solution through towards the pump is either blocked or freed. A feed pipe, which is in communication with the fresh water supply, is connected to the pump for detergent solution. Here the fresh water running into the washing machine does not run first into the detergent dispenser but is conveyed through the feed pipe directly into the bellows-like drain outlet. When a sufficient amount of fresh water has run into the bellows-like drain outlet, the hollow plastics ball of the sealing valve device is brought into its sealing position and held in this position by the hydrostatic water pressure.Thus the entry of water into the bellows-like drain outlet from the container for detergent solution is prevented. Fresh water, and with this the treatment agent (detergent) is now supplied to the container for detergent solution. Furthermore, a washing machine is known from the DE-OS 22 29 505 having a device for preventing the loss of detergent which consists in that a certain water column, acting against the water outlet in the container for detergent solution, is constantly maintained in the drain outlet.

As already mentioned, none of these known devices yet produces the desired effect. In addition, these devices are comparatively complicated in construction and are also extremely susceptible to trouble.

It is the object of the invention to provide a drum-type washing machine having a simple device to prevent the loss of detergent and fabric softener which does not have the disadvantage existing in the prior art and which works reliably.

In accordance with the invention, in a washing machine of the kind initially referred to, the valve device is formed from a resilient clack valve which is held in the closed position by the hydrostatic water pressure in the discharge hose and possibly in the vent pipe.

The arrangement in accordance with the invention has the advantage that the valve device works more reliably and ensures a greater utilisation of the detergent than in the above mentioned arrangement of the prior art.

The invention is illustrated by way of example in the accompanying drawings, in which: Figure 1 is a diagrammatic elevation showing a drum-type washing machine in sufficient detail to explain the invention.

Figures 2 and 3 show the bottom and top of a valve support plate of the machine of Figure 1.

Figure 4 is a vertical section, and Figure 5 is a horizontal section through the valve support plate as viewed in Figure 2, and Figure 6 is a plan view of a valve flap which can be fitted on the valve support plate.

Referring to the drawings, the drum-type washing machine 1 has, in its upper region, a detergent dispenser 2 of known construction to receive powdery and/or liquid treatment agents. A fresh water supply pipe 3 to the detergent dispenser 2 is controlled, depending on a programme, by a solenoid valve, not illustrated, in the usual manner. The laundry drum 4 of the drum-type washing machine 1 is mounted for rotation in a container 5 for detergent solution. At the bottom, the container 5 for detergent solution has a bellows-like (flexible) drain outlet 6 to which a vent pipe 7 is connected.

The bellows-like drain outlet 6 establishes a connection to a pump 8 which effects the emptying of the container 5 for detergent solution and to which a discharge hose 9 is fitted. A small addition container 10 may appropriately be disposed or formed in the discharge hose 9 in order to enlarge its volume. The bellows-like drain socket 6 is equipped with a clack valve device 11, the details of which are illustrated more fully in Figures 2 to 6. This clack valve device is intended to prevent detergent from being able to get into the illustrated discharge system of the drum-type washing machine when the detergent is flushed out of the detergent dispenser 2, from which system it is conveyed into the sewer network without being used for the washing operation.

The above-mentioned clack valve device 11 in the bellows-like drain socket 6 consists of a valve support plate 12 which can be inserted in the drain outlet 6 and centred there and of which the under side 13, which is directed towards the pump 8, carries an integral mushroom 14 for buttoning on a valve flap 15 consisting of resilient material (for example rubber). For this purpose, the valve flap 15 is provided with a slot-like buttonhole 16 and, when bearing against the under side 13 of the valve support plate 12, tightly covers a flow pas sage 17 formed in this. Two pins 19,19' situated side by side are formed at the upper side 18 of the valve support plate 12.

It would also be conveivable to construct the clack valve device 11, 16 in the form of a component formed out of or on the bellows-like drain outlet 6.

The clack valve device 11 for preventing the emergence or loss of detergent from the container 5 for detergent solution works in the following manner, namely that the pump 8 (discharge pump) is controlled so that after it is switched off, the level h2 both in the appropriately dimensioned discharge hose 9 and in the vent pipe 7 is always higher, with sufficient certainty, than the highest leve h1 during any washing programme of the machine, that is to say, h2 must always be greater than hI. Thus the valve flap 15 is pressed against its valve seat by the bydrostatic water pressure occurring and the flow passage 17 in the valve support plate 12 is closed. Thus the detergent flushed out of the dispenser 2 into the container 5 for detergent solution remains in the container 5 and cannot settle in the discharge system of the washing machine.

Claims

1. A drum-type washing machine, the laundry drum of which is mounted for rotation in a container for detergent solution, which has a detergent dispenser for the addition of powdery and/or liquid treatment agents to be flushed out into the container for detergent solution by means of fresh water flowing in, and in which the container for detergent solution is coupled with a discharge system including a drain outlet, a discharge pump and a discharge hose, there being disposed in the drain outlet a valve device which is formed as a resilient clack valve which is arranged to be held in the closed position during the introduction of treatment agent into said container for detergent soiution by the hydrostatic water pressure in the said discharge hose.

2. A drum-type washing machine as claimed in Claim 1, wherein the resilient clack valve is held on a valve support plate which is centred in the drain socket outlet and has a flow passage.

3. A drum-type washing machine as claimed in Claim 2, wherein the resilient clack valve is secured to the valve support plate by buttoning on.

4. A drum-type washing machine as claimed in Claim 2 or 3, wherein a mushroom is formed on or at the valve seat side of the valve support plate.

5. A drum-type washing machine as claimed in any one of Claims 2 - 4 wherein pins are provided at or formed on the side of the valve support plate remote from the valve side.

6. A drum-type washing machine as claimed in any preceeding Claim, wherein a slot-like buttonhole is provided in the clack valve, which is formed as a resilient valve flap.

7. A drum-type washing machine as claimed in Claim 1, wherein the discharge hose has a section of increased volume.

8. A-drum-type washing machine as claimed in Claim 1, wherein the valve device is a component formed from or on a bellows-like drain socket.

9. A drum-type washing machine substan.ially as described herein with reference to the accompanying drawings.