GB2111021A

GB2111021A - Liquid dispenser

Info

Publication number: GB2111021A
Application number: GB08234751A
Authority: GB
Inventors: Robert Edward Hargreaves
Original assignee: Hotpoint Ltd
Current assignee: Hotpoint Ltd
Priority date: 1981-12-04
Filing date: 1982-12-06
Publication date: 1983-06-29
Also published as: GB2111021B

Abstract

A dispenser for feeding metered quantities of a liquid from a reservoir (2) into a receptacle (1), has a dispensing chamber (3) into which the liquid can be fed under gravity from the reservoir. The chamber has a first outlet pipe (8) leading to a part of the receptacle below the chamber from a position at or near the base of the chamber and a second outlet pipe (7) leading to a part of the receptacle above the chamber from a position at or near the top of the chamber. The pipes pass from the chamber to the receptacle above the maximum level of liquid in the reservoir. (5) A second liquid, such as water, is fed into the chamber from an inlet (5) under pressure to mix with the first liquid in the chamber and force it into the receptacle, and a valve (6) between the reservoir and the dispensing chamber is arranged to close during the introduction of the second liquid into the chamber. The dispenser may be used, for example, for introducing liquid fabric conditioner or liquid detergent into the wash drum of an automatic clothes washing machine. <IMAGE>

Description

SPECIFICATION Liquid dispenser This invention relates to dispensers for discharging metered quantities of a liquid from a reservoir, and is especially, through not exclusively, concerned with such dispensers used for the introduction of liquid fabric conditioner or liquid detergent intothe wash drums of automatic clothes washing machines.

According to the invention a dispenserforfeeding metered quantities of a liquid from a reservoir into a receptacle, comprises a dispensing chamber, a passage enabling the liquid to be fed from the reservoir to the dispensing chamber under gravity, a first outlet pipe leading from a position at or near the base of the chamber to a region of the receptacle below the chamber, a second outlet pipe leading from a position at or near the top of the dispensing chamber to a region of the receptacle above the chamber, which pipes pass from the chamber to the receptacle above the maximum level of liquid in the reservoir, an inlet through which a second liquid is arranged to be fed into the chamber under pressure so as to mix with the first liquid in the chamber and force it through the outlet pipes into the receptacle, and a valve arranged to close to prevent the flow of liquid through said passage during the introduction of the second liquid into the chamber.

In use of such a dispenser the size of the dispensing chamber is selected to enable a predetermined quantity of the first liquid to be fed into the receptacle with each flow of the second liquid, which may, for example, be water. At the cessation of flow the remaining liquid in the chamber will syphon from the chamber into the receptacle through the first outlet pipe, air entering the chamber through the second outlet pipe and permitting the syphoning action. Opening of the valve when the flow of the second liquid is cut off allows the chamber to be re-filled with the first liquid from the reservoir, and the process can then be repeated.

Conveniently the valve is closeable automatically by the flow of the second liquid into the dispensing chamber.

The rate at which the first liquid is fed into the dispensing chamber from the reservoir when the valve is opened is arranged to be sufficiently lower than the rate at which liquid syphons from the chamber into the receptacle, as to result in a virtually complete emptying of the chamber by the syphoning process, and consequently in an interruption of the process, thus allowing the dispensing chamber to be re-filled with liquid from the reservoir.

The dispensing chamber is thus emptied of the first liquid each time the second liquid is allowed to flow into the chamber, and by suitably selecting the size of the chamber, and the number of times the second liquid is introduced into it, the amount of the first liquid fed into the receptacle can readily be controlled.

Control of the flow of the second liquid into the dispensing chamber is conveniently effected by a solenoid valve which, for some applications at least, may be operated automatically by a suitable control circuit.

The reservoir may, for example, consist of a flexible bag which inflates when liquid is introduced into it, and gradually collapses as the liquid is successively discharged into the dispensing chamber. By this means the amount of air which can contact the surface of the liquid is restricted. This is of particular advantage in the case of fabric conditioners and other liquids which tend to form a skin when exposed to air.

Thus the invention is particularly applicable to the dispensing of fabric conditioners into the wash drums of automatic clothes washing machines.

Moreover by using a flexible bag as the reservoir, its assembly within the washing machine cabinet is facilitated, as it can readily be hung against a wall of the cabinet, this having the further advantage that it will remain relatively cool in operation of the machine, thus ensuring storage of the conditioner at a substantially even temperature.

Access to the reservoir for filling purposes can readily be effected by means of a flap-covered opening in, say, the front panel of the washing machine. Filling of the reservoir may then be achieved directly from a bottle of conditioner, fitted if necessary with a tubular extension.

One embodiment of the invention for use in dispensing controlled quantities of a fabric conditioner into the wash drum of an automatic clothes washing machine will now be described by way of example with reference to the accompanying schematic drawing.

The wash drum 1 is of generally cylindrical shape mounted with its axis horizontal, and has mounted within it, in the usual way, an inner perforated drum (not shown) arranged to rotate at a relatively low speed for performing a washing or rinsing operation, and at a higher spin speed at appropriate times for extracting liquid from clothes or other articles being washed.

During final rinsing of the clothes it is frequently desired to introduce a fabric conditioner into the wash drum. In the machine illustrated the conditioner in liquid form is stored in a reservoir 2, from which metered quantities of the conditioner are arranged to be fed into the wash drum 1, mixed with a quantity of water, by means of a dispensing chamber3.

The reservoir 2 is located above the dispensing chamber 3 and is connected to the top of the chamber by a pipe 9 so that the conditioner can flow into the chamber from the reservoir under gravity, through a valve 6 whose function will be subsequently described.

The dispensing chamber 3 is connected to the washing drum 1 by means of two further pipes 7, 8 which pass to the drum above the highest level of conditioner in the reservoir 2.

The pipe 7 extends from the top of the dispensing chamber 3 to the top of the wash drum 1, and the pipe 8 extends from a region adjacent the bottom of the chamber 3 to a lower part of the wash drum, located at a level below that of the base of the chamber 3.

A further pipe 5 is arranged to feed water into the chamber 3 under pressure through a solenoid valve 4, the pipe 5 extending through the base of the chamber 3 in alignment with the pipe 9 which connects the chamber with the reservoir2. The valve 6 is in the form of an inverted cone 11 with a downwardly projecting tubular skirt 12, which fits loosely over the top of the pipe 9 within the chamber.

The sequence of operations of the dispenser is as follows. Fabric conditioner from the reservoir 2 initiallyfiows down the pipe 9, past the valve 6, into the dispensing chamber 3, and also fills the outlet pipes 7 and 8 to the level of conditioner C within the reservoir. When the washing machine control system requests fabric conditioner, the solenoid valve 4 is energised which causes water to flow under pressure in the direction indicated by the arrow A.

The flow of water from the pipe 5 causes the valve 6 to rise, thereby blocking off the outlet from the pipe 9.

The water enters the chamber 3 through the gap between the pipe 5 and the skirt 12 of the valve 6, flowing downwards towards the bottom of the chamber and mixing with the fabric conditioner in the chamber, the mixture being fed into the wash drum 1 through the pipes 7, 8. The flow of water is continued for a sufficient length of time to ensure that the chamber 3 and the pipes 7 and 8 are thoroughly flushed of conditioner.

The solenoid valve 4 is then de-energised and the flow of water stops; as air can enter the top of the chamber 3 through the tube 7, it allows water remaining in the chamber to syphon into the drum 1 through the pipe 8. At the same time the valve 6 drops back on to the pipe 5 and allows the chamber 3 to re-fill with fabric conditioner, the rate of flow of the conditioner into the chamber being sufficiently below that at which liquid is discharged from the chamber by the syphoning process to ensure that the chamber is virtually completely emptied and the process terminated.

Thus the dispensing chamber 3 may be arranged to be cleared in about three seconds and to be re-filled with conditioner, in readiness for the next operation, in about ten seconds.

The volume of the dispensing chamber is conveniently 30 ml, thus giving possible charges of conditioner of 30 ml, 60 ml or 90 ml according to whether one, two or three operations of the system are used, although it will be understood that more than three operations and/or chambers of other volumes, could be used if desired.

The reservoir 2 conveniently comprises a flexible container such as a thin-walled bag of polyethylene, which enables, as far as possible, air to be excluded from the surface of the conditioner, the bag becoming inflated as it is filled and collapsing as the condition is discharged.

The reservoir 2 can be located adjacent the front wall of the washing machine cabinet with access to it, for filling purposes, provided by a flap-covered opening. Use of a relatively wide, rather than a deep reservoir ensures that there is little variation in the height of liquid in the tubes 7, 8 as the level in the reservoir changes, thus ensuring that the volume of conditioner delivered to the wash drum 1 does not significantly vary. Thus although the volume of conditioner delivered depends primarily on the volume of the dispensing chamber 3 the attendant volume of liquid in the tubes 7, 8 will also be included in the amount actually delivered to the drum.

By arranging the reservoir 2 at or near the top of the washing machine cabinet so that the conditioner is discharged into the dispensing chamber 3 under gravity, and by utilising water from an external supply to feed the conditioner from the chamber into the wash tub, the complications of other dispensing systems, including the need for a pump, are effectively avoided.

A level indicator may be associated with the chamber 3 and/or reservoir 2 to provide a user with an indication of the quantity of conditioner in the system. Such an indicator may be provided by a transparent window through which the conditioner level can be viewed directly.

The front wall of the chamber 3 may also be provided with a normally closed door which, in the closed position, seals against the rim of an opening through which access to the interior of the chamber may be obtained for servicing purposes by opening the door.

In some cases the machine may incorporate a further pipe to permit water to be fed into the reservoirforflushing purposes as a controlled operation, for example prior to re-filling with a fresh change of conditioner, following the emptying of the reservoir.

In washing machines designed for use with a liquid detergent a similar form of dispensing arrangement may be used for feeding controlled quantities of the detergent into the wash drum.

However the invention is not restricted to use with washing machines, but also has other applications where controlled quantities of a liquid are required to be dispensed in a simple, reliable manner.

Claims

1. A dispenser for feeding metered quantities of a liquid from a reservoir into a receptacle comprising a dispensing chamber, a passage enabling the liquid to be fed from the reservoir to the dispensing chamber under gravity, a first outlet pipe leading from a position at or near the base of the chamber to a region of the receptacle below the chamber, a second outlet pipe leading from a position at or near the top of the dispensing chamber to a region of the receptacle above the chamber, which pipes pass from the chamber to the receptacle above the maximum level of liquid in the reservoir, an inlet through which a second liquid is arranged to be fed into the chamber under pressure so as to mix with the first liquid in the chamber and force it through the outlet pipes into the receptacle, and a valve arranged to close to prevent the flow of liquid through said passage during the introduction of the second liquid into the chamber.

2. A dispenser according to Claim 1 wherein the valve is closeable automatically by the flow of the second liquid into the dispensing chamber.

3. A dispenser according to Claim 1 or 2 wherein rate at which the first liquid is fed into the dispensing chamber from the reservoir when the valve is opened in use of the dispenser is arranged to be sufficiently lower than the rate at which liquid syphons from the chamber into the receptacle, as to result in a virtually complete emptying of the chamber by the syphoning process, and consequently in an interruption of the process, thus allowing the dispensing chamber to be re-filled with liquid from the reservoir.

4. A dispenser according to Claim 1,2 or 3 including a solenoid valve for controlling the flow of the second liquid into the dispensing chamber.

5. A dispenser according to any preceding Claim wherein the reservoir consists of a flexible bag which inflates when liquid is introduced into it, and gradually collapses as the liquid is successively discharged into the dispensing chamber.

6. An automatic washing machine incorporating a dispenser according to any preceding Claim for dispensing a fabric conditioner into the wash drum of the machine.

7. An automatic washing machine according to Claim 6 in which the reservoir consists of a flexible bag wherein the bag is hung against a wall of the washing machine cabinet.

8. An automatic washing machine according to Claim 7 wherein the flexible bag is located adjacent the front wall of the cabinet, and the latter is provided in said front wall with an opening through which fabric conditioner may be introduced into the bag.

9. An automatic washing machine incorporating a fabric conditioner dispenser substantially as shown in and as hereinbefore described with reference to the accompanying drawing.