GB2111537A

GB2111537A - Automatic washing machine

Info

Publication number: GB2111537A
Application number: GB08233397A
Authority: GB
Inventors: Flavio Campagnolo
Original assignee: Industrie Zanussi SpA
Current assignee: Industrie Zanussi SpA
Priority date: 1981-12-14
Filing date: 1982-11-23
Publication date: 1983-07-06
Also published as: FR2517951A3; FR2517951B3; IT8134057V0; ES267688U; DE8230454U1; GB2111537B; ES267688Y

Abstract

An automatic washing machine is provided with a decalcifier 11 which, during one phase of the operating cycle of the machine is regenerated by being flushed through with water which has passed through a salt container 12. The water for this regeneration phase comes from a tank 8 which has an internal basin arrangement 17 which in other phases of the machines' operation returns water from the free air-gap arrangement 6 at the inlet end of the water feed circuit to the tub 4. The decalcifier 11 discharges into the tub 4 via a one-way-valve 10 and the discharge side of a pump 20 of the machine. In order to initiate the regeneration of the decalcifier 11, the pump 20 is operated at the same time as the water inlet valve 5 is opened. The operation of the pump 20 causes the one-way valve 10 to close and this in turn causes the interior of the tank 8 below the basin 17 to fill with a predetermined amount of water. The pump 20 is then stopped enabling the valve 10 to open and thus the water which has accumulated in the tank 8 to discharge via the salt container 12 and a one way valve 13 through the decalcifier 11. <IMAGE>

Description

SPECIFICATION Automatic washing machine The present invention relates to an automatic washing machine, in particular of domestic type, with an improved water feed circuit.

British Patent Application No. 81 34257 of the present applicants describe an automatic washing machine wherein the water feed circuit comprises an electrically operated intake valve, a free air gap section, a decalcifier and a salt container. The salt container has an outlet connected to the decalcifier and an inlet connected to a tank for metering the decalcifier regeneration water. The tank communicates in its upper part with the outside ambient air and with the air gap section.

The feed circuit further comprises a closure member controlled by a pump of the washing machine, for closing the circuit in a phase of the machine's operating cycle, prior to regeneration of the decalcifier, in which the electrically operated intake valve is open.

With such a design, it is possible to avoid using a further electrically operated valve for controlling the decalcifier regeneration phase in a region of the water circuit which is subjected to high pressures or which involves salt water, which can cause the electrically operated valve to jam or clog.

On the other hand, the closure member, which is formed by a resilient bellows-type member connected to the discharge of the pump, may suffer in time from deposits of dirt which tends to limit the opening and closing movements of the closure member. Consequently, the reliability of the bellows-type element, while being greater than that of a normal electrically operated valve, is still not completely satisfactory.

According to the present invention, there is provided an automatic washing machine provided with a water feed system comprising a controlled intake valve, a free air gap section and a decalcifier connected to the outlet of a salt container, the intake of which is connected to a tank communicating with the outside ambient air and with said air gap section, for metering the decalcifier regeneration water, a closure member being provided, controlled by a pump of the machine for at least partially closing said circuit in a phase of operation of the machine in which the intake valve is open, the closure member comprising a non-return valve disposed in the water feed circuit, the latter being connected to the discharge side of said pump.

Therefore, the washing machine according to the invention is provided with a feed water pump which, for controlling the decalcifier regeneration phase, in place of delicate electrically operated valves, only requires a closure member which is simple in actuation and reliable in operation, being self-cleaning.

Features and advantages of the present invention will be more clearly apparent from the following description given solely by way of nonlimiting example with reference to the accompanying drawings in which: Figure 1 is a diagrammatic view of the feed water system of a preferred embodiment of the washing machine according to the invention, Figures 2 and 3 are diagrammatic views on an enlarged scale of a detail of part of the circuit shown in Figure 1, in two operating positions.

Referring to Figure 1, the washing machine comprises a feed pipe 9 for connecting the water main to the washing tub 4 of the machine by way of the series arrangement of an electrically operated intake valve 5, a free air gap section 6, a decalcifier 11, a non-return valve 10 and the discharge or casing of a discharge pump 20.

Where the washing machine is a dish washing machine, the water feed circuit may be connected to the discharge of the discharge pump or to the discharge of the circulating pump.

In particular, the non-return valve 10 is normally open with respect to the flow of water through the pipe 9, as shown in Figure 2.

The water feed circuit of the washing machine further comprises a salt container 12 having an outlet connected to the decalcifier 11 by way of a further non-return valve 13 and an inlet connected by way of a conduit 14 to the bottom of a metering tank 8. In substance, the tank 8 may be of the type described in above-mentioned British Patent Application No.8134257 filed on 28.11.1 980 by the present applicants. In particular, the tank 8 comprises a basin arrangement 17 which communicates at its top with the rest of the interior of the tank and which is disposed below the air gap 6 to collect normal water losses.The bottom of the basin arrangement 17 communicates with an overflow conduit 1 5 and thus with the tub 4 by way of a calibrated hole 18 having a capacity substantially corresponding to the above-mentioned losses at the air gap 6. The tank 8 also communicates with the outside ambient air via an opening 16 in the overflow conduit 15.

The mode of operation of the washing machine is known and will not be described herein. It should only be pointed out that the pump 20 is actuated for a certain period of time by the programmer (not shown) of the machine during a phase immediately prior to regeneration of the decalcifier 11, in which the electrically operated intake valve 5 is actuated into an open position.

In that phase, the non-return valve 10 receives from the discharge of the pump 20, a hydraulic pressure which is higher than and opposite to that of the flow of water from the water main, whereby the valve 10 moves into the closed position as shown in Figure 3. The feed conduit 9 is therefore closed, whereby substantially all the water from the water main overflows from the air gap section 6 into the basin arrangement 17, with a flow capacity which is substantially greater than that of the hole 18. The water overflows rapidly from the basin arrangement 17, filling the metering tank 8; any excess water overflows into the tub 4 by way of the conduit 1 5.

After a certain period of time, the electrically operated valve 5 is re-closed and the pump 20 switched off, whereby the non-return valve 10 can re-open, initiating the regeneration phase of the decalcifier 11. The water collected in the tank 8 flows under the force of gravity through the salt container 12, the valve 13, the decalcifier 11 and the valve 10 and passes into the washing tub 4 by way of the casing of the pump 20.

It should be noted that the flow of water which, in operation of the washing machine, repeatedly passes through the conduit 9, keeps the valve 10 continually cleaned, whereby the valve can operate in the above-described manner with the desired degree of reliability.

It will be appreciated that the washing machine described may be the subject of any modifications, according to circumstances, within the scope of the appended claims. For example, the feed conduit 9 may pass into the washing tub 4 without passing through the pump 20, to the discharge of which however it is still connected.

Claims

1. An automatic washing machine provided with a water feed system comprising a controlled intake valve, a free air gap section and a decalcifier connected to the outlet of salt container, the intake of which is connected to a tank communicating with the outside ambient air and with said air gap section, for metering the decalcifier regeneration water, a closure member being provided, controlled by a pump of the machine for at least partially closing said circuit in a phase of operation of the machine in which the intake valve is open, the closure member comprising a non-return valve disposed in the water feed circuit, the latter being connected to the discharge side of said pump.

2. A washing machine according to claim 1 wherein the non-return valve is disposed in the feed water circuit upstream of its connection to the discharge side of the pump and is normally open with respect to the flow of feed water through said circuit.

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