GB2181748A - A water flow safety device for a household appliance - Google Patents

Abstract

A water flow safety device for a dishwashing or laundry washing machine comprises a fresh water inlet stub pipe (3), which is securable to a shut-off cock by a box nut (4), a first outlet stub pipe (5) for connection of a supply hose (6), and a pressure-operable permanent magnet shut-off valve (14) and an electromagnetic filling valve (15) arranged in series in a duct (11) connecting the two stub pipes (3,5). Also present are a drainage water inlet stub pipe (7) and a control duct connection (17) to a pressure element (16) of the shut-off valve (14), the control duct connection (17) being connected by way of a pressure hose (18) with a pressure chamber or the like of level-regulating equipment of the appliance. The supply hose (6), drainage hose (8) and pressure hose (18) all extend through a leakage water hose (10), which is connected to an enlarged stub pipe (9) of the safety device. <IMAGE>

Description

SPECIFICATION A water flow safety device for a household appliance The present invention relates to a water flow safety devicefora household appliance, for example a dishwashing machineora laundrywashing machine.

In DE-PS 31 14 664, there is described a protective device for a water-conducting household appliance, the device comprising a shut-offvalve which is connected in series with a water supply valve of the appliance and control ofwhichtakesplacethrougha float-actuated permanent magnet arranged exter nally ofthe valve housing. Arranged on the valve housing ofthis double valve, which is at the side of the appliance, is a pressure element which detects the water level in a rinsing container ofthe appliance and a diaphragm of which at one side carries a permanent magn#and at its otherside is coupled with a float in such a mannerthatthe float deflects the valve diaphragm on the occurrence of leakage water in a collecting trough atthe bottom side ofthe appliance.

The water supply into the rinsing container ofthe appliance takes place through openingoftheelectro- magnetically controlled supplyvalve ofthe appliance and switched by the appliance control. On attainment of the operational level in the rinsing container, a level monitor effects closing of the electromagnetic supply valve. On failure ofthe level mon itororon non-closing ofthe electromagnetic supply valve, the liquid level inthe rinsing container reaches a safety level at which the diaphragm, indirectly subjected to the pressure of the water, of the pressure element lifts a permanent magnet so farfrom its armature in the valve housing that the shut-off valve blocks the further supply of water.In this device,the supply hose is constantly subjected to mains water pressure when the shut-off cock is open.

In DE-PS 30 14427 there is disclosed a safety device with a leakage water hose which, on rupture of the supply hose, conducts water issuing therefrom into a collecting trough arranged at the bottom ofthe appliance, where a switching device promptly initiates shutting off of the water supply. The switching device can be a float-controlled switch, by means of which, when water leakage occurs, the supplyvalve is closed and/or an emptying pump ofthe appliance is switched on, which is connected through a drain- age hose with a discharge.If the supply valve connected to a mains shut-off cock consists of an electromagnetic valve actuable bythecontrol equipment of theappliance,thenthemagnetcoil ofthesupply valve is connected through an electrical line with the control equipment,forexamplethe program control device and/or a switching device in the leakage water collecting trough ofthe appliance. The supply valve is secured by its inlet stub pipe to the outletofthe shut-off cock, while fastened to its outlet stub pipe is the supply hose which leads by way of a safety valve at the side ofthe appliance into the rinsing container of the appliance.Also extending from the supply valve is the leakage water hose which is fastened by means of a hose clamp to the supply valve housing, receives the supply hose and opens freely into the collecting trough.

The connection ofthe appliance can be simplified and facilitated if the supply hose, leakage water hose and drainage hose are incorporated into one pipe, in which the control line between the appliance and the appliance-controlled supply valve atthe mains shutoff cock can also be included. Forthis purpose, the supply valve, connected by an inlet stub pipe to the shut-off cock, has an outlet stub pipe for the supply hose, an enlarged connecting stub pipe, arranged around this outlet stub pipe,forthe leakgewater hose, a second inlet stub pipeforthe drainage hose and a second outlet stub pipefora drainage hoseextension to a discharge.In that case, the second inlet stub pipe ofthe supply valve forthe drainage hose and the second outlet stub pipe for the drainage hose extension can be connected together by a housing channel ofthesupplyvalve.

Thereisscopeforfurtherimprovementofthedescribed safety device in the sense that a separate arrangement of the appliance-controlled supply valve at a shut-off cock or a mechanical permanent magnet-controlled safety valve in a collecting trough atthe bottom ofthe appliance are avoided, as well as dispensing with an electromagnetically controlled supplyvalveintheappliance.

According to the present invention there is prov ided a water flow safety device for a household appliance,the device comprising afirstinletstubpipe couplable by coupling meanstofreshwatersupply means, a first outlet stub pipe connected to thefirst inlet stub pipe bywayofa supply duct and connectible to a water supply hose of the appliance, a pressure-operable shut-offvalve and an electromagnetically operable filling valve arranged in series in the duct, connecting meansconnectibletoawaterdrain- age hose of the machine, a pressure stub pipe connected to a pressure element of the shut-offvalve and connectibleto a pressure hose from water level regulating means ofthe appliance and an enlarged secondoutletstub pipeconnectabletoa leakage water hose and so arranged that in use said supply hose, drainage hose and pressure hose will pass through said leakage water hose when connected to the second outlet stub pipe.

Such a device may have a simple and readily assembled construction and atthesametimefulfil safety requirements in respect of water damages due to bursting ofthesupplyhoseand/orthedrainage hose. Since the level filling of a rinsing container of the appliance can be controlled by the valve com bi nation, arranged in the device, of shut-off valve and electromagneticfilling valve, this valve combination, which can be controlled by the program switching unit ofthe appliance, makes redundant a controllable fresh water inletvalve inthe appliance itself. If the rinsing container is empty and the level-regulating equipment is thus unloaded, whereby a pressure el ementofthe shut-offvalve of the device does not stand under pressure, then the shut-off valve is opened by, for example, a permanent magnetthereof.

When the appliance is put into operation,then vol- tage is applied to the electromagneticfilling valve likewise in the water-filling stages ofthe appliance operating program and opened eitherfora predetermined time or until a level switch responds. Shouldthefilling level ofthe rinsing container reach a safety level, then the shut-offvalve is closed and the water supply to the appliance is interrupted through the level-regulating equipment and the pressure element. When voltage supply to the electromagnetic filling valve is interrupted by the program, this valve assumes its closed position.Since the supply hose is free of pressure when the filling valve is closed as well as when the shut-offvalve is closed, bursting of the supply hose is virtually excluded even if the oper atorleavestheshut-offcockopen.

Since the leakage water hose envelopes the supply hose and the drainage hose and the hose connections are disposed ata common housing of the shut-offvalve and filling valve and the device isfastenable atthe first inlet stub pipethrough, forexample, a box nut to the shut-off cock, the device is simple to connect.

If the appliance is equipped with a leakage water collecting trough arranged at the bottom ofthe appliance, as well as with a float orthe like arranged in the trough and a switching device actuable by the float and connected byan electrical control linetothe magnet coil ofthefilling valve, then a monitoring of the state of the supply hose and drainage hose and of the appliance itself is possible.Forthis purpose, the leakage water hose is at one end firmly andtightly connected at a housing of the safety device, whilst it opens by its other end freely into the drainage trough. If supply hose were to start to leak during a filling program step orthe drainage hose were to leak during a pumping-out program step, then the leaking waterwould be received by the leakage water hose and conducted into the collecting trough, as a result of which the switching device could promptly initiate closing ofthe filling valve or switching-off of the emptying pump.A leakage within the machine or failure ofthe shut-off valve monitoring thefilling level oftherinsingcontaineralsowould notleadto flooding of the installation space. A further protection results from the fact that the electromagneticfilling valve is closed in the current-free state.

In a simplified construction ofthe appliance without collecting trough and float-actuated switching device, the leakage water hose can open into the level-regulating equipment orthe rinsing container ofthe appliance. A pressure element of the shut-off valve can be actuated through the leakagewater, which is conducted from the leakage water hose into monitoring equipmentforthe rinsing water level, by way of the level-regulating equipment in such a mannerthatthe shut-offvalve is closed when the set filling level is reached. A corresponding switching operation would be initiated at the latest on the attainmentofthe normal or safety level in case the rinsing container itself is filled by leakage water.

Embodiments ofthe present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Figure 1 is a sectional view of a first device emb odying the invention; Figure2 is a sectional view of a second device emb odying the invention; Figure3is a cross-section through a hose group connected to the device of Figure 1; and Figure4is a cross-section through a hose group connected to the device of Figure 2.

Referring now to the drawings there is shown in each of Figures 1 and 2 a safety device 1 which is to be connected to a shut-off cock of locally fixed water mains and which comprises a housing 2 with a fresh water inlet stub pipe 3 and a box nut 4. Disposed ata wall ofthe housing 2 opposite the inlet stub pipe 3 is afirst outlet stub pipe 5,towhich a supply hose6 is fastenable, a drainage water inlet stub pipe 7,to which adrainagehose8isfastenable,andanenlar- ged connecting stub pipe 9, also encompassing the stub pipes 5 and 7, for a leakagewater hose 10.

A mechanically actuable shut-off valve 14 and an electromagneticfilling valve 15 are arranged downstream of a course sieve 12 and a valve sieve 13, in a supply channel 11 which extends in the housing 2 from the stub pipe 3to the stub pipe 5,the valve 14 being disposed atthe valve entry and the valve 15 at the valve exit. In this arrangement, in the case of leakage atthe filling valve, the function of the shut-off valve, which is closed servo-supported by the water duct pressure, is ensured. An advantageous construction ofthe device 1 is achieved through an arrangement, in alignment or displaced in parallel lines, ofthe inlet stub pipe 3 with the outlet stub pipe 9orthevalves 14 and 15.

The mechanically actuable shut-offvalve 14 has a pressure element 16, which is connected in air-tight manner by way of a control line connection 17 and a hose 18 to a pressure chamber, set to afilling level of a rinsing container of a household appliance, of a level-regulating equipment. The hose 18 is preferably conducted in a hose group 19, enveloped bythe leakage water hose 10, with the supply hose 6 and drainage hose 8. In the rest position, the shut-off valve 14 is held in the opened position, for example, by a permanent magnet, a spring orthe like acting on a diaphragm of the pressure element 16.When the filling stateofthe rinsing containerreachesafilling or safety level, then the pressure acting by way of the pressure chamber ofthe level-regulating equipment and the hose duct 18 on the pressure element 16 closes the shut-offvalve 14 and stops furtherwater supplytothe rinsing container. When the rinsing container is emptied and the pressure element relieved, the shut-offvalve again opens.

The hose group 19 also includes an electrical line 20, which extends from the electric system ofthe appliance and is conducted to the electromagnet coil of the filling valve 15 by way of the connecting stub pipe 9. The filling valve, which is closed in thevoltage-free state, is controlled by way of a program control of the appliance and opened for a limited period in the water supply program steps. Whilstthe supply hose 6 is led to the rinsing container of the appliance, the drainage hose 8 is connected atthe appliance to an emptying pump and the leakage water hose 10 enveloping both these hoses can, in one arrangement, open freely into a leakage water collecting trough arranged atthe bottom ofthe appliance.Arranged in the collecting trough is a float which on the occurrence of leakage water effects closing ofthefilling valve 15 byway of a switching device.

In another arrangement, the leakage water hose can be conducted to the level-regulating equipment orintothe rinsing container so that the leakagewater initiates closing of the shut-offvalve 14 by way of the level-regulating equipment and the pressure element 16.

According to Figure 1, an elbow 23, a connecting channel orthelike,which connectsthedrainage water inlet stub pipe 7 for the drainage hose 8 with a second outletstub pipe 21 foradrainagehoseexten- sion 22, is provided in the housing 2. The extension 22 conducts the rinsing liquid from the device 1 into the locally fixed drainage water mains.

According to Figure 2, the drainage hose 8 ora drainage hose extension issues from the housing 2, without change in direction, behindtheenlarged connecting stub pi pe 9. The hose 8 can beconducted along the housing 2 by means of a hose clamp 24 or the like fastenable to the housing 2.

In order to provide an orderly and space-saving disposition of the supply lines ofthe appliance, the hose group 19 can be combined with a mains cable 25 of the appliance. Forthis purpose, the hose 10 can be provided at its wall with a groove which is formed by resilient tongues 26 and into which the mains cable 25 is insertable overthe desired length. For transport of the appliance, it is advantageous if the housing 2 has a dummy plug socket, bores orthe like forthe reception of a plug 27 ofthe mains cable.

Claims (12)

1. Awaterflowsafetydevicefora household appliance,thedevicecomprising afirstinletstub pipe couplableby coupling means to fresh water supply means, a first outlet stub pipe connected to the first inlet stub pipe by way of a supply duct and connectibleto a water supply hose ofthe appliance, a pressure-operable shut-off valve and an electro magnetically operable filling valve arranged in series in the duct, connecting means connectible to a water drainage hose ofthe machine, a pressure stub pipe connected to a pressure element of the shut-off valve and connectibleto a pressure hose from water level regulating meansoftheapplianceandanenlarged second outlet stub pipe connectibleto a leakage water hose and so arranged that in use said supply hose, drainage hose and pressure hose will pass through said leakage water hose when connected to the second outlet stub pipe.

2. A device as claimed in claim 1, wherein the device comprises a housing and the first outlet stub pipe, the connecting means, the pressure stub pipe and the second outlet stub pipe are arranged in alignment or in parallelly displayed planes and at a side of the housing opposite a side thereof at which the first inlet stub pipe is arranged, the shut-offvalve and filling valve being arranged in corresponding align mentwithin the housing.

3. Adevice as claimed in claim 2,whereinthe connecting means and the second outlet stub pipe areso arranged that in use said drainage hose ora discharge extension thereof extend out of said water leakage hose and alongside a housing ofthe device.

4. A device as claimed in claim 3, comprising hose guidance means arranged atthe housing to guide said drainage hose or extension thereof.

5. A device as claimed in claim 1, the connecting means comprising a second inletstub pipe connectible to said drainage hose and the device further comprising a third outlet stub pipe connectibleto a water discharge hose.

6. A device as claimed in claim 1, comprising an elbowconnectingthesecond inletstubpipetothe third outlet stub pipe and arranged in a housing of the device.

7. A device as claimed in any one of the preceding claims, comprising an electrical power supply cable electrically connected to the filling valve and extending through the second outlet stub pipe.

8. A device as claimed in claim 1, comprising a housing provided with locating means for an electrical plug.

9. A device substantially as hereinbefore described with reference to Figures 1 and 2 ofthe accompanying drawings.

10. A device substantially as hereinbefore described with reference to Figures 3 and 4 ofthe ac- companying drawings.

11. Household water conducting equipment comprising an appliance and a device as claimed in any one of the preceding claims and connected by said hoses to the appliance.

12. Equipment as claimed in claim 1 1,the appli- ance being one of a dishwashing machine and a laundry washing machine.