GB2164422A

GB2164422A - Safety device for a water-conducting household appliance

Info

Publication number: GB2164422A
Application number: GB08516915A
Authority: GB
Inventors: Ernst Stickel; Helmut Jerg
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-09-14
Filing date: 1985-07-04
Publication date: 1986-03-19
Also published as: DE3433904C1; IT1185681B; FR2570462B1; GB8516915D0; IT8522883V0; GB2164422B; FR2570462A1; IT8522050A0

Abstract

A safety device for a water-conducting household appliance, particularly a dishwashing machine or laundry washing machine, comprises a shut-off valve (1) actuable through a float (10) by way of a pressure element (2), wherein a pressure plate (3) of the pressure element carries a valve push rod (4) which at its free end has a shoulder (5). The shoulder (5) is engaged by a first arm (6) of a double-armed lever, which is mounted at the valve housing (45) and the second arm (7) is connected with the float (10) arranged in a leakage water collecting trough (8) of the appliance. On raising of float (10) the first lever arm (6) moves the rod (4) downwardly to close the valve (1) without free play between arm (6) and rod (4). On pressure exerted a diaphragm (47) from an air chamber subject to liquid level in the operating or rinsing container, the rod (4) moves downwardly relative to the arm (6) to close the valve (1). Spring (11) on rod (4) biases the rod in the valve closing direction and prevents said free play. Alternatively, the spring may act between the float (10) and the second lever arm (7). <IMAGE>

Description

SPECIFICATION Safety device for a water-conducting household device The present invention relates to a safety device for a water-conducting household appliance.

In DE-PS 31 14 664 there is disclosed a safety device comprising a spigot which is provided on a pressure plate of a ualue-actuating pressure element and which has a constriction which at one side passes over into a shoulder. The constriction is embraced by a forked end of one arm of a double-armed lever, the other arm of which is connected with a float in a leakage water collecting trough. Due to production tolerances resulting from, in particular, the fastening of the valve to a housing mount of the household appliance, different positions of the float in the trough or different initial positions of the connecting elements between the float and the valve push rod formed by the spigot result.

On the one hand, the float can rest on the trough and, through its suspension and even without leakage water in the trough, load the spigot for the biassing of the pressure element so far that the valve is closed. On the other hand, due to production tolerances in the float suspension, the lever position can result in such a spacing between the shoulder of the spigot and the associated lever arm fork end that a certain level of leakage water in the trough is necessary to bridge over this spacing, the valve being actuable for closing only. throu gh in gress of further leakage water into the trough. Consequently, a higher leakage water level is necessary for the switching operation, particularly when a certain lever translation ratio is provided. This can lead to water over flowing the trough without the valve having been closed.An additional testing and adjusting station in the production of the appliance is therefore ne cessary after the assembly of the safety device.

It would thus be desirable to provide a safety device whereby production and assembly tolerances can be compensated for simply and free of problems during the installation into the appliance.

According to the present invention there is provided a safety device for a water-conducting household appliance, comprising a shut-off valve, a valve-actuating device with a pressure member responsive to pressure to cause the valve to be shut, a float to be arranged in a leakage water collecting trough of the appliance, and a double-armed lever so connected at a first arm thereof to an actuating rod of the pressure member and at the second arm thereof to the float as to translate upward movement of the float into movement of the rod in a direction effecting operation of the pressure member for closure of the valve, the first arm of the lever being coupled to the rod to be free of play relative thereto in said direction of rod movement by the lever but to permit movement of the rod relative to the arm on response of the pressure member to pressure.

In the installed position of such a safety device in a household appliance, the float can rest on the bottom of a leakage water collecting trough and the first arm of its lever engage free of play at the rod in such a manner that the rod is actuated by the lever in the direction of closure of the valve immediately on raising of the float by leakage water. On the other hand, the first arm of the lever is decouplable relative to the rod in such a manner that the rod movement is possible without entrainment of the lever and of the float during a closing operation of the valve triggered by, for example, attainment of a certain water level in a rinsing container of the appliance and consequent in fluencing of an air trap chamber of a level transmitter and of the pressure member. The valve can therefore be operated by a small pressure acting on the pressure member.

Embodiments of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a sectional elevation of a first safety device embodying the invention, with a float in a leakage water collecting trough and a shut-off valve fastened to a mounting of a household appliance and showing an adjustable connection between the float and valve; Fig. 2 is a sectional view, to an enlarged scale, of a first modification of the connection of a lever arm of the device to the float; Fig. 3 is a sectional view, to an enlarged scale, of a second modification of the connection of a lever arm of the device to the float; Fig. 4 is a sectional view, to an enlarged scale, of a third modification of the connection of a lever arm of the device to the float;; Fig. 5 is a sectional elevation of a second safety device embodying the invention; Fig. 6 is a sectional elevation of a third safety device embodying the invention; and Fig. 7 is a sectional elevation of a fourth safety device embodying the invention.

Referring now to the drawings, there is shown a safety device for a household appliance such as a dishwashing or laundry washing machine, the device comprising an inlet valve 41 which is, for example, switchable in dependence on program by an appliance control, a shut-off valve 1 connected in series therewith and actuable by a permanent magnet, a pressure element 2 and a float 10. The inlet valve 41 and the shut-off valve 1 form a sub-assembly with a water inlet stub pipe 42 and an outlet stub pipe 43. The valve 1, which is fastened by way of a mounting 40 to the housing of a household appliance, can be a modification of the magnetic valve of the type series 2HB distributed by Siemens AG, in which the electromagnetic system is replaced by a permanent magnet 44.A valve of that kind operates on the principle of hydraulic auxiliary relief, i.e. the pressure in the water mains supports its opening or closing operation through an equalising bore, which is freed or closed by the armature of the magnet, in the valve diaphragm (not illustrated).

The pressure element 2 has a housing 45 with a connecting stub pipe 46, which extends laterally and is connectible by way of a hose with an air chamber (not illustrated) subject to liquid pressure in the operating or rinsing container of the household appliance. Disposed within the housing 45 is the permanent magnet 44, the magnetic field of which influences an armature (not shown) of the valve 1 through a thin-walled end wall portion, adjoining the housing of the shut-off valve, of the pressure element housing. A rubber-elastic diaphragm 47 of the pressure element is interlinked with the permanent magnet. At its rim, the diaphragm is air-tightly secured by a cover 45 closing the housing 45 at its side remote from the valve. Engaging at that side of the diaphragm which is remote from the magnet is a pressure plate 3, also interlinked therewith.Extending from the pressure plate 3 is a moulded-on valve push rod 4, which passes through the cover 48 of the pressure element for coupling with the float 10.

In the embodiment of Fig. 1, a spring 11 is arranged at the rod 4, holds the first lever arm 6 against a shoulder 5 of the rod and biasses the rod in closing direction of the shut-off valve. The spring 11 is supported between the housing base 12 of the shut-off valve 1 and the first lever arm 6, which has a forked end 13 embracing the rod 4 and resting against the shoulder 5 thereof. The second lever arm 7 is connected to the discshaped float 10 by a suspension member 15 comprising an adjustable connecting portion 16 and a fastening portion 19 fastened to the float 10, for example spring tongues or the like inserted into the float body. The suspension member has an abutment 19 for limitation of the depth of insertion of the portion 19 into the float body, whilst the float 10 has a bore 23 for the reception of the spring tongues.The connecting portion 16 together with the fastening portion 19 form the member 15, for example a plastics material part, and are connected by a mounting 20 above the abutment 18. The connecting portion 16 has a toothing displaceable in fine steps relative to a receptacle 21 of the second lever arm 7. In that case, the connecting portion forms a spring clip 22, which at the outer sides of its limbs carries the finely stepped toothing 17.

The spring clip 22 is, for tolerance equalisation, clamped to a greater or lesser extent in the receptacle 21, eye or the like, of the second lever arm 7 and is secured in the clamped position by a resilient securing tag 24. According to this construction, the spring 11 at the rod 4 supports the, switching movement of the shut-off valve 1 when leakage water raises the float as well as in the normal operation on attainment of a desired water level in the operating container of the appliance, for the blocking of the water inlet.

During the assembly of the safety device, the shut-off valve 1 is fastened to the mounting 40 of the household appliance. After mounting of a leakage water collecting trough 8, a position of the lever 6, 7, which is dependent on the assembly and production tolerance, obtains between the rod 4 and the float 10 resting on the bottom of the trough 8. In order that, when leakage water collects in the trough, the float can become effective free of play against the arrow direction 9 for the closing of the shut-off valve against the rod 4 thereof, the spring clip 22 is detented so far against the receptacle 21 of the lever arm 7 that a connection exists free of play between the float, lever and valve push rod shoulder 5.

The closing of the shut-off valve, which is effected by way of the pressure element 2 from an air chamber of the operating container of the appliance and for which purpose the rod is actuated against the arrow direction 9 by the diaphragm 47, is possible without raising of the lever 7 and of the float 10, since the forked end 13 of the lever arm 6 is decouplable from the valve push rod 4 in this direction.

In the construction according to Fig. 2, the suspension of the float 10 consists of an anchor 26, which is inserted as far as an abutment 25 into the float body, and a projection 27 which penetrates the eye 21 of the second lever arm 7 and which in the installed position, with the float 10 resting on the bottom of the trough 8, is fixed by a securing ring, a lacquer coating or an adhesive substance coating 28 or the like, free of play relative to the second lever arm.

According to Fig. 3, the suspension of the float 10 consists of a spigot 29, which is detented with the second lever arm 7 and has an anchor 30, which is inserted to a greater or lesser extent into the body of the float and which in the installed position, with the float resting on the bottom of the trough 8, is fixed by a securing ring, a lacquer coating or adhesive substance coating 28 or the like, relative to the float.

Fig. 4 shows a connection of the float 10 with the lever arm 7, wherein the float has an insert 31 which forms a guide for a spigot 29 fastened to the lever arm 7. In the installed position, adjusted to be free of play, between the trough 8, float 10, lever and rod 4 or rod shoulder, the spigot 29 is fixed relative to the guide of the insert 31, for example by an adhesive substance coating 28.

In the safety device according to Fig. 5, instead of the valve push rod spring 11, a spring 14 is associated with the end of the second lever arm 7. The float 10 carries a two-part insert, the base part 32 of which is inserted from the trough 8 into the float and receives a compression spring 14. A cover part 33, which carries a spigot 35 articulatedly mounted in the second lever arm 7, is settable from the upper side of the float against the base part 32. In the installed position and with equalisation of production tolerances, the connection between the lever arm and float can be produced by a fixing 36 between the parts 32 and 33 or between the spigot 35 and the float 10.

Embodiments with other adjusting arrangements are illustrated schematically in Figs. 6 and 7. The spring 11 ensures freedom from play between the first lever arm 6 and the rod 4. The projection 27 of a fixed float anchor 26 is articulatedly fastened in the second lever arm 7. The lever 6, 7 is pushed onto a bearing axle 37, which is received by bearing blocks 38 of the housing of the valve 1. The axle 37 is mounted in vertically displaceable manner for equalisation of production tolerances. For this purpose, resilient clips 39 are moulded on or fastened to the bearing blocks 38 and notches 34 or the like are provided for the mounting of the axle.

Claims

1. A safety device for a water-conducting household appliance, comprising a shut-off valve, a valve-actuating device with a pressure member responsive to pressure to cause the valve to be shut, a float to be arranged in a leakage water collecting trough of the appliance, and a double-armed lever so connected at a first arm thereof to an actuating rod of the pressure member and at the second arm thereof to the float as to translate upward movement of the float into movement of the rod in a direction effecting operation of the pressure member for closure of the valve, the first arm of the lever being coupled to the rod to be free of play relative thereto in said direction of rod movement by the lever but to permit movement of the rod relative to the arm on response of the pressure member to pressure.

2. A device as claimed in claim 1, comprising a spring arranged at the actuating rod to hold the first lever arm against a shoulder of the rod and to bias the rod in a direction of closure of the valve.

3. A device as claimed in claim 2, wherein the first lever arm has a forked end portion engaging around the rod and resting against the shoulder thereby to couple the arm to the rod, the spring being arranged to bear against and act between the first lever arm and a housing of the valve.

4. A device as claimed in claim 1, comprising a spring arranged to act between the float and the second lever arm.

5. A device as claimed in any one of claims 1 to 3, wherein the second lever arm is connected to the float by connecting means permitting selection of the installed position of the float relative to the lever.

6. A device as claimed in claim 5, the connecting means comprising a suspension member secured to the float and provided with a finely toothed connecting portion connected to the second lever arm at a selectable part of the toothing.

7. A device as claimed in claim 6, wherein the suspension member comprises a plurality of spring tongues extending through a bore of the float to an extent determined by an abutment of the member and engaging the float to secure the member thereto, the connecting portion being in the form of an externally toothed spring clip resiliently clamped in a selected position in an eye of the second lever arm and locked in the selected position by a locking element.

8. A device as claimed in claim 5, the connecting means comprising a suspension member mounted in a defined position in the float and provided with a projection which extends through an eye of the second lever arm and is fixed in a selected position therein by fixing means.

9. A device as claimed in claim 5, the connecting means comprising a suspension member having a spigot secured to the second lever arm and an insert portion which extends in a recess in the float and is fixed in a selected position therein by fixing means.

10. A device as claimed in claim 5, the connecting means comprising a suspension member having an insert portion mounted in a defined position in the float and a spigot which is secured to the second lever arm and fixed in a selected position to the insert portion by fixing means.

11. A device as claimed in claim 4, wherein the second lever arm is connected to the float by connecting means comprising a base member which is inserted into the float from a base side thereof and receives the spring, and a cover member which has a spigot secured to the second lever arm and which is arranged on the base member at an upper side of the float to be acted on by the spring, the cover member being fixed in a selected position relative to the float or the base member by fixing means.

12. A device as claimed in claim 2, wherein the lever is so mounted at its fulcrum to a housing of the valve that its pivot axis is adjustable in height position.

13. A device as claimed in claim 12, wherein the lever is provided at its fulcrum with an axle mounted in a selectable one of a plurality of detents in a resilient mounting clip at the housing.

14. A device substantially as hereinbefore described with reference to Figure 1 of the accompanying drawings.

15. A device as claimed in claim 14 and modified substantially as hereinbefore described with reference to any one of Figs. 2 to 4 of the accompanying drawings.

16. A device substantially as hereinbefore described with reference to Fig. 5 of the accompanying drawings.

17. A device substantially as hereinbefore described with reference to Fig. 6 of the accompanying drawings.

18. A device substantially as hereinbefore described with reference to Fig. 7 of the accompanying drawings.