EP0863243A2 - Leakage or overflow detecting device for a washing machine - Google Patents

Abstract

System to detect a leak or overflow, in a domestic clothes washing machine, comprises a housing (18) with a lateral opening (23) for liquid to enter in the event of a leak or overflow. It contains at least one body or substance as a pastille (24, 25) that reacts with the liquid to form a gas. The housing cover (22) has an opening (37) for the gas to escape to be registered by a gas detector. Preferably the pastilles (24, 25) are bicarbonate of soda, and sodium pyrophosphate or sodium dihydrogen phosphate. The pastilles produce 300 cm<3> of CO2. Alternatively the pastilles are ammonium dihydrogen phosphate and a metasilicate of sodium pentahydrate to form crystals of Na2SiO35H2O. The pastilles produce 300 cm<3> of ammonia gas.

Description

The present invention relates to a device for leak or overflow or other detection liquid, for a washing machine or washing up. This leak or leak detection device overflow is itself part of a security system, whose role is to limit the damage caused by leaks or overflows of water, when closing the water supply to the machine concerned, in the event of detection of a leak or overflow. More in particular, the proposed device can be integrated in a security system capable of intervening also good in case of fault on the water supply pipe of the washing machine, only in the event of a leak or overflow inside this washing machine.

In the French patent application N ° 9011046/2666135 in the name of the Applicant, to which corresponds to the European patent application N ° 91420302.1 / 0474569, a device is described overflow safety device for washing machine or the dishes. As shown in Figure 1 of the drawing diagram attached, this known safety device 1 is placed at the hydraulic connection 2 of the hose 3 supplying water to the washing machine 4. Referring also in the more detailed sectional view of FIG. 2, the flexible 3 includes inner pipe 5 normally traversed by the water brought to the machine 4, and a sheath waterproof exterior 6. The safety device 1 comprises a mechanical sensor, which reacts to the pressure of everything liquid reaching the annular space 7 located between the pipe 5 and the sheath 6, such a presence of liquid being considered an undesirable leak. When he is actuated, the mechanical sensor controls an internal valve to safety device 1, which interrupts the flow water to hose 3, and therefore to the washing machine 4.

More specifically, as shown in the figure 2, the safety device 1 has a passage 8, which connects the annular space 7, located between the pipe 5 and the sheath 6, to an annular chamber 9 in which is mounted, axially movable, an annular piston 10. The pressure resulting from water leakage from hose 5 is also transmitted in room 9, and causes a displacement axial of the annular piston 10, against which this pressure. The movement of the piston 10 releases a pin 11 which, moved by a spring 12, releases itself a rod movable axial 13, which carries a shutter 14 pushed by a other spring 15. This action closes the valve internal to safety device 1, located upstream of the hose 3 and washing machine 4. Details complementary to this safety device 1 can be found in the description of the patent application French N ° 9011046/2666135. One of the advantages of this device is that the gasket 16, crossed by the pin 11, is "self-protected" in case of leakage, that is to say in the event of a leakage created by this attached, the safety device 1 will also close the passage of water to hose 3 and the machine wash 4.

Despite its advantages, the safety device here mentioned has the disadvantage or insufficiency of being effective only in the event of a hose leak 3, but not to react to leaks or overflows producing inside the washing machine 4.

The present invention aims to eliminate this disadvantage, by providing a device for detecting leak or overflow, which can be used efficiently anywhere and especially for detect a leak or an overflow of water inside of the washing machine, the proposed device can be associated with the previously known security device mentioned, or be used independently of it.

To this end, the subject of the invention is a leak or overflow detection device for washing machine, which consists essentially of a case provided with at least one opening allowing the entry of a liquid following a leak or overflow, and containing at least one body or one substance which, in contact with the liquid to be detected penetrating in the housing through the aforementioned opening, is suitable for produce a gas, the housing still having an orifice for the escape of gas to a means of detecting this gas.

Thus, the invention provides a device for simple, light leak or overflow detection and compact, and which is independent of any source of energy, any spring and any other system of mechanical trigger, which may be dangerous or ineffective, if blocked or corroded over time, whether used or not. In addition, the device object of the invention can be installed in any location where leaks or overflows of water or other liquid may occur, or be collected. So this detection device can be especially placed towards the bottom of a washing machine. The principle of gas evolution, specific to the the invention also makes it possible to detect this gas by any appropriate means, directly associated with the housing or, contrary, located at a distance from the box to which it can be connected by any suitable conduit. Gas detection, significant of a leak or an overflow, can itself trigger an alarm and / or activate a means of setting in safety, in particular by closing a valve which cuts the water supply to the washing machine. In what concerns the body or substance capable of producing gas, suitable chemicals are chosen to react to the presence of water, while remaining insensitive to ambient humidity.

In a particular embodiment, the detection device includes a form box cylindrical or prismatic, the side wall of which includes the opening for the entry of the liquid to be detected, the bottom of which is provided with means for positioning at least one pellet of a substance capable of producing a gas in contact with the liquid to be detected, and the face of which or the cover has the opening exhaust gas. This hole is presented advantageously as a fitting or a chimney, on which can be connected the conduit leading by means of gas detection, located at a distance from the housing.

According to a first possibility, the case is designed to contain a single tablet, of a substance able, by itself, to react to the liquid to be detected, releasing a gas.

According to another possibility, the housing is provided to contain two lozenges, in substances different, such as an acid and a base, capable of react and produce a gas only if both are simultaneously immersed in the liquid to be detected. This avoids the risk of a single pellet producing gas or be damaged in the presence of moisture, which inadvertently trigger the security system, or would make it inoperative. Of course, this mode of advantageous achievement assumes that neither alone cannot produce gas by presence of moisture, but that, on the other hand, one of the pellets produce gas in the presence of particles of the other pellet transported by water entering the housing through the side opening.

The means of positioning the patch single, or both, as the case may be, are formed by parts such as legs making protrusion on the bottom of the case, inside this latest ; in particular, for a shaped tablet general circular, two opposite legs with profile curved are appropriate.

In order to maintain the gas pressure created at inside the case, and to be able to use it as means of detecting leaks or overflows, the device is preferably designed in such a way that the lateral inlet opening of the liquid to be detected either automatically closed, quickly enough, after initiation of the gas producing reaction.

For this purpose, the case still contains a lever, subjected to the action of a spring and mounted so as to pivot so that part of this lever is able to close the inlet opening of the liquid to be detected, the lever comprising a spout capable of being initially retained by hanging in a notch formed at the periphery of the single tablet or one of the tablets, so that keep the shutter part of this lever away from the aforementioned opening, the reduction in size and / or solidity of the tablet in contact with the liquid to be detected causing the release of the lever spout, and, under the effect of the spring, the application of the obturating part of this lever on the aforementioned opening. Such a mechanism requires the use of a configuration pad particular, and the correct orientation of this patch inside the case; for this purpose, the tablet concerned still has, at its periphery, at least one notch cooperating with a complementary boss formed on a positioning part or tab projecting from the bottom of the case.

The gas produced in the event of liquid penetration in the housing, can itself be detected chemically, physically or mechanically, depending on the means of detection considered. In an advantageous embodiment, the detection device object of the invention is combined with the known security device, previously described and illustrated in Figures 1 and 2, which allows you to do the economy of a special detection means for gas, and to realize a global security system. For this purpose, the gas exhaust port, belonging to the housing of the device object of the invention, is connected by a leads to the annular space between the pipe inner and outer sheath of the hose. So a gas evolution in the box created in this space annular pressure similar to that resulting from a water entering the same annular space, and causing also the triggering of the safety device. For a reliable operation, a non-return valve is inserted on the conduit connecting the housing to the hose.

Figure 3 est une vue d'ensemble très schématique d'une machine à laver le linge, équipée du dispositif de détection de fuite ou de débordement objet de l'invention ;

Figure 4 est une vue en perspective éclatée du boítier de ce dispositif de détection ;

Figure 5 est une vue en coupe horizontale de ce boítier.

The invention will in any case be better understood with the aid of the description which follows, with reference to the appended diagrammatic drawing representing, by way of example, an embodiment of this leak detection or overflow detection device for a machine to wash :

Figure 3 is a very schematic overview of a washing machine, equipped with the leak detection or overflow device object of the invention;

Figure 4 is an exploded perspective view of the housing of this detection device;

Figure 5 is a horizontal sectional view of this housing.

FIG. 3 shows a washing machine 4, supplied with water by a hose 3 from which is placed a known safety device 1, as shown in detail in Figure 2 commented above. The device leak detection or overflow object of the invention, designated as a whole by the reference 17, completes safety device 1, and combines with this one, to detect leaks and overflows to inside the washing machine 4.

This leak or leak detection device overflow 17 mainly comprises a housing 18, placed in the lower part of the washing machine 4, on the bottom 19 thereof. The case 18, and its elements internal, are shown in detail in Figures 4 and 5.

Generally cylindrical, the housing 18 has a bottom 20, a side wall 21 of relatively low height, and a removable cover 22. In the wall side 21 is formed an opening 23, allowing entry of water or other liquid to be detected.

The housing 18 is designed to receive two pads 24 and 25, of generally circular shape, positioned on its bottom 20, at a distance from each other, these two lozenges being in different substances chosen to cause a chemical reaction with gas release, only when submerged simultaneously in water. In particular, the first tablet 24 is in a basic substance, and the second tablet 25 is in an acidic substance, more examples specific given below.

For positioning and holding the second patch 25, the bottom 20 of the housing 18 has two tabs 26 and 27 projecting, opposite to each other and each having a curved profile.

The first patch 24 has, at its periphery, a hooking notch 28 and a notch 29, diametrically opposites. For the positioning of this patch 24, the bottom 20 of the housing 18 has a projecting part rounded 30, internally provided with a boss 31 complementary to the notch 29. The patch 24 is thus angularly positioned, so that its notch 28 is not covered by part 30.

Inside the housing 18 is pivotally mounted, around an axis 32 perpendicular to the bottom 20, a lever 33, one end of which has a sealing pallet 34, located next to the entrance opening 23. The other end of lever 33 is subjected to the action of a spring 35, pressing against the side wall 21 of the housing 18, and biasing the lever 33 in the direction of the application of the pallet 34 against the edge of opening 23.

At its end provided with the shutter pallet 34, the lever 33 also has a spout 36, directed towards the location of the first patch 24, when this tablet 24 is in place, spout 36 is hooked in the notch 28 of said pad 24, as shown on the Figure 5; the lever 33 is thus retained in a position such that the shutter blade 34 remains at a distance from opening 23, the spring 35 being compressed at maximum.

Finally, referring again to Figures 3 and 4, the cover 22 of the housing 18 is provided in its center of a gas exhaust port 37, made under the shape of a fitting or chimney on which is connected the outlet of a conduit 38, leading to a means of remote gas detection. In the example considered, the duct 38 is directed towards the outside, and it is connected to hose 3, more particularly to the annular space 7 located between the inner pipe 5 and the outer sheath 6 of this hose 3 (see also the Figure 2, left). A non-return valve 39 is interposed on the conduit 38, at any point located between the housing 18 and the connection to the hose 3.

The operation of the detection device 17, previously described, is as follows:

In the event of a leak or overflow to inside the washing machine 4, the released water falls on the bottom 19 of the machine 4 and, through the opening 23 normally kept open, it penetrates inside of the housing 18. This water then comes simultaneously to the contact of the two pads 24 and 25, and a clearance gaseous begins to occur. Immediately, under the effect of the chemical reaction has started, the first tablet 24 sees its diameter and / or its solidity decrease, so that the spout 36 is released; the lever 33 is therefore released, and under the effect of spring 35, this lever 33 is pivoted slightly around the axis 32, so that the pallet 34 comes close the opening 23, also preventing gas leaks outwards from the housing 18 through this opening 23.

The gas released therefore escapes from the housing 18 to through the hole 37 of the cover 22, and it traverses the conduit 38 to reach the annular space 7 of the flexible 3, by crossing the valve 39. Arriving in space 7, the gas there creates an increasing pressure which move the annular piston 10 (see figure 2) and trigger safety device 1, causing the cut off the water flow to the washing machine 4, and possibly also activating a signaling visual, in the same way as if pressurized water had entered space 7 following a leak at hose level 3.

To reset the detection device 17, after detection of leak or overflow and suppression of this defect, it is advisable to open the case 18 in removing its cover 22 and then introducing two new pads 24 and 25 by positioning them suitably, the tablet 24 must in particular be correctly oriented by means of its notch 29. The lever 33 must also be reset, by inserting its beak 36 in the notch 28 of the patch 24, so as to release opening 23.

As regards the constituent substances of the two tablets 24 and 25, the first tablet 24 is for example made up of 0.7 g of sodium bicarbonate or other bicarbonate, while the second tablet 25 is made up of 3 g of sodium pyrophosphate (or sodium dihydrogen phosphate); this produces approximately 300 cm ³ of carbon dioxide (CO ₂ ). According to another example, the first tablet 24 consists of 1 g of ammonium dihydrogen phosphate, while the second tablet 25 consists of 2 g of sodium metasilicate pentahydrate in the form of crystals (Na ₂ SiO ₃ 5H ₂ O), which produces about 300 cm ³ of gaseous ammonia.

None of the pastilles of these compositions can, alone, generate gas in the presence of humidity, and only a mixture, resulting from a flow of a pellet 24 to the other tablet 25 in the presence of water, can produce a gas, which prevents any untimely triggering of the security system.

Other substances can be chosen for pads 24 and 25, but in all cases the gas produced in the presence of water should be non-toxic and not flammable, for obvious safety reasons.

• par des modifications purement constructives, concernant par exemple le boítier ;
• par l'utilisation d'une seule pastille, réagissant directement au contact de l'eau pour produire un gaz ;
• par le recours à tout moyen de détection du gaz produit, en particulier un moyen indépendant du dispositif de sécurité associé au flexible d'amenée d'eau vers la machine ;
• par l'application du dispositif de détection, objet de l'invention, non pas à une machine à laver le linge, mais à une machine à laver la vaisselle.

As is obvious, and as it follows from the above, the invention is not limited to the only embodiment of this leak detection or overflow detection device for a washing machine which has been described above. , for exemple ; on the contrary, it embraces all of the variant embodiments and applications respecting the same principle. In particular, we would not depart from the scope of the invention:

• by purely constructive modifications, concerning for example the case;
• by the use of a single tablet, reacting directly on contact with water to produce a gas;
• by using any means of detecting the gas produced, in particular a means independent of the safety device associated with the hose for bringing water to the machine;
• by applying the detection device, object of the invention, not to a washing machine, but to a dishwashing machine.

Claims (10)

Leak or leak detection device overflow of water or other liquid, for a machine washing clothes or dishes, characterized in that consists essentially of a housing (18) provided at least one opening (23) allowing entry of a liquid as a result of a leak or overflow, and containing at least one body or substance (24, 25) which, in contact with the liquid to be detected entering the housing (18) through the aforementioned opening (23), is suitable for produce a gas, the housing (18) further comprising a orifice (37) for the escape of gas to a means of detection (1) of this gas. Leak detection or overflow according to claim 1, characterized in that it comprises a housing (18) of cylindrical shape or prismatic, the side wall (21) of which has the opening (23) for the entry of the liquid to be detected, of which the bottom (20) is provided with means (26, 27, 30, 31) for the positioning of at least one patch (24, 25) in one substance capable of producing a gas on contact with the liquid detect, and whose upper face or cover (22) includes the gas exhaust port (37). Leak or leak detection device overflow according to claim 2, characterized in that the exhaust port (37) of the gas appears as a fitting or chimney, to which is connected a conduit (38) leading to the detection means (1) of this gas, located at a distance from the housing (18). Leak or leak detection device overflow according to claim 2 or 3, characterized in what the housing (18) is designed to contain a single lozenge, into a substance capable, by itself, of reacting to the liquid to be detected, releasing a gas. Leak or leak detection device overflow according to claim 2 or 3, characterized in what the housing (18) is designed to contain two tablets (24, 25), made of different substances, such as that an acid and a base, capable of reacting and producing a gas only if both are submerged simultaneously in the liquid to be detected. Leak or leak detection device overflow according to claim 4 or 5, characterized in what the means for positioning the single pellet, or two tablets (24, 25) as the case may be, are made up of parts such as legs (26, 27, 30), projecting from the bottom (20) of the housing (18), inside the latter, in particular by two opposite legs (26, 27) with curved profile, suitable for a tablet (25) of circular shape. Leak or leak detection device overflow according to any one of claims 2 6, characterized in that the housing (18) contains a lever (33), subjected to the action of a spring (35) and mounted pivoting (axis 32) so that part (34) of it lever (33) is able to close the inlet opening (23) liquid to be detected, the lever (33) comprising a spout (36) suitable for being initially retained by hanging in a notch (28) formed at the periphery of the single patch or one of the pastilles (24, 25), so as to maintain the shutter part (34) of this lever (33) at a distance from the aforementioned opening (23), the reduction in size and / or strength of the tablet (24) in contact with the liquid to detect causing release of the lever spout (36) (33) and, under the effect of the spring (35), the application of the obturating part (34) of this lever (33) on the opening cited above (23). Leak or leak detection device overflow according to all of claims 6 and 7, characterized in that the pad (24) provided with the notch (28) still has, at its periphery, at least one notch cooperating with a complementary boss (31) formed on a positioning part or tab (30), projecting from the bottom (20) of the housing (18). Leak or leak detection device overflow according to any one of claims 1 to 8, characterized in that it is combined with a device overflow safety device (1) placed at the connection hydraulic (2) of the hose (3) for supplying water to the washing machine (4) concerned, the hose (3) comprising an inner pipe (5) and a waterproof sheath exterior (6), the safety device comprising a mechanical sensor which reacts to the pressure of a liquid reaching the annular space (7) located between the pipe (5) and the sheath (6), and the exhaust port (37) of the gas, belonging to the housing (18) of the detection device leak or overflow (17), being connected by a conduit (38) to the annular space (7) located between the pipe inside (5) and the outer sheath (6) of the hose (3), so that a release of gas in the housing (18) creates in this annular space (7) a pressure analogous to that resulting from water entering the same annular space (7), and also triggers the safety device (1). Leak or leak detection device overflow according to all of claims 3 and 9, characterized in that a non-return valve (39) is interposed on the conduit (38) connecting the housing (18) to flexible (3).

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