Automatic shut-off device

The present invention relates generally to the field of automat- ic shut-off devices. More specifically, the present invention is related to a shut-off device for filling vessels with a liquid.

BACKGROUND OF THE INVENTION Automatic shut-off devices for filling vessels with a liquid, specifically water, are known in prior art. Specifically, shut- off devices are known which use the principle of buoyancy for stopping the provision of liquid. For example, a floating entity with a density lower than the density of water swims on the wa- ter surface thereby detecting the water level. Based on the po ^¬ sition of the floating entity, a liquid valve is controlled which enables/disables the water flow. Mostly, the flow rate of shut-off devices using the principle of buoyancy depends on the water level, i.e. in case of low water level, the flow rate is high and decreases with rising water level. So, in case of a liquid level close to the desired maximum filling level, the flow rate is very low which significantly increases the filling duration . In addition, known shut-off devices have to be mounted to the vessel wall. However, such mounting is not possible in case of flexible, air-filled walls, e.g. the wall of an inflatable pool.

SUMMARY OF THE INVENTION

It is an objective of the embodiments of the present invention to provide an automatic shut-off device which does not show a steadily decreasing flow rate with increasing filling level and can be flexibly used without a solid mounting at the vessel wall. The objective is solved by the features of the independent claim. Preferred embodiments are given in the dependent claims. If not explicitly indicated otherwise, embodiments of the inven ^¬ tion can be freely combined with each other.

According to an aspect, the invention relates to an automatic shut-off device for filling a container with a liquid. The shut- off device comprises:

- a housing including a valve for enabling a liquid flow

through a liquid path provided within the housing;

- a control element for opening the valve in order to enable a liquid flow through the liquid path; and

- a closing mechanism for automatically closing the valve de ^¬ pendent on the liquid level within the container.

The closing mechanism comprises a deflector portion arranged within the housing for receiving a liquid jet, said deflector portion being coupled with a lever, said lever being operatively coupled with the valve. The shut-off device further comprises liquid jet variation means configured to vary the force of the liquid jet applied to the deflector portion depending on the liquid level within the container. The lever is configured to control the valve based on the force of the liquid jet applied to the deflector portion. Said automatic shut-off device is advantageous because the clos ^¬ ing mechanism is included in the housing of the shut-off device and no floating entity is used for measuring the liquid level but the force applied by the liquid jet to the deflector portion is varied depending on the liquid level. Thereby, the effort for installing the floating entity is avoided.

According to embodiments, the lever is adapted to keep the valve in an open position if the force applied to the deflector por ^¬ tion is above a certain threshold. Said threshold may be defined by the force of a spring coupled with the valve. So, if the force caused by the liquid jet at the deflector portion and for ^¬ warded by the lever exceeds the spring force, the valve remains in the open position. Otherwise, the valve closes because of the spring force acting on the valve.

According to embodiments, the valve is spring-loaded, the spring being preloaded to push a valve portion in the closed position. So, the spring force and the force transferred by the lever be ^¬ cause of the liquid jet applied to the deflector portion are di ^¬ rected in opposite directions. Thereby, an automatic closing is possible if the force provided by the lever drops below the spring force.

According to embodiments, the lever is coupled with the valve via a tappet. Said tappet may protrude from a side portion of the shut-off device into the interior of the housing in which the valve is located. Said tappet may be coupled with a valve portion, e.g. a valve plunger, a valve body or a membrane (mem ^¬ brane valve) in order to open/close the valve.

According to embodiments, the lever is pivotally coupled with the housing. So, the lever can be swivelled in a first position in which the valve is open and in a second position, in which the valve is closed. The swivelling of the lever may be per- formed around a pivot axis which is arranged perpendicular or essentially perpendicular to the flow direction of the liquid through the shut-off device. Thereby, the force applied to the deflector portion can be transferred upstream to a location at which the valve is located.

According to embodiments, a nozzle is provided within the liquid path in flow direction upstream the deflector portion. The noz ^¬ zle may be adapted to provide a focussed liquid jet which is ap ^¬ plied downstream to the deflector portion. Said focussing may be obtained by a nozzle with a tapered nozzle channel, i.e. the width or diameter of the nozzle channel decreases towards the nozzle outlet. Thereby a high-power liquid jet is provided to the deflector portion. According to embodiments, the nozzle comprises one or more rips extending into the nozzle channel. The ribs may be longitudinal ribs extending along the whole or essentially the whole length of the nozzle. Thereby, the focusing of the jet can be improved.

According to embodiments, a channel portion is provided down ^¬ stream the nozzle, the channel portion comprising a width or di ^¬ ameter greater than the width or diameter of the nozzle channel. Said channel portion forms part of the liquid jet variation means. Due to the greater width or diameter, mixing of

air/liquid can be achieved within said channel portion.

According to embodiments, the channel portion forms a mixing chamber for adding air or liquid to the liquid jet through an inner injection opening provided within the wall of the mixing chamber. Preferably, the opening may be provided close, specifi ^¬ cally in direct proximity to the nozzle. Said opening may pro ^¬ vide a feed opening through which air or liquid can be fed in in radial direction (radial with respect to the flow direction of the liquid jet through the channel portion) .

Preferably, the length of the channel portion may be greater than the length of the nozzle channel. Thereby, the mixing of air/liquid with the liquid jet can be improved. According to embodiments, an intermediate chamber or channel is provided between the channel portion and an outer housing wall. The medium to be mixed with the liquid jet is sucked through said intermediate chamber into the channel portion. Thereby it is possible to create a distance between an opening in the hous- ing wall (through which the medium is sucked into the housing from the surrounding environment) and the inner injection open ^¬ ing .

According to embodiments, an outer injection opening is provided at the outer housing wall, said outer injection opening being fluidly coupled with the inner injection opening via said inter ^¬ mediate chamber or channel. Said outer injection opening may be arranged at a distance (measured along the flow direction of the liquid jet) to the inner injection opening. For example, the in- ner injection opening may be arranged close to the nozzle per ^¬ forming the forming of the liquid jet and the outer injection opening may be arranged close to a jet forming portion, i.e. at the opposite end of the channel portion.

Through said outer injection opening, depending on the liquid level within the vessel to be filled, air or liquid is sucked in. The sucked-in air does not lower the force of the liquid jet applied to the deflector portion such that the valve is closed. However, in case that the liquid level rises such that the outer injection opening is covered by liquid, liquid is sucked in, said sucked-in liquid lowering the force of the liquid jet. As a result, the valve closes automatically.

According to embodiments, liquid retarding means or pressure re ^¬ duction means are provided within the housing. Said liquid re ^¬ tarding means/pressure reduction means may be adapted to retard a strong water flow caused by a high liquid pressure by generat ^¬ ing turbulences within the liquid flow. Thereby it can be avoid ^¬ ed that in case of high liquid pressure the liquid jet variation means can not lower the force of the liquid jet such that the valve closes when liquid is sucked into the mixing chamber.

According to embodiments, said liquid retarding means or pres ^¬ sure reduction means are formed by a grid comprising multiple elongated holes. According to other embodiments, the liquid re- tarding means or pressure reduction means may be any means adapted to limit the liquid pressure provided to the nozzle, re ^¬ spectively, to the deflector portion. According to embodiments, the shut-off device comprises a jet forming portion downstream the deflector portion, said jet form ^¬ ing portion being adapted to collect the liquid deflected by the deflector portion. For example, the jet forming portion may be double-hopper shaped, i.e. the liquid deflected by the deflector portion is on the one hand collected and on the other hand guid ^¬ ed to a liquid dispensing opening provided at the jet forming portion. For example, the jet forming portion may comprise a concave interior surface along which the liquid is guided to ^¬ wards the liquid dispensing opening.

According to embodiments, the shut-off device comprises a quick connector portion in order to couple the shut-off device with a water hose. Thereby it is possible to couple the shut-off device with the free end of a water hose. In order to fill a certain vessel, the shut-off device coupled with the water hose is in ^¬ serted into the vessel. In case that the liquid level reaches the outer injection opening, the filling process is automatical ^¬ ly stopped. The term "vessel" according to the present disclosure refers to any container which can be filled with liquid, specifically wa ^¬ ter cans, buckets, pools etc.

The term "essentially" or "approximately" as used in the inven- tion means deviations from the exact value by +/- 10%, prefera ^¬ bly by +/- 5% and/or deviations in the form of changes that are insignificant for the function. BRIEF DESCRIPTION OF THE DRAWINGS

The various aspects of the invention, including its particular features and advantages, will be readily understood from the following detailed description and the accompanying drawings, in which :

Fig. 1 illustrates an embodiment of an automatic shut-off de ^¬ vice in a perspective view;

Fig. 2 illustrates the automatic shut-off device of Fig. 1 in a side view;

Fig. 3 illustrates the automatic shut-off device of Fig. 1 in a first sectional view in a cutting plane parallel to the flow direction of the liquid; and

Fig. 4 illustrates the automatic shut-off device of Fig. 1 in a second sectional view in a cutting plane parallel to the cutting plane of Fig. 3.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The present invention will now be described more fully with ref ^¬ erence to the accompanying drawings, in which example embodi ^¬ ments are shown. However, this invention should not be construed as limited to the embodiments set forth herein. Throughout the following description similar reference numerals have been used to denote similar elements, parts, items or features, when ap ^¬ plicable .

Fig. 1 and 2 illustrate an embodiment of an automatic shut-off device 1. The automatic shut-off device 1 according to the pre- sent embodiment is adapted to be coupled with a water hose. So, for filling a vessel, e.g. a watering can, a bucket or a pool with liquid, specifically with water, the automatic shut-off de ^¬ vice 1 is coupled with the free end of the water hose and said automatic shut-off device 1 is put into the vessel. For example, the automatic shut-off device 1 comprises a quick connector por ^¬ tion 2.2 for coupling the automatic shut-off device 1 with the water hose, specifically, with a quick connector arranged at the water hose.

The automatic shut-off device 1 comprises a housing 2, in which a liquid path 4 is provided. Said liquid path 4 extends from a liquid input, for example, provided at the quick connector por ^¬ tion 2.2 to a liquid dispensing opening 2.3. The liquid dispens ^¬ ing opening 2.3 may be provided opposite to the quick connector portion 2.2.

In order to control the provision of liquid by means of the au ^¬ tomatic shut-off device 1, a valve 3 is provided within the housing 2. The valve 3 is adapted to control the liquid flow through the liquid path 4. At the housing 2, a control element 5 is provided for controlling a valve element, e.g. a valve body in order to enable a liquid flow through the liquid path 4 and thereby the provision of liquid at the liquid dispensing opening 2.3. For example, the valve 3 may be a membrane valve comprising a membrane for opening/closing the liquid path through the valve 3. The control element 5 may be, for example, a control switch, control button etc.

In order to automatically close the valve 3 when the liquid within the vessel reaches a certain liquid level, the automatic shut-off device 1 comprises a closing mechanism 6. For example, the closing mechanism 6 may work according to the scales princi ^¬ ple. In other words, the state of the valve (e.g. open or closed) depends on a comparison of different forces, namely a first force caused by the liquid jet and a second force counter- acting said first force. Thereby, no floating body is necessary which controls the valve 3.

In the following, the working principle of the automatic shut- off device 1 is explained in closer detail based on the features shown in Fig. 3 and 4. In Fig. 4, the liquid path 4 through the automatic shut-off device 1 is shown based on the dotted line. The liquid is received at the quick connector portion 2.2 and provided through a liquid channel to the valve 3. In case that the valve is in an open position (effected by a respective input at the control element), the liquid is guided to a nozzle 8. Said nozzle 8 may be configured to provide a focussed liquid jet at its output. For example, the nozzle 8 may have a nozzle chan ^¬ nel with a width wl or diameter smaller than the liquid channel upstream said nozzle 8. More in detail, the nozzle 8 may com ^¬ prise a tapered nozzle channel, i.e. the width wl or diameter of the nozzle orifice decreases in flow direction FD . The nozzle 8 may comprise multiple ribs 8.1 or bars extending into the nozzle channel. The ribs 8.1 may be longitudinal ribs comprising a lon- gitudinal side extending parallel or essentially parallel to the flow direction FD of the liquid. According to other embodiments, the ribs 8.1 may be twisted in order to provide a spiral liquid guide . Downstream the nozzle 8, specifically directly behind the nozzle 8, a channel portion 9 is provided which comprises a width w2 greater than the width wl of the nozzle channel. More in detail, there may be an abrupt, step-like increase of the width of the liquid channel from the nozzle 8 to the channel portion 9. For example, the channel portion 9 may be a tubular-shaped liquid path portion which may be formed by a wall 9.1 comprising a cir ^¬ cular or essentially circular cross section. Said channel por ^¬ tion 9 may be arranged centred with respect to the nozzle chan ^¬ nel. The length L of the channel portion 9 (measured along the flow direction) is greater than the length 1 of the nozzle 8. The channel portion 9 may form a mixing chamber in which air or liquid is mixed into the liquid jet provided by the nozzle 8 de ^¬ pending on the liquid level within the vessel. The working prin- ciple of said mixing chamber is described below in greater de ^¬ tail .

Downstream the nozzle 8, respectively, the channel portion 9, a deflector portion 6.1 is provided. The deflector portion 6.1 may comprise a plate-like shape. The surface of the deflector por ^¬ tion 6.1 may be arranged such that the liquid jet provided by the nozzle 8 through the channel portion 9 impinges vertically or essentially vertically at the deflector portion 6.1. The de ^¬ flector portion 6.1 may comprise a diameter greater than the width wl of the nozzle channel. Specifically, the diameter of the deflector portion 6.1 may be chosen equal or essentially equal to the width w2 of the channel portion 9.

After leaving the channel portion 9, the liquid jet hits the de- flector portion 6.1. Thereby, the liquid jet is laterally de ^¬ flected. More in detail, the liquid jet is splashed onto the de ^¬ flector portion 6.1 thereby applying a force onto the deflector portion 6.1. Said force is applied in a direction parallel to the flow direction FD of the liquid jet provided by the nozzle 8.

After splashing onto the deflector portion 6.1, the laterally deflected liquid jet is received by a jet forming portion 12. Said jet forming portion 12 may comprise a curved shape. More in detail, the jet forming portion 12 may comprise a double-hopper ^¬ like shape. Thereby, on the one hand, the radially deflected liquid is collected and, on the other hand, guided to the liquid dispensing opening 2.3 in a focussed way. The closing mechanism 6 comprises means for comparing the force applied to the deflector portion 6.1 which is used to keep the valve 3 open with a force working in the opposite direction, i.e. trying to close the valve 3. For example, the valve 3 may be spring-loaded, i.e. a force applied by a spring 6.3 acts on a valve element in order to close the valve 3 thereby stopping the liquid jet. In order to be able to compare the force applied to the deflector portion 6.1 and the force applied by the spring 6.3 on the valve element, the closing mechanism 6 comprises a lever 6.2. Said lever 6.2 may be movably mounted within the housing 2. More in detail, said lever 6.2 may be pivotally mounted within the housing 2. The lever 6.2 may comprise two lever arms 6.2.1, 6.2.2 which are coupled in the area of a pivot axis A of said lever 6.2. Said pivot axis A may be arranged in an area between the valve 3 and the deflector portion 6.1 and may be orientated perpendicular or essentially perpendicular to the flow direction FD of the liquid. A first free end of the lever 6.2 (second lever arm 6.2.2) may be coupled with the de ^¬ flector portion 6.1. The second free end of the lever 6.2 (first lever arm 6.2.1) may be operatively coupled with the valve 3.

Said lever 6.2 may comprise a longitudinal shape and may extend with its longitudinal axis along the longitudinal axis of the automatic shut-off device 1. The coupling of the lever 6.2 with the valve 3 is obtained by a tappet 6.4. Said tappet 6.4 may be a pin-shaped coupling mean which is movably, specifically slidably mounted within the hous ^¬ ing 2. Said tappet 6.4 may be arranged transversely to the flow direction FD . By means of said tappet 6.4, the first lever arm 6.2.1 opposite to the deflector portion 6.1 is coupled with the valve element thereby being able to open/close the valve 3.

Referring to fig. 3 and 4, in the following, the variation of the force applied by the liquid jet to the deflector portion 6.1 is described in closer detail. The automatic shut-off device 1 comprises variation means 7 for varying the force applied by the liquid jet to the deflector portion 6.1 depending on the liquid level within the vessel. The wall 9.1 of the channel portion 9 comprises one or more injec ^¬ tion openings 7.1, in the following referred to as inner injec ^¬ tion opening. Said inner injection opening 7.1 may be arranged in close proximity to the nozzle 8, i.e. immediately downstream the nozzle 8. The inner injection opening 7.1 may provide an opening in the wall 9.1 of the channel portion 9 in a radial di ^¬ rection with respect to the flow direction (lateral opening) .

Between the wall 9.1 and an outer housing wall 2.1, an interme ^¬ diate chamber 10 is provided. In the outer housing wall 2.1, an outer injection opening 7.2 is provided. Said outer injection opening 7.2 is arranged at a distance to the inner injection opening 7.1, said distance being measured along the flow direc ^¬ tion FD . For example, the inner injection opening 7.1 may be ar ^¬ ranged close to the nozzle 8 and the outer injection opening 7.2 may be arranged close to the jet forming portion 12.

As shown by the dotted line in Fig. 3, a medium can be sucked in through the outer injection opening 7.2, the intermediate cham ^¬ ber 10 and the inner injection opening 7.1. Said suction power is caused by the liquid jet provided through the channel portion 9.

First, the situation is considered that the housing 2 is not im- merged in the liquid received within the vessel. In that case, the outer injection opening 7.2 is not covered by liquid. As such, air is sucked into the intermediate chamber 10 and provid ^¬ ed through the inner injection opening 7.1 into the channel por ^¬ tion 9. The air is mixed with the liquid jet. However, the force applied by the liquid jet mixed with the sucked-in air holds the valve 3 in the open position. So, in other words, the force pro- video! by the lever 6.2 to the tappet 6.4 (caused by the liquid jet at the deflector portion 6.1) exceeds the spring force.

Therefore, the valve remains open and the liquid level within the vessel is rising.

When the liquid level reaches the outer injection opening 7.2, instead of air, liquid is sucked in. Said liquid is provided through the inner injection opening 7.1 into the channel portion 9. Thereby, the liquid jet provided by the nozzle 8 is disturbed by the sucked-in liquid. Said disturbance causes a reduction of the force of the liquid jet provided to the deflector portion 6.1. As a result, the force of the spring 6.3 applied to the valve 3 exceeds the force applied by the lever 6.2 to the valve 3. Thereby, the valve 3 is closed and the provision of liquid into the vessel is automatically stopped. So, after manually opening the valve 3 by operating the control element 5 (as indi ^¬ cated by the arrow in Fig. 3), the valve 3 remains open until the liquid level reaches the outer injection opening 7.2. Due to the disturbance of the liquid jet, the force of the liquid jet provided to the deflection portion 6.1 and forwarded by the lev ^¬ er 6.2 is reduced causing the closing of the valve 3 and thereby the automatic stop of the fluid supply.

In the present embodiment, the control element 5 is formed by at least a portion of the first lever arm 6.2.1 of the lever 6.2. By pressing the control element 5 into the housing (as indicated by the arrow), the spring 6.3 is compressed and the valve 3 is opened. Based on the upper-mentioned provision of force by the liquid jet onto the deflector portion 6.1, the valve is stabi ^¬ lized in the open position. So, in other words, the lever 6 does not only provide a transfer of the force applied at the deflec ^¬ tor portion 6.1 to the valve 3 but forms also the control ele ^¬ ment 5. Preferably, also a portion of the second lever arm 6.2.2 is ac ^¬ cessible and can be operated by a user in order to be able to manually stop the provision of liquid into the vessel. As shown in Fig. 3 and 4, a first portion 5.1 of the control element 5 is arranged upstream the pivot axis A and a second portion 5.2 of the control element 5 is arranged downstream the pivot axis A. Thus, by pressing the first portion 5.1, the valve 3 can be opened and by pressing the second portion 5.2, the valve 3 can be manually closed.

In order to avoid that the outer injection opening 7.2 is sealed by an object, e.g. a leaf or the wall of the vessel to be filled with liquid, one or more projections 13 are provided in the area of the outer injection opening 7.2. In the present embodiment, a pair of projections 13 is provided close to the outer injection opening 7.2 wherein the first projection 13 is provided at a first side of the outer injection opening 7.2 and a second pro ^¬ jection 13 is provided at the opposite side of the outer injec ^¬ tion opening 7.2. Said projections 13 may comprise a rib-like cross section and may comprise a ring-like shape thereby at least partly surrounding the shut-off device 1.

In order to avoid that due to a high pressure of the liquid jet the disturbance provided by the liquid sucked in through the in ^¬ ner injection opening 7.1 does not lead to a closing of the valve 3, the automatic shut-off device 1 comprises liquid re ^¬ tarding means 11. In the present embodiment, the liquid retard ^¬ ing means 11 are provided upstream the valve 3, i.e. between the quick connector portion 2.2 and the valve 3. However, said liq ^¬ uid retarding means 11 can also be arranged at another position, for example, between the valve 3 and the nozzle 8. The liquid retarding means 11 may be adapted to cause turbulences within the liquid jet. For example, the liquid retarding means 11 may be build by a grid comprising one or more long holes causing such turbulences within a high pressure liquid jet. According to embodiments, the jet forming portion 12 comprises an opening 12.1. Liquid provided to the jet forming portion 12 may splash back. By means of the opening 12.1, the back- splashing water is at least partially branched off in order to avoid that the back-splashing water undesirably flows out at a housing opening, e.g. the opening providing access to the con ^¬ trol element 5. Said opening 12.1 may be provided opposite or essentially opposite to the liquid dispensing opening 2.3. The branched-off amount of liquid is output at an opening 2.4 of the housing 2. Said opening 2.4 may be arranged close to the outer injection opening 7.2. More in detail, the opening 2.4 may be provided between the jet forming portion 12 and the outer injec ^¬ tion opening 7.2. The opening 2.4 may be separated from the out- er injection opening 7.2 by means of a projection 13 thereby avoiding that liquid output at the opening 2.4 can be sucked in ^¬ to the outer injection opening 7.2.

In order to enable a manually cleaning of the shut-off device 1, the shut-off device 1 can be disassembled. Specifically, the jet forming portion 12 or other portions of the shut-off device 1 can be unscrewed in order to clean interior portions of the shut-off device 1. It should be noted that the description and drawings merely il ^¬ lustrate the principles of the proposed automatic shut-off de ^¬ vice. Those skilled in the art will be able to implement various arrangements that, although not explicitly described or shown herein, embody the principles of the invention. List of reference numerals

1 shut-off device

2 housing

2.1 outer housing wall

2.2 quick connector portion

2.3 liquid dispensing opening

2.4 opening

3 valve

4 liquid path

5 control element

5.1 first portion of the control element

5.2 second portion of the control element

6 closing mechanism

6.1 deflector portion

6.2 lever

6.2.1 first lever arm

6.2.2 second lever arm

6.3 spring

6.4 tappet

7 variation means

7.1 inner injection opening

7.2 outer injection opening

8 nozzle

8.1 rib

9 channel portion

9.1 wall

10 intermediate chamber

11 liquid retarding means

12 jet forming portion

12.1 opening

13 projection

A pivot axis

FD flow direction 1 length of the nozzle

L length of the channel portion wl width of the nozzle channel w2 width of the channel portion