Technical field of the invention

This invention relates to a device for prevention of misfillling, more particularly a device for prevention of misfilling when attempting to fill a compartment, like an underground tank of a petrol station or a fuel tank of a motor vehicle, with the incorrect fuel type. Furthermore, the invention relates to a method for prevention of misfilling.

Background of the Invention

Motor vehicles are equipped with different types of internal combustion engines and accordingly require different fuel types. The majority of motor vehicles use petrol engines or diesel engines and therefore require either petrol fuel or diesel fuel. Fuel is usually stored in a fuel tank of the vehicle and refilled at a petrol station either by the driver or a filling station attendant. Fuel tanks are susceptible to being filled with the incorrect fuel. For example, petrol type fuel can be administered to a vehicle with a diesel engine or diesel type fuel can be administered to a vehicle with a petrol engine. This can be due to communication errors between the driver of the vehicle and the attendant at the petrol station or absent mindedness of persons involved in the refilling process. The associated risk of misfuelling can be as low as the inconvenience and cost for draining and refilling the tank or as high as the repair or replacement of vehicle engine parts, which are damaged while attempting to operate the vehicle's engine with the wrong type of fuel. In order to avoid misfuelling, petrol stations usually provide nozzles of different fuel types with different colours. Although this results in increased attention of a user, misfuelling is not completely ruled out, especially when operating the nozzle in the dark. Furthermore, colour codes may change from country to country, which even can increase potential misfuelling especially when users are confronted with unknown colour codes.

In the prior art devices are known which can be used to utilize different sizes of nozzles for different fuel types. For example, in EP 1790517 B1 a misfuelling prevention device is shown comprising a body that is arranged to be mounted within the refuelling point of a motor vehicle, so that only a specific nozzle can be engaged. However, this type of protection relies on different nozzle sizes and accordingly prevents only misfuelling with petrol pumps of fuels having a larger nozzle diameter. In addition, different nozzle sizes may not be readily available in all countries. The above described problem of misfuelling is even more aggravated when not only a single fuel tank of a car is considered but a fuel storage facility of a petrol station. It is to be appreciated that accidental pumping of wrong fuel into an underground compartment can lead to financial losses by leaving fuel mixtures which are economically worthless. Furthermore, damage to engines of costumers can occur, which further places a huge risk on the owner of a petrol station.

Another potential problem of misfuelling exits with respect to aircrafts, especially light non-commercial aircrafts. There, misfuelling can ultimately result in crash-landing due to engine failure. Many non-commercial aircrafts are operated by either non-professional or occasional pilots and this further aggravates the problem of misfuelling.

In addition to the above described scenarios, other branches of industry would be affected by incorrect filling of a liquid as well. For example, food processing industry often relies on external deliverers for liquid ingredients such as milk, edible oil or the like, which are stored on-site in compartments for later processing. Any misfilling of those compartments would result in huge economic losses by either wasting the ingredients or by resulting in unusable food. Similar precautions as outlined above with respect to fuelling could be applied by are equally insufficient to fully prevent misfilling in all circumstances.

In view of the above, the inventor has therefore identified a need to overcome the above mentioned problems and the disadvantages associated with prior art systems.

Objects of the Invention

It is an object of the present invention to provide a device for prevention of misfilling or a method for prevention of misfilling, which respectively overcome, at least partly, the above identified disadvantages.

It is also an object of the present invention to provide a device for prevention of misfilling or a method for prevention of misfilling which are both novel and involve an inventive step.

Summary of the Invention

Thus, according to a first aspect of the invention there is provided a device for prevention of misfilling which includes:

a locking means operable in a closed position to prevent a liquid flowing through the locking means and in an opened position to allow flowing through the locking means; and

a sensor means being attached to the locking means, wherein the sensor means are capable of sensing the liquid so as to effect the locking means from the normally closed position into the open position for a prescribed liquid. The sensor means may be capable of sensing the specific weight of the liquid. The sensor means may be capable of sensing colour of the liquid.

The sensor means may comprise one floating chamber.

It is to be appreciated that with one floating chamber, the sensor means are capable of discriminating whether the specific weight of the administered liquid is above or below the specific weight of the prescribed liquid. The sensor means may comprise two floating chambers.

It is to be appreciated that with two floating chamber, the sensor means are capable of discriminating whether the specific weight of the administered liquid is within a predetermined range of a specific weight of the prescribed liquid.

The floating chamber may comprise two multi compartment cylinders capable to slide within each other.

The two floating chambers may be leveraging on opposite sides of a support.

The device may further comprise a low friction telescopic combination valve. The device may further comprise a spring loaded normally-closed gate valve with a latch. The device may further comprise a temporary weight in the form of a container to collect liquid and use the added weight to open the latch. The device may further comprise a tube connecting the telescopic valve with the temporary weight container.

The two floating chambers may be weighted so that the first chamber sinks and the second chamber floats in the prescribed liquid. The two floating chambers may be designed to behave with the same coefficient of thermal expansion as the prescribed liquid.

The two floating chambers may comprise a flexible membrane. The two floating chambers may comprise a piston. The two floating chambers may comprise an air filled float body. The two floating chambers may comprise a working liquid filled tube.

The two floating chambers may be designed such that with the working liquid expanding or contracting with the rise and fall in temperature the piston acts to push or pull the membrane.

The two floating chambers may be designed such that with the proportions of the float body and tube selected according to the working liquid and the prescribed liquid's coefficient of thermal expansion (CTE) the float can behave with the same CTE as the prescribed liquid, wherein the float sinks or floats in the liquid irrespective of the temperature.

The two floating chambers may be designed such that a one-floats-one- sinks condition is present so as to open the valve means when the liquid being administered is the prescribed liquid.

The prescribed liquid may be a fuel for a combustion engine. The prescribed liquid may be petrol. The prescribed liquid may be diesel. The prescribed liquid may be avgas. The prescribed liquid may be kerosene.

The device may be operated with an override mechanism capable of bypassing the sensor means so as to open the valve means.

The device may be arranged within a filler tube. The filler tube may be connected to a tank of a vehicle. The filler tube may be connected to a compartment of a filling station.

According to a second aspect of the invention there is provided a method for prevention of misfilling which includes:

operating a locking means in a closed position to prevent a liquid flowing through the locking means and in an opened position to allow flowing through the locking means; and

providing a sensor means being attached to the valve means, wherein the sensor means are capable of sensing the specific weight and/or colour of the liquid so as to effect the locking means from the normally closed position into the open position for a prescribed liquid.

According to a third aspect of the invention there is provided a fuel tank for a vehicle, the fuel tank being attached to a filler tube which includes:

a locking means operable in a closed position to prevent a liquid flowing through the locking means and in an opened position to allow flowing through the locking means; and

a sensor means being attached to the locking means, wherein the sensor means are capable of sensing the specific weight and/or colour of the liquid so as to effect the locking means from the normally closed position into the open position for a prescribed liquid.

According to a fourth aspect of the invention there is provided a fuel tank for a filling station, the fuel tank being attached to a filler tube which includes: a locking means operable in a closed position to prevent a liquid flowing through the locking means and in an opened position to allow flowing through the locking means; and

a sensor means being attached to the locking means, wherein the sensor means are capable of sensing the specific weight and/or colour of the liquid so as to effect the locking means from the normally closed position into the open position for a prescribed liquid.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in greater detail by way of non-limiting examples with reference to the following drawing in which: Figure 1 shows a perspective side view of a device for prevention of misfuelling according to an embodiment of the present invention;

Figure 2 shows a detail of the device for prevention of misfuelling according to Figure 1 in a perspective side view;

Figure 3 shows a cross-sectional side view of the device for prevention of misfuelling according to Figure 1 ;

Figure 4 shows a further detail of the device for prevention of misfuelling according to Figure 1 in a perspective side view;

Figure 5 shows a cross-sectional side view of the device for prevention of misfuelling according to Figure 4; Figure 6 shows a further detail of the device for prevention of misfuelling according to Figure 1 in a perspective side view;

Figure 7 shows a cross-sectional side view of the device for prevention of misfuelling according to Figure 6; Figure 8 shows a side view of the device for prevention of misfuelling according to Figure 6;

Figure 9 shows a detail of the device for prevention of misfuelling according to Figure 1 in a perspective side view; and

Figure 10 shows a cross-sectional side view of the device for prevention of misfuelling according to Figure 9; Figure 11 shows a further detail of the device for prevention of misfuelling according to an embodiment of the invention in a perspective side view;

Figure 12 shows a cross-sectional side view of the device for prevention of misfuelling according to Figure 11 ;

Figure 13 shows a detail of the device for prevention of misfuelling according to an embodiment of the invention in a perspective side view; Figure 14 shows a cross-sectional side view of the device for prevention of misfilling according to an embodiment of the invention;

Figure 15 shows a further cross-sectional side view of the device for prevention of misfilling according to Figure 14;

Figure 16 shows a further cross-sectional side view of the device for prevention of misfilling according to Figure 14;

Figure 17 shows a detail of the device according to Figure 14 in a side view; Figure 18 shows a further detail of the device according to Figure 14 in a side view;

Figure 19 shows a further detail of the device according to Figure 14 in a side view;

Figure 20 shows a further detail of the device according to Figure 14 in a side view; and Figure 21 shows a further detail of the device according to Figure 14 in a side view.

Detailed Description with Reference to the Drawings

With reference to the accompanying drawings, a device for prevention of misfuelling, in accordance with the invention, is generally indicated by reference numeral 10. In the drawings, like reference numerals refer to like parts, unless otherwise indicated.

The device 10 for prevention of misfuelling is placed within a compartment 12, as schematically indicated by the hatched line in Figure 3. The compartment 12 can either be a fuel tank for a vehicle or a fuel tank for a filling station. The compartment 12 is attached to a filler tube 14. The filler tube 14 can form an integral part of the compartment 12 or be provided as a separate item depending on the requirements. It is to be appreciated that the term "vehicle" generally refers to all conceivable means of transport which includes land-, water- or airborne devices. Vehicles according to the invention are equipped with an internal combustion engine, which requires administering of a prescribed fuel. For example, the vehicle can be a passenger car, a truck, a bus, a boat, or an aircraft. These examples, however, are not to be construed as to limiting the invention.

The device 10 for prevention of misfuelling further includes a locking means 20 operable in a closed position to prevent a liquid flowing through the locking means 20 and in an opened position to allow flowing through the locking means 20. The device 10 for prevention of misfuelling further includes a sensor means 30 being attached to the locking means 20, wherein the sensor means 30 are capable of sensing the specific weight of the liquid so as to allow the locking means 20 from the normally closed position into the open position for a prescribed liquid. The sensor means 30 includes two specially designed floating chambers

31 and 32, which are leveraging on opposite sides of a support 34. The floating chambers 31 and 32 are designed to behave with the same coefficient of thermal expansion as the prescribed liquid it is designed to allow into the tank 12. It is also conceivable to use only one float. One float will be adequate to avoid the majority of misfuelling by allowing only liquids above or below a certain density. An example for such a device will be given below. The scheme with two floats prevents misfuelling by allowing only liquids within a specific range to pass. Furthermore, the device 10 for prevention of misfuelling further includes a low friction telescopic combination valve 40, a spring loaded normally-closed gate valve 50, and a temporary weight 60 in the form of a container to collect liquid and use the added weight to open a latch 54 of the normally-closed gate valve 50 having a gate 52. A tube 62 is connecting the telescopic valve 40 with the temporary weight container 60. The telescopic combination valve 40 allows liquid to pass down the tube 62 past the gate valve 50 to the temporary weight container 60, which opens the latch 54 with the added weight of the liquid. It is also conceivable to use two normal low friction valves, connected in series, as an alternative to the telescopic combination valve 40.

The telescopic combination valve 40 is explained on the hand of three conditions of the valve with sections cut away for explanation purposes, as depicted in Figures 9 and 10. The valve consists of three tubes 42, 44, 46 fitting within each other. The outer tube 42 is fixed and passes the liquid into downstream piping. In other embodiments (see below with respect to Figure 14) the inner tube may be used to convey the liquid downstream Each tube 42, 44, 46 has holes 42', 44', 46' at set distances from the bottom side of the respective tube. These tubes can slide up or down, in this case depending on whether the float 31 , 32 sinks or floats.

In the first condition of the valve 40 as indicated in the left schematic denoted a) both the inner tubes 44, 46 rose to their top positions. In the second condition of the valve 40 as indicated in the middle schematic b) both inner tubes 44, 46 dropped to their bottom positions. In the third condition of the valve 40 as indicated in the right schematic c) the middle tube 44 rose and the inner tube 46 dropped. Accordingly, the holes 42', 44', 46' only line up in the last condition, thus allowing liquid to pass.

This invention uses the density of the liquid administered to a tank 12 to make floats 31 , 32 either rise or sink. The buoyant forces of these floats 31 , 32 are small but with the use of a low friction telescopic combination valve 40 some liquid can be passed and the weight of this liquid can exert a greater force. This greater force is then used to open the latch 54. The pressure of the fuel inside the filler tube 12 will then open the gate 52 of gate valve 50. The temporary weight container 60 collecting the liquid will have a slow self draining feature in the form of a small hole to allow the valve 50 resetting after a few minutes. The gate 52 and the latch 54 are therefore also spring loaded to enable this resetting of the valve 50.

In another embodiment of the invention a sufficiently large upstream tank (not shown in the figures) is present above the fuel mix prevention device 10 to enable seamless refueling. In other words the time needed for the locking means 30 to 'decide' whether to allow the liquid is not noticed by the operator as the valve opens before this additional tank above fuel mix prevention device 10 is full. The risk of miss fuelling is thus minimized to the amount of liquid collected in this upstream tank. The valve could also be fitted with a feature to easily drain all the liquid above the gate valve in case miss fuelling did occur. In another embodiment of the invention a manual override switch is included. In this case fuel outside the design density range can be administered to the tank 12. The additional supervision needed in this instance will still prevent the misfuelling of the tank. The float 31, 32 includes the following: a flexible membrane 35, a piston

36, an air filled float body 37, a piston seal 38 and a working liquid filled tube 39. It should be noted that alternative arrangements of the floats can be used either with the combination valve or with other type of valves. With the working liquid expanding or contracting with the rise and fall in temperature the piston 36 will push or pull the membrane 35. With the proportions of the float body 37 and tube selected according to the working liquid and the design fuel's coefficient of thermal expansion (CTE) the float 31 , 32 can behave with the same CTE as the design fuel. The float 31 , 32 will therefore sink or float in a liquid irrespective of the temperature. When two of these floats, for instance, are weighted so that one will sink and the other will float in petrol; one can assume the liquid being administered is petrol when this one-floats-one-sinks condition is present. This assumption is based on the fact that the liquid administered is within a specific density range. The same holds for diesel.

In another embodiment of the invention the floats includes a further tube connecting the air filled float body 37 with the atmosphere. This will compensate for the differences in air pressure because of altitude changes. This feature allows the float's membrane 35 to behave in accordance with the designed CTE irrespective of the altitude.

In another embodiment of the invention the floats 31 , 32 are designed where no flexible member but rather two multi compartment cylinders 80, 81 able to slide within each other are present, see figure 1 and 12.

The two cylinders fit within each other to form the two concentric compartments. So there is an inner and outer cylinder as well as a inner and outer compartment. In figure 12, the inner compartment 82 and outer compartment 83 are indicated. The two cylinders fit tightly enough within each other to allow an airtight seal for both compartments 82 and 83.

The outer cylinder of the two concentric compartments contains the working liquid and the inner one contains air. As the working liquid expands and contracts, the float will change its density. This concept is similar to the previously described embodiment except for the omission of the flexible member and the piston being integrated into the float body.

The float described above can also be used without any levers, see figure 13. Although the resulting buoyancy forces are quite small, they can nevertheless be used to operate the valve 40. In the first condition of the valve 40 as indicated in the left schematic denoted a) both the inner tubes 44, 46 rose to their top positions. In the second condition of the valve 40 as indicated in the middle schematic b) both inner tubes 44, 46 dropped to their bottom positions. In the third condition of the valve 40 as indicated in the right schematic c) the middle tube 44 rose and the inner tube 46 dropped. Accordingly, the holes 42', 44', 46' only line up in the last condition, thus allowing liquid to pass.

Making now reference to Fig. 14, a further embodiment of the invention is described. The device 10 includes a section covered by an outer cover or housing as explained with reference to Fig. 1. The side of the device 10 being located in the filler tube is referred to as the wet side in the following, it is separated from the dry side by a wall 98.

Similar to the previous embodiments, the device 10 for prevention of misfilling includes the locking means 20 operable in a closed position to prevent a liquid flowing through the locking means 20 and in an opened position to allow flowing through the locking means 20. The device 10 for prevention of misfuelling further includes a sensor means 30 being attached to the locking means 20, wherein the sensor means 30 are capable of sensing the specific weight of the liquid so as to allow the locking means 20 from the normally closed position into the open position for a prescribed liquid.

The sensor means 30 includes a floating chamber 31 , which is leveraging on opposite sides of the support 34 with a micro valve 90. The lever is slotted at the middle support, as depicted in Fig. 17. Furthermore, the device 10 includes micro valve 90, a gate valve 50, and a temporary weight 60 in the form of a container to collect liquid and use the added weight to open a latch 54 of the gate 52. A tube 62 is connecting the temporary weight container 60. 11 000047

The micro valve 90 allows liquid to pass down the tube 62 past the gate valve 50 to the temporary weight container 60, which opens the latch 54 with the added weight of the liquid, as depicted in Fig. 20. The telescopic combination valve 40 is explained on the hand of three conditions of the valve with sections cut away for explanation purposes, as depicted in Figures 17 and 18. The valve consists of two tubes 42, 44 fitting within each other. The outer tube 42 is fixed to the leverage 34. The inner tube 44 is fixed to the micro valve 90. Each tube 42, 44 have holes 42', 44' at set distances from the bottom side of the respective tube. These tubes can slide up or down, in this case depending on whether the float 31 sinks or floats.

In the first condition of the valve as indicated in the schematic denoted a) the float is in the bottom position such that the outer tube 42 rose to the top position. When a liquid of adequate density is administered to the valve, the float 31 will start to rise. Due to the low friction of the micro valve the float 31 will rise despite marginally adequate densities. In the second condition of the valve 40 as indicated in the schematic b), the float is in a transient or middle position and the corresponding tube 42 follows to a middle position as well. In the third condition of the valve as indicated in the schematic c), the float 31 will rise to a point where the valve hits the bottom rest. Only in this case the holes 42', 44' line up thus allowing liquid to pass.

With the valve 90 in an open position, liquid is allowed to pass to the dry side of the valve. The temporary weight 60 fills up with liquid through channel 62 thus increasing its weight. When the weight of the temporary weight 60 overcomes a counterweight 94 being located on a lever 96, the latch 54 will open, as depicted in Fig. 9. With the latch 54 open, the gate 52 can swing open allowing the administered liquid to pass unhindered, see Fig. 20. It is to be noted that instead of weight other concepts for opening the latch can be employed. For example, the pressure of the liquid can be used to open the latch 54, instead of Z 2011/000047 only the weight inside the temporary weight 60. This entails the use of some hydraulic cylinder on the dry side to convert the pressure to a force, for example. Accordingly, the speed of operation in the current concept can be improved in some instances.

The float 31 is designed to behave with the same Coefficient of Thermal Expansion (CTE) as the liquid it needs to allow into the tank. This will prevent incorrect liquid at very high or very low temperatures to pass due to a decrease or increase of density due to its temperature. The float 31 is shown in a cross- sectional view in Fig. 21. Similar to the previous embodiments, the float 31 includes the following: a membrane 35, a piston 36, an air filled float body 37, a piston sealing 38 and a working liquid filled tube 39. In this embodiment, the membrane is not flexible but a cap is able to slide up and down on the float body 37. The cap can be sealed by two o-rings in this specific concept.

According to another embodiment of the invention a method for prevention of misfilling includes operating a locking means 20 in a closed position to prevent a liquid flowing through the locking means and in an opened position to allow flowing through the locking means 20; and providing a sensor means 30 being attached to the locking means 20, wherein the sensor means 30 are capable of sensing the specific weight of the liquid so as to effect the locking means 20 from the normally closed position into the open position for a prescribed liquid.

As outlined above, the prescribed liquid may be a fuel for a combustion engine including petrol, diesel, avgas or kerosene, for example. It is to be appreciated that the device 10 for prevention of misfuelling is capable of sensing different fuel types as long as their density difference does not become too small.

It should be noted that another type of sensor and quality of the fuel can be measured as well, for example colour. Most fuels are dyed nowadays with different fuel types having different colours. Accordingly, an electronic device can be used to detect the colour of the fuel and the gate valve can be operated as a result of the sensor output. This concept can either be implemented as an alternative to the measurement of the density of the fuel on buoyancy forces or as an additional measure, in case density differences between different fuel types are too low in order to be detected.

Furthermore, many of the above embodiments were described with respect to the application of fuel tanks. It is to be appreciated however that the inventive concept can be applied to all filling process involving a liquid. The application towards fuel compartments should therefore not be construed as limiting the invention.

Although certain embodiments only have been described herein, it will be readily apparent to any person skilled in the art that other modifications and/or variations of the invention are possible. Such modifications and/or variations are therefore to be considered as falling within the spirit and scope of the invention as herein described and/or exemplified.