Dispenser for dispensing LPG-based fuel for endothermic diesel-cycle engine and respective dispensing method

Abstract

A dispenser for dispensing LPG-based fuel for endothermic Diesel-cycle engines is described. The dispenser (100) comprises a hydraulic circuit (CIp) for supplying a primary component of the LPG-based fuel, wherein the primary component is constituted by LPG; a hydraulic circuit (Cis) for supplying a secondary component of the LPG-based fuel, wherein the secondary component is constituted by diesel fuel or its homologues; a hose (13) for dispensing the primary component, which has an end connected to the hydraulic circuit (CIp) for supplying the primary component and the other end provided with a nozzle (15) for dispensing the primary component; a hose (14) for dispensing the secondary component, which has an end connected to the hydraulic circuit (Cis) for supplying the secondary component and the other end provided with a nozzle (16) for dispensing the secondary component. The nozzle (16) for dispensing the secondary component and the nozzle (15) for dispensing the primary component are operable in sequence for dispensing a predetermined volumetric quantity of said secondary component and a predetermined volumetric quantity of said primary component into a tank, so as to obtain an LPG- based fuel which has an LPG content ranging between at least 51% and 80%, limits included. The invention also concerns a kit for dispensing LPG-based fuel for endothermic Diesel-cycle engines, a tank for containing LPG-based fuel, a device for cooling LPG-based fuel and a method for dispensing LPG-based fuel for endothermic Diesel-cycle engines.

Description

[0001] DISPENSER FOR DISPENSING LPG-BASED FUEL FOR ENDOTHERMIC DIESEL-CYCLE ENGINES AND RESPECTIVE DISPENSING METHOD

[0002] Field of the invention

[0003] The present invention generally concerns the technical field of dispensers for dispensing fuels. In particular, the present invention concerns a dispenser for dispensing LPG-based fuel for endothermic Diesel-cycle engines and a respective dispensing method.

[0004] Known art

[0005] It is known that automotive fuels, once burned inside an engine, generate emissions into the atmosphere, which are one of the leading causes of poor air quality. When used for supplying endothermic engines on wheeled vehicles for the transport of goods and people, such fuels, mainly gasoline and diesel fuel, are reported as one of the major causes of CO2 emissions into the air and give rise to the well-known “greenhouse effect”, with its equally well-known consequences, such as the so-named “global warming”.

[0006] For the purposes set forth above, it is further known that liquefied petroleum gases, LPG in short, which are none other than a mixture of low molecular weight alkane hydrocarbons composed mainly of propane and butane with small amounts of ethane and unsaturated hydrocarbons, such as ethylene and butene, are often used.

[0007] It is further known that LPG is liquefied by compression at relatively low pressures, generally between 2 and 8 bars, to reduce its size and to make it so that its transportation is more economical and can occur at ambient temperature. This way a hundreds-fold increase in the density of the mixture is obtained compared to the gaseous state, therefore reducing its volume for the same mass.

[0008] It is important to note that LPG is an easily available fuel, it has low environmental impact and high energy and heat efficiency. In particular, if compared with gasoline and diesel fuel, it generates less CO2 emissions, respectively equal to - 32% and -39%. Moreover, when burned in the endothermic combustion process of an engine, LPG develops lower quantities of NOXs and particulate matter when compared to gasoline and diesel fuel.

[0009] Among the endothermic engines used, in particular in the trucking industry but also in agricultural vehicles, generators, boats and locomotives, Diesel-cycle ones are particularly common and such engines are supplied by diesel fuel in most cases. However, with appropriate adjustments to the engine, it is also possible to use fuels obtained from renewable sources, such as for example biodiesel, bioethanol, dimethyl ether (DME), as other less polluting fuels that can emit a lesser quantity of CO2 than the one emitted by diesel fuel.

[0010] It is also known that it is possible to supply Diesel-cycle engines with LPG. In particular, devices installed aboard the engines, adapted for allowing the supply of engines by mixing diesel fuel or the alternative fuels set forth above with LPG, which is injected at the gaseous state into the air intake pipes to the engine, are known.

[0011] This technique is known as “fumigation” and generally provides for the presence of a pump which pushes LPG, still at the liquid state, into a vaporizer, which transforms it into its gaseous phase. LPG, still in the gaseous phase, is subsequently injected into the engine’s air intake pipe. Specific electronics (named ECU) control the stroke and injection times of the injectors, therefore determining the amount of LPG fed into to engine to provide the energy requirements of the various steps of its operation.

[0012] Main object of the present invention is therefore to provide a dispenser and a method of dispensing an LPG-based fuel for supplying endothermic Diesel-cycle engines.

[0013] A further object of the present invention is to provide a dispenser and a method for dispensing an LPG-based fuel for endothermic Diesel-cycle engines, such that an LPG-based fuel can be dispensed with a variable LPG content depending on the type of vehicle to be refueled.

[0014] A further object of the present invention is to provide a dispenser and a method for dispensing an LPG-based fuel for endothermic Diesel-cycle engines, such as to supply all the Diesel-cycle engines used in the many types and applications of wheeled land transportation, in power plants, on locomotives, in marine recreational boats, on earth-moving machinery and agricultural tractors.

[0015] Still a further object of the present invention is to provide a dispenser for dispensing fuel for endothermic Diesel-cycle engines, which can be implemented within competitive times and costs.

[0016] Another object of the present invention is to provide a dispenser and a method for dispensing an LPG-based fuel for endothermic Diesel-cycle engines, which can be made / obtained wherever LPG and diesel fuel and / or its homologues are available.

[0017] Summary of the invention

[0018] These and further objects of the present invention are achieved thanks to a dispenser for dispensing LPG-based fuel for endothermic Diesel-cycle engines, a kit for dispensing LPG-based fuel for Diesel-cycle engines, a tank for containing LPG- based fuel, a device for cooling LPG-based fuel and a method for dispensing LPG- based fuel for endothermic Diesel-cycle engines according to independent claims 1, 8, 9, 11 and 12.

[0019] Further preferential characteristics and aspects of the invention are set out in the dependent claims.

[0020] In a first aspect, the invention therefore concerns a dispenser for dispensing LPG-based fuel for endothermic Diesel-cycle engines, characterized by comprising: a hydraulic circuit for supplying a primary component of the LPG-based fuel, wherein the primary component is constituted by LPG; a hydraulic circuit for supplying a secondary component of the LPG-based fuel, wherein the secondary component is constituted by diesel fuel or its homologues; a hose for dispensing the primary component, which has an end connected to the hydraulic circuit for supplying the primary component and the other end provided with a nozzle for dispensing the primary component; and a hose for dispensing the secondary component, which has an end connected to the hydraulic circuit for supplying the secondary component and the other end provided with a nozzle for dispensing the secondary component. The nozzle for dispensing the secondary component and the nozzle for dispensing the primary component are operable in sequence for dispensing a predetermined and measured volumetric quantity of the secondary component and a predetermined and measured volumetric quantity of the primary component into a tank, so as to obtain an LPG- based fuel which has an LPG content ranging between at least 51% and 80%, limits included.

[0021] In an embodiment, the dispenser comprises explosion-proof keypads for respectively presetting a volumetric quantity or an amount of the primary component of the LPG-based fuel to be dispensed and a volumetric quantity or an amount of the secondary component of the LPG-based fuel to be dispensed and start / stop levers, or ON-OFF buttons, of the hydraulic circuits for supplying the primary component and the secondary component.

[0022] In an embodiment, the dispenser further comprises volumetric electronic heads for the primary and secondary components and displays for displaying the dispensed volumetric quantity of the primary component and secondary component.

[0023] In an embodiment, the dispenser further comprises electronic metering heads respectively for the primary component and the secondary component of the LPG- based fuel, each comprising a display for displaying the amount of the respective component dispensed, a display for displaying the volumetric quantity of the respective component dispensed, and a display for displaying the price per dispensed unit of the respective component dispensed.

[0024] In an embodiment, the dispenser further comprises, for the primary and secondary components of the LPG-based fuel, a red light, a green light and an acoustic signalling device.

[0025] In an embodiment, the dispenser further comprises a vehicle recognition system which comprises an RFID reader fixed on a containing body of the dispenser and in electrical communication with the electronic metering heads, wherein the RFID reader is configured for communicating with an RFID transponder of a user of a vehicle to be refueled with the LPG-based fuel and with a computing unit of the dispenser, and wherein data relating to the vehicle, the engine of the vehicle and / or the user of the vehicle is stored in the RFID transponder.

[0026] In an embodiment, the vehicle recognition system further comprises a sensor positioned at the nozzle for dispensing the primary component of the LPG-based fuel and a sensor positioned at the nozzle for dispensing the secondary component of the LPG-based fuel. The sensors are configured for real-time reading information relating to the level of fuel present in the tank of a vehicle and sending it to the computing unit.

[0027] In an embodiment, the nozzles are of the high-flow rate or low-flow rate type.

[0028] In a second aspect, the invention concerns a kit for dispensing an LPG-based fuel for endothermic Diesel-cycle engines, characterized by comprising: an RFID reader in communication with a computing unit; an RFID transponder; at least one pair of dispensing tubes, each provided with a respective dispensing nozzle provided with a sensor, one tube being intended for dispensing a primary component of an LPG-based fuel and the other tube being intended for dispensing a secondary component of the LPG-based fuel; and a pair of green light - red light - acoustic signalling device sets, one set being combined with the primary component of the LPG-based fuel and the other set being combined with the secondary component of the LPG-based fuel.

[0029] In a third aspect, the invention concerns a tank for use with a dispenser as defined above, characterized by comprising, inside it, a level indicator preferably of the magnetostrictive technology type, wherein the level indicator is adapted for cooperating with the sensor positioned at the nozzle for dispensing the primary component of the LPG-based fuel and with the sensor positioned at the nozzle for dispensing the secondary component of the LPG-based fuel.

[0030] In an embodiment, the tank further comprises a safety sensor configured for blocking the flow, inside the tank, of the secondary component and the primary component of the LPG-based fuel.

[0031] In a fourth aspect, the invention concerns a cooling device for use with a tank as defined above. The cooling device is characterized by comprising: a cooling coil; an inlet connection and an outlet connection of coolant; an inlet connection of a hot LPG- based fuel coming from an engine of a vehicle; an inlet connection of the ambient temperature LPG-based fuel coming from the tank and an outlet connection of the cold LPG-based fuel, towards the engine. In a fifth aspect, the invention concerns a method for dispensing an LPG-based fuel for endothermic Diesel-cycle engines, performed by using the dispenser or the dispensing kit as defined above. The method comprises the following steps, carried out in sequence:

[0032] - dispensing, into a tank, a volumetric quantity of a secondary component of the LPG-based fuel;

[0033] - dispensing, into the same tank, a volumetric quantity of a primary component of the LPG-based fuel; and

[0034] - self-mixing, inside the tank, the primary and secondary components, so as to obtain the LPG-based fuel which has an LPG content ranging between at least 51% and 80%, limits included.

[0035] In an embodiment, the method comprises, upstream of the dispensing steps, a step of recognizing vehicles, comprising the following steps:

[0036] - transmitting, from an RFID transponder to an RFID reader, data relating to a vehicle to be refueled with the LPG-based fuel;

[0037] - transmitting, from the RFID reader to a computing unit, the data received;

[0038] - comparing, by the computing unit, the data received with data in a database; and

[0039] - if the information received does not match that in the database, denying consent, by the computing unit, to dispense and switching on the red lights, respectively of the primary component and the secondary component of the LPG- based fuel;

[0040] - if the information received matches that in the database, switching on, by the computing unit, the green lights, respectively of the secondary and primary components of the LPG-based fuel, and starting dispensing.

[0041] In an embodiment, the step of dispensing the secondary component into the tank comprises the following steps, performed by the computing unit:

[0042] - calculating the volume occupied by the secondary component of the LPG- based fuel, parameterizing it to the unit price and the value set by a user;

[0043] - adding, to this calculated volume, the volume that will be occupied by the primary component, again parameterizing it to the price read;

[0044] - checking if the space available inside the tank can receive the refueling volume required, and if the total refueling volume cannot be stored inside the tank, denying consent to dispense, keeping the lights of both components on, if the total refueling volume can be stored inside the tank, allowing sequential dispensing of the two components, until reaching the programmed dispensing volumes.

[0045] In an embodiment, during the step of dispensing the primary component into the tank, the computing unit checks in real time that the increase in fuel level inside the tank remains within the calculated limits.

[0046] Brief description of the drawings

[0047] Further characteristics and advantages of the dispenser for dispensing LPG- based fuel for endothermic Diesel-cycle engines, of the dispensing kit of a dispenser, of the tank for use with the dispenser, of the cooling device and the method of dispensing LPG-based fuel for endothermic Diesel-cycle engines according to the present invention will become clearer from the following description set forth with reference to the accompanying figures, which illustrate exemplary embodiments provided for illustrative purposes, and therefore not limiting, in which identical or corresponding parts are denoted by the same numbers of reference. In particular:

[0048] - figure 1 is a schematic front view of a dispenser for dispensing LPG-based fuel for endothermic Diesel-cycle engines according to a first embodiment of the present invention;

[0049] - figure 2 is a schematic front view of a variant of the dispenser of figure 1;

[0050] - figure 3 is a schematic front view of a dispenser for dispensing LPG-based fuel for endothermic Diesel-cycle engines according to a second embodiment of the present invention;

[0051] - figure 4 is a schematic front view of a variant of the dispenser of figure 3;

[0052] - figure 5 is a block diagram which illustrates the operation of a vehicle recognition system of the dispenser according to the present invention; - figure 6 schematically shows the components of a kit for dispensing an LPG- based fuel to be installed on any dispenser of the known type, found at refueling points where both LPG and diesel fuel are dispensed;

[0053] - figure 7 is a schematic front view of a tank positioned aboard a vehicle and configured for containing the LPG-based fuel dispensed with the dispenser according to the present invention;

[0054] - figure 8 is a schematic side view of the tank of figure 7;

[0055] - figure 9 is a schematic sectional view of a cooling device of the LPG-based fuel dispensed into the tank of the engine of a vehicle; and

[0056] - figure 10 is a schematic view of the operating diagram of a cooling device according to the present invention.

[0057] Detailed description of embodiments of the invention

[0058] With reference to figure 1, a dispenser for dispensing LPG-based fuel for endothermic Diesel-cycle engines according to a first embodiment of the present is illustrated therein.

[0059] The dispenser, generally denoted by the number of reference 100, comprises a containing body or cabinet 10, which includes a lower portion 11 and an upper portion 12. The cabinet 10 can take different forms depending on the oil company using it.

[0060] The LPG-based fuel is obtained as a result of natural self-mixing, inside an appropriate tank, of a primary component, specifically LPG, and a secondary component, for example diesel fuel or its homologues, which are preferably obtained from renewable sources, for example biodiesel, bioethanol or DME. LPG-based fuel has an LPG content ranging between at least 51% and 80%, limits included. The LPG- based fuel preferably has an LPG content ranging between at least 51% and 65%, limits included.

[0061] In the following of the present description, reference will be made to diesel fuel as secondary component of the LPG-based fuel.

[0062] A hydraulic circuit CIp for supplying LPG and a hydraulic circuit Cis for supplying diesel fuel are housed in the lower portion 11 of the cabinet 10.

[0063] The tank can be a tank aboard a tanker, a storage tank fixed on the ground or a tank of an engine of a vehicle, such as for example a heavy vehicle or a motor vehicle.

[0064] The dispenser 100 is adapted for being used in dispensing LPG-based fuel in depots of fuel retailers or in fuel depots of diesel fuel users which, for environmental and / or economic reasons, desire to use the LPG-based fuel for self-consumption, in particular, fuel depots located at fleets of heavy vehicles, buses, locomotives, recreational boats or electricity generating sets in which there are already a facility for storing and dispensing diesel fuel intended for supplying engines and the facility for manipulating LPG and the LPG-based fuel obtained / used therefrom.

[0065] In the embodiment illustrated in figure 1, the hydraulic circuit CIp for supplying LPG is housed on the right of the lower portion 11 of the cabinet 10, whereas the hydraulic circuit Cis for supplying diesel fuel is housed on the left of the lower part 11 of the cabinet 10. Of course, and without departing form the protection scope of the present invention, it is possible to provide the hydraulic circuit CIp for supplying LPG on the left in the lower part 11 of the cabinet 10 and the hydraulic circuit Cis for supplying LPG on the right in the lower part 11 of the cabinet 10. LPG and diesel fuel are supplied to the corresponding hydraulic supply circuit by means of respective pumps (not shown). The hydraulic circuits for supplying LPG and diesel fuel are of the known type and will not be described in detail herein.

[0066] The dispenser 100 further comprises a hose 13 for dispensing LPG and a hose 14 for dispensing diesel fuel. The hose 13 has an end connected to the hydraulic circuit CIp for dispensing LPG and a nozzle 15 for dispensing LPG is mounted at the other end. The hose 14 has an end connected to the hydraulic circuit Cis for dispensing diesel fuel and a nozzle 16 for dispensing diesel fuel is mounted at the other end. The nozzles 15 and 16 are of the high-flow rate type and have zero leakage upon disconnection from the tank into which diesel fuel and LPG are supplied and, thanks to their intrinsic characteristics, they naturally self-mix, so as to obtain a chemically and physically stable LPG-based fuel, i.e. such as not to develop any oxidative process which could alter its chemical composition and / or physical characteristics.

[0067] More in particular, the LPG-based fuel thus created is a mixture of hydrocarbons in which the free electrons gravitating about the nucleus of their molecules bind together permanently and irreversibly during mixing (always under unchanged temperature and pressure conditions), therefore creating a new chemical element which acquires its unique and peculiar characteristics, such as chemical composition, specific weight, calorific value. The stability of the LPG-based fuel obtained is certain due to the application of Lavoisier’s “Law of Conservation of Mass”, according to which in a closed system, the storage tank 20 precisely, the total mass of a compound, the LPG-based fuel, is equal to the mass of a first component of the compound, the primary component constituted by LPG, added to the mass of a second component of the compound, the secondary compound, for example diesel fuel.

[0068] Once fed into the supply tank of an engine, the LPG-based compound undergoes a cooling process to a temperature of between 0°C and 2°C, which keeps the mass percent composition between LPG and diesel fuel stable by preventing the LPG from evaporating.

[0069] A housing 17 for the nozzle 15 for dispensing LPG and a housing 18 for the nozzle 16 for dispensing diesel fuel protrude from the upper portion 12 of the cabinet 10. Moreover, respective start / stop levers, or ON-OFF buttons, 19 and 20 of the respective pump for supplying LPG and diesel fuel extend always from the upper portion, preferably below the housing 17 and the housing 18, respectively.

[0070] Explosion-proof keypads 21 and 22 for respectively presetting, by a user, a volumetric quantity of LPG and a volumetric quantity of diesel fuel to be dispensed, volumetric electronic heads 23, 24, respectively for LPG and diesel fuel, and displays 25, 26 for respectively displaying the dispensed volumetric quantity of LPG and diesel fuel, are further present in the upper portion 20 of the cabinet 10.

[0071] With reference to figure 2, a dispenser for dispensing LPG-based fuel according to a variant of the dispenser 100 described above and illustrated in figure 1 is illustrated therein.

[0072] This dispenser, generally denoted by the number of reference 1100, is adapted for use in fuel depots of users who wish to use LPG-based fuel for self-consumption, in particular for refueling cars, and differs from the dispenser 100 for the different type of nozzles for dispensing LPG and diesel fuel.

[0073] The dispenser 1100 therefore comprises a containing body or cabinet 10 which includes a lower portion 11 in which a hydraulic circuit CIp for dispensing LPG and a hydraulic circuit Cis for dispensing diesel fuel are housed.

[0074] The dispenser 1100 further comprises a hose 13 for dispensing LPG and a hose 14 for dispensing diesel fuel. The hose 13 has an end connected to the hydraulic circuit CIp for dispensing LPG and a nozzle 115 for dispensing LPG is mounted at the other end. The hose 14 has an end connected to the hydraulic circuit CPs for dispensing diesel fuel and a nozzle 116 for dispensing diesel fuel is mounted at the other end. The nozzles 115 and 116 supply the tank inside which diesel fuel and LPG naturally selfmix, thanks to their intrinsic characteristics, so as to obtain a chemically and physically stable LPG-based fuel, as defined above. The tank has the same characteristics as the tanks of the known type used in the conversion of Otto cycle engines to LPG and will therefore not be described in detail herein.

[0075] A housing 117 for the nozzle 115 for dispensing LPG and a housing 118 for the nozzle 116 for dispensing diesel fuel protrude from the upper portion 12 of the cabinet 10. Moreover, respective start / stop levers, or ON-OFF buttons, 19 and 20 of the respective pump for supplying LPG and diesel fuel extend always from the upper portion, preferably below the housing 117 and the housing 118, respectively.

[0076] Explosion-proof keypads 21 and 22 for respectively presetting the LPG quantity and the diesel fuel quantity to be dispensed, volumetric electronic heads 23, 24, respectively for LPG and diesel fuel, and displays 25, 26 for respectively displaying the dispensed quantity of LPG and diesel fuel, are further present in the upper portion 20 of the cabinet 10.

[0077] The operation of the dispensers 100 and 1100 is clear for the field technician thanks to what has been described above and is, in particular, as follows.

[0078] Assume that a user wishes to refuel a tank by using the dispenser 100 or 1100. As previously set forth, the tank can be a tank aboard a tanker, a storage tank fixed on the ground or a tank of an engine of a vehicle, such as for example a heavy vehicle or a motor vehicle. First, the user sets a volumetric quantity of diesel fuel to be dispensed by acting on the explosion-proof keypad 22 of the diesel fuel.

[0079] Next, the user pulls out the nozzle 16, 116 for dispensing diesel fuel from the respective housing 18, connects the nozzle 16, 116 for dispensing diesel fuel to the tank and operates the start / stop lever, or the ON-OFF button, 20 for the diesel fuel, thereby activating the pump for supplying diesel fuel (not shown) and dispensing, through the dispensing nozzle 16, 116, the previously set volumetric quantity of diesel fuel.

[0080] When diesel fuel dispensing is complete, the user disconnects the nozzle 16, 116 for dispensing diesel fuel from the tank and places it into the housing 18, 118.

[0081] At this point, the user sets a volumetric quantity of LPG to be dispensed by acting on the explosion-proof keypad 21 of LPG.

[0082] Next, he / she pulls out the nozzle 15, 115 for dispensing LPG from the respective housing 17, 117, connects the nozzle 15, 115 for dispensing LPG to the same tank and operates the start / stop lever, or the ON-OFF button, 19 for LPG, thereby activating the pump for supplying LPG fuel (not shown) and dispensing, through the dispensing nozzle 15, 115, the previously set volumetric quantity of LPG.

[0083] Alternatively to presetting the volumetric quantity of diesel fuel and LPG to be dispensed, the user can personally control the sequential dispensing of diesel fuel, and then of LPG, manually and stop dispensing when the desired volumetric quantity is reached, as currently occurs at all self-service refueling points (not provided with a preset function).

[0084] With reference to figure 3, a dispenser for dispensing an LPG-based fuel for endothermic Diesel-cycle engines according to a second embodiment of the present invention is illustrated therein.

[0085] The dispenser, generally denoted by the number of reference 2100, comprises a containing body or cabinet 10 which includes a lower portion 11 in which a hydraulic circuit CIp for dispensing LPG and a hydraulic circuit Cis for dispensing diesel fuel are housed.

[0086] Similarly to the dispenser 100 described above with reference to figure 1, the dispenser 2100 is adapted for being used in dispensing LPG-based fuel at gas stations, in depots of fuel retailers or in fuel depots of diesel fuel users who, for environmental and / or economic reasons, wish to use the LPG-based fuel, in particular, fuel depots located at fleets of heavy vehicles, buses, locomotives, recreational boats or electricity generating sets in which systems for storing and dispensing diesel fuel intended for supplying engines are already present and / or where systems for manipulating LPG and the LPG-based fuel obtained therefrom are or will be installed.

[0087] The dispenser 2100 further comprises a hose 13 for dispensing LPG and a hose 14 for dispensing diesel fuel. The hose 13 has an end connected to the hydraulic circuit CIp for dispensing LPG and a nozzle 215 for dispensing LPG is mounted at the other end. The hose 14 has an end connected to the hydraulic circuit Cis for dispensing diesel fuel and a nozzle 216 for dispensing diesel fuel is mounted at the other end. The nozzles 215 and 216 are of the high-flow rate type and have zero leakage upon disconnection from a tank (not shown) into which diesel fuel and LPG are supplied and, thanks to their intrinsic characteristics, they naturally self-mix, so as to obtain a chemically and physically stable LPG-based fuel, as defined above.

[0088] A housing 17 for the nozzle 215 for dispensing LPG and a housing 18 for the nozzle 216 for dispensing diesel fuel protrude from the upper portion 12 of the cabinet 10. Moreover, respective start / stop levers, or on-off buttons, 19 and 20 of a pump (not shown) for supplying LPG and a pump (not shown) for supplying diesel fuel extend always from the upper portion, preferably below the housing 17 and the housing 18, respectively.

[0089] Explosion-proof keypads 21 and 22 for presetting the volumetric quantity or amount of LPG-based fuel to be dispensed and electronic metering heads 223, 224, respectively for LPG and diesel fuel, are further present in the upper portion 12 of the cabinet 10.

[0090] In particular, the metering head 223 for LPG comprises a display 225 for displaying the amount of LPG dispensed, a display 227 for displaying the volumetric quantity of LPG dispensed and a display 229 for displaying the LPG price per dispensed unit. Similarly, the metering head 224 for diesel fuel comprises a display 226 for displaying the amount of diesel fuel dispensed, a display 228 for displaying the volumetric quantity of diesel fuel dispensed and a display 230 for displaying the diesel fuel price per dispensed unit.

[0091] When dispensing LPG and diesel fuel, lights to assist the user are further placed in the upper portion 12 of the cabinet 10. In particular, a red light 231 and a green light 233 for LPG and a red light 232 and a green light 234 for diesel fuel are provided. Moreover, there are acoustic signalling devices, in particular an acoustic signalling device 235 for LPG and an acoustic signalling device 236 for diesel fuel. The function of the lights and acoustic signalling devices will become clearer in the following part of the present description.

[0092] The dispenser 2100 is provided with a vehicle recognition system, which comprises an RFID reader 30 preferably fixed at the upper portion 12 of the cabinet 10 of the dispenser 2100 and in electrical communication with the metering heads 223 and 224. The RFID reader 30 is further configured for communicating with a computing unit 32 (visible in figure 5) and with an RFID transponder 31 owned by a user, in which data relating to the engine, vehicle, tank volume, driver, fuel price codes and the like are stored.

[0093] In addition to reading the data relating to the engine / vehicle / tank volume / driver from the RFID transponder 31, the vehicle recognition system is further configured for applying a specific price of diesel fuel and LPG dispensed, different for each individual customer, while also performing administrative checks concerning the ownership of the vehicle, the presence of any dispensing restrictions due to overdue payment, and similar checks.

[0094] As schematically shown in figure 5, which illustrates a functional block diagram of the vehicle recognition system, the RFID transponder 31 transmits data relating to a vehicle V to be refueled with LPG-based fuel to the RFID reader 30 of the dispenser 2100, for example data relating to the volume of the tank of the vehicle V and the mixing percentage of diesel fuel and LPG. The RFID reader 30 transmits the data received from the computing unit 32, which performs a comparison with data in a database 33.

[0095] If the information read does not match that in the database 33, the computing unit 32 denies consent to dispensing and drives the red lights 231 and 232, respectively of LPG and diesel fuel, to switch on. Otherwise, i.e., if the information read matches that in the database 33, the computing unit 32, after having checked that the fuel quantity can be stored inside the tank of the vehicle V, drives the green light 234 on the diesel fuel side and the red light 231 on the LPG side to switch on, and starts dispensing according to the method that will be described in detail hereunder.

[0096] Referring again to figure 3, the vehicle recognition system of the dispenser 2100 further comprises a sensor 217 positioned at the nozzle 215 for dispensing LPG and a sensor 218 positioned at the nozzle 216 for dispensing diesel fuel. The sensors 217 and 218 are configured for real-time reading information relating to the level of fuel present in the tank of a vehicle and sending it to the computing unit 32.

[0097] A tank, configured for cooperate with the sensors 217 and 218 of the nozzles 215 and 216 for respectively dispensing LPG and diesel fuel, is illustrated in figures 7 and 8.

[0098] The tank, generally denoted by the number of reference 40, comprises a metal casing 41 which is made of welded and painted steel or stainless steel of increasing sizes, up to a maximum volume of 1200 liters. The tank 40 is further certified in accordance with the ECE / UN R67 / 01 regulation.

[0099] The tank 40 is provided with a safety valve 42 and a level indicator 43, preferably of the magnetostrictive technology, is fixed therein. The level indicator 43 is preferably provided with a safety sensor 44, for example of the Reed switch type, having the double safety function (redundancy) to block the flow of fuel entering the tank 40.

[0100] The tank 40 further comprises a fuel pickup tube 45, a connection 46 for the fuel return from the engine, a fuel loading connection 47 for the connection to the nozzles 215 and 216 for dispensing LPG and diesel fuel, a non-return valve 48 and a valve 49 for shutting off the loading flow. For passenger cars, the tank 40 is mainly of toroidal type. With reference to figure 4, a dispenser for dispensing LPG-based fuel according to a variant of the dispenser 2100 described above and illustrated with reference to figures 3 and 5, is illustrated therein.

[0101] This dispenser, generally denoted by the number of reference 3100, is adapted for use in gas stations, in fuel depots of users who wish to use LPG-based fuel, in particular for refueling cars, and differs from the dispenser 2100 for the different type of nozzles for dispensing LPG and diesel fuel.

[0102] The dispenser 3100 therefore comprises a containing body or cabinet 10 which includes a lower portion 11 in which a hydraulic circuit CIp for dispensing LPG and a hydraulic circuit Cis for dispensing diesel fuel are housed.

[0103] The dispenser 3100 further comprises a hose 13 for dispensing LPG and a hose 14 for dispensing diesel fuel. The hose 13 has an end connected to the hydraulic circuit CIp for dispensing LPG and a nozzle 315 for dispensing LPG is mounted at the other end. The hose 14 has an end connected to the hydraulic circuit Cis for dispensing diesel fuel and a nozzle 316 for dispensing diesel fuel is mounted at the other end. The nozzles 315 and 316 are of the low-flow rate type and supply the tank inside which diesel fuel and LPG naturally and permanently self-mix, thanks to their intrinsic characteristics, so as to obtain a chemically and physically stable LPG-based fuel, as defined above. The tank has the same characteristics as the tanks of the known type used in the conversion of Otto cycle engines to LPG and will therefore not be described in detail herein.

[0104] A housing 117 for the nozzle 315 for dispensing LPG and a housing 118 for the nozzle 316 for dispensing diesel fuel extend from the upper portion 12 of the cabinet 10. Moreover, respective start / stop levers, or ON-OFF buttons, 19 and 20 of a pump (not shown) for supplying LPG and a pump for supplying diesel fuel extend always from the upper portion, preferably below the housing 117 and the housing 118, respectively.

[0105] Explosion-proof keypads 21 and 22 for presetting the volumetric quantity of LPG-based fuel and also the volumetric quantity of LPG to be dispensed, in the case of refueling cars converted to LPG, and electronic metering heads 223, 224 respectively for LPG and diesel fuel, are further present in the upper portion 12 of the cabinet 10.

[0106] The metering heads 223 and 224 are equal to those described above with reference to the dispenser 2100, so they will not be further detailed herein.

[0107] A red light 231 and a green light 233 for LPG, a red light 232 and a green light 234 for the diesel fuel, an acoustic signalling device 235 for LPG and an acoustic signalling device 236 for the diesel fuel are further placed in the upper portion 12 of the cabinet 10.

[0108] The dispenser 3100 further comprises a vehicle recognition system which, similarly to what is described above with reference to the dispenser 2100, comprises an RFID reader 30, an RFID transponder 31, a computing unit 32 and a database 33.

[0109] The operation of the dispensers 2100 and 3100 is clear for the field technician thanks to what has been described above and is, in particular, as follows.

[0110] Assume that a user wishes to refuel the tank of the engine of a vehicle, for example a heavy lorry or a motor vehicle, by using the dispenser 2100 or 3100. To this purpose, the user brings his / her RFID transponder 31 close to the RFID reader 30 of the dispenser 2100 or 3100. The RFID reader 30 reads a set of information stored in the RFID transponder 31, in particular information relating to the empty capacity of the tank of the vehicle and to the composition percentage of the LPG-based fuel, emits an acoustic signal or beep and sends a signal to the metering heads 223 and 224 to reset the displays 225, 227, 229 and 226, 228, 230, respectively of LPG and diesel fuel. New values of LPG and diesel fuel price read by the RFID transponder 31 are simultaneously set on the displays 229 and 230. More in particular, when the user types the amount of LPG-based fuel to be dispensed on one of the two explosion-proof keypads 21 or 22, the computing unit 32 transmits the price values of the two fuel components to the metering heads 223 and 224, which reset the previous unit prices on the displays 229 and 230, set the new unit prices on the displays 229 and 230 and, simultaneously, switch on the respective red lights 232 and 231 of the diesel fuel and LPG, which let the operator know that the refueling process has started; the diesel fuel nozzles 216, 316 are simultaneously unlocked from the housings 18 and 118. The operator / user grabs the nozzle and connects it to the fuel filler 47 of the tank 40. It is only at this point that the computing unit 32 can start to run its calculation cycle.

[0111] Once the level signal of the fuel present has been received, the computing unit 32 therefore starts to implement the volume calculations of the two fuel components which must be fed in and checks whether the total refueling volume can be received by the free volume in the tank.

[0112] If so, the switching off of the red light 232 of the diesel fuel and the switching on of the green light 234 of the diesel fuel are driven and the acoustic signalling device 236 is triggered, the latter warns the operator / user that he / she must give consent to the diesel fuel pump by operating the start-stop lever or on-off button 20 to start dispensing diesel fuel.

[0113] As soon as the diesel fuel pump starts, the red light 232 of the diesel fuel switches off and the green light 234 of the diesel fuel switches from steady to flashing, so the diesel fuel dispensing starts. Once the programmed quantity of diesel fuel has been dispensed, the metering head 224 stops the dispensing of the diesel fuel, the pump and green flashing light are switched off and the red light 232 of the diesel fuel is switched on.

[0114] The operator disconnects the nozzle 216, 316 of the diesel fuel and places it back into its housing 18, 118. When refueling the diesel fuel, the red light 231 of LPG always stays on. As soon as the nozzle is put back into its housing, the latter is locked, the green light 233 of LPG is switched on, the nozzle housing 17, 117 is controlled to release the nozzle 215, 315 of LPG which the operator / user connects to the same fuel filler 47 of the tank 40. By the sensor 217, 317, the computing unit 32 takes charge of the fuel level in the tank 40, checks again the availability of free volume in the tank for the programmed quantity and, if so, the red light 231 of LPG is switched off and the steady green light 233 of LPG is switched on, the acoustic signalling device 235 of LPG is operated, the operator / user operates the start-stop lever, or on-off button 19 of LPG and, as soon as the pump starts dispensing, the green light 233 of LPG switches from steady to flashing. During the refueling step, the red light 232 of the diesel fuel stays on. When the programmed quantity of LPG has been dispensed, the head 223 switches off the LPG dispensing pump, switches off the flashing green light 233 and switch on the red light 231 of LPG. The operator disconnects the nozzle 215, 315 of LPG and placed it back into the housing 17, 117, which locks the nozzle. All the lights are switched off and the refueling is finished. At this point, a signal is sent to the information system, which will start the administrative invoicing procedure, or the user pays at the cash desk.

[0115] In case there are no administrative restrictions and once the volume check has been carried out, if the computing unit 32 switches on the red light 232 for the diesel fuel, it means that the quantity required is not compatible with the volume available inside the tank 40. In this case, the user must set and continue to reset a new lower quantity on one of the two explosion-proof keypads 21 and 22, until the green light 234 for the diesel fuel switches on. At this point, the process can start as described above. The Reed Switch technology sensor of the tank 40 is used as a second safety (redundancy) which blocks the loading flow of the diesel fuel if it exceeds the maximum level allowed by current safety regulations (<80% o <85%).

[0116] For user with less spending capacity, the process described above is limited to reading the volume of the installed tank and to the mixing percentage, which were stored on the transponder 31. Administrative checks are not carried out and refueling is enabled.

[0117] A kit for dispensing LPG-based fuel, which can be installed on all dispensers of the known type being used at gas stations where LPG and diesel fuel are dispensed, was designed to allow dispensing the LPG-based fuel at all refueling points. In particular, the dispensers of the known type have dual hydraulics, one of which will be connected to the diesel fuel tubes to be able to dispense the diesel fuel and the other hydraulics will be connected to the LPG tubes for dispensing LPG.

[0118] A kit for dispensing LPG-based fuel according to the present invention, generally denoted by the number of reference 50, is shown in figure 6.

[0119] The dispensing kit 50 comprises an RFID reader 30 combined with a computing unit 32, which includes firmware for controlling and managing the dispensing method of the LPG-based fuel, the communication protocol with metering heads 223 and 224 of the dispenser, for LPG and diesel fuel, also for changing the price of the diesel fuel and LPG to be dispensed and sending information to the company selling the LPG-based fuel, a green light 234, red light 232 and acoustic signalling device 236 set for the diesel fuel and a green light 233, red light 231 and acoustic signalling device 235 set for LPG.

[0120] The kit 50 further comprises two dispensing tubes 13 and 14 each provided with a respective high-flow rate dispensing nozzle 215 and 216 and a sensor 217, 218 with a Wi-Fi connection device, and two dispensing tubes 13 and 14 each provided with a respective low-flow rate dispensing nozzle 315 and 316 and a sensor 317, 318 with a Wi-Fi connection device. The kit 50 comprises a set of signal cables in case you prefer not to use the Wi-Fi connection.

[0121] Of course, although four dispensing nozzles are illustrated in figure 6, it is possible to also provide only two low-flow rate dispensing nozzles 315 and 316 or two high-flow rate dispensing nozzles 215 and 216.

[0122] Once the necessary mechanical, hydraulic and electrical connections have been made, the dispensing kit 50 enables a user to dispense the LPG-based fuel in the desired compositions and quantities. The key information (tank volume and percentage composition) is stored on the RFID transponder 31 and the method of dispensing the LPG-based fuel is the same as that described above, since the vehicles, coming for refueling, have the magnetostrictive technology level indicator 43 already installed inside the thank.

[0123] As known, an endothermic Diesel-cycle engine has, during its operation, a return flow of fuel that has not been used. The flow rate of this flow is given by the difference, by subtraction, between the constant flow rate of the pump supplying diesel fuel to the engine and the consumption of the engine itself in its various loading steps. The fuel, having come into contact with the very hot parts of the engine, heats up.

[0124] When the Diesel-cycle engine is supplied with an LPG-based fuel, a pressure increase due to the expansion of LPG is generated in the fuel return circuit, as a result of the temperature increase. To avoid this pressure raise, it is necessary to prevent the expansion of LPG present in the fuel lines.

[0125] This is achieved by providing a device for cooling the hot fuel. Cold decreases the volume of LPG contained and will consequently also decrease the pressure in the fuel lines. Moreover, a “colder” combustion has an improved impact on the quality and type of emissions.

[0126] Such a cooling device is schematically shown in figures 9 and 10 and consists in a cooling tank 60, which is positioned between the tank of a heavy vehicle or car, for example the tank 40 described above and illustrated in figures 7 and 8, and an engine M and in fluid communication with them.

[0127] As shown in detail in figure 9, a cooling coil 61, a level switch 62 and one or more pressure and temperature sensors (not shown in figures 9 and 10) are inside the cooling tank 60. The cooling tank 60 further comprises an inlet connection 63 of coolant, an outlet connection 64 of coolant, an inlet connection 65 of a hot LPG-based fuel coming from the engine M, a connection 66 of the ambient temperature LPG- based fuel coming from the tank 40 and an outlet connection 68 of the cold LPG-based fuel, towards the engine M.

[0128] In use, the LPG-based fuel present in the tank 40 is channeled, by means of a pump (not shown) inside or outside of the tank, into the cooling tank 60.

[0129] The LPG-based fuel comes into contact with the cooling coil 61 inside the cooling tank 60, therefore cooling itself. The level switch 62 and the pressure and temperature sensors ensure the inflow, permanence and outflow of the LPG-based fuel from the cooling tank 60, in order to ensure the proper flow of LPG-based fuel to the engine M.

[0130] Preferably, before being channeled into the cooling tank 60, the hot LPG-based fuel returning from the engine M undergoes first desuperheating through an additional heat exchanger (not shown), whose exchange flow is the coolant coming from a specific cooling unit, in the case of supplying heavy-duty engine, or coming from the air-conditioning systems, in the case of cars.

[0131] LPG-based fuel, maintained at a temperature of 2°C, prevents the development of abnormal pressures which the original sensors on the fuel circuit of the engine would certainly detect.

[0132] Thanks to the present invention, it is possible to have a dispenser and a method of dispensing LPG-based fuel, such that an LPG-based fuel can be dispensed with a variable LPG content depending on the type of vehicle to be refueled. Moreover, the dispenser and the method of dispensing LPG-based fuel for endothermic Diesel-cycle engines according to the invention are such as to supply all Diesel-cycle engines used in the many types and applications of wheeled land transportation, in power plants, on locomotives, in marine recreational boats, on earth-moving machinery and agricultural tractors. Still, the dispenser for dispensing fuel for endothermic Diesel-cycle engines is such that it can be made within competitive times and costs. Finally, the dispenser and the method of dispensing a fuel for endothermic Diesel-cycle engines according to the present invention can be made / obtained wherever LPG and diesel fuel and / or its homologues are available. Various modifications may be made to the embodiments described in detail, all anyhow remaining within the scope of protection of the invention, as defined by the following claims.

Claims

CLAIMS1. Dispenser (100; 1100; 2100,3100) for dispensing an LPG-based fuel for endothermic Diesel-cycle engines, characterized by comprising:- a hydraulic circuit (CIp) for supplying a primary component of the LPG- based fuel, wherein the primary component is constituted by LPG;- a hydraulic circuit (CIp) for supplying a secondary component of the LPG- based fuel, wherein the secondary component is constituted by diesel fuel or its homologues;- a hose for dispensing the primary component (13), which has an end connected to the hydraulic circuit (CIp) for supplying the primary component and the other end provided with a nozzle (15; 115; 215; 315) for dispensing the primary component;- a hose for dispensing the secondary component (14) which has an end connected to the hydraulic circuit (Cis) for supplying the secondary component and the other end provided with a nozzle (16; 116; 216; 316) for dispensing the secondary component; wherein said nozzle (16; 116; 216; 316) for dispensing the secondary component and said nozzle (15; 115; 215; 315) for dispensing the primary component are operable in sequence for dispensing a predetermined volumetric quantity of said secondary component and a predetermined volumetric quantity of said primary component, so as to obtain an LPG-based fuel which has an LPG content ranging between at least 51% and 80%, limits included.

2. Dispenser (100; 1100; 2100; 3100) according to claim 1, further comprising explosion-proof keypads (21; 22) for respectively presetting a volumetric quantity or an amount of the primary component of the LPG-based fuel to be dispensed and a volumetric quantity or an amount of the secondary component of the LPG-based fuel to be dispensed and start / stop levers, or ON-OFF buttons, (19; 20) of the hydraulic circuits (CIp; Cis) for supplying the primary component and the secondary component.

3. Dispenser (100; 1100) according to claim 1 or 2, further comprisingvolumetric electronic heads (23, 24) for the primary and secondary components and displays (25, 26) for displaying the dispensed volumetric quantity of the primary component and secondary component.

4. Dispenser (2100; 3100) according to claim 1 or 2, further comprising electronic metering heads (223, 224) respectively for the primary component and the secondary component of the LPG-based fuel, each comprising a display (225, 226) for displaying the amount of the respective component dispensed, a display (227, 228) for displaying the volumetric quantity of the respective component dispensed, and a display (229, 230) for displaying the price per dispensed unit of the respective component dispensed.

5. Dispenser (2100,3100) according to claim 4, comprising, for the primary and secondary components of the LPG-based fuel, a red light (231, 232), a green light (233, 234) and an acoustic signalling device (235, 236).

6. Dispenser (2100; 3100) according to claim 4 or 5, further comprising a vehicle recognition system which comprises an RFID reader (30) fixed on a containing body (10) of the dispenser and in electrical communication with said metering heads (223, 224), wherein said RFID reader (30) is configured for communicating with an RFID transponder (31) of a user of a vehicle (V) to be refueled with the LPG-based fuel and with a computing unit (32) of the dispenser, and wherein data relating to the vehicle, the engine of the vehicle and / or the user of the vehicle is stored in said RFID transponder (31).

7. Dispenser (2100; 3100) according to claim 6, wherein said vehicle recognition system further comprises a sensor (217; 317) positioned at the nozzle (215; 315) for dispensing the primary component of the LPG-based fuel and a sensor (218; 318) positioned at the nozzle (216; 316) for dispensing the secondary component of the LPG-based fuel, wherein said sensors (217; 317, 218; 318) are configured for reading real-time information relating to the level of fuel present in the tank (40) of a vehicle (V) and sending it to the computing unit (32).

8. Kit (50) for dispensing an LPG-based fuel for endothermic Diesel-cycle engines, characterized by comprising:- an RFID reader (30) combined with, and in communication with, a computing unit (32);- an RFID transponder (31);- at least one pair of dispensing tubes (13, 14), each provided with a respective dispensing nozzle (215, 216; 317, 318) provided with a sensor (217, 218; 317, 318), a tube (13) being intended for dispensing a primary component of the LPG-based fuel and the other tube (14) being intended for dispensing a secondary component of the LPG-based fuel; and- a pair of green light (233, 234) - red light (231, 232) - acoustic signalling device (235, 236) sets, a set (233, 231, 235) being combined with the primary component of the LPG-based fuel and the other set (234, 232, 236) being combined with the secondary component of the LPG-based fuel.

9. Tank (40) for use with a dispenser (100; 1100; 2100; 3100) according to claim 7, characterized by comprising, inside it, a level indicator (43) preferably of the magnetostrictive technology type, wherein the level indicator (43) is adapted for cooperating with said sensor (217; 317) positioned at the nozzle (215; 315) for dispensing the primary component of the LPG-based fuel and with said sensor (218; 318) positioned at the nozzle (216; 316) for dispensing the secondary component of the LPG-based fuel.

10. Tank (40) according to claim 9, further comprising a safety sensor (44) configured for blocking the flow, inside the tank, of the secondary component and the primary component of the LPG-based fuel.

11. Cooling device (60) for use with a tank (40) according to claims 9 and 10, characterized by comprising:- a cooling coil (61);- an inlet connection (63) and an outlet connection (64) of coolant;- an inlet connection (65) of a hot LPG-based fuel coming from an engine (M) of a vehicle (V); and- an inlet connection (66) of an ambient temperature LPG-based fuel coming from the tank (40) and an outlet connection (68) of the cold LPG-based fuel, towardsthe engine (M).

12. Method for dispensing an LPG-based fuel for endothermic Diesel-cycle engines, performed by using a dispenser (100; 1100; 2100; 3100) according to any one of claims 1 to 7, the method comprising the following steps performed in sequence:- dispensing, into a tank (40), a volumetric quantity of a secondary component of the LPG-based fuel;- dispensing, into the same tank (40), a volumetric quantity of a primary component of the fuel; and- self-mixing, inside the tank (40), the primary and secondary components, so as to obtain the LPG-based fuel which has an LPG content ranging between at least 51% and 80%, limits included.

13. Method according to claim 12, when dependent on claim 6, comprising, upstream of the dispensing steps, a step of recognizing vehicles, comprising the following steps:- transmitting, from an RFID transponder (31) to an RFID reader (30), data relating to a vehicle (V) to be refueled with the LPG-based fuel;- transmitting, from the RFID reader (30) to a computing unit (32), the data received;- comparing, by the computing unit (32), the data received with data in a database (33);- if the information received does not match that in the database (33), denying consent, by the computing unit (32), to dispense and switching on the red lights (231, 232), respectively of the primary component and the secondary component of the LPG-based fuel;- if the information received matches that in the database 33, switching on, by the computing unit (32), the green lights (233, 234), respectively of the primary and secondary components of the LPG-based fuel, and starting dispensing.

14. Method according to claim 12, when dependent on claim 6, wherein the tank is a tank (40) according to claim 9 and said step of dispensing the secondary component into the tank (40) comprises the following steps carried out by thecomputing unit (32):- calculating the volume occupied by the secondary component of the LPG- based fuel, parameterizing it to the unit price and the value set by a user;- adding, to this calculated volume, the volume that will be occupied by the primary component, again parameterizing it to the price read;- checking whether the space available inside the tank (40) can receive the refueling volume required, and if the total refueling volume cannot be stored inside the tank (40), denying consent to dispense, keeping the red light 232 for the diesel fuel on; if the total refueling volume can be stored inside the tank (40), allowing consent to dispense, until reaching the programmed dispensing volume.

15. Method according to claim 14, wherein, during said step of dispensing the primary component into the tank (40), the computing unit (32) checks in real time that the increase in fuel level inside the tank remains within the calculated limits.

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