WO1998023530A1

WO1998023530A1 - Device for injecting liquid additive into a fuel

Info

Publication number: WO1998023530A1
Application number: PCT/FR1997/002162
Authority: WO
Inventors: Bernard Audic; Arnaud De Ferry
Original assignee: Schlumberger Industries
Priority date: 1996-11-28
Filing date: 1997-11-28
Publication date: 1998-06-04
Also published as: FR2756268B1; FR2756268A1; EP0942894A1

Abstract

The invention concerns a device for injecting a liquid additive while a fuel is being dispensed through a dispensing line comprising a pumping set (10), a flow meter (11) for the fuel delivery, a flexible pipe (14) provided with a dispensing pistol (15), said meter (11) being capable of supplying to a computer (20) a signal representing the flow rate of fuel delivered. The invention is characterised in that the injecting device comprises a tank (30) of additive liquid, a pump (33) for sucking in said additive liquid, a motor (35) for driving said suction pump (33) and a flow conduit (34) for bringing the additive liquid up to the fuel dispensing pistol (15), said computer (20) being capable of delivering to said driving motor (35) a control signal such that the flow rate of the liquid additive sucked in, throughout the dispensing, remains proportional, in a predetermined constant ratio, to the flow rate of supplied fuel. The invention is applicable to the dispensing of fuel.

Description

DEVICE FOR INJECTING LIQUID ADDITIVE INTO FUEL

The present invention relates to a device for injecting a liquid additive during the dispensing of a fuel. In general, the fuel distributors found in service stations include a distribution line made up of a certain number of members, namely, in order, a pumping assembly intended to suck fuel from a storage tank, a fuel flow meter circulated by the pumping assembly and a flexible lance equipped with a dispensing gun actuated by the user to fill the tank of his vehicle.

Next to this purely hydraulic distribution line, the distributors have an electronic chain including the flow meter, which is provided with means, such as a coding wheel, capable of providing a signal representative of the flow of the fuel delivered, generally a train. of pulses of which each pulse represents a given volume, 1 cl for example. This flow signal is transmitted to a computer which establishes, during the distribution, the volume of fuel delivered and the amount to be paid, to the destination, on the one hand, of a display present on the distributor and, on the other part of the service station management system.

On the other hand, oil companies are increasingly offering their customers additive products today in addition to their fuel in order, for example, to improve engine lubrication or fuel combustion.

The currently known means for adding an additive to a fuel consist in either pouring the additive directly into the vehicle tank from, for example, a can sold separately, or to carry out the addition further upstream during the manufacture of the fuel in a refinery.

However, none of these methods is completely satisfactory because they require a tedious and imprecise and reproducible manual addition operation, or that they offer no possibility of choice to the user as to the presence or no additive and as to its proportions.

Also, the technical problem to be solved by the object of the present invention is to provide a device for injecting a liquid additive during the distribution of a fuel through a distribution line comprising a pumping assembly , a fuel flow meter, a flexible lance equipped with a dispensing gun, said meter being capable of supplying a computer with a signal representative of the flow of fuel delivered, a device which would make it possible to remedy the drawbacks of known addition methods of the state of the art, in particular by carrying out the injection at the level of the dispenser itself.

The solution to the technical problem posed consists, according to the present invention, in that said injection device comprises a reservoir of liquid additive, a suction pump of said liquid additive, a motor for driving said suction pump and a circulation conduit intended to bring the liquid additive to the dispensing gun, said injection device being able to establish, from said representative flow rate signal, and to apply to said drive motor a control signal such as the flow rate of liquid additive aspirated remains, throughout the distribution, proportional, in a given constant ratio, to the flow rate of fuel delivered. Thus, the device of the invention performs an automatic addition of additive without requiring manual operation subsequent to the distribution or prior mixing. On the other hand, it can be noted that the precision as to the concentration of the liquid additive is perfectly guaranteed whatever the fuel delivery rate imposed by the user by his action on the gun.

According to a particular embodiment of the injection device of the invention, said device comprises a concentration selector, connected to said computer. It is thus possible for the user to choose, when he decides to fill the tank of his vehicle, if he wishes to add liquid additive to the fuel and in what proportion, knowing that the proportion chosen at the start will be maintained constant during fuel distribution.

In general, the injection device of the invention will be integrated with the distribution line inside a single device, namely the fuel distributor, this integration being carried out at the time of manufacture of the distributor. . In this case, the drive motor control signal is established by the computer itself from the signal received from the flow meter.

However, for existing fuel distributors, not equipped with an additive injection device, the integration of such a device can present real difficulties, due to the size, the security, the diversity of distributor brands, etc ... This is why the invention provides that the injection device comprises a control module connected to the computer, to the injection device, to a management unit, and to the concentration selector, and able to:

- send concentration selection information from said concentration selector to the computer,

- receive information from the dispensing unit off the computer in order to deactivate the concentration selector,

- receive from the computer hanging information from the distribution gun in order to put the concentration selector back into service, - receive from the computer the signal supplied by the fuel flow meter,

- establish and apply said control signal to the engine of the injection device,

- receive at least low additive level information in the reservoir, coming from the low level detection device,

- send said low level information to said management unit.

Thus, the injection device is presented as an independent modular assembly external to the distributor itself. It is easily adaptable to any type of distributor, without appreciable modification of the latter. To do this, simply connect the computer to the control module and the additive circulation pipe to the fuel distribution line. According to the invention, said low additive level information comes from a low level detection device capable of detecting, on the one hand, a first low level of indication of replacement of the liquid additive reservoir, and , on the other hand, a second low level, lower than the first, of decommissioning of the liquid additive injection device.

The description which follows with reference to the appended drawings, given by way of nonlimiting examples, will make it clear what the invention consists of and how it can be implemented.

FIG. 1 is a diagram of a fuel dispenser comprising a liquid additive device according to the invention.

Figure 2a is a sectional view of a first embodiment of a flexible lance of the dispenser of Figure 1. Figure 2b is a sectional view of a second embodiment of a flexible lance of the dispenser Figure 1.

FIG. 3 is a diagram of a device for visualizing the circulation of liquid additive in the dispenser of FIG. 1.

FIG. 4 is a diagram of an alternative embodiment of the dispenser of FIG. 1.

In Figure 1 is shown the distribution line of a fuel distributor, comprising a pumping assembly 10 for sucking fuel from a storage tank 1. This pumping assembly 10 consists, in a conventional manner, of a pump, which can be submerged, of an air separator, of a pressure regulator and of a filtering unit.

The fuel thus sucked is forced to a meter 1 1 of fuel flow. This device makes it possible to produce, under the action of the movement of fuel, a rotational movement of an axis whose angular speed is proportional to the flow of the fuel. To obtain an electrical signal representative of the fuel flow, it suffices to place a coding wheel, for example, on the axis of the meter. Said coding wheel can be an optical disc pierced with equidistant peripheral slots arranged on the path light between a light source and a detector. The signal supplied by the counter 1 1 is then a train of pulses, each pulse equivalent to a certain volume of fuel, 1 cl for example, according to the calibration. This electrical signal is transmitted to a computer 20 which, after processing, permanently establishes the volume of fuel delivered and the amount to be paid, taking account of the unit price. These indications are provided to a display 21 present on the dispenser for viewing intended for the user. Downstream of the flow meter 1 1, the distribution line is continued by a fixed metal pipe 12 to a part 13 for connection to a flexible lance 14 terminated by a dispensing gun 15. Of course, the flexible lance and the dispensing gun can be equipped with means for recovering the vapors escaping from the vehicle tank during dispensing.

In accordance with the invention, the dispenser of FIG. 1 is provided with a device for injecting liquid additive comprising a reservoir 30 of liquid additive which can be a packaging container supplied by the petroleum company manufacturer and changed by the service station manager.

Said reservoir 30 is connected to a suction pump 33 by means of a tube 31 plunging into the additive and passing through a screwed cap 32. The suction pump 33 is preferably a volume pump, of the gear, vane type, with one or more pistons, perilstatic, etc. , so as to perform two functions at the same time, namely pressurizing the additive and controlling its dosage in the fuel. At the outlet of the suction pump 33, the liquid additive is directed towards the dispensing gun 15 through a circulation duct 34 comprising a proximal metal part 34a fixed between the pump 33 and the connecting piece 13, and a distal part 34b which, in general, takes the form of a flexible pipe associated with the flexible lance 14.

In the embodiment of FIG. 2a, said flexible pipe 34b is an independent tube placed inside the flexible lance 14. In the variant of FIG. 2b, the distal part 34b of the circulation duct is integrated, by molding for example, with flexible lance 14.

The mixing of the liquid additive with the fuel therefore takes place at the level of the dispensing gun 15. Preferably, the liquid additive is injected by the pump 33 under a pressure higher than that of the fuel, the distal part 34b of the pipe 34 opening into the gun 15 by a calibrated non-return valve, not shown, preventing the additive to escape between two distributions and the return of fuel to the tank 30. As shown in Figure 1, the suction pump 33 is driven by a motor 35 itself controlled by a control signal established by the computer 20 as a function, on the one hand, of the desired concentration for the additive and, on the other hand, of the fuel flow rate, with the aim of ensuring a constant flow rate ratio whatever the flow rate imposed by the user .

In the case where the signal representative of the fuel flow rate is a pulse train, as previously described, and if the desired concentration is x% o for example, the computer 20 will produce, as a control signal, a pulse every 1000 / x pulses received from counter 1 1.

The drive motor 35 can be of any type: electric, pneumatic, etc. , whose rotation is controlled by pulses such as stepper motors or DC motors associated with a rotation encoder.

In order to allow the user to choose the dosage of additive that suits him, the injection device comprises a concentration selector 36, connected to the computer 20, by predetermined values (0.50%, 100%) or by continued. Naturally, the computer in this case comprises means for calculating the unit price of added fuel, which depends on the concentration of additive chosen.

Finally, provision can be made for the reservoir 30 of liquid additive to be equipped with a device for detecting at least a low level of the additive. The device shown in FIG. 4 makes it possible to detect a first low level N I in order to warn the manager of the service station in good time of the need to replace the tank with a full tank. A second low level N2, lower than N I, can also be detected in order to deactivate the additive injection device, in the event that the reservoir 30 has not been replaced after detection of the level N I.

Likewise, in accordance with FIG. 3, a device 37 for visualizing the circulation of liquid additive (transparent member provided with a fin, flap, etc.) can be placed in the proximal part 34a of the circulation duct.

Of course, several injection devices can exist in the same fuel dispenser. In this case, the distal parts of the various circulation conduits are introduced into the same flexible lance, that of the distributor. Similarly, in the case of a multi-product fuel dispenser, it may be advantageous to use the same suction pump to inject the additive into several guns. Under these conditions, solenoid valves make it possible to select the flexible lance which must be supplied, this information being known to the computer.

The injection device according to the invention can also be of particular interest for reconstituting a leaded fuel by adding a liquid heavily loaded with lead. This could be a solution to eliminate the distribution of leaded fuel, the use of which is decreasing sharply due to the generalization of unleaded fuel, and nevertheless satisfy the users of old vehicles, collection vehicles and others: lawn mowers , boat engines. For the latter category, the additive could be special marine engine oil or 2-stroke engine oil.

Figure 4 shows a variant of the fuel dispenser of Figure 1, in which the liquid injection device, instead of being integrated into the dispenser, forms an independent assembly, placed outside the dispenser.

According to this variant, a control module 100 is connected to the concentration selector 36, to the injection device, to the computer 20 and to a service station management unit 101. It will be noted that the installation of this injection assembly is very simple since it only requires the connection of the computer 20 to the control module 100 and the conduit 34 for the circulation of additive to the connecting piece 13. This adaptation operation does not require any significant modification of the distributor and is independent of the type of distributor considered. In operation, the control module 100 sends to the computer 20 a concentration selection information coming from the concentration selector 36, this to allow the computer to establish the amount to be paid according to the concentration (0, 2, 1) d 'additive chosen by the user.

After selecting the concentration, the computer 20 sends information to the control module 100 to detach the gun 15 in order to deactivate the selector 36 during the fuel distribution. Conversely, on hang-up information supplied by the computer 20, the control module 100 sends the selector 36 a return to service signal for the next distribution.

Said control module 100 is also responsible for establishing the control signal and applying it to the drive motor 35 at the injection device, on the basis of the signal supplied by the counter 1 1 also received from the computer. It will be noted that in this variant the control signal is established by the control module 100 and not by the computer 20.

As shown in FIG. 4, the additive injection device comprises a detection device of two levels, namely a first low level NI whose detection is the subject of the module 100 for controlling the sending of information to the management unit 101 in order to warn the manager of the service station that the replacement of the additive reservoir 30 is necessary. A second low level N2, lower than the first, can also be detected, causing the final deactivation of the additive injection device. This event is communicated to the management unit 101 for intervention.

Claims

1. Device for injecting a liquid additive during the distribution of a fuel through a distribution line comprising a pump assembly (10), a fuel flow meter (1 1), a lance flexible (14) equipped with a dispensing gun (15), said counter (1 1) being able to supply a computer (20) with a signal representative of the flow rate of the fuel delivered, characterized in that the injection device comprises a tank (30) of liquid additive, a pump (35) for suction of said liquid additive, a motor (35) for driving said pump (33) for suction and a conduit (34) for circulation intended to bring the liquid additive to the fuel distribution gun (15), said injection device being able to establish, from said representative flow rate signal, and to apply to said drive motor (35) a control signal such that the flow of liquid additive aspirated remains, throughout the dispensing ion, proportional, in a given constant ratio, to the flow of fuel delivered.

2. Device according to claim 1, characterized in that the suction pump (33) is a volume pump.

3. Device according to claim 2, characterized in that said suction pump (33) injects the liquid additive under a pressure greater than the fuel pressure, said circulation pipe (34) opening into the gun (15) distribution by a calibrated non-return valve.

4. Device according to any one of claims 1 to

3, characterized in that said device comprises a concentration selector (36), connected to said computer (20).

5. Device according to claim 4, characterized in that the calculator (20) comprises means for calculating the unit price of fuel added.

6. Device according to any one of claims 1 to 5, characterized in that said conduit (34) for circulation comprises a distal part (34b) in the form of a flexible pipe disposed inside the flexible lance (14 ).

7. Device according to any one of claims 1 to 5, characterized in that said duct (34) for circulation comprises a distal part (34b) integrated into the flexible lance (14).

8. Device according to any one of claims 1 to 7, characterized in that the circulation conduit (34) comprises a device (37) for displaying the circulation of liquid additive.

9. Device according to any one of claims 1 to 8, characterized in that said reservoir (20) comprises a device for detecting at least a low level of liquid additive.

10. Device according to claim 9, characterized in that said low level detection device is capable of detecting, on the one hand, a first low level (NI) of indication of replacement of the reservoir (30) of liquid additive , and on the other hand, a second low level (N2), lower than the first, of deactivation of the liquid additive injection device.

11. Device according to any one of claims 4 to 10, characterized in that it comprises a control module (100) connected to the computer (20), to the injection device, to a management unit (101), and to the concentration selector (36), and able to: - send to the computer (20) concentration selection information coming from said concentration selector (36),

- receiving information from the computer (20) that the dispensing gun (15) has been unhooked in order to deactivate the concentration selector (36), - receive from the computer (20) information on hanging up the dispensing gun (15) in order to put the concentration selector (36) back into service,

- receive from the computer (20) the signal supplied by the fuel flow meter (1 1),

- establishing and applying said control signal to the engine (35) of the injection device,

- receive at least one piece of information (N I, N2) about the low level of additive in the reservoir (30), coming from the low level detection device,

- send to said management unit (101) said low level information.