WO2004080884A2 - System for controlling the vapour recovery of a fuel pump - Google Patents

System for controlling the vapour recovery of a fuel pump Download PDF

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Publication number
WO2004080884A2
WO2004080884A2 PCT/EP2004/002567 EP2004002567W WO2004080884A2 WO 2004080884 A2 WO2004080884 A2 WO 2004080884A2 EP 2004002567 W EP2004002567 W EP 2004002567W WO 2004080884 A2 WO2004080884 A2 WO 2004080884A2
Authority
WO
WIPO (PCT)
Prior art keywords
flow
vapour
pump
sensor
fuel
Prior art date
Application number
PCT/EP2004/002567
Other languages
French (fr)
Other versions
WO2004080884A8 (en
WO2004080884A3 (en
Inventor
Umberto Corti
Christian Tavani
Original Assignee
Nuovo Pignone S.P.A.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nuovo Pignone S.P.A. filed Critical Nuovo Pignone S.P.A.
Publication of WO2004080884A2 publication Critical patent/WO2004080884A2/en
Publication of WO2004080884A8 publication Critical patent/WO2004080884A8/en
Publication of WO2004080884A3 publication Critical patent/WO2004080884A3/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B67—OPENING, CLOSING OR CLEANING BOTTLES, JARS OR SIMILAR CONTAINERS; LIQUID HANDLING
    • B67D—DISPENSING, DELIVERING OR TRANSFERRING LIQUIDS, NOT OTHERWISE PROVIDED FOR
    • B67D7/00—Apparatus or devices for transferring liquids from bulk storage containers or reservoirs into vehicles or into portable containers, e.g. for retail sale purposes
    • B67D7/04—Apparatus or devices for transferring liquids from bulk storage containers or reservoirs into vehicles or into portable containers, e.g. for retail sale purposes for transferring fuels, lubricants or mixed fuels and lubricants
    • B67D7/0476—Vapour recovery systems
    • B67D7/0478—Vapour recovery systems constructional features or components
    • B67D7/048—Vapour flow control means, e.g. valves, pumps
    • B67D7/0482—Vapour flow control means, e.g. valves, pumps using pumps driven at different flow rates
    • B67D7/0486—Pumps driven in response to electric signals indicative of pressure, temperature or liquid flow
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
    • G01F1/20—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow
    • G01F1/22—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow by variable-area meters, e.g. rotameters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
    • G01F1/20—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow
    • G01F1/22—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow by variable-area meters, e.g. rotameters
    • G01F1/24—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow by variable-area meters, e.g. rotameters with magnetic or electric coupling to the indicating device
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
    • G01F1/20—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow
    • G01F1/28—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow by drag-force, e.g. vane type or impact flowmeter

Definitions

  • the present invention relates to a system for controlling the recovery of vapours in fuel pump columns.
  • the present invention relates to a system for controlling the recovery of vapours in fuel pump columns equipped with a device for recovering the vapours discharged during refueling operations of vehicles.
  • vapour phase consisting of a mixture of air and fuel vapours, discharged from vehicle tanks during refueling, are not dispersed in the atmosphere.
  • This emission is essentially due to the effect of the movement on the part of the liquid that is entering the tank, which reduces the volume above its level and expels an equal volume of vapour phase.
  • the known art envisages the suction of this air/vapour phase by equipping the fuel supply guns with both fuel supply nozzles and suction nozzles, connected to volumetric pumps.
  • the supply gun is connected to the column with a conveyance pipe of the liquid fuel fed to a pumping group at a varying flow-rate and with a suction pipe connected to a volumetric vapour suction pump which is activated with a flow-rate strictly correlated, at each instant, with the fuel conveyance flow-rate.
  • the quantity of vapours to be recovered is calculated on the basis of the quantity of fuel supplied by means of characteristic pre-memorized curves in said control unit which connect the volume of vapour recovered from the device with the volume of fuel supplied, a function which, in reality, follows a non-linear trend.
  • the control device regulates the volumetric pump of the vapour recovery on the basis of said curve.
  • the Applicant has observed that by surveying in real time the flow-rate of the vapour recovery line in a fuel pump column, it is possible to almost exactly evaluate the ratio between the fuel supplied and the quantity of vapour to be recovered without having to effect estimates and calculations which can, in some cases, prove to be inaccurate.
  • the Applicant has found that by inserting a flow- rate sensor onto the vapour return line and monitoring in real time the quantity of vapour recovered, it is possible to constantly control the flow-rate of the vapour recovery pump.
  • the Applicant has set up a system for the recovery of vapours in a fuel pump column by means of a magnetic flow-rate sensor.
  • An aspect of the present invention relates to a system for controlling the recovery of vapours in a fuel pump column, said column comprising
  • said system comprises a flow-rate sensor situated on the vapour return line which generates a signal relating to the flow-rate of the vapour recovered and
  • said control unit detects said signal relating to the flow-rate of vapour recovered and controls the suction pump so as to maintain the ratio between the quantity of fuel supplied and the quantity of vapour recovered at a pre-established value.
  • Figure 1 is a schematic representation of a pump column to a supply gun with vapour phase recovery
  • Figure 2 represents a block scheme of an embodiment of the control system for the recovery of vapours, according to the present invention
  • Figures 3a-3c show graphs which illustrate the quantity of fuel supplied from a pump column and the quantity of vapour recovered by means of the control system according to the present invention
  • Figure 4 schematically illustrates a flow-rate sensor, according to the present invention.
  • Figure 1 illustrates a fuel pump column 10 equipped with a box-shaped supporting structure 11 which contains and supports its organs .
  • the fuel is contained in an underground cistern, not shown in the figure, from which the fuel is sent by means of a supply line, which comprises an inlet 12, a pumping group 13 which is connected with a supply gun 18, a meter 14 which measures the quantity of fuel supplied, before sending it, through a duct 15, to a separator 16, from which there is a flexible tube 17 of the supply gun 18.
  • a supply line which comprises an inlet 12, a pumping group 13 which is connected with a supply gun 18, a meter 14 which measures the quantity of fuel supplied, before sending it, through a duct 15, to a separator 16, from which there is a flexible tube 17 of the supply gun 18.
  • An impulse generator 20 is connected to the meter 14, which generates an electric impulse for each unit of fuel supplied, for example for each centiliter; this impulse signal has a frequency which is proportional to the flow-rate and is transmitted to an indicator 21, which, on the basis of the number of impulses, calculates and indicates the quantity supplied and the relative refueling price.
  • the same signal relating to the quantity of fuel supplied is transmitted to an electronic control unit 22.
  • the column also comprises a recovery line of the vapours discharged from the tank of a vehicle during fuel supply.
  • a fuel conveyance duct 23 which is the extension of the conveyance duct 15 to the supply nozzle, and also a return duct 24 connected to a suction nozzle situated close to the supply nozzle.
  • the vapour recovery line comprises said nozzle which sucks the vapours discharged from the tank which is being filled, the return duct 24 which is joined in the separator 16 to a duct 25, a volumetric vapour suction pump 26 connected to said duct 25, which is activated by a motor 27 driven by the electronic control unit 22.
  • the number of revs of said motor is preferably uninterruptedly connected to the frequency of the impulse signal of the generator 20, so as to correlate the revs of the pump 26, and consequently the volumetric suction pump, to the fuel conveyance flow-rate.
  • the emission of the volumetric pump 26 preferably re-enters the underground cistern of the pump, by means of the duct 28, from which the fuel is removed; the volumetric ratio between the fuel supplied and gaseous phase sucked up, is generally established and maintained within a range of values around the unitary value; said fixed value can vary in relation to the type of fuel and environmental conditions.
  • the fuel supply is typically effected with a varying flow-rate and is regulated by the attendant by the pressure exerted on a regulation lever 30 of the gun, whereas the suction flow-rate must constantly follow the course of the conveyance flow-rate.
  • the sequence of impulses faithfully represents the situation, at each instant, of the liquid supply underway, their number corresponding to the quantity supplied and their frequency corresponding to the instantaneous flow-rate; the piloting of the volumetric suction pump, on the other hand, which is effected by modulating its instantaneous rate, or the number of revs per minute, on the basis of the instantaneous frequency of the meter impulses, is not as accurate in the final result for obtaining a constant ratio between the volumetric flow-rate of the liquid supplied and the vapour sucked up.
  • volumetric pumps for vapour recovery in fuel pumps are, in fact, blade pumps, roll pumps and alternative pumps to these, have a characteristic flow-rate/velocity curve which is not at all linear and which therefore does not allow a constant ratio to be obtained between the flow-rates of the liquid supplied and the vapour sucked up, if operating on the basis of the frequency of the meter/generator impulses, with a variation in the supply rate and consequently linearly regulating the revs/min of the volumetric pump.
  • the system for controlling the recovery of vapours envisages the positioning of a flow-rate sensor 4 on the vapour return line, preferably upstream of said vapour suction pump 26, whose signal is acquired from said electronic unit 22.
  • said electronic control unit comprises an analogical acquisition unit 221, a running unit 222 of the recovery pump and a visualization unit 223.
  • the acquisition unit is suitable for processing and filtering the signal coming from the flow-rate sensor 4, and sending it to the running unit, which effects a processing and controls the electric motor 26 which activates the vapour suction pump 27.
  • the quantity of fuel supplied is detected by means of the meter 14 connected to said impulse generator 20, which generates an electric impulse for each unit of fuel supplied, for example for every centiliter; said impulse signal has a frequency proportional to the flow-rate and is transmitted both to the indicator 21 and to said running unit 222.
  • the processing effected by said running unit 222 effects a comparison between the quantity of fuel supplied and the quantity of vapour recovered, from this comparison, a signal is emitted for said electric motor 26 so as to regulate the suction of the recovery pump 27, maintaining the ratio between the quantity of fuel supplied and the quantity of vapour recovered at a pre-established value, preferably constant over a period of time.
  • Figure 3a-3c shows detailed graphs which indicate a first curve 51 which refers to the quantity of fuel supplied with time from a column as illustrated in figure 1, and a second curve 52 which refers to the quantity of vapour recovered with time by means of the control system according to the present invention.
  • Said running unit 222 has a communication port, for example, a serial port, with a computer whereby it is possible to establish the functioning of the unit itself.
  • said pre-established ratio can be set between the quantity of fuel supplied and the quantity of vapour to be recovered, it is possible to establish the rotation direction of the recovery pump, set the functioning of the recovery pump at the maximum regime, set the rotation of the recovery pump at fixed revs, set the sampling time whereby the data is detected by the flow- rate sensor. Furthermore, with the advantageous help of said computer, it is possible to reactivate the system once this has inhibited the functioning of the column due to the same anomaly repeated for a pre-established number of times, for example ten consecutive supplies in which each ratio is outside a pre-determined value.
  • the control system visualizes the data processed by the processing unit and detected by the flow-rate sensor by means of said visualization unit 223, which is connected to the electronic indicator of the column.
  • functioning anomalies of the column can be visualized, for example a quantity of vapour recovered outside said pre-determined ratio.
  • Other data relating to functioning anomalies can also be visualized, such as, for example, the hour and date of the occurrence of the anomaly, the number of supplies effected, the number of supplies effected in which an anomaly has been detected, the number of supplies consecutively effected in which an anomaly has been detected.
  • the whole control unit can be advantageously connected by means of a suitable port, for example a serial port, to a central unit of the filling station as a whole.
  • a suitable port for example a serial port
  • each column of the station can be connected to said central unit of the station from which it is possible to detect the various anomalies which can occur in each column.
  • FIG. 4 illustrates an example of a flow-rate sensor according to the present invention.
  • Said sensor is of the electromagnetic type and comprises a pair of opposite magnets having the same polarity which move in relation to one another along a longitudinal axis of the sensor as a result of the variations in the vapour flow, a magnetic detector suitable for measuring the variations in the magnetic field produced by the movement of the two magnets and due to said flow variations.
  • the senor comprises a hollow body 41, preferably cylindrical, having at its opposite ends a pair of fittings 42 and 43 for connecting said sensor to a fluid transporting duct, for example for the vapour suction duct 25 of figure 1.
  • a piston 44 Inside said hollow cylindrical body 41, there are preferably a piston 44 and a support 45 inside which the piston slides along the longitudinal axis of said hollow body.
  • a housing 441 for a first magnet 442 At one of the ends of said piston, there is a housing 441 for a first magnet 442, and at the end facing said piston, said support 45 has an analogous housing 451 for a second magnet 452.
  • Said magnets are polarized with the same sign and consequently develop an electromagnetic repulsion force if placed near each other.
  • the flow-rate sensor preferably comprises a regulation screw 46 of the position of said second magnet inside the housing 451 on the support 45, a blocking nut 47 and a pair of filters 421 and 431.
  • the sensor also comprises a magnetic detector 48 situated on the lateral surface of the hollow body, preferably in an intermediate position corresponding to the internal area of the body in which the two magnets are situated.
  • the sensor is installed in series with a duct in which a fluid flows, in order to measure the flow-rate of the fluid which passes through the duct and consequently establish the quantity of fluid supplied.
  • the functioning of the flow-rate sensor is as follows .
  • the senor is capable of measuring the flow-rate of a fluid which passes through it following the direction of the arrow F.
  • the fluid crosses the sensor entering the hollow body by means of the connection 42 and pushes the piston 44, along the longitudinal axis X of the hollow body 41 towards the support 45.
  • This thrust tends to draw the magnets closer to each other and is contrasted by the electromagnetic repulsion force created thereby.
  • the magnetic field present inside the hollow body changes in correspondence with the change in distance between the two magnets.
  • the magnetic field detector 48 is capable of measuring these variations in the magnetic field and generates an electric signal corresponding to said variations.
  • the variations in flow-rate of the fluid thus cause a variation in the distance between the two magnets and consequently a variation in the magnetic field.
  • the variation in the magnetic field is detected and an electric signal is generated, corresponding to the variation in the flow-rate of the fluid which crosses the flow-rate sensor according to the present invention.
  • the regulation screw is used to regulate the maximum distance between the two magnets when the sensor is not crossed by the fluid and therefore to establish a signal starting from a pre-established pressure exerted by the fluid on the piston.
  • the magnetic detector can be a sensor with a digital outlet, with which it is only possible to generate an electric signal when a pre-established pressure has been reached on the piston, and therefore basically a flow- rate sensor which detects the attainment of a certain flow-rate.
  • a magnetic detector with a linear outlet By using a magnetic detector with a linear outlet, it is possible to obtain an electric signal which is substantially proportional to the flow-rate to be measured.
  • the flow-rate sensor according to the present invention allows a very low friction to be obtained at the minimum flow-rates, increasing with an increase in the flow-rate itself, as the magnetic repulsion force between the two magnets increases in a non-linear manner as the distance between them is reduced (the repulsion force increases exponentially) .
  • the sensitivity of this sensor is consequently extremely high for small variations in flow-rate.
  • the regulation screw is also suitable for modifying said sensitivity by increasing or reducing the distance between the magnets.
  • the sensor according to the present invention allows a linearity and constancy of the measurement to be obtained in aggressive plants and environments as there is no electric part in direct contact with the gas or liquid whose flow-rate is to be measured.

Abstract

System for controlling the recovery of vapours in a fuel pump column, comprising a fuel supply line, a fuel supply pump from a cistern of said fuel pump to a tank of a ve­hicle, and a recovery line of the vapours discharged from the tank of said vehicle during the fuel supply compris­ing a suction pump of the vapours from said tank. The system comprises an electronic control unit which re­ceives, from said suction line, a signal relating to the quantity of fuel supplied and which controls said vapour suction pump.

Description

SYSTEM FOR CONTROLLING THE RECOVERY OF VAPOURS IN A FUEL PUMP COLUMN
The present invention relates to a system for controlling the recovery of vapours in fuel pump columns. In particular the present invention relates to a system for controlling the recovery of vapours in fuel pump columns equipped with a device for recovering the vapours discharged during refueling operations of vehicles.
In fuel pumps, and in particular in road filling pumps for the refueling of vehicles, the safety and environmental protection regulations require that the vapour phase, consisting of a mixture of air and fuel vapours, discharged from vehicle tanks during refueling, are not dispersed in the atmosphere.
This emission is essentially due to the effect of the movement on the part of the liquid that is entering the tank, which reduces the volume above its level and expels an equal volume of vapour phase.
The known art envisages the suction of this air/vapour phase by equipping the fuel supply guns with both fuel supply nozzles and suction nozzles, connected to volumetric pumps.
The supply gun is connected to the column with a conveyance pipe of the liquid fuel fed to a pumping group at a varying flow-rate and with a suction pipe connected to a volumetric vapour suction pump which is activated with a flow-rate strictly correlated, at each instant, with the fuel conveyance flow-rate.
Various systems have been proposed in the known art, for the recovery of vapours, or more precisely the air/vapour phase, discharged from vehicle tanks during refueling. Italian patent IT 1312725 filed by the same Applicant describes a device and process for controlling the recovery of vapours in fuel pump columns of the single- or multi-product type, which comprises a vapour suction pump, connected to an electric motor, whose rotation rate is modulated on the basis of controls deriving from an electronic control unit and signals coming from an impulse generator which indicate the quantity of fuel supplied by the pump, by means of an electronic indicator.
The quantity of vapours to be recovered is calculated on the basis of the quantity of fuel supplied by means of characteristic pre-memorized curves in said control unit which connect the volume of vapour recovered from the device with the volume of fuel supplied, a function which, in reality, follows a non-linear trend. The control device regulates the volumetric pump of the vapour recovery on the basis of said curve.
The Applicant has observed that by surveying in real time the flow-rate of the vapour recovery line in a fuel pump column, it is possible to almost exactly evaluate the ratio between the fuel supplied and the quantity of vapour to be recovered without having to effect estimates and calculations which can, in some cases, prove to be inaccurate.
The Applicant has found that by inserting a flow- rate sensor onto the vapour return line and monitoring in real time the quantity of vapour recovered, it is possible to constantly control the flow-rate of the vapour recovery pump.
The Applicant has set up a system for the recovery of vapours in a fuel pump column by means of a magnetic flow-rate sensor.
An aspect of the present invention relates to a system for controlling the recovery of vapours in a fuel pump column, said column comprising
• at least one fuel supply line, fuel supply pump from a cistern of said fuel pump to the tank of a vehicle,
• at least one recovery line of the vapours discharged from the tank of said vehicle during fuel supply comprising a suction pump of the vapours from said tank,
• at least one electronic control unit which receives a signal from said suction line, relating to the quantity of fuel supplied and which controls said vapour suction pump, characterized in that
• said system comprises a flow-rate sensor situated on the vapour return line which generates a signal relating to the flow-rate of the vapour recovered and
• said control unit detects said signal relating to the flow-rate of vapour recovered and controls the suction pump so as to maintain the ratio between the quantity of fuel supplied and the quantity of vapour recovered at a pre-established value.
The characteristics and advantages of the system according to the present invention will appear more evident from the following illustrative but non-limiting description of one of its typical embodiments, referring to the schematic drawings enclosed, in which:
Figure 1 is a schematic representation of a pump column to a supply gun with vapour phase recovery;
Figure 2 represents a block scheme of an embodiment of the control system for the recovery of vapours, according to the present invention; Figures 3a-3c show graphs which illustrate the quantity of fuel supplied from a pump column and the quantity of vapour recovered by means of the control system according to the present invention;
Figure 4 schematically illustrates a flow-rate sensor, according to the present invention.
Figure 1 illustrates a fuel pump column 10 equipped with a box-shaped supporting structure 11 which contains and supports its organs .
The fuel is contained in an underground cistern, not shown in the figure, from which the fuel is sent by means of a supply line, which comprises an inlet 12, a pumping group 13 which is connected with a supply gun 18, a meter 14 which measures the quantity of fuel supplied, before sending it, through a duct 15, to a separator 16, from which there is a flexible tube 17 of the supply gun 18.
An impulse generator 20 is connected to the meter 14, which generates an electric impulse for each unit of fuel supplied, for example for each centiliter; this impulse signal has a frequency which is proportional to the flow-rate and is transmitted to an indicator 21, which, on the basis of the number of impulses, calculates and indicates the quantity supplied and the relative refueling price.
The same signal relating to the quantity of fuel supplied is transmitted to an electronic control unit 22.
The column also comprises a recovery line of the vapours discharged from the tank of a vehicle during fuel supply. In the tube 17 of the supply gun 18, there is a fuel conveyance duct 23, which is the extension of the conveyance duct 15 to the supply nozzle, and also a return duct 24 connected to a suction nozzle situated close to the supply nozzle.
The vapour recovery line comprises said nozzle which sucks the vapours discharged from the tank which is being filled, the return duct 24 which is joined in the separator 16 to a duct 25, a volumetric vapour suction pump 26 connected to said duct 25, which is activated by a motor 27 driven by the electronic control unit 22.
The number of revs of said motor is preferably uninterruptedly connected to the frequency of the impulse signal of the generator 20, so as to correlate the revs of the pump 26, and consequently the volumetric suction pump, to the fuel conveyance flow-rate.
The emission of the volumetric pump 26 preferably re-enters the underground cistern of the pump, by means of the duct 28, from which the fuel is removed; the volumetric ratio between the fuel supplied and gaseous phase sucked up, is generally established and maintained within a range of values around the unitary value; said fixed value can vary in relation to the type of fuel and environmental conditions.
The fuel supply is typically effected with a varying flow-rate and is regulated by the attendant by the pressure exerted on a regulation lever 30 of the gun, whereas the suction flow-rate must constantly follow the course of the conveyance flow-rate.
In practice, the sequence of impulses faithfully represents the situation, at each instant, of the liquid supply underway, their number corresponding to the quantity supplied and their frequency corresponding to the instantaneous flow-rate; the piloting of the volumetric suction pump, on the other hand, which is effected by modulating its instantaneous rate, or the number of revs per minute, on the basis of the instantaneous frequency of the meter impulses, is not as accurate in the final result for obtaining a constant ratio between the volumetric flow-rate of the liquid supplied and the vapour sucked up.
The most widely used types of volumetric pumps for vapour recovery in fuel pumps are, in fact, blade pumps, roll pumps and alternative pumps to these, have a characteristic flow-rate/velocity curve which is not at all linear and which therefore does not allow a constant ratio to be obtained between the flow-rates of the liquid supplied and the vapour sucked up, if operating on the basis of the frequency of the meter/generator impulses, with a variation in the supply rate and consequently linearly regulating the revs/min of the volumetric pump.
The system for controlling the recovery of vapours according to the present invention, with particular reference to the example of figure 2, envisages the positioning of a flow-rate sensor 4 on the vapour return line, preferably upstream of said vapour suction pump 26, whose signal is acquired from said electronic unit 22.
In particular, said electronic control unit comprises an analogical acquisition unit 221, a running unit 222 of the recovery pump and a visualization unit 223.
The acquisition unit is suitable for processing and filtering the signal coming from the flow-rate sensor 4, and sending it to the running unit, which effects a processing and controls the electric motor 26 which activates the vapour suction pump 27.
The quantity of fuel supplied is detected by means of the meter 14 connected to said impulse generator 20, which generates an electric impulse for each unit of fuel supplied, for example for every centiliter; said impulse signal has a frequency proportional to the flow-rate and is transmitted both to the indicator 21 and to said running unit 222. The processing effected by said running unit 222 effects a comparison between the quantity of fuel supplied and the quantity of vapour recovered, from this comparison, a signal is emitted for said electric motor 26 so as to regulate the suction of the recovery pump 27, maintaining the ratio between the quantity of fuel supplied and the quantity of vapour recovered at a pre-established value, preferably constant over a period of time.
Figure 3a-3c shows detailed graphs which indicate a first curve 51 which refers to the quantity of fuel supplied with time from a column as illustrated in figure 1, and a second curve 52 which refers to the quantity of vapour recovered with time by means of the control system according to the present invention.
From the curves, it can be observed that initially, as soon as fuel is supplied by means of the supply gun, the quantity of vapour recovered is lower than the quantity of fuel supplied. After a transitory functioning period of the control system, it can be noted that the second curve 52 tends to become parallel to the first curve. In other words, the control system, after said transitory period, tends to regulate the recovery pump so as to maintain a constant ratio between the quantity of fuel supplied and the quantity of vapour recovered until the supply has been completed. Said running unit 222 has a communication port, for example, a serial port, with a computer whereby it is possible to establish the functioning of the unit itself. For example, said pre-established ratio can be set between the quantity of fuel supplied and the quantity of vapour to be recovered, it is possible to establish the rotation direction of the recovery pump, set the functioning of the recovery pump at the maximum regime, set the rotation of the recovery pump at fixed revs, set the sampling time whereby the data is detected by the flow- rate sensor. Furthermore, with the advantageous help of said computer, it is possible to reactivate the system once this has inhibited the functioning of the column due to the same anomaly repeated for a pre-established number of times, for example ten consecutive supplies in which each ratio is outside a pre-determined value.
According to the present invention, the control system visualizes the data processed by the processing unit and detected by the flow-rate sensor by means of said visualization unit 223, which is connected to the electronic indicator of the column. In this way, according to a characteristic of the present invention, functioning anomalies of the column can be visualized, for example a quantity of vapour recovered outside said pre-determined ratio. Other data relating to functioning anomalies can also be visualized, such as, for example, the hour and date of the occurrence of the anomaly, the number of supplies effected, the number of supplies effected in which an anomaly has been detected, the number of supplies consecutively effected in which an anomaly has been detected.
The whole control unit can be advantageously connected by means of a suitable port, for example a serial port, to a central unit of the filling station as a whole. In this way, each column of the station can be connected to said central unit of the station from which it is possible to detect the various anomalies which can occur in each column.
Figure 4 illustrates an example of a flow-rate sensor according to the present invention. Said sensor is of the electromagnetic type and comprises a pair of opposite magnets having the same polarity which move in relation to one another along a longitudinal axis of the sensor as a result of the variations in the vapour flow, a magnetic detector suitable for measuring the variations in the magnetic field produced by the movement of the two magnets and due to said flow variations.
In particular, the sensor comprises a hollow body 41, preferably cylindrical, having at its opposite ends a pair of fittings 42 and 43 for connecting said sensor to a fluid transporting duct, for example for the vapour suction duct 25 of figure 1.
Inside said hollow cylindrical body 41, there are preferably a piston 44 and a support 45 inside which the piston slides along the longitudinal axis of said hollow body. At one of the ends of said piston, there is a housing 441 for a first magnet 442, and at the end facing said piston, said support 45 has an analogous housing 451 for a second magnet 452.
Said magnets are polarized with the same sign and consequently develop an electromagnetic repulsion force if placed near each other.
Furthermore, the flow-rate sensor preferably comprises a regulation screw 46 of the position of said second magnet inside the housing 451 on the support 45, a blocking nut 47 and a pair of filters 421 and 431.
The sensor also comprises a magnetic detector 48 situated on the lateral surface of the hollow body, preferably in an intermediate position corresponding to the internal area of the body in which the two magnets are situated.
The sensor is installed in series with a duct in which a fluid flows, in order to measure the flow-rate of the fluid which passes through the duct and consequently establish the quantity of fluid supplied. The functioning of the flow-rate sensor is as follows .
According to the example of figure 4, the sensor is capable of measuring the flow-rate of a fluid which passes through it following the direction of the arrow F.
The fluid crosses the sensor entering the hollow body by means of the connection 42 and pushes the piston 44, along the longitudinal axis X of the hollow body 41 towards the support 45.
This thrust tends to draw the magnets closer to each other and is contrasted by the electromagnetic repulsion force created thereby.
The magnetic field present inside the hollow body changes in correspondence with the change in distance between the two magnets. The magnetic field detector 48 is capable of measuring these variations in the magnetic field and generates an electric signal corresponding to said variations. The variations in flow-rate of the fluid thus cause a variation in the distance between the two magnets and consequently a variation in the magnetic field. In short, the variation in the magnetic field is detected and an electric signal is generated, corresponding to the variation in the flow-rate of the fluid which crosses the flow-rate sensor according to the present invention. The regulation screw is used to regulate the maximum distance between the two magnets when the sensor is not crossed by the fluid and therefore to establish a signal starting from a pre-established pressure exerted by the fluid on the piston.
The magnetic detector can be a sensor with a digital outlet, with which it is only possible to generate an electric signal when a pre-established pressure has been reached on the piston, and therefore basically a flow- rate sensor which detects the attainment of a certain flow-rate. By using a magnetic detector with a linear outlet, it is possible to obtain an electric signal which is substantially proportional to the flow-rate to be measured.
The flow-rate sensor according to the present invention allows a very low friction to be obtained at the minimum flow-rates, increasing with an increase in the flow-rate itself, as the magnetic repulsion force between the two magnets increases in a non-linear manner as the distance between them is reduced (the repulsion force increases exponentially) .
The sensitivity of this sensor is consequently extremely high for small variations in flow-rate. The regulation screw is also suitable for modifying said sensitivity by increasing or reducing the distance between the magnets. Furthermore the sensor according to the present invention allows a linearity and constancy of the measurement to be obtained in aggressive plants and environments as there is no electric part in direct contact with the gas or liquid whose flow-rate is to be measured.

Claims

1. A system for controlling the recovery of vapours in a fuel pump column, said column comprising
• at least one fuel supply line, fuel supply pump from a cistern of said fuel pump to the tank of a vehicle,
• at least one recovery line of the vapours discharged from the tank of said vehicle during fuel supply comprising a suction pump of the vapours from said tank,
• at least one electronic control unit which receives a signal from said suction line, relating to the quantity of fuel supplied and which controls said vapour suction pump, characterized in that
• said system comprises a flow-rate sensor situated on the vapour return line which generates a signal relating to the flow-rate of the vapour recovered and
• said control unit detects said signal relating to the flow-rate of vapour recovered and controls the suction pump so as to maintain the ratio between the quantity of fuel supplied and the quantity of vapour recovered at a pre-established value.
2. The system according to claim 1, wherein said flow- rate sensor is an electromagnetic sensor.
3. The system according to claim 1, wherein said flow -rate sensor comprises a pair of opposite magnets having the same polarity which move in relation to one another along a longitudinal axis of the sensor as a result of the variations in the vapour flow, a magnetic detector suitable for measuring the variations in the magnetic field produced by the movement of the two magnets and due to said flow variations.
4. The system according to claim 3, wherein said sensor comprises a hollow body, equipped at its opposite ends with a pair of fittings for connecting said sensor to a fluid transporting duct.
5. The system according to claim 4, wherein said sensor comprises a piston and a support inside which the piston slides along the longitudinal axis of said sensor.
6. The system according to claim 5, wherein at one of the ends of said piston, there is a housing for one of said magnets, and at the end facing said piston, said support has an analogous housing for the other magnet.
7. The system according to claim 6, wherein said sensor comprises a regulation screw of the position of said second magnet, inside the housing present on said support.
8. The system according to claim 1, wherein said electronic control unit comprises an analogical acquisition unit suitable for processing and filtering the signal coming from the flow-rate sensor, a running unit of the recovery pump which effects a processing and controls the electric motor which activates the vapour suction pump.
9. The system according to claim 8, wherein said electronic control unit comprises a visualization unit connected to an electronic indicator of the column in order to visualize functioning anomalies of the column itself.
10. The system according to claim 8, wherein said electronic control unit can be connected by means of a communication port, to a central unit of the filling station.
11. The system according to claim 8, wherein said running unit has a communication port with a computer whereby it is possible to set the functioning of the unit itself.
PCT/EP2004/002567 2003-03-14 2004-03-11 System for controlling the vapour recovery of a fuel pump WO2004080884A2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITMI20030494 ITMI20030494A1 (en) 2003-03-14 2003-03-14 SYSTEM FOR THE CONTROL OF THE VAPOR RECOVERY IN ONE
ITMI2003A000494 2003-03-14

Publications (3)

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WO2004080884A2 true WO2004080884A2 (en) 2004-09-23
WO2004080884A8 WO2004080884A8 (en) 2004-11-25
WO2004080884A3 WO2004080884A3 (en) 2005-01-06

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TW (1) TW200505785A (en)
WO (1) WO2004080884A2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008009119A2 (en) 2006-07-18 2008-01-24 Fuel Transfer Technologies Portable pumping apparatus for concurrently pumping liquid from a source container to a destination container and pumping vapor from the destination container to the source container
US8925595B2 (en) 2009-01-28 2015-01-06 Fuel Transfer Technologies Inc. Nozzle for use in a non-overflow liquid delivery system

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1043594A (en) * 1962-03-21 1966-09-21 Vincent Jerome Cushing Magnetic flowmeter apparatus
DE3829063A1 (en) * 1988-08-26 1990-03-08 Danfoss As METHOD FOR MAGNETIC-INDUCTIVE FLOW MEASUREMENT AND MAGNETIC-INDUCTIVE FLOW METER
USRE35238E (en) * 1990-05-21 1996-05-14 Gilbarco, Inc. Vapor recovery system for fuel dispenser
US6047745A (en) * 1995-08-10 2000-04-11 Tokheim Services France Process for the recovery of steam emitted in a liquid distribution plant
US20010001179A1 (en) * 1999-03-19 2001-05-17 Healy Systems, Inc., A New Hampshire Corporation Coaxial vapor flow indicator with pump speed
US20010020493A1 (en) * 1999-11-17 2001-09-13 Nanaji Seifollah S. Vapor flow and hydrocarbon concentration sensor for improved vapor recovery in fuel dispensers

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1043594A (en) * 1962-03-21 1966-09-21 Vincent Jerome Cushing Magnetic flowmeter apparatus
DE3829063A1 (en) * 1988-08-26 1990-03-08 Danfoss As METHOD FOR MAGNETIC-INDUCTIVE FLOW MEASUREMENT AND MAGNETIC-INDUCTIVE FLOW METER
USRE35238E (en) * 1990-05-21 1996-05-14 Gilbarco, Inc. Vapor recovery system for fuel dispenser
US6047745A (en) * 1995-08-10 2000-04-11 Tokheim Services France Process for the recovery of steam emitted in a liquid distribution plant
US20010001179A1 (en) * 1999-03-19 2001-05-17 Healy Systems, Inc., A New Hampshire Corporation Coaxial vapor flow indicator with pump speed
US20010020493A1 (en) * 1999-11-17 2001-09-13 Nanaji Seifollah S. Vapor flow and hydrocarbon concentration sensor for improved vapor recovery in fuel dispensers

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008009119A2 (en) 2006-07-18 2008-01-24 Fuel Transfer Technologies Portable pumping apparatus for concurrently pumping liquid from a source container to a destination container and pumping vapor from the destination container to the source container
EP2049434A2 (en) * 2006-07-18 2009-04-22 Fuel Transfer Technologies Inc. Portable pumping apparatus for concurrently pumping liquid from a source container to a destination container and pumping vapor from the destination container to the source container
EP2049433A2 (en) * 2006-07-18 2009-04-22 Fuel Transfer Technologies Inc. Portable fluid exchange system for concurrently pumping liquid from a source container to a destination container and pumping vapor from the destination container to the source container
EP2049434A4 (en) * 2006-07-18 2012-02-22 Fuel Transfer Technologies Inc Portable pumping apparatus for concurrently pumping liquid from a source container to a destination container and pumping vapor from the destination container to the source container
EP2049433A4 (en) * 2006-07-18 2012-02-22 Fuel Transfer Technologies Inc Portable fluid exchange system for concurrently pumping liquid from a source container to a destination container and pumping vapor from the destination container to the source container
US8578974B2 (en) 2006-07-18 2013-11-12 Fuel Transfer Technologies Inc. Portable fluid exchange system for concurrently pumping liquid from a source container to a destination container and pumping vapor from the destination container to the source container
US8925595B2 (en) 2009-01-28 2015-01-06 Fuel Transfer Technologies Inc. Nozzle for use in a non-overflow liquid delivery system
US8936051B2 (en) 2009-01-28 2015-01-20 Fuel Transfer Technologies Inc. Non-overflow liquid delivery system

Also Published As

Publication number Publication date
TW200505785A (en) 2005-02-16
WO2004080884A8 (en) 2004-11-25
ITMI20030494A1 (en) 2004-09-15
WO2004080884A3 (en) 2005-01-06

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