EP0440845B1 - Système de distribution pour carburants liquides - Google Patents

Système de distribution pour carburants liquides Download PDF

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Publication number
EP0440845B1
EP0440845B1 EP90102372A EP90102372A EP0440845B1 EP 0440845 B1 EP0440845 B1 EP 0440845B1 EP 90102372 A EP90102372 A EP 90102372A EP 90102372 A EP90102372 A EP 90102372A EP 0440845 B1 EP0440845 B1 EP 0440845B1
Authority
EP
European Patent Office
Prior art keywords
pump
dispensing
fuel
delivery
valves
Prior art date
Legal status (The legal status 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 status listed.)
Expired - Lifetime
Application number
EP90102372A
Other languages
German (de)
English (en)
Other versions
EP0440845A1 (fr
Inventor
Gert Miller
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Scheidt and Bachmann GmbH
Original Assignee
Scheidt and Bachmann GmbH
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 Scheidt and Bachmann GmbH filed Critical Scheidt and Bachmann GmbH
Priority to EP90102372A priority Critical patent/EP0440845B1/fr
Priority to ES199090102372T priority patent/ES2042092T3/es
Priority to AT90102372T priority patent/ATE89533T1/de
Priority to DE9090102372T priority patent/DE59001502D1/de
Publication of EP0440845A1 publication Critical patent/EP0440845A1/fr
Application granted granted Critical
Publication of EP0440845B1 publication Critical patent/EP0440845B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • 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
    • B67D7/06—Details or accessories
    • B67D7/36—Arrangements of flow- or pressure-control valves
    • 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
    • B67D7/06—Details or accessories
    • B67D7/58—Arrangements of pumps
    • B67D7/62—Arrangements of pumps power operated
    • B67D7/66—Arrangements of pumps power operated of rotary type

Definitions

  • the invention relates to a dispensing device for dispensing liquid fuels with at least two dispensing valves, each of which is supplied with fuel by its own measuring device, preferably a piston counter, by a common pump with a downstream gas separator, the pump being driven by an electric motor which, when a Fuel valve is switched on from its holder, fuel being conveyed via a bypass in a closed circuit until the fuel nozzle opens.
  • Such dispensing devices are known.
  • two dispensing valves each arranged at one end of a dispensing hose, are usually supplied by one pump.
  • a gas separator is arranged downstream of this pump in order to ensure that the measuring device assigned to each nozzle valve is supplied with the fuel in a bubble-free manner and thus to ensure that the dispensed fuel is properly measured.
  • the total delivery volume of the pump in the known dispensing devices is approximately twice the respective maximum dispensing quantity of a dispensing valve.
  • the maximum dispensing quantity per nozzle for example at 40 to 45 liters per minute; the total flow of the pump in this case is about 80 liters per minute if this pump is used to supply two taps.
  • more than two nozzle valves can be supplied by a common pump with a correspondingly higher total delivery rate.
  • the electric motor driving the pump is already switched on when one of the dispensing valves is removed from its holder, it is ensured that sufficient delivery pressure is always available when one or both dispensing valves are inserted after being inserted into the dispenser Tank to be opened.
  • the fuel conveyed by the pump between the removal of the first dispensing valve belonging to the dispensing device from its holder up to the opening of this dispensing valve is conveyed via a bypass in a closed circuit, with full pump output.
  • the check valve either opens and closes at shorter intervals or this check valve remains in an intermediate position. In all these cases, however, throttling losses occur at the check valve in the bypass line due to the negative pressure that occurs. This negative pressure not only leads to vortex formation, but also to gas formation in particular because the liquid fuel tends to gasify very quickly.
  • This fuel gas generated in the bypass is separated in the gas separator downstream of the pump, but has the major disadvantage that not only relatively large amounts of gas are produced, but that during this gas formation the additives added to the liquid fuel are eliminated, which increases the knock resistance of the fuel serve. These additives are volatile substances which are only present in very small quantities in the fuel and which, when they are excreted, lead to a rapid deterioration in fuel quality.
  • the invention is based on the object of developing a dispensing device of the type described at the outset with at least two dispensing valves supplied by a common pump, that the throttle losses described above, leading to gas formation and thus to quality reduction, are largely avoided.
  • the solution to this problem by the invention is characterized in that the delivery capacity of the pump is regulated by a controller depending on the measurement result of a flow meter installed in the bypass line.
  • This regulator is set in such a way that a certain target quantity, for example 0.5 liters per minute, always flows through the bypass to generate and maintain the required delivery pressure, but that no large amounts of fuel are circulated through the bypass. As a result, the gas formation resulting from the bypass operation is reduced to a minimum, so that losses in quality are avoided both before and during each dispensing operation.
  • a certain target quantity for example 0.5 liters per minute
  • the invention proposes, as an alternative to the arrangement of the flow meter built into the bypass line, which serves to regulate the delivery rate of the pump, the delivery rate of the pump by a controller depending on the number of outlets to control dispensing valves removed from their holder according to their share in the total delivery volume through all dispensing valves, taking into account the delivery losses.
  • a simple controller can be used in this case, which reduces the delivery capacity of the pump to 60 percent, for example, if only one of a total of two dispensing valves is removed from the holder.
  • This alternative design is particularly suitable for retrofitting existing dispensing devices.
  • the delivery rate of the pump can be changed via the speed of the electric motor driving the pump, with the aid of known measures, for example a phase control or a frequency change in three-phase motors.
  • the invention can also be used when pumps are used which are driven at a constant speed, but whose delivery rate can be changed by adjusting the pump, for example the eccentricity of a vane pump.
  • the dispensing device comprises two dispensing masts 1, in each of which a dispensing hose 2 is arranged so that it can be pulled out.
  • Each dispensing hose 2 is provided with a dispensing valve 3 and guided over two deflection rollers 4.
  • Each nozzle 2 is connected to a measuring mechanism 6 via a pipeline 5.
  • These measuring units 6 are designed as piston counters in the exemplary embodiment.
  • a holder 7 is provided on each nozzle 1, into which the respective nozzle 3 is inserted when not in use.
  • the two fuel hoses 2 are supplied with liquid fuel from a fuel reservoir (not shown in the drawing) via a filter 8 by a pump 9 common to both fuel hoses 2.
  • this pump 9 is driven by an electric motor 10 via a drive belt 10a.
  • the pump 9 sucks in the liquid fuel through the filter 8 and conveys it via a gas separator 11 and a check valve 12 to the two measuring units 6.
  • two solenoid valves 14 are arranged through which the measuring unit 6, which is out of operation, is separated from the pressure line 13.
  • the electric motor 10 is switched on as soon as one of the two dispensing valves 3 is removed from its holder 7.
  • the by Opening this nozzle 3 fuel delivered by the pump 9 is fed via a bypass line 15 in a closed circuit.
  • This bypass line 15 runs between the gas separator 11 and the suction line 16 to the pump 9.
  • the bypass line 15 is connected to this suction line 16 with the interposition of a check valve 17.
  • a return suction line 18 runs parallel to the bypass line 15 between the gas separator 11 and the suction line 16. Via this return suction line 18, which is opened or closed by a float switch 19 arranged in the area of the gas separator 11, the fuel that accumulates in the gas separator 11 is returned to pump 9.
  • the construction of the dispensing device described above is identical for both exemplary embodiments according to FIGS. 1 and 2. Since, in certain operating states, a more or less large amount of fuel is conveyed in the closed circuit via the bypass line 15, pressure losses occur in the check valve 17 of this bypass line 15, which on the one hand lead to undesired eddy formation and on the other hand to the formation of gas bubbles. These gas bubbles are sucked in by the pump 9 and separated in the gas separator 11; however, the mostly volatile additives that have been added to the liquid fuel to increase its knock resistance are eliminated. In particular with a high proportion of gas bubbles, such as results from the circulation of a larger amount of fuel in the closed bypass circuit, this addition of the additives leads to a noticeable reduction in the quality of the liquid fuel.
  • a flow meter 20 is arranged in the bypass line 15 in the first exemplary embodiment according to FIG.
  • the delivery rate of the pump 9 is regulated by a controller 21.
  • the delivery rate of the pump 9 is regulated by changing the speed of the electric motor 10 driving the pump 9, for example in a manner known per se via a phase control or a frequency change, provided that the electric motor 10 is a three-phase motor.
  • the controller 21 is set, for example, so that a set amount, for example 0.5 liters per minute, always flows through the bypass line 15 in order to generate and maintain the required delivery pressure in the dispensing hoses 2. As soon as this target quantity is exceeded, the pump speed is reduced. In this way it is ensured that the amount of fuel circulated in a closed circuit after the first nozzle 3 has been removed from the holder 7 before this nozzle 3 is opened does not exceed the stated target quantity. As soon as a larger amount of fuel is required by opening the nozzle 3, the delivery capacity of the pump 9 is increased by increasing the speed.
  • bypass line 15 Since the amount of fuel circulated via the bypass line 15 is kept at the setpoint of, for example, 0.5 liters per minute even during the entire dispensing process, the vacuum in the bypass line 15 and thus the formation of gas bubbles are minimized in all operating states. A reduction in fuel quality is therefore impossible.
  • a flow meter 20 arranged in the bypass line 15 and a complex controller 21 are dispensed with.
  • the delivery rate of the pump 9 or the speed of the electric motor 10 is controlled by a controller 22 as a function of the number of dispensing valves 3 removed from its holder 7, in accordance with their share in the total delivery rate through all dispensing valves 3, taking into account the delivery losses.
  • the dispensing device is equipped with two dispensing valves 3 supplied by a common pump 9, which require a maximum delivery capacity of the pump 9 of 80 liters per minute when the system is started up, for example, the delivery rate of the pump is reduced 9 by reducing the speed to 40 to 45 liters per minute, provided only one nozzle 3 has been removed from its holder 7.
  • the controller 22 can consequently be made considerably simpler than the controller 21 reacting to the measurement results of the flow meter 20 in the embodiment according to FIG. 1.
  • the embodiment according to FIG. 2 is therefore particularly suitable for retrofitting existing dispensing devices, since an intervention in the hydraulic part the dispensing devices is omitted and the switches 23 required for signaling the controller 22 are already present on the holders 7 for the dispensing valves 3.
  • the above-described regulation or control of the delivery capacity of the pump 9 also has the advantage that in all operating states only that energy is used to drive the pump 9 that is required to maintain the required delivery pressure in the hydraulic system. This results in a certain amount of energy savings.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Loading And Unloading Of Fuel Tanks Or Ships (AREA)
  • Feeding And Controlling Fuel (AREA)

Claims (3)

  1. Système de distribution pour carburants liquides, comprenant au moins deux vannes de distribution (3) qui sont alimentées en carburant, chacune par l'intermédiaire de son propre dispositif de mesure (6), de préférence d'un compteur à piston, par une pompe commune (9) en aval de laquelle est implanté un séparateur de gaz (11), la pompe (9) étant commandée par un moteur électrique (10) qui est mis en marche lorsqu'une vanne de distribution (3) est décrochée de son support (7), le carburant circulant en circuit fermé par l'intermédiaire d'une dérivation (15) jusqu'à l'ouverture de la vanne de distribution (3), caractérisé en ce que la capacité de refoulement de la pompe (9) est régulée par un régulateur (21) en fonction du résultat de mesure d'un débitmètre (20) implanté sur la conduite de dérivation (15).
  2. Système de distribution pour carburants liquides, comprenant au moins deux vannes de distribution (3) qui sont alimentées en carburant, chacune par l'intermédiaire de son propre dispositif de mesure (6), de préférence d'un compteur à piston, par une pompe commune (9) en aval de laquelle est implanté un séparateur de gaz (11), la pompe (9) étant commandée par un moteur électrique (10) qui est mis en marche lorsqu'une vanne de distribution (3) est décrochée de son support (7), le carburant circulant en circuit fermé par l'intermédiaire d'une dérivation (15) jusqu'à l'ouverture de la vanne de distribution (3), caractérisé en ce que la capacité de refoulement de la pompe (9) est commandée au moyen d'un régulateur (22) en fonction du nombre de vannes de distribution (3) décrochées de leur support (7), selon la contribution de ces dernières au volume total refoulé par toutes les vannes de distribution (3) en tenant compte des pertes par refoulement.
  3. Système de distribution selon la revendication 1 ou 2, caractérisé en ce que la capacité de refoulement de la pompe (9) peut être modifiée en jouant sur la vitesse de rotation du moteur électrique (10) qui entraîne la pompe (9).
EP90102372A 1990-02-07 1990-02-07 Système de distribution pour carburants liquides Expired - Lifetime EP0440845B1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP90102372A EP0440845B1 (fr) 1990-02-07 1990-02-07 Système de distribution pour carburants liquides
ES199090102372T ES2042092T3 (es) 1990-02-07 1990-02-07 Dispositivo de surtidor para el suministro de carburantes liquidos.
AT90102372T ATE89533T1 (de) 1990-02-07 1990-02-07 Zapfvorrichtung zur ausgabe fluessiger kraftstoffe.
DE9090102372T DE59001502D1 (de) 1990-02-07 1990-02-07 Zapfvorrichtung zur ausgabe fluessiger kraftstoffe.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP90102372A EP0440845B1 (fr) 1990-02-07 1990-02-07 Système de distribution pour carburants liquides

Publications (2)

Publication Number Publication Date
EP0440845A1 EP0440845A1 (fr) 1991-08-14
EP0440845B1 true EP0440845B1 (fr) 1993-05-19

Family

ID=8203601

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90102372A Expired - Lifetime EP0440845B1 (fr) 1990-02-07 1990-02-07 Système de distribution pour carburants liquides

Country Status (4)

Country Link
EP (1) EP0440845B1 (fr)
AT (1) ATE89533T1 (fr)
DE (1) DE59001502D1 (fr)
ES (1) ES2042092T3 (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE29607736U1 (de) * 1996-04-29 1997-08-28 Tankanlagen Salzkotten GmbH, 33154 Salzkotten Vorrichtung zum Dosieren und Messen von Flüssigkeitsmengen
AU4212399A (en) * 1998-05-29 1999-12-13 Dresser Equipment Group, Inc. Pumping system and method for multiple liquids
SE9902844L (sv) 1999-08-05 2001-02-06 Dresser Wayne Ab Sekundärventil
SE522602C2 (sv) 2000-09-22 2004-02-24 Dresser Wayne Ab Tankningsstation samt sätt för utmatning av flytande bränsle vid sådan
EP3395753A1 (fr) * 2017-04-28 2018-10-31 Wayne Fueling Systems Sweden AB Unité de pompe à carburant pour une unité de distribution de carburant, unité de distribution de carburant pour ravitailler un véhicule et procédé de gestion d'une unité de pompe à carburant pour une unité de distribution de carburant
FR3068687B1 (fr) * 2017-07-07 2020-07-17 Tokheim Uk Ltd Distributeur de carburant avec moteur a deux vitesses et son procede de fonctionnement

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2194843A (en) * 1938-02-25 1940-03-26 Tokheim Oil Tank & Pump Co Liquid dispensing apparatus
DE2405081A1 (de) * 1974-02-02 1975-08-07 Grundstuecksverwaltungsgesells Vorrichtung zum betanken von kraftfahrzeugen
FR2592189B1 (fr) * 1985-12-20 1988-04-01 Zurak Ivica Dispositif de regulation de debit d'une pompe et circuit de distribution de fluide le comportant

Also Published As

Publication number Publication date
DE59001502D1 (de) 1993-06-24
ES2042092T3 (es) 1993-12-01
ATE89533T1 (de) 1993-06-15
EP0440845A1 (fr) 1991-08-14

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