[go: up one dir, main page]

WO2019110282A1 - Dispositif d'alimentation en carburant destinée à des carburants cryogéniques - Google Patents

Dispositif d'alimentation en carburant destinée à des carburants cryogéniques Download PDF

Info

Publication number
WO2019110282A1
WO2019110282A1 PCT/EP2018/081693 EP2018081693W WO2019110282A1 WO 2019110282 A1 WO2019110282 A1 WO 2019110282A1 EP 2018081693 W EP2018081693 W EP 2018081693W WO 2019110282 A1 WO2019110282 A1 WO 2019110282A1
Authority
WO
WIPO (PCT)
Prior art keywords
piston
fuel delivery
delivery device
pump
pressure line
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.)
Ceased
Application number
PCT/EP2018/081693
Other languages
German (de)
English (en)
Inventor
Andreas Kellner
Dirk SCHNITTGER
Andreas Beiter
Friedrich Howey
Martin Katz
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.)
Robert Bosch GmbH
Original Assignee
Robert Bosch 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 Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of WO2019110282A1 publication Critical patent/WO2019110282A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B9/00—Piston machines or pumps characterised by the driving or driven means to or from their working members
    • F04B9/08—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid
    • F04B9/10—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid
    • F04B9/103—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having only one pumping chamber
    • F04B9/107—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having only one pumping chamber rectilinear movement of the pumping member in the working direction being obtained by a single-acting liquid motor, e.g. actuated in the other direction by gravity or a spring
    • F04B9/1076—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having only one pumping chamber rectilinear movement of the pumping member in the working direction being obtained by a single-acting liquid motor, e.g. actuated in the other direction by gravity or a spring with fluid-actuated inlet or outlet valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
    • F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
    • F02M21/0218—Details on the gaseous fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
    • F02M21/0245—High pressure fuel supply systems; Rails; Pumps; Arrangement of valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
    • F02M59/02—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type
    • F02M59/10—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type characterised by the piston-drive
    • F02M59/105—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type characterised by the piston-drive hydraulic drive
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/22—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00 by means of valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B15/00—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts
    • F04B15/06—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts for liquids near their boiling point, e.g. under subnormal pressure
    • F04B15/08—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts for liquids near their boiling point, e.g. under subnormal pressure the liquids having low boiling points
    • F04B2015/081—Liquefied gases
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/30—Use of alternative fuels, e.g. biofuels

Definitions

  • the invention relates to a fuel delivery device for cryogenic fuels having the features of the preamble of claim 1.
  • natural gas NG
  • LNG liquefied natural gas
  • a piston pump for cryogenic fuels, in particular for natural gas, with a reciprocating pump piston is known.
  • the pump piston limits a pump working space, which can be filled with liquid natural gas, so that in the pump working space existing liquid natural gas can be acted upon by a lifting movement of the pump piston with high pressure.
  • At the other end of the pump piston limits a drive space which can be filled with a hydraulic pressure medium to drive the pump piston in a reciprocating motion.
  • an electric, pneumatic or mechanical drive is proposed.
  • the present invention seeks to provide a fuel delivery device for cryogenic fuel materials with a designed as a piston pump high-pressure fuel pump, which is hydraulically driven and has increased dynamics.
  • the fuel delivery device with the features of claim 1 is proposed.
  • Advantageous developments of the invention can be found in the dependent claims.
  • the proposed fuel delivery device for cryogenic fuels comprises a piston pump for delivering the cryogenic fuel to high pressure, the Kol benpumpe has a reciprocating pump piston, on the one hand egg nen compression chamber and on the other hand limited acted upon by a hydraulic pressure medium drive space.
  • the drive space can be alternately connected to a high-pressure line and a low-pressure line via a hydraulically pilot-operated directional control valve.
  • the drive space fills with the hydraulic pressure medium, so that a hydraulic pressure force acts on the pump piston, which drives the pump piston to a delivery stroke.
  • a connection to the low-pressure line is established, so that no more hydraulic pressure medium flows into the drive chamber, the return of the pump piston can be effected in the suction operation of the piston pump. In this case, pressure fluid flows from the drive chamber into the low-pressure line.
  • the provision of the pump piston can be effected mechanically, hydraulically or pneumatically.
  • a directional control valve which is hydraulically piloted, allows with comparatively low forces as a quick pressurization or discharge of the drive chamber of the piston pump. In this way, fast and at the same time precise movements of the pump piston can be realized. At the same time a high pumping frequency of the piston pump is achieved. The high pumping frequency in turn made it possible to reduce the stroke and / or the diameter of the pump piston so that the efficiency of the fuel delivery device is increased.
  • the hydraulically pre-controlled directional control valve is a 3/2-way valve.
  • the directional control valve has three Has conclusions and two switch positions.
  • a first connection the directional control valve is connected to the drive chamber of the piston pump.
  • a further connection serves to connect the directional control valve to the high-pressure line or to the low-pressure line.
  • the first connection is connected to the high-pressure line or the low-pressure line.
  • the hydraulically piloted directional control valve comprises a rule in a sleeve between two switching positions reciprocally recorded spool, which limits directly or indirectly via a pilot piston a control chamber which is connected to the high pressure line and pressure line via a control valve with the low is connectable.
  • the control valve When the control valve is closed, there is high pressure in the control chamber, which acts as control pressure (directly or indirectly via the pilot piston) on the spool. If the control valve is opened, hydraulic pressure medium flows from the control chamber into the low pressure line and the spool piston is relieved so that it can move in the direction of the control chamber.
  • the control valve Compared to the opening cross sections of the directional valve, the control valve only has to provide a small opening cross section, so that the stroke of the Steuerven tils can turn out small. In this way, high switching speeds can be realized with comparatively low forces.
  • the forces can be provided by a corre sponding small actuator, which may be in particular a Mag netaktor or a piezoelectric actuator.
  • the hydraulically piloted directional control valve can be integrated into a housing part of the piston pump or - with its own housing - mounted on the piston pump. In both cases, a compact structure arrangement can be achieved.
  • the mitels the control valve relieved control chamber is preferably connected via a throttle to the high pressure line, so that the feed is throttled into the control room. This ensures that with the opening of the control valve less Druckmitel flows into the control chamber than flows out and the required relief is effected.
  • the connection of the control chamber to the low-pressure line he preferably follows via an outlet throttle to keep the tax amounts as low as possible.
  • the throttle cross section of the outlet throttle is greater than the throttle cross section of the inlet throttle to choose so that it comes to the aforementioned discharge.
  • the tuning of the Drosselquerschnite is also known from the Injektortechnik.
  • the slide piston is permanently subjected to high pressure on the side facing away from the control chamber.
  • the directional valve thus acts on the spool a hydraulic force which acts on the spool in the direction of the control chamber. If the control valve ge opens, so that the control pressure in the control chamber drops, the force acting on the control piston piston on the side facing away from the control hydraulic force causes the spool moves in the direction of the control chamber. If the control valve is then closed again, high pressure builds up again in the control chamber, so that a pressure equilibrium prevails.
  • the area ratio of the hydraulically active surfaces is selected such that acts on the spool a restoring force resulting.
  • the control chamber can be limited by a pilot piston having a larger diameter than the slide piston.
  • the spool acts on the remote from the control room Be te with a valve seat together. If the spool is returned to the valve seat by the control pressure prevailing in the control chamber, the spool seals the connection to the high-pressure line. In this way, a higher density is achieved, which counteracts leakage from the high pressure area in the Niederbuchbe rich on an outer peripheral side control edge.
  • the valve seat also defines an end position of the spool.
  • the valve seat is formed by egg nen valve seat body, which is inserted into the sleeve of the directional control valve, for example, pressed, is.
  • the pilot piston has a shoulder which cooperates with a housing-side stop. About the stop a wide re end position of the spool can be defined.
  • the pump piston of the piston pump is acted upon by a hydraulic force that drives the pump piston to a delivery stroke. If the drive space is subsequently connected to the low-pressure line, this alone does not lead to a return of the pump piston.
  • the provision requires further measures or funds.
  • One possibility of the return be about the prefeed pressure of the cryogenic fuel. This generates a restoring force, which is so small that the necessary dynamics of the overall system are insufficient.
  • the pump piston of the piston pump is alsschlagt be in the direction of the drive chamber by the spring force of a compression spring.
  • the provision of the pump piston is effected mechanically in this case, which can be implemented particularly easily and inexpensively.
  • the piston pump is connected via the high-pressure line to the pressure side of a hydraulic pump, so that it can be built up in the high-pressure line via the hydraulic pump of the required pressure.
  • the hydraulic pump can be performed in example also as a piston pump.
  • the drive of the hydraulic pump can be done in this case via a camshaft, which is coupled to the engine Brennkraftma. Instead of a cam drive and a crank mechanism for driving the hydraulic pump can be used.
  • the hydraulic pressure medium may be, for example, an oil, in particular an engine oil.
  • the hydraulic pressure medium can thus be used at the same time as a lubricant.
  • the piston pump via the low-pressure line with a return line and / or a tank for storing the hydraulic pressure medium a related party.
  • the hydraulic pressure medium can be returned in this way directly or indirectly via the return line into the tank, so that a cycle is created. At the same time a leakage amount of the piston pump can be returned to the tank via the return line.
  • FIG. 1 is a schematic longitudinal section through a fuel device according to the invention in accordance with a preferred embodiment
  • Fig. 3 is an enlarged view of the hydraulic pilot control of Wegeven tils of Figures 1 and 2.
  • the fuel delivery device according to the invention shown in FIG. 1 is used to supply an internal combustion engine (not shown) of a motor vehicle with egg nem cryogenic fuel, which may in particular be natural gas.
  • the fuel delivery device comprises a piston pump 1, by means of which the fuel is conveyed to high pressure.
  • the piston pump 1 has a reciprocating pump piston 2 which delimits a compression space 3 in which the fuel is compressed. Via an inlet 24, the compression chamber 3 can be filled with fuel.
  • the compressed fuel leaves the compression chamber 3 via a high pressure outlet 25, in which a check valve 26 is formed.
  • the pump piston 2 of the piston pump 1 limits the other end a drive chamber 4, which is connected via a hydraulically piloted directional control valve 5 alternately with a high pressure line 6 and a low pressure line 7.
  • the fuel delivery device shown in FIG. 1 further comprises a hydraulic pump 18, which promotes the hydraulic pressure fluid from a tank 20 in the direction of the directional control valve 5.
  • the hydraulic pump 18 fills a device 6 arranged in the Hochdrucklei intermediate memory 19 which prevents a pressure drop in the high-pressure line 6 with variable quantity removed.
  • the low pressure line 7 is connected via a return line 21 to the tank 20, so that a hydraulic circuit is created running.
  • the hydraulically piloted directional control valve 5 is shown enlarged in FIG.
  • the directional control valve 5 is shown in a first switching position, which leads to a high pressure loading of the drive chamber 4 of the piston pump 1, so that the pump piston 2 performs a delivery stroke.
  • the directional control valve 5 is shown in a second switching position in which a compound of the drive chamber 4 with the low pressure line 7, so that the penkolbens 2 for mechanical recovery of Pum required relief of the drive chamber 4 is effected.
  • the directional control valve 5 is designed as a 3/2-way valve and has a reciprocatingly received in a sleeve 8 slide piston 9, on the - in speed depending on the respective switching position - a connection of the drive chamber 4 with the high-pressure line 6 or with the Low pressure line 7 can be produced.
  • the Schieberkol ben 9 is coupled to a pilot piston 10 which limits a control chamber 11.
  • the control chamber 11 is connected to the high-pressure line 6 via an inlet throttle 13. closed, so that when the control valve 12 is closed in the control chamber 11 high pressure prevails. If, however, the control valve 12 is opened, a connection of the control chamber 11 to the low-pressure line 7 is produced via an outlet throttle 14, so that the control pressure acting on the pilot piston 10 decreases rapidly.
  • the pilot control piston 10 and the slide piston 9 thus move upwards (see FIG. 2 a).
  • Spool 9 is thereby a valve seat 15 free, which is formed by a set in the sleeve 8 a valve seat body 16, so that hereby a connection of the drive chamber 4 is made to the high-pressure line 6.
  • the pump piston 2 of the piston pump 1 moves down accordingly. Is the provision of the pump piston 2, the control valve 12 is closed again, builds on the inlet throttle 13 again high pressure in the control chamber 11, the control piston 10 a finally the spool 9 due Erkilben 10 due to the area ratios of the pilot and formed on the spool 9 hydraulically effective Press surfaces down again until the spool 9 again comes to rest on the valve seat 15 (see Fig. 2b).
  • FIG. 3 A more detailed representation of the control valve 12 is shown in FIG. 3.
  • the pilot piston 10 is partially received in a guide sleeve 27, in which the control chamber 11 is formed.
  • the guide sleeve 27 also forms a valve seat 28 for a spherical valve closing element 29 of the control valve 12, into which the outlet throttle 14 opens.
  • the pilot piston 10 ei ne shoulder 22, which cooperates with a housing-side stop 23.
  • the upper end position of the spool 9 is defined.
  • the lower end position is predetermined by the valve seat 15 of the directional control valve 5.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Details Of Reciprocating Pumps (AREA)

Abstract

L'invention concerne un dispositif d'alimentation en carburant destiné à des carburants cryogéniques, comprenant une pompe à piston (1) servant à refouler le carburant cryogénique à haute pression, la pompe à piston (1) présentant un piston (2) qui peut être animé d'un mouvement alternatif et qui délimite d'une part une chambre de compression (3) et d'autre part une chambre d'entraînement (4) pouvant être soumise à l'action d'un fluide hydraulique sous pression. Selon l'invention, la chambre d'entraînement (4) peut être reliée tour à tour à une conduite haute pression (6) et à une conduite basse pression (7) par l'intermédiaire d'un distributeur (5) à commande hydraulique.
PCT/EP2018/081693 2017-12-07 2018-11-19 Dispositif d'alimentation en carburant destinée à des carburants cryogéniques Ceased WO2019110282A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102017222204.2 2017-12-07
DE102017222204.2A DE102017222204A1 (de) 2017-12-07 2017-12-07 Kraftstofffördereinrichtung für kryogene Kraftstoffe

Publications (1)

Publication Number Publication Date
WO2019110282A1 true WO2019110282A1 (fr) 2019-06-13

Family

ID=64426900

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2018/081693 Ceased WO2019110282A1 (fr) 2017-12-07 2018-11-19 Dispositif d'alimentation en carburant destinée à des carburants cryogéniques

Country Status (2)

Country Link
DE (1) DE102017222204A1 (fr)
WO (1) WO2019110282A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2541062A1 (fr) 2011-06-29 2013-01-02 Westport Power Inc. Pompe cryogène
WO2017004305A1 (fr) * 2015-07-01 2017-01-05 Caterpillar Inc. Procédé de fonctionnement de pompe cryogénique et système de pompe cryogénique
WO2017034743A1 (fr) * 2015-08-24 2017-03-02 Caterpillar Inc. Système d'entraînement hydraulique pour pompe cryogénique
US20170335834A1 (en) * 2016-05-23 2017-11-23 Caterpillar Inc. Pump for fluid system and method of operating same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2541062A1 (fr) 2011-06-29 2013-01-02 Westport Power Inc. Pompe cryogène
WO2017004305A1 (fr) * 2015-07-01 2017-01-05 Caterpillar Inc. Procédé de fonctionnement de pompe cryogénique et système de pompe cryogénique
WO2017034743A1 (fr) * 2015-08-24 2017-03-02 Caterpillar Inc. Système d'entraînement hydraulique pour pompe cryogénique
US20170335834A1 (en) * 2016-05-23 2017-11-23 Caterpillar Inc. Pump for fluid system and method of operating same

Also Published As

Publication number Publication date
DE102017222204A1 (de) 2019-06-13

Similar Documents

Publication Publication Date Title
DE102004013307B4 (de) Kraftstoffhochdruckpumpe mit einem Druckbegrenzungsventil
DE102008045730B4 (de) Rücklauffreie Kraftstoffpumpeneinheit sowie damit ausgerüstetes Fahrzeug
DE102011075259B4 (de) Überdruckventil und hochdruckpumpe mit einem solchen ventil
DE112006003076T5 (de) Brennstoffsystem mit mehreren Quellen für Einspritzung mit variablem Druck
DE602004011229T2 (de) Common-rail-kraftstoffpumpe
DE102008057089A1 (de) Pumpeneinheit für eine Hochdruckpumpe
EP1357283B1 (fr) Dispositif d'injection de carburant pour un moteur à combustion interne
DE102009045113A1 (de) Druckbegrenzungseinrichtung
DE112009001971T5 (de) Rückschlagventil mit separater kugelförmiger Federführung
WO2007073985A1 (fr) Pompe a haute pression, en particulier pour dispositif d'injection de carburant d'un moteur a combustion interne
EP0752061B1 (fr) Systeme permettant d'injecter du carburant dans les cylindres d'un moteur a combustion interne
DE10139055A1 (de) Verfahren, Computerprogramm, Steuer- und/oder Regelgerät sowie Kraftstoffsystem für eine Brennkraftmaschine
DE10153189A1 (de) Kraftstoffpumpe, Kraftstoffsystem, Verfahren zum Betreiben eines Kraftstoffsystems sowie Brennkraftmaschine
EP2659125B1 (fr) Dispositif de regulation de pression d'un système d'injection de carburant ayant une soupape arrange du côté pression de la pompe
WO2005124153A1 (fr) Pompe haute pression conçue pour un dispositif d'injection de carburant d'un moteur a combustion interne
DE102009001266A1 (de) Kraftstoff-Injektor mit piezoelektrischem Aktuator sowie hydraulischem Koppler
WO2019110189A1 (fr) Dispositif d'alimentation en carburant destinée à des carburants cryogéniques
WO2019110282A1 (fr) Dispositif d'alimentation en carburant destinée à des carburants cryogéniques
DE102008040452A1 (de) Zweistufige Hochdruckpumpe
DE102008002101A1 (de) Radialkolbenpumpe
WO2019149472A1 (fr) Dispositif d'alimentation en carburant pour carburants cryogéniques
DE957699C (fr)
DE102018203769A1 (de) Kraftstofffördereinrichtung für kryogene Kraftstoffe
DE102004054589A1 (de) Steuerventil und Einspritzventil
DE102009002487A1 (de) Hochdruckpumpe

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18807264

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18807264

Country of ref document: EP

Kind code of ref document: A1