Classifications

• • 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
  • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
  • F02M63/02—Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively
  • F02M63/0205—Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively for cutting-out pumps or injectors in case of abnormal operation of the engine or the injection apparatus, e.g. over-speed, break-down of fuel pumps or injectors ; for cutting-out pumps for stopping the engine
  • F02M63/0215—Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively for cutting-out pumps or injectors in case of abnormal operation of the engine or the injection apparatus, e.g. over-speed, break-down of fuel pumps or injectors ; for cutting-out pumps for stopping the engine by draining or closing fuel conduits
• • 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
  • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
  • F02M63/0012—Valves
  • F02M63/0031—Valves characterized by the type of valves, e.g. special valve member details, valve seat details, valve housing details
  • F02M63/0043—Two-way 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
  • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
  • F02M63/02—Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively
  • F02M63/0225—Fuel-injection apparatus having a common rail feeding several injectors ; Means for varying pressure in common rails; Pumps feeding common rails
• • 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
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/7722—Line condition change responsive valves
  • Y10T137/7738—Pop valves
  • Y10T137/7739—Pop closing valves
• • 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
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/7722—Line condition change responsive valves
  • Y10T137/7738—Pop valves
  • Y10T137/774—Pop pressure reactor in inflow to valve
• • 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
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/7722—Line condition change responsive valves
  • Y10T137/7738—Pop valves
  • Y10T137/7741—Pop pressure reactor in branched released path
• • 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
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/7722—Line condition change responsive valves
  • Y10T137/7837—Direct response valves [i.e., check valve type]
  • Y10T137/7904—Reciprocating valves
  • Y10T137/7922—Spring biased

Definitions

• the present invention applies to a pressure limiter that can be used in a high-pressure fluid circuit to limit the pressure in the event of failure of one of the components of the circuit. It is in fact a pressure relief valve used for example in common rail fuel injection systems.
• the device has in this case a function of safety and protection of the system by reducing the pressure in case of malfunction of one of the control components (injector, pressure sensor, flow regulator).
• the pressure relief valve is subjected to the high pressure of the injection system, that which exists inside the common rails used for injection into the engines. This pressure can range from 200 to 2000 bars depending on the systems.
• This type of discharge valve is conventionally constituted by a jacket, forming the outer casing, inside which slides a pusher axially biased by return means and actuating means for closing off an orifice communicating in certain conditions an upstream chamber for admission of the high-pressure fluid with an exhaust downstream chamber.
• the downstream chamber then comprises at least one exhaust opening of the fluid, for example to the vehicle tank.
• This threshold is determined by the use of biasing means of suitable caliber.
• the sealing means generally consist of a ball which closes a conical seat formed in the pierced wall of the communication orifice between the chambers, the ball being then pressed against said seat by the action of the spring on the pusher.
• the ball moves and in principle allows the limitation of the pressure by discharging the excess flow to the downstream chamber, then exhausting to a reservoir.
• the pusher has a protrusion allowing it to exert an action on the ball. In the closed position, this protrusion is moreover planned in length such that the or the exhaust openings of the fluid existing in the downstream chamber are not covered by the pusher, leaving these openings fully functional in all circumstances.
• the pusher further comprises axial flats allowing the passage of fluid to the opposite side of the pusher, the one on which the spring acts.
• this device is a safety device, supposed to limit the increase in pressure to avoid damaging the system components. In order for it to perform its function correctly, it would therefore be necessary that, when the closure means open, the pressure decreases or, at worst, remains constant.
• the present invention proposes to overcome this disadvantage, and to promote a solution to achieve a real decrease in the value of the pressure in the high pressure circuit when the discharge valve is open.
• the constructive arrangement which is the subject of the invention allows for this effect a compensation of the hydrodynamic effect which was not taken into account in the previous devices. This compensation is mainly aimed at reducing the pressure gradient when the flow rate to be discharged increases.
• the pusher is devoid of axial passageways for the fluid and slides with a small functional clearance in the liner. It is further dimensioned to at least partially obstruct each exhaust opening, at least one of which is connected to an opening also made in the jacket and opening at least partially to the opposite side of the pusher, so as to provide a back pressure.
• the covering of the exhaust openings creates a hydraulic restriction to the rights of said openings. And, under the effect of the discharge rate, this restriction and the absence of passageways in the pusher creates an overpressure in the downstream chamber, which acts on the pusher and decreases the action of the spring depending on the intensity flow.
• the increase in pressure in the high-pressure circuit is thus controlled in the direction of a limitation when the flow rate increases.
• the pressure limiter of the invention comprises closure means consisting of a ball housed in a hemispherical seat whose bottom is pierced with the communication port between the upstream and downstream chambers.
• the ball also cooperates with an extension protruding axially from the pusher and which exerts an axial direction action on it.
• the hemispherical seat is in fact disposed at the bottom of an axial well opening into the downstream chamber, which extends the orifice connecting the chambers and is adapted to accommodate the projection protruding from the pusher.
• the axial protrusion protruding from the pusher and the ball are in one piece.
• the upstream chamber, the orifice connecting the upstream and downstream chambers, and the seat of the closure means are arranged in a single piece closing one end of the jacket.
• This part manufactured separately, is simply attached to one end of the jacket, obstructing the bore in which the slide pushes.
• the return means consist of a compression spring.
• the ends of the spring are fixed on two axial studs respectively protruding from the pusher and a plug closing the end of the sleeve opposite the high pressure chamber.
• said cap obeys the same logic as the part in which the seat of the ball is made.
• the downstream chamber has two exhaust openings, as already mentioned, which make it possible to return the fluid discharged from the high-pressure circuit to for example a fuel tank.
• FIG. 1 represents the general diagram of a fuel injection system equipped with a pressure limiter according to the invention
• FIG. 2 shows a limiter of the prior art, with an enlargement of the ball shutter and its seat
• FIG. 3 represents the curve of the pressure in the high-pressure circuit as a function of the flow rate obtained with such a configuration
• - Figure 4 is a sectional view of the configuration which is the subject of the present invention.
• FIG. 5 represents the curve of pressures as a function of flow rates obtained with this new configuration.
• the common rail (20) containing the injectors (21) is supplied with fuel by a high pressure pump (22) extracting the essence of a tank (23) via a solenoid valve (24). input flow control.
• a pressure sensor (25), also arranged in the common rail (20), is connected to an electronic central unit (26) which controls in particular the solenoid valve (24).
• the system pressure is limited, in the event of failure of one of the circuit control components, by discharging the flow to the return drain of the pump (22). This discharge is done in the pressure limiter (27) which constitutes the invention.
• the fuel thus evacuated is returned to a reservoir (28).
• the pressure limiter (27) is in this case a purely mechanical component. Those used today, an example of which is shown in FIG.
• a jacket (4) forming the outer casing of the limiter, and provided with a central bore in which a pusher (3) can slide. It is closed at its ends on the one hand by a part (1) at which is made the connection to the high-pressure circuit, and secondly by a plug (6).
• the seat (8) of the ball (2) flares towards a chamber (10) downstream delimited by the inner wall of the part (1), one side of the pusher (3) and the inner wall of the sleeve (4). ).
• the ball (2) which acts as a sealing means, is pressed against its seat (8) by an axial protrusion (11) protruding from the pusher (3).
• this protrusion (11) has a length such that the axial dimension of the downstream chamber (10) thus created is sufficient to prevent the openings of exhaust (12, 12 ') by the pusher (3).
• the equilibrium state in the closed position results from the existence of a spring (5) which recalls the pusher (3), and consequently the ball (2), in the closed position.
• This spring (5) is centered at its two ends respectively to the pusher (3) and the plug (6) by axial studs (13, 14) which protrude.
• X b lifting of the ball
• P rai system pressure
• the major changes concern the pusher (3), the positioning of the seat (8) and the existence of an additional opening (15) in the body of the jacket (4).
• the pusher (3) now devoid of axial passages for the fluid, is further dimensioned so that, when it holds the ball (2) against its seat (8), it impinges on the surfaces of the openings (12). , 12 '), thus creating a hydraulic restriction to the rights of these openings. Under the effect of the discharge rate, an overpressure is created in the chamber (10).
• the opening (15), connected to at least one of the openings (12, 12 '), imposes on the side of the pusher (3) at which it opens a pressure identical to the pressure of the exhaust fluid as it is located at the openings (12, 12 ').
• the two opposite cross sections of the pusher (3) therefore receive a different pressure. This differential creates on the pusher (3) a force that tends to oppose the action of the spring, and reduces, depending on the discharge rate, the load of the spring (5) on the ball (2).
• the force received by the ball (2) of the pusher (3) is: F R0 + K R x X b - P A (Q) x S p
• the displacement of said pusher (3) can be substantially greater than in the versions of the prior art.
• its seat (8) was then placed at the bottom of a well (16) which guides and centers surplus the protrusion (11) protruding from the pusher (3) at the time of the making.
• the protrusion (11) prevents in any case the output of the ball (2).
• the configuration of the invention allows in particular a significant reduction in the dimensions of the limiter of the invention. However, it is only one possible example of implementation of the invention.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Safety Valves (AREA)
• Mechanical Operated Clutches (AREA)
• Valve Device For Special Equipments (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=35784708

Family Applications (1)

Country Status (6)

Families Citing this family (7)

Family Cites Families (12)

• 2005
  • 2005-06-15 FR FR0506064A patent/FR2887319B1/fr not_active Expired - Fee Related
• 2006
  • 2006-06-13 EP EP20060764780 patent/EP1902214B1/de not_active Not-in-force
  • 2006-06-13 AT AT06764780T patent/ATE511603T1/de not_active IP Right Cessation
  • 2006-06-13 WO PCT/FR2006/001331 patent/WO2006134264A1/fr active Application Filing
  • 2006-06-13 CN CN2006800216601A patent/CN101313143B/zh not_active Expired - Fee Related
  • 2006-06-13 US US11/922,081 patent/US8245725B2/en not_active Expired - Fee Related

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events