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
  • F02M63/0001—Fuel-injection apparatus with specially arranged lubricating system, e.g. by fuel oil
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
  • F01M1/00—Pressure lubrication
  • F01M1/02—Pressure lubrication using lubricating pumps
• • 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
  • F02M59/102—Mechanical drive, e.g. tappets or cams

Definitions

• the present invention relates to a piston pump intended to supply two independent liquid circuits, in particular the fuel injection circuit and the lubrication circuit of an internal combustion engine. It is more particularly a through shaft pump.
• injection and lubrication functions are performed conventionally by two separate devices.
• lubrication it is provided on the engines by means of an oil pump, which pump is driven directly or by means of pinions by the rotational movement of the crankshaft.
• injection pump On the other hand, the fuel supply to each cylinder, or injection, is ensured by a so-called “injection” pump.
• this pump includes a plurality of pistons driven by a camshaft and returned by springs. The spring return notoriously limits the maximum speed of the pump, absorbs a lot of power, makes a lot of noise and overheating.
• injection and lubrication are provided by two separate organs, which increases the total cost, and above all limits accessibility.
• the invention proposes to provide a pump which jointly performs the functions of an oil pump for the lubrication of an engine and an injection pump for the supply of fuel to the same engine.
• the invention relates to a device consisting of two piston pumps intended to supply two independent liquid circuits, in particular the fuel injection circuit and the oil circuit for internal combustion engines, characterized in that it comprises:
• each injection pump piston cooperating for the thrust and the return with an eccentric by means of a half-ring whose opening is directed towards the corresponding oil pump piston, and the ends of said half-ring respectively comprising a piston guide and a piston rod, the rod and the guide being placed in the extension of each other, each piston rod sliding in a cylinder comprising a light which defines the start of injection with one end of the rod in the form of an inclined ramp and the end of injection with a hole made on the rod.
• It also includes a one-piece injection cylinder head connecting all the cylinders by blocking on the one-piece casing;
• Each cylinder is movable inside a cylinder cover whose position relative to the cylinder is adjusted by a screw;
• the one-piece injection cylinder head comprises, opposite the cylinder, a compression chamber receiving the valve and its spring, and leading to the departure of two injectors;
• the housing includes a cover fixed on the rest of the housing and which includes a slide and a light capable of letting the finger pass from the rack towards the regulator;
• - the rack finger is controlled by a speed regulator fixed on the housing cover;
• - the inclined ramp of the rod, the hole made on the rod, and the lumen of the cylinder, are arranged in such a way that the injection takes place on either side of the mid-stroke of the piston, when its linear speed is the largest;
• one end of the eccentric shaft can be connected directly to the crankshaft, while the other end can receive a pulley to drive additional equipment such as a water pump or alternator.
• the oil pump body and the injection pump bodies are arranged perpendicularly to each other on the outside of the same casing filled with fuel which serves as a housing for the eccentric shaft which controls them together and with the same eccentrics.
• the oil pump pistons are returned with compression springs while the injection pump piston drive is of the desmodromic type by means of a half-ring terminated at its ends by two internal bearing elements, flat, perpendicular to the movement of the piston and intended to be in contact with the eccentric.
• a rod corresponds to each internal bearing: for one side, it is the pump piston and for the other, it is a guide which ensures perfect guidance of the monobloc assembly constituted by the half-ring and the two rods .
• the casing which receives all the pump bodies is in two parts: the first part constitutes the body of the casing and it serves essentially as housing for the eccentric and the half-rings of the injection pump pistons.
• the injection pistons are mounted at an angle from the opening and the position of the pistons is given by the housing of the injection piston guides in the housing. In contrast, the position of the injection cylinders on the housing is given by the piston and from the guide.
• the hole in the housing around the injection piston has a very large clearance to facilitate assembly and to allow the return of uninjected fuel at the end of injection. This return takes place between the cylinder and the cylinder cover and through cross-shaped slots under the cylinder towards the hole in the casing around the piston.
• the position of the cylinders on the casing is given by the pistons using the guide mounted with very little play in its housing at the bottom of the casing.
• the cylinder covers are made integral with the cylinders by two screws which also serve to make them turn slightly on themselves when the pump is adjusted on the test bench, to have an angularly identical start of injection on all the pistons. .
• This adjustment is made with the cylinder head slightly unlocked to release the cylinders which are sealed without a seal and the cylinder covers which are sealed with two O-rings.
• One O-ring seals with the housing and the other with the cylinder head.
• the cylinder head is a distribution part common to all the injection cylinders. This arrangement ensures better rigidity and stability of the assembly.
• each piston corresponds to a conical chamber which receives the ball valve with its return spring. The ball has its seat directly in the cylinder.
• two outlets are machined to communicate with two injectors, not shown, which in turn supply fuel to an engine cylinder or an explosion chamber. This arrangement is remarkable and the distribution is equal in volume over the two injectors with the same injection pressure setting.
• the flow rate of the injection pump is variable while the engine is running. This variation in flow is obtained by an inclined ramp at the piston head. This inclined ramp closes an orifice on the piston cylinder. By rotating the piston on itself, we change the position of this closure and as a result, we inject more or less fuel.
• the volume of fuel injected by a piston rise is between a closure, given by the inclined ramp which puts the volume under pressure, and an opening which puts the volume in flight and which corresponds to the end of injection.
• the end of injection is a point which always remains fixed.
• the start of injection is a point which varies with the inclined ramp; the more the closure is advanced in the rise of the piston, the greater the flow, the more the closure is moved back in the rise of the piston, the smaller the flow.
• This variation in flow is given by the rotation of the piston on its axis to change the position of the inclined ramp relative to the light on the pump cylinder.
• This light controls by one end the start of injection and by the other end the end of injection.
• the control of rotation of the pump piston on its axis is obtained by a needle which is welded on the half-ring of each piston.
• This needle is perfectly parallel at constant distance from the axis of the piston. This needle meshes with the rack which simultaneously controls all the pistons.
• the stroke of the injection pump pistons is fixed and the variation in flow rate is given by varying the point of injection start over the stroke of the piston, as is the case with many injection pumps.
• the stroke of the oil pump pistons is the same as that of the injection pump pistons, but the flow is constant for a given speed.
• the variation of the injection pump flow is done by an electronic regulator which avoids the runaway of the engine.
• the electronic regulator which is placed on the side of the pump, in turn controls the rack which in turn controls the rotation of the pistons to vary the flow.
• the second part of the housing is formed by a cover which serves as a housing for the rack. This arrangement is remarkable because:
• the rack housing is very easy to machine with precision; - The mounting of the rack in its housing and on the needles which make the connection between the rack and the pistons, is done very easily by closing the housing with a few locking screws of the two parts of the housing.
• an electronic speed regulator is attached.
• This regulator is placed behind the rack and they are connected together by a finger which is part of the rack and which is housed in the regulator.
• the rack finger is perpendicular to the back of the rack and is located in the middle of the back of the rack.
• the oil pump bodies are placed without adjusting the flow rate. They suck in and discharge over the entire travel of the eccentric with damping of the speed at top and bottom dead centers, which allows operation with return spring even at high speed.
• the piston heads and oil pump cylinders are independent and the circuit is independent on each cylinder. The operation of the injection pistons is remarkable because the injection occurs with the use of a small part of the stroke.
• This part of the stroke used for injection is located on either side of the mid-stroke of the injection piston in the period when the linear speed is the greatest.
• the rest of the stroke causes leaks which return to the crankcase through the light and the notches on the cylinder of the injection pump piston.
• the free volume between the cylinder and the cylinder cover also participates in the fuel return circuit to the crankcase and this is the role of the cylinder cover.
• the injection device itself is of the drawer type.
• the piston head is cylindrical and hollow.
• the central hole connects the compression chamber with a radial hole which opens with the stroke of the piston in a hole on the cylinder.
• On the piston head there is an inclined ramp which regulates the start of injection with regard to the same light on the cylinder.
• the start of injection is a moving point which varies with the position of the inclined ramp at the piston head.
• the pump Once the pump has been adjusted to the bench, it can be mounted directly at the end of the crankshaft on the engine.
• Figure 1 is a perspective view of the eccentric shaft fitted with injection pump pistons.
• Figure 2 is a side view of an injection pump piston.
• Figure 3 is a top view of the same piston.
• Figure 4 is an enlarged detail of the head of the piston rod.
• Figure 5 is a general section along a plane perpendicular to the eccentric shaft.
• the invention combines an oil pump and an injection pump used in particular in a diesel engine, the number of pistons of this pump is not limited.
• This assembly comprises an eccentric through shaft (10), a set of pistons (20) of oil pump of cylindrical shape with valves, and a set of pistons (30) of injection pump having the general form of a half-ring (31), carrying at its ends a piston rod (32) and a guide (33) coaxial.
• This assembly is trapped in a casing (15) not shown in FIG. 1.
• the oil pump pistons (20) slide inside the oil pump cylinders (21) fixed by a cylinder head (22) not shown in this figure.
• the injection pump piston guides slide inside the same casing (15).
• the injection pump piston rods (32) slide, in their end part, in a piston cylinder (35) surrounded by a cylinder cover (36) and surmounted by an injection cylinder head (37) not shown.
• FIG. 5 the different parts are better identified in the assembled state.
• the eccentric shaft (10) (11) comprising as shown (1) an eccentric (11).
• an oil pump piston (20) of a hollow cylindrical shape, shown here in the position closest to the axis (12) of rotation.
• This piston can slide inside a piston cylinder (21), the sending being generated by the movement of the eccentric (11) and the return (in this maximum figure) is ensured by a spring (23) .
• the chamber of this piston communicates with a cylinder head (22) equipped with valves not shown ensuring the passage of the oil according to the arrows referenced.
• the injection pump piston (30) moves in a direction perpendicular to the oil pump piston (20).
• This piston (30) is composed of three separate portions, namely a piston rod (32), a half-ring (31) for driving and connecting, and a guide (33).
• the piston rod (32) moves inside a piston cylinder (35) to cause the compression of a quantity of fuel and send it into the cylinder head (37) and up to the injector at through a ball valve (38).
• This piston rod (32) is pierced with an axial hole (40) connected in the axis of the half-ring (31) by a radial hole (42) which opens onto the diameter of the piston and which controls the end of injection when it leads to the light (45) of the cylinder.
• the cylinder (35) is sealed with a cylinder cover (36). They are made integral by a screw (46). This screw (46) is used to change the position of the cylinder on the test bench and unlocked cylinder head (37) to angularly obtain the same start of injection on all the pistons for the same arbitrary position of the rack.
• the cylinder cover (36) is used to contain leaks at the end of injection towards the casing according to arrow F.
• the piston guide (33) is placed in the extension of the piston rod (32) on the other side of the eccentric shaft (10).
• This guide (33) is slidably mounted inside the casing (15).
• the guide (33) and the rod (32) are connected by a half-ring (31) whose internal shape cooperates with the eccentric (11).
• the eccentric (11) rotates
• the most eccentric part (13) of the axis (12) of rotation of the shaft sometimes pushes the rod (32) to ensure the compression movement and the sending the piston, sometimes push the guide (32) to ensure the piston returns.
• This advantageous form makes it possible to dispense with the use of a return spring.
• the half-ring (31) carries on its external face (50) an axis parallel (51) to the axis of the movement of the piston and is separated from the external face (50) of the half-ring (31) by two arms ( 52.53).
• This axis (51) is intended to be translated by a recess (55) on the rack (56) driven by a speed regulator (57).
• a speed regulator 57
• this rack 56) makes it possible to pivot the piston (30) about its axis of alternating movement.
• the various pistons (30) placed along the eccentric shaft (11) are driven simultaneously by this speed regulator (57) and by the rack (56).
• the eccentric shaft (11) rotates on itself, causing a longitudinal reciprocating movement of the oil pump piston (20) which thus ensures its function.
• the piston (30) of the injection pump also describes a reciprocating longitudinal movement which allows it to create the compression of the fuel at the level of the compression chamber which is located under the ball valve placed on the cylinder ( 35).
• the head (41) of the piston rod (32) is opposite the light (45) located on the piston cylinder (35).
• the entire casing, the space between the cylinder cover (36) and the cylinder (35), the cylinder light (45) and the interior (40) of the piston rod are in communication, therefore at low pressure.
• the piston rod (32) begins its movement inside the cylinder (35) and the head (41) of the rod leaves the light (45) of the piston cylinder (35). From this moment, the fuel trapped inside (40) of the piston rod and below the valve (38), is compressed. Then, the movement of the piston (30) continuing in the same direction, the hole (42) located on the rod (32) of the piston arrives opposite the light (45) of the cylinder (35). At this time, the compression chamber (40) finds itself in communication with the casing (15) and the pressure drops.
• the flow rate is adjusted by rotation of the piston rod (32) inside the cylinder (35). This rotation is obtained by the action of the rack (56) on the half-ring (31) which causes the pivoting.
• an inclined ramp (47) is arranged at the head (41) of the piston rod (32). Depending on the angle of the piston (30) relative to the cylinder (35), and therefore to the light (45), the instant of facing of the ramp (47) and the light (45) will be variable . This allows the flow rate and the injection advance to be adjusted.
• this assembly makes it possible to have two pumps with a single drive, which reduces the mass and the cost of such an embodiment.
• a pump not using return springs for its injection function makes it possible to have rotation speeds significantly higher than all the pumps currently existing, with less noise, less heating and less dissipated power.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Fuel-Injection Apparatus (AREA)

Applications Claiming Priority (3)

Publications (2)

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ID=9468696

Family Applications (1)

Country Status (6)

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Family Cites Families (8)

• 1994
  • 1994-11-07 FR FR9413507A patent/FR2726606B1/fr not_active Expired - Fee Related
• 1995
  • 1995-11-06 WO PCT/FR1995/001452 patent/WO1996014496A1/fr active IP Right Grant
  • 1995-11-06 EP EP95939324A patent/EP0791129B1/de not_active Expired - Lifetime
  • 1995-11-06 DE DE69504531T patent/DE69504531D1/de not_active Expired - Lifetime
  • 1995-11-06 US US08/836,391 patent/US6109894A/en not_active Expired - Fee Related
  • 1995-11-06 CN CN95197272A patent/CN1171833A/zh active Pending

Non-Patent Citations (1)

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