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
  • F02M55/00—Fuel-injection apparatus characterised by their fuel conduits or their venting means; Arrangements of conduits between fuel tank and pump F02M37/00
  • F02M55/02—Conduits between injection pumps and injectors, e.g. conduits between pump and common-rail or conduits between common-rail and injectors
  • F02M55/025—Common rails

Definitions

• the invention relates to a fuel distribution device for supplying the cylinders of an internal combustion engine, in particular a direct injection engine and more particularly an engine powered under relatively high pressure.
• the invention particularly relates to a new embodiment of such a device, easy to manufacture, easy to install and low cost.
• the fuel distributor in an internal combustion engine, with direct injection, comprises an elongated body, of generally tubular shape, connected by an axial end to the outlet of a fuel pump and comprising, arranged along its length, several output sockets made with protruding bosses. These output sockets are connected to the different injectors. Other sockets are possibly provided to be connected to pressure and / or temperature sensors, to a damper or to a regulator.
• the elongated tubular body is difficult to produce. A heavy monobloc part must be produced, which must in any case be resumed in machining.
• Such an elongated tubular body also comprises several supports or inking lugs for its attachment to the cylinder head.
• European patent application No. 0 427 977 describes a dispenser comprising an elongated cavity and of short length mounted on a base comprising a pressure and / or temperature sensor.
• the accesses to the cavity comprising in particular the inlet connected to the pump and the outlets connected to the injectors, are grouped on one end of the body. These accesses communicate with the cavity by holes. Most of these holes are made at an angle and lead to the upper part of the cavity.
• Such a dispenser is delicate and expensive to produce.
• the thickness of the walls of the body is relatively large and the part is heavy.
• the invention proposes a new type of fuel distribution device, easy to produce in large series with relatively low cost prices.
• One of the aims of the invention is to provide a distributor of reduced bulk and weight which is particularly resistant to high pressures.
• Another object of the invention is to provide such a distributor which can have a large number of accesses, for connections to the different cylinders and sensors of the engine, which can be arranged in numerous locations of said body.
• the invention relates to a fuel distribution device for supplying the cylinders of an internal combustion engine, of the type comprising a hollow body in the wall of which are provided accesses intended to be connected, in particular, a pressurized fuel supply source and a plurality of injectors for supplying said cylinders, characterized in that said hollow body comprises a part of an at least approximately spherical or oblong profile cavity and a stepped bore s' extending substantially radially between said portion of cavity and an orifice of said body, said bore comprising, separated by a shoulder, a first section, interior, communicating with said portion of cavity, and a second section, exterior, threaded, and in that an arrangement for plugging said bore comprises an internal part engaged in said first section, constituting a part of the inte face re of said cavity and a threade
• the cavity can be spherical, substantially spherical or with a slightly oblong profile.
• Said inner part of the closure arrangement may include a recess complementing said cavity.
• a seal can be interposed between the closure arrangement and said bore.
• the spherical or practically spherical shape of the cavity is advantageous insofar as all the access points can communicate with the cavity by means of bores, the internal terminal parts of which, at least, extend substantially radially. This makes it possible to arrange the accesses to any locations of the body all around the spherical or practically spherical cavity. Above all, the screw connection between the hollow body and the closure arrangement makes it possible to very significantly reduce the manufacturing costs for a surprisingly high pressure withstand.
• the inner part of the closure arrangement is separated from the threaded part.
• This inner part may include a first shoulder cooperating with that of the bore and, in this case, the seal, mounted between said body and said inner part, is not likely to be damaged when screwing said threaded part.
• This shoulder will be referred to hereinafter as "first shoulder"
• the seal can be housed in an annular groove formed on a cylindrical portion of said inner part. This seal can also be compressed between two shoulders including that of said bore.
• the shoulder of the bore can be chamfered so as to create an annular space capable of accommodating a seal of suitable shape.
• the shoulder of said stepped hole can be chamfered to define an enlarged annular space with said first shoulder of said inner part.
• said relatively flat seal has an annular allowance in the vicinity of its inner edge, adapted to occupy the enlarged annular space.
• the inner part of the closure arrangement and the threaded part may form a single piece.
• the volume of the cavity can be relatively reduced taking into account the displacement of the motor to be supplied.
• the volume of the cavity can be reduced to 30 cm 3 .
• FIG. 1 is an exploded perspective view of a fuel distribution device according to the invention
• - Figure 2 is a view of the same device, assembled, shown in a diametrical section of the cavity;
• - Figure 3 is a detail view on a larger scale, of the box III of Figure 2;
• FIG. 4 is a detail view, similar to Figure 3, illustrating a variant of the seal of the device of Figures 1 and 2;
• FIG. 5 is a view similar to Figure 2 illustrating a variant;
• - Figure 6 is a detail view on a larger scale of the box VI of Figure 5;
• Figure 7 is a view similar to Figure 6 illustrating a variant
• FIG. 8 is a view similar to Figure 5 illustrating another variant;
• - Figure 9 is a detail view on a larger scale of the box IX of Figure 8;
• FIG. 10 is a view similar to Figure 5 illustrating another variant
• FIG. 1 1 is a detail view on a larger scale of the box XI of Figure 10;
• - Figure 12 illustrates another variant allowing mounting directly on the pump; and - Figure 13 is a sectional view of a variant of the device according to the invention.
• a fuel distribution device 1 1 for the supply of the cylinders of an internal combustion engine, for example a diesel or petrol engine, with direct controlled injection, under relatively high pressure.
• the fuel is delivered to the device under high pressure by a pump and is distributed to injectors controlled by solenoid valves.
• the pressures involved are of the order of 100 to 150 bars for a petrol engine and from 1400 to 2000 bars for a motor.
• the distribution device essentially comprises a hollow body 12 in the wall of which are provided access points 14 intended to be connected, in particular, to a source of supply of pressurized fuel (the pump) and to a plurality of injectors supplying respectively the engine cylinders.
• the different accesses are not differentiated. They are formed on a solid crown 16 in one piece with said hollow body, possibly from molding, forging or other technique.
• control means such as for example a regulator and / or a damper and / or a pressure tap.
• the hollow body has a part 18 of a cavity
• each access 14 includes a hole 19 of small internal cross section with a substantially radial orientation and a tapped hole 20 of larger diameter emerging on the outside, here on the crown 16 and connecting to the small section hole.
• each small section hole 19 extends perpendicularly to the outer surface 16a of the crown, that is to say radially relative to the cavity 17 when the latter is spherical.
• the hollow body also includes a stepped hole 22 extending substantially radially between said cavity part 16 and an orifice 24 of the hollow body.
• This bore comprises, separated by a shoulder 26, a first inner section 28, communicating with said cavity part 17 defined in said body and a second, outer section 29, threaded.
• the device is completed by a plugging arrangement 30 of this stepped bore 22.
• This plugging arrangement consists of an inner part 32 engaged in said first section and one end face of which has a recess 34 completing said cavity, it that is to say, connecting with the cavity part 16 defined in said body and with a threaded part 36 screwed into said second section 29. At least one seal 40 is interposed between said plugging arrangement 30 and the bore 22.
• said inner part and said threaded part of the plugging arrangement 30 form a single piece.
• the seal 40 is here an at least relatively flat seal, interposed between the shoulder 26 of the bore and a shoulder 42 of this part, here defined between said inner part 32 and said threaded part 36.
• This shoulder 42 will be called “first shoulder” .
• the internal edge of the shoulder of said stepped bore 22 made in the body is chamfered (chamfer 45) to define an enlarged annular space with the single part composed of said inner part 32 and said threaded part 36.
• the seal at least relatively flat, however has an annular allowance in the vicinity of its inner edge, which is adapted to occupy this enlarged annular space.
• the internal part 32 is separated from the threaded part 36.
• the flat or relatively flat seals described above can be used with the embodiments of Figures 5 to 9, while all the other seals which will be described later can also be used with the embodiment of Figures 1 to 3. If we consider more particularly Figures 5 and 6, we see that the inner part 32 has a first shoulder 42 cooperating with that of the bore (shoulder 26).
• An O-ring 48 is iced in an annular groove 49 formed on a cylindrical portion of said inner part.
• a similar annular groove 49a can also house an anti-extrusion ring 50, adjoining said seal 48.
• said first section of the shouldered bore (that is to say the non-tapped section) has another shoulder 52 cooperating with a second shoulder 54 of said inner part 32. At least one seal 48 is clamped between said first shoulder 42 and said other shoulder 52.
• an anti-extrusion ring 50 is attached to the seal 48 and the assembly is clamped between these two shoulders.
• the internal part 32 is further separated from the threaded part 36 and the internal edge of the shoulder of the shouldered bore is chamfered (chamfer 45a) to define an enlarged space, here frustoconical, with said inner part 32, in particular its shoulder 42 (previously called the first shoulder) and a seal 56 with a suitable shape (annular seal with triangular section) to occupy this frustoconical annular space.
• the external face of the second section has an imprint 58 adapted to receive a screwing tool.
• the volume of the cavity could be much less than what is usually practiced and which is moreover necessary due to the elongated tubular shape of conventional intake devices.
• the reduced volume of the cavity (favorable to good sealing of the closure arrangement) could be reduced well below the usual values without disturbing the distribution.
• Figure 12 illustrates an important application in practice.
• the closure arrangement 30 (at least the threaded part 36) is combined with the outlet 59 of the injection pump 60.
• the threaded part 36 comprises a base 62 forming a flange and provided on its underside with a groove 63 housing a seal 64.
• the fuel injection is therefore carried out radially by a conduit 61 of very small diameter extending the outlet 59.
• the base 62 is fixed to the end of the pump by screws 65.
• the threaded part 36 could be formed all around the outlet 59 of the pump itself and the hollow body 12 would be directly screwed onto the pump, with interposition of the seal 40.
• the end of the outlet 59 of the pump would be shaped so as to present the recess 34. It would therefore be adapted to form a part (the closure arrangement) of the dispenser. This constitutes another important advantage of the screwed mounting of the elements of the dispenser.
• all the embodiments described above can be mounted at the pump outlet.
• Figure 13 illustrates another embodiment in which the cavity 17a has a slightly different shape. Instead of a sphere, the shape is approximately ovoid or slightly oblong in profile; it nevertheless has an axis of symmetry yy which is also that of said stepped hole 22a.
• the part of the cavity defined in the hollow body 12a comprises a substantially spherical end part 70, extended by a cylindrical portion 71 (for example of the order of 12 to 20 mm long ) into which the accesses 14a open.
• This cylindrical portion is itself extended by a neck 72 whose section decreases progressively towards the outside.
• This neck is extended by said shouldered bore, the inner section of which comprises a cylindrical portion 73 then, a frustoconical bearing 74 widening towards the shoulder.
• the frustoconical bearing 74 ends in the plane of the shoulder 26a.
• the closure arrangement 30a has two separate parts.
• the cavity is closed by an inner part 32a engaged in the first section; it constitutes part of the internal face of the cavity 17a.
• This inner part is held in place by a threaded part 36a screwed into said second section 29a, threaded for this purpose.
• the inner part of the closure arrangement has the general shape of a relatively thick pellet provided with a frustoconical peripheral portion 79 which comes to bear against the frustoconical bearing 74 defined above.
• the threaded part includes a recess in which the internal part 32a is embedded, which forms a sort of shutter with a conical bearing.
• the seal is ensured by the tight contact of the frustoconical surfaces 74 and 79.
• an additional seal relatively compressible can be interposed between the shoulder 26a formed in the body 12a and the end face of the threaded part 36a.
• the ports 14a are here respectively defined in massive extensions of the said body, which extensions form connection end pieces 80.
• Each port has a hole of small section 19a emerging in a substantially equatorial plane of the cavity (perpendicular to the yy axis). It opens to the outside via a conical mouthpiece 81 and the endpiece 80 has an external thread 84 at its end portion.
• one of the end pieces is shown equipped with a pressure sensor 82. External threading may prove to be advantageous.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Fuel-Injection Apparatus (AREA)
• Closures For Containers (AREA)
• Output Control And Ontrol Of Special Type Engine (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=9526496

Family Applications (1)

Country Status (10)

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Family Cites Families (4)

• 1998
  • 1998-05-19 FR FR9806306A patent/FR2778950B1/fr not_active Expired - Fee Related
• 1999
  • 1999-05-18 ES ES99919346T patent/ES2226381T3/es not_active Expired - Lifetime
  • 1999-05-18 WO PCT/FR1999/001180 patent/WO1999060263A1/fr not_active Ceased
  • 1999-05-18 AT AT99919346T patent/ATE272171T1/de not_active IP Right Cessation
  • 1999-05-18 DE DE69918926T patent/DE69918926T2/de not_active Expired - Lifetime
  • 1999-05-18 JP JP2000549849A patent/JP2002515563A/ja active Pending
  • 1999-05-18 PT PT99919346T patent/PT998631E/pt unknown
  • 1999-05-18 EP EP99919346A patent/EP0998631B1/de not_active Expired - Lifetime
  • 1999-05-18 CA CA002296757A patent/CA2296757C/fr not_active Expired - Fee Related
  • 1999-05-18 US US09/462,885 patent/US6196192B1/en not_active Expired - Lifetime

Non-Patent Citations (1)

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