Injector arrangement

State of the art

p0001The invention relates to an injector arrangement, in particular an injector block for fuel injection systems of mixture-compressing, externally-ignited internal combustion engines. The injector arrangement specifically relates to the allocation of natural gas for the internal combustion engine.

p0002For the supply of natural gas, in particular compressed natural gas (CNG), arrangements which are adapted to the respective motor vehicle are required in which, for example, suitable openings for the mounting of valves or fastening points for the holders of a fuel distributor bar are required on the corresponding suction module. Thus a vehicle-specific adjustment is necessary. Cost-effective retrofitting sets for gasoline-powered vehicles which retrofit them to CNG operation generally do not achieve the quality required specifically for emerging markets.

p0003From the <patcit id="pcit0001" dnum="WO2010049966A1"><text>WO 2010/049966 A1</text></patcit> A fuel distribution device is already known, in particular for gaseous fuels (LPG, methane). This fuel distribution device comprises a distributor block which has a gas inlet nozzle as well as several access openings to the fuel-emitting nozzles. The nozzle diffusers are controlled by control units directly on the manifold block. In addition, an electric heating device is provided on the longitudinal side of the distributor block, with which residual gas in the distributor block can be heated before starting the internal combustion engine.

p0004From the <patcit id="pcit0002" dnum="FR2935028A"><text>FR 2 935 028 A</text></patcit> A fuel distribution device is also already known, in which a plurality of fuel injection valves are supplied with liquid fuel. The fuel injection valves are connected to a distributor line via bent connecting sleeves. At connecting portions of the connecting sleeves, the fuel injectors and the manifold are indirectly connected to the cylinder head.

Disclosure of the invention

p0005The inventive injector arrangement with the features of claim 1 has the advantage that a compact design with a wide range of applications is possible. In particular, a compact and universal solution can be created for initial construction and retrofitting, which is cost-effective and at the same time of high quality.

p0006Advantageous refinements of the injector arrangement indicated in claim 1 are possible by the measures specified in the subclaims.

p0007The fuel distributor rail is preferably used for distributing natural gas to the injection valves. As a result, the injector arrangement is particularly suitable for natural gas in order to enable a mixture operation of a mixture-competing, externally-ignited internal combustion engine with gasoline and natural gas. The natural gas is here preferably stored as compressed natural gas in a gas storage tank, for example at pressures of about 20 MPa (200 bar). Such a compressed natural gas is also referred to as CNG. However, the concept of natural gas is not limited to natural gas, but is to be understood in general terms. For example, the natural gas can also be obtained artificially by means of coal gasification. Thus, the term natural gas also means natural gas-like fuels.

p0008It is advantageous that the connecting pieces each have a hose spout at their outlet sides. By means of suitable hose connections, a connection to a suction pipe of the internal combustion engine can thereby be effected. This allows great flexibility. In particular, adaptation to differently designed internal combustion engines is possible. The injector arrangement can thereby also be adapted to differently designed internal combustion engines, for example to a row arrangement as well as to a box arrangement of the cylinders of the internal combustion engine.

p0009It is also advantageous that the counter-holder with the connecting pieces is formed from a plastic-based plastic part. As a result, the connecting pieces can be designed together with the counter-holder, in particular as an integrated injection-molded part. However, it is also advantageous that the counter-holder and the connecting pieces are formed from at least one metallic material and that the connecting pieces are connected in a form-locking or force-locking manner to the counter-holder. For example, the counter-holder and the connecting pieces can be made of steel or aluminum. The connection of the connecting pieces with the counter-holder can be formed by screw, soldering or welding connections.

p0010In addition, it is advantageous that the injection valves are attached to the counter-holder by means of in each case at least one sealing ring, and that the sealing rings are designed as elastic sealing rings. Furthermore, it is advantageous that the injection valves are clamped between the opposing holder and the fuel distributor strip and / or are mounted in a floating manner with respect to the counter-holder. By means of the elastic sealing rings, it is possible here to achieve a floating mounting of the injection valves with respect to the counter-holder. For example, the sealing rings can each be formed from an elastomer. In this way, direct contact of the injection valves with the obturator is avoided so that a possible vibration transmission into the injection valves, which can cause increased wear, is prevented.

p0011In addition, it is advantageous that the counter-holder is connected to the fuel distributor strip by separate connecting elements. It is also possible that advantageously at least one connecting element is designed on the counter-holder and that the connecting element of the counter-holder is connected to the fuel distributor bar. As a result, the injector arrangement can be designed as a compact unit, in which the individual components are reliably connected to one another and positioned relative to each other. This also facilitates the assembly of the entire injector arrangement. In addition, retrofitting the injector arrangement to a gasoline-operated internal combustion engine is considerably simplified. In this case, it is also advantageous that valve bodies are provided on the fuel distributor rail, into each of which an injection valve is inserted. The injection valves can thereby be connected by connecting brackets to the associated valve bodies.

p0012It is also advantageous that the fuel distributor bar is at least essentially made of an aluminum-based bar profile. Furthermore, it is advantageous that the fuel distributor rail is at least essentially formed from a stainless steel part, in particular a soldered stainless steel part. This makes it possible to design a fuel distributor bar which is sufficiently stiff, withstands the pressure of the natural gas and can also be produced inexpensively.

p0013The configuration of the injector arrangement can have two or more injection valves, the counter holder comprising a corresponding number of connecting pieces. In this way, a suitable embodiment of the injector arrangement can be selected with respect to the respective application, in particular with regard to the number of cylinders of the internal combustion engine.

p0014Thus, a compact and universally applicable injector application can be designed. A robust and high-quality design is possible. This can, in particular, be significantly more robust and of higher quality than conventional retrofit sets. In this case, a simple mounting on a suction module or in the engine compartment can be made possible. It is also possible to achieve a standard that allows certification according to ECE R110 or a comparable standard.

BRIEF DESCRIPTION OF THE DRAWINGS FIG

p0015Preferred embodiments of the invention are explained in more detail in the following description with reference to the accompanying drawings, in which corresponding elements are provided with corresponding reference symbols. It shows:<ul><li><figref idrefs="f0001">FIG</figref> 4 shows an injector arrangement in a spatial exploded view according to a first exemplary embodiment of the invention;</li><li><figref idrefs="f0002">FIG</figref> 2 shows an injector arrangement in a spatial representation according to a second exemplary embodiment of the invention;</li><li><figref idrefs="f0003">FIG</figref> 4 shows an injector arrangement in a spatial representation according to a third exemplary embodiment of the invention, and FIG</li><li><figref idrefs="f0004">FIG</figref> 4 shows an injector arrangement in a spatial exploded view according to a fourth exemplary embodiment of the invention.</li></ul>

Embodiments of the Invention

p0016<figref idrefs="f0001">FIG</figref> Shows an injector arrangement 1 in a spatial explosion representation in accordance with a first exemplary embodiment. The injector arrangement 1 can, in particular, serve as an injector block 1 for fuel injection systems of mixture-compressing, externally-ignited internal combustion engines. The injector arrangement 1 has a fuel distributor strip 2, which can be formed from a metallic material, in particular aluminum. Specifically, the fuel distributor bar 2 can be formed from an extruded profile. A connecting piece 3 is mounted on the fuel distributor strip 2. Here, a sealing ring 4 is provided which is arranged between the connecting piece 3 and the fuel distributor strip 2. A fuel tank can, for example, be connected to the connecting piece 3 via a piping. The fuel tank can be used for storing natural gas, in particular compressed natural gas (CNG). Compressed natural gas is then fed into the fuel distributor rail 2 via the connecting piece 3. Furthermore, a sensor 5 is mounted on the fuel distributor rail 2, a connecting element connected to the sensor 5 enabling a connection to a control unit. The sensor 5 can, for example, be used for measuring the pressure and the temperature of the natural gas in the fuel distributor bar 2.

p0017The injector arrangement 1 also has a counter-holder 7, which comprises connecting pieces 8, 9, 10, Furthermore, connecting elements 12, 13, 14 are formed on the counter-support 7. The counter-holder 7 with the connecting pieces 8 to 11 and the connecting elements 12 to 14 is formed in one piece from a plastic-based plastic part in this exemplary embodiment. As a result, a cost-effective production of the entire counter-holder 7 with the connecting pieces 8 to 11 and the connecting elements 12 to 14 is possible.

p0018The connecting pieces 8 to 11 each have a hose spout 19, 20, 21, 22 at their outlet sides 15, 16, 17, 18. A hose can each be connected to the hose nozzles 19 to 22 in order to connect the injector arrangement 1, for example, with intake pipes for individual cylinders of the internal combustion engine.

p0019In this embodiment, the injector arrangement 1 has four injection valves 23, 24, 25, 26. The first injection valve 23 is joined to the counter-holder 7 at an inlet side 27 of the first connection piece 8. Correspondingly, the second injection valve 24 and the further injection valves 25, 26 are also joined to the counterpart 7 at the inlet sides 28, 29, 30 of the connecting pieces 9 to 11. In this case, elastic sealing rings 31, 32, 33, 34 are provided, by means of which the injection valves 23 to 26 are joined to the counterpart 7. In this case, the elastic sealing rings 31 to 34 surround the injection valves 23 to 26 at their injection-side end. The elastic seal rings 31 to 34 may be formed of an elastomer. A floating mounting of the injection valves 23 to 26 is ensured by the elastic sealing rings 31 to. Due to the floating bearing, a direct contact of the injection valves 23 to 26 with the counter-holder 7 is avoided so that a possible vibration transmission into the injection valves 23 to 26 is avoided. Such a possible vibration transmission can lead to increased wear which is thus avoided.

p0020The injector arrangement 1 also has fastening elements 35, 36, 37, which in this exemplary embodiment are designed as screws 35 to 37, in particular cylinder head screws 35 to 37. The screw 35 has a collar 38, which in the installed state engages behind the connecting element 12 at an opening 39. The screw 35 is screwed into the fuel distributor strip 3. Correspondingly, the screws 36, 37 have collars 40, 41, which engage the connecting elements 13, 14 at openings 42, 43. In this exemplary embodiment, the connecting elements 12 to 14 bear against the underside 44 of the fuel distributor strip 2 in the mounted state. In the assembled state, the injection valves 23 to 26 are thereby clamped between the counter-holder 7 and the fuel distributor strip 2 and are mounted in a floating manner with respect to the counter-holder 7. In addition, the injection valves 23 to 26 are each enclosed by an elastic sealing ring 45, 46, 47, 48 on their end facing the fuel distributor strip 2, which ensures a seal between the injection valves 23 to 26 and the fuel distributor bar. The sealing rings 45 to 48 can be formed from an elastomer.

p0021In the assembled state, a compact injector arrangement thus results. This compact design facilitates further assembly, which can be carried out during initial equipment as well as during retrofitting. This results in a wide range of applications since a flexible adaptation to the respective internal combustion engine is possible by means of hoses which can be connected to the hose nozzles 19 to 22. In addition, the basic design principle can also be maintained when the injector arrangement 1 is adapted to another cylinder number, and some components can be mounted unchanged with different cylinder numbers. An adaptation can be effected, for example, by an adaptation of the fuel distributor strip 2 and of the counter-holder 7.

p0022<figref idrefs="f0002">FIG</figref> Shows an injector arrangement 1 in a spatial representation according to a second exemplary embodiment. In this exemplary embodiment, the counter-holder 7 with the connecting pieces 8 to 11 is designed as a plastic part. The counter-holder 7 is connected to the fuel distributor strip 2 by separate connecting elements 12, The separate connecting elements 12, 13 are, on the one hand, suitably connected to the fuel distributor strip 2 and, on the other hand, in a suitable manner to the counter-holder 7. The configuration of the respective connections can, for example, be effected by means of fastening elements, in particular screws, in particular cylinder head screws, by soldering, welding or in another way.

p0023In this exemplary embodiment, the fuel distributor strip 2 is formed from a metal, in particular stainless steel. In this case, the fuel distributor strip 2 is preferably formed from a soldered stainless steel part 2.

p0024The underside 44 of the fuel distributor strip 2 faces the support 7. The connector 3 and the sensor 5 with the connection element 6 are mounted on an upper side 50, which is remote from the underside 44 and is designed in a flat manner. The position of the connecting piece 3 and of the sensor 5 with the connecting element 6 on the upper side 50 can, if appropriate, also take place differently.

p0025In this exemplary embodiment, valve bodies 51, 52, 53, 54 are provided on the fuel distributor rail 2, into which in each case one of the injection valves 23 to 26 is inserted with its upstream end. The injection valves 23 to 26 are reliably clamped between the counter-holder 7 and the fuel distributor strip 2 by the connection of the counter-holder 7 with the fuel distributor strip 2.

p0026<figref idrefs="f0003">FIG</figref> Shows an injector arrangement 1 in a spatial representation according to a third exemplary embodiment. In this exemplary embodiment, fastening bolts 55, 56 are attached to the holder 7, on which the fastening elements 12, 13 can be fastened. In this case, the fastening bolts 55, 56 can also be encapsulated by the plastic material of the counter-holder 7. This forms a form-fitting connection between the connecting pins 55, 56 and the counter-holder 7. Furthermore, it is possible that the fastening bolt 55 is integrally formed with the connecting element 12. Correspondingly, the fastening bolt 56 can also be integrally formed with the connecting element 13. The connecting elements 12, 13 have bores 12 ', 13' which enable the injector arrangement 1 to be secured in the engine compartment of a vehicle or the like.

p0027In addition, in this exemplary embodiment, connecting clips 57, 58, 59, 60 are provided which connect the injection valves 23 to 26 with the valve seats 51 to 54. In this way, the injection valves 23 to 26 are held on the fuel distributor bar 2.

p0028<figref idrefs="f0004">FIG</figref> Shows an injector arrangement 1 in a spatial explosion representation according to a fourth exemplary embodiment. In this exemplary embodiment, the connecting elements 12, 13, which connect the opposing element 7 to the fuel distributor strip 2, are designed as spacer sleeves 12, 13. In this case, the connecting elements 12, 13 are screwed or soldered to the fuel distributor strip 2. In addition, the counter-holder 7 is made of a metallic material. The connecting elements 12, 13 are screwed or soldered to the counter-holder 7. The counter-holder 7 can be formed, for example, from steel or aluminum. In this case, the counter-holder 7 can be formed from a square, a round material or the like. The connecting pieces 8 to 11 with the hose sleeves 19 to 22 are formed in this exemplary embodiment from a metallic material. In this case, the connecting pieces 8 to 11 are connected to the counter-holder 7 by a screwed, soldered or welded connection. Thus, the connecting pieces 8 to 11 are positively or non-positively connected to the counterpart 7.

p0029The invention is not limited to the described embodiments but to the subject matter of the appended claims.