COMPONENT FOR AN INJECTION SYSTEM AND INJECTION SYSTEM FOR SPARK-IGNITION INTERNAL COMBUSTION ENGINES THAT COMPRESS THE MIXTURE, AS WELL AS A METHOD FOR PRODUCING THIS COMPONENT

Abstract

Component (3; 3') for an injection system (1) for spark-ignition internal combustion engines used to meter a high-pressure fluid, in particular a high-pressure line (5) or a fluid distributor (2), comprising a base body (14; 13) in which at least one hydraulic connection (15-20) is provided, wherein at least the base body (14; 13) with the connection (15-20) is formed by single- or multi-stage forging, wherein an interior space (11) is formed in the base body (14; 13) by chip-removal machining after forging, and wherein a connection channel (26-31) is formed in the connection (15-20) which intersects in an intersection region (40-45) with the interior space (11) by chip-removal machining after forging. It is proposed that the intersection region (40 - 45) be deburred by mechanical deburring.The invention also relates to an injection system (1) and a method for producing this component (3; 3').

Description

COMPONENT FOR AN INJECTION SYSTEM AND INJECTION SYSTEM FOR SPARK-IGNITION INTERNAL COMBUSTION ENGINES THAT COMPRESS THE MIXTURE, AS WELL AS A METHOD FOR PRODUCING THIS COMPONENT BACKGROUND OF THE INVENTION The invention relates to a component, in particular a fuel line or fuel distributor, for an injection system used in spark-ignition internal combustion engines that compress the fuel-air mixture. Specifically, the invention relates to the field of motor vehicle injection systems in which direct fuel injection is performed into the combustion chambers of an internal combustion engine. A method for producing a fuel distributor is known from patent DE 10 2016 115 550 A1, in which a distributor tube is produced from a forged preform. Austenitic steels with material numbers 1.4301, 1.4306, 1.4307, and 1.4404 can be used in this case. It has been recognized that the forged preforms have residual stresses from the forging process due to production, and that corrosion resistance is reduced due to the resulting chromium carbides. In the known method, the chromium carbides generated by slow cooling are dissolved by controlled heat treatment between 850 °C and 1100 °C for more than 60 seconds. This improves the mechanical properties and corrosion resistance. Since heat treatment also improves machinability properties for drilling, milling, and tapping, heat treatment is preferably carried out on the unmachined forging preform. BRIEF DESCRIPTION OF THE INVENTION The component according to the invention with the features of claim 1 and the injection system according to the invention with the features of claim 8, as well as the method according to the invention according to claim 9, with the features of claim 1, have the advantage that an improved configuration and mode of operation are made possible. The advantageous developments of the component specified in claim 1, the injection system specified in claim 8, and the method specified in claim 9 are made possible by the measures specified in the dependent claims. The injection system according to the invention is for spark-ignition internal combustion engines that compress the mixture. The injection system according to the invention is for injecting gasoline and / or ethanol and / or comparable fuels and / or for injecting a mixture of gasoline and / or ethanol and / or comparable fuels. A mixture may be, for example, a mixture with water. The component according to the invention is for these injection systems. At least the base body of the component is made from a material, preferably stainless steel, particularly austenitic stainless steel. Specifically, the material may be based on austenitic stainless steel with material number 1.4301 or 1.4307 or a comparable stainless steel. A hydraulic connection provided in the base body may be configured as a high-pressure inlet, high-pressure outlet, or other high-pressure connection. Preferably, the base body is further formed and machined, along with the high-pressure inlet and at least one high-pressure outlet, and, if appropriate, one or more other high-pressure connections, during production as a forged preform. In a proposed fuel distributor configuration, significant differences arise compared to a weld-on rail, where a tube for the weld-on rail is machined and deburred before the mounting components are welded. The forged configuration allows for sizing for higher pressures. A significant difference compared to a high-pressure rail for compression-ignition internal combustion engines is the material selection and machining, particularly the forging of stainless steel. Significant differences also arise compared to electrochemical deburring (ECM deburring). ECM deburring requires a separate system and a subsequent cleaning process, which represents a negligible portion of production costs.Conversely, the proposed mechanical deburring can be easily carried out after a machining process and, in particular, can be performed in the same machining center. This applies especially to a proposed pull-out deburring process according to the advantageous improvement of claim 2, since one or more pull-out deburring machines can be advantageously integrated into the machining process. Therefore, production can be simplified and unit costs reduced. Another advantage of the proposed mechanical deburring over ECM deburring arises with respect to the material state. In ECM deburring, excess material or at least a burr is electrochemically dissolved at a hole intersection, resulting in a material state virtually free of residual pressure stress. In contrast, a proposed configuration can achieve a material state with residual pressure stress, which has higher cyclic strengths, particularly under pulsating internal pressure loads. This is especially relevant in the case of an advantageous application according to claim 3. Therefore, an additional process that increases strength, such as self-banding, can be advantageously avoided. The further advantageous developments according to claim 4 and / or claim 5 are particularly beneficial in this case. An advantageous geometric configuration is possible in accordance with the advantageous development according to claim 6. In particular, in this way advantageous deburring is possible with a rotating deburring tool, in particular a pull-out deburring machine. An advantageous configuration of the base body with the hydraulic connection or connections is possible according to claim 7. In this case, reliable process control is possible through mechanical deburring. In the case of ECM deburring, for example, when power is supplied to an electrode through contact between the electrode and a burr to be removed, a short circuit could occur if the burr to be removed is too large, thus stopping the process without material erosion. This problem arises particularly with the proposed austenitic stainless steels, as they are comparatively difficult to machine. In particular, forging can introduce undesirable structural components such as delta ferrite and martensite formation. Reliable process control can be achieved in this case as well using the proposed mechanical deburring method. ECM deburring, on the other hand, could result in uneven erosion, since the dissolution behavior depends on the microstructure. These disadvantages are avoided by the proposed mechanical deburring method, even in an advantageous configuration according to claim 7. The corresponding advantages in an advantageous development of the method in accordance with claim 10 and / or claim 11. BRIEF DESCRIPTION OF THE FIGURES The preferred exemplary embodiments of the invention are explained in more detail in the following description with reference to the accompanying figures, in which the corresponding elements are provided with their respective reference symbols. It is shown: Figure 1 is an injection system for a spark-ignition internal combustion engine that compresses the mixture with a component configured as a fuel distributor in a schematic cross-sectional representation in accordance with an exemplary embodiment of the invention; Figure 2 shows the component section identified in Figure 1 with II in accordance with the example modality in a detailed schematic representation; Figure 3 shows the component section identified in Figure 1 with III in accordance with the example modality in a detailed schematic representation in a section perpendicular to a longitudinal axis of the component and iviA / a / zuzz / u ι iz / 1 Figure 4 shows a schematic representation of a mechanical deburring of an intersection region to explain a possible configuration of the invention. DETAILED DESCRIPTION OF THE INVENTION Figure 1 shows an injection system 1 with a fuel distributor (fluid distributor) 2 in a schematic cross-sectional representation according to an exemplary embodiment. In this exemplary embodiment, the fuel distributor 2 of the fuel injection system 1 is a component 3 configured according to the invention. A high-pressure pump 4 is also provided. The high-pressure pump 4 is connected to the fuel distributor 2 via a fuel line 5 configured as a high-pressure line 5. During operation, a fuel or a fuel mixture is supplied as a fluid at an inlet 6 of the high-pressure pump 4. In this case, the high-pressure line 5 can also be configured accordingly as a component 3' according to the invention. The fuel distributor 2 serves to store and distribute fluid to injection valves 7 to 10 configured as fuel injection valves 7 to 10 and reduces pressure fluctuations and pulsations. The fuel distributor 2 can also serve to dampen pressure pulsations that may occur during the switching of fuel injection valves 7 to 10. In this case, high pressures p may occur at least temporarily during operation in an internal space 11 of component 3. The high-pressure line 5 has hydraulic connections 12, 12' configured as a high-pressure inlet 12 and a high-pressure outlet 12', which may be interchangeable, as well as a base body 13. The fuel distributor 2 has a tubular base body 14, which is formed by single- or multi-stage forging. A hydraulic connection 15, configured as a high-pressure inlet 15, and several hydraulic connections 16 to 19, configured as high-pressure outlets 16 to 19 or cups 16 to 19, are provided on the tubular base body 14. Additionally, a hydraulic connection 20, configured as a pressure sensor connection 20, is provided on the tubular base body 14. In this example embodiment, the tubular base body 14, the high-pressure inlet 15, the high-pressure outlets 16 to 19, and the pressure sensor connection 20 are formed from a single forged part 14'. Therefore, the high-pressure inlet 15, the high-pressure outlets 16 to 19, and the pressure sensor connection 20 are forged into the base body 14. Fuel line 5 connects at its high-pressure inlet 12 to the high-pressure pump 4 and at its high-pressure outlet 12' to the high-pressure inlet 15 of fuel distributor 2. Fuel injection valves 7 to 10 are connected respectively to the high-pressure outlets 16 to 19 of fuel distributor 2. In addition, MA / a / ZUZZ / UI 1Z / 1 a pressure sensor 21, which connects to the pressure sensor connection 20. At one end 22, the tubular base body 14 is closed by a locking screw 23. In a modified configuration, an axial high pressure inlet can be provided at one end 24 instead of the lateral and / or radial high pressure inlet 15. After forging, the tubular base body 14 or the forged individual part 14' is machined by at least one chip removal process. In this example, the tubular base body 14 is configured after forging with a hole 25 to create the internal space 11. During operation, the fluid supplied at the high-pressure inlet 15 can be distributed through the internal space 11 to the fuel injection valves 7 to 10 connected to the high-pressure outlets 16 to 19. Furthermore, holes 26 to 31 are machined into the forged individual part 14'. In this case, holes 27 to 30 serve for the high-pressure outlets 16 to 19. Hole 26 serves for the high-pressure inlet 15. Hole 31 serves for the connection of pressure sensor 20. Additionally, a thread 22' can be cut into hole 25 at the end 22 of the base body 13. Furthermore, perforations 32 to 37 can be provided in the high-pressure inlet 15, the high-pressure outlets 16 to 19, and the pressure sensor connection 20, forming connection spaces 32 to 37. In this example embodiment, hole 25 is axially oriented with respect to a longitudinal axis 38. Holes 26 to 37 are oriented radially or eccentrically with respect to the longitudinal axis 38. In the case of a radial or radially eccentric orientation with respect to the longitudinal axis 38, for example, when mounting in an engine compartment, then the holes 26, 31, 32, and 37 of the connections 15 and 20, or the holes 27 to 30 and 33 to 36 of the connections 16 to 19, can preferably be oriented above or below the longitudinal axis and / or away from the longitudinal axis 38, pointing away from, or that points towards an engine. Through holes 26 to 31, connecting channels 26 to 31 are formed, intersecting with the interior space 11. These connecting channels 26 to 31 connect holes 32 to 37 with the interior space 11. In this case, holes 26 to 31 intersect with hole 25, which forms the interior space 11. In this case, intersection regions 40 to 45 are obtained, in which burrs remain after machining by chip removal. Intersection regions 40 to 45 are deburred by mechanical deburring. A possible configuration of connections 15, 20 is described by way of example based on connection 15 with the aid of Figure 2. A possible configuration of connections 16 to 19 is described by way of example with respect to connection 16 with the aid of Figure 3. A possible configuration for mechanical deburring is described with the aid of Figure 4. In this way, a possible configuration of a component 3 iviA / a / zuzz / u ι iz / 1 is configured in accordance with an example embodiment of the invention. Correspondingly, another component 3' of the injection system 1, for example, the high-pressure line 5, can also be implemented, wherein connections 12, 12' can be configured accordingly and mechanically deburred. Figure 2 shows the section of component 3, identified as II in Figure 1, in accordance with the example embodiment, in a detailed schematic representation. A tapered and / or stepped transition 46 is provided between holes 26 and 32 in this example embodiment. Specifically, holes 26 and 32 can be arranged coaxially in this case. Depending on the application, a suitable thread can also be formed at connection 15, for example, to connect the high-pressure line 5. Deburring of the intersection region 40 can be done from hole 32, as also explained with the help of figure 4. In the intersection region 40, a chamfer 40' can be configured in this way. Figure 3 shows the section of component 3, identified in Figure 1 as III, according to the example embodiment, in a detailed schematic representation in a section perpendicular to the longitudinal axis 38. In this example embodiment, hole 33 has a flat hole base 47, wherein hole 33 is arranged eccentrically with respect to hole 27. Hole 27 can be oriented radially with respect to the longitudinal axis 38. Hole 33 is then oriented eccentrically radially with respect to the longitudinal axis 38. Deburring of the intersection region 41 can be performed from hole 33, as illustrated with the aid of Figure 4. A chamfer 4Γ can thus be configured in the intersection region 41. Therefore, connection 15 in this example mode can be made in the form of a valve cup 15. Figures 2 and 3 illustrate possibilities for creating non-eccentric and eccentric connection geometries, in which mechanical deburring can be performed. Figure 4 shows a schematic representation of the mechanical deburring of an intersection line 40 by means of a withdrawal deburring tool 50 to illustrate a possible embodiment of the invention. Holes 25 and 26 intersect each other in the intersection region 40. The withdrawal deburring tool 50 can be supplied through hole 32 (Figure 2) along an axis 51. The withdrawal deburring tool 50 has at least one blade 52. During supply, the blade 52 folds completely or partially onto a coating surface 53 of the withdrawal deburring tool 50. The deployment of the blade 52 can be effected by rotation 54 and / or by an inlet with a coolant lubricant supplied through the withdrawal deburring tool 50. By withdrawing the withdrawal deburring tool 50 in a withdrawal direction 55, mechanical deburring of the intersection region 40 is achieved by means of the blade 52 due to rotation 54. Through rotation 54 and / or via the supplied liquid coolant lubricant, the blade 52 is applied against the intersection region 40. In this case, the chamfer 40' can be formed. Subsequently, the withdrawal deburring tool 50 can be removed, whereby the blade 52 is again folded completely or partially against the coating surface 53. Therefore, mechanical burr removal and chip removal of edges can be achieved in the intersection region 40. Depending on the configuration of the withdrawal deburring tool 50, the blade 52 can also be retained, for example, by a spring, to facilitate the insertion and removal of the withdrawal deburring tool 50. The temporary chip-removal machining procedure for setting holes 25 to 37 can be performed appropriately. In this case, the mechanical deburring of the intersection regions 40 to 45 can be properly integrated into this machining or connected to it. In the case of a possible implementation of the method, hole 25 can first be drilled for the configuration of the inner space 11. Next, holes 32 to 37 can be drilled for the connection geometries of connections 15 to 20, and holes 26 to 31 can be drilled as connection channels 26 to 31 towards the inner space 11. Mechanical deburring of the intersection regions 40 to 45 can then be performed. Therefore, mechanical deburring can be linked to machining by chip removal. In one possible embodiment of the method, all connection geometries are machined after drilling hole 25 for the inner space 11, in particular all holes 32 to 37 are drilled, then all holes 26 to 31 that serve as connection channels 26 to 31 or as connection holes 26 to 31 are drilled and finally all intersection regions 40 to 45 are mechanically deburred. A possible variation of this method involves a different sequence during drilling and deburring, integrating deburring into the machining process. If several intersection regions 40 to 45 are mechanically deburred, then a machining sequence can be applied to each of the connections 15 to 20. This means, for example, that in connection 15, hole 32 is drilled, then hole 26 is drilled, and then mechanical deburring of intersection region 40 is performed. These steps can be repeated sequentially for each of the connections 15 to 20. Therefore, mechanical deburring is not necessarily performed after the completion of machining. In particular, mechanical deburring can be integrated into machining. By using appropriate process parameters and selecting a suitable coolant, it is also possible to configure an inner wall 60, extending, among other things, from hole 25 through the intersection region 40 and through hole 26, with a material state containing residual pressure stress. This inner wall 60 can also extend to the transition 46 (Figure 2) or to the base of hole 47 (Figure 3) and at least partially through holes 32 to 37. Configuring the inner wall 60 with the material state containing residual pressure stress results in improved cyclic strength. The invention is not limited to the example modalities described. NOVELTY OF THE INVENTION Having described the present invention, it is considered a novelty and, therefore, the contents of the following are claimed as property.

Claims

1. A component (3; 3') for an injection system (1) for spark-ignition internal combustion engines used to meter a high-pressure fluid, in particular a high-pressure line (5) or a fluid distributor (2), comprising a base body (14) in which at least one hydraulic connection (15-20) is provided, wherein at least the base body (14) with the connection (15-20) is formed by single- or multi-stage forging, wherein an interior space (11) is formed in the base body (14) by machining after forging, and wherein a connecting channel (26-31) is formed in the connection (15-20) intersecting the interior space (11) in an intersection region (40-45) by machining after forging, characterized in that the intersection region (40-45) is deburred. mechanic.

2. Component according to claim 1, characterized in that the intersection region (40 - 45) is deburred by a mechanical deburring removal.

3. Component according to claim 2, characterized in that a forged material of the base body (13) in an inner wall (60) of the base body (13), which during operation is pressurized by the high pressure (p) of the fluid, is configured with a material state with residual pressure stress.

4. Component according to any of claims 1 and 3, characterized in that the inner wall (60) of the base body (13), configured in the material state with residual pressure stress, delimits the inner space (11) and / or that the inner wall (60) of the base body (13), configured in the material state with residual pressure stress, extends over the intersection region (40 - 45) and / or that the inner wall (60) of the base body (13), configured in the material state with residual pressure stress, extends at least through the connection channel (26 - 31) of the hydraulic connection (15 - 20).

5. Component according to claim 4, characterized in that the hydraulic connection (15 - 20) has a connection space (32 - 37), which is joined to the inner space (11) through the connection channel (26 - 31), and that the inner wall (60), configured with the material state with residual pressure stress, extends from the connection channel (26 - 31) at least partially over the connection space (32 - 37) of the connection (15 - 20).

6. Component according to any of claims 1 and 5, characterized in that the interior space (11) of the base body (13) is configured by at least one hole (25) and / or that the connection channel (26 - 31) is configured by at least one hole (26 - 31).

7. Component according to any of claims 1 and 6, characterized in that the base body (13) and the at least one hydraulic connection (15 - 20) are formed from a single forged part (14') and / or that the base body (13) is formed from a material that is based on an austenitic stainless steel, in particular an austenitic stainless steel with material number 1.4301 or 1.4307 or a stainless steel comparable thereto.

8. Injection system (1) for spark-ignition internal combustion engines for injecting a fuel fluid, in particular gasoline and / or ethanol, and / or a fuel mixture, with at least one component (3, 3') according to one of claims 1 to 7.

9. Method for producing a component (3; 3') for an injection system for a spark-ignition internal combustion engine used to meter a high-pressure fluid, fuel, in particular gasoline and / or ethanol, and / or a mixture with fuel, in particular a method for producing a high-pressure line (5) or a fluid distributor (2), wherein a base body (14; 13), and at least one hydraulic connection (15 - 20) provided in the base body (13) are formed by a single- or multi-stage forging, wherein in the base body (14;13) an interior space (11) is formed by machining after forging, and in which a connecting channel (26-31) is formed intersecting with the interior space (11) at the connection (15-20) by machining after forging, fixed in an intersection region (40-45), characterized in that the intersection region (40-45) is deburred by mechanical deburring.

10. Method according to claim 9, characterized in that a blade (52) of a withdrawal deburring tool (50) serving for mechanical deburring is pressurized against the intersection region (40 - 45) by a liquid coolant lubricant supplied for mechanical deburring and / or a blade (52) serving for mechanical deburring of a withdrawal deburring tool (50) is pressurized for deburring by rotating the withdrawal deburring tool (50) against the intersection region (40 - 45).

11. Method according to claim 9 or 10, characterized in that a liquid cooling lubricant supplied for cooling during mechanical deburring is established at least temporarily at such a high pressure that a forged material of the base body (13) in an inner wall (60) of the base body (13), which during the operation is pressurized by the high fluid pressure, is configured with a material state with residual pressure stress.

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