EP2657504B1 - Holder system for fixing a component to a combustion engine - Google Patents

Description

State of the art

The invention relates to a holder for fastening at least one component, in particular a fuel distributor, to an internal combustion engine. Specifically, the invention relates to the field of fuel injection systems of internal combustion engines.

From the US 7,793,639 B2 a device is known which serves for noise reduction in an internal combustion engine with respect to vibrations of a fuel distributor. The device has a retaining clip which serves to fasten the fuel distributor to a cylinder head.

Disclosure of the invention

The holding system according to the invention with the features of claim 1 and the fuel injection system according to the invention with the features of claim 6 have the advantage that an improved vibration damping over the life is guaranteed. Specifically, there is the advantage that an effective noise attenuation over the life is guaranteed.

It is advantageous that a base body is provided that the fastening means for connecting the base body to the internal combustion engine is used, that the damping element is connected to the base body and that the component by means of the damping element indirectly with the main body is connectable. It is also advantageous in this case that the damping element is positively connected in a loading direction with the main body. The positioning of the damping element relative to the base body can in this case be effected in particular via an elastic positive fit.

It is also advantageous that the damping element in a direction which is perpendicular to the loading direction, is displaceable relative to the holding element. The direction in which the displaceability is ensured, in this case can be predetermined in particular in the longitudinal direction of the fuel distributor. Here, a purely non-positive connection can be realized. If, for example, contours on the damping element are designed for prefixing, which interact with corresponding contours on the retaining element, or if no special contours are provided, the holding forces acting in the direction, in particular the longitudinal direction, of the fuel distributor can be neglected due to friction with respect to the thermal expansion forces occurring to be viewed as. As a result, a thermal length compensation can be ensured. Another advantage of a purely frictional connection is that during assembly of the component, in particular the fuel distributor, position error can be compensated for the cylinder head to the cylinder head, as this is still no bias and thus a free displacement is possible within certain limits. By a bias of the body and thus acting on the damping element, the position of the damping element relative to the body can then be fixed. Specifically, a clip connection between the holder and the fuel distributor can be realized. In the final assembly, such clips are then stress-free in the direction, in particular the longitudinal direction, which reduces the load on the fastening means and the fuel distributor and enables a correspondingly smaller component dimensioning.

For fixing the fuel distributor, a retaining element is provided, which is connected to the fuel distributor, wherein the retaining element is partially inserted into the damping element. This is an adaptation to the particular application or the respective Fixing point possible. As a result, identical parts can be used advantageously, which represents a significant advantage.

The measures listed in the dependent claims advantageous developments of the holding system specified in claim 1 and the fuel injection system specified in claim 6 are possible. Furthermore, there is the advantage that the holder simplifies the assembly and allows any arrangement.

The holder is used for example for fastening a fuel distributor of a fuel injection system to a cylinder head of an internal combustion engine. The fuel distributor serves as a fuel storage on the internal combustion engine. By the damping element an effective reduction of structure-borne sound transmission is possible. Namely, a contact point between the preferably metallic attachment means and the preferably metallic fuel distributor or a metallic element connected to the fuel distributor can be avoided by the damping element. In addition, a decoupling possible thermal expansion of the attachment is possible. As a result, a simplified design of the fuel distributor and a hedge can be made possible. Thus, disassembly processes can be simplified and the component costs can be reduced.

However, it is also advantageous that the damping element is integrally connected to the base body. Preferably, the cohesive connection can be effected by vulcanization. However, a positive connection, in particular a clipping or clawing, of the damping element in relation to the base body is possible. A frictional connection, in particular a jamming, of the damping element in the body is advantageous.

It is particularly advantageous that the base body has at least one bias limiting gap, which predetermines a certain bias of the base body during assembly, wherein the bias of the Main body can be applied via the fastening means. When applying the bias of the body of Vorspannungsbegrenzungs gap is reduced until it disappears. Then a defined bias of the body is given. This has an advantageous effect in a bias of the damping element. In this case, at the same time a frictional connection between the damping element and the base body is made. This results in a reliable fixation of the component, in particular of the fuel distributor.

It is also advantageous that the base body has a holding part or is connected to a holding part, that the damping element between the holding part and a tubular body of the fuel distributor is arranged and that the holding part and the damping element surround the tubular body at least partially. In this way, a direct fixation of the tubular body and thus the entire fuel distributor can be achieved. This simplifies, inter alia, the design of the fuel distributor, since no special attachment points, additional holder or the like are required at the fuel distributor in this type of attachment.

The damping element is advantageously formed from an elastic material. As a material is preferably a plastic or an elastomer. The damping element is thereby able to compensate for the occurring height tolerances on the internal combustion engine, in particular the cylinder head, and the component, in particular the fuel distributor, and simultaneously absorb the component without play. As a result, during assembly, the loads occurring with respect to the component and the Limited attachment. The material of the damping element can be designed here as a soft contact material. The possibly provided base body can be configured advantageously from a formed sheet steel. Due to the design of the damping element of the preferably soft contact material, the structure-borne sound transmission can be further reduced. In addition, the soft design of the damping element allows the recording of temperature-induced changes in length. In particular, a fuel distributor designed as a fuel distributor strip can thereby stretch, as it were, with temperature changes along its longitudinal axis, virtually unhindered. The stability impairing mechanical stresses in the fuel distributor are thereby avoided.

Brief description of the drawings

• Fig. 1 einen Halter zur Befestigung einer Komponente, insbesondere eines Brennstoffverteilers, an einer Brennkraftmaschine in einer auszugsweisen, schematischen Schnittdarstellung entsprechend einem ersten Ausführungsbeispiel der Erfindung;
• Fig. 2 den in Fig. 1 dargestellten Halter in einer schematischen Schnittdarstellung entlang der mit II bezeichneten Schnittlinie;
• Fig. 3 den in Fig. 1 dargestellten Halter im montierten Zustand;
• Fig. 4 ein Diagramm zur Erläuterung der Funktionsweise des Halters des ersten Ausführungsbeispiels der Erfindung;
• Fig. 5 eine Brennstoffeinspritzanlage mit mehreren Haltern, die zum Befestigen eines Brennstoffverteilers an einer Brennkraftmaschine dienen, in einer schematischen Darstellung entsprechend einer möglichen Ausgestaltung der Erfindung;
• Fig. 6 einen schematischen Schnitt durch die in Fig. 5 dargestellte Brennstoffeinspritzanlage entlang der mit VI bezeichneten Schnittlinie entsprechend einer weiteren möglichen Ausgestaltung der Erfindung;
• Fig. 7 einen anderen Halter und einen rohrförmigen Grundkörper eines Brennstoffverteilers in einer auszugsweisen, schematischen Schnittdarstellung und
• Fig. 8 einen weiteren Halter in einer auszugsweisen, schematischen Schnittdarstellung.

Preferred 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 identical reference numerals. It shows:

• Fig. 1 a holder for fixing a component, in particular a fuel distributor, to an internal combustion engine in an excerpt, schematic sectional view according to a first embodiment of the invention;
• Fig. 2 the in Fig. 1 shown holder in a schematic sectional view along the section line designated II;
• Fig. 3 the in Fig. 1 illustrated holder in the assembled state;
• Fig. 4 a diagram for explaining the operation of the holder of the first embodiment of the invention;
• Fig. 5 a fuel injection system with a plurality of holders, which serve for fastening a fuel distributor to an internal combustion engine, in a schematic representation according to a possible embodiment of the invention;
• Fig. 6 a schematic section through the in Fig. 5 illustrated fuel injection system along the designated VI line of intersection according to another possible embodiment of the invention;
• Fig. 7 another holder and a tubular body of a fuel distributor in a partial, schematic sectional view and
• Fig. 8 another holder in an excerpt, schematic sectional view.

Embodiments of the invention

Fig. 1 shows a holder 1, which is used for fastening a fuel distributor 2 (FIG. Fig. 5 ) to an internal combustion engine 3, in particular a cylinder head 3 of an internal combustion engine 3, serves, in an excerpt, schematic sectional view according to a first embodiment. The holder 1 and the fuel distributor 2 can in this case parts of a fuel injection system 4 ( Fig. 5 ) be. Such a fuel injection system 4 may include a suitable number of holders 1 for attaching the fuel distributor 2 to, for example, a cylinder head 3. However, one or more holders 1 can also serve for fastening other components 2, in particular an injector, to the internal combustion engine 3.

The holder 1 has a main body 5, which is preferably made by forming from a steel sheet. However, the main body 5 may also be formed of other metallic materials. Furthermore, the holder 1 has a fastening means 6, which in this embodiment as a screw is designed. The fastening means 6 is screwed into the cylinder head 3, so that the main body 5 is then directly connected via the fastening means 6 with the cylinder head 3. In addition, a damping element 7 is provided, which is formed of an elastic material. Specifically, the damping element 7 is formed of a soft contact material, in particular a plastic or elastomer.

In this embodiment, a holding element 8 is further provided, which is connected in a suitable manner with the fuel distributor 2 or part of the fuel distributor 2. For example, the holding element 8 with a tubular base body 9 (FIG. Fig. 5 ) of the fuel distributor 2 screwed or welded.

Between the retaining element 8 and the main body 5 no direct contact point is formed. The attachment of the retaining element 8 by means of the damping element 7 on the base body 5. As a result, a certain decoupling is achieved.

In the Fig. 1 is a state during assembly shown. In this case, a displaceability of the retaining element 8 relative to the damping element 7 in a direction 10 (FIG. Fig. 2 ), which is perpendicular to a loading direction 11, allows. As a result, tolerance compensation is ensured during assembly. Further, in this embodiment, on the damping element 7, a projection 12, in particular a rib 12, configured, which engages in a corresponding recess 13 on the retaining element 8. As a result, in the loading direction 11, a positive connection of the damping element 7 to the holding element 8 is configured.

Thus, the fastening means 6 serves for connecting the main body 5 to the internal combustion engine 3. Further, the damping element 7 is connected to the main body 5. And thus the fuel distributor 2 is indirectly connected by means of the damping element 7 with the main body 5 and thereby also indirectly with the internal combustion engine 3.

The damping element 7 may be materially connected to the base body 5. The cohesive connection can be produced for example by vulcanization.

It is also possible that a frictional engagement between the damping element 7 and the main body 5 is formed.

In this embodiment, the main body 5 bent parts 14, 15, which are directed towards each other.

The embodiment of the holder 1 of the first embodiment is hereinafter also with reference to the Fig. 2 and 3 further described.

Fig. 2 shows the in Fig. 1 shown holder 1 in a schematic sectional view along the section line designated II. Fig. 3 shows the in Fig. 1 shown holder in the assembled state. Between the bent parts 14, 15 of the main body 5, a Vorspannungsbegrenzungs gap 16 is configured. The size of the bias limiting gap 16 in this case defines the possible bias of the main body 5 and the damping element 7 during assembly. In this embodiment, also bent parts 17, 18 are provided, between which a Vorspannungsbegrenzungs gap 19 is formed. The bent parts 17, 18 face each other. The bias limiting gap 19 is configured to be the same size as the bias limiting gap 16.

When screwing the fastening means 6 in the cylinder head 3, the base body 5 is deformed. In this embodiment, the fastening means 6 is screwed into the cylinder head 3 in a direction which is perpendicular to the loading direction 11 and perpendicular to the direction 10. The screwing in the direction 20 is limited by the size of the gaps 16, 19. In the Fig. 3 the assembled state is shown, in which the bent parts 14, 15 abut each other. At the same time, the bent parts 17, 18 abut each other. In this state, optionally, a frictional engagement between the base body 5 and the Damping element 7 and / or optionally a frictional engagement between the damping element 7 and the holding element 8 are formed. About the dimensioning of the thickness, the material and the surface of the design of the damping element 7 coming to use contact material, the friction conditions can be defined. Over the surface of the contact material, which is acted upon in each case, the load can be matched to the contact material of the damping element 7 and the structure-borne sound transmission can be reduced. A particularly good reduction of the transmission of structure-borne sound is obtained by preferably very small contact surfaces. By a corresponding structural design, the contact material of the damping element 7 can adapt to the tolerances, which in the Fig. 3 is illustrated by formations 25, 26, 27, 28. By such formations 25, 28 also results in a reliable connection between the support member 8, the damping element 7 and the base body 5. As a result, 11 comparatively large holding forces can be absorbed in particular in the loading direction.

Fig. 4 shows a diagram for illustrating the operation of the holder 1 according to the first embodiment. In the diagram, a path length s for biasing in the direction 20 along an axis 29 of the fastening means 6 is plotted on the abscissa. At the ordinate, the biasing force or the reaction force is plotted as a function of this path length s. The relationship between the biasing force and the path length s is illustrated by a characteristic curve 30. In this embodiment, the characteristic 30 is divided into a first section 31 and a second section 32. The slope of the characteristic 30 here is a measure of the resulting guide size or rigidity of the holder 1 in the direction (screwing) 20. The term of the guide size is to be understood in general, in particular, are also non-linear relationships between the force and the deflection s possible. Specifically, the guide size can be considered in terms of a spring constant. The guide size of a substance, in particular of the material of the damping element 7, can also be determined from the relevant modulus of elasticity and the geometry.

When screwing in the fastening means 6, the gaps 16, 19 decrease so that the effective straightening amount is initially comparatively small. This is described by the first section 31 of the characteristic curve 30. After the path s1, the gaps 16, 19 are closed. As a result, the benchmark increases abruptly. In the characteristic curve 30, therefore, there is a kink from the path length s1. During operation, a further increase in load may occur due to vibrations, which then causes a large reaction force corresponding to the second section 32 of the characteristic curve 30. Thus, by the interaction of the parts 14, 15 and the parts 17, 18, a travel limit is formed. This ensures the required rigidity of the holder 1 for the screw connection.

During assembly of the holder 1, the main body 5 can be slightly spread apart in the region of the damping element 7 in order, to a certain extent, to allow it to be clipped onto the holding element 8. In the clipped-on state, the gaps 16, 19 result first. The screw connection then produces a defined final state.

Fig. 5 shows a fuel injection system 4 with a plurality of holders 1, 1A, 1B, 1C, 1D, 1E, 1F, 1G, which serve for fastening the fuel distributor 2 to an internal combustion engine 3. Here are in the Fig. 5 several ways to attach the holder 1, 1A to 1G shown. Specifically, the holders 1, 1A to 1E can be configured the same or with a slight modification. Thus, a plurality of mounting constellations can be covered with similarly configured holders 1, 1A to 1E. In this embodiment, holding elements 8, 8A, 8B are provided, which are connected in a suitable manner to the tubular base body 9 of the fuel distributor 2. The holder 1 is connected via the retaining element 8 with the tubular base body 9. The holders 1A to 1D are connected to the tubular base body 9 via the holding element 8A. The holder 1E is connected to the tubular base body 9 via the holding element 8B.

The design of the holder 1F, 1G is the example of the holder 1F on the basis of Fig. 7 described in more detail.

Fig. 6 shows the in Fig. 5 illustrated fuel injection system 4 along the designated VI line of intersection according to another possible embodiment of the invention. The holder 1C has a damping element 7C, via which by means of the holding element 8A a connection with the tubular base body 9 is made. Further, in this embodiment, holders 1H, 11 with damping elements 7H, 7I are provided. Retaining elements 8H, 8I are inserted into the damping elements 7H, 7I of the holders 1H, 1I. Specifically, in the holder 1H, a non-lying in the screw plane attachment is realized.

Fig. 7 shows the holder 1F and the tubular base body 9 of the fuel distributor 2 along the in Fig. 5 designated VII section line corresponding to a non-inventive example of the invention. In this example, the main body 5F has a holding part 40. Furthermore, the damping element 7F is arranged between the holding part 40 and the tubular base body 9. The holding part 40 and the damping element 7F surround the tubular base body 9 partially. As a result, the fixation of the fuel distributor 2 can take place directly on its tubular base body 9.

Fig. 8 shows a holder 1J in an excerpt, schematic sectional view according to an example not according to the invention. In this example, a holding member 8J is provided, which is connected to the damping element 7J. The connection can be formed, for example, by vulcanization. The damping element 7J has a continuous recess 41. The continuous recess 41 can be configured in particular as a through-bore 41. A diameter of the through hole 41 is in this case adapted to a diameter of the fastening means 6J. Furthermore, the holding element 8J has a continuous recess 42 which is associated with the continuous recess 41 of the damping element 7J. A cross section of the continuous recess 42, in particular a diameter, is in this case set larger than a cross section, in particular a diameter, the through-hole 41. The fastening means 6 is guided through the through-hole 41 of the damping element 7J and through the through-hole 42 of the retaining element 8J. There is no direct contact between the fastening means 6J and the retaining element 8J.

Thus, the fastening means 6J can be connected to the internal combustion engine 3. The fuel distributor 2 is connected to the damping element 7J via the retaining element 8J. Therefore, the fuel distributor 2 is indirectly connected to the fastening means 6 by means of the retaining element 8J and the damping element 7J.

Thus, unwanted structure-borne sound transmission paths between the internal combustion engine 3 and the fuel distributor 2 can be avoided and, if necessary, a vibration damping and thus noise reduction can be achieved. In this case, the assembly process can be simplified. In addition, thermal expansions can be decoupled from the attachment. In addition, simplifies the design of the fuel distributor 2 and the relevant protection. It also results in a reduction of component costs. Here, a wide range of applications is possible. In particular, the attachment can be realized in combination with injectors suspended in the fuel distributor 2 as well as in combination with displaceable injectors inserted in the fuel distributor 2. All holding functions can thus be realized with a cost-effective holder 1, 1A to 1J. This relates in particular to the fixation of the fuel distributor 2, the securing of a stiff screw fastening, preassembled fastening means 6, a tolerance compensation, an acoustic decoupling and a possible clip function. The main body 5 with the damping element 7 can serve as a holder clip. In this case, the damping element 7 and the main body 5 can be materially connected to each other or be connected to each other as individual parts. A frictional connection due to the friction between the damping element 7 and the retaining element 8 or the damping element 7 and the tubular base body 9 in this case allows a limitation of the stress due to temperature-induced expansion between the fuel distributor 2 and the Internal combustion engine 3. By providing an elastic region, which is realized by the damping element 7, for producing the clip function and a rigid region, which is realized by the base body 5, to ensure the screw connection, an advantageous embodiment in a component is possible. In this case, further functions, such as the positioning of the screws or similar components, such as a wiring harness, can be integrated. In addition, defined contact surface ratios to the fuel distributor 2 can be realized in an embodiment of the holder made of a plurality of materials for the reduction of structure-borne sound transmission. In this case, preferably very soft contact points can be realized by the use of plastics or elastomers. Due to the reliable limitation of the bias of the damping element 7 whose permanent function can be ensured.

In an advantageous embodiment of the holder 1 allows in a freely selectable direction 20, the attachment of the fuel distributor 2 to the internal combustion engine 3. Here, especially the direction 20 define a mounting direction 20. In particular, the mounting direction 20 can be varied by varying the holder 2 or the holding element 8 in all spatial directions.

In one possible embodiment, it is advantageous that the base body 5 and the damping element 7 form a component 5, 7 and that a rigid screw connection is predetermined via at least one gap 16, 19 of the base body 5. Here, the maximum torque is reached, so to speak abruptly at the end of the screwing.

The fuel distributor 2 can thus be designed without holes or receptacles for attachment to the internal combustion engine 3. For this function for attachment is already integrated in the main body 5 of the holder. Thus, the fuel distributor 2 can also be manufactured with a high degree of freedom with regard to possible attachment images, since the mounting of the holder 1 takes place only after the completion of the fuel distributor and allows many attachment possibilities.

The invention is not limited to the described embodiments.

Claims (7)

1. Holding system having a component (2), in particular a fuel distributor, having a holder (1) for fastening said component (2) to an internal combustion engine (3), having a fastening means (6) and having a damping element (7), wherein the fastening means (6) is connectable to the internal combustion engine (3), and wherein the component (2) is connected to the fastening means (6) indirectly via at least the damping element (7), wherein the holder (1) has a main body (5), at least one holding element (8) is provided which projects from the component (2), and the damping element (7) is situated between the main body (5) of the holder (1) and the holding element (8), wherein the holding element (8) is partially inserted into the damping element (7) such that no direct point of contact is formed between the holding element (8) and the main body (5), wherein the fastening means (6) serves for connecting the main body (5) to the internal combustion engine (3), wherein the damping element (7) is connected in positively locking fashion in a load direction (11) to the holding element (8), characterized in that, during the installation of the damping element (7), the damping element (7) is displaceable relative to the holding element (8) in a direction (10) perpendicular to the load direction (11), and in that the main body (5) is a deformed metallic plate.
2. Holding system according to Claim 1,
   characterized
   in that the damping element (7) is cohesively connected to the main body (5).
3. Holding system according to Claim 2,
   characterized
   in that the main body (5) is formed from a metallic material.
4. Holding system according to either of Claims 2 and 3,
   characterized
   in that the main body (5) has at least one preload-limiting gap (16, 19) which, during an assembly process, predefines a certain preload of the main body (5) and/or of the damping element (7), wherein the preload of the main body (5) or of the damping element (7) can be imparted by the fastening means (6),
   and/or
   in that the main body (5) and the damping element (7) form one component (5, 7), and in that, by means of at least one gap (16, 19) of the main body (5), a fixed screw-tightening point is predefined.
5. Holding system according to one of Claims 1 to 4, characterized
   in that the damping element (7) is formed from an elastic material.
6. Fuel injection system (4) having a fuel distributor (2) and having at least one holding system according to one of Claims 1 to 5, which has a holder

   (1) and which serves for fastening the fuel distributor

   (2) to an internal combustion engine (3).
7. Fuel injection system according to Claim 6, characterized
   in that the holder (1) permits the fastening of the fuel distributor (2) to the internal combustion engine (3) in a freely selectable direction (20).

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