Holder system for fixing a component to a combustion engine

State of the art

p0001The invention relates to a holder for mounting at least one component, in particular a fuel distributor, in an internal combustion engine. Specifically, the invention relates to the field of fuel injection systems of internal combustion engines.

p0002From the <patcit id="pcit0001" dnum="US7793639B2"><text>US 7,793,639 B2</text></patcit> a device is known, which serves to vibrations of a fuel distributor for noise reduction in an internal combustion engine in reference. The apparatus includes a support bracket that serves for fastening the fuel distributor on a cylinder head.

Disclosure of the Invention

p0003The holder according to the invention with the features of claim 1 and the fuel injection system according to the invention with the features of claim 9 have the advantage that an improved vibration damping is ensured over the service life. Specifically, there is the advantage that an effective noise attenuation is guaranteed over the lifetime.

p0004The measures specified in the dependent claims, advantageous refinements of the features specified in claim 1 and the holder specified in claim 9 fuel injection system are possible. Furthermore, there is the advantage that the holder simplifies installation and any arrangement allows.

p0005The holder is used for example for attaching a fuel distributor of a fuel injection system on a cylinder head of an internal combustion engine. The fuel manifold serves as fuel storage to the internal combustion engine. By the damping element an effective reduction of structure borne sound transmission is possible. By the damping element can be avoided namely a contact point between the preferably metallic fasteners and preferably metallic fuel distributor or connected to the fuel manifold metallic element. In addition, a decoupling possible thermal expansion of the mounting is possible. This allows a simplified design of the fuel distributor and a hedge are possible. Thus, dismantling processes can be simplified and the component cost can be reduced.

p0006It is advantageous that a base body is provided that the fastening means for connecting the base body is used with the internal combustion engine, that the damping element is connected to the base body and in that the component by means of the damping element is indirectly connected to the basic body. It is advantageous here, furthermore, that the damping element is connected in a loading direction positively to the base body. The positioning of the damping element relative to the base body can be made here in particular of an elastic form-fit.

p0007It is also advantageous that the damping element, is displaceable relative to the holding element in a direction which is perpendicular to the load direction. The direction in which the displacement is ensured in this case may be predetermined in particular in the longitudinal direction of the fuel distributor. Here, a purely positive connection can be realized. Are used for pre-fixing, for example, contours of the damping element designed to cooperate with corresponding contours on the holding element or any special contours are provided, then the in the direction, in particular the longitudinal direction of the fuel distributor, acting holding force by friction of withstanding the thermal expansion forces to be negligible to be viewed as. This allows a thermal length compensation be guaranteed. Another advantage of a purely non-positive connection is that during assembly of the component, in particular the fuel distributor, to the cylinder head position error to the cylinder head can be compensated for, since in this case no bias is thus a free displaceability is made possible within certain limits. the position of the damping element can then be fixed relative to the base body by a bias voltage of the base body and thus loading of the damping element. Specifically, a clip connection between the holder and the fuel distribution can be realized. In the final assembly of clips are then in the direction, in particular the longitudinal direction, stress-free, which reduces the load on the fastener and the fuel distributor and a correspondingly smaller dimensioning of components allows.

p0008However, it is also advantageous that the damping element is integrally connected to the base body. Preferably, the bonded connection can be done by Aufvulkanisierung. However, also a positive connection, in particular a clipping or clawing, the damping element with respect to the base body is possible. Also, a non-positive connection, in particular a clamping, the damping element in the base body is advantageous.

p0009Specifically, it is advantageous that the base body has at least one Vorspannungsbegrenzungs-gap, a certain prestress of the base body defines at an installation, wherein the bias of the base body via the fastening means can be applied. When applying the bias voltage of the base of Vorspannungsbegrenzungs-gap is reduced until it disappears. Then a defined bias of the base body is given. This affects advantageously in a bias voltage of the damping element from. Here, a non-positive connection between the damping element and the base body is made at the same time. This results in a reliable fixation of the component, in particular the fuel distributor.

p0010For fastening the fuel distributor, a retaining element may be provided which is connected to the fuel distributor, wherein the retaining element is partially inserted into the damping element. This adaptation to the respective application or the respective mounting location is possible. This identical parts can be used, which is an important advantage in an advantageous manner.

p0011It is also advantageous that the base body has a holding member or is connected to a holding part, that the damping element between the holding part and a tubular base body of the fuel distributor is arranged and that the holding part and the damping element engage around the tubular body at least partially. In this way, a direct fixing of the tubular base body and thus of the entire fuel distributor can be obtained. This simplifies inter alia the design of the fuel distributor, since with this type of attachment, no special attachment locations additive holder or the like are charged on the fuel distributor.

p0012The damping element is formed advantageously of a resilient material. The material is preferably suitable plastic or an elastomer. The damping element is thereby capable of occurring height tolerances of the internal combustion engine, especially the cylinder head, and the component, in particular the fuel manifold, compensate and simultaneously accommodate the component without play. Thereby the stresses that occur with respect to the component and the fastening means are limited during assembly. The material of the damping element can in this case be designed as a soft contact material. The optionally provided base body can be designed in an advantageous manner from a formed sheet steel. Due to the configuration of the damping element of the preferably soft contact material, the structure-borne noise can be further reduced. In addition, the soft design of the damping element allows recording of temperature-induced changes in length. Specifically, a configured as a fuel rail fuel distributor can virtually extend unhindered thereby when the temperature changes along its longitudinal axis. The stability impairing mechanical stresses in the fuel distributor are avoided.

Brief Description of Drawings

p0013Preferred embodiments of the invention are explained in more detail in the following description with reference to the accompanying drawings in which corresponding elements with matching reference numerals are provided to. It shows:<ul><li><figref idrefs="f0001">Fig. 1</figref> a bracket for mounting a component, in particular a fuel distributor, to an internal combustion engine, in a partial, schematic sectional view according to a first embodiment of the invention;</li><li><figref idrefs="f0001">FIG. 2</figref> the in <figref idrefs="f0001">Fig. 1</figref> Holder shown in a schematic sectional view taken along section line denoted by II;</li><li><figref idrefs="f0002">Fig. 3</figref> the in <figref idrefs="f0001">Fig. 1</figref> Holder shown in the assembled state;</li><li><figref idrefs="f0002">Fig. 4</figref> a diagram for explaining the operation of the holder of the first embodiment of the invention;</li><li><figref idrefs="f0003">Fig. 5</figref> a fuel injection system having a plurality of holders which serve for securing a fuel distributor of an internal combustion engine, in a schematic representation, according to a possible embodiment of the invention;</li><li><figref idrefs="f0003">Fig. 6</figref> a schematic section through the in <figref idrefs="f0003">Fig. 5</figref> illustrated fuel injection system along the section line marked VI in accordance with a further possible embodiment of the invention; </li><li><figref idrefs="f0004">Fig. 7</figref> a holder and a tubular body of a fuel distributor, in a partial, schematic sectional view according to a second embodiment of the invention and</li><li><figref idrefs="f0004">Fig. 8</figref> a holder, in a partial, schematic sectional view according to a third embodiment of the invention.</li></ul>

Embodiments of the invention

p0014<figref idrefs="f0001">Fig. 1</figref> shows a holder 1 that serves for mounting of a fuel distributor 2 (<figref idrefs="f0003">Fig. 5</figref>) To an internal combustion engine 3, in particular a cylinder head 3 of an internal combustion engine 3, is used, a part-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 (<figref idrefs="f0003">Fig. 5</figref>) be. Such a fuel injection system 4 may comprise an appropriate number of holders 1, to secure the fuel rail 2, for example on a cylinder head. 3 One or more holders 1 can equally for attaching other components 2, in particular an injector, used to the internal combustion engine. 3

p0015The holder 1 has a Grundkörp on he 5, which is preferably made ​​by forming from a sheet steel. The base body 5 can however also be made ​​of other metal materials. Further, the holder 1 a fastening means 6 which is configured in this embodiment as a screw. The fastener 6 is screwed into the cylinder head 3 so that the base is 5 then connected via the fastening means 6 directly to the cylinder head. 3 In addition, a damping element 7 is provided which is formed of an elastic material. Specifically, the damping member 7 is formed of a soft contact material, in particular a plastic or elastomer.

p0016In this embodiment, a holding element 8 is further provided, which is suitably connected to the fuel distributor 2 or is part of the fuel distributor second For example, the holding element 8 with a tubular base body 9 (<figref idrefs="f0003">Fig. 5</figref>) Of the fuel distributor 2 bolted or welded.

p0017Between the holding member 8 and the base part 5 is no direct contact point is formed. The attachment of the holding member 8 is effected by means of the damping element 7 on the basic body 5. In this way, a certain degree of insulation is obtained.

p0018In the <figref idrefs="f0001">Fig. 1</figref> is illustrated a state during assembly. Here, a displaceability of the holding element 8 relative to the damping member 7 in a direction 10 (<figref idrefs="f0001">FIG. 2</figref>), Which is perpendicular to a loading direction 11 allows. This tolerance compensation is ensured during assembly. Further, in this embodiment, on the damping member 7, a projection 12, in particular a rib 12 configured to engage a corresponding recess 13 on the holding element. 8 Characterized in the loading direction 11, a positive connection of the damping element 7 is embodied with the holding element. 8

p0019Thus, the fastening means 6 serves to connect the base body 5 with the internal combustion engine 3. Moreover, the damper member 7 is connected to the base body. 5 And thus the fuel distributor 2 is indirectly connected to the base body 5 and thereby also indirectly connected to the internal combustion engine 3 by means of the damping element. 7

p0020The damping element 7 may be firmly bonded to the base body. 5 The integral connection can be produced for example by vulcanizing.

p0021It is also possible that a frictional engagement between the damping element 7 and the base 5 is formed.

p0022In this embodiment, the base body 5 has bent parts 14, 15 which are facing each other.

p0023The embodiment of the holder 1 of the first embodiment is hereinafter also with reference to the <figref idrefs="f0001">FIG. 2</figref> and <figref idrefs="f0002">3</figref> further described.

p0024<figref idrefs="f0001">FIG. 2</figref> shows in <figref idrefs="f0001">Fig. 1</figref> illustrated holder 1 in a schematic sectional view taken along section line denoted by II. <figref idrefs="f0002">Fig. 3</figref> shows in <figref idrefs="f0001">Fig. 1</figref> Holder shown in the mounted state. Between the bent parts 14, 15 of the base body 5, a Vorspannungsbegrenzungs-gap 16 is configured. The size of the gap 16 defined Vorspannungsbegrenzungs-in this case the possible bias of the base 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 Vorspannungsbegrenzungs-gap 19 is correspondingly large as the gap 16 Vorspannungsbegrenzungs-configured.

p0025When screwing the fastener 6 in the cylinder head 3 of the base body 5 is deformed. In this embodiment, the fastening means 6 is screwed in one direction in the cylinder head 3, which is the one perpendicular to the direction of loading 11 and the other perpendicular to the direction 10th Screwing in the direction 20 is limited by the size of the column 16, 19th In the<figref idrefs="f0002">Fig. 3</figref> is shown the assembled state in which the bent parts 14, 15 abut one another. Here, at the same time push the bent parts 17, 18 to one another. In this state, may optionally be formed 8 also a frictional connection between the base body 5 and the damping member 7 and / or optionally a frictional engagement between the damping element 7 and the holding element. On the dimensioning of the thickness, the material and the surface of the used next to the configuration of the damping member 7 contact material, the friction conditions can be defined. Over the area of ​​the contact material, which is in each case applied, the load can be matched to the contact material of the damping element 7 and the body sound transmission can be reduced. A particularly good reduction of impact sound transmission results here by preferably very small contact areas. By an appropriate design configuration, the contact material of the damping element 7 can adjust the tolerances, which in the<figref idrefs="f0002">Fig. 3</figref> is illustrated by shaped portions 25, 26, 27, 28th Such formations 25, 28 is also a reliable connection between the holding element 8, the damping element 7 and the main body 5. This gives 11 relatively large holding forces can be absorbed in particular in the loading direction.

p0026<figref idrefs="f0002">Fig. 4</figref> 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 fastener 6 is plotted on the x-axis. On the ordinate the biasing force or the reaction force is s plotted as a function of the path length. The relationship between the biasing force and the path length s is illustrated by a characteristic 30th In this embodiment, the characteristic curve 30 is divided into a first section 31 and a second portion 32nd The slope of the curve 30 is in this case a measure of the resulting benchmark or stiffness of the holder 1 in the direction (screwing) 20. The term of the benchmark here is generally to be understood, in particular, are also non-linear relationship between the force and the deflection s possible. Specifically, the benchmark can be considered in terms of a spring constant. The benchmark of a substance, in particular of the material of the damping element 7 can also be determined from the relevant elastic modulus and geometry.

p0027When screwing the fastening means 6 to reduce the gaps 16, 19, so that the effective benchmark initially relatively low. This is described by the first portion 31 of the characteristic curve 30th Following the path s1 column 16, 19 are closed. Thus, the benchmark is skyrocketing. In the characteristic curve 30 therefore results in a bend from the path s1. In operation, there may be due to vibrations to a further increase in load, the then 30 caused according to the second section 32 of the characteristic curve a large reaction force. Thus is formed by the interaction of the parts 14, 15 as well as the parts 17, 18 has a travel limiter. Thus, the required rigidity of the holder 1 is ensured for the screw.

p0028During the assembly of the holder 1, the base body 5 can be spread apart slightly in the region of the damping member 7 to a certain extent to allow a clip-on, the holding element eighth In clipped condition then result initially the gaps 16, 19. The screw is then given a defined end state.

p0029<figref idrefs="f0003">Fig. 5</figref> 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 of an internal combustion engine 3rd Here, in the<figref idrefs="f0003">Fig. 5</figref> several options for mounting the holder 1, 1A to 1G. Specifically, the holder 1, 1A to 1E can hereby be configured identically or with minor modification. Thus, can be covered with the same designed holders 1, 1A to 1E, a plurality of mounting configurations. In this embodiment, holding members 8, 8A, 8B are provided, which are suitably connected to the tubular main body 9 of the fuel distributor second The holder 1 is connected to the holding element 8 with the tubular body. 9 The holder 1A to 1D are connected through the holding member 8A with the tubular basic body. 9 The holder 1E is connected by the holding element 8B with the tubular basic body. 9

p0030The embodiment of the holder 1F, 1G, using the example of the holder 1F on the basis of <figref idrefs="f0004">Fig. 7</figref> described in detail.

p0031<figref idrefs="f0003">Fig. 6</figref> shows in <figref idrefs="f0003">Fig. 5</figref> illustrated fuel injection system 4 along the cutting line marked VI in accordance with a further possible embodiment of the invention. The holder 1C has a damping member 7c, over which there is a connection to the tubular body 9 by means of the supporting member 8A. Further, in this embodiment, holder 1H, 1I provided with damping elements 7H, 7I. Retaining elements 8H, 8I are in the damping elements 7H, 7I holder 1H, 1I inserted. Especially when the holder 1H attachment not lying in the screw plane is realized.

p0032<figref idrefs="f0004">Fig. 7</figref> 1F shows the holder and the tubular main body 9 of fuel distributor 2 along the in <figref idrefs="f0003">Fig. 5</figref> with VII section line denoted according to a second embodiment of the invention. In this embodiment, the main body 5F has a holding part 40th Furthermore, the damping element 7F between the holding part 40 and the tubular main body 9 is arranged. The holding member 40 and the damping element 7F grip the tubular body 9 partially. This can be done directly at its tubular body 9, the fixation of the fuel distributor. 2 It is particularly advantageous that the fuel distributor 2 in this respect no holding member is required on the fixation of the tubular base body 9 is possible.

p0033<figref idrefs="f0004">Fig. 8</figref> shows a holder 1J, in a partial, schematic sectional view according to a third embodiment. In this embodiment, a holding member 8J is provided, which is connected to the damping element 7J. The compound may for example be formed by vulcanizing. The damping element 7J has a continuous recess 41st The through opening 41 can be configured in particular as a through hole 41st A diameter of the through hole 41 is in this case adapted to a diameter of the fastening 6J. Further, the holding member 8J has a continuous recess 42 which is associated with the through opening 41 of the damping element 7J. A cross section of the through recess 42, in particular a diameter, is predefined in this case is larger than a cross-section, in particular a diameter of the through recess 41. The fastening means 6 is guided through the through opening 41 of the damping element 7J and through the through opening 42 of the holding element 8J , In this case, there is no direct contact between the attachment means and the retaining element 6J 8J.

p0034Thus, the fastening means 6J is connectable to the internal combustion engine 3rd The fuel manifold 2 is connected via the holding element 8J with the damping element 7J. Therefore, the fuel manifold 2 by means of the retaining element and the damping element 8J 7J is indirectly connected to the fastening means 6th

p0035Thus unwanted body sound transmission paths between the internal combustion engine 3 and the fuel manifold 2 can be avoided, and optionally a vibration damping and thus noise reduction can be achieved. Here, also, the assembly process can be simplified. Furthermore, thermal expansions can be decoupled from the attachment. In addition, the design of the fuel distributor 2 and the related hedging simplified. The result is also a reduction in component costs. Here, a wide range of applications is possible. In particular, the attachment can be realized in combination with suspended in the fuel distributor 2 injectors and in combination with inserted in the fuel distributor 2, movable injectors. All support functions can therefore with a cost-holder 1, 1A can be realized through 1J. This concerns in particular the fixing of the fuel distributor 2, ensuring a rigid screw joint, preassembled fasteners 6, tolerance compensation, an acoustic isolation and a possible clip function. The base body 5 with the damping element 7 can in this case serve as a retainer clip. Here, the damping member 7 and the base body 5 can be firmly bonded to each other or be connected to one another as individual parts. A frictional connection due to the friction between the damping element 7 and the holding element 8 and the damping element 7 and the tubular main body 9 permits each limiting the voltage stress due to temperature related expansion between the fuel distributor 2 and the internal combustion engine 3. By providing a resilient portion, the is realized by the damping element 7, for the preparation of the clip function and a rigid portion, which is realized through the basic body 5, for ensuring an advantageous embodiment of the screw connection in a component is possible. Here, other features such as the positioning of the screws or similar components, such as a wire harness, to be integrated. In addition, can be realized defined contact surface ratios for fuel distributor 2 in an embodiment of the holder of multiple materials to reduce the structure-borne sound transmission. This can be realized through the use of plastics or elastomers preferably very soft contact points. Due to the reliable limitation of the bias of the damping member 7 whose long-term operation can be ensured.

p0036In one advantageous embodiment of the holder allows 1 in an arbitrary direction 20 fastening the fuel distributor 2 to the internal combustion engine 3. Here, specifically the direction 20 define a mounting direction 20th In particular, the mounting direction 20 can be varied by variation of the holder 2 and the holding member 8 in all spatial directions.

p0037In one possible embodiment, it is advantageous that the base body 5 and the damper member 7 is a member 5, and 7 form that via at least one gap 16, 19 of the base body 5, a rigid screw joint is predetermined. Here, the maximum torque is achieved as it were abruptly at the end of the screwing.

p0038The fuel distributor 2 can thus be configured without drilling or shots for attachment to the engine. 3 Because this feature for mounting is already integrated into the basic body 5 of the holder. Thus, the fuel distributor 2 can also be produced with a high freedom in more potential fixing images, since the assembly of the holder 1 takes place only after the completion of the fuel distributor and many mounting options allows.

p0039The invention is not limited to the described embodiments.