Retainer for fastening a fuel distributor to an internal combustion engine and system having such a retainer

Abstract

A retainer for fastening a component, especially a fuel distributor, via a holding element to an internal combustion engine includes: decoupling elements, a fastening body and a fastening element. The fastening body is fastened to the internal combustion engine with the aid of the fastening element. In addition, the holding element is fastened to the fastening body via the decoupling elements. Moreover, a preloading element is provided that is joined to the fastening body, preloading of the decoupling elements being set by way of a predefined position of the preloading element relative to the fastening body in which the preloading element is joined to the fastening body.

Claims

1. A retainer for fastening a component via a holding element to an internal combustion engine, comprising: at least one decoupling element; a fastening body surrounding at least a portion of a fastening element; and a preloading element; wherein: the fastening body is configured to be fastened to the internal combustion engine with the aid of the fastening element; the holding element is configured to be fastened to the fastening body via the at least one decoupling element; the preloading element is configured to be joined at least indirectly to the fastening body; and a preloading force on the at least one decoupling element is set, independently of a force used to fasten the fastening body to the internal combustion engine using the fastening element, by a specifiable position of the preloading element relative to the fastening body in which the preloading element is joined to the fastening body.

2. The retainer as recited in claim 1, wherein the preloading element has an inner contact surface with which the preloading element abuts against an outer surface of the fastening body.

3. The retainer as recited in claim 2, wherein: the fastening body has at least one depression on the outer surface; the preloading element has a deformable projection; and the deformable projection and the at least one depression of the fastening body are shaped in such a way that the preloading element is configured to be joined to the fastening body by flanging.

4. The retainer as recited in claim 2, wherein the inner contact surface of the preloading element and the outer surface of the fastening body are shaped to form a sliding fit between the inner contact surface of the preloading element and the outer surface of the fastening body.

5. The retainer as recited in claim 2, wherein the inner contact surface of the preloading element and the outer surface of the fastening body are shaped to enable the preloading element to be joined to the fastening body by a press fit formed between the inner contact surface of the preloading element and the outer surface of the fastening body.

6. The retainer as recited in claim 2, further comprising: a supporting element which is joined to the fastening body, wherein the decoupling element is preloaded at least indirectly against the supporting element by the preloading element.

7. The retainer as recited in claim 2, wherein at least one of (i) the decoupling element surrounds the fastening body, and (ii) the decoupling element is shaped as an at least approximately rectangularly bent, ring-like decoupling element.

8. A system, comprising: a component; a holding element to hold the component; and a retainer configured to fasten the component to an internal combustion engine, the retainer including: at least one decoupling element; a fastening body surrounding at least a portion of the fastening element; and a preloading element; wherein: the fastening body is configured to be fastened to the internal combustion engine with the aid of the fastening element; the holding element is configured to be fastened to the fastening body via the at least one decoupling element, and the holding element is joined to the component; the preloading element is configured to be joined at least indirectly to the fastening body; and a preloading force on the at least one decoupling element is set, independently of a force used to fasten the fastening body to the internal combustion engine using the fastening element, by a specifiable position of the preloading element relative to the fastening body in which the preloading element is joined to the fastening body.

9. The system as recited in claim 8, wherein one of: (i) the preloading element is joined to the fastening body by at least one of welding, flanging, and a press fit; or (ii) the preloading element is screwed with an internal thread of the preloading element onto an external thread of the fastening body.

10. The system as recited in claim 8, wherein the at least one decoupling element is configured such that, at least along a preloading direction in which the at least one decoupling element is preloaded by way of the position of the preloading element relative to the fastening body, a non-linear spring characteristic is predefined which describes a dependency of a restoring force, acting on the holding element, on a deflection of the holding element relative to the fastening body.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a system having a retainer and a fuel distributor and an internal combustion engine in a partial, schematic sectional view according to a first exemplary embodiment of the present invention.

(2) FIG. 2 shows a system having a retainer and a fuel distributor and an internal combustion engine in a partial, schematic sectional view according to a second exemplary embodiment of the present invention.

(3) FIG. 3 shows a retainer of the system shown in FIG. 1 in a partial, schematic sectional view according to a third exemplary embodiment of the invention.

(4) FIG. 4 shows a retainer of the system shown in FIG. 1 in a partial, schematic sectional view according to a fourth exemplary embodiment of the invention.

(5) FIG. 5 shows the retainer shown in FIG. 1 in a partial, schematic representation from the direction of view denoted by V according to a fifth exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

(6) FIG. 1 shows a system 1 having a retainer 2 and a fuel distributor 3, especially a fuel distributor rail 3, and a portion of an internal combustion engine 4, especially a cylinder head 4, in a partial, schematic sectional view according to a first exemplary embodiment. System 1 is preferably a fuel-injection system 1 or a portion of a fuel-injection system 1.

(7) Retainer 2 has a fastening body 5, a fastening means 6, a holding element 7, decoupling elements 8, 9, and a preloading element 10. Fastening means 6 is screwed into a threaded bore 11. A collar 12 of head 13, which takes the form of a screw head 13, abuts against an end face 14 of fastening body 5. In this manner, fastening body 5 is acted upon with its bottom side 15 against a surface 16 of internal combustion engine 4. The fastening force is generated here by a tightening torque of fastening means 6 in the form of fastening screw 6. In so doing, a force transmission adhesion comes about via fastening means 6 and fastening body 5, which is illustrated by a closed curve 17.

(8) Preloading element 10 has an inner contact surface 20. Preloading element 10 is placed against an outer surface 21 of fastening body 5. In this context, preloading element 10 abuts with its inner contact surface 20 against outer surface 21 of fastening body 5. During assembly, preloading element 10 is displaceable in and counter to a preloading direction 22 relative to fastening body 5, in the course of which, it is guided on outer surface 21. In this connection, preloading direction 22 is oriented parallel to a longitudinal axis 23 of fastening means 6.

(9) In addition, retainer 2 has a supporting element 24, which in this exemplary embodiment, is encompassed by fastening body 5. In a modified embodiment, supporting element 24 may also be joined to fastening body 5. Bottom side 15 is formed at least partially on supporting element 24 in this exemplary embodiment. Thus, supporting element 24 is braced against surface 16 of internal combustion engine 4.

(10) Preloading element 10 has a formation 25 realized as a depression. In addition, decoupling element 8 has a formation 26 realized as bulged formation 26. Decoupling element 8 is inserted with bulged formation 26 into preloading element 10, so that a form-locking connection is created. Formations 25, 26 may also be shaped so as to match each other in another way, in order to create a form-locking connection.

(11) Supporting element 24 has a formation 27 realized as a depression. Decoupling element 9 also has a formation 28 which is bulged. Decoupling element 9 engages with bulged formation 28 in formation 27, so that a form-locking connection is created. Holding element 7 is situated between decoupling elements 8, 9, an upper side 29 of holding element 7 being at least approximately flat in this exemplary embodiment. Furthermore, a lower side 30 of holding element 7 is also at least approximately flat. Between decoupling element 8, which abuts against upper side 29, and holding element 7, a friction locking is thus formed in a direction 31 perpendicular to preloading direction 22. Correspondingly, a friction locking is also formed in direction 31 between decoupling element 9, which abuts against lower side 30, and holding element 7. A sufficient retention force in and counter to direction 31 is able to be generated here within certain limits via preloading of decoupling elements 8, 9. If desired, a form-locking connection may also be formed between holding element 7 and at least one of decoupling elements 8, 9, as described by way of example on the basis of formations 25 through 28.

(12) During assembly, a suitably selected assembly force is applied to preloading element 10 in preloading direction 22. Decoupling elements 8, 9 are thereby preloaded. In so doing, utilization is made of the fact that preloading element 10 is displaceable relative to fastening body 5, so that the placement of preloading element 10 relative to fastening body 5 is specifiable upon assembly. In this predefined placement or position of preloading element 10 relative to fastening body 5, preloading element 10 is then joined to fastening body 5. The preloading of decoupling elements 8, 9 is thereby set. For example, within the course of a series production, in this way a predefined preloading of decoupling elements 8, 9 may be set, regardless of component variances occurring. In addition, a desired preloading may also be set individually in terms of the specific application case. Furthermore, a modular assembly may also be realized where, for example, holding element 7 and/or decoupling elements 8, 9 is/are dimensioned differently in view of the specific application case. The desired preloading may then always be set when working with such a modular assembly, as well.

(13) The force transmission from preloading element 10 via decoupling element 8, holding element 7 and decoupling element 9 to supporting element 24 is closed via fastening body 5, as illustrated by closed curve 32. The preloading of decoupling elements 8, 9 and the impingement of decoupling elements 8, 9 during operation in response to a deflection of holding element 7 relative to fastening body 5 is therefore independent of the attachment of fastening body 5 to internal combustion engine 4, as illustrated by closed curve 17.

(14) When the predefined preloading of decoupling elements 8, 9 is set by the placement of preloading element 10, preloading element 10 is then preferably fixed in its position. This may be accomplished by a material-locking and/or form-locking connection.

(15) In a modified embodiment, a press fit may also be formed between preloading element 10 and fastening body 5. For this purpose, inner contact surface 20 of preloading element 10 and outer surface 21 of fastening body 5 are shaped in such a way that after assembly, preloading element 10 is joined to fastening body 5 by the press fit formed between inner contact surface 20 of preloading element 10 and outer surface 21 of fastening body 5. This may also be combined with a further type of connection, depending on the application case. Decoupling elements 8, 9 are then preloaded by preloading element 10 against supporting element 24 over the operational lifetime.

(16) In this exemplary embodiment, decoupling elements 8, 9 surround fastening body 5 circumferentially. Decoupling elements 8, 9 are shaped here as ringlike decoupling elements 8, 9 and preferably are axially symmetric relative to longitudinal axis 23. At least a portion of holding element 7 in the area of interaction with decoupling elements 8, 9 is preferably ringlike, as well. Correspondingly, preloading element 10 and supporting element 24 are preferably also axially symmetric relative to longitudinal axis 23.

(17) In forming the connection between preloading element 10 and fastening body 5, it is also possible during assembly to predefine a distance 33 between preloading element 10 and supporting element 24. Upon assembly, the preloading may then be set in a manner that the assembly device moves preloading element 10 into the position, predefined by distance 33, relative to fastening body 5. In particular, distance 33 may be a defined measure of press-in 33, if preloading element 10 is joined to fastening body 5 by a press fit. Thus, a path-controlled adjustment of the preloading of decoupling elements 8, 9 is possible.

(18) FIG. 2 shows a system having a retainer 2 and a fuel distributor 3 and an internal combustion engine 4 in a partial, schematic sectional view according to a second exemplary embodiment. In this exemplary embodiment, fastening body 5 has at least one depression 40 on its outer surface 21 In addition, preloading element 10 has a deformable projection 41 which is provided at least in the area of depression 40 of fastening body 5 on outer surface 21 of fastening body 5. Deformable projection 41 of preloading element 10 preferably surrounds outer surface 21 of fastening body 5 circumferentially. By preference, inner contact surface 20 of preloading element 10 abuts against outer surface 21 of fastening body 5. However, inner contact surface 20 may also be set apart somewhat from outer surface 21.

(19) During assembly, first of all, an assembly device acts upon preloading element 10 in preloading direction 22. This may be accomplished in force-controlled fashion. A path-controlled adjustment of the preloading of decoupling elements 8, 9 may also be attained over a defined distance 33. In the predefined position of preloading element 10 relative to fastening body 5, deformable projection 41 is deformed somewhat into depression 40 during assembly by a flanging tool 42, which is affixed in the area of depression 40, and to which a flanging force is applied in a direction 43. Thus, a form-locking connection is realized by flanging. In the predefined position of preloading element 10 relative to fastening body 5 in which preloading element 10 is joined to fastening body 5 by flanging, the preloading of decoupling elements 8, 9 is set after assembly.

(20) FIG. 3 shows a retainer 2 of system 1 shown in FIG. 1 in a partial, schematic sectional view according to a third exemplary embodiment. In this exemplary embodiment, an assembly force is first applied to preloading element 10 in preloading direction 22. The preloading of decoupling elements 8, 9 is thereby set. Preloading element 10 is then joined to fastening body 5 by a welded seam 44. Thus, a material-locking connection of preloading element 10 to fastening body 5 is formed in the predefined position of preloading element 10 relative to fastening body 5.

(21) FIG. 4 shows a retainer 2 of system 1 shown in FIG. 1 in a partial, schematic sectional view according to a fourth exemplary embodiment. In this exemplary embodiment, fastening body 5 has an external thread 45 on its outer surface 21. In addition, preloading element 10 has an internal thread 46 on an inner surface 20′. Preloading element 10 is screwed with internal thread 46 onto external thread 45 of fastening body 5. A form-locking connection is created via the threaded connection between preloading element 10 and fastening body 10. In this case, adjustability is possible after a certain time of service or an anticipated aging. Here, preloading element 10 may be screwed onto fastening body 5 to a predefined distance 33. The preloading of decoupling elements 8, 9 is thus adjustable. If desired, preloading element 10 may also be fixed in its position in suitable manner.

(22) FIG. 5 shows the retainer, illustrated in FIG. 1, in a partial, schematic representation from the direction of view denoted by V according to a fifth exemplary embodiment. In this exemplary embodiment, a non-axially symmetric design is realized. In this case, preloading element 10 and decoupling elements 8, 9 are at least approximately rectangularly bent and ringlike. Between inner contact surface 20 of preloading element 10 and outer surface 21 of fastening body 5, a sliding fit is formed by suitable shaping. In the predefined position, preloading element 10 may then be fixed in position in suitable manner on fastening body 5.

(23) By a suitable formation of at least one decoupling element 8, 9, a non-linear spring characteristic may be predefined, especially along preloading direction 22, which describes a dependency of a restoring force, acting on holding element 7, on a deflection of holding element 7 relative to fastening body 5. For example, in the case of decoupling element 8 described with reference to FIG. 3, a chamfer 50 is provided, whereby upon adjustment of holding element 7 counter to preloading direction 22, the spring constant gradually increases, since chamfer 50 is increasingly overcompressed. Therefore, by the formation of decoupling element 8, at least along preloading direction 22 in which decoupling element 8 is preloaded by the placement of preloading element 20 relative to fastening body 5, a non-linear spring characteristic may be predefined. By the preloading, a starting point is then set, so to speak, on this non-linear spring characteristic. Such non-linear spring characteristics may also be predefined in other spatial directions by a suitable formation of the decoupling element.

(24) The present invention is not limited to the exemplary embodiments described.