EP2469069A1

EP2469069A1 - Dampening Element for an Injection Valve

Info

Publication number: EP2469069A1
Application number: EP10197076A
Authority: EP
Inventors: Andrea Puccini; Cristiano Mannucci
Original assignee: Continental Automotive GmbH
Current assignee: Continental Automotive GmbH
Priority date: 2010-12-27
Filing date: 2010-12-27
Publication date: 2012-06-27

Abstract

A dampening element (D) for an injection valve (I) is of a washer-like, substantially annular shape and includes a central longitudinal axis (L) . It further includes a plurality of at least three bumps (1) extending in parallel to said central longitudinal axis (L), which are arranged equidistantly to each other.

Description

The invention relates to a dampening element for an injection valve.
Injection valves are in wide spread use, in particular for internal combustion engines where they may be arranged in order to dose the fluid into an intake manifold of the internal combustion engine or directly into the combustion chamber of a cylinder of the internal combustion engine.
In EP 1 262 652 A2 there is disclosed a dampening element to be arranged between an injection valve and the cylinder head of an internal combustion engine. The object thereof is to decrease transitions of noise emissions and vibrations between the injection valve and the cylinder head and so to decrease respective ramifications of said noise emissions. However, it turned out that there occur sticking phenomena between the injection valve and the dampening element, and/or between the dampening element and the cylinder head. And even the noise emissions are still too big. Also absorber rings with spring cushion have been developed. But these did not guarantee constant dimensions over the lifetime of injection valves at different load values applied to the injection valves and the internal combustion engine.
The object of the invention is to create a dampening means for an injection valve which facilitates an increased noise and vibrations dampening function reliable under almost each of a lot of different operating conditions, when being operated in an internal combustion engine.
These objects are achieved by the features of the independent claim. Advantageous embodiments of the invention are given in sub-claims.
The invention is distinguished by a dampening element being of a washer-like, substantially annular shape. It comprises a plurality of at least three bumps, which extend in parallel to a central longitudinal axis of the dampening element. The bumps are arranged at equal distances to each other.
By the arrangement of the bumps the following advantages are achieved:

Due to a reduced contact area between the bumps and the injection valve and/or the cylinder head the sticking phenomena is minimized or even completely avoided.
Due to the reduced contact area between the bumps and the injection valve and/or the cylinder head transfer of noise and vibrations between the injection valve and the cylinder head and vice versa is minimized.

Exemplary embodiments of the invention are explained in the following drawings. These are as follows:

Figures 1 to 5: different embodiments of dampening elements according to the present invention, and
Figure 6: a dampening element in a cylinder head.

Fig. 1 shows a dampening element D. It is of a washer-like, annular shape comprising a central longitudinal axis L, which is orthogonal to two main surfaces 2, 3 of the dampening element D. On a first one (2) of the main surfaces 2, 3 there are arranged three bumps 1. They extend in parallel to the central longitudinal axis L and they are arranged equidistantly to each other. In the embodiment of Fig. 1 the bumps 1 are rib-shaped. This can be seen by making a plurality of cross sections through the bumps at different distances d, d', d" from the central longitudinal axis L: each of the resulting cross sections are in the form of isosceles triangles.
Fig. 6 shows a part of a cylinder head C of an internal combustion engine and a part of an injection valve I, arranged at a bore of the cylinder head C. The injection valve I is separated from the cylinder head C by a dampening element D, which is, in this figure, designed like the dampening element D of the embodiment as shown in Fig. 1. One of the three bumps 1 of the dampening element D of Fig. 1 can be seen in Fig. 6 on the right hand side of the dampening element D, whereas the left hand side of the dampening element D shown in Fig. 6 is free of any of the bumps 1. The remaining bumps 1 of the dampening element D of Fig. 1 cannot be seen in the view of Fig. 6.
Fig. 2 shows another embodiment of the dampening element D. The bumps 1 of this embodiment are achieved by simply bending the dampening element D at a couple of positions, so that three bumps are formed equidistantly to each other.
In the embodiment of Fig. 3 the bumps 1 are of a conical shape, whereby with this embodiment the apex is flattened. However, it is also advantageous not to flatten the apex. In another embodiment, not shown in the drawing, it is advantageous to provide the bumps 1 with a cylinder-like shape.
With the embodiments of Fig. 4 and 5 there are provided two sets of bumps 1 and 1'. Each of the sets of bumps 1, 1' is arranged on a respective one of the two main surfaces 2, 3 of the dampening element D. In Fig. 4 the bumps 1 of the first set of bumps are directly opposed to the bumps 1' of the second set of bumps and vice versa. In Fig. 5, however, the bumps 1 of the first set of bumps are laterally displaced versus the bumps 1' of the second set of bumps, seen in a circumferential direction of the dampening element D. The displacement is half of a circumferential distance d_bump between two adjacent bumps 1 of the first set of bumps (or, which is of the same result: half of a circumferential distance d_bump between two adjacent bumps 1' of the second set of bumps; not shown in Fig. 5). Also the bumps 1 and 1' of the dampening elements D according to the Fig. 4 and 5 may be of a conical or cylindrical shape, as already described herein before along with the embodiments of Fig. 3 and 4, or may have been made by bending the dampening element D like the dampening element D of Fig. 2 (but bent into two opposing directions, parallel to the central longitudinal axis L). Further on, it is also possible to form the shapes of the bumps 1 and 1' of the two sets of bumps in the same manner as is the case with the bumps 1 of the dampening element D shown in Fig. 1.

Claims

Dampening element (D) for an injection valve (I), being of a washer-like, substantially annular shape and including a central longitudinal axis (L), the dampening element (D) including a plurality of at least three bumps (1) extending in parallel to said central longitudinal axis (L) and being arranged equidistantly to each other.
The dampening element (D) of claim 1, wherein said plurality of three bumps (1) is arranged on a first (2) one of two main surfaces (2, 3) of the dampening element (D).
The dampening element (D) of claim 2, wherein there is arranged another plurality of at least three bumps (1') on a second (3) one of said two main surfaces (2, 3) of the dampening element (D) .
The dampening element (D) according to any of claims 1 to 3, wherein cross sections of a respective bump (1; 1'), seen in a plurality of given distances (d, d', d") from the central longitudinal axis (L), are substantially shaped in the form of isosceles triangles.
The dampening element (D) according to any of claims 1 to 3, wherein the bumps (1; 1') having been made by bending the dampening element (D).
The dampening element (D) according to any of claims 1 to 3, wherein the bumps (1; 1') are conically shaped.
The dampening element (D) of claim 6, wherein peaks of the bumps (1; 1') are flattened.
The dampening element (D) according to any of claims 1 to 3, wherein the bumps (1; 1') are cylindrically shaped.
The dampening element (D) according to any of claims 3 to 8, wherein the bumps (1) arranged on the first main surface (2) and the bumps (1') arranged on the second main surface (3) are directly opposed to each other.
The dampening element (D) according to any of claims 3 to 8, wherein the bumps (1) arranged on the first main surface (2) and the bumps (1') arranged on the second main surface (3) are opposed to each other at a lateral displacement between a bump (1) on the first main surface (2) and a nearby arranged bump (1') on the second main surface (3) of half the distance (d_bump) between two adjacent bumps (1; 1') arranged on any of the main surfaces (2; 3).