This invention relates to a leakage connection for connecting a leakage pipe to a fuel injector.
Such a leakage connection is known from EP 0 886 065, in which case for the injection system to function, one of the features required for each injector is a connection for returning a part of the diesel fuel that was fed to the injector to the tank of the vehicle. This leakage connection should be inexpensive to manufacture and easy to install and dismantle, but it should not be able to become disconnected by itself. According to EP 0 886 065, a wire clamp is taken as the basis to start from that requires a matching groove at the leakage connection. During installation, the leakage insert is first of all inserted in the leakage bore in the injector. The wire clamp is subsequently pressed from the side into the groove on the leakage insert in order to secure the leakage connection. As a result, the wire clamp is then accommodated in a slot-type guide that forms part of the injector housing. The leakage housing is dismantled in the opposite sequence.
The same applies to the leakage connection according to DE 199 40 387 in which case the wire clamp is kept in an opening at the connection piece with a first straight arm. With a second curved arm, a clamp connection with the insert of the connection nipple is made in a final stage of installation via a sufficiently deep recess in the bore on the connection piece.
The object of the invention is to provide a leakage connection for connecting a leakage pipe to a fuel injector that is inexpensive to manufacture and that can be easily and reliably installed.
According to the invention, this object can be achieved by a leakage connection for connecting a leakage pipe to a connection piece of a fuel injector, comprising a connection nipple that is guided with an insert in a bore of the connection piece, and a flexural elastic securing device that retains the connection nipple in the bore, wherein the securing device is formed by a snap ring that can be inserted in a nipple groove configured on the periphery of the insert, wherein a bore groove is configured in the inner peripheral wall of the bore corresponding to the nipple groove, wherein in the mounted state of the leakage connection, the snap ring, with a part of its wall thickness, lies in the bore groove and with the rest of its wall thickness in the nipple groove, thereby preventing the leakage connection from being unintentionally withdrawn, and wherein a depth of the nipple groove is at least the same size as a diameter of the material of the snap ring.
The bore groove may have a withdrawal bevel on the periphery in the demounting direction. The connection nipple and the bore may have corresponding stops that limit the insertion path of the insert in the bore. The corresponding stops can be arranged at an angle to the longitudinal axis of the connection nipple. Below the corresponding stops, a second pair of corresponding stops can be arranged on the connection nipple or the bore, wherein the stops of the second pair are arranged at an angle to the longitudinal axis of the connection nipple and wherein an O-ring groove with an O-ring is arranged between the two stop pairs.
According to the invention, instead of the wire clamp, the leakage connection provides for a simple ring of spring steel particularly in the form of a snap ring. Thus, the snap ring is premounted on the leakage connection in a groove and is slotted on one side. The size of the slot must be dimensioned in such a way that when the leakage connection is installed, it must be possible to compress the snap ring to such an extent that it fits through the bore in the injector. At the leakage housing or the connection nipple, the shape of the groove provides a corresponding free space for the deformation of the snap ring. In the lower area of the leakage bore there is a corresponding groove in which the snap ring can again slacken. The leakage connection can then only be dismantled by overcoming the initial stressing forces of the snap ring. The peak of the installation and dismantling forces can be influenced by the rigidity of the spring of the snap ring as well as by mounting bevels on the leakage bore. Installation and dismantling is a simple matter of inserting or withdrawing. An additional advantage of the invention is the low production cost of the injector housing by omitting the guide for the wire clamp and the simple design of the snap ring compared with the wire clamp.
An embodiment of the leakage connection according to the invention is described below; the accompanying drawings are as follows:
According to
According to
Number | Date | Country | Kind |
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10203600.4 | Jan 2002 | DE | national |
This application is a continuation of copending International Application No. PCT/DE03/00225 filed Jan. 28, 2003 which designates the United States, and claims priority to German application no. 102 03 600.4 filed Jan. 30, 2002.
Number | Date | Country | |
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Parent | PCT/DE03/00225 | Jan 2003 | US |
Child | 10902248 | Jul 2004 | US |