Chemical apparatus and process disinfecting – deodorizing – preser – Chemical reactor – Waste gas purifier
Reexamination Certificate
1998-06-12
2001-03-13
Tran, Hien (Department: 1764)
Chemical apparatus and process disinfecting, deodorizing, preser
Chemical reactor
Waste gas purifier
C422S180000
Reexamination Certificate
active
06200538
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an exhaust gas system with a catalytic converter through which exhaust gases of an internal combustion engine can flow, for catalytically converting the exhaust gases. The exhaust gas catalytic converter is disposed between two exhaust gas line segments. Each of the exhaust gas line segments forms one line connection with the catalytic converter. The invention relates in particular to motorcycles.
2. Description of the Related Art
German published, non-prosecuted patent application DE 35 43 011 A1 discloses a carrier body for an exhaust gas catalytic converter for converting the exhaust gases of a motor vehicle engine. The carrier body is made up of corrugated and smooth sheet-metal layers that can be coated with a catalyst material. The sheet-metal layers form the walls of a multiplicity of channels through which the exhaust gases can flow inside a tubular housing. German published, non-prosecuted application DE 195 36 853 A1 discloses honeycomb bodies with approximately parallel channels through which the exhaust gases can flow. Among other ways, the honeycomb monoliths may be manufactured by extruding ceramic materials.
An exhaust gas system for an internal combustion engine, in particular an Otto engine of a motor vehicle, is also known from German published, non-prosecuted patent application DE 44 29 878 A1, having an exhaust gas catalytic converter through which exhaust gases of the engine can flow, the exhaust gas catalytic converter being flanged to one exhaust gas line segment on each of its two end faces.
With increasing environmental awareness and ever stricter emissions regulations in many countries of the world, the need has grown to perform catalytic exhaust gas cleaning not only in multi-track motor vehicles but also in motorcycles and in small motors. Small motors are understood here to be motors with a displacement of less than 250 ccm and in particular less than 50 ccm. Such motors are used especially in lawnmowers, edgers, power trimmers, power saws and chain saws, portable generators, small motor bikes, and similar equipment in vehicles. The costs for furnishing an exhaust gas catalytic converter must be in appropriate proportion to the total manufacturing cost for a device or vehicle. Low expense for materials and time is therefore important in retrofitting exhaust gas catalytic converters.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide an exhaust gas system, which overcomes the above-mentioned disadvantages of the prior art devices and methods of this general type and wherein the exhaust gas catalytic converter is integrated into the exhaust gas system in a simple way and in which the exhaust gas system is to be especially suitable for retrofitting exhaust gas catalytic converters in motorcycles.
With the foregoing and other objects in view there is provided, in accordance with the invention, an exhaust gas system, comprising:
an exhaust gas catalytic converter for catalytically cleaning exhaust gases of an internal combustion engine, the catalytic converter having stop faces formed thereon;
two exhaust gas line segments each forming a respective line connection with the catalytic converter on respective sides thereof and contacting the stop faces; and
at least one bracing element engaging at least one of the exhaust gas line segments and bracing the catalytic converter between the exhaust gas line segments.
In accordance with an added feature of the invention, the catalytic converter includes a housing, and the at least one bracing element is one of two bracing elements bracing each of the exhaust gas line segments to the catalytic converter housing.
In other words, the catalytic converter is disposed between two exhaust gas line segments, each forming one line connection with the catalytic converter and each contacting a stop face of the exhaust gas catalytic converter. The exhaust gas system has at least one bracing element, which engages at least one of the exhaust gas line segments and with which the exhaust gas catalytic converter is braced by at least one exhaust gas line segments. One advantage of the exhaust gas system of the invention is that the exhaust gas catalytic converter can be integrated into the exhaust gas system at little expense in terms of time and labor.
For instance, the exhaust gas catalytic converter can be retroactively integrated into the exhaust gas system in a simple way by cutting apart the exhaust gas system at a point and inserting the exhaust gas catalytic converter at that point in such a way that the two exhaust gas line segments, separated from one another, come to rest each on one stop face of the exhaust gas catalytic converter. The catalytic converter is then braced between the exhaust gas line segments with at least one bracing element.
In accordance with an added feature of the invention, the bracing element is an element of elastically variable length subjected to a tensile strain, such as, for instance, a helical spring.
With the invention it is possible to use one short bracing element at the transitions from the exhaust gas catalytic converter to each of the two exhaust gas line segments. Short bracing elements enable especially stable fastening.
In accordance with an additional feature of the invention, one or both of the exhaust gas line segments has an eyelet member formed thereon, and the bracing element is connected to the one or both exhaust gas line segments via the eyelet member. The eyelet may for instance be welded to the exhaust gas line segment. Such a connection can be made simply and inexpensively.
In motor vehicles, for instance, adequate stability of the line connections must be assured. For this reason, and also for the sake of ease in manufacture, there is provided in accordance with again a further feature of the invention, a housing of the catalytic converter, in which on at least one end face of the housing, the housing and a portion of the respective exhaust gas line segment are telescoped inside one another along a connecting region extending crosswise to the circumferential direction. The term “circumferential direction” means the circumferential direction of the housing on the respective end face. In one feature, the exhaust gas system has one of the connecting regions on both of the end faces, and the housing is encompassed on both ends by the exhaust gas line segment. In an alternative embodiment, again with one of the connecting regions on each of the two end faces, on one end face, the housing encompasses the exhaust gas line segment, and on the other end face, the exhaust gas line segment encompasses the housing. Preferably, the first end face is located upstream of the exhaust gas catalytic converter. In this way, any narrow gap between the housing and the respective exhaust gas line segment does not experience a direct oncoming flow, so that good sealing of the line connections is attainable.
In accordance with again an added feature of the invention, the housing has a substantially radial protrusion formed thereon, the protrusion defining the stop face. Preferably, the radial protrusion is a circumferential bead formed around the housing. By means of the at least one bracing element it is assured that the exhaust gas line segments will rest on the respective stop face even under conditions of a thermally dictated change in length of the exhaust gas catalytic converter and/or of the exhaust gas line segments. A bead lends strength to the housing and can be made quickly, for instance with the aid of a pressing tool.
In accordance with a concomitant feature of the invention, the exhaust gas catalytic converter has a reaction region with catalytically active material, the reaction region having a length of less than 15 cm extending in a flow direction. The length of the reaction region, in the preferred embodiment, has a length of approximately 10 cm.
Particularly in retrofitting an exhaust gas catalytic converter, there is often little space available for the exhaust
Bruck Rolf
Diewald Robert
Emitec Gesellschaft fuer Emissions-technologie mbH
Greenberg Laurence A.
Lerner Herbert L.
Stemer Werner H.
Tran Hien
LandOfFree
Exhaust gas system suitable for retrofitting exhaust gas... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Exhaust gas system suitable for retrofitting exhaust gas..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Exhaust gas system suitable for retrofitting exhaust gas... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2483033