Exhaust component manufacturing device and process

Abstract

A machine comprises a tool for pre-positioning of a body of an exhaust component and a fitting tool having a passage converging from a large opening to a small opening. An actuator device is configured to push the body along a main axis of the machine toward a cover of the exhaust component through the converging passage.

1 . A machine for manufacturing an exhaust component comprising:
 a body including a tubular enclosure, the tubular enclosure having an enclosure thickness of less than 0.9 mm, the tubular enclosure having a first end having a first end perimeter and a first central end axis;   a cover having a cover thickness smaller than 1.2 mm, the cover having a central wall extending by a tubular edge, the tubular edge having an edge perimeter comprised between the first end perimeter and the first end perimeter minus 2 mm and having a central edge axis;   the machine comprising:   a seat for receiving the cover in a determined cover position in which the central edge axis is substantially aligned with a main axis of the machine;   a pre-positioning tool of the body, configured to pre-position the body relative to the cover in a starting position in which the first central end axis forms, with the central edge axis, an angle smaller than 20°;   a fitting tool, interposed between the seat and the pre-positioning tool along the main axis, the fitting tool having a passage converging from a large opening to a small opening, the first end of the tubular enclosure emerging in the large opening in the starting position, the small opening emerging in the tubular edge in the cover position;   an actuator device, configured to push the body along the main axis toward the cover through the converging passage, the converging passage being configured to deform the first end of the tubular enclosure.   
     
     
         2 . The machine according to  claim 1 , wherein the machine includes a plurality of sectors movable selectively between a radially inner position in which the plurality of sectors together define the converging passage, and a radially outer position allowing the insertion of the cover into the seat. 
     
     
         3 . The machine according to  claim 2 , wherein the plurality of sectors in the radially inner position also define the pre-positioning tool. 
     
     
         4 . The machine according to  claim 2 , wherein the plurality of sectors form a reversible locking, configured to selectively block the cover relative to the seat in the cover position. 
     
     
         5 . The machine according to the  claim 1 , wherein the fitting tool comprises a wider passage extending the converging passage toward the seat along the main axis, the wider passage having a larger section than the small opening and receiving a free edge of the tubular edge in the cover position. 
     
     
         6 . The machine according to the  claim 1 , wherein the machine comprises at least one adjustable stop of the actuator device arranged to adjust a separation along the main axis between a reference point of the cover and a reference point of the body. 
     
     
         7 . The machine according to the  claim 1 , wherein the actuator device comprises a guide head arranged to push the body, an actuator configured to move the guide head along the main axis, and a linear guide guiding the guide head along the main axis. 
     
     
         8 . The machine according to  claim 7 , wherein the guide head comprises at least one cam member, provided to cooperate with a cam follower formed on the body to place said body along a predetermined orientation around the main axis relative to the cover. 
     
     
         9 . The machine according to  claim 7 , wherein the guide head comprises a shape provided to inwardly receive a second end of the tubular enclosure and guarantee the alignment of the tubular enclosure with the cover. 
     
     
         10 . The machine according to  claim 1 , wherein the pre-positioning tool includes an inner passage with a shape conjugated to that of the first end. 
     
     
         11 . A method for manufacturing an exhaust component, the method comprising the following steps:
 obtaining a tubular segment including a tubular enclosure, the tubular enclosure having an enclosure thickness of less than 0.9 mm, the tubular enclosure having a first end having a first end perimeter and a first central end axis;   obtaining a cover, having a cover thickness smaller than 1.2 mm, the cover having a central wall extending by a tubular edge, the tubular edge having an edge perimeter comprised between the first end perimeter and the first end perimeter minus 2 mm and having a central edge axis;   pre-positioning the tubular segment relative to the cover in a starting position in which the first central end axis forms, with the central edge axis, an angle smaller than 20°;   introducing the first end into the tubular edge by moving the tubular segment toward the cover along a main axis, the first end passing through a converging passage from a large opening to a small opening emerging in the tubular edge.   
     
     
         12 . The method according to  claim 11 , wherein the tubular edge is welded on the first end by a MAG method, preferably with low energy. 
     
     
         13 . The method according to  claim 11 , wherein the tubular enclosure has a second end having a second end perimeter and a second central end axis;
 the method further comprising the following steps:
 obtaining another cover, having another cover thickness smaller than 1.2 mm, the other cover having another central wall extending by another tubular edge, the other tubular edge having another edge perimeter comprised between the second end perimeter and the second end perimeter minus 2 mm and having another central edge axis; 
 pre-positioning a subassembly formed by the tubular segment and the cover fastened to the tubular segment relative to the other cover in a starting position in which the second central end axis forms, with the other central edge axis, an angle smaller than 20°; 
 introducing the second end into the other tubular edge by moving the subassembly toward the other cover along a main axis, the second end passing through a passage converging from a large opening to a small opening emerging in the other tubular edge. 
   
     
     
         14 . The method according to  claim 13 , wherein the method comprises a step for orienting the cover around the main axis relative to the other cover, before the step for introducing the second end. 
     
     
         15 . The method according to  claim 13 , wherein
 the cover includes an exhaust gas outlet outside an exhaust volume,   during the step for introducing the first end, the movement of the tubular segment toward the cover is stopped by a stop arranged so that the second end of the tubular enclosure has a predetermined separation along the main axis relative to a reference point of the cover when the stop is reached;   the other cover includes an exhaust gas inlet in the exhaust volume,   during the step for introducing the second end, the movement of the subassembly toward the other cover is stopped by a stop arranged so that the reference point of the cover has a predetermined separation along the main axis relative to another reference point of the other cover when the stop is reached.   
     
     
         16 . The method according to  claim 15 , wherein the tubular segment includes an exhaust gas purification member housed in the tubular enclosure, the exhaust gas purification member having an exhaust gas inlet face having a predetermined separation relative to the second end of the tubular enclosure along a central axis of the tubular segment. 
     
     
         17 . The method according to  claim 11 , wherein the cover includes an exhaust gas inlet in the exhaust component, the movement of the tubular segment toward the cover being stopped by a stop arranged so that a second end of the tubular enclosure has a predetermined separation along the main axis relative to a reference point of the cover when the stop is reached. 
     
     
         18 . The method according to  claim 17 , wherein the tubular segment includes an exhaust gas purification member housed in the tubular enclosure, the exhaust gas purification member having an exhaust gas inlet face having a predetermined separation relative to the second end of the tubular enclosure along a central axis of the tubular segment. 
     
     
         19 . The method according to  claim 15 , wherein the tubular enclosure has, along the first central end axis, a length equal to a nominal length plus an allowance comprised in an interval [−ΔL1+ΔL2], the stop stopping the movement of the tubular segment toward the cover being arranged such that a tubular enclosure of nominal length has its first end engaged in the tubular edge over a predetermined covering length when the stop is reached, the covering length being chosen such that R−ΔL1 is comprised in an interval [2 mm, 5 mm]. 
     
     
         20 . The method according to  claim 19 , wherein the tubular edge has a predetermined height along the axis of the edge, chosen such that R+ΔL2<H0. 
     
     
         21 . The method according to  claim 19 , wherein the tubular enclosure has a central segment having a section smaller than the section of the first end and connected to the first end by a step, the first end having, up to the step along the first central end axis, a length comprised in the interval [R+ΔL2+3 mm, R+ΔL2+7 mm].