FR2807352A1 - EXHAUST VOLUME COMPRISING A THROUGH TUBE AND METHOD FOR THE PRODUCTION THEREOF - Google Patents

Abstract

The exhaust volume comprises a transverse wall (14) provided with an orifice (18) and a tube (16) passing through said wall through said orifice (18). The wall (14) and the tube (16) are connected to each other. The wall (14) has, around the orifice (18), a barrel (20) obtained by drawing the material from the wall (14). The barrel (20) and the tube (16) are crimped along their periphery in a transverse plane of the barrel (20) .Application to a motor vehicle exhaust silencer.

Description

The present invention relates to an exhaust volume, of the type comprising

  a transverse wall provided with an orifice and a through tube

  said wall through said orifice, the wall and the tube being linked to each other.

  Such exhaust volumes in particular constitute silen-

  exhaust skies reducing noise pollution from traffic

  exhaust gases, or even enclosures in which are

  catalytic purification elements or particulate filters.

  The exhaust volumes generally have a side wall

  substantially cylindrical track closed at each end by a transverse end wall. The transverse wall is for example crimped at its

periphery to the side wall.

  In order to evacuate the exhaust gases or to introduce them into the enclosure delimited by the exhaust volume, the transverse end walls are traversed by conduits for conveying the gases.

exhaust.

  So, for example, the end wall is crossed by a tube

  exhaust extending mainly inside the exhaust volume

  pement and extending beyond the wall outside the volume. A

  the outlet cannula is sometimes crimped at the end of the tube to extend

  vantage this outside the exhaust volume.

  In order to ensure the substantially tight connection of the tube and the wall, it is known to use a connecting sleeve surrounding the tube in

  the region of the transverse wall. This sleeve is tightened on the tube and it pre-

  feels, on either side of the wall, flanges between which is

  tightened the wall. These flanges are formed by deformation of the sleeve,

  and in particular by axial crushing thereof in order to form peri-folds

  spheres delimiting flanges extending radially outwards and

enclosing the transverse wall.

  In addition, when a cannula is used to extend the tube passing through the wall, the latter is crimped between the outer end of the tube and the

  part of the sleeve extending externally.

  Although this assembly solution works satisfactorily

  health, the manufacturing cost of the exhaust volume is relatively high.

  due to the presence of the connecting sleeve attached around the tube and the assembly operation required between the transverse wall and this sleeve. The object of the invention is to propose an exhaust volume, the manufacturing cost of which is reduced, in particular as regards the connection.

  between a transverse wall and a tube passing through it.

  To this end, the invention relates to an exhaust volume, of the aforementioned type, characterized in that the wall has, around the orifice, a barrel obtained by drawing the material from the wall, and in that the barrel and the tube

  are crimped along their periphery in a transverse plane of the barrel.

  According to particular embodiments, the volume of escape-

  one or more of the following characteristics:

  - the crimping of the barrel and the tube is formed by a concentric constriction

  barrel and tube stick; - The transverse wall is an end wall, and the barrel extends outside the enclosure defined by the exhaust volume;

  - it includes a cannula extending the tube on the side of the trans wall

  versal o emerges the barrel, and the cannula and the barrel are crimped according to the plane of crimping of the tube and the barrel; - the cannula is crimped outside the barrel

  - the cannula present laterally in the crimping plane of the case

  null and barrel, two diametrically opposite folds .; and

  - the tube and the cannula are crimped with each other in a transverse plane

  transverse to the tube, which transverse plane is offset along the length of the tube

  with respect to the plane of crimping of the tube and the barrel.

  Furthermore, the subject of the invention is a method of manufacturing a

  exhaust lume as defined above, characterized in that it comprises

  carries the steps of: a) forming a transverse wall provided with an orifice; b) stretching the material of the transverse wall around said orifice to form a barrel; c) insert a tube into the barrel; and

d) crimp the barrel and the tube.

  According to the invention, the manufacturing process can also include the steps: - of placing a cannula extending the tube, and of crimping

  cannula and barrel, and the crimping of the cannula and barrel is done

  dried simultaneously with the crimping of the barrel and the tube; and - placing a cannula extending the tube and crimping the cannula and the tube, and crimping the cannula and the tube is carried out

  simultaneously with the crimping of the barrel and the tube.

  The invention will be better understood on reading the description which will

  follow, given only as an example and made with reference to the

  sins, in which: - Figure 1 is a partial view in longitudinal section of a volume

  exhaust according to the invention on which a manufacturing tool is used

partially represented; and

  - Figure 2 is a sectional view taken along line 11-11 of Figure

  gure 1 showing the connection of the tube to the transverse wall.

  In Figure 1 is shown an end portion of an exhaust silencer 10 made entirely of metal. The silencer 10 has a substantially cylindrical side wall 12 closed at one end by

  a transverse wall 14. The latter is commonly designated by the ex-

  "end cup" pressure. The side wall 10 is connected to its end

  miter at the periphery of the end wall 14. These are joined to each other by a crimp 16 obtained by concentric winding of

ends of the sheets.

  The wall 14 is crossed by an outlet tube 16. The tube 16 com-

  carries an internal section 16A extending inside the enclosure denoted 17

  delimited by the exhaust silencer and an external section 16B extended

  giant tube outside of this enclosure. The section 16B has a length

  between 10 and 40 mm and for example equal to about 27 mm.

  The tube 16 passes through the transverse wall 14 through an opening

  ture 18 substantially circular. The opening 18 is delimited by a barrel 20

  obtained by stretching outwards the material constituting the transverse wall

  dirty 14 in the border region of the opening 18. The barrel 20 has a long

  range between 10 and 30 mm and preferably of the order of 20 mm.

  In addition, a cannula 22 is secured to the tube 16 and to the barrel 20. The

  cannula 22 extends completely outside the enclosure 17 and extends axially

  Lement the tube 16. It surrounds the barrel 20 over most of its length. The tube 16 has an end section denoted 16C and

  extending on either side of the transverse wall 14 a very small diameter

  slightly larger than the diameter of its running part. Furthermore, and as

  illustrated in Figures 1 and 2, the tube 16, the barrel 20 and the end of the housing

  outlet 22 are crimped together to ensure their mechanical connection.

  This crimping is carried out by shrinking the three concentric surfaces. It is

  made in a transverse plane of the barrel 20 designated by crimping plane

senior sage.

  The constriction noted 23 leads to a centripetal peripheral deformation of the tube 16, of the barrel 20 and of the end of the cannula 22. Thus, concentric peripheral channels, resulting from an inward curving, are

  created around these three elements. These channels have a sensitive section-

in the shape of an arc of a circle.

  In addition, the cannula 22 has, along its length, two diametrically opposite folds 24 resulting from the creep of the material forming the cannula

when shrinking.

  The cannula 22 and the tube 16 are also crimped one on the other following

  in front of another constriction 26 extending in a plane parallel to the setting plane

  main sage of the tube, barrel and cannula. The two setting plans

  wise are axially spaced by an interval, having a length for example

ple equal to 12 mm.

  The crimp 26 is adapted to ensure centripetal deformation of the end of the tube 16 and the outlet cannula 22. This constriction thus forms, at the periphery of the tube and the cannula, concentric channels resulting from a curvature towards the inside. These channels have an arcuate section

of circle.

  For the manufacture of such an exhaust volume, a stretching of the transverse wall 14 is first carried out around the opening 18 to form the barrel 22, the latter being initially substantially cylindrical. The tube 16 is then introduced through the opening 18. The outlet cannula 22 is finally

  fitted around the tube 16 and the barrel 20.

  For crimping, two jaws each delimiting a semi-cylindrical impression and each comprising two projections 32, 34 semi

  axially spaced cylindrical cylinders are applied around the cannula 22.

  The projections 32 and 34 have a section substantially in an arc.

  The bringing together of the two jaws towards one another in a diametrical direction of the barrel causes a constriction of the tube, of the barrel and of

  the cannula, thus leading to the arrangement shown in Figures 1 and 2.

  Thus, the constrictions 23 and 26 are produced during the same crimping step. It is understood that, with the arrangement described here, the presence of the barrel obtained by stretching the material forming the transverse wall 14, allows

  to ensure the connection of the tube and the transverse wall 14 without it being born

  stop implementing an added sleeve. In addition, the liaison provided

  rée by crimping is reliable and is of a reduced cost of implementation.

  In addition, the tube 16 and the cannula 22 being linked, during the same operation.

  tion, at the barrel 20, the establishment of the outlet cannula 22 is carried out without

  significant additional cost, the same operation ensuring several connections.

  Finally, such a connection between the transverse wall 14 and the tube 16 can be ensured by crimping the tube and a barrel obtained by drawing the

  transverse wall 14, even in the absence of an outlet cannula 22.

Claims (9)

  1.- Exhaust volume comprising a transverse wall (14) provided with an orifice (18) and a tube (16) passing through said wall through said orifice (18), the wall (14) and the tube (16) being linked to each other, characterized in that the wall (14) has, around the orifice (18), a barrel (20) obtained by drawing the material from the wall (14), and in what the barrel (20) and the   tube (16) are crimped along their periphery in a transverse plane of the no (20).   2.- exhaust volume according to claim 1, characterized in that the crimping of the barrel (20) and the tube (16) is formed by a constriction   concentric of the barrel (20) and the tube (16).   3.- exhaust volume according to any one of the claims   previous, characterized in that the transverse wall (14) is a wall   end, and in that the barrel (20) extends outside the enclosure finished by the exhaust volume.   4.- exhaust volume according to any one of the claims   above, characterized in that it comprises a cannula (22) extending the tube (16) on the side of the transverse wall (14) where the barrel (20) emerges, and   in that the cannula (22) and the barrel (20) are crimped along the crimp plane wise from the tube (16) and the barrel (20).   5.- exhaust volume according to claim 4, characterized in that   that the cannula (22) is crimped outside the barrel (20).   6.- exhaust volume according to claim 4 or 5, characterized in that the cannula (22) has laterally in the crimping plane of   the cannula (22) and the barrel (20), two diametrically opposite folds (24).   7.- exhaust volume according to any one of claims   4 to 6, characterized in that the tube (16) and the cannula (22) are crimped with each other in a plane transverse to the tube (16), which transverse plane is offset along the length of the tube (16 ) in relation to the crimping plane tube (16) and barrel (20).   8.- Method of manufacturing an exhaust volume according to one   any one of the preceding claims, characterized in that it comprises   carries the steps of a) forming a transverse wall provided with an orifice; b) stretching the material of the transverse wall around said orifice to form a barrel (20); c) inserting a tube (16) into the barrel (20); and d) crimping the barrel (20) and the tube (16). 9.- Method according to claim 8 for manufacturing a volume   exhaust according to any one of claims 4 to 7, characterized   in that it further comprises a step of placing a cannula (22) extending the tube (16), and a step of crimping the cannula (22) and the barrel (20),   and in that the crimping of the cannula (22) and of the barrel (20) is carried out if-   simultaneously with the crimping of the barrel (20) and the tube (16).   O.- Method according to claim 8 or 9 for manufacturing an exhaust volume according to claim 7, characterized in that it further comprises a step of placing a cannula (22) extending the tube (16) and a step of crimping the cannula (22) and the tube (16),   and in that the crimping of the cannula (22) and of the tube (16) is carried out if-   simultaneously with the crimping of the barrel (20) and the tube (16).