[0001] The present invention relates to a silencer having a considerable utility and ease
of use because of the unwelded connection of the caps and the pipes to the ends of
said silencer.
[0002] The silencers presently available on the market have the considerable drawback of
requiring weldings for joining the various components and it is known that welding
is a time-consuming, troublesome, expensive and polluting process, requiring also
skilled and qualified operators. The quality of the weld affects in a decisive way
the performance and operative life of the silencer, and in view of the steadily increasing
shortage of skilled qualified welders, it is more and more difficult to produce silencers
of a good quality and long-lasting.
[0003] Furthermore, welding has the intrinsic drawback of altering the material of the workpiece
and of its coating (aluminizing) so that it is necessary to carry out again plating
of the metal at the welding area after the welding operation.
[0004] The present invention removes these drawbacks because it eliminates welding of the
silencer inner pipe to the end caps as well as of the exhaust and tail pipes to the
inner pipe, which is now forming a mass of weld material all around and on the edge
of the cap bore.
[0005] The improved silencer according to the present invention is therefore characterized
by the fact that its inner pipe is fixed to the end caps by seaming, while the incoming
exhaust pipe (from the engine) and the outgoing tail pipe are in turn fixed to the
corresponding ends of the inner pipe also by seaming.
[0006] The advantages obtained with this system are various and considerable, such as the
great reduction of manufacturing cost due to welding elimination, without needing
the specialized staff for it, which can now be replaced by unskilled labor, moreover
doing a light job in a non polluting environment; manufacturing speed and uniform
quality of the product, no more subject to the individual skill of the welders; elimination
of thermal stresses and chemico-physical alterations of the material, which were caused
by the welding process.
[0007] These and other advantages, objects and features of the present invention will be
more apparent from the following detailed description, made with reference to the
sole figure of the accompanying drawing, diagramatically showing the area of connection
of the inner pipe to an end cap of the silencer, as well as of an exhaust pipe to
the end of said inner pipe.
[0008] With reference now to said sole figure of the accompanying drawing, one can see partially
the outer body 1 of the silencer to which the usual closure cap 3 is seamed by means
of a double heading 2.
[0009] The silencer inner pipe 4 is fixed to the cap 3 by seaming, obtained by cold making
with a suitable tool two waves or dimples 5 and 6 between which the edge 7. of the
cap bore is clamped, so as to create the stable, safe and resistant connection of
said elements, by means of pressure and deformation of the two matching surfaces.
[0010] In the same way the exhaust line is fixed at the end of inner pipe 4, protruding
outside the silencer.
[0011] The pipe 8, which can be either the incoming exhaust pipe from the engine exhaust
manifold or the outgoing tail pipe discharging to the atmosphere the exhaust gases,
is inserted into or onto the end of said inner pipe 4 and then with an outer seaming
operation for the two assembled pipes, two corresponding waves or dimples 9 and 10
are formed on them, so as to mutually clamp them in a stable and safe way.
[0012] It is to be understood that the materials used, the equipment and tools used to carry
out the connection of the elements, the number and size of the pipes may be varied
in the wider and greater manner, without departing however from the principles and
the features illustrated and described hereinbefore.
1) Improved silencer, characterized by the fact that its inner pipe (4) is fixed by
seaming to the end caps (3) of the silencer, while the incoming exhaust pipe and/or
the outgoing tail pipe are in turn fixed by seaming to the corresponding ends of said
inner pipe (4).
2) Improved silencer according to Claim 1, characterized by the fact that the inner
pipe (4) gets by cold deformation two waves or dimples (5, 6) between which the edge
(7) of the silencer cap bore is clamped.
3) Improved silencer according to Claim 1, characterized by the fact that the incoming
exhaust pipe and/or the outgoing tail pipe is inserted into or onto the free end of
the silencer inner pipe (4) and then the two assembled pipes get by cold deformation
two corresponding waves or dimples (9, 10) which are mutually clamping them together.
4) Improved silencer according to one or more of the preceding claims, characterized
by the fact that the end cap (3) is seamed to the silencer body (1) by double heading
(2).
