| (57) A process for producing a valve-and-lid assembly consisting essentially of a lid
and a valve body, comprises the steps of
(A) producing, in finished condition, the said lid with a collar portion having a
shoulder or a rim about a central opening,
(B) producing separately, in finished condition, the said valve body having an upper
body portion preferably bearing a dowel portion, and on the latter a valve stem bearing
at its free end a valve head of enlarged diameter,
(C) mounting the valve body on the mandrel of a piston movable in a pressure cylinder
aligned with the central axis of the valve-and-lid assembly, or placing it loosely
in said collar portion above said central opening,
(D) striking the mandrel with sufficient force, e.g. preferably 15 to 25 kilopond,
to drive the same together with the valve body abruptly through the collar portion
of the lid and to pass the valve head out of the said central opening with stretching
or bending the valve stem or an adjacent part of the valve body, so that, upon withdrawel
of the mandrel, a rearward face of the valve head sealingly engages the shoulder or
rim about the central opening
The self-closing valve-and-lid assembly which can be produced by this process is adapted
for closing the open top end of the interior of a container fillable with pressurized
product and comprises a lid having a dome part and a collar portion on the latter,
as well as a valve body mounted in the hollow interior of the dome part and being
of elastically flexible material. The valve body has a head bearing an annular contact
zone which sealingly engages a similar contact zone on an annular indentation or inner
annular shoulder of the dome part.
One of the annular contact zones of the inner wall surface of the dome part and of
the valve head is located in a conically tapered surface on one of the two last-mentioned
parts with the central assembly axis as cone axis, and the other annular contact zone
is a substantially circular edge on the other one of the two last-mentioned parts,
opposite the said conically tapered surface.
|
|
