Note: Descriptions are shown in the official language in which they were submitted.
~LZ~3~
~IB~ON BLOWN GLASS ARTICLE
BACKGROUND THE INVENTION
Ribbon blown glass envelopes have been
traditionally formed on a ribbon machine with two~part
molts having a partible construction and which rotate
S while encircling a hollow molten glass blank. Said
conventional glass molds have been`generally provided
with a paste coating ox the central mold cavity along
with vent openings to Eorm a steam cushion against
which the glass envelope is blown wtlile said mold
0 halves are rotating. Although the bulb portion ox a
glass envelope blown in the conventlonal manner has
included cylindrical as well conical and spherical
shapes, all of tllese shapes terminated at the closed
end of the bulb portion in a spherical contour
preventing the blown article from physically supporting
itself. Accordingly, such limitation has retarded any
wider utilizatioll of conventional ribbon blown glass
envelopes in a variety of end product applications
including liquid containers and even lamp glass
onvelopes requiring a relatively flat face portion to
serve as a liens member in the lamps.
The present invention relates to novel means
whereby glass articles of various types are blown on a
ribbon machine in a novel mold construction which
shapes the closed end of the glass~envelope tO provide
a self-supporting base contour. More particularly,
:
,
~-~4232~ `
.
-- 2
said novel mold construction includes three basic parts
which cooperate in forming a bulb shape terminating in
a flattened contour sufficient to permit the glass
envelope to be self supporting, that is to stand alone
without additional physical suppoit. The basic mold
design of the present invention includes a pair of
cooperative partible halves forming the sides of the
blown glass envelope in a central cavity and which
further includes a separate base part located at the
lower end ox said cavity to shape the closed end of
said blown glass envelope into the desired
self-supporting contour, said base part of the mold
being provided with reciprocal motion in a vertical
direction.
Accordingly, an important object of thy
pr~sont invention is to provide a ribboll blown glass
envelope having assorted shapes for various end product
application wherein the bulb portion of said envelope
terminates in a self~supporting contour.
Another lmportant object of the present
invention is to provide ribbon blown glass envelopes
having either curved or planar sides together with an
integral self-supporting base contour which can also be
planar or curved in shape.
Still another important object of the present
invention is to provide an improved method for
manufacture of said novel glass envelope on a ribbon
machine by means of a novel mold design.
SUMMARY OF THE INVENTION
In accordance with the present invention,
there is provided a ribbon formed glass envelope having
a cylindrical neck portion terminating at one end in a
closed bulb portion of larger cross-sectional
dimensions and which includes a self-supporting base
contour. In various preferred embodiments, the glass
.
23~
envelope is blown from either molten hard or soft glass
compositions of a conventional type and with said
self-supporting base end being either a flat plane or
defined by the intersection of two or more 1at
planes. Alternately, the self-supporting base contour
of said blown glass envelope can be a curved surface
having either a convex or concave shape with respect to
the sides of said glass envelope but of such limited
curvature that said envelope physically supports itselÇ
when resting on its base end. The side of the present
blown glass envelope can also be planar or curve in
shape with the planar sided glass envelopes requiring
that the mold halves understandably not rotate while
the glass envelope is being formed.
The basic method of the present invention
continuously forms the blown glass envelope frocl a
molten ribbon of glass supported on a moving conveyor
by means of:
(a) blowing a portion of the glass prom
said molten ribbon into the central cavity
o a multi-part mold, said mold including
a pair o cooperative halves formillg the
sides of said blown glass el~velope by
encircling the molten glass while being
blown and which mold Eurther includes a
separate base part located at the lower
end of said cavity to form the self-
supporting terminal end of said blown
glass envelope, said base part of the
mold being provided with reciprocal
motion in a vertical direction,
(b) having the base part of said mold
move upwardly and remain in an upward
position while the glass envelope is
being blown but then moved dowllwardly and
, ..
I: ,
: ,
- 4 -
release the lamp glass envelope before
the mold halves are opened,
(c) opening the told halves to release
che sides of the solidifled blown glass
envelope, and
(d) severing the blown glass envelope
from the moving glass ribbon.
In a preferred form of said method for manufacture of a
glass envelope having symmetrical curved sides, the
mold halves include means to form a steafil cusllion
against which the glass envelope is blown, such as the
already known ventilated paste type mold, and with said
mold halves being rotated during formation of the glass
envelope. In said preferred method, the base part of
the mold also includes vent openings to help ventilate
the central cavity but generally does not require a
paste coating to form a suitable self~supporting base
end or the blown glass envelope.
In thy preferred method oÇ orming glass
envelopes having planar sides according to the present
invention, both mold halves and the base part remains
stationary with respect to each other while the glass
envelope is being blown. The mold parts are also
entirely devoid of a paste coating or ventilation means
despite providing a self-supporting base end on the
blown glass envelope which can either be planar or
curved. It is further possible to provide blown glass
envelopes according to said preferred embodiment from
conventional hard glass compositions as well as soft
glass compositions although soft glass would generally
be selected for most end product applications involving
ordinary temperature service.
BRIEF DESCRIPTION OF THE DRAWING
Flgure l illustrates a fragmentary side
~35 elevatiol~ view of an exemplary glass ribbon machine
:
;.; , : ,
, , :
embodying the present invention.
Figure 2 is a perspective view illustrating a
simplified nlold design according to the present
invention.
Figure 3 is a perspective view illustrating
one type glass envelope formed in accordance Witll the
present invention.
Figure 4 is a perspective view illustrating a
different type glass envelope formed according to the
present invention.
DESCRrPTIO~I OF THE PREFERRED EMBODI~:ENTS
referring to Figure l, there is partially
depicted a conventional hot ribbon machine 10 which
forms the presently improved glass envelope 12 from a
molten ribbon of glass 14 that is being carried on a
moving conveyor having interconnected orifice plates
16. The molten glass is blown downwardly by blowheads
18 into thy central cavity portions of glass molds 20
constructed in accordance with the present invention.
I 20 The mold halves Z2 are closed while a cylindrically
I shaped glass envelope ls bein8 blown whlle the separate
I base portion 24 ox each mold is moved upwardly and
retained in the upward position during this step oE the
manufacturing process. downward movement of said base
part in the molds is automatically carried out on said
ribbon machine by conventional means after the molten
glass has solified in the mold cavities as a necessary
step before said mold halves are opened. Rotation of
the mold halves 22 wllich is carried out when the glass
envelopes are formed in this manner as well as severing
the blown glass envelopes from the moving glass ribbon
after the mold halves have been opened are all carried
out in the customary wanner now being utilized in
ribbon machine manufactùre.
A simplified mold construction 26
': :
.
incorporating the essential structural features
required to form tlle above described blown glass
article is depicted in Figure 2. Specifically, a pair
of mold halves 28 and 30 cooperate to form the side
portions of the cylindrical blown glass envelope in a
central cavity 32 which terminates in a separate flat
base part 34 of circular contour 35. Vent openings 36
are provided on the upper bare metal surface of said
flat base part as an optional means to help ventilate
the mold cavity. Said base part 34 is also provided
with reciprocal motion in a vertical direction by means
of being mounted on the bearing surface 38 and with
said upward motion being limited by physical contact
with a rim surface 40 machined at the lower end of the
lS cooperating mold halves. In said mold construction,
the cooperating mold halves are rotated in the
customary manner to Norm the cylindrical glass envelope
and with said mold halves further having vent openings
42 along with a paste coating 44 being applied to the
inner surface of the cental mold cavity.
In Figure 3 there is depicted a perspectiYe
view o a representative lass envelope formed as
above described and which can be utilized as a liquid
container. Said blown glass article 46 includes a
cylindrical neck portion 48 terminating at one end in a
bulb portion of larger cross sectional dimensions 50
which includes a self-supporting closed end 52 of
planar configuration 54. As can be observed, the sides
and base portions of the blown glass article are all of
relatively uniformly thickness as well as devoid of any
physical mold seams.
Figure 4 is a perspective view of a different
blown glass article 60 having a straight sided
configuration 62 formed by intersection of a pair of
opposing and parallel flat planes 64 and 66. Said
. , i I; . , . .. , ::; :
- 7 -
glass article further includes a cylindrical neck
portion 70 terminating in a straight sided bulb portion
of larger cross sectional dimensions and with the bulb
portion of said glass article ending in a
self-supporting base 72 of convex curvature 74. As can
be observed from the,drawing, however, a visible mold
seam 76 is produced in a said glass article due to non
rotation of lie mold halves during the glass forming
operation.
While preferred embodiments of the present
invention along with improved methods for manufacturing
said embodiments have been shown and described, various
other embodiments along with modifications in the
described method of manufacture w,ill become apparent to
. . lS persons skilled in the art without departing from the
true spirit and scope of the present invention. or
example, it would be apparent from the foregoing
description chat various combinations o planar and
curved sides can be employad for the bulb portion of
the blown gla9s envelope as well as in the
self-supporting base end o said envelope.,
Accordingly, the scope of the present invention is
limited only to the following claims:'
.
; . :
. . ,
