Note: Descriptions are shown in the official language in which they were submitted.
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The present invention relates to apparatus for shift- -
ing the pouring trough of centrifugal casting machines of the
retraction casting type for casting pipe tubes and the like
and, more specifically, tG apparatus for shifting the longi-
tudinal pouring trough of a centrifugal casting machine of the
deLavaud type.
Such apparatus have been well known in the art for
many years and are generally referred to a~ trough shifters.
Due to the environment in which such apparatus must operate,
it is difficult to prevent malfunctions. Generally, trough
shifter apparatus are located ~ust beneath the machine ladle
and the trough chute into which the machine ladle pour~ molten
metal and are usually operated by fluid power devices. Many
tons of iron are poured each day from a transfer ladle into
the machine ladle and then from the machine ladle into the
trough chute. Due to various reasons molten metal is spilled
or splashed in such manner as to cause unusual wear, uneven
movement and occasionally complete failure of the shifter
mechanism. Splash guards and covers have been devised and
offer protection; however, such means prevent access for in-
spection and maintenance. The problem is further aggravated
by the necessity to rake or skim slag from the machine ladle
and the need to pour a liquid refractory on the trough chute.
This refractory is also spilled or splashed in such a manner ;
as to find its way onto the rollers, rails or slidewsys of the
known shifting apparatus. Various scrapers and wipers have
been employed to automatically clean the running surfaces of
rails or slideways and such have proven partially effective.
However, malfunctions continue to occur interrupting produc-
tion and at times requiring the entire casting machir.e to be
taken out of service since control switches are actuated by
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the shifting apparatus as it changes position. These control
switches must, for successful operation, function flawlessly;
however, of necessity, they are in the same environment.
Thus, malfunctions occur also due to spilled or splashed mol-
ten metal, slag or refractory damaging these control switches.
Besides causing interruptions to the operation of the casting
machine, the above described maladies cause an erratic or
rough travel of the shifter causing the cantilevered troughs
or lance to wave severely. This waving can result in im-
proper flow of the molten melt down the trough, splashing ofthe metal as it e~its the trough onto the mold and in some
cases destruction of the trough due to hitting the mold or
machine.
The present invention is directed to an apparatus
for shifting the trough of a centrifugal casting machine of
the retraction casting type, including an elevated support
member, at least one upright suspension member hingedly con-
nected at its upper end to said elevated supported member and
suspended therefrom, a support plate hingedly connected to the
lower end of said upright suspension member, at least one
trough attached to said support plate, and means for recipro-
cating said upright suspension member to move said trough from
a first to a second position.
A further preferred form of the means provides
whereby the operating mechanism including control switches ~--
and valves are conveniently located in such a manner that
they are not affected by spills or splashes of molten metal, - -
slag or refractory. Overall the apparatus is simple and
easily maintained. Fur~er, complete access to the control
valves, switches and actuating mechanism is provided even dur-
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ing operation of the casting machine. Also, should a trough
dumping mechanism be desired, it may be mounted on the shifter
and the control valves and switches mounted along with the
shifter controls.
Figure 1 is an elevation view looking parallel to
the longitudinal axis of the trough.
Figure 2 is a partial elevation view looking 90 de-
grees to the longitudinal axis of the trough~
Figure 3 is an elevation view looking parallel to
the longitudinal axis of the trough and showing an alternate
embodiment.
The present invention can be better understood by
referring to the drawings and, in particular, Figure 1. Ap-
plicant's trough shifter is suspended from beams 10 by means
o~ brackets 12 attached thereto and hinge pins 14 inserted in-
to holes provided in the brackets and pins 14 further extend-
ing through tubular members 16 (shown in Figure 2) to which
upright members 18 have been welded. The hinge pins 14 are
held axially by snap rings 20. At the lower extremity of up-
right members 18 and welded thereto are tubular members 22(shown in Figure 2) through which hinge pins 24 extend. Hinge
pins 24 also extend through brackets 26 and are held axially
by snap rings 20. Brackets 26 are welded to support plate 28
upon which troughs 30 and 31 are mounted in a conventional
manner well known to those familiar with the art. An air or
hydraulic cylinder 34 is trunnion mounted opposite each of two
uprights 18. The cylinder rod is attached to the nearest
upright 18 in such a manner that actuation of the cylinder
swings the uprights 18 and thus the support plate 28 and all
it supports to and fro much like a swing. Since it is impor-
tant that the troughs 30 and 31 be positioned properly each
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time the shifter moves, an ad~ustable stop mechanism 36 is pro-
vided. It is preferred to limit the stroke of the cylinder on
the in stroke and mount the cylinder such that the full out
stroke is used. However, should it be more convenient ad~ust-
able stops can be employed in both directions. Also, a single
cylinder attached to only one upright 18 or to support plate 28
may be used in place of the preferred two cylinders 34 de-
scribed above. A limit switch 38 is actuated by limit switch
striker 40 which is attached to one upright 18 and thus moves
10 to and fro with the upright. This limit switch 38 signals a
control valve 42 for cylinders 34. The cylinders 34, control
valve 42 and limit switch 38, along with piping and wiring,
are protected by providing a sturdy enclosure 44. The enclo-
sure also provides room for other valves controlling other
mechanisms of the casting machine as well as an anchoring
point for beams 10. The enclosure 44 may be provided with an
access door and other desired conveniences not a part of the
present invention.
In an alternate embodiment as shown in Figure 3,
20 uprights 18 are placed closer together and support plate 28
cantilevered beyond one pair of uprights 18 with lance 32 be s
tween the uprights and trough 30 attached to the cantilevered
portion of support plate 28. Such an arrangement offers more
clearance above the trough for overhead crane service and
shortens the cantilevered portion of beams lOo , . ~
The shifter mechanism is so located that in the un- -
shifted position trough 30 is directly in line with machine
ladle 46 and support plate 28 is substantially horizontal.
In operation the troughs 30 and 31 are aligned ~ith
30 the mold 48 or, if a spray lance is being used, trough 30 and
lance 32 are aligned with the mold 48. The mold 48 is posi-
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tl.oned in front of the upwardly curvi.ng portion of trough 30
and molten metal from machine ladle 46 is dumped into the
trough 30. The mold 48 is rotated and metal from trough 30
pours onto the rotati.ng mold 48 which is retrac.ted from the
trough which distributes molten metal along the length of the
moldO When sufficient metal has been poured~ the ma~hine
ladle ceases to pour and the metal poured runs down the trough
with the except.i.on of a very small portion whlch soll.difies in
the trough. This solidif~ed portion called a "splinter" should
be removed prior to casting agaln in the moldO Removal may be
accomplished by mechanically rotating the trough to an inverted
position or by manually picking out the splinter~ In ei.ther
case the time required for removlng the splinter and perform-
ing any other required trough preparation can delay any sub- -
sequent cast. Thus, the first used trough is shifted clear of
the machine travel and the second trough is shifted into align ~`. .
ment with the mold, thus allowing a subsequent cast to com-
mence without delay due to trough preparationO
While the preferred embodiment and an alternate of
the invention have been described, i.t is not intended that the
invention be limited to the details shownO Various modifica- .
tions of structure and operating procedure will be obvious to
those skilled in the art and m~y be made without departing .:
from the scope of the following claimsO
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