IMPROVEMENTS IN AND APPERTAINING TO MACHINERY FOR MAKING SAND MOULDS FOR METALLIC CASTINGS
Year: 1879

page_text: PROVISIONAL SPECIFICATION left by William Phillips Thompson at the
Office of the Commissioners of Patents on the 22nd August 1879.
WILLIAM PHILLIPS THOMPSON, of Tranmere, in the County of Chester, Civil
Engineer. "IMPROVEMENTS IN AND APPERTAINING TO MACHINERY FOR MAKING
SAND MOULDS FOR METALLIC CASTINGS."
This Invention is for the same class of machines as that for which Letters Patent
were granted to me and dated the Twenty eighth day of October 1878, No. 432!,
which my Firm have been working up to the present time.
First. I fix the plate surrounding the pattern hereafter called the "filling plate,"
rigidly to the stationary or reversing table, and fasten the pattern or pattern plate
to a block moving in vertical guides in the table, but whose height in the table is
regulated by a cain or cams, double wedges, or other simple mechanism for raising
it up level with the filling plate, or lowering it so as to withdraw the pattern from
the sand through the filling plate.
.
Second. Round the filling and pattern plates I place a frame hereafter called the
"flask frane," whose inner surface has the same contour as the box to be moulded
from. This frame is supported on springs or counterweights and free to rise to a
height where it is stopped by easily regulated stops. These stops can be composed
of washers round a bolt or pin passing through brackets on the standard framework
of the machine and through holes in the flask frame; by altering the thickness of
these washers between the bracket and the flask frame the exact height at which the
flask frame stands is regulated. Screws, wedges, and other mechanical means can
be used, or sliding pins in the case of reversing machines. If it be a reversing
machine the same eccentric actuates both pattern plates, the same springs or
weights actuate both flask plates and bear against both. On the flask frame
I place the flask or box, the pin fitting into a socket or the socket onto a pin on
flask frame, as the case may be, or loose pins can be inserted into or pass up into
the sockets of flask frame when required.
Third. The sand drawer when used is formed of a series of drawers both side
ways and vertically, so that the amount of sand can be regulated exactly according
as I pull out one drawer or several. The lower or middle part of the hopper is
preferably of leather, or otherwise, telescopic, and the drawers are supported on a
frame adjusted vertically so that different heights of flasks can be used. The

page_text: bridge between the drawer and flask, if any, can be of plate or cast iron supported
on springs below the bottom drawer, or is attached to the adjustable frame of the
drawers and is hinged. The drawers can be worked by hand easily pulling out one
or more at a time, or by means of a piston-rod-head of a hydraulic or steam
cylinder, or by a rack and pinion, or other mechanical device as most convenient;
or I do without a drawer altogether, and make my table to slide on a gantry under
a hopper having a riddle and shaker below. When filled with sand (if on a
gantry) it is passed on to a stop placed so as to stop under a vertical plunger or
flat plate which descends slowly on it, and by power, weight, or springs, is forced
down onto the filled flask; the flask is forced down and the flask plate with
it as far as the weight applied or force will let it, the amount of weight or force
in the case of a hydraulic or steam cylinder being adjustable at pleasure. If not
on a gantry the table is vertically under the plunger. The plunger then rises,
the pattern, if made removable, withdrawn by a turn of the eccentric, and the
completed mould lifted off the flat "follower" plate or flat plate surrounding the
pattern. I sometimes add projecting pieces to the plunger to press into the sand
and condense it at certain points. Sometimes it is desirable to mould on the
Lancashire plate system, in which case the patterns are simply fastened to or cast
with a flat plate like the filling plate above mentioned, or attached to the table, and
after the pressure has been applied to the mould a series of smart taps are given to
the box to loosen the sand from the pattern before withdrawal. This tapping can
if desirable be done by machinery, but I prefer at present a hand hammer. Some
times however when a shaft and cam are used to press down the pressing plate onto
the flask or box, I arrange that while the pressure plate is firmly down two or
more hammers shall be let fall by the cam and strike the plate or sides of the
flask.
It can be made to riddle its own sand by a riddle being placed on or near the
top of the hopper, it presses the mould, withdraws pattern, and all preferably
without a single wheel, cam, shaft, or other like mechanism except a hand eccentric
for withdrawing pattern, a hydraulic cylinder, or a cam above the sand, not below
as usual, and a shaker (of any sort) for the riddle, thus doing more work than any
other moulding machine I know of, and without any of the complicated machinery
so troublesome to keep in repair in the gritty atmosphere of a foundry. When a
foundry is specially arranged for my Invention I use the gantry variation, and
arrange a series of machines with their cams all driven from the same slowly revolving
line shaft. Cams or other mechanism on the saine shaft also shake the riddles if
used, and "Jacob's ladders," elevators, or screws, worked from same shaft feed the
hoppers. In such case the cams are arranged with clutches so that they can be
thrown out of gear independently, and the plunger cams kept at their highest point
of stroke by catch when desired. Sometimes I supply the sand.to an archemedian
screw trough above and do away with hoppers altogether, their place being supplied
with hanging spouts or sleeves from the archemedian screw trough, furnished with
a-slide or valve both at top or bottom, worked at will by the operator by means
of handles.