Improvements in the Casting Mechanism of Linotype Machines.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in the Casting Mechanism of Linotype Machines.
We, WILLIAM HENRY LOCK, Manager and Secretary of The Linotype Company,
Limited, of No. 188, Fleet Street, in the City of London, and JOHN PLACE,
M.I.M.E., of The Linotype Works, Broadheath, in the County of Chester,
Engineer, do hereby declare the nature of this invention to be as follows:-
The present invention relates to improvements in the casting mechanism of
linotype machines, and the object of it is to improve that mechanism in respect
of the way in which it automatically adjusts its effect to the varying capacity of
the mould.
The well known metal pump is replaced by a force pump adapted to deliver
compressed air upon the surface of the molten metal in the metal pot. The air
duct between those two, is provided with a valve capable of throttling the air
current. The valve is held down on its seat against the passage of the air from
the air pump by a spring which is compressible by an eccentric or equivalent
inclined surface for the purpose of varying the strength of such spring. There
are combined with the lever by which the last mentioned surface is moved to
vary the strength of the spring, an index and graduated scale of mould
capacities.
The mode of operation is as follows. When the index points to the maximum
capacity on the graduated scale, the spring is free from compression by the
eccentric above mentioned; and the maximum volume of air compressed to the
maximum pressure, passes the valve and reaches the surface of the molten metal.
When that index points to any smaller capacity on the scale, the spring is
The throttling above
strengthened and the air duct is throttled accordingly.
described may be replaced by or combined with the opening of an exhaust adapted
to reduce the pressure of the air and to therefore reduce the effect of the compressed
air upon the molten metal to a corresponding degree.
301
1
1 1900
COMPLETE SPECIFICATION.
Improvements in the Casting Mechanism of Linotype Machines.
We, WILLIAM HENRY LOCK, Manager and Secretary of The Linotype Company
Limited, of No. 188, Fleet Street, in the City of London, and JOHN PLACE,
Price 8d 1

page_text: M.I.M.E., of The Linotype Works, Broadheath, in the County of Chester,
Engineer, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
In linotype pumps as hitherto constructed or proposed, the metal is ejected by
the piston acting upon it direct or through an interposed body of air. The pre-
sent invention consists in means for enabling the pump to automatically adjust
its effect to the capacity of the mould cavity in which the linotypes are cast.
Linotypes vary in length or thickness, or in both, and the capacity of the
mould cavity must vary accordingly.
The accompanying figure is a transverse section illustrating the application of
the invention to the metal pot of the Mergenthaler Linotype machine.
V40 is the cylinder of the force pump; V4, its piston: V42, its piston rod
working through the cylinder cover V43; V4, the air supply port establishing a
communication through the piston rod V2 and piston V41 between the outer air
and the under side of that piston.
The piston rod V42 is worked by a rod V5 which is passed down through a
pair of guides V46 fast on the top end of the piston rod V42. The rod 5 engages
with the piston rod V2 by a boss V66 on it between the guides V46. There is a
cushioning spring VG between each of those guides and the boss V66. The latter
is preferably a nut so that it can be moved up or down the rod V45 to adjust the
time of the stroke of the piston V. The bottom end of the rod V45 is coned to
form a valve V47 which controls the bottom end of the port V above mentioned
where it passes through the piston V4. The mechanism by which the rod V45 is
worked is not included in the figure, because it is not affected by the present
invention. The said rod is raised by a cam and lever or equivalent mechanism
and depressed by spring pressure released thereby, such as is used in the well
known Mergenthaler machine above mentioned to work the piston of its metal
pot. The details of the air supply to the force pump form no part of the pre-
sent invention. They may be varied as may be desired.
V48 is the air delivery pipe from the cylinder V40 to the metal pot V. V49 is
the cylinder of the metal pot. It is modified to meet the requirements of the
present invention by being continued upwards and connected air-tight with the
respective end of the pipe V4S V50 is a port in the side of the cylinder V.
It is controlled by the valve V51 which opens inwards before the pressure of the
metal in the pot V outside the cylinder V49, to admit metal into the latter. 210
is the usual throat leading from near the bottom of the cylinder V and opening
out through the mouth piece v12, as heretofore. The object in having the pipe V48
deliver into a restricted area like the cylinder V49, instead of into the metal
pot V (even when that is enclosed air-tight) is to concentrate the energy of the
air current upon an area of metal no larger than is necessary for proper ejection
of it through the throat 10 and mouth piece 1, instead of allowing that energy
to be dissipated over the entire surface of the metal in the pot V. The cylin-
der V may be dispensed with if preferred, but in that case the pot V must
be enclosed air-tight, the pipe V48 being connected air-tight with its cover or
with its side near that cover. The pot is carried upon legs 22 pivotted by their
bottom ends upon the frame of the machine, in order that it may be swung to
and from the linotype mould. To accommodate itself to that motion, the pipe V48
is flexible accordingly.
The means above mentioned for enabling the pump to automatically adjust its
effect to the capacity of the mould or, in other words, to the weight of metal to
be ejected from the metal pot V, consist in the combination with the pipe V48
which leads the air from the force pump V40 to the pot cylinder V49, of a valve
adapted to normally throttle it and a device capable of weighting that valve
according to the weight of metal to be ejected or capacity of mould to be filled.
V is a valve capable of throttling the pipe Vis and having its body V53

page_text: It
arranged accordingly as part of that pipe. V is the spindle of the valve.
asses out through the valve body V55, is prolonged beyond it for a distance not
ess than the maximum play of the valve V2, and terminates in a flat plate V56.
The valve 2 is held down on its seat V53 for the purpose of normally holding
the pipe V8 throttled, by the spiral spring V8 surrounding the spindle V4 and
pulling on the plate V56 from the gland V6 to both of which its ends are respec-
tively made fast.
The weighting device illustrated consists of a cam V57 mounted upon a suitable
axis V59 60 is a hand lever by which it can be turned. V61 is a graduated arc
supported in a plane adjacent to that in which the lever V60 works. V62, V62
are notches coinciding with the graduations; and V63 a detent on the lever VGO
adapted to engage in any one of those notches for the purpose of holding the
lever V in the corresponding position. The figure shews the axis V59 and the
arc V6 supported by a bracket V4 springing from the side of the cylinder V40.
The graduations and their notches V correspond with the several mould capa-
cities, while the contour of the cam V57 corresponds with their graduation, the
maximum radius of that cam being on the same side of the axis V59 as the
graduation and notch of lowest value.
The invention acts as follows. Compressed air is driven along the pipe V48 by
the descent of the piston V41. As soon as its pressure in the cylinder V49 exceeds
the pressure of the metal in the pot V outside that cylinder, it closes the valve V51
and holds it closed, at the same time acting piston-wise upon the metal in the
said cylinder, driving it up the throat 10 and out through the mouth piece 12
into the linotype mould. Obviously the volume of metal so driven up and out,
corresponds exactly with the volume of air added by the down stroke of the
piston V to that previously in the cylinder V49. So long as the defent V63
is on the notch V62 of highest value, the maximum volume of air at maximum
it and reach the cylinder V49, because with that position of the
pressure will .pass
detent. the cam V57 stands with its minimum radius over the plate V56, the
valve V52 being then free to open to the full before the air pressure on the pump
side of it. When, however, the detent V63 is in any notch of lower value, the
cam 57 stands with a longer radius over the plate V6 and obstructs the lift of
the valve V5 accordingly, whereby the air pipe V4s is throttled to a corresponding
degree, and the volume of air that reaches the metal in the cylinder V9 corre-
As soon as the valve V47 opens the
sponds with the value of the said notch.
port V, the pressure in the cylinder V drops to nornral and the weight of the
metal in the pot V outside that cylinder, opens the valve V and flows into the
cylinder, as illustrated, till it fills it up to its own level.
The throttling above described may be replaced by or he combined with the
opening of an exhaust adapted to reduce the pressure of the air, thereby reduc-
ing the effect in the cylinder V49 accordingly.
The particular cam and lever device described above for weighting the valve
may be replaced by any other capable of discharging the same function."
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, we declare that what
we claim is:-
-
1. The herein before described combination of force pump; enclosed metal pot;
air delivery pipe leading from the said pump to the surface of the metal in the
latter and connected air-tight to both; and a valve in the said pipe under the
control of a variable weighting or equivalent device.
2. The herein before described combination of force pump; enclosed metal pot
having throat and cylinder; air delivery pipe from the said pump to the top of
the said cylinder; and an automatic valve to the latter adapted to admit metal
into or to prevent it flowing into the cylinder according to the air pressure
5 therein relatively to that of the metal outside.

page_text: 3. The herein before described combination of force pump; enclosed metal pot;
air delivery pipe from the said pump to the surface of the metal in the metal
pot; weighted valve in the delivery pipe; and means for adjusting the lift of the
said valve according to the capacity of the mould.
4. The hereinbefore described combination of force pump; metal pot; delivery
pipe from the force pump to the said pot and making air tight connection with
both; valve in the delivery pipe controlled by a cam or an equivalent device
adjustable according to the capacity of the mould; means for adjusting the said
cam or the equivalent weighting device; and a scale indicating the proper adjust-
ment.
5. The hereinbefore described combination of force pump; metal pot having
throat and vertical cylinder: delivery pipe from the force pump to the said
cylinder and making air tight connection with both: valve in the delivery pipe
controlled by a cam or an equivalent device adjustable according to the capacity
of the mould; means for adjusting the said cam or equivalent device; and a
scale indicating the proper adjustment.
Dotad this with day of December 1898.
CHAS. S. WOODROFFE,
Agent for the Applicants.