IMPROVED MACHINERY FOR PRINTING IN COLORS
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Thomas Arthur Middleton at the
Office of the Commissioners of Patents on the 17th September 1880.
THOMAS ARTHUR MIDDLETON, of Loman Street, in the Borough of Southwark..
"IMPROVED MACHINERY FOR PRINTING IN COLORS."
The object of this Invention is to provide a machine whereby the process of
printing in colors described in the Specification of Letters Patent granted to
William Brookes, dated 30th May 1876, No. 2268, may be efficiently carried out.
The machine is designed for the purpose of printing long lengths of material,
whether of paper or fabric, and consists of a long narrow framework, at one end
of which a pair of brackets are placed to carry the roll of paper or fabric to be
printed.
The material as it leaves the roll is passed between a pair of smoothing rollers
which are intended to smooth out any creases before the material is printed.
The
The printing surface, which is prepared in the manner described in the Specifi-
cation of the above mentioned Patent, is mounted in an adjustable frame.
material is drawn forward intermittently across this surface, and by means of
pressing rollers is pressed upon it and takes up the colors, after which the printed
material may be wound upon a roller suitably placed for the purpose.
The material is drawn forward by means of a pair of reciprocating grippers
arranged on opposite sides of the machine and connected by rods to cranks on the
main driving shaft. The length of stroke of these cranks may be adjusted
according to the amount of material to be drawn forward to correspond with the
size of the printing surface employed. The reciprocating grippers deliver the
material to a pair of stationary grippers which hold it securely during the printing
operation.
The grippers may be of any suitable construction, and may be opened and
closed and maintained in either position as required in any convenient manner.
The printing operation is effected, as before mentioned, by pressing the material
onto the printing surface by means of pressing rollers. These rollers, of which there
may be two or more, are mounted in a suitable carriage to which a reciprocating motion
is given as hereafter explained. This roller carriage slides in guides placed longi-
tudinally of the machine, and so arranged as to be capable of vertical motion,
whereby the rollers during the return motion of the carriage may be raised off the
material.

page_text: The roller carriage is connected by steel bands to two pairs of sectors, suitably
mounted, and to which an intermittent rocking motion is communicated from a
cranked shaft, which is driven by spur gearing from the main shaft.
The arrangement of the spur gearing for communicating the intermittent motion
to the sectors may be as follows:-On the main shaft is keyed a wheel which has
one half its periphery toothed and the other half plain. On the sector crank shaft
is keyed a spur pinion half the diameter of the said wheel, and so arranged as to
gear with its toothed part. A stop is attached to the side of the pinion which
rests upon the plain part of the wheel and so keeps the pinion from turning when
it is not in gear.
The effect of this arrangement is that the sector crank shaft makes one complete
revolution while the main shaft is making one half a revolution, and then stops for
the same period, thus giving time for the fabric to be advanced.
By this means an intermittent reciprocating motion is given to the roller
carriage.
The roller on which the printed material is to be wound is placed, by preference,
slightly above the top of the frame work, so that as the pressing rollers retire the
material will be, as it were, gently peeled off the printing surface.
This roller is
driven continuously, preferably by friction, so that during the printing operation
it will be allowed to slip, but will always be ready to take up any slack.
After an impression is taken the printing surface is slightly-raised-in-any-con--
venient manner to compensate for the amount of color that has been taken off, and
_to_bring it into the proper position_for_the_next_impression..
The material before being printed must be thoroughly saturated with turpentine,
which may be supplied to it before it is rolled on the supply roller, or the material|
may be passed through a trough containing the turpentine after it leaves the
smoothing rollers, the excess of turpentine being squeezed out by suitable squeezing
rollers.