CERTAIN IMPROVEMENTS IN MACHINERY OR APPARATUS FOR ENGRAVING METALLIC CYLINDERS OR ROLLERS EMPLOYED FOR PRINTING CALICO AND OTHER SURFACES
Year: 1857

page_text: application for Letters Patent was not given within the time prescribed
by the Act.)
PROVISIONAL SPECIFICATION left by John Bradley at the Office of
the Commissioners of Patents, with his Petition, on the 7th August
1857.
I, JOHN BRADLEY, of Radcliffe, in the County of Lancaster, Engraver, do
hereby declare the nature of my said Invention for "CERTAIN IMPROVEMENTS
IN MACHINERY OR APPARATUS FOR ENGRAVING METALLIC CYLINDERS OR ROLLERS
EMPLOYED FOR PRINTING CALICO AND OTHER SURFACES," to be as follows:-
My Invention relates, first, to a novel method of transferring and reducing
certain patterns or designs from an enlarged diagram or figure to the surface
of metallic cylinders or rollers used in calico printing. The apparatus for
effecting this consists, first, in the employment of a horizontal bar, guided by
gradients, and moving laterally upon its fulcrum or centre, one end of the bar
being further from or nearer to the centre, according to the degree of dimi-
nution required, so as to act after the manner of a "pentagraph."
pentagraph." Upon
the lower surface of this pentagraph bar is a stud, working in and giving
motion to a horizontal sliding bar beneath it, (this bar slides from back to front
of the machine), which has a rack upon its lower surface, gearing into a
pinion which imparts motion to the cylinder by means of the dividing wheel
u0on the shaft upon which the cylinder is secured, and upon the upper surface
of the pentagraph bar is a stud, working in a slot formed in a sliding frame

page_text: bed or carriage above it, so that as the pentagraph is moved it imparts a lateral
motion (in a reversed direction to the tracing point) to the carriage, &c.
To this bed or carriage are attached two bands, passing round pulleys on the
sides of the machine, and secured to a second frame or bed, also traversing or
sliding in a lateral direction, but above the other bed, and in a reverse, direc-
tion to it, that is, both have a lateral motion across the machine but move
from the opposite sides of the machine... A similar effect may be obtained by
means of a screw and excentric, worked from the division wheel or other con-
venient part of the gearing. When "mills" are employed to engrave the
surface by indentation, such mills are placed either upon the upper traversing
bed, or upon both the upper and lower, working in a manner across each
other, producing two rows or lines of designs, and simultaneously, if required,
the "mills" being caused to impress or indent the pattern by any ordinary
apparatus at present employed. When points or "diamonds" are used to etch
or engrave by cutting, they may be similarly employed upon either or both
beds.
The second part of this Invention relates to a novel method of producing
or transferring the pattern to be engraved from the enlarged diagram to the
table of the machine, and which consists in so placing the diagram in a strong
light as to cast a shadow therefrom, which is cast or reflected upon the table
by means of a mirror or other polished surface, when, if the room be darkened,
the pattern may be traced, and thus the use of plates, cards, or templates is
dispensed with.