IMPROVEMENTS IN' CHROMOTYPOGRAPHICAL PRINTING PRESSES
Year: 1857

page_text: application for Letters Patent was not given within the time prescribed
by the Act.)
PROVISIONAL SPECIFICATION left by William Smith at the Office of
the Commissioners of Patents, with his Petition, on the 15th June
1857. A communication.
I, WILLIAM SMITH, of No. 10, Salisbury Street, Adelphi (Civil Engineer),
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN'
CHROMOTYPOGRAPHICAL PRINTING PRESSES," a communication from A. E.
Rochette, of Vannes, but now of 36, Rue de l'Echiquier, Paris, to be as
follows:-
Colour printing under typographical presses has hitherto been performed
by several successive operations, the sheet of paper being taken out from the
tympan after the impression of each color. It is indeed very difficult to
get a fair correspondance of the colored letters in the several pages of the
sheet, which can be done only by mark points, and till the colors exactly
correspond, many sheets of paper, sometimes whole quires, are spoiled at each
change of color.
With this improved typographical press I can print several colours at once
in the same form, which press is divided into four compartments, each com-
partment containing characters for a different color. The sheet of paper to
be printed is laid securely on a moveable tympan, which is made to revolve
by quarters of a revolution after each stroke of the press. Four proofs by
this process are printed simultaneously on a sheet of paper, each proof with
a different tint or color, and successively each one with four colors. After
receiving four impressions the sheet, becoming loose, is taken out, and a new
one replaced on the tympan.

page_text: On the annexed Drawing, Fig. 1 is a general perspective front view of the
printing press on a small scale, and Fig. 2 shews the arrangement of the
plates in the form. The two principal features of this press are the tympan
and the form.
The tympan, Fig. 1, is composed of a square frame A, B, C, D, hinged on
the table T; a wheel R of 240 teeth is fitted between the inside edges of the
frame A, B, C, D, where it is free to turn, its outer circumference bearing on
small adjustable rollers, not shown in the Figure.
The sheet of paper P is held on the tympan's face by a suitable frame
a, b, c, d; the form is placed on the table T, each form being inked with
a different color, as shewn in Fig. 2. The whole machinery is fitted on a
strong framework E, E. The frisket F, K, hinged at the other end of the
table, is first lowered on the inked form, then the tympan is also simul-
taneously lowered, all by machinery driven by a hand crank, and the table is
brought under the pressing screw S, where the paper receives a first printing
of the four colors, as in Fig. 2.
The tube being then brought back to its first position, the tympan is raised
up, and the teeth of the wheel R are caused to take into those of the wheel r,
which makes one entire revolution, and causes the wheel R to turn one
quarter of a revolution; then it stops, the tympan is lowered once more, carried
again under the pressing screw, and the sheet receives a second impression.
The quarter of the sheet, that had been printed blue the first time, is now printed
black; the second quarter, that had been printed black the first time, is now
printed yellow; the third quarter, that had been printed yellow, is now printed
red, &c., each quarter of the sheet being printed successively with the four
colors, or the whole sheet in four successive strokes of the bar is printed
entirely with four colors, and it is then removed from the tympan.
The printed sheet is folded in 4, but the form could as well be arranged
for folding it in 8, 12, or 16, &c., and could be inked with 2, 3, 4, 5, 6, 8, or
more colors, requiring only three men to work it.
.
.
The mechanical contrivance being so combined as to suit the various
purposes for which it is required, the press can print all kinds of illustrated
works, colored plates, paper hangings, imitation of paintings, playing cards,
cloth, or stuffs of many descriptions, tapestry patterns, &c.