IMPROVEMENTS IN AND APPLICABLE TO ROTARY LETTER-PRESS PRINTING MACHINES
Year: 1879

page_text: LETTERS PATENT to George Duncan and George Ashley Wilson, of Liverpool,
in the County of Lancaster, Engineers, for the Invention of "IMPROVEMENTS
IN AND APPLICABLE TO ROTARY LETTER-PRESS PRINTING MACHINES."
Sealed the 3rd October 1879, and dated the 7th April 1879.
PROVISIONAL SPECIFICATION left by the said George Duncan and Georgo
Ashley Wilson at the Office of the Commissioners of Patents on the 7th April
1879.
GEORGE DUNCAN and GEORGE ASHLEY WILSON, of Liverpool, in the County of
Lancaster, Engineers. "IMPROVEMENTS IN AND APPLICABLE TO ROTARY LETTER
PRESS PRINTING MACHINES."
This Invention relates to letter press perfecting machines in which the type or
stereotype forms for printing the paper on both sides are placed and secured on the
same cylinder. The object is to construct and adapt such machines for being
supplied with paper from the web, and to provide means for turning or reversing
the paper after it has been printed on one side.
In carrying the said Invention into practice we feed a web of paper continuously
in any well known or desired manner to the printing cylinder so as to receive
impressions on one side, and we provide mechanism for severing such web into
sheets either before or after the said impressions have been received.
The paper
which leaves the printing cylinder severed into sheets, and with impressions on one
side only, has to be led back to the printing cylinder to receive impressions on the
opposite side. In order to effect the above we employ the following novel arrange-
ments and combinations of mechanism :-
it
A cylinder or other suitably shaped rotating body is fitted with a gripper or
grippers, which seizes or seize the leading edge of each sheet, and carries or carry
forward until the tail edge of the said sheet is opposite to a gripper or grippers
contained in a second rotating cylinder or other suitable device. At or about this

page_text: moment the gripper or grippers in the first cylinder or its equivalent above men-
tioned leave or leaves the leading edge of the sheet free, and the gripper or grippers
in the second cylinder or its equivalent seizes or seize the sheet by the tail edge,
and carries or carry it forward to tapes or the like. The said tapes or the like carry
the sheets back to the printing cylinder to receive impressions on the blank side,
and so be perfected.
One, two, or more webs of paper may be used in conjunction with one printing
cylinder, in which case a corresponding number of sets of turning or reversing
cylinders or their equivalents will be required.
The turning or reversing cylinders or their equivalents are fitted with one set of
grippers when their circumferences are equal to a little more than the length of the
paper to be reversed. Two or more pairs of grippers are fitted to the said cylinders
or their equivalents if their circumferences are two or more times the length of the
sheet. When it is desired that variously sized sheets should be printed from one
cylinder, the turning or reversing cylinders are operated by means of excentric or
like gear. The grippers receive motion from cams or equivalent mechanism.
The type or stereotype forms may extend completely or only partly round the
printing cylinder, or two or more sets of forms may be fitted on the one printing
cylinder.
When the forms do not extend completely around the said printing cylinder, the
web of paper or the sheets is or are led to and from the surface of the said printing
cylinder in such manner that each portion of the web or each sheet shall receive an
impression.
After the sheets have been printed on both sides or perfected they are carried
away from the printing cylinder and laid by any ordinary mechanism.
It will be seen that when sheets of paper are perfected by receiving impressions
from a cylinder which is fitted with forms for both sides of such sheets the said
sheets will be laid alternately or in numbers with reverse side upwards. In order
to obviate the above defect we have devised the following novel arrangements of
mechanism :-
:-
First. The sheets are delivered alternately, or as desired, by means of vibrating
tapes or their equivalents to two sets or tapes or the like, one of which passes
directly over the laying table to the laying mechanism, whilst the other set travels
beneath upwards and over the top of the table so as to reverse the faces of the
sheets.
Second. We arrange and operate a fly or vibrating arms so as to deliver the
sheets alternately, or as desired, to the two sets of tapes above mentioned.
Third. We separate the sheets into two streams, as above mentioned, and lead
the said sheets to two separate laying tables.