IMPROVEMENTS IN PRINTING MACHINERY
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by Robert Cumming Annand at the
Office of the Commissioners of Patents on the 18th August 1881.
ROBERT CUMMING ANNAND, of Peterhead, in the County of Aberdeen.
"IMPROVEMENTS IN PRINTING MACHINERY."
My Invention relates to the construction of a machine or press whereby printed
copies of a sheet on one or both sides may be obtained by using the type in the
flat, and also printing the sheet from the web and cutting it up afterwards into
the required size. The press is constructed with four platens arranged directly
abovo each other and guided and held in position by four vertical guides (one at
cach corner).
The uppermost and lowermost platens are held in position by screws with nuts
on the end of the upright guides, and may be raised or lowered by these screws at
each corner so as to give the requisite amount of impression to the sheet being
printed.
The two intermediate platens are placed with their upper and lower faces the
requisite distance from the faces of the fixed platens. These intermediate platens are
arranged to ascend and to descend by means of suitable machinery placed between
them. The type for one side of the sheet being placed on the lowermost stationary
platen, and the type for the other side being placed upon the upper moving platen,
the impression is by this means given to two sheets simultaneously. The
intermediate moveable platens are raised and depressed by eight cams actuated by
four rollers on two central shafts, these two shafts being driven in opposite
directions by suitable gearing, the rollers and cams being constructed to gear into
cach other as well as to bear on rolling surfaces. The operation may be described
as follows:-The end of the sheet from the web is carried over guide rollers, thenco
underneath the uppermost platen. While in this position it receives the impression
on one side of the sheet, when the platen on which is laid the type ascends. The
sheet is next carried round guide rollers with tapes and passes underneath the
lower moveable platen, where it receives an impression on the opposite side
simultaneously with an impression given by the upper platen to another part of
the web. The tapes and rollers which carry the sheet are driven by an intermittent
motion which allows the sheet to remain at rest while the impression is being given
to it, but as soon as the impression is given the sheet is advanced the required

page_text: distance for next impression. This motion is conveyed to the tape rollers by a cam
on a revolving shaft, and a connecting rod branching into two arms with a friction
check on each, set opposite and working on a suitable wheel on the end of the
leading tape roller. This connecting rod is so constructed that by turning two
screws the speed at which the sheet advances through the machine can be altered
to suit any size of printing. The ink is put upon the type by two sets of two
rollers (one for each set of forms) which are carried in their place by guides and
connected together by means of a pitch chain or other suitable arrangement and
made to pass over the type while the platens are sufficiently separated. The
intermediate platens are balanced by a set of levers which brings up the lower
platen by the weight of the upper ones descending. The machine can also be
arranged to print only one side of a sheet if required.