Improvements in Printing Presses. PRINTING PRESSES
Year: 1886

page_text: Improvements in Printing Presses.
a I ALFRED GEORGE BROOKES of the firm of W Brookes & Son of 55 & 56
Chancery Lane in the County of Middlesex Fellow of the Institute of Patent
Agents do hereby declare the nature of my invention for IMPROVEMENTS IN
PRINTING PRESSES and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
This invention relates to the mechanism for operating the platen and inking rolls
of a printing-press, and especially to the means employed to obtain a "dwell" or
"stand-still" of the platen when farthest removed from the face of the type on
the bed, and it further consists in the combination with the bed and platen of a
printing-press and a rotary crank shaft, of a system of levers, links, and connecting-
rods, arranged in a novel manner which will be best understood by reference to the
description of the drawings and to the claims to be hereinafter given.
Of the drawings-
Figure 1 represents a side elevation of a printing press embodying my invention.
Figure 2 represents a rear elevation of one side of same and the train of
mechanism upon that side of the machine for operating the platen and inking-rolls
and
Figure 3 represents a diagram to be hereinafter referred to.
A is one of the two side frames of the press, which frames are connected together
by the type bed and suitable tie-girts (not shown).
B is the driving shaft mounted in bearings in each of the side frames A, A and
designed to have a fly wheel secured thereto and may be driven by a crank and
treadle connection thereto or by a suitable driving pulley and belt.
To the driving shaft B is secured the spur pinion a, which engages with and
imparts motion to the spur gear wheel C secured upon the shaft D which also has
its bearings in each of the side-frames A.
To a crank pin b set in the gear-wheel C is connected one end of the pitman E,
the opposite end of which is pivoted at o to the lever F mounted upon the shaft F¹
or upon a stud projecting from the frame A.
To the lever F is pivoted at d one end of the link G the opposite end of which
is pivoted at e to one arm of the elbow lever H to the other arm of which is pivoted
at f one end of the draw-bar I the opposite end of which is pivoted to the platen-
yoke J which in turn is pivoted by its two arms to the frame A at g.
K is the platen secured to the yoke J by suitable adjusting screws and h h are
the nippers mounted thereon,

page_text: L is a slotted arm or lever which may be formed in one piece with the elbow-
lever H or secured to the shaft H independently thereof as may be desired.
This arm L has mounted in suitable bearings therein the sliding rod i to the
outer end of which is pivoted the saddle j.in which the inking rolls k, k have their
bearings, said rolls being guided while passing over the type form by the bearers
or guide ways 7 formed upon the frames A.
A spring m surrounds the rod i in the slot of the arm L, and serves to press the
inking rolls upon the type form, and the ink-distributing table J in a well known
manner.
The shafts F and H' extend across the machine and have bearings in each of the
frames A and have mounted upon their opposite ends duplicates, respectively of
the levers F, H and L, which are in turn connected respectively to a crank on the
shaft D, to the platen, and to the inking rolls by means of a duplicate pitman,
draw-bar and sliding rod and saddle precisely in the same manner as shown in
Figure 1.
It will be observed by reference to Figure 3 that at the time when the impression
is being given, the lower end of the pitman E and its crank-pin are just passing
the lower dead centre of the crank and at the same time the rear end of the draw-
bar I and its wrist-pin ƒ are just approaching the dead centre as indicated in the
position of the several parts shown in dotted lines.
It will also be observed that, by virtue of the peculiar arrangement of the several
parts, and the relative positions of the several pivotal connections thereof, and the
fact, that the lower end of the link G and its wrist pin d is carried some little
distance beyond or to the rear of the dead centre as indicated by the positions
shown in full lines in Figure 3, a substantial stand still or dwell of the platen is
obtained when in its lowest position, without any of the objectionable features
pertaining to the toothed segments iron in use and which this invention is intended
to replace, such for instance as the back lash, so called of the segments and a
certain jumping action which sometimes takes place when the segments are dis-
connected from each other by the disengagment of their teeth.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
1st In combination with the platen and bed of a printing-press an arm or lever
provided in its movable end with two wrist-pins,-a pitman connecting one of said
wrist pins with the operating crank by a closely fitting bearing-an elbow lever
provided with a wrist pin in the movable end of each arm, a link connecting one
of said wrist pins with the second wrist-pin in the first mentioned arm or lever―
and a draw bar connecting the wrist pin in the other arm of the elbow lever with
the platen yoke substantially as described.
2nd In combination with the platen and type bed of a printing press, the
shaft D-crank pin b:-the pitman E-the arm or lever F provided with the
wrist-pins c and d -the draw-bar I:--the levers H L-all connected together by
positive and unyielding connections and the saddle j connected to the lever L by a
yielding connection all arranged and adapted to operate substantially as and for
the purposes described.
1
1000