Improvements in Platen Printing Machines.
Year: 1897

page_text: .
PROVISIONAL SPECIFICATION.
Improvements in Platen Printing Machines.
We, WILLIAM GUNSON, of 45, Medusa Road, Catford, in the County of London,
Manager, and WILLIAM FREDERICK PESCOD, of 21, Offord Road, Barnsbury, also in
the County of London, Engineer, do hereby declare the nature of this invention
to be as follows:-
This invention for improvements in platen printing machines relates to means
for regulating the pressure between the platen and the carriage of platen printing
machines in which the platen is drawn or thrust towards the carriage by means of
two connecting rods whose motion is derived from the main driving shaft of the
machine, the limits of the angular reciprocating motion of the platen, and con-
sequently the pressure between it and the carriage, being regulated by two eccen-
trics on a cross shaft capable of limited angular motion in its bearings so as to
vary the effective distance between the centres of the platen pins and cross shaft,
and the said eccentrics being connected to the platen pins by means of two
connecting fulcrum rods.
The object of this invention is to provide means for readily varying the angular
positions of the beforementioned eccentrics so that the effective distance between
the centres of the cross shaft and the platen pins, to which the platen ends of the
connecting fulcrum rods are connected, may be varied, thereby causing the limit
of approach of the face of the platen to the carriage, and the consequent pressure
thereon, to be correspondingly varied.
One arrangement of apparatus constructed according to this invention comprises
two principal parts, one of which is fitted loosely on to one end of the before.
mentioned eccentric shaft while the other part is keyed or otherwise secured to
it, the two parts being.coupled together by means of a clamping bolt or stud pass-
ing through, or secured in, one part and working in a slotted hole in the other. One
part is provided with a toothed segment in which a worm, held in position by lugs
on the other part, engages to adjust the impression. In making the adjustment
the two parts are freed by first unscrewing the nut of the clamping bolt or stud
after which by means of the worm and segment, they are adjusted to the required
position, the nut on the clamping bolt being then tightened to rigidly couple the
parts together again.
In order that the amount of impression obtained may be ascertained by inspec-
tion, an index is marked on one of the parts with a pointer suitably connected to
the other part, or to the cross shaft.
Doted this 20th day of January 1897
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C.; Agents.

page_text: plated rinting Machines.
We, WILLIAM GUNSON, of 45, Medusa Road, Catford, Manager, in the County of
London, and WILLIAM FREDERICK PESCOD, of 21, Offord Road, Barnsbury, also in
the County of London, Engineer, do hereby declare the nature of this invention,
and in what manner the same is to be performed, to be particularly described and
ascertained, in and by the following statement:-
1
This invention for improvements in platen printing machines relates to means
for regulating the pressure between the oscillating platen and, bed of printing
machines in which the platen is drawn or thrust towards the bed by means of two
connecting rods whose motion is derived from the main driving shaft of the
machine, the pressure between it and the bed being regulated by, two eccentrics
or crank pins on a cross shaft capable of limited angular adjustment in its bear-
ings, and the said eccentrics or crank pins being connected to a back shaft on the
bed carriage by means of two connecting rods so as to vary the effective distance
between the platen and bed.
The object of this invention is to provide means for readily varying the angular
positions of the said eccentrics or crank pins so that the effective distance between
the centres of the cross shaft and the back shaft of the bed or carriage, to which the
ends of the connecting rods are connected, may be varied, thereby causing the
limit of approach of the face of the platen to the bed, and the consequent pressure
thereon, to be correspondingly varied.
In the accompanying sheet of illustrative drawings: -
Fig. 1 is a side elevation of an apparatus constructed according to this inven-
tion and Fig. 2 is an end elevation of the same.
The invention comprises two principal lever arms one, a, of which is mounted
loosely on the cross shaft 6. secured in suitable bearings in the machine frame,
while the other c is formed with an open strap d and secured to the said shaft in any
position by means of a clamping screw e:
.
:
The lever arm a is provided with a bar f working in suitable guides g h and
carrying a tooth i capable of engaging in notches in a segment m in which it is
normally held by a spring n, and from which it may be readily released by
pressing the head o.
A toothed segment p on the extremity of the lever arm c gears with a worm q
mounted in lugs e and held in position by a cap bracket s so that on rotating the
said worm, the relative angular positions of the two lever arms are varied. They
are coupled together in any position by means of a clamping bolt t which passes
through the arm a and slotted hole v in the arm c, and is firmly secured by a nut w.
At each end of the shaft is an eccentric or crank pin on which is mounted
one end of a connecting rod y, the other end being connected to the back shaft of-
the bed carriage. In order to adjust the pressure between the bed and platen the
tooth is caused to engage in a suitable notch in segment m; the lever arms
being then freed by unscrewing the nut w, when the final adjustment is made by
means of the worm g and the two lever arms again rigidly coupled together by
means of the clamping nut w.
Having now particularly described and ascertained the nature of our said in-
vention, and in what manner the same is to be performed, we declare that what we
claim is:
:-
1. In platen printing machines; a means for regulating the pressure between
the oscillating platen and bed comprising two lever arms mounted, one loosely and
the other securely, on an eccentric or crank shaft (to which the bed carriage rods

page_text: are connected), and capable of relative angular adjustment by means of a worm
and segment, and of adjustment as a whole by means of a sliding tooth engaging
in a corresponding notched segment, the whole substantially as described.
2. In platen printing machines, a means for regulating the pressure between
5 the platen and bed, the whole arranged constructed and operating substantially as
described and shown in the drawings.
Dated this 20th day of October 1897
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.