Year: 1897

page_text: I, THOMAS FORKNALL, Blake Street, Leicester, Printing Machine Maker, do
hereby declare the nature of this invention to be as follows:
This invention has reference to platen printing machines and embodies certain
improvements relating to the feeding of the sheet to the platen and its removal
therefrom after being printed.
In platen printing machines of ordinary construction, the blank sheet is placed
upon the reciprocating platen and after printing is removed therefrom by the,
hands of the attendant, but the object of the present invention is to provide means,
as hereinafter referred to, by which the said operation, which now involves the
intervention of the operator's hands between the platen and the forme or type, is
carried out automatically.
The invention comprises gripping devices, as hereinafter described, by means of
which each sheet is taken from the feed table, drawn on to the face of the platen
and held while being presented to the type and subsequently drawn off the platen
when the impression has been made and delivered on to a delivery board or into
a receptacle underneath the machine.
These gripping devices have a rocking or reciprocating motion imparted thereto
and according to one construction may consist of two members or jaws.
Each jaw may be mounted on a shaft having its bearings in an arm movably
suspended from or near each side of the platen so as to have a slight rocking or
reciprocatory movement bodily thereon when required as hereinafter described.
The said jaws have their acting or gripping ends located near the lower edge
of the platen, so that when the latter has travelled the full limit of its movement
away from the type, the grippers will be located near the edge of the feed table in
readiness to receive and grip a sheet and withdraw it from the said table.
The said jaws may be movable to and fro longitudinally on their respective
shafts to vary their relative positions apart for varying sizes of sheets.
The said jaws are maintained in position against the bottom edge of the platen
and also normally closed by means of suitable springs and the opening of the
said jaws to receive the sheet from the platen or to release the sheet after printing
as hereinafter described may be effected by contact with a cam, wiper, or arm or
equivalent means.
One of the said jaws instead of being mounted upon a separate shaft may be
pivotted to the side of the other jaw.
Their operation. is somewhat as follows:-
Just immediately prior to the platen finishing its stroke in a direction away

page_text: from the type bed to assume the position against the feed table in which the
grippers take the sheet, the jaws are, by contact with an arm or equivalent means,
opened ready to receive the sheet from the feed board and immediately the jaw
passes out of contact with the said arm, the grippers close upon the sheet and grip
it and as the platen returns to the type they draw the sheet off the feed table
and hold it during the time the impression is being taken.
An arm or arms or other device is arranged to subsequently come into contact
with the jaw and open it so as to release the paper and the said arm also further
moves the gripper bodily on its pivot hereinbefore referred to away from the
paper, whereupon a further gripping device or devices then takes hold of the
printed sheet and removes it from the platen.
These further or second gripping devices may be similar or nearly so in construc-
tion and operation to the other hereinbefore described, and be opened and closed at
the required times by contact with arms, wipers, or equivalent suitably arranged
in the path of the same.
In some cases a single jaw may be employed and arranged to grip the paper
against the end of the platen, the latter in such cases taking the place of the
second jaw.
The details of construction may be varied within certain limits without depart-
ing from the main lines of the invention.
BOULT & WADE,
Agents for the Applicant.
I, THOMAS FORKNALL, Blake Street, Leicester, Printing Machine Maker, 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:-
This invention has reference to platen printing machines and embodies certain
improvements in mechanism for taking hold of the sheet, drawing it off the feed
board on to the platen and holding it during the time the impression is being
taken.
The invention comprises sheet gripping mechanism having a rocking or recipro-
cating motion coincident with that of the platen itself as hereinafter more fully
described in reference to the accompanying drawings in which,
Figure 1 is a plan of sufficient of a platen printing machine to illustrate my
invention which is shown as applied thereto.
Figure 2 is a side elevation partly in section on the line X X of Figure 1 show-
ing the platen and gripping devices in position to receive the sheet from the feed
board, the cam for actuating the gripping devices being shown in dotted lines.
Figure 3 is a similar view showing the platen in the position at the printing
of the sheet and the gripping devices moved under the platen to allow the printed
sheet to slide off the latter.
Figure 4 is an elevation on a smaller scale showing the feed board and the
mechanism for raising the latter to allow the platen to pass from under it when
moving towards the type-bed.
Only so much of the platen printing machine is shown in the drawings and will

page_text: be hereinafter described as is necessary to a clear understanding of the
invention.
A, represents the usual feed board which on its under surface near to one end
and at each side is furnished with an angle iron A¹ movably pivotted at A² to an
arm B which is screwed to and rises upwardly from the standard or framing C
in which the usual platen shaft D¹ revolves.
The said feed board has also pivotted thereto on one side and near to its opposite
end a connecting rod E attached at its other end to the longer arm E of a bell
crank lever, fulcrummed at E3 to the framing of the machine, while the shorter
arm E carries a roller E2 which bears against a cam F mounted on the platen
shaft D' and of such a contour that it causes the lever and connecting rod to raise
the front end of 'the feed board where it rests on the platen, so as to let the latter
pass when it is about to move with the sheet towards the type-bed for printing,
as shown in Figure 3.
G, represents the gripping devices which are carried on a shaft G and have their
acting ends normally located near the edge of the platen D as shown most clearly in
Figure 2 so as to be capable of clamping the sheet there-against as hereinafter
described.
Each of the gripping devices is fixed to the shaft by a set screw G* passing
through the tubular boss thereof and when the said screw is released the grippers
may be slid along the shaft to or from each other for different sizes of sheets.
The gripper shaft is supported by two arms H H' fulcrummed at H2 H3 one to each
side of the platen, and connected to each other by a tie rod H4 and nuts H5.
The arm H has an extension or continuation H beyond its fulcrum, to the
end of which is attached a spring J the other end of the latter being connected to
the platen so as to draw down the said extension on to a stop or pin D² projecting
from the side of the platen and cause the grippers to press against the edge of
the platen.
On the end of the shaft G¹ there is also fixed by a set screw K² a bell crank
lever furnished at the end of its longer limb K with a roller K3 bearing on the
peripheral edge of a cam L from which the gripping devices receive their motion.
The said roller is maintained normally in contact with the cam by the spring J
which causes the extension H of the arm H¹ to press against a pin K on the
end of the shorter limb K¹ and pull the bell crank lever so that its roller is kept
against the cam.
The cam L is mounted fast on the same shaft D¹ as the platen and arranged to
impart the requisite movements to the bell crank lever K K' arms H H and shaft G¹
to cause the gripping devices G to clamp the sheet against the lower marginal
edge D3 of the platen and hold it in that position while the impression is being
taken and then to move from under it so that the printed sheet can slide off the
platen.
From the foregoing description it will be observed that the gripping devices
have a movement to and from the type-bed and the feed board coincident with that
of the platen itself and a movement independent of the platen through the medium
of the cam L and interposed mechanism for the purpose of receiving and gripping
the sheet and of releasing the sheet after it has been printed.
The action of the mechanism is as follows:-
Assuming the various parts of the mechanism to be in the position indicated
in Figure 2, i.e. in readiness to receive the sheet which is supposed to have been
laid on the feed board.
Upon the cam L commencing to revolve in the direction indicated by the arrow,
the roller K3 will descend the incline L¹ upon which it is resting as shown, where-
upon the spring J will pull down the arm extension H on to the pin D2 and the
said arm extension pressing on the pin K will lower the lever K K¹ so that a
slight rocking motion is imparted to the shaft G¹ and the grippers G caused to press
on the end of the sheet and grip it against the edge of the platen.
Immediately the sheet is thus gripped against the platen the latter will com-

page_text: mence to move on its shaft towards the type-bed in the well known manner and
the sheet will be thereby drawn off the feed board A on to the face of the platen D.
Simultaneously with the platen commencing this movement the cam F acting
on the roller E2 will move the lever E2 E¹ & connecting rod E so as to raise the
front end of the feed board as indicated by the dotted lines in Figure 4 and allow
the platen to pass clear from under as shown by the dotted arc in Figure 3 which
represents the line of movement described by the said platen.
While the platen is moving towards the type-bed and the impression is being
taken the roller K³ is travelling round the circular edge of the cam L so that the
grippers remain holding the sheet against the platen.
When the impression is taken the roller ascends the other incline L2 of the
cam L whereupon the lever K K by its pin K4 presses against the arm extension H
which latter partly rotates the shaft G¹ and causes the grippers to move into a
position relative to the edge of the platen as shown in Figure 2 so as to release their
hold upon the sheet, the roller then ascends the highest part L3 of the cam so that
the pin K acts still further upon the arm extension and causes the grippers to
pass away from the sheet and to recede under the edge of the platen into the
position shown in Figure 3 so that the printed sheet can then slide off the face
of the platen into a receptacle placed under the machine to receive it.
Then while the said roller moves down the incline L' into the position shown in
Figure 2 the platen returns to its original position under the feed board preparatory
to receiving another sheet.
During the time the platen has been moving to and from the type-bed the
roller Ex has been travelling round the circular edge of the cam F and the feed
board has been kept raised as shown in Figure 4 but immediately the platen has
returned to its normal position indicated in Figures 2 and 4 the said roller enters
the recess in the cam F and the front edge of the feed board is lowered on to the
platen as in Figures 2 and 4.
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:
-
1. In a platen printing machine the use or employment of sheet gripping devices
having imparted thereto a rocking or reciprocating motion coincident with that
of the platen itself.
2. In a platen printing machine the combination with the platen of automatic
gripping devices arranged in such a manner as to grip the sheet and hold it in
position on the platen until the impression has been taken and then to release the
said sheet and move from under the latter for the purpose described.
3. In a platen printing machine the combination of sheet gripping devices
having a motion to and from the type-bed and the feed board coincident with that
of the platen itself and a motion independent of the platen by which the grippers
are caused to clamp the blank sheet against the edge of the platen end draw it
off the feed board and to subsequently release the said sheet after printing.
4. In a platen printing machine the combination with the platen of automatic
gripping devices arranged in such a manner as to clamp the sheet against the edge
of the platen and draw it off the feed board on to the platen and hold it in position
thereon until the impression has been taken and then to release the said sheet and
move from under it for the purpose described.
5. In a platen printing machine the combination with the platen of a shaft
and gripping devices thereon having a motion coincident with that of the platen
itself, a cam and mechanism between it and the said shaft to cause the grippers to
alternately grip and release the said sheet for the purpose described.
6. In a platen printing machine the combination with the platen of a shaft pro-
vided with sheet gripping devices and carried in arms fulcrummed to the side of
the platen, a lever attached also to the said shaft and acted upon by a cam sub-
stantially in the manner and for the purpose described,

page_text: 7. A platen printing machine provided with sheet gripping mechanism consist-
ing of the parts constructed, arranged and operating substantially in the manner
described and illustrated in the accompanying drawings.
Dated this 5th day of inonst 1808
Witness:
EN. LEWIS,
Berridge Street Chambers, Leicester.
THOMAS FORKNALL.
Boult & Wade,
conto for the Analicant