Improved Safety Guard for Platen Printing Machines.
Year: 1899

page_text: Improved Safety Guard for Platen Printing Machines.
MAXIMILIAN THOMAS BARBER, Letterpress Printer, 37, Fountain Street,
Manchester, GEORGE NAPIER, Joiner, 44, Navigation Road, Altrincham, do hereby
declare the nature of this invention to be as follows:-
Our invention is applicable to platen printing machines, and is designed to
prevent all risk of accident to the person feeding or supplying sheets on the
platen through the hand of the feeder being caught between the platen and
the type forme when they are brought together to make the impression. This
movement has hitherto been a fruitful source of serious accidents to the operator's
hand. Our invention consists of pivotted links or bars which are attached to
side of machine; these may be pivotted to the platen frame, the arms, or other
part of machine (as the various styles of platen machines will admit of) to give
the necessary lifting movement.
The parts of our improved guard are as follows:-
_
A front guard bar or link which is pivotted or hinged to the top of a vertical
lifting bar.
A vertical lifting bar which is pivotted to the platen frame side, the arms,
or any part of machine to obtain the necessary rising movement (as the various
styles of platen machines will admit of).
Also connecting links which are pivotted to the lifting bar, these being also
connected with other parts of the machine to keep it and the front guard bar
in position when the platen is opening or closing.
The front guard bar is pivotted or hinged at right angles to the lifting bar,
and extends along the front of platen, rising and falling in a horizontal position.
The movement of this guard is similar to the platen, it rises from below the
top edge of the platen, has a forward advancing movement, and, rises sufficiently
above the top edge of the platen, when closed, to lift the hand clear of danger
before the platen and type forme meet, and so avoids all risk of accidents to
the operator when feeding in the sheets. These link arrangements may be
fixed to both sides of machine if necessary.
As platen machines are of various construction we do not limit or tie ourselves
to fix these links or bars to any particular part of machine, but to pivot to such
parts of the various machines that will give the movement to the front guard
bar already described.
Dated this Thirty-first day of December One thousand eight hundred, and

page_text: Improved Safety Guard for Platen Printing Machines.
We, MAXIMILIAN THOMAS BARBER, Printer, of 37, Fountain Street, Manchester,
and JANE NAPIER, of 44, Navigation Road, Altrincham, Widow and Adminis-
tratrix of the estate of the late George Napier, 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: -
Our said invention relates to improvements in guards or fences for platen
printing machines for preventing accidents to the printer.
In the accompanying drawings which illustrate the invention
Figure 1 is a side elevation with the guard depressed clear of the platen.
Figure 2 is a corresponding side elevation showing the raised position of the
guard when the platen is in contact with the type bed.
Figure 3 is a part elevation of a guard hinged at one side only.
Figure 4 is a front elevation of a guard hinged at both sides.
In Figures 1 and 2 the main frame A carrying the type bed at B, and the
oscillating platen C are indicated by dotted lines. In many types of platen
printing machine the platen is partly operated by side levers D) and arms D₁
driven by suitable gearing from the main driving shaft A¹ of the machine.
These particular means for operating the platen form however no part of the
present invention and they are merely utilised and shown by way of example
as a convenient source from which to operate the guard.
At the side of the platen is a lever b which acts as a carrier for the guard.
The lever is fulcrumed at 61 to a spur or projection 62 rigidly attached at about
right angles to the boss of the arm D¹ which carries the platen. The lever b
is connected with the side arm 1 by a link 63 hinged at 64 and at b5 to brackets
fixed on the lever b and the side lever D.
The guard is carried at the upper end of the lever b and extends across the
platen from side to side.
When the parts are in the relative positions shown in Fig. 1 the platen is
away from the type bed to enable the operator to lay on the platen the sheet
to be printed. In this position the guard e is at its lowest point and presents
no obstacle to the insertion of the sheet. When the platen is caused to advance
towards the type bed by the mechanism provided in platen machines for that
purpose the arm D₁ gradually changes its angle to the side lever D until when
in actual contact with the type bed as illustrated in Fig. 2 the arm D¹ has
moved through about a right angle and has become approximately parallel to
the side arm D. The spur 62 partakes of this change of direction with the
result that the lever is lifted and owing to the restraint of the link b³ it is
caused to turn about its fulcrum 6' with the result that the guard c traverses
approximately the path indicated by the dotted liner in Fig. 2 accompanying
the platen while at the same time gradually rising above it and lifting away
the hand of the operator prevents it from being trapped against the type bed.
As the platen returns for the reception of another sheet the action of the
lever is reversed and the guard is lowered out of the way.
Although only one side of the machine has been described it is to be under-
stood that the parts may be symmetrically arranged on the other side.
If the guarde is rigidly connected to the lever b it is liable to introduce
new dangers of its own since if in rapid working the operator were to pass his
hand over the edge of the platen during the return stroke it would become
trapped between the guard and the platen.

page_text: To prevent such accidents the guard c is so hinged to its carrier 6 that while
rigid and capable of resisting a downward pressure it may be non rigid or
capable of yielding from the underside.
In Fig. 3 the guard c is a bar or light tube hinged at c¹ to the carrier & in
such a way that while free to turn upwards it cannot without excessive force
be turned downwards.
Fig. 4 shows a similar guard c hinged at both sides at c¹³ and divided in
the middle.
Although we have shown a particular method of operating the carriers b
from the side arms D it is to be understood that the carriers b may be operated
from any other convenient rotating or reciprocating part of the machine.
We are aware that in such machines it has been proposed to use lifting
guard bars rising with the platen and we wish it to be understood that we
herein make no claim to lifting guard bars generally but only to the particular
constructions hereinbefore described and as hereinafter claimed.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is:-
For preventing accidents in a platen printing machine a guard c carried by
one or more carriers such as 6 adapted to accompany the platen so as to lie
below the edge of the platen when printing material is being inserted to rise
above the platen as it approaches the type bed and hinged to the upper end
of the carrier or carriers in such a manner that while rigid and capable of
resisting a downward pressure it can yield to pressure applied to the underside
substantially as set forth and shown.
01
1000
E. T. WHITELOW, A.M.Inst.C.E.,
70, Deansgate, Manchester, Agent for the Applicants.