Guards or Protectors for Platen Printing Machines.
Year: 1899

page_text: Date of Application, 19th Dec., 1899
Complete Specification Left, 13th Sept., 1900-Accepted, 24th Nov., 1900
PROVISIONAL SPECIFICATION.
Guards or Protectors for Platen Printing Machines.
I, EDGAR ARNOLD PALLISTER, of Beeston Hill, in the City of Leeds, Clerk, do
hereby declare the nature of this invention to be as follows:-
This invention relates to guards or protectors for preventing accidents to
persons employed in feeding sheets of paper to platen printing machines.
With such machines, there is a risk of the attendant having his hands or
fingers trapped and crushed between the platen plate and the type bed, through
a sught delay in drawing away his hand arter feeding a sheet, as the platen
approaches the type bed plate, or vice versu. Also in some descriptions or
platen machines, in which the table to hold the sheets being ted, or after Leing
printed upon, is situated immediately behind the platen plate, and in which
imachines the platen plate is moved backwards and forwards, there is a risk of
the attendant's hands or fingers being trapped or crushed between the platen
plate and said table, for example, when reaching down to remove any sheets
which may have talien down between the platen and the table.
My invention consists essentially of a guard conveniently formed of sheet
iron, which is attached directly or indirectly in a hinged manner to the platen
plate, so as to partake of the movement or the top edge of the platen plate;
on which edge the rear edge of the guard rests during the greater part of the
movement or the platen plate, rising however sharply just before the platen and
the type bed are brought close together, thereby striking or lifting up the hand
of the attendant out of danger. As the platen and the type bed are the one re-
moved away from the other, the guard drops with its rear edge again on to the
top edge or the platen plate, so that the space between the platen plate and the
fixed table is always covered, whatever be the position of the platen; and the
risk trapping the hand of the attendant between these is entirely obviated.
In this specification the side of the machine facing the operator is for the
sake of distinction referred to as the front side, and the opposite the back
side.
י,
In the case of the Arab and many other platen printing machines it is
necessary to hinge the guard on a pair of trailing bars, which are themselves
hinged at their back ends close to the top edge of the platen plate, for which
purpose in the "Arab" platen machine, the blanket tightening rod can be very
conveniently utilized. The back end of the bars, during the working of the
machine, trail over the bearings of, or the impression shaft itself. This gives
a raising and falling movement to the bearings on which the guard is hinged,
enabling it to clear the underside of the table, or other parts, as required. As
the platen approaches the termination of the closing movement, the forward
arm of the guard, (considering the guard as a lever), catches against the under-
side of the table, or an attachment to the underside of the table, or other
equivalent projection, causing the back arm of the guard, i.e. the edge hitherto
resting on the top edge of the platen plate, to rise up sharply, moving the hand
of the operator out of the way of any danger.

page_text: In the "Arab" machine as at present constructed, I find it advisable to raise
the table slightly, to enable the guard to move as above described. Also the
shorter arm of the guard is bent slightly upward.
In other machines, such for example as those which have the table or tables
to one side of instead of straight in front of the platen, it may be necessary to
insert special supports to form the hinge and bearers for the trailing bars, and
special stops to cause the tilting of the guard.
Further in the case of machines in which the platen merely tilts about the
centre situated about the middle of the height of the platen, the tilting movement
of the platen plate is arranged to cause the tilting and moving to and fro of the
guard. In the "Arab" machine, the hinge of the platen is about its lower edge,
so that there is both a tilting and closing movement.
In other platen machines in which the platen is fixed and the type bed alone is
moved, the tilting of the guard is effected by means of bent levers, links and
cams from the most convenient moving part of the machine.
Dated this 18th day of December 1899.
J. CLARK JEFFERSON,
30, Park Row, Leeds, Agent for Applicant.
I, EDGAR ARNOLD PALLISTER, of Beeston Hill, in the City of Leeds, in the
County of York, Clerk, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and aseer-
tained in and by the following statement:-
-
This invention relates to guards or protectors for preventing accidents to
persons employed in feeding sheets of paper to platen printing machines.
With such machines, there is a risk of the attendant having his hands or
fingers trapped and crushed between the platen plate and the type bed, through
a slight delay in drawing away his hand after feeding a sheet, as the platen
approaches the type bed plate or vice versa. Also in some descriptions of
platen machines, in which the table to hold the sheets being fed, or after being
printed upon, is situated immediately behind the platen plate, and in which
machines the platen plate is moved backwards and forwards, there is a risk of
the attendants' hands or fingers being trapped or crushed between the platen
plate and said table, for example, when reaching down to remove any sheets
which may have fallen down between the platen and the table.
My invention consists essentially of a guard conveniently formed of sheet
iron, which is attached directly or indirectly in a hinged manner to the platen
plate, so as to partake of the movement of the top edge of the platen plate;
on which edge the rear edge of the guard rests during the greater part of the
movement of the platen plate, rising however sharply just before the platen and
the type bed are brought close together, thereby striking or lifting up the hand
of the attendant out of danger. A's the platen and the type bed are the one re-
moved away from the other, the guard drops with its rear edge again on to the
top edge of the platen plate, so that the space between the platen plate and the
fixed table is always covered, whatever be the position of the platen; and the
risk of trapping the hand of the attendant between these is entirely obviated.
In this specification the side of the machine facing the attendant is, for the
sake of distinction, referred to as the front side, and the opposite the back
side.

page_text: In the case of the
"
Arab and many other platen printing machines, it is
necessary to hinge the guard on a pair of trailing bars, which are themselves
hinged at their back ends close to the top edge of the platen plate, for which
purpose in the "Arab" platen machine, the blanket tightening rod can be very
conveniently utilized. The front end of the bars, during the working of the
machine, trail over the bearings of, or the impression shaft itself.
This gives
a raising and falling movement to the bearings on which the guard is hinged,
enabling it to clear the underside of the table, or other parts, as required. As
the platen approaches the termination of the closing movement, the forward
arm of the guard, (considering the guard as a lever), catches against the under-
side of the table, or an attachment to the underside of the table, or other
equivalent projection, causing the back arm or rear edge of the guard, i.e. the
edge hitherto resting on the top edge of the platen plate to rise up sharply, mov-
ing the hand of the operator out of the way of any danger.
"
Also the
In the Arab machine as at present constructed, I find it advisable to raise
the table slightly, to enable the guard to move as above described.
shorter arm of the guard is bent slightly upward.
In this and other machines, such for example as those which have the table
or tables to one side of instead of straight in front of the platen, it may be con-
venient or necessary to insert special supports to form the hinge and bearers
for the trailing bars, and special stops to cause the tilting of the guard.
Further in the case of machines in which the platen merely tilts about the
centre situated about the middle of the height of the platen, the type bed being
moved up to the platen, the tilting movement of the platen plate is arranged
to cause the tilting and moving to and fro of the guard. Substantially the
same device as above described will be applicable to such machines.
In machines both of the Arab and other types the tilting of the guard may
be effected by means of bent levers, links and cams from the most convenient
moving part of the machine.
And in order that my invention and the manner in which the same is to be per-
formed may be more readily and clearly understood, I have annexed hereto the
following drawings illustrating my invention.
Fig. is a longitudinal vertical section of an Arab platen printing machine
in which the guard is raised and lowered by a tail piece or tail portion of the
guard. Fig. 2 is a longitudinal vertical section and Fig. 3 a plan of an Arab
platen printing machine in which the guard is raised and lowered by a link
connection to a convenient moving part of the printing machine. Only so much
of the machine is shewn as is required to illustrate my invention.
In all the figures the same reference letter is used to indicate the same or
corresponding parts.
a indicates one of the side frames of the machine, b is the second motion
driving shaft, c the so-called impression shaft, and d the platen lever rocking
shaft.
e is the platen plate hinged at f, and g is the form or bed plate containing
the type.
h is the table on which the sheets of paper are placed as they are withdrawn
by hand from the printing machine.
is the blanket tightening rod.
jis the guard, formed of a piece of sheet iron, and which to suit the machine
is of the shapes shewn in elevation in Figs. 1 and and in plan in Fig. 3. The
guard jis pivotted in bearings k, formed in the two side trailing bars 1; the
trailing bars being hinged or pivotted about the blanket tightening rod 2.
m m are distance pieces or bars, connecting the two trailing bars 1; and n is a
cross piece formed with pin ends fitting in the bearings k, and attached to the
'sheet iron guard j.
o in Fig. 1 is a tail piece or pieces, which may form part of the guard j, or
be separate pieces secured to the guard j.

page_text: The full lines shew the platen e close against the form g, and the guard j
tilted up, so as to throw back the hand of the attendant. The dotted lines shew
the platen e tilted away from the form g, when the guard j is down, with its
rear edge over the top edge of the platen plate. A's will be evident from the
figure, the tilting of the guard j upwards, is caused by the tail piece o catching
against the underside of the table h, as the platen e approaches the form g, and
the bars trail over the impression shaft in the same direction.
In Figs. 2 and 3, the guard j is formed without a tail piece, but the upper
edge of the guard is connected by pin joints to the side links ; which are hinged
at their lower ends on stud pins screwed into or formed as part of the pins fitted
in the ends of the platen rocking levers p. The side links o thus effect the rais-
ing and lowering of the guard j at the proper times from the platen rocking
levers p.
In the case of other types of platen printing machines other arrangements
may be adopted for raising the guard at the proper times, from some con-
venient and suitable moving part of the printing machine, that shewn in Fig. 1
being intended as an illustration of one mode of effecting this.
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 platen printing machines the use of a guard supported by a hinged con-
nection so that the herein named rear edge of the guard rests immediately over
and partakes of the reciprocating movement of the top edge of the platen plate
during that portion of the movement of the platen plate which leaves an open-
ing between the platen plate and the form or type plate for feeding and remov-
ing the sheets of paper, whilst during the remainder of the movement of the
platen plate that is whilst near to and in contact with the form or type plate the
guard is tilted so as to throw up and then draw down said rear edge of the guard.
2. In platen printing machines the construction of guard consisting of a plate
hinged towards one end in bearings in a trailing frame or trailing bars hinged
close to the top edge of the platen plate immediately over which the other
herein named rear edge of the guard plate rests whilst partaking of the recipro-
cating movement of the top edge of the platen plate together with means for
tilting up and down said edge of the guard plate both at their respective proper
times substantially as set forth.
3. In platen printing machines the construction of guard and means for
operating the same substantially as herein set forth and illustrated in the
accompanying drawings.
Dated this 12th day of September 1900.
J. CLARK JEFFERSON,
30, Park Row, Leeds, Agent for Applicant.