prin
Year: 1899

page_text: 1, MAXIMILIAN THOMAS BARBER, of 37, Fountain Street, Manchester, Printer,
do hereby declare the nature of this invention to be as follows:-
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My said invention relates to improvements in guards for platen printing
machines.
In its essential features it consists of a cross bar or bars mounted on one or
more uprights at the sides or in front of the platen which deriving motion from
the platen or other parts of the machine act as risers or plungers to elevate or
depress the guard or guards so that as the platen advances to the type bed the
guard rises and lifting away the hand of the operator prevents it from being
trapped against the type. As the platen returns for the reception of fresh
printing material the guard is lowered out of the way.
In one form of my said invention the guard or guards is or are hinged to their
carriers so that they may lift on their return stroke in case the hand of the
operator may lie between the guard and the top of the platen and thus accidents
from the guard itself may be prevented.
In another form of my said invention the guard or guard bars are provided with
spiral or other springs or detents which act as cushions or buffers so as to press
the guard bar or bars down with moderate pressure when in their normal working
state while allowing them to rise in or on their supports in the event of any
obstacle intervening between the guard bar and the edge of the platen while
the latter is retreating from the type.
In some cases I combine with the guard or guard bars a fender or apron extend-
ing from the guard bar or bars below the front edge of the platen so that as the
guard bar rises the space between it and the edge of the platen is masked and
thus the operator cannot insert his hand while the guard is up.
נזי
11
11:1
عمل
SAL. 1900
E. T. WHITELOW, A.M. Inst. C.E.,
70, Deansgate, Manchester, Agent for the Applicant.

page_text: to be performed to be particularly described and ascertained in and by the
following statement:--
My said invention relates to improvements in guards for platen printing
machines as hereinafter described with reference to the accompanying drawings
to which reference is herein made.
In the said drawings
Fig. 1 is a side elevation showing the guard depressed clear of the platen.
Fig. 2 is a side elevation showing the guard elevated when the platen is in
contact with the type bed.
Fig. 3 is a front elevation of the fender or apron hereinafter described.
In Figures 1 and 2 the main frame A carrying the type bed at B, and the
oscillating platen Care indicated by dotted lines. In many types of platen
printing machine the platen is partly operated by side levers D and arms D
driven by suitable gearing from the main driving shaft A 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
à convenient source from which to operate the guard.
At the side of the platen is a lever which acts as a carrier for the guard.
The lever is fulcrumed at 1 to a spur or projection 2 rigidly attached at about
right angles to the boss of the armi D which carries the platen. The lever b
is connected with the side arm D by a link hinged at 6 and at b to brackets
fixed on the lever 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 guarde 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 11 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 partakes of this change of direction with the result that
the lever is lifted and owing to the restraint of the link it is caused to turn
about its fulcrum with the result that the guard e traverses approximately the
path indicated by the dotted line 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 understood
that the parts may be symmetrically arranged on the other side.
If the guard e is rigidly connected to the lever 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.
To prevent such accidents I according to one form of my said invention mount
the transverse guard bar e in the carriers or levers in such a manner that while
rigid and capable of resisting a downward pressure it may be non rigid or
capable of yielding upwards.
To this end the ends of the guard are so constructed as to be capable of
sliding on the ends of the levers and are pressed downwards against fixed stops
or collars by springs which can yield and allow the bar to slide upwards in
the event of the operator's hand being trapped between the guard and the
platen.
In another form of my said invention an apron or fender d is attached to the

page_text: guard c. The said fender is made sufficiently deep to mask the space between
the guard bar and the edge of the raised platen and so prevent access to the edge
of the platen except when the guard e has descended below the front edge. The
apron or fender d is preferably made of sheet metal and is bent to such shape or
set at such an angle as will enable it to clear the edge of the feed table when
rising. The particular shape and size of this part will depend on the particular
type of platen machine to which it may be applied and it may be applied either
to a yielding or non yielding transverse guard bar.
Although I have shown a particular method of operating the carriers from
the side arms D it is to be understood that the carriers may be operated from
any other convenient rotating or reciprocating part of the machine and in lieu
of the spiral metal springs shown in the drawings rubber or other springs may
be used for the like purpose.
I am aware that in such machines it has been proposed to use lifting guard bars
rising with the platen and I wish it to be understood that I herein make no
claim to lifting guard bars generally nor to anything described or claimed in the
Specification of Letters Patent No. 7 of A.D). 1899.
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:
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1. For preventing accidents in platen printing machines a guard carried by
carriers adapted to accompany the platen while rising and falling relatively
thereto so as to lie below the edge thereof when printing material is inserted to
rise above the platen when it approaches the type bed and so mounted on the
carriers as to be normally pressed down against fixed stops or collars by springs
while capable of yielding upwards to pressure applied to the underside sub-
stantially as set forth..
2. In a platen printing machine the combination with a transverse guard bar
rising and falling relatively to the edges of the platen of a fender or apron of such
a depth as to effectively mask the opening between the front edge of the platen and
the guard bar when the latter is raised above the front edge of the platen sub-
stantially as set forth.
Dated this 6th day of February. 1900.
E. T. WHITELOW, A.M. Inst. C.E.,
70, Deansgate, Manchester, Agent for the Applicant.