Improved Guard for Presses Used in the Stamping and Drawing of Sheet Metal.
Year: 1899

page_text: Date of Application, 9th Feb., 1899
Complete Specification Left, 9th Nov., 1899-Accepted, 9th Dec., 1899
PROVISIONAL SPECIFICATION,
Improved Guard for Presses Used in the Stamping and Drawing of
Sheet Metal.
We, WILLIAM ARTHUR CRABTREE and DAVID CRABTREE, both of Wrose Brow
Works, Windhill, Shipley, in the County of York, Machine Makers, and ALBERT
SHAW, of the same place, Manager, do hereby declare the nature of this invention
to be as follows, that is to say:-
It relates to the application of a guard for preventing accidents to the users or
operatives having charge of or working in connection with presses for stamping
and drawing sheet metal and consists in producing or constructing said guards
or devices and mounting same to operate in such a manner as to render it
almost impossible for said user or operatives to be seriously hurt, injured or
wounded by said machines however careless they may be.
As is well known the most dangerous parts of these machines are where the
dies" or cutting and drawing tools are brought together to act upon the sheet
metal usually held by the hands of the operative and it is to these parts of same for
which our invention is applicable.
In carrying our invention into effect we mount a grid-like guard (which may
be formed of woven wire or trellis work) upon sliding pieces operated by lever
arms to which they are appropriately coupled, said sliding pieces being so formed
that the guard they carry may be moved upon them to completely protect by
covering the front and if necessary the rear approaches to the "dies."
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The lever for operating the guard is pivotally mounted upon the machine's
framework or parts carried by same, so that by cam, tappet or other mechanism
dies as these
it may be arranged to withdraw the guards from covering the
latter are being separated from each other, while when they are being moved
to approach each other said guards are quickly brought into position forcing out
of their path any obstacle, as the hands of the workman, which may be too nearly
approaching the path in which the dies operate, thus said "dies" are well
guarded at the dangerous period of their actions but are free of access for the
workman at all other times.
To enable the guard not to interfere with the sheet metal being operated upon
it is made to pass closely over same, while to prevent it from striking the hands
of the operative so as to cause him pain we mount an appropriate india-rubber
or other soft material buffer on the front edges which will come into contact
with said operative.
Instead of mounting the guard upon slides it may be possible to mount it
directly upon the lever arm.
Qthe daw of Halvmary 1899.

page_text: Improved Guard for Presses Used in the Stamping and Drawing of
Sheet Metal.
We, WILLIAM ARTHUR CRABTREE and DAVID CRABTREE, both of Wrose Brow
Works, Windlill, Shipley, in the County of York, Machine Makers, and ALBERT
SHAW, of the same place, Manager, 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, that is to say: --
It relates to the application of a guard for preventing accidents to the users or
operatives having charge of or working in connection with presses for stamping
and drawing sheet metal and consists in producing or constructing said guards
or devices and mounting same to operate in such a manner as to render it
almost impossible for said users or operatives to be seriously hurt injured or
wounded by said machines however careless they may be.
As is well known the most dangerous parts of these machines are where the
"dies" or cutting and drawing tools are brought together to act upon the sheet
metal held by the hands of the operative and it is to these parts of same for
which our invention is applicable.
In order that our said invention may be readily understood, we have hereunto
appended sheets of drawings illustrative thereof, wherein;-
Figs. 1 and 2 are front and side elevations respectively of a sufficient portion
of a press for stamping sheet metal, to which our improved guard is applied.
Figs. 3 and 4 are also front and side views respectively of portions of a stamp-
ing press having our improved guard mounted. thereon, but illustrate a modifica-
tion in the construction of said guard.
Figs. 5 and 6 are similar views to Figs. 1 and 2 respectively, but show a further
modified form of our improved guard.
Similar letters and figures indicate similar parts throughout the several views.
In carrying our invention into effect, we mount a grid-like guard a (which
may be formed of woven wire or trellis work) to which is attached the india
rubber or other soft material buffer o, upon the sliding piece b, which is operated
by the lever arm c to which it is coupled as shown, a part of said sliding piece b
taking over the square shaft (though this may be of other shape than square
in cross section, or a shaft having a key-way cut therein in which takes a key or
feather formed on the sliding piece b may be used instead) mounted in the adjust-
able bearings so that on said sliding piece being moved by the lever arm c
said guard and its buffer o will be caused to travel across and cover the front,
and if necessary the rear (as shown in dotted lines Fig. 2) approaches to the
dies" m and n.
The lever e is pivotally mounted at e on the bracket f carried by the frame-
work A of the machine, and oscillatory motion is imparted thereto by the cam g
which operates it by means of the bowl o taking within the cam groove gl¹, said
cam being mounted on the shaft h, while the groove is so arranged on said
cam that it will cause the level e to withdraw the guard and its buffer from
covering the dies m and n as these latter are being separated from each other,
while when they are being moved to approach each other said guard and buffer
are quickly brought into position so that this latter forces out of its path any
obstacle, as the hands of the workman which may be too nearly approaching the
path in which the "dies m and operate, thus said "dies" are well guarded
at a dangerous period of their actions, but are free of access for the workman at
all other times.
"
F

page_text: To enable the guard not to interfere with the sheet metal being operated upon
it is made to pass over the same.
In the modified arrangement illustrated by Figs. 3 and 4, the guard a is
mounted on supplementary bearings in order that an extra guard y may be
mounted at the opposite side of the machine to that occupied by the guard a
so as to prevent the operative placing his hands between the dies m and n from
that end of the machine.
If desired we may dispense with the movable grid like guard a and mount the
buffer or guard only on the slide or p, and in conjunction with this arrange-
ment of parts a stationary guard might be used somewhat as shown at a Figs. 5
and 6. Further, said buffer or guard o may be mounted on the lever pivotted
at to bearings s and connected to the lever arm by the rod 1, said lever arm e
being oscillated at the proper time as herein before described by the cam g, or,
by so arranging the mounting of the cam and lever arm e, we may mount the
guard and its buffer o directly on said lever arm c.
From the foregoing description it will readily be seen that without departing
from the nature of our said invention, we may use other suitable means for causing
the guard or guards and its or their buffers to be moved or traversed at the requisite
times for the purposes hereinbefore described, as also make further alterations
in the construction of said guard or guards and its or their bearings.
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:-
An improved guard for machines of the class described, the same being con-
structed and arranged to operate or move substantially as herein specified.
Dated this 8th day of November 1899.
SAMUEL HEY,
Agent for Applicants.