IMPROVEMENTS IN TOOLS FOR SHEARING PUNCHING AND CLAMPING
Year: 1883

page_text: LETTERS PATENT to Thomas Perkins of Hitchin in the County of Hertford
and Samuel Gilbert Junior of Wansford in the County of Northampton for
an Invention of IMPROVEMENTS IN TOOLS FOR SHEARING PUNCHING AND
CLAMPING
"
PROVISIONAL SPECIFICATION left by the said Thomas Perkins and
Samuel Gilbert, Junior, at the Office of the Commissioners of Patents on
the 11th January 1883.
THOMAS PERKINS of Hitchin in the County of Hertford and SAMUEL GILBERT
Junior of Wansford in the County of Northampton. "IMPROVEMENTS IN TOOLS
FOR SHEARING, PUNCHING AND CLAMPING "
This invention has for its object improvements in tools for shearing punching
and clamping.
The tool I construct for shearing metal by manual labour consists of a cast iron
base with an upright web or flange and a head. On the left the head is connected
with the web; on the right is the fixed shear blade, it is attached at the back of
the web by screws.-The moveable shear blade is behind the fixed blade and is
arranged to turn about a stud projecting forward from the head. The head carries
a blade spring which pressing down upon the end of the moveable blade beyond the
fulcrum tends to raise its cutting part away from the fixed blade and to open the
shears. The head also carries a stud upon which a hand lever turns. The boss of
the hand lever is eccentric to the stud on which the lever turns and is immediately
over the cutting end of the moveable blade, in fact this part of the moveable blade
is held against the boss by the spring. On moving the hand lever from left to
right the eccentric boss operates to depress the cutting edge of the moveable blade
causing it to descend immediately behind the fixed edge. Any sheet or rod placed
between the blades is divided at this motion. On returning the hand lever moving
it from right to left the blades separate or open ready for another cut.
The projection in rear of the web on which the head is carried is so formed that.
in shearing sheet metal both parts of the sheet can pass freely away, the front
portion over the top of the web and the back portion beneath the projection.
Pin G21

page_text: In the punching tool the arrangement is similar, a lever carrying a punch
replacing the moveable blade and a bolster being provided upon the bed.
For clamping work upon a bench and for like purposes I employ also a hand
lever with an eccentric boss. The fulcrum of this lever is upon the upper end of a
stem which drops into a socket provided for it in the bench. The stem is forked to
receive the hand lever.
Also immediately beneath the hand lever a second or clamping lever is jointed in
the fork of the stem. The outer end or head of the clamping lever is globular and
a disc is carried loosely upon it. This disc when the tool is in use is placed upon
the work to be clamped down to the bench and then the hand lever being turned
over the clamping lever is depressed sufficiently to bring a powerful downward
pressure to bear upon the work. The stem enters the socket a greater or less
distance according to the thickness of the work and the friction in the socket is
sufficient to prevent the stem rising under the influence of the pressure.
In order to clamp work to a bench by the application of a pressure endwise a
tool is used provided with a hand lever having an eccentric boss; and this acts
against a clamping lever as already described.
Ji
Both levors are carried upon a base plate having a pair of studs on its underside.
The studs are received into holes on the face of the bench.

page_text: The Baldomas Ierkins and Samuel Cubert, Junior, in the Great Deal ratent
Cffice on the 11th July 1883.
THOMAS PERKINS of Hitchin in the County of Hertford and SAMUEL GILBERT
Junior of Wansford in the County of Northampton
"IMPROVEMENTS IN TOOLS
FOR SHEARING PUNCHING AND CLAMPING
"
This invention has for its object improvements in tools for shearing punching
and clamping.
The tool we construct for shearing metal by manual labour consists of a cast iron
base with an upright web or flange and a head. On the left the head is connected
with the web; on the right is the fixed shear blade, it is attached at the back of
the web by screws.
The moveable shear blade is behind the fixed blade and is arranged to turn about
a stud projecting forward from the head.
The head carries a blade spring which pressing down upon the end of the
moveable binde beyond the fulcrum tends to raise its cutting part away from tho
fixed blade and to open the shears. The head also carries a stud upon which a
hand lever turns. The boss of the hand lever is eccentric to the stud on which the
lever turns and is immediately over the cutting end of the moveable blade in fact
this part of the moveable blade is held against the boss by the spring.
On moving the hand lever from left to right the eccentric boss operates to
depress the cutting edge of the moveable blade causing it to descend immediately
behind the fixed edge.
Any sheet or rod placed between the blades is divided at this motion. On
returning the hand lever moving it from right to left the blades separate or open
ready for another cut.
The projection in rear of the web on which the head is carried is so formed that
in shearing sheet metal both parts of the sheet can pass freely away, the front
portion over the top of the web and the back portion beneath the projection.
In the punching tool the arrangement is similar, a lever carrying a punch
replacing the moveable blade and a bolster being provided upon the bed.
For clamping work upon a bench and for like purposes we employ also a band
lever with an eccentric boss.
The fulcrum of this lever is upon the upper end of a stem which drops into
a socket provided for it in the bench. The stem is forked to receive the hand
lever. Also immediately beneath the hand lever a second or clamping lover is
jointed in the fork of the stem. The outer end or head of the clamping lever
is globular and a disc is carried loosely upon it. This disc when the tool is in
use is placed upon the work to be clamped down to the bench and then the
hand lever being turned over the clamping lever is depressed sufficiently to bring
a powerful downward pressure to bear upon the work. The stem enters the
socket a greater or less distance according to the thickness of the work and the
friction in the socket is sufficient to prevent the stem rising under the influence
of the pressure.
In order to clamp work to a bench by the application of a pressure endwise a
tool is used provided with a hand lever having an eccentric boss and this acts
against a clamping lever as already described.
Both levers are carried upon a base plate having a pair of studs on its under side,
The studs are received into holos on the face of the bench.
In order that our said invention may be most fully understood and readily.
carried into effect we will proceed to describe the drawings hereunto annexed.

page_text: DESCRIPTION OF THE DRAWINGS
Figure 1 is a side elevation of a punching and shearing tool constructed according
to our invention. Figure 2 is a front elevation of the same. Figure 3 is a vertical
transverse section of the standard which carries the moving parts and stationary
cutters. This section is taken on the line 1. 1. in Figure 1. Figure 4 is an i
horizontal section taken on the line 2. 2. in Figure 1.
a is a base to be bolted down to any convenient support. b is a web or flange
cast with the base and also with a head c. d is the moveable shear blade, it is
mounted so as to be able to turn upon a stud e, fixed into the head. f is the
stationary shear blade, it is fixed by screws to the hinder face of the web b. The
head c is set back as is seen in Figures 2 and 3, so that the moveable cutter which
lies against the face of the head may pass behind the fixed cutter. g is a spring
fixed to the head and bearing upon the moveable cutter beyond the fulcrum, it
tends to raise the cutting part of the blado and to open the jaws of the shears.
h is a hand lever it is forged or fixed upon a stud or axis h¹ which is received into
a hole bored for it in the head. The end or boss of the hand lever is eccentric to
the stud and when the hand lever is thrown over from left to right (as seen in
Figure 1) the cutting end of the blade d is depressed and thereby the metal
between the blades, is cut. The junction of the head with the web which is to the
left side (as seen in Figure 1) is so formed that when shearing sheet metal the part
of the sheet divided and depressed by the moveable blade d, passes away clear
beneath the head and its connection with the web whilst the part of the sheet
which is sustained by the fixed cutter f, during the shearing operation passes clear
away in front of the head.
For the purpose of punching sheet metal a lever k is mounted upon the side of
the web b, in the same way as the moveable shear blade d, is mounted; it is
provided with a spring 1, tending to lift the end of the lever which carries the
punch, and there is a hand lever m, (similar to h) by which the lever k is depressed.
n, is the punch it is received into a socket at the extremity of the lever k, and is
secured by means of a clamping screw. o is a bolster corresponding to the punch
and supported beneath it by a projecting part of the web b, the form of the web at
this part is shown by Figure 4. p, is a guard fixed to the web b in such a position
ns to admit of the sheet to be punched being inserted between it and the bolster,
the punch descends through a hole in the guard and the guard serves to prevent
the sheet rising with the punch.
The Figures 5, 6, 7 and 8 show a variation in the construction of the tool; they
correspond respectively with the Figures 1, 2, 3 and 4. In the tool here shown
springs are dispensed with; they are replaced by links connecting the hand
levers and m, respectively with the blade and the lever upon which they operate.
99 are these links they are connected to the hand lever at the centro of curvature
of its boss or end and so keep the parts to which they are attached in contact in all
positions, rendering the application of springs unnecessary.
The Figures 9, shew separately the hand lever h.
Figure 10 is a side elevation and Figure 11, is a back elevation of our tool for
clamping work upon a bench.
The
7. is a stem which is received into a hole or socket provided for it in the bench;
it is forked at its upper end and serves as the fulcrum for two levers 8 and t.
lever s is a hand lever with eccentric end or boss and the lever t, is a clamping
lever. u is a disc connected with the end of the lever t, by a ball and socket
joint.
As already stated friction is sufficient to prevent the stem r, rising in the socket
in the bench, hence if the hand lever be drawn over whilst the disc u, is resting
upon a board or piece of work lying upon the bench the work becomes nipped and
clamped upon the bench.
Figure 12 is a plan and Figure 13 is a side elevation of the tool which wo

page_text: construct to clamp work by end pressure against a stop upon a bench. v is a base
plate provided on its under side with two studs to drop into holes provided for
them in the face of the bench. w is a hand lever with eccentric boss having its
fulcrum upon the base plate and x is another lever similarly mounted. The end
of the lever, is caused to abut against the end of the board or work to be clamped
and then by means of the hand lever the clamping lever is forced forward until
the work is firmly held.
SC
Having thus described the nature of our said Invention and the manner of
performing the same we would have it understood that we claim :-
"
First, Our improved shearing and punching tool substantially as described.
Second. The combination of a cutting blade moveable about a centre or fulcrum
and a hand lever with eccentric boss substantially as described.
Third. The combination of a lever moveable about a centre or fulcrum and
carrying a punch and a hand lever with eccentric boss substantially as described.
Fourth. Our improved tool for clamping work down to a bench or surface
substantially as described in respect to Figures 11 and 12.
Fifth. Our improved tool for clamping work endwise against a stop, sub-
stantially as described in respect to Figures 13 and 14.
In witness whereof I the said Thomas Perkins have hereunto set my hand
and seal this Ninth day of July in the year of our Lord One thousand
eight hundred and eighty three.