IMPROVEMENTS IN PUNCHING AND SHEARING AFFARATUS
Year: 1870

page_text: LETTERS PATENT to Robert Baird, of Greenock, in the County
of Renfrew, North Britain, Shipbuilder, for the Invention of
« IMPROVEMENTS IN PUNCHING AND SHEARING AFFARATUS.”
"
Sealed the 13th June 1871, and dated the 17th December 1870.
PROVISIONAL SPECIFICATION left by the said Robert Baird at the
Office of the Commissioners of Patents, with his Petition, on the
17th December 1870.
I, ROBERT BAIRD, of Greenock, in the County of Renfrew, North
Britain, Shipbuilder, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN PUNCHING AND SHEARING APPARATUS,” to be as follows,
that is to say-
i
This Invention has for its object the constructing of punching and
shearing apparatus so that the working strain may be better distributed
and sustained than in ordinary apparatus; and so that the apparatus
will not be so liable to get out of order. Also, when the improved apparatus
is arranged for punching, it is contrived to yield the greatest pressure ·
relatively to the power applied at the commencement of its action when
it has the entire thickness of the plate to resist it, instead of the pressure

page_text: increasing as the punch progresses through the plate as in ordinary
apparatus.
•
In one modification of the improved apparatus as adapted for
punching, the upper jaw down through which the punch works is
formed with or has fixed to it two cheeks extending upwards and
joined at the top by what will be herein-after termed the abutment,
and between these cheeks there are three movable picces, by whose
action between the abutment and the head of the punch holder tho
punch is forced downwards. The middle one of the three pieces is made
with one or two lever arms either to receive long lever handles, or to bo
connected by a screw spindle to the back of the jaws, the lever piece
being moved in the latter case by turning the screw spindle. The other
two movable pieces are simply interposed between the middle or lever
piece and the abutment and punch holder head in order to obtain a
rolling motion between the parts. The lever piece is formed with a
gradually varying diameter, so that as it is turned not only does its
'own centre move downwards but it also causes the lower interposed
piece to move somewhat further downwards.. The interposed pieces
roll in opposite directions, the upper one on the under side of the abut-
ment and the lower one on the top of the punch holder head, and the
surfaces of this head and of the abutment are inclined so as to still further
increase the downward motion of the punch holder which results from the
combined action of all the parts. The pressure acting on the punch
being for equal increments of power applied to the lever end or screw
spindle inversely as the corresponding spaces traversed by the punch;
any desirable variation of such pressure is obtainable by shaping the
contact surfaces to suit; thus, if the abutment and punch holder head
are shaped concavely, or either of them, the pressure will be greater at
first and will gradually diminish as the punch gets through the plate.
The lover pieco and interposed pieces are kept in position by pins working
in suitably shaped slots, the former in the pieces and the latter in the
cheeks, or vice versa; and slipping may be additionally prevented
by corrugating the acting surfaces, or by forming them with very
shallow rounded teeth. In some cases one of the interposed pieces may
be dispensed with.
2
In shearing apparatus the upper or movable cutter is fixed to a
holder corresponding to the punch holder in the arrangement herein:
before described the other parts remaining the same.

page_text: "
In another modification, suitable for either punching or shearing, there
are two lever pieces which without interposed pieces act between tho
abutment above and the tool holder head below, these parts being inclined
as described with reference to the first modification. The rolling action
between the parts is however retained. For forcing down the punch or
cutter the levers are moved together by means of a spindle with right and
left screw threads, so that their acting parts turning in opposite directions
roll on each other, and also on the abutment and tool holder head; and
the acting parts being formed with gradually increasing diameters their
turning causes the tool to descend.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said "Robert Baird in the Great Seal Patent Office
on the 16th June 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
BBARD, of Greenock, in the County of Renfrew, North Britain, Ship-
builder, send greeting. .
.
WHEREAS: Her most Excellent Majesty Queen Victoria by Her
Letters Patent, bearing date the Seventeenth day of December, in the year
of our Lord One thousand eight. hundred and seventy, in the thirty-
fourth year of Her reign, did, for Herself; Her heirs and successors, give
and grant unto me, the said Robert Baird, Her special licence, that I,
the said Robert Baird, my executors, administrators, and assigns, or
such others as I, the said Robert Baird, my executors, administrators,
and assigns, should at any time agree with, and no others, from time
to time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN PUNCHING AND SHEARING
Apparatus," upon the condition (amongst others) that I, the said Robert
Baird, my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly describo
and ascertain the nature of, the said Invention, and in what manner. tho
same was to be performed, and cause the same to be filed in the Great
Scal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent..

page_text: NOW KNOW YE, that I, the said Robert Baird, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement in writing, reference being had to the accompanying
Drawings, that is to say :—
My said Invention has for its object the constructing of punching and
shearing apparatus so that the working strain may be better distributed
and sustained than in ordinary apparatus, and so that the apparatus
will not be so liable to get out of order.
Also, when my improved apparatus is arranged for punching it is 1
contrived to yield the greatest pressure relatively to the power applied
at the commencement of its action when it has the entire thickness of
the plate to resist it, instead of the pressure increasing as the punch
progresses through the plate, as in ordinary apparatus.
And in order that my said Invention, and the manner of performing 1
the same may be properly understood, I hereunto append a Sheet of
explanatory Drawings, to be hicrein-after referred to and representing
examples of punching and shearing apparatus as made with my
improvements.
5
Figure 1 is a front view, and Figure 2 is a sectional side elevation 20
showing the apparatus arranged as a punching bear. The upper jaw 1
down through which the punch holder 2 works has formed with (or
may have fixed to) it two checks 3 extending upwards and joined at the
top; and between these cheeks there are three movable pieces 4, 5, 6,
by whoso action between an abutment piece 7 fixed in the top and the 2
head of the punch holder 2 the punch 8 is forced downwards. The middle
one 5 of the three pieces is made with one or two lever arms 9 either to
receive long lever handles or to be connected as shown by a screw
spindle 10 to a lug or arm 11 formed on the back of the jaws, the lever
picċe 5 as it may be termed, being moved by turning the screw 3
spindle 10. The screw spindle 10 is shown partly right-handed and
partly left-handed, and is screwed into nuts made with transverso journals
to swivel in forked eyes formed for them in the ends of the lever arm 9
and fixed arm 11. The screw spindle may however be formed with its
screw thread or threads all one way and working in a nut either in the 3
lever 9 or arm 11 and connected to the other by a swivel piece between
collars on it. The spindle is made with a squared end to receive a
wrench or hand lever for turning it by. The two remaining movable..

page_text: pieces 4, 6, are simply interposed between the middle or lever piece 5
and the abutment 7 and punch holder head 2, in order to obtain a rolling
motion between the parts. The lever piece 5 is formed with a gradually
varying diameter as shown, so that as it is turned not only does its own
centre move downwards but it also causes the lower interposed piece. 6
to move somewhat further downwards. The interposed 'pieces 4, 6, roll
in opposite directions, the upper one 4 on the under side of the abut-
ment 7 and the lower one 6 on the top of the punch holder head 2, and
the surfaces of this head 2 and of the abutment 7 are inclined so as to
still further increase the downward motion of the punch holder, which
results from the combined action of all the parts. The pressure acting
on the punch being for equal increments of power applied to the lever
end 9 or screw spindle 10 inversely as the corresponding spaces traversed
by the punch; any desirable variation of such pressure is obtainable by
shaping the contact surfaces to suit. Thus if the abutment 7 and punch
holder head 2 are shaped concavely as shown, or either of them, thỏ
pressure will be greater at first and will gradually diminish as the punch
gets through the plate. The lever piece 5 is kept from being displaced
by a pin in its centre working in short vertical slots in the cheeks 3; it has
also fixed in it two other pins 12, having antifriction rollers on them,
and which work in curved slots in upper and lower pairs of plates 18
inserted between the cheeks 3 and the pieces 4, 5,
6. The upper
plates 13 are fixed to upper parts of the cheeks 3, whilst the lower
plates 14 are fixed to the punch holder 2, and the effect due to the
pins 12 and slots in the plates is to lift the punch holder and punch up
again whenever the lever piece 9 is moved upwards after each stroke.
To prevent the various pieces from slipping out of their proper positions
relatively to each other narrow portions of their width at the sides are
formed with shallow teeth or corrugations, the middle parts being smooth,
as best seen in Figure 1.
וי
Figure 3 is a horizontal section, Figure, 4 a front elevation, and
Figure 5, a side elevation showing a shearing machine as made with my
improvements.
In Figure 4 the plates 18, 14, are supposed to be removed from the
front side of the pieces 4, 5, 6, as is also a plate 15, Figure 5, which is
bolted on as a cover instead of the main casting, being made with two-
cheeks 3. The upper cutter 16 is fixed to a slide 2 corresponding to the
punch holder in the punching bear, but the top of this and the under

page_text: sile of tho abutment 7 are made with straight instead of concave.
inclinations. The corrugations to prevent slipping of the picces 4, 5, 6,
are made on the parts of their circumferences towards the front, as it is.
better for the strain to act through their moro inward parts, its doing so
counteracting a tendency that shearing cutters usually have to yield
inwards. The middle piece 5 is represented as made with a plain lever:
end 9 to receive a long lever arm to be worked directly by hand. As
will be seen by comparing the three Figures 3, 4, 5, the body 17 of the
apparatus is disposed obliquely, so that long bars can be cut square across
the middle.
In other respects the parts are substantially the same as the corre-
sponding parts of the punching bear herein-before described.
It is an advantageous feature of the shearing apparatus that the rolling
action of the lower interposed pièce 6 causes its point of contact with
the head of the cutter slide 2 to as it were follow and keep continually
over the point of action of the cutters.
In another modification, suitable for either punching or shearing, but
shown as adapted for punching in side elevation in Figure 6, there are
two lever pieces 18, 19, which without interposed pieces act between the
abutment 7 above and the tool holder head 2 below, these parts being
'inclined as described with reference to the other modifications. The
'rolling action between the parts is however retained. For forcing down
the tool holder 2 the levers 18, 19, are moved together by means of a
spindle 10 with right and left. screw threads, so that their acting parts
turning in opposite directions roll on each other, and also on the abut-
ment 7 and tool holder head 2, and the acting parts being formed with
gradually increasing diameters, as shown, their turning causes the tool
to descend. Portions of the surfaces of the abutment 7 and tool holder
head 2, and of the levers where acting on those parts, are corrugated to
prevent slipping. The tool holder 2 is raised on the return stroke by a
means of a small lever 20, centred on a pin fixed across the checks 3 and
acted on by the lower lever piece 19 at its outer end, whilst its inner end
acts beneath a pin on the tool holder 2.
The appliance for lifting back the tool holder last described is of
course also applicable to the other modifications of my improved 3
apparatus.
A
Having thus particularly described my said Invention, and the manner.
in which the same is to be performed, I have to state that I do not restrict

page_text: myself to the precise details herein described or delineated, but that what
I believe to be novel and original, and claim as the Invention secured
to me by the herein-before in part recited Letters Patent is,-
1. The shaping and combining together of the parts whereby the
power is applied and modified in punching and shearing apparatus;
substantially in any of the improved modes herein described and
delineated.
In witness whereof, I, the said Robert Baird, have hereunto set
my hand and seal, this Fifteenth day of June, in the year of our
Lord One thousand eight hundred and seventy-one.
DADET DATDD
-
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
'
ROBERT BAIRD. (L.S.).