IMPROVEMENTS IN MACHINERY FOR FORGING, STAMPING, OR PRESSING AND PUNCHING METALS
Year: 1878

page_text: LETTERS PATENT to George Richard Postlethwaite, of the Firm of G. R.
Postlethwaite and Company, of Aston, near Birmingham, in the County of
Warwick, Mechanical Engineers, for the Invention of "IMPROVEMENTS IN
MACHINERY FOR FORGING, STAMPING, OR PRESSING AND PUNCHING
METALS."
Sealed the 9th May 1879, and dated the 22nd November 1878.
PROVISIONAL SPECIFICATION left by the said George Richard Postlethwaite
at the Office of the Commissioners of Patents on the 22nd November 1878.
GEORGE RICHARD POSTLETHWAITE, of the Firm of G. R. Postlethwaite and
Company, of Aston, near Birmingham, in the County of Warwick, Mechanical
Engineers. "IMPROVEMENTS IN MACHINERY FOR FORGING, STAMPING, OR PRESSING
AND PUNCHING METALS."
My Invention consists of the improvements hereinafter described in machinery
for forging, stamping, or pressing and punching metals, and my said Invention has
for its object to facilitate the throwing into and out of action of the ram or
compressor carrying the working tool without stopping the driving mechanism of
the machine.
My Invention is especially applicable to forging, stamping, and like machinery,
in which three machines are worked from the same rotating shaft, but for
convenience of description I will describe my Invention with reference to one
machine.
The principal or driving shaft of the machine carries a fly wheel, and is made to
rotate by being connected by means of toothed wheels or other gearing with a
steam engine or other prime mover. The said shaft has an excentric or crank,
having a throw equal to the length of the stroke to be given to the ram or com-
pressor, and consequently to the working tool of the machine. The said excentric has
a strong clip, to each side of the lower end of which the upper ends of two connect-
ing straps or plates are firmly secured. The lower ends of these connecting straps

page_text: have slots equal in length to the throw of the excentric. The head of the ram or
compressor fits between the lower ends of the connecting straps, and is connected
with them by a cross-pin fixed in the said head, the ends of the said pin taking into
the slots in the lower ends of the connecting straps. The compressor works or
slides in guideplates, in which it moves with sufficient tightness to be sustained in
any position to which it may be raised. The slots in the connecting straps are so
situated that on the ascent of the said connecting straps the ram or compressor is
raised to its highest position, but on the descending motion of the said straps the
slots of the said straps slide upon the ends of the pin in the head of the ram or
compressor, and the said ram or compressor remains in its raised position. Between
the connecting straps is a block of metal, which I will call a swing-block or distance
block. This swing-block is jointed to the connecting straps near its upper end. The
upper end of the swing-block, when it is in a line with the connecting straps, bears
against the lower end of the clip of the excentric, and its lower end bears on the
head of the ram or compressor. The length of the said swing block is such that
when the clip of the excentric is at its highest point it just fills the space between
the bottom of the said clip and the top of the ram or compressor, and thus establishes
a virtually rigid and uninterrupted connection between the clip of the excentric
and the ram or compressor. The upper and lower ends of the swing-block, as well
as the bottom of the clip of the excentric and the top of the ram or compressor, are
curved, the curves being struck from the centre on which the swing block turns.
When the swing block is in a line with the connecting straps, its curved ends are
seated firmly on seats of like curvature on the underside of the clip and top of the
ram or compressor respectively.
The said swing-block is provided with a spring, which when the said block is at
liberty to move, forces its lower end outwards from between the connecting straps.
When it is in this oblique position it no longer rigidly connects the clip of the
excentric with the ram or compressor, and the excentric rotates without actuating
the ram or compressor. By means of a handle the workman cau bring the swing-
block into a vertical position, in which case it rigidly connects the clip of the
excentric with the ram.
The action of the machine is as follows:-When the swing-block is in its normal
oblique position the ram or compressor is supported in its highest position, and any
adjustment of the tools or the introduction of the material to be operated upon may
be effected.
When it is wished to give motion to the ram or compressor the workman, by
pulling the handle described when the clip of the excentric is at its highest point,
brings the swing-block into a vertical position, when the rain or compressor performs
its ascending and descending motions on each rotation of the shaft. When it is
wished to arrest the motion of the ram the workman lets go the handle described,
when the spring of the swing-block forces the said block into an oblique position at
the moment when the clip of the excentric is at its highest point, and the ram is
brought to rest and is retained in its highest position.
I prefer to connect the working tool and the ram by means of a stalk on the
former taking into a socket or recess in the latter, a cushion of a slightly elastic
substance being introduced into the socket when a slightly yielding blow is
required.
Machinery constructed according to my Invention may be employed to operate
on metals in the form of sheets, strips, plates, bars, or blocks, and either in a hot or
cold state.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said George Richard Postlethwaite in the Great Seal Patent Office on the
12th May 1879.
GEORGE RICHARD POSTLETHWAITE, of the Firm of G. R. Postlethwaite and
Company, of Aston, near Birmingham, in the County of Warwick, Mechanical
Engineers. IMPROVEMENTS IN MACHINERY FOR FORGING, STAMPING, OR PRESSING
AND PUNCHING METALS."
"
My Invention consists of the improvements herein-after described in machinery
for forging, stamping, or pressing and punching metals, and my said Invention has
for its object to facilitate the throwing into and out of action of the ram or com-
pressor carrying the working tool without stopping the driving mechanism of the
machine.
My Invention is specially applicable to forging, stamping, and like machinery, in
which three machines are worked from the same rotating shaft, but for convenience
of description I will describe my Invention with reference to one machine.
The principal or driving shaft of the machine carries a fly wheel, and is made to
rotate by being connected by means of toothed wheels or other gearing with a steam
engine or other prime mover. The said shaft has au eccentric or crank having a
throw equal to the length of the stroke to be given to the ram or compressor and
consequently to the working tool of the machine. The said eccentric or crank has
a strong clip to each side of the lower end, of which the upper ends of two con-
necting straps or plates are firmly secured. The lower ends of these connecting
straps have slots equal in length to the throw of the eccentric or crank. The head
of the ram or compressor fits between the lower ends of the connecting straps, and
is connected with them by a cross pin fixed in the said head, the ends of the said
pin taking into the slots in the lower ends of the connecting straps. The ram or
compressor works or slides in guide plates, in which it moves with sufficient tight-
ness to be sustained in any position to which it may be raised. The slots in the
connecting straps are so situated that on the ascent of the said connecting straps the
ram or compressor is raised to its highest position, but on the descending motion
of the said straps the slots of the said straps slide upon the ends of the pin in the
head of the ram or compressor, and the said ram or compressor remains in its raised
position. Between the connecting straps is a block of metal, which I will call a
swing block or distance piece; this swing block is jointed to the connecting straps
near its upper end. The upper end of the swing block when it is in a line with the
connecting straps bears against the lower end of the clip of the eccentric, and its
lower end bears on the bead of the ram or compressor. The length of the said
swing block is such that when the clip of the eccentric is at its highest point it just
fills the space between the bottom of the said clip and the top of the ram or com-
pressor, and thus establishes a virtually rigid and uninterrupted connection between
the clip of the eccentric and the ram or compressor. The upper and lower ends of
the swing block, as well as the bottom of the clip of the eccentric and the top of the
rim or compressor, are curved, the curves being struck from the centre on which the
swing block turns. When the swing block is in a line with the connecting straps
its curved ends are seated firmly on seats of like curvature on the underside of the
clip and top of the ram or compressor respectively. The said swing block is provided
with a spring which, when the said block is at liberty to move, draws its lower
end outwards from between the connecting straps. When it is in this oblique
position it no longer rigidly connects the clip of the eccentric with the ram or com-
pressor, and the eccentric rotates without actuating the ram or compressor. By
means of a handle the workman can bring the swing block into a vertical position,
in which case it rigidly connects the clip or the eccentric with the ram.
I will now proceed to describe, with reference to the accompanying Drawing, the
manner in which my Invention is to be performed.

page_text: Figure 1 represents in front elevation a vertical forging or stamping machine
containing my improvements, the said machine being provided with three working
stamps arranged for a succession of blows or compressions.
Figure 2 is a vertical section of the machine taken on the line a, a, Figure 1, one
of the standards being omitted, and portions of the fly wheel and toothed wheel
being broken off. Figure 3 is a horizontal section of a portion of the machine
taken on the line b, b, Figure 2, the said Figure 3 being drawn to a larger scale than
Figures 1 and 2; Figure 4 represents the portion of the machine drawn to the same
scale as in Figures 1 and 2.
The same letters of reference indicate the same parts in Figures 1, 2, 3, and 4.
c is the driving shaft of the machine, having at its ends the fly wheels d, d; e is
a parallel shaft carrying three eccentrics, cams, or cranks, from which the three
stamps are worked.
The said shafte is driven from the driving shaft c by pinions
(one of which is marked g) on the latter shaft, gearing with toothed wheels f, f, on
the former shaft. As the mechanism situated between the eccentric cam or crank
on the shaft e and the ram or compressor is alike in each of the three stamp shown
in the Drawing I will only describe the mechanism in connection with one of the
said stamps.
h is a strong eccentric clip or head worked by the eccentric or crank on the
shaft e, the said eccentric or crank having a throw equal to the length of the stroke
to be given to the ram or compressor, and consequently to the working tool of the
stamp or machine. To each side of the lower end of the eccentric or crank clip h
two connecting straps or plates i, i, are secured; the lower ends of the said
connecting straps i, i, having slots k, k, in them equal to the length of the throw of
the eccentric or crank. The upper ends of the said connecting straps i, i, are fitted
into recesses at 1, 1, formed between ribs on the eccentric strap has represented.
The sides of the head m² of the ram or compressor m are cut away as best seen at
m³, m³, Figure 3, for the bottom parts of the connecting straps i, i, and guide pin n
to enter. The head m² of the ram or compressor m fits between the lower ends of
the connecting straps i, i, as represented in Figure 1, and is connected with them
by a cross pinn fixed in the said head m², the ends of the said pin n taking into
the slots,, in the lower ends of the said connecting straps. The ram or
compressor m slides in guide plates P, P, in which it moves with sufficient tightness
to be sustained in any position to which it may be raised. These slots k, k, in the
straps i, i, are so situated that on the ascent of the said straps through the action
of the eccentric clip and its eccentric or crank, the ram or compressor m is raised
to its highest position; but on the descending motion of the said straps the slots
k, k, in them slide upon the ends of the pin n, and the said ram or compressor
remains in its raised position in consequence of the action upon it of the guide
plates p, p, as before described; q is the swing block or distance piece situated
between the connecting straps i, i, and being jointed by the cross pin or centre to
the said straps near their upper ends. The said swing block or distance piece q can
either be brought into the same line as the straps i, i, as represented in Figure 1,
or be turned aside upon its joint pin r into the position represented in Figure 2:
When the said swing block is in a line with the straps i, i, its upper curved end q²
seats itself against the curved seat at the bottom of the eccentric clip h, and the
lower curved end q seats itself against the curved seat at m on the head of the
ram or compressor m. The said swing block q when in the position last described
completely fills up the space between the bottom of the clip and the head m² of
the ram or compressor m, and establishes a virtually rigid and uninterrupted
connection between the said clip h and the rau or compressor m, and on the
working of the machine; the said ram or compressor is raised and lowered like
an ordinary hammer or stamp. By means of the vulcanized india rubber spring t
(as seen in Figure 4) or other spring, the swing block 9 when at liberty to move
is made to take the oblique position represented in Figure 2, that is to say, its
unjointed end q³ is drawn outwards. When the swing block q is in this position
it no longer rigidly connects the clip with the ram or compressor m, and the

page_text: eccentric or crank on the shaft e rotates without actuating the said ram or com-
pressor m. The movement of the swing block q into its acting position is effected
by means of the handle u, see Figure 4, which is grasped by the workman during
the use of the machine.
g
The action of the machine is as follows:-When the swing block q is in its
normal oblique position, as represented in Figure 2, the ram or compressor m is
supported in. its highest position, and any adjustment of the tools or the intro-
duction of the material to be operated upon may be effected, the shaft e rotating
without affecting the ram or compressor m. When it is wished to give motion
to the ram or compressor m, the workman by operating upon the handle u when
the clip of the eccentric or crank is at its highest point brings the swing block
into a vertical position, when the ram or compressor m performs its ascending and
descending motions on each rotation of the shaft c. When it is wished to arrest
the motion of the ram or compressor m, the workman lets go the handle u when
the spring t of the swing block q raises the said block into an oblique position at
the moment when the clip of the eccentric or crank is at its highest point, and the
ram or compressor is brought to rest and retained in its highest position as before
described. Thus, the ram or compressor m is readily thrown into and out of action
by the workman without stopping the driving mechanism of the machine.
I prefer to connect the working tool and the ram by means of a stalk, on the
former taking into a socket or recess v in the latter, and fixed by means of a set
screw as represented in Figure 2, a cushion at of a slightly elastic substance
being introduced into the socket when a slightly yielding blow is required.
Although I have represented my Invention as applied to a machine provided
with three rams or compressors, yet my said Invention is also applicable to single
machines, or double machines, or to machines provided with more than three rams
or compressors.
The facility with which the ram or compressor can be thrown into and out of
action without stopping the machine permits machines containing my improve-
ments to be used for purposes for whichordin ary screw presses and drop hammers,
and stamping presses are now commonly used.
Machinery constructed according to my Invention may be employed to operate
on metals in the form of sheets, plates, bars, or blocks, and either in a hot or cold
state.
Having now described the nature of my Invention and the manner in which the
same is to be performed, I wish it to be understood that I claim as my Invention
of improvements in machinery for forging, stamping, or pressing and punching
metals, the construction and combination of parts herein before described and
illustrated in the accompanying Drawing for the throwing into and out of action of
the ram or compressor, carrying the working tool of the machine without stopping
the driving mechanism of the said machine, that is to say, the construction aud
combination of the swing block q, slotted connecting straps or plates i, i, and the
head m² of the ram or compressor m in conjunction with the guide plates p, p, for
supporting the ram or compressor when the swing block q is moved into an oblique
position, substantially as and for the purpose described and illustrated.
In witness whereof, I, the said George Richard Postlethwaite, have hereunto
set my hand and seal, this Eighth day of May, in the year of our Lord
One thousand eight hundred and seventy nine
Witness,
GEORGE SHAW.
GEORGE RICHARD POSTLETHWAITE. (L.S.)