Improvements in Drawing, Stamping, and like Presses for Forming Articles from Sheet Metal.
Year: 1893

page_text: Date of Application, 29th Dec., 1893
Complete Specification Left, 29th Sept., 1894-Accepted, 8th Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in Drawing, Stamping, and like Presses for Forming
Articles from Sheet Metal.
We, TAYLOR AND CHALLEN LIMITED and STEPHEN WILLIAM CHALLEN,
both of Derwent Foundry, Constitution Hill, in the City of Birmingham,
Engineers, do hereby declare the nature of this invention to be as follows:-
This invention relates to the manner in which we construct and arrange a press
used for drawing, stamping, punching, and forming articles of sheet metal, whereby
we are enabled to arrange the toggle levers in a convenient manner and to balance
the slides and blank holder upon or within the main framework of the machine.
In carrying our invention into effect when constructing a drawing press for
operating upon sheet steel, we mount the crank shaft in the upper portion of the frame-
work of the machine, in the usual ordinary manner, and we drive the same by gearing
preferably connected from fast and loose pulleys mounted on a shaft arranged
below the crank shaft; an intermediate shaft with gearing may be placed between
for transmitting the power at a reduced speed from the first or high speed shaft.
Upon the first motion shaft we preferably arrange our clutch controlling mechanism
as described in our Specification No. 22403 of 1892, the clutch being arranged to
act automatically dependent upon the stroke of the machine and the position of the
crank, or to work independently by hand at will. We mount preferably below
the crank shaft a system of toggle levers which we cause to turn upon spindles or
shafts passing from one side frame or standard to the other; these levers being
arranged in a peculiar manner and linked up to carry the moving slides of the press to
which the blank holder is attached. We cause the crank of the crank shaft to be
connected by its rod to a main or central slide which carries the punch or forming
tool, this central slide working freely in guides formed upon the moving slides
coupled up to the toggle or elbow levers.
We form the upper members of our toggle lever system with projecting eyes or
bosses for carrying pins or rollers on to which lifting plates may engage for the
purpose of opening the toggles when the main slide is being lifted up by the con-
necting rod on the upstroke of the crank, and we cause these lifting plates to be
formed with hook like ends for permitting the rollers or pins to be engaged, while
the plain portion of the lifting plates we make to force out the toggle levers upon
the down motion of the crank and to keep the blank holder firmly in position
upon the plate or sheet of metal which is to be operated upon for the purpose of
preventing puckering of the metal when the punch or former presses upon it; the
downward motion of the toggle levers being completed before the punch or former
commences to operate upon the metal beneath the blank holder.
We balance the moving slides and blank holder of our press by means of a weight
or weights which we cause to slide within the outside framework of the machine
specially formed to receive them or we arrange vertical rods or bars upon the
framework to enable the weights to slide freely when the standards or frames have
not been specially prepared to receive them. We connect the moving slides to the
moving balance weights by means of chains passing over pulleys carried upon the
way shaft or shafts of our press, the pulleys revolving freely upon the shafts and
kept in position by loose collars or by other ordinary means. In order to permit of
the balance weight taking the true differential movement of the two independent
moving members within the framework viz. the main slide and the blank holder
and its slides, we mount a lever or pulley or system of levers or pulleys upon the
frames to one or all of which we connect the balance weight chain attachment, the

page_text: point of attachment being adjusted upon the fulcrumined lever or levers or pulleys
to suit the increased stroke of the main slide beyond that of the blank holder.
Sometimes instead of employing our sliding balance weight to balance both the
blank holder and the main slide we employ a weighted driving wheel to balance the
main slide and allow the weights and connecting levers and pulleys as before
described to be used for balancing the blank holder and its connections.
We construct our balance weight in the form of a plain casting or we employ a
series of weights to be connected to a main crosshead bar running upon each side
of the framework of the machine, the weights being thus capable of adjustment to
suit the actual requirement of the slide and blank holder.
We do not limit the application of our invention to any particular type of drawing
press, or to any particular material which is to be operated upon, but we modify
the essential features of our invention consisting of the improved combination of
toggle levers and lifting plates with the self contained system of balancing the
parts to suit any particular requirement.
Dated this 29th day of December 1892
MARKS & CLERK,
18, Southampton Buildings, London, W.C., Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Drawing, Stamping, and like Presses for Forming
Articles from Sheet Metal.
We, TAYLOR AND CHALLEN LIMITED and STEPHEN WILLIAM CHALLEN,
both of Derwent Foundry, Constitution Hill, in the City of Birmingham,
Engineers, do hereby declare the nature of this invention and in what manuer
the same is to be performed, to be particularly described and ascertained in and
by the following statement :-
This invention relates to the manner in which we construct and arrange a press
usad for drawing, stamping, punching, and forming articles of sheet metal, whereby
we are enabled to arrange the toggle levers in a convenient manner and to balance
the slides and blauk holder upon or within the main framework of the machine.
In the two accompanying sheets of explanatory drawings,
Figure 1 is a front elevation of our improved arrangement of press, and Figure 2
is a side elevation of the same.
Figure 3 is a sectional elevation showing the blank holder and punch down; and
Figure 4 is a similar view showing the punch and blank holder in its top or raised
position.
In carrying our invention into effect when constructing a drawing press for
operating upon sheet steel, we mount the crank shaft A in the upper portion of the
framework B of the machine, in the usual ordinary manner and we drive the same
by gearing CC with motion preferably communicated from fast and loose pulley D
mounted on a shaft E arranged below the crank shaft; an intermediate shaft e with
gearing may be placed between for transmitting the power at a reduced speed from
the first or high speed shaft. Upon the first motion shaft we preferably arrange
our clutch controlling mechanism F as described in our Specification No. 22403 of
1892, the clutch being arranged to act automatically dependent upon the stroke of
the machine and the position of the crank, or to work independently by
haud at will. We mount preferably below the crank shaft a system of toggle
levers GG G2 G3 which we cause to turn upon spindles or shafts H passing from one
side frame or standard to the other, these levers being arranged in a peculiar manner
and linked up to carry the moving slides K of the press to which the blank
holder L is attached. We cause the crank a of the crank shaft A to be connected
by its rod A' to a main or central slide M which carries the punch or forming
tool N, this central slide M working freely in guides formed upon the moving
slides K coupled up to the toggle or elbow levers GG'.

page_text: We form the upper members G G³ of our toggle lever system with projecting
eyes, arms or bosses g² g³ for carrying pins or rollers g on to which lifting plates
may engage for the purpose of opening the toggles when the main slide M is being
lifted up by the connecting rod on the upstroke of the crank, and we cause these
lifting plates to be formed with hook like ends O' for permitting the rollers or
pins to be engaged, while the plain portion O2 of the lifting plates we make to
force out the toggle levers upon the down motion of the crank and to keep the
blank holder L firmly in position upon the plate or sheet of metal which is to be
operated upon for the purpose of preventing puckering of the metal when the
punch or former N presses upon it, the downward motion of the toggle
levers G G G G being completed before the punch or former commences to
operate upon the metal beneath the blank holder.
We balance the moving slides K aud blank holder L of our press by means of a
weight or weights P P which we cause to slide within the outside framework of
the machine which we sometimes specially form to receive them; or we arrange
vertical rods or bars upon the framework to enable the weights to slide freely
within or upon them when the standards or frames have not been specially prepared
to receive them. We connect the moving slides K to the moving balance
weights P P by means of chains R R' passing over pulleys S carried upon the way-
shatt or shafts H of our press, the pulleys revolving freely upon the shafts and
kept in position by loose collars or by other ordinary means.
We sometimes employ a weighted driving wheel to balance the main slide and
allow the weights and connecting levers and pulleys as before described to be used
for balancing the blank holder and its connections.
We construct our balance weight P in the form of a plain casting or we employ
a series of weights to be connected to a main crosshead bar p running upon
each side of the framework of the machine, the weights being thus capable of
adjustment to suit the actual requirement of the slide and blank holder.
We do not limit the application of our invention to any particular type of
drawing press, or to any particular material which is to be operated upon, but we
modify the essential features of our invention consisting of the improved com-
bination of toggle levers and lifting plates with the self contained system of
balancing the parts to suit any particular requirement.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. In a press for stamping, punching, drawing and forming articles from sheet
metal, the combination and arrangement of toggle levers lifting plates and
balance weights substantially as and for the purposes hereinbefore described and
as illustrated in the accompanying drawings.
2. The construction of toggle levers in or upon which projecting eyes, arms or
bosses are formed for carrying pins or rollers for enabling hook like arms or
ends of lifting plates to engage for the purpose of opening the toggle levers,
substantially as hereiubefore, described and as illustrated in the accompanying
drawings.
3. In a press in which toggle levers are employed to carry the blank holder
and slides, the arrangement of a lever such as a plate or plates or the like for
opening the toggles upon the upstroke and for closing the toggles upon the
down stroke of the press tool or former substantially as hereinbefore described
and as illustrated in the accompanying drawings.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents for the Applicants.