Improvements in Power Presses for Drawing, Stamping, and the like purposes.
Year: 1899

page_text: Date of Application, 27th Apr., 1899
Complete Specification Left. 27th Jan., 1900-Accepted, 10th Mar., 1900
PROVISIONAL SPECIFICATION.
Improvements in Power Presses for Drawing, Stamping, and the like
purposes.
I, STEPHEN WILLIAM CHALLEN, of Derwent Foundry, Constitution Hill, in
the City of Birmingham, Engineer, do hereby declare the nature of this invention
to be as follows:-
This invention relates to improvements in power presses usually employed for
forming articles from sheet metal, by what is known as the drawing and stamping
process in which a "pressure plate" is used, but which may also be used for other
purposes in which a similar pressure plate, or its equivalent in the form of a die
&c. may be required.
Primarily the object of this my invention is to provide improved means whereby
the weight of the pressure plate, and the pressure plate holder or slide to which
it is attached and other parts connected thereto is balanced or carried, by a weight
with chains and pulleys &c., after the manner herein described; also improved
arrangement in combination, of toggle levers and their cams for operating the
aforesaid pressure plate holder.
A machine constructed broadly according to this my invention consists as
follows, that is to say:-The framework of the machine with its bearings, brackets
&c. is very much after the ordinary manner, except in so far as may be specially
required for these my improvements. A central punch slide is operated by a
connecting rod or rods from an upper crank shaft, and also a pressure plate slide
(holder) is suitably carried in the frame, which forms also the means for support-
ing the said central or forming slide. This pressure plate slide is carried by
means of a system of toggle levers at front and back of machine having their
fulcrum joints carried from the frame, and their lower ends connected up to the
pressure plate slide, and thus having their knee joints between their fulcrums
and the slide. These levers have each an upper free end or tail which is carried
over the crank shaft, so as to each engage with its own particular cam upon such
shaft; hence each toggle lever is operated independently of the others.
facilitates a more perfect construction in the configuration of the cams, rather than
if one broad cam operated both proximate levers.
This
Again; To the pressure slide connect (preferably one at the front and one
at the back) a chain which upwardly passes over pulleys which are conveniently
carried upon the weigh shafts, which form the fulcrum joint pins for the toggle
levers, and thence downwardly to depending rods whose upper ends are support-
ingly attached to a balance weight which surmounts the machine frame. This
weight is capable of a rising and falling movement, and is further controlled by
a slideway or slideways, and generally by having a central hole sliding freely upon
a central post upon the frame. Thus as the cams raise and straighten the toggle
levers, the pressure slide is lowered, which in its descent lifts the overhead balance
weight, and vice versa.
Dated this 26th day of April 1899
CHARLES T. POWELL,
Applicant's Agent.

page_text: Improvements in Power Fresses for Drawing, Stamping, and the like
purposes.
I, STEPHEN WILLIAM CHALLEN, of Derwent Foundry, Constitution Hill, in
the City of Birmingham, Engineer, 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:-
This invention relates to improvements in power presses usually employed for
forming articles from sheet metal, by what is known as the drawing and stamping
process in which a "pressure plate" is used, but which may also be used for other
purposes in which a similar pressure plate, or its equivalent in the form of a die
&c. may be required.
Primarily the object of this my invention is to provide improved means whereby
the weight of the pressure plate, and the pressure plate holder or slide to which
it is attached and other parts connected thereto is balanced or carried, by a weight
with chains and pulleys &c., after the manner herein described; also improved
arrangement in combination, of toggle levers and their cams for operating the
aforesaid pressure plate, holder.
In order to more clearly explain this my invention, I have appended hereunto
an illustrative drawing upon which are figures and numbers of reference, similar
numbers referring throughout the several views to the same thing or part.
Fig. 1, shows a front view of a machine constructed according to this my inven-
tion.
Fig. 2, is a part sectional view of the machine on line A-B, in which the
balance arrangement is shown.
Fig. 3, is a detail view showing the toggle lever arrangement.
Fig. 4, is a plan view of the toggle levers &c.
Fig. 5, is a detached front view of one of the depending rods for carrying the
balance weight.
A machine constructed broadly according to this my invention consists as
follows, that is to say-The framework 6, of the machine with its bearings,
brackets &c. is made very much after the ordinary manner, except in so far as
may be specially required for these my improvements. A central punch slide 7,
is operated by (a connecting rod or) rods 8, 8, from an upper crank shaft 9, and
also pressure plate slides 10, which is in most cases advantageously made in two
parts which are rigidly secured to each other by rods 30, 30, or other suitable
means. The slides 10, are suitably carried in the frame, which forms also the
means for guiding and supporting the said central or forming slide 7. These
pressure plate slides 10, are carried by means of a system of toggle levers 11, 12,
13 and 14, at front and back of machine having their fulcrum joints carried from
the frame, upon the weigh shafts 15 & 16, and their lower ends connected up
to the pressure plate slide by links 17 and 18, and thus having their knee joints 19
& 20 between their fulcrums and the slide. These levers have each an upper free
end or tail 21, 22, 23 & 24, which is carried over the crank shaft 9, upon which is
mounted the cams 25, 26, 27 and 28, so that each lever engages with its own
particular cam upon such shaft; hence each toggle lever is operated independently
of the others. This facilitates a more perfect construction in the configuration of
the cams, rather than if one broad cam operated both proximate levers. Each
cam is particularly shaped so as to simultaneously operate all four levers to effect
the raising and lowering, and pressure of the slide with its pressure plate, in a

page_text: perfectly equal manner. Each lever is also alike in construction, although occupy-
ing different positions, and thus simplifying construction.
Again. 29, is a bridge like bracket, carried from the two rods 30, 30, which
latter are again secured at their ends in the pressure plate slide 10. To this
bracket 29, are secured the ends of the chains 31, 31, by means of the rods 32, 32,
or other convenient device. These chains pass upwardly over pulleys 33, 33, which
are conveniently carried upon the weigh shafts 15 & 16, which form the fulcrum
joint pins for the toggle levers, and thence downwardly to depending rods 34 & 35,
whose upper ends are supportingly attached to a balance weight 36, which sur-
mounts the machine frame. This weight is capable of a rising and falling move-
ment, and is further controlled by a slideway or slideways, and generally by
having a central hole sliding freely upon a central post 37, which is secured upon
the frame. Thus as the cams raise and straighten the toggle levers, the pressure
slide is lowered, which in its descent lifts the overhead balance weight, and vice
versa. Although the use of two depending rods 32, 32, are very convenient,
I may in some cases use four, which probably would be more convenient in the
case of a single crank shaft machine.
Having now particularly described and ascertained the nature of this my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. In a power press the combination and arrangement of mechanism for operat-
ing the pressure plate slides comprising the four individual toggle levers with
their several cams, all as set forth and shown upon the drawings.
2. In a power press the combination and arrangement of means for balancing
the pressure plate slide comprising the overhead weight 36, controlled by guide
post 37, with depending rods 34, 35, pulleys 33, 33, and chains 31, 31, attached
to such slide, all as set forth and shown on the drawings.
Dated this 26th day of January 1900.
CHARLES T. POWELL,
Applicant's Agent,
158, Edmund Street, Birmingham,