Improvements in Sheet Metal Stamping or Drawing Presses.
Year: 1898

page_text: Improvements in Sheet Metal Stamping or Drawing Presses.
I, HUGO DUDECK, of 12, Hermann Strasse, Rixdorf, near Berlin, Germany,
Machine Manufacturer, do hereby declare the nature of my invention to be as
follows:-
My invention has reference to improvements in sheet metal stamping or draw-
ing presses and relates more especially to means for moderating the force of the
blow, exerted by excentrics or cams upon the stamping block and for adjust-
ing the stamping block. For the exact work of stamping presses a smooth
stroke and a quick and easy adjustment of the block is of the utmost importance.
According to my invention I provide two excentrics or cams upon the driving
shaft of the press, which periodically are brought into contact with the stamping
block and press it downwards. I interpose between the said cams and the
stamping block, rollers revolubly arranged upon upright links, the lower ends
of which are pivotally fastened to the upper end of the stamping block. I con-
nect the upper ends of the links by means of levers to a rocking shaft, upon
which is mounted a second lever, adapted to be engaged periodically by a third
cam arranged upon the main shaft. The two excentrics or cams, upon the main
shaft being rotated, periodically exert a pressure upon the aforesaid rollers. The
force of this transverse strain, acting tangentially to the point of application of
the excentrics, is now broken up into two components, represented by the links
and the levers, connecting the links to the rocking shaft, the function of this
latter is to periodically lift the stamping block after each stamping movement.
By the described arrangement the force of the blow upon the stamping block is
greatly lessened and a smooth and accurate down-stroke is attained.
In order to adjust the height of the stamping block, I provide a square thread
upon the inner circumference of the hollow stamping block. A cylindrical body,
being revolubly secured in the block head, to which the lower ends of the roller-
carrying links are pivotally attached, and being provided with a square thread
upon its circumference, engages the thread of the hollow stamping block. By
turning the cylindrical body the stamping block can then be raised or lowered
and is secured in the desired position by means of set screws.
Instead of using the threaded cylindrical body for varying the height of the
stamping block, I may employ a number of screw bolts revolubly secured either in
the block head or in the block, the screw end engaging the respective other part.
In this case a ring, revolubly secured in either the block head or in the block,
would have to be provided with circumferential teeth, which are adapted to mesh
with toothed wheels, arranged upon the heads of the screw bolts. The toothed
ring, upon being revolved, will then actuate all the screw bolts in the same sense,
thereby raising or lowering the stamping block.
Dated this 10th dev of October 1898
FRANZ
DICKMANN,
Agent for the Applicant.

page_text: improvements in Sheet Metal Stamping or Drawing Presses.
I, HUGO DUDECK, of 12, Hermann Strasse, Rixdorf, near Berlin, Germany,
Machine Manufacturer, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
-
This invention relates to sheet metal stamping or drawing presses or benches
with concentrically adjustable guides for the metal-strip-holders and pressure
cylinder mechanism independent of the same.
My invention has reference to improvements in sheet metal stamping or draw-
ing presses and relates more especially to means for moderating the force of the
blow, exerted by eccentrics or cams upon the stamping block and for adjust-
ing the stamping block. For the exact work of stamping presses a smooth
stroke and a quick and easy adjustment of the block is of the utmost importance.
According to my invention I provide two eccentrics or cams upon the driving
shaft of the press, which periodically are brought into contact with the stamping
block and press it downwards. I interpose between the said cams and the
stamping block, rollers revolubly arranged upon upright links, the lower ends
of which are pivotally fastened to the upper end of the stamping block. I con-
nect the upper ends of the links by means of levers to a rocking shaft, upon
which is mounted a second lever, adapted to be engaged periodically by a third
cam arranged upon the main shaft. The two eccentrics or cams, upon the muin
shaft being rotated, periodically exert a pressure upon the aforesaid rollers. The
force of this transverse strain, acting tangentially to the point of application of
the eccentrics, is now broken up into two components, represented by the links
and the levers, connecting the links to the rocking shaft the function of this
latter is to periodically lift the stamping block after each stamping movement.
By the described arrangement the force of the blow upon the stamping block is
greatly lessened and a smooth and accurate down-stroke is attained.
In order to adjust the height of the stamping block, I provide a square thread
upon the inner circumference of the hollow stamping block. A cylindrical body,
being revolubly secured in the block head, to which the lower ends of the roller-
carrying links are pivotally attached, and being provided with a square thread
upon its circumference, engages the thread of the hollow stamping block. By
turning the cylindrical body the stamping block can then be raised or lowered
and is secured in the desired position by means of set screws.
Instead of using the threaded cylindrical body for varying the height of the
stamping block, I may employ a number of screw bolts revolubly secured either in
the block head or in the block, the screw end engaging the respective other part.
In this case a ring, revolubly secured in either the block head or in the block,
would have to be provided with circumferential teeth, which are adapted to mesh
with toothed wheels, arranged upon the heads of the screw bolts.
The toothed ring, upon being revolved, will then actuate all the screw bolts
in the same sense, thereby raising or lowering the stamping block.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 shows a front view of the press;
Fig. a side view;
Fig. 3 a plan view of the details relating to this invention.
The improved arrangement represented in Figs. 1 to 3 of the accompanying
drawings is designed not only with a view to enabling the guide of the metal-
strip-holder in a drawing machine or bench to be adjusted in a perfectly uniform
manner as the operation proceeds, but it furthermore affords this material advan-

page_text: tage over other similar apparatus, that any transmission of the strokes, imparted
to the pressure cylinders by the eccentric discs or cams, to the strip-holder-
guide, is entirely avoided.
These advantages, which are of the utmost importance to the neat and precise
production of stamped and cut out articles, are secured, in the first place, by the
arrangement, in the upper part of the strip-holder-guide a (Fig. 1), of a ring b
(Fig. 1), provided with any suitable screw thread, and revolvable in the pressure
plate d of the bench; which ring, on being turned by means of a proper key, so
as to vary its relative position to the adjusting holes c, causes the strip-holder-
guide a to perform a corresponding upward or downward movement; the position
of the parts, thus brought about, being then secured by means of set screws ce
(Fig. 2).
It will readily be seen that this adjustment, whilst it takes but little time to
be effected, enables, on the other hand, the parts to be set with a degree of accu-
racy which has been simply inconceivable in arrangements of this class as
hitherto constructed.
In order to protect the strip holder guide from the stroke or impact of the
cams ff (Figs. 1, 2 and 3), actuating the pressure cylinders gg, the said cams f f
do not directly operate upon the guide but by means of an intermediate link or
lever which is articularly inserted between the pressure plate d and the
cylinders g, g while levers loose upon the shafts of the cylinders g g are firmly
secured on to small revoluble spindles k.
Accordingly, the moment the cams f f come into contact with the cylinders gg,
the pushing force, or impact, operating tangentially to the point of application
of power of the cams f f, divides into two components, represented by the
links h h and the two levers ii; whereby the strip-holder guide a is relieved
from any strain so completely as to be entirely precluded from performing a
movement that is either inaccurate or insecure.
An additional cam m (Fig. 1 to 3), through the medium of a pressure cylinder
which is attached to the lever mounted upon the shaft k, operates the levers ii,
also connected with the said shaft k; which levers act upon the rods hh,
connected with the pressure plate d, and thereby cause the strip holder guide a
to rise and fall.
Or instead of a ring b, there might be provided, for the equable adjustment of
the strip-holder-guide, a number of screw bolts such as have hitherto been
employed; in which case, however, all the screw bolts must be tightened at the
same time, an object which may be effected, also, by constructing the top part
of the ring b, not in the shape of a screw spindle but in that of a toothed wheel,
whereof the teeth engage with the correspondingly toothed recesses, or "nuts,"
of the screw bolts arranged concentrically with the said ring b. Where this
arrangement is adopted it is only necessary to turn the ring b in order to
effect the simultaneous adjustment of all the bolts.
nn are fast and loose pullies for receiving and transmitting motion to the
driving shaft on which is mounted the toothed gear wheel o intermeshing with
and actuating the gear wheel and thereby the shaft carrying the cams f f.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
-
1. In sheet metal stamping or drawing presses the construction and use of;-
A toothed or screw threaded ring, such as b, adjusted in a metal strip-holder
guide, such as a, of a lever press, and revolvable in a pressure plate, such as d,
combined with a pressure-cylinder-support which is arranged above such ring
and pivotally connected with the pressure plate d by means of links or rods, such
as hh, for the purpose of enabling the said strip-holder-guide a to be adjusted
in an uniform manner as the operation proceeds, and of avoiding the trans-

page_text: mission to the strip-holder-guide a of the impact of the eccentrics, or cams, such
as
The improved drawing press or bench for sheet metal provided with a
centrically adjustable guide for the metal-strip-holder, and a pressure cylinder
mechanism independent of the same constructed and arranged substantially as
and for the purpose set forth, and shown by the drawings.
Dated the 1st day of Apr.
WM. BROOKES & SON,
55 and 56, Chancery Lane, London,
Agents for the Applicant.
WM. BROOKES & SON,
55 and 56, Chancery Lane, London,
Agents for the Applicant.