Improvements in Metal Shearing Machines.
Year: 1897

page_text: Date of Application, 28th Sept., 1897-Accepted, 6th Nov., 1897
COMPLETE SPECIFICATION.
Improvements in Metal Shearing Machines.
I BRUNO. WESSELMANN, of 54 Friedlander Weg, Gottingen, in the Empire of
Germany, 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 and accompanying drawings.
My said invention relates to improvements in metal shearing machines in
which an improved shearing effect is attained by giving the moveable blade a
spiral form and imparting a rotative motion to the blade about its longitudinal
axis simultaneously as it passes the cutting edge of the fixed blade. Owing to
the spirally running course of the moveable blade, the blade in all its phases of
shearing, lies approximately at the same cutting angle to the fixed blade, by
which an equal cutting efficiency is attained at all points of the blade, whilst
at the same time the cut acts in a drawing manner on account of the rotation
of the blade, as the spiral cutting edge is drawn in a certain sense, past the
cutting edge of the fixed blade to such an extent that the spiral cutting edge is
longer than the edge of the stationary blade.
And in order that my said inventions may be fully understood I have attached
hereto a sheet of explanatory drawings to which I will now refer.
In the said drawings.
Fig. 1 is a front view and Fig. 2 a plan of the improved metal shearing
machine.
Fig. 3 is an end view showing the moveable blade in its raised position.
Fig. 4 is an end view with the moveable blade in its lowest position.
Fig. 5 is a front view of a modified form of shearing machine, having a blade
of higher pitch and showing another method of rotating the blade.
Το
The base of the shearing machine framing a carries the horizontal fixed blade b
against une cutting edge of which the blade c with cutting edge c¹ is actuated
so that it performs simultaneously a descending and rotative movement.
effect this each end of the horizontal axis of the blade is mounted to revolve in
head bearings d g.
To
The head turns on the bolt d', whilst the head g turns in the slide f during
the up and down motion of the blade c. In the arrangement shown in Figs. 1
to 4 the blade is operated by means of the lever h. This lever h when moved in
the direction of the arrow Fig. 3 rotates the blade c by means of the pawl k
which engages with a ratchet wheels secured on the axis of the blade c.
effect the simultaneous downward motion of the blade c on turning the lever in
the direction of the arrow, I secure a curved link to the lower part of the
lever h. The link is guided by a pin i fixed to the framing and lying in a
slot m in the link l.
The slot m is excentric relatively to the centre of the axis of the blade c,
therefore the slide f with the blade c will be pressed downwards until it reaches
its lowest position as shown in Fig. 4. When this position is reached the
cutting effected by the double movement of the blade has been completed.
On raising the lever h, the pawl k is drawn back over the ratchet wheels, and

page_text: another pawl o mounted on the framing at the other end of the blade engages
with the ratchet wheel fixed
P
on this end of the axis of the blade
and prevents rotation of the blade. The upward movement of the blade
is effected by the excentric slot m on the raising of the lever. The
cutting edge c¹ receives a spiral motion corresponding to the rotation
imparted to the blade e, consequently during the downward motion of the blade,
the cutting edge c¹ maintains the same angle of cut relatively to the cutting
edge 6 of the fixed plate b.
The shearing force is thus uniform during the whole shearing operation, and
owing to the drawing action of the cut obtained by the double movement of the
blade e the efficiency of the apparatus is essentially increased.
As shown in Fig. 5 the blade e may also be arranged spirally, about an axis u,
the lower end of which is mounted to revolve in a bearing head h, the extension
of the axis forming the lever for raising and lowering the axis.
In order to effect such a rotation of the axis or blade e that on the descent
the cutting edge c¹ will come against the cutting edge of the fixed blade, I
key a toothed wheel upon the axis gearing with a curved rack z which is
secured to the framing a of the machine. The radius of the curve of the rack
is struck from the centre of rotation of the head d, and the rack is so con-
structed that on the downward movement of the lever the rotation of the
axis is effected to such an extent as is necessary for the continued action of
the spiral cutting edge c¹ against the cutting edge 6. On reversing the action
of the lever h¹ a reverse motion of the spiral blade e is effected by the toothed
wheel and curved rack 2, so that the spiral blade is in an appropriate position
for commencing the next cut. The lever is provided with a bush to be grasped
by the hand thus permitting the free rotation of the axis u.
C
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 metal shearing machines of the indicated description forming the move-
able blade of a more or less spiral shape and imparting to the same a rotatory
motion about its longitudinal axis in addition to its up and down motion for
the purpose and in the manner substantially as described and shown.
2. The general arrangement construction and combination of parts comprising
the improved metal shearing machine substantially as described and illustrated
with reference to Figs. 1 to 4 of the drawings.
3. The general arrangement construction and combination of parts comprising
the modified form of metal shearing machine substantially as described and
illustrated with reference to Fig. 5 of the drawings.
Dated this 27th day of September 1897
Doted this 27th day of September 1897
For the Applicant,
E. K. DUTTON & Co.,
5 John Dalton Street, Manchester, Chartered Patent Agents.