Improvements in Metal Shearing Machines.
Year: 1899

page_text: Date of Application, 5th Dec., 1899-Accepted, 24th Feb., 1900
Improvements in Metal Shearing Machines.
I, BRUNO WESSELMANN, of 1, Luisenplatz, Berlin, N.W., 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 of the
lever type, in which a movable blade is operated against a fixed cutter, as is
well understood.
In shearing machines having levers working on trunnions or pivots carried
laterally in a frame a great disadvantage exists in that the trunnions work but
one way and so the pressure gradually causes the trunnions to work loose or
have too much play.
This disadvantage soon shows itself when the shears are put to work the
working loose of the trunnions causing the blades to change their position rela-
tively to each other so that a faulty cut is performed and more power required
to operate the shears. These disadvantages are emphasised the thinner the sides
of the shear frame in which the trunnions are fixed and are especially apparent
in lever shears which have a rolled profile as with these rolled profiles there is a
tendency to make the frame and therefore the side carrying the levers as thin
as possible.
The object of my invention is to secure a strong and effective support of the
levers by providing a casting or suitably formed bracket which is fixed to the
frame so as to give an additional support or counter bearing to the heavily working
trunnions. The said casting or bracket also acts as a means of holding down the
plate whilst under the action of the shears and as a protecting piece or guard.
Our invention will be clearly understood from the following description and
annexed sheet of drawings.
In the said drawings.
Fig. 4 shows a front view of a lever shear constructed in accordance with my
invention, whilst Figs. 1 to 3 show the construction and arrangement of the cast-
ing or especially formed bracket which serves as the additional bearing or counter
support of the trunnions.
In carrying my invention into effect the frame a which may be of a rolled
profile is provided with a bracket c which may be cast or otherwise suitably
formed. The bracket c is so fashioned as to present a flat face d which is bolted
or otherwise suitably secured to the side b of the frame.
By the provision of the bracket c the trunnions g 1 of the levers find bearings
in or are furnished with points of support both in the side b and in the part c
which effectually relieves the one side of the entire strain.
Under this arrangement when pressure is applied the levers are so well sup-
ported that it is impossible for them to yield with their trunnions upwards or
downwards or even laterally so that a more reliable and exact working of the
blades is thus obtained. Even when cutting comparatively thick plates good
cutting results are obtained with the trunnions so supported.

page_text: The specially shaped piece or bracket c does not extend further down than is
indicated in Fig. 2, so that sufficient free space is left for moving the sheet to
be cut free between the blades.
The bracket c if made large enough may also serve as a guard or protector to
prevent the workman's hand from reaching the cutting point. It is also uesirable
that the bracket c should serve as a presser or holder down for the sheet to be
acted upon and to this end I propose to provide the said bracket with a pro-
jecting ridge or extension e.
If desired the specially shaped support or bracket c may be formed in one with
the side b.
The construction of the lever system ik may be varied without departing
from the spirit of my invention, the bracket c being so designed as to give an
additional bearing or counter support to the various trunnions.
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:
-
In metal shearing machines of the lever type a specially shaped support or
bracket c, e, firmly fixed or secured to the shear frame and with the part b
forming a double-sided support or bearing to the trunnions of the moveable
shear blade and levers the said bracket c also serving to hold down the sheet of
metal operated upon and acting as a protector substantially as described and
Dated this 4th day of December 1899.
For the Applicant,
E. K. DUTTON & Co.,
Chartered Patent Agents, 5, John Dalton Street, Manchester.