FIELD OF INVENTION
This invention relates to a device for shearing aluminium strips suitable for
production of electronic control panels.
BACKGROUND OF THE INVENTION
Control panels are manufactured in the form of large cubicles inside which
various electronic components are mounted and connected by wires to perform
logical functions for various control applications. For proper routing of wires
inside the cubicles, wire rack channels made of plastics are used. They are to be
mounted along with aluminum strips at the back of it for making them strong
and durable.
Aluminum strips are procured in standard lengths of about 5 meters and are cut
in the shop in short lengths according to the requirement inside the cubicle.
Cutting of strips is carried out using commercially available hand operated bench
mounted shearing machines. Cutting with this machine is to be done by exerting
a heavy force on the lever with one hand while holding the strip by the other. As
the cutting requirement is very large, the workmen finds it very difficult to cope
up with production. Moreover, they experience pain in hand as they are required
to exert heavy pressure on the lever to cut the strip. Also, when cutting is done
with the hand operated shear the cut edges are with burr which needs additional

de-burning process for such large number of cut pieces and it is also found that
the cut edge is not square.
Accordingly, there exists a need to overcome the disadvantages of the prior art.
OBJECTS OF THE INVENTION
It is therefore an object of the invention to propose a device for shearing
aluminium strips suitable for the production of electronic control panels which
eliminates the disadvantages of prior art.
Another object of the invention is to propose a device for shearing aluminium
strips suitable for the production of electronic control panels which eliminates
strain and fatigue of the operator caused by manual shearing process.
A still another object of the invention is to propose a device for shearing
aluminium strips suitable for the production of electronic control panels which
reduces cycle time of operation.
A further object of the invention is to propose a device for shearing aluminium
strips suitable for the production of electronic control panels which cuts the strips
without producing burrs on the cut edge avoiding subsequent de-burring
operation.
A still further object of the invention is to propose a device for shearing
aluminium strips suitable for the production of electronic control panels which
cuts with a square edge at the cut end of the strip.

SUMMARY OF THE INVENTION
Accordingly, a pneumatically operated shearing device (D) has been invented
and implemented in the panel assembly shop which can be used with ease even
by unskilled operators effortlessly. The device (D) is free from noise and also
compact in size making it suitable for use in an electronic shop environment. The
device (D) can be operated hydraulically also.
The present device (D) consists of a double acting pneumatic cylinder (1) having
a piston inside, capable of moving to and fro to move the lever (4). The lever (4)
moves the upper cutting blade (5) fixed on it, downwards to cut the strip (7)
against bottom cutting blade (6) fixed on a base support (11). The downward
movement of lever is provided by the piston of the cylinder (1) attached to the
lever (4) through fulcrum (12) and fulcrum (3) which joins the lever (4) with a
block (14) fixed on the base (11) of the shear head (A). The movement of piston
is actuated by a pneumatic pedal switch (8).
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Fig.l- shows the line diagram of the invented device
Fig.2- shows the line diagram of the shearing head

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE
INVENTION
As shown in fig.l and 2, the device (D) consists of a shearing head (A) having its
base rigidly fixed to a fabricated table (9) and a pedal switch (8) fixed at the
bottom of the table (9). The table has been designed to suitably place the shear
unit (A) at a convenient height for operation. The table (9) has been fabricated
with steel tubes to impart stability and strength to the unit. The shearing head
unit (A) consists of a Pneumatic cylinder having a piston inside it capable of
moving to and fro with the help of the pedal switch (8). The piston is attached to
a lever (4) by a fulcrum pin (12). The upper cutting blade or moving blade (5) is
fixed to the lever (4) at the position of cutting. The lever (4) is fixed to a block
(14) attached to the base (11) by another fulcrum pin (3). The bottom cutting
blade or fixed blade (6) is bolted (13) with base (11). Cutting blades are made of
hardened tool steel for having longer life. Cutting angles provided at the edge
enable to cut the material easily with no burr. The pneumatic cylinder (1) is
operated with compressed air, for example at 6 kg/sq cm. The Pneumatic
cylinder (1) is fixed to a back support (10) through a fulcrum pin (2). The back
support (10) is rigidly fixed to the base (11) of the shear head unit (A). When
the pneumatic pedal switch (8) is pressed by foot, the piston in the cylinder (1)
moves forward and this in turn swings the lever (4) carrying the moving blade
(5) to cut the strip. The construction enables to multiply the load produced by
the cylinder so as to cut the material with ease. The actuating pedal switch
directly works on mechanical principle of opening and closing the valves there by
no electricity is required to energize the device. The device (D) cuts the strips
when the pedal switch (8) is pressed and resets automatically once the pedal (8)
is released. The position of the job (7) is shown in fig.l and 2. The cutting
blades (5,6) have been designed to cut the material with a scissoring action to
avoid noise so that it can work in a delicate assembly shop. The blades (5,6) are
hardened and ground for providing sharpness and also to have burr-free cut

edges. The pneumatic pedal switch (8) has been incorporated for smooth
operation of the machine in such a way that the operator can use his leg to
operate the pedal switch (8) to actuate the machine to cut the aluminium strips
without any manual effort. The development cost of this device is also very
economical.

WE CLAIM
1. A device (D) for shearing aluminium strips suitable for production of
electronic control panels comprising;
a shearing head (A) having its base (11) rigidly fixed to a fabricated table (9),
the shearing head (A) comprising a pneumatic cylinder (1) having a piston
inside for actuating a lever (4), the cylinder being attached to a back support
(10) by a fulcrum pin (2), the said back support (10) being fixed with the
base (11) of the shearing head (A);
a lever (4) being fixed to the piston at one end by a fulcrum pin (12) and to a
block (14) by a fulcrum pin (3);
a block (14) being fixed to a base (11) of the shearing head (A);
a moving blade (5) being fixed to the lever (4) when a fixed blade (6) being
bolted (13) to the base (11) of the shearing head (A);
characterised in that the moving blade (5) is operated pneumatically through
pedal switch (8) so that aluminium strips are cut without manual effort.
2. The device (D) as claimed in claim 1 which cuts the said strips without
burrs so that subsequent de-burring operation is eliminated.

A device (D) for shearing aluminium strips suitable for production of electronic
control panel assembly consists of a shearing head (A) and a pneumatic padel
switch (8) to operate the head (A). The shearing head (A) is having a pneumatic
cylinder (1) inside which a piston works to actuate a lever (4). The cylinder is
attached to a back support (10) by a fulcrum pin (2). The back support (10) is
fixed with the base (11) of the shearing head (A). The lever (4) is fixed to the
piston at one end by a fulcrum pin (12) and to a block (14) by a fulcrum pin (3).
The block (14) is fixed to the base (11) of the shearing head (A). The whole unit
(A) is fixed rigidly with the top of a fabricated table (9). A moving blade (5) is
attached to the lever (4) when a fixed blade (6) is bolted to the base (11) of the
head (A). The moving blade (5) is operated pneumatically through the pedal
switch (8) so that aluminium strips are cut without manual effort.