PORTABLE LIMIT SWITCH APPLICABLE TO ANYWHERE
FIELD OF THE INVENTION:
The present invention relates to a wireless limit switch. More particularly,
the present invention relates to a battery operated wireless limit switch to
control machine operation applicable for industrial use.
BACK GROUND OF THE INVENTION:
In any modern shop, sophisticated machines are installed by the
industrialist with an object to achieve higher productivity with less
manpower. Most of the machines have a provision of auto-control
mechanism in the mode of operation. The operator of these machines
have to keep watch on all the times during operation. When one operator
operating a plurality of machines and for stopping one

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particular machines for any reason or other, he has to rush a short distant
to stop the machine. During these period many incidents may occur like
accident of the operator due to his fast motion in a hurry, excess metal
cutting on the job etc. To stop such adversity, present invention emphasis
on installation of a portable limit switch so that the machine may stop
automatically after completion of job.
OBJECTS OF THE PRESENT INVENTION
It is therefore, an object of the present invention to propose a battery
operated limit switch to control machine operation which eliminates the
disadvantages of prior Art.
Another object of the present invention is to propose a battery operated
limit switch to control machine operation which help one operator to
operate and handle more than one machine in a shift.

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A further object of the present invention is to propose a battery operated
limit switch to control machine operation, which increase the productivity.
A still further object of the present invention is to propose a battery
operated limit switch to control machine operation, which reduces the
manpower utilization.
An yet further object of the present invention is to propose a battery
operated limit switch to control machine operation which reduces machine
idle time.
SUMMARY OF THE INVENTION:
A battery operated wireless limit switch can be placed anywhere (the
desire position) on the machine surface (magnetic material) with the help
of a magnetic base. When it is operated by an actuator, fixed on

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a moving carriage of a machine. The transmitter in that unit sends a signal
(start/stop) to the receiver connected with the control switch of that
machine. Thereafter, the machine starts or stops depending on the
requirement. No wire connections are required from limit switch to the
controller. The unit has its own to identify and operates accordingly so
that is does not interfere other similar receiver connected in other machine.
Where an operator gives long travel cut in the lathe, it takes many hours to
complete or an operator has to concentrate operation in other machines,
but with this gadget in hand, he can place the wireless switch on the
required position of the machine and the machine stops itself automatically
at that particular point after knocking the striker of the limit switch. The
receiver also flashes on indication to inform operator about the completion
of operation cycle.

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BRIEF DESCRIPTION OF THE ACCOMPANIED DRAWING:
Fig. 1 - Shows the schematic diagram of the lathe machine with limit
switch attachment on its surface bed.
Fig. 2 - Shows a schematic view of wireless receiver & signal generator
device.
Fig. 3 - Shows separately the schematic diagram of the limit switch.
DETAIL DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE
INVENTION
In Fig - 1 and 3, it shows a limited switch (B) is mounted on a battery
backed up radio frequency (433.9MHZ) operated transmitter module is
placed on bed of a lathe machine (L M). The limited switch (B) device
comprising a powerful magnetic base (A) which is placed on a metallic
surface of lathe machine as desired by the operator, a limit switch (B)
having a movable projected Jib (J P) which acts as actuator to ecite battery
operated PLC circuit of switching device and a wireless

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transmitter with antenna (C), when the limited switch (B) is operated on
R.P. signal is transmitted to receiver (D) through an antenna fixed with
receiver unit. The signal is then amplified and operates a relay to provide
potential free contact (close to operator open to operate) to interface with
control circuit (F) of a machine to stop or to start.
A Strieker (s) is provided with the tool post of the lathe machine (L M). At
the final point of operation the Strieker (s) hits the projected Jib (PJ) of the
switching device (L S) which in turn cut off power supply from main source
(E).
The operating range of the limited switch in the range of 15-20 meter rial
distance.

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WE CLAIM
1. A battery operated wireless limit switch (B) to control machine operation
com prises:-
- at least one battery back up radio frequency operated transmitter
module
- at least one small antenna (C)
- at least one powerful magnet (A) mounted at the base for fixing the unit
any where it is required to be fixed on a magnetic material
- at least one receiving (D) unit with antenna connected with control
switch of the machine
2. The process of operating the limit switch comprising:-

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- an R.F. signal is transmitted to sa receiver (D) through an antenna fixed
with receiver unit
- the signal is then amplified to operate a relay
- the relay provides potential free contact (close to operate or open to
operate) to interface with to stop or to start

3. The process of operating the limit switch as claimed in claim 2 wherein
the operating range is limited to 15 - 20 match arial distance
4. The wireless limit switch as claimed in claim 1 wherein each unit has it
own code to identify.

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5. The wireless limit switch as claimed in claim 1 wherein the receiver
flashes on indication to inform operator bout the completion of
operation cycle.
6. The battery operated wireless limit switch to control machine operation
as substantially described and illustrated herein with reference to
accompanying drawing.
7. The process of operating wireless limit switch as substantially operated
and illustrated herein with reference to accompanying drawings.
Dated this 5th day of June 2007

A battery operated wireless limit switch can be placed anywhere (the
desire position) on the machine surface (magnetic material) with the help
of a magnetic base. When it is operated by an actuator, fixed on a moving carriage of a machine. The transmitter in that unit sends a signal
(start/stop) to the receiver connected with the control switch of that
machine. Thereafter, the machine starts or stops depending on the
requirement. No wire connections are required from limit switch to the
controller. The unit has its own to identify and operates accordingly so
that is does not interfere other similar receiver connected in other machine.
Where an operator gives long travel cut in the lathe, it takes many hours to
complete or an operator has to concentrate operation in other machines,
but with this gadget in hand, he can place the wireless switch on the
required position of the machine and the machine stops itself automatically
at that particular point after knocking the striker of the limit switch. The
receiver also flashes on indication to inform operator about the completion
of operation cycle.