FIELD OF APPLICATION
The present invention relates to a magnetic safety hanger for use in the working
area of an industrial plant, like for example a steel plant.
The magnetic safety hanger of the present invention is an innovative tool
developed for systeM-based safety of the persons working in the operating area
of mobile machines.
BACKGROUND OF THE INVENTION
The normal practice to ensure safety for working in the vicinity of moving
machines is as follows: -
a) The person who is the supervisor of the concerned area is informed about
the job in writing.
b) The operator of the machine is informed that the work is in progress in
the area of the machine which he is operating and that he is to take care.
Danger tapes and red flags are pasted around the area of work.
But if we look into the safety aspect of such arrangements these are ail man
dependent arrangements and chances of human error always prevail. If anyone
of these persons involved lose there alertness then the machine can hit the
person who is working in its operating area and if temporary ladders are used or
the working area is a confined space then the severity of the accident can touch
the limit.
SUMMARY OF THE INVENTION
The main object of the present invention therefore, is to provide a magnetic
safety hanger for ensuring system based safety and to eliminate or minimize
chances of human error while working in the operating area of moving machines.
This object can be achieved by stopping the moving machines by actuating the
limit switches with the help of a permanent magnet provided in the safety
hanger.
Magnetic safety hanger is a tool made of steel on which a strong permanent
magnet is fixed. This can be easily carried to different places in the work area
and mounted on a railing near the work area.
Thus the present invention provides a magnetic safety hanger made of
fabricated steel comprising a permanet magnet fixed therein for actuating
magnetic limit switches mounted on mobile machines when said mobile
machines move close to the working area where said magnetic safety hanger is
installed.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The invention can now be described with the help of the figures of the
accompanying drawings where
Fig. 1 shows conventional safety practice using danger
tape and red flag before starting the work.
Fig. 2 shows the stages of development of the magnetic
safety hanger of the present invention.
Fig. 3 shows the magnetic safety hanger of the present invention.
The magnetic safety hanger of the present invention can be used at a place
where work is to be carried out in the operating area of mobile machines like at
the bench level of coke oven batteries, walkway of crane gantry and other places
of similar type. The whole arrangement works in the following manner.
Magnetic limit switches are mounted on the mobile machine at both ends near
the railing in a manner so that they are In alignment with the magnetic safety
hanger when mounted on the railing. Before starting the work the magnetic
safety hanger can be placed on the railing and a trial taken. When machine
comes near the work area, the mangetic limit switch is actuated by the magnet.
Upon actuation of the limit switch the machine stops in accordance with the logic
provided without the intervention of any person. A message can also be
displayed on the operator screen indicating that persons are at work and the
machine cannot move in this direction any further, although the machine can
move away from the place. This whole arrangement ensures safety without
human intervention i.e. total system based safety.
6. The safety hanger as claimed in the preceding claims, wherein a display is
provided on the screen of the operator indicating that the machine cannot
move further because men are at work.
7. A magnetic safety hanger made of fabricated steel, substantially as herein
described and illustrated in the accompanying drawings.
WE CLAIM
1. A magnetic safety hanger made of fabricated steel, characterized in that
said magnetic hanger comprises a permanent magnet for actuating a
magnetic limit switch mounted on mobile machines for stopping the
mobile machines when said mobile machines move close to the working
area where said magnetic safety hanger is installed.
2. The safety hanger as claimed in claim 1, wherein said fabricated steel
structure is mountable on a railing near the working area.
3. The safety hanger as claimed in claim 1 or 2, wherein said safety hanger
is mounted such that it is in alignment with the magnetic limit switches
mounted said mobile machines.
4. The safety hanger as claimed in claim 3, wherein said limit switches are
mounted at both ends of said mobile machines.
5. The safety hanger as claimed in the preceding claims wherein appropriate
logic control is provided for stopping said mobile machines when they
move close to said safety hanger.
A magnetic safety hanger made of fabricated steel comprising a permanent
magnet fixed therein for actuating magnetic limit switches mounted on mobile
machines when said mobile machines move close to the working area where said
magnetic safety hanger is installed.