Title of Invention

A DEVICE FOR DETECTING THE PRESENCE OF HOT STOCKS IN ROLLING MILLS OF STEEL AND METAL INDUSTRY

Abstract This invention relates to a device for detecting presence of hot stocks in for example, rolling mills in steel and metal industry, said device comprising: light capturing optics provided in a housing for capturing radiation from said hot stocks; an optical fibre conduit for carrying said radiation from hot stocks to a remote place; and an electronic circuitry arranged in said remote place for detecting presence of hot stocks from a high or low radiation signal received.
Full Text FIELD OF APPLICATION
The present invention relates to a device for detecting the presence of hot stocks
in rolling mills of steel and metal industry.
The detection electronics can be kept at a remote location from the hot metal.
Radiation from the hot stock can be carried to the detection electronics light
capturing optics at a remote location by optical fibre conduit.
The device of the present invention comprises light capturing optics, an optical
fibre conduit for carrying radiation from a hot stock to a far off place where the
detection electronics is provided, and detection electronics.
Thus the present invention provides a device for detecting presence of hot stocks
in for example, rolling mills in steel and metal industry, said device comprising:
light capturing optics provided in a housing for capturing radiation from said hot
stocks; an optical fibre conduit for carrying said radiation from hot stocks to a
remote place; and an electronic circuitry arranged in said remote place for
detecting presence of hot stocks from or low radiation signal received.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The present invention will now be described with the help of the accompanying
drawings where
Figure 1 shows light capturing optics of the present invention.
Figure 2 shows the sensor holder for connecting the optical fibre
conduit to a silicon photodiode.
Figure 3 shows a housing for the light capturing optics of Figure 1.
Figure 4 shows the design of the ferrule for optical fibre bundle end.
Figure 5 shows the detection electronics of the device.
DETAILED DESCRIPTION
The light capturing optics is shown in Figure 1 and Figure 3 shows the housing
for the light capturing optics of Figure 1.
Light capturing optics 1 consists of a biconvex lens 2 along with optical fibre
conduit 3 at the other end as shown in Figure 1. The specification of the lens 2
shown in Figure 1 can be of 23 mm diameter and 14 mm focal length. It can be
different depending on the application if specified by the user. The capturing
optics 1 focuses the light signal on the optical fibre conduit 3 which actually
carries it to the electronic signal detector. In this way the electronic circuitry is
shielded from the high temperatures of the hot stocks.
The optical fibre conduit 3 consists of a bundle of multimode optical fibre strands
(50 or more in number), 10 to 20 m long each depending on the length of optical
fibre conduit, enclosed in a spiral, flexible, mild steel hollow wire with plastic
sheath. The coating of the optical fibre strands is not removed which makes it
resistant against easy breakage.
The fibre bundling of multimode optical fibres of the present invention uses a
spiral, flexible, mild steel hollow wire with plastic sheath which is an economical
enclosure for optical fibre strands (50 or more in number). The method consists
of pulling out a copper wire inserted inside the spiral hollow wire enclosure and
attached to the bundle of optical fibre strands at one end. As the copper wire is
pulled out, the optical fibre strands are pulled inside the spiral hollow wire
casing. The ends of the optical fibre strands are then inserted inside ferrules
(Figure 4) and glued together using a heat resistant and waterproof standard
epoxy. The inclined ends are then polished flat using 5 µm polishing papers.
The optical fibre conduit 3 is connected to a silicon photodiode through a sensor
holder as shown in Figure 2 (sensor holder). The optical fibre conduit consists of
specially designed ferrules at both ends. The design of the ferrule is shown in
Figure 4. The dimension of the ferrule can be decided on the basis of the size of
fibre conduit and the number of fibre strands in the fibre conduit. This method
facilitates fabrication of the fibre bundles with the fibre strands as close as
possible at the extremities. Along the length of the conduit, the optical fibres are
splayed out which makes the arrangement flexible and liable to breakage.

The differentiator provides an edge detection (i.e. a pulse of 23ms duration)
whenever a change in the captured radiation has occurred between 1V/ms and
50V/ms. The differentiator is designed using the quad opamp IC like an
LM 324. The output of the differentiator is fed to a timer like an LM 555 in a
monostable configuration to generate a pulse. The edge detection output can be
accessed via a relay or an open collector configuration. A yellow LED gives an
indication of the output.
The LED bar graph driver connected to a LED bar graph which displays the
analog level. The analog level corresponding to the intensity of captured
radiation is also available.
The various outputs provided by the hot metal detector are level detection i.e. a
high or a low signal depending on the presence or absence of hot metal, edge
detection i.e. a pulse of 23ms duration whenever a change in the captured
radiation has occurred between 1V/ms and 50V/ms and LED bar graph which
displays the analog level. The analog output corresponding to the intensity of
radiation captured is also available. There is a 17pin connector (CN2 in Figure 5)
from which all outputs as mentioned above can be accessed.
The spectral response of the device is 350-1050nm. Its response time is 7µs for
analog output and 100µs for level detection and edge detection outputs.
WE CLAIM;
1. A device for detecting presence of hot stocks in plants like rolling mills of
steel and metal industry, characterized in that said device comprises :
- light capturing optics (1) provided in a housing for capturing radiation
from said hot stocks;
- an optical fibre conduit (3) for carrying said captured radiation from
hot stocks to a remote place; and
- an electronic circuitry (Fig.5) provided in said remote place for
detecting presence of hot stocks from a high or low radiation signal
received.
2. The device as claimed in claim 1, wherein said electronic circuitry is
provided with a comparator for detecting if the radiation signal received is
high or low, using a quad opamp IC.
3. The device as claimed in claim 1, wherein said electronic circuitry is
provided with a differentiator for providing edge detection output
wherever a change in the capture radiation signal has occurred
between 1 V/ms and 50 V/ms.
4. The device as claimed in claim 1, wherein said electronic circuitry is
provided with a driver connected to a LED bar graph for displaying
the analog level.
5. The device as claimed in claim 1, wherein said optical fibre conduit
comprises a bundle of multi mode optical fibre strands enclosed in a
spiral, flexible, mild steel hollow wire with plastic sheath.
6. The device as claimed in the preceding claims, said optical fibre
conduit is connected to a silicon photodiode through a sensor holder.
7. The device as claimed in claim 6, wherein said optical fibre conduit
comprises specially designed ferrules provided at the two ends of said
conduit.
8. The device as claimed in claim 7, wherein dimension of said ferrules can
be decided on the basis of the size of fibre conduit and the number of
optical fibre strands in the fibre conduit.
9. The device as claimed in claim 1, wherein the spectral response of said
device is 350 - 1050 nm and the response time is 7 µs for analog output
and 100 µs for level detection and edge detection output.
10. A device for detecting presence of hot stocks in for examples, rolling mills
in steel and metal industry, said device, substantially as herein described
and illustrated in the accompanying drawings.

This invention relates to a device for detecting presence of hot stocks in for
example, rolling mills in steel and metal industry, said device comprising: light
capturing optics provided in a housing for capturing radiation from said hot
stocks; an optical fibre conduit for carrying said radiation from hot stocks to a
remote place; and an electronic circuitry arranged in said remote place for
detecting presence of hot stocks from a high or low radiation signal received.

Documents:

00527-kol-2005-description provision.pdf

00527-kol-2005-drawings.pdf

00527-kol-2005-form 1.pdf

00527-kol-2005-form 2.pdf

00527-kol-2005-form 3.pdf

527-kol-2005-correspondence-1.1.pdf

527-kol-2005-correspondence.pdf

527-kol-2005-description (provisional).pdf

527-kol-2005-examination report-1.1.pdf

527-kol-2005-examination report.pdf

527-kol-2005-form 13-1.1.pdf

527-kol-2005-form 13.pdf

527-kol-2005-form 18-1.1.pdf

527-kol-2005-form 18.pdf

527-kol-2005-form 3-1.1.pdf

527-kol-2005-form 3.pdf

527-kol-2005-form 5-1.1.pdf

527-kol-2005-form 5.pdf

527-kol-2005-gpa.pdf

527-kol-2005-granted-abstract.pdf

527-kol-2005-granted-claims.pdf

527-kol-2005-granted-description (complete)-1.1.pdf

527-kol-2005-granted-description (complete).pdf

527-kol-2005-granted-drawings.pdf

527-kol-2005-granted-form 1.pdf

527-kol-2005-granted-form 2.pdf

527-kol-2005-granted-letter patent.pdf

527-kol-2005-granted-specification.pdf

527-kol-2005-others-1.1.pdf

527-kol-2005-others.pdf

527-kol-2005-reply to examination report-1.1.pdf

527-kol-2005-reply to examination report.pdf


Patent Number 246602
Indian Patent Application Number 527/KOL/2005
PG Journal Number 10/2011
Publication Date 11-Mar-2011
Grant Date 07-Mar-2011
Date of Filing 17-Jun-2005
Name of Patentee TATA STEEL LIMITED
Applicant Address AUTOMATION DIVISION, JAMSHEDPUR
Inventors:
# Inventor's Name Inventor's Address
1 SAHA, P.K. TATA STEEL LIMITED, RESEARCH & DEVELOPMENT DIVISION JAMSHEDPUR-831 001
2 SAURABH, MAMGAIN TATA STEEL LIMITED, RESEARCH & DEVELOPMENT DIVISION JAMSHEDPUR-831 001
3 TRIPATHY, A.K. TATA STEEL LIMITED, RESEARCH & DEVELOPMENT DIVISION JAMSHEDPUR-831 001
4 JAYSHREE, P TATA STEEL LIMITED, RESEARCH & DEVELOPMENT DIVISION JAMSHEDPUR-831 001
PCT International Classification Number B21D 11/06
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA