Title of Invention

AN AUTOMATIC SAMPLE POLISHING MACHINE FOR PREPARATION OF SAMPLE SURFACE FOR ANALYSIS

Abstract An automatic sample polishing machine for preparation of sample surface for analysis, comprising a programmable manipulator arm (1) driven by a stepper motor (3) capable of rotating about its axis; a first pneumatic cylinder (2) mounted at a distal end of the arm; a gripper (5) at the end of an actuator connected to said first cylinder, for holding said sample to be polished and a second pneumatic cylinder (20 extending with an actuator reaction pin fastened at the end of said second cylinder for holding said arm rigid; said actuator acting as an interlock for firing predetermined pulses from said stepper motor for bringing said gripper with sample to approach a grinding wheel for polishing.
Full Text FIELD OF APPLICATION
The present invention relates to an automatic sample polishing machine for
preparation of sample surface for analysis of its composition by optical emission
and X-Ray fluorescence spectrometry.
BACKGROUND OF THE INVENTION
With the advent of the present technical era, the need for laboratory automation
in steel plants is indispensable for achieving consistency and optimum cycle
timing for sample preparation, human safety etc. Laboratories are using high
technology such as spectroscopic methods for analysing the composition of the
steel samples. This demands consistency and good surface quality of the steel
samples as an input to the machine. In most cases, manual methods of sample
preparation are generally followed.
During the conversion of iron to steel in the converter, samples are collected, in
the shape of loli-pops. These samples are put in cassettes and sent by
pneumatic pulse conveying to the rapid analysis laboratory. The sample is taken
out from the cassette and sent to the grinding polishing machine for preparation
of its surface. Tne prepared sample is then analysed for it composition by
optical emission and X-ray fluorescence spectrometry.

The time between receipt of a sample and giving back its composition results are
short, due to very short heat times, compared to the earlier steel smelting
process. The time between receipt of a sample and sending its composition
results are in seconds, as the smelter waits, to take further necessary action
based on the analysis research.
Automating the process of sample preparation will facilitate to achieve the
consistency, better surface quality, optimum cycle timing, etc. Moreover, it
opens a path for going to the entire laboratory automation.
As a first step towards laboratory automation the sample polishing process of a
steel plant can be automated.
SUMMARY OF THE INVENTION
The main object of the present invention is to achieve consistency in quality of
surface finish of the sample.
Another object is to achieve reduction in total cycle time.

Yet another object of the present invention is to ensure safety by achieving
reduction in human involvement in hazardous environment.
Still another object of the present invention is to provide an integrated program
for the preparation of steel samples.
The equipment is a PLC controlled manipulator designed to perform the
sequences below.
Hold(samples ->Move(»rm) —>Grind ->Cool ->ReGrind->Dry samples-> Home.
This equipment consists of an arm, magnetic gripper for holding samples, cooling
tank, air amplifier for drying the samples, rotating table and suction motor for
holding the grinding paper, etc.
The arm is considered to be the main part of the equipment. This arm rotates
about its own axis with the help of stepper motor and the various positions of
the arm such as

controlled by the "C" compatible PLC. Thus, it is very much possible to alter the
cycle timings, adjusting the pressure, changing the motion pattern, etc.,
depending upon the samples to be ground.

Thus the present invention provides an automatic sample polishing machine for
preparation of sample surface for analysis, comprising: a programmable
manipulator arm driven by a stepper motor capable of rotating about its axis; a
first pneumatic cylinder mounted at a distal end of the arm; a gripper at the end
of an actuator connected to said first cylinder, for holding said sample to be
polished; and a second pneumatic cylinder extending with an actuator reaction
pin fastened at the end of said second cylinder for holding said arm rigid; said
actuator acting as an interlock for firing predetermined pulses from said stepper
motor for bringing said gripper with said sample to approach a grinding wheel for
polishing.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The invention can now be explained with the help of the accompanying drawings
where
Figure 1 shows plan, elevation and side view of an automatic sample
polishing machine of the present invention.
Figure 2 gives details of marked portion XX of figure 1 showing a reaction
pin and a second pneumatic cylinder assembly.

DETAILED DESCRIPTION
As shown in Figure 1 an arm 1 is provided which is capable of rotating on its own
axis upto 360 degrees. The programmable manipulator arm 1 is driven by a
stepper motor 3, timing belt and a "C" compatible PLC ,
A first pneumatic cylinder 2 is mounted at the other end of the arm 1. A gripper
5 is fastened at the end of an actuator 1' for holding samples. The downward
movement of the actuator V causes the sample to approach the grinding wheel
(not shown). For this purpose a programmable logic controller PLC 6 is used.
The PLC 6 used is compatible with C language. A stepper motor 3 and the PLC 6
control the movement of the arm 1 to achieve various positions.
Figure 2 shows a reaction pin and a second pneumatic cylinder assembly 4.
The reaction piri\(also known as shot pin) is fastened at the end of the second
cylinder 2'. Extension of this actuator holds the arm 1 in its own position.
Retraction of the actuator releases the lock and now the arm can rotate. This
will act as an interlock for firing the predetermined pulses from the stepper
motor 3.

The gripper 5 consists of a magnet and this magnet is made to slide on a helical
groove. It facilitates the easy removal of samples after the grinding process is
completed.
A grinding motor is used for rotating a grinding wheel at 2800 rpm. A suction
motor is further used for holding grinding paper etc for polishing the sample.
A cooling tank is used for cooling the samples during the intermediate grinding
process. An air amplifier forces the cooled dry air on the samples.
The sequence of the process is described below:
i) A sample is brought to the magnetic gripper 5 of the equipment. This
can be done manually.
ii) Switch on the "START" button. Pressure selection switch available can
be used for handling the different kinds of samples i.e. hard/soft
samples.
iii) Interlocks checking is carried out such as emergency On/Off, proper
pressure in air line, lock / release of reaction pin (i.e. a small shot pin
is provided to take care of the reaction force generated by the arm
while grinding is being performed. On/Off of the grinding wheel, etc.

iv) Arm 1 reaches the extreme position of the grinding wheel.
v) Second pneumatic cylinder 2' extends with the shot pin and holds the arm 1
rigid.
vi) First pneumatic cylinder 2 extends to bring the contact between the sample
and the grinding wheel.
vii) First pneumatic cylinder retracts 2 after the preset time is completed.
viii) Second pneumatic cylinder 2' retracts to withdraw the shot pin and allow the
arm 1 to rotate.
ix) Arm 1 reaches the cooling tank. First pneumatic cylinder 2 extends with the
sample and gets cooled in water for a preset programmed time. Then the
cylinder is retracted upwards and out of the tank.
x) Arm 1 reaches the intermediate position of the grinding wheel. Second
pneumatic cylinder 2' extends and locks the arm 1. First pneumatic cylinder 2
extends and grinding is done.
xi) After the preset time is reached the first pneumatic cylinder 2 pulls-up. Then
second pneumatic cylinder 2' pulls the shot pin to unlock the arm.

xii) Arm 1 reaches at initial position and simultaneously an air amplifier starts
throwing air with force to dry the samples.
xiii) Now the sample is ready for analysis.
Interlock checks are to be carried out in the all the above mentioned sequence of
operation for ensuring safety and proper functioning of the equipment.
By using the stepper motor it is possible to precisely reach the positions on the
grinding wheel which results in optimum utilization of the grinding paper.
It is easy to modify the movements of the arm depending on the samples by
modifying the software codes. Cycle timings can also be easily modified.
As the magnetic gripper is made to slide on a helical groove, it facilitates the
easy removal of samples after the grinding process is completed.


WE CLAIM
1. An automatic sample polishing machine for preparation of sample surface
for analysis, comprising
- a programmable manipulator arm (1) driven by a stepper motor (3)
capable of rotating about its axis;
- a first pneumatic cylinder (2) mounted at a distal end of the arm;
- a gripper (5) at the end of an actuator connected to said first cylinder, for
holding said sample to be polished; and
- a second pneumatic cylinder (20 extending with an actuator reaction pin
fastened at the end of said second cylinder for holding said arm rigid;
characterized in that the said actuator acting as an interlock for firing
predetermined pulses from said stepper motor for bringing said gripper
with sample to approach a grinding wheel for polishing.

2. The sample polishing machine as claimed in claim 1, wherein a C-
compatible programmable logic controller (PLC) (6) with stepper motor (2)
are used to control the rotational movement of the arm through 270°
from initial loading position to the polishing point and the cooling tank.
3. The sample polishing machine as claimed in claim 1, wherein said second
cylinder (20 is for retracting to withdraw the actuator pin for releasing a
lock and allowing said arm (1) to rotate.
4. The sample polishing machine as claimed in claim 1, wherein said gripper
(5) comprises a magnet sliding on a helical groove for facilitating easy
removal of samples after grinding/polishing.

5. The sample polishing machine as claimed in claim 1, wherein said grinding
wheel is provided with a 2800 rpm motor.
6. The sample polishing machine as claimed in claim 5, wherein a suction
motor is additionally provided for holding grinding paper for polishing said
sample.
7. The sample polishing machine as claimed in claim 1, wherein said
programmable manipulator arm (1) is capable of rotating through 270° for
extending said arm to reach a cooling tank for cooling the polished
sample.
8. The sample polishing machine as claimed in claim 7, wherein an air
amplifier is used for throwing air with force for drying the polished
sample.
9. The sample polishing machine as claimed in claim 1, wherein the
movements of said arm and cycle timings for JIFfini it) samples can be
modified by suitably programming said PLC.

An automatic sample polishing machine for preparation of sample surface for
analysis, comprising a programmable manipulator arm (1) driven by a stepper
motor (3) capable of rotating about its axis; a first pneumatic cylinder (2)
mounted at a distal end of the arm; a gripper (5) at the end of an actuator
connected to said first cylinder, for holding said sample to be polished and a
second pneumatic cylinder (20 extending with an actuator reaction pin
fastened at the end of said second cylinder for holding said arm rigid; said
actuator acting as an interlock for firing predetermined pulses from said
stepper motor for bringing said gripper with sample to approach a grinding
wheel for polishing.

Documents:

00403-kol-2005-description provisional.pdf

00403-kol-2005-drawings.pdf

00403-kol-2005-form 1.pdf

00403-kol-2005-form 2.pdf

00403-kol-2005-form 3.pdf

403-KOL-2005-(05-12-2011)-FORM-27.pdf

403-kol-2005-granted-abstract.pdf

403-kol-2005-granted-claims.pdf

403-kol-2005-granted-correspondence.pdf

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

403-kol-2005-granted-drawings.pdf

403-kol-2005-granted-examination report.pdf

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

403-kol-2005-granted-form 13.pdf

403-kol-2005-granted-form 18.pdf

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

403-kol-2005-granted-form 3.pdf

403-kol-2005-granted-form 5.pdf

403-kol-2005-granted-reply to examination report.pdf

403-kol-2005-granted-specification.pdf


Patent Number 236143
Indian Patent Application Number 403/KOL/2005
PG Journal Number 40/2009
Publication Date 02-Oct-2009
Grant Date 30-Sep-2009
Date of Filing 13-May-2005
Name of Patentee TATA STEEL LIMITED
Applicant Address RESEARCH AND DEVELOPMENT AND SCIENTIFIC SERVICES DIVISION, JAMSHEDPUR
Inventors:
# Inventor's Name Inventor's Address
1 MITRA, FALGUNI TATA STEEL LIMITED., RESEARCH AND DEVELOPMENT AND SCIENTIFIC SERVICES DIVISION, JAMSHEDPUR 831001
2 GHOSH, BIBHAS TATA STEEL LIMITED., RESEARCH AND DEVELOPMENT AND SCIENTIFIC SERVICES DIVISION, JAMSHEDPUR 831001
3 RAMASWAMI, N TATA STEEL LIMITED., RESEARCH AND DEVELOPMENT AND SCIENTIFIC SERVICES DIVISION, JAMSHEDPUR 831001
PCT International Classification Number B24B 27/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA