FIELD OF THE INVENTION
The present invention generally relates to polishing of different sizes of
complex-curved turbo-machinery components especially 2-dimensional and 3-
dimensional closed or open impellers with varying number of vanes. More
particularly, it relates to an automatic polishing device for surface finishing of
complex-curved-profiled components of turbo-machinery. Furthermore, the
invention relates to a method of automatic polishing of complex-curved-
profiled components of turbo-machinery.
BACKGROUND OF THE INVENTION
One of the important turbo-machinery equipment is a compressor in which
the most critical and complex component is a 2-dimensional or 3-dimensional
impeller that is comprised of twisted integral vanes attached to hub and
shroud. As the compressors operate at very high speeds of tens of thousands
of rpm, the most significant factor in design and manufacture of compressors
is the efficiency of compressor which in turn depends on the efficiency of
turbo-machinery components such as impellers. The efficiency of turbo-
machinery component such as impeller in turn depends on its surface finish
and requires a smooth surface finish to minimize the frictional losses. As the
required surface finish cannot be achieved during the manufacturing process
of an a turbo-machinery component, it is achieved as a post-milling operation
through manual polishing means which is not only inconsistent but also time
consuming. Hence an automated device and method for polishing the turbo-
machinery component such as impellers, to achieve the required surface
finish, is proposed.
Polishing devices have been previously employed for polishing variety of
components but none of the devices have been employed for automatic

polishing of turbo-machinery components as proposed in the current
invention.
US patent 6261154 B1 describes an apparatus for finishing the surfaces of
workpieces that is particularly suitable for polishing the surfaces of metal
workpieces and the apparatus comprising of a toroidal tub; finishing media in
a toroidal tub; vibrating means for moving a media in the tub in a generally
revolving helical motion in the tub; means for positioning a workpiece to be
polished in a media and rotating the workpiece in a media about an axis that
is oblique to and does not intersect with the axis about which media revolves
and without moving the position of the workpiece with respect to said tub as
the workpiece rotates.
US patents 9017142 and 20140227944 A1 describe a finishing apparatus and
method for surface finishing workpieces where a tub is rotatable about
vertical axis and operable to hold and rotate abrasive media completely
submerged in water or other liquid. One or more manipulators, each
supporting a spindle operable for supporting and rotating a workpiece about
a spindle axis of the spindle with the workpiece at least partially submerged
in the abrasive media and operable for holding spindle axis normal to and
spaced apart from the vertical axis with the spindle horizontal in the tub
during the surface finishing process while the tub is rotating.
US patent 20070107217 A1 describes a method for surface blasting of
integrally bladed rotors that includes providing an integrally bladed rotor,
providing a vibratory grinding System, arranging the integrally bladed rotor in
a grinding container of the vibratory grinding system, filling the grinding
container of the vibratory grinding system with blasting balls and operating
the vibratory grinding system filled with the blasting balls and the integrally
bladed rotor to accelerate the blasting balls, wherein the accelerated blasting

balls simultaneously strengthen the integrally bladed rotor on the surfaces of
all the rotor blades and in the annular space between neighboring rotor
blades.
US patent 20130273816 A1 discloses an invention of an automatic polishing
device and the method of using a device for the surface finishing of a
workpiece such as complex-curved-profile parts. Automatic polishing is
performed by mounting the workpiece on an apparatus which enables
different orientations along multiple axes and immerging the workpiece in a
controlled flow of abrasive slurry.
The present invention relates to a device and method for automatic polishing
of different sizes of complex-curved turbo-machinery components especially
2-dimensional and 3-dimensional closed or open impellers with varying
number of vanes. None of the present inventions disclose or describe a
device or a method as proposed in the present invention that uses vertical
linear and rotary motions of the component/workpiece in a vibrating slurry or
vibrating dry media.
OBJECTS OF THE INVENTION
It is therefore, an object of the present invention to propose an automatic
polishing device for surface finishing of complex-curved-profiled components
of turbo-machinery using vibrating slurry or vibrating dry media.
Another object of the invention is to propose an automatic polishing device
for surface finishing of complex-curved-profiled components of turbo
machinery which is enabled to perform automatic polishing by mounting the
component on the device’s spindle with rotary, linear and vibratory forces
imparting energy for polishing the component.

A further object of the invention is to propose an automatic polishing device
for surface finishing of complex-curved-profiled components of turbo
machinery, which provides a consistent finish on the component with reduced
time for polishing.
A further object of the invention is to propose a method of automatic
polishing of complex-curved-profiled components of turbo-machinery.
SUMMARY OF THE INVENTION
Accordingly, there is provided an automatic polishing device and a method for
surface finishing of complex-curved-profiled components of turbo machinery.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure-1 is a view of the device for automatic polishing of different sizes of
complex-curved turbo-machinery components with rotary swing arm for
loading and unloading of components.
Figure-2 is a view of the device for automatic polishing of different sizes of
complex-curved turbo-machinery components with movable tank for loading
and unloading of components.
Figure-3 is a view of the steps for automatic polishing of different sizes of
complex-curved turbo-machinery components in different directions.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides an automatic polishing device and a method
for the surface finishing of turbo-machinery components with varying
diameters having complex-curved-profiles. Automatic polishing is performed
by mounting the component on the device’s spindle with rotary, linear and

vibratory forces imparting energy for polishing the component. The device
and method proposed in the present invention are aimed to provide a
consistent surface finish on the component with reduced time for polishing
and replace the existing manual process.
In an embodiment of the present invention, the device comprising a
stationary vertical column 15; a stationary base plate 16; a vertically moving
horizontal arm 17; and a slurry tank 31 capable of vibrating; an electrically
driven a.c., d.c. or servo motor 11, capable of being driven at variable speed
and attached to the vertical column 15 and driving a gear box 12 which in
turn drives a ball screw or a lead screw 13 mounted with a ball screw nut or
lead screw nut 14 and which is attached to a horizontal arm 17; an
electrically driven a.c., d.c. or servo motor 21 attached to the horizontal arm
17 and rotating at variable speed, and driving a gear box 22, wherein the
rotation of the ball screw or lead screw 13, causes a linear up/down motion
of the ball screw or lead screw nut 14 at variable speed, the linear motion of
the ball screw or lead screw nut 14 is transferred to the horizontal fabricated
arm 17 attached to the ball screw or lead screw nut 14, wherein the
movement of the horizontal arm 17 causes the assembly of the motor 21, the
gear box 22, the shaft 23 and a component 51 to move linearly up or down
depending on the clockwise or counter-clockwise rotation of the motor 11,
wherein the gear box 22 drives the shaft 23 on which the component (51) to
be polished is attached allowing the component 51 to rotate clockwise or
counter-clockwise depending on the direction of turning of the motor 21, and
wherein the horizontal arm 17 is rotatable by manual or automated means to
load and unload the component 51, and wherein
a slurry tank 31 is mounted on springs 43 and having an variable speed
electric motor 42, which is mounted at the bottom of slurry tank 31, the
motor 42 having eccentric weights mounted on the shaft that causes the
vibration of the slurry tank 31 which in turn causes vibrations of the slurry 32.

In another embodiment of the present invention, a method of automatic
polishing of complex curved profiled components of turbomachinery moving
the component 51 linearly up and down by combination of ball screw 13 and
nut 14 in the slurry tank 31. While moving linearly up and down, the
component is also rotated clockwise and/or counter-clockwise by combination
of the motor 21 and gear box 22. Thus the combination of forces due to
vertical linear motion, rotary motion and vibratory motion of the slurry 32 are
imparted to the component 51 to achieve the polishing of the component 51.
The first step in the said method consists of vibrating the slurry and rotating
the component in first direction around longitudinal axis of the work-piece
including in first direction of translation along the longitudinal axis; vibrating
the slurry and rotating the component in second direction that is opposite to
the first direction around longitudinal axis of the work-piece including in the
second direction that is opposite to the first direction of translation along the
longitudinal axis; and repeating the said steps alternately to achieve the
polishing of the component.
In another embodiment of the present invention, the slurry in the slurry tank
is replaced by, but not limited to, the dry polishing media such as cylindrical
angle cut ceramic media or triangular angle cut ceramic media.
In another embodiment of the present invention, the slurry tank is mounted
on the wheels 61 which travels on the rails 62, allowing the slurry tank to
occupy two positions, wherein in the first position below the spindle 23, the
component is polished and wherein in the second position away from spindle
23, the component is loaded or unloaded.

WE CLAIM :
1. An automatic polishing device for surface finishing of complex-curved-
profiled components of turbo machinery, comprising a stationary
vertical column 15; a stationary base plate 16; a vertically moving
horizontal arm 17; and a slurry tank 31 capable of vibrating; an
electrically driven a.c., d.c. or servo motor 11, capable of being driven
at variable speed and attached to the vertical column 15 and driving a
gear box 12 which in turn drives a ball screw or a lead screw 13
mounted with a ball screw nut or lead screw nut 14 and which is
attached to a horizontal arm 17; an electrically driven a.c., d.c. or
servo motor 21 attached to the horizontal arm 17 and rotating at
variable speed, and driving a gear box 22, wherein the rotation of the
ball screw or lead screw 13, causes a linear up/down motion of the ball
screw or lead screw nut 14 at variable speed, the linear motion of the
ball screw or lead screw nut 14 is transferred to the horizontal
fabricated arm 17 attached to the ball screw or lead screw nut 14,
wherein the movement of the horizontal arm 17 causes the assembly
of the motor 21, the gear box 22, the shaft 23 and a component 51 to
move linearly up or down depending on the clockwise or counter-
clockwise rotation of the motor 11, wherein the gear box 22 drives the
shaft 23 on which the component (51) to be polished is attached
allowing the component 51 to rotate clockwise or counter-clockwise
depending on the direction of turning of the motor 21, and wherein
the horizontal arm 17 is rotatable by manual or automated means to
load and unload the component 51, and wherein
a slurry tank 31 is mounted on springs 43 and having an variable
speed electric motor 42, which is mounted at the bottom of slurry tank
31, the motor 42 having eccentric weights mounted on the shaft that
causes the vibration of the slurry tank 31 which in turn causes
vibrations of the slurry 32.

2. A method of automatic polishing of complex-curved-profiled
components of turbo-machinery, the said method consists of vibrating
the slurry and rotating the component in first direction around
longitudinal axis of the work-piece including in first direction of
translation along the longitudinal axis; vibrating the slurry and
rotating the component in second direction that is opposite to the first
direction around longitudinal axis of the work-piece including in the
second direction that is opposite to the first direction of translation
along the longitudinal axis; and repeating the said steps alternately to
achieve the polishing of the component.
3. The device as claimed in claim 1, wherein the slurry in the slurry tank
is replaced by the dry polishing media such as cylindrical angle cut
ceramic media or triangular angle cut ceramic media.
4. The device as claimed in claim 1, wherein the slurry tank is mounted
on the wheels 61 which travels on the rails 62, allowing the slurry tank
to occupy two positions, wherein in the first position below the spindle
23, the component is polished and wherein in the second position
away from spindle 23, the component is loaded or unloaded.