FIELD OF INVENTION
[001] The invention is involved with the operation of taper grinding of
surfaces of stubs or turbine blades of non-magnetic materials in a fixture
having feature for angle adjustment according to required taper of the
work-piece. In particular, the invention relates to method of taper grinding
of non-magnetic workpiece at both pressure and suction sides.
BACKGROUND OF THE INVENTION
[002] Background description includes information that may be useful in
understanding the present invention. It is not an admission that any of
the information provided herein is prior art or relevant to the presently
claimed invention, or that any publication specifically or implicitly
referenced is prior art.
[003] The present invention is developed while it has been required to taper
grind the pressure and suction sides of steam turbine blade or stub roots
of non-magnetic materials in CNC creep feed grinding machine. In the CNC
creep feed grinding machine, any work pieces of magnetic materials are
easily clamped with magnetic table of the machine but in case of non-
magnetic materials a separate fixture arrangement has been required for
the operation. Hence there exists a need to develop means and method for
grinding blade stubs in CNC creep feed grinding machine without any
issues as in the case with prior art.

OBJECTIVE OF THE INVENTION
[004] The principal objective of this invention is to provide an improved
method of grinding nonmagnetic blade stubs that can eliminate the need
of a separate fixture arrangement required for the said blade stub
machining operation.
[005] Another objective of the present invention is to develop a method and
fixture for taper grinding of stubs or turbine blades of non-magnetic
materials having taper angle at both sides of roots.
SUMMARY OF THE INVENTION
[006] The present invention provides a device and method of taper grinding
of non-magnetic workpiece like turbine blade or blade stub at both the
pressure and suction sides. The present invention performs the taper
grinding with spindle wheel machine and does not involve any separate
fixing arrangement for fixing the non-magnetic workpiece on the system.
The plurality of clamps and bolts are configured to fix the workpiece on
the machine table and is tightened by sliding slide carriage. The preferred
embodiment is configured with angular adjustment of the position of the
workpiece placed on taper plate. The grinding wheel machine performs the
taper grinding the pressure side at root part keeping top part flat. By
flipping upside down the suction side of the same workpiece is grinded
with similar method at root part.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
[007] Various objects, features, aspects, and advantages of the inventive
subject matter will become more apparent from the following detailed
description of preferred embodiments, along with the accompanying
drawing figures in which like numerals represent like components.
[008] It is to be understood that the aspects and embodiments of the
disclosure described below may be used in any combination with each
other. Several of the aspects and embodiments may be combined to form
a further embodiment of the disclosure.
[009] The foregoing summary is illustrative only and is not intended to be
in any way limiting. In addition to the illustrative aspects, embodiments,
and features described above, further aspects, embodiments, and features
will become apparent by reference to the drawings and the following
detailed description.
[010] The figures depict embodiments of the disclosure for purposes of
illustration only. One skilled in the art will readily recognize from the
following description that alternative embodiments of the structures and
methods illustrated herein may be employed without departing from the
principles of the disclosure described herein.

[011] Figure 1: Isometric embodiment of the present invention showing
possible linear movements of clamps indicated with thick double-sided
arrow.
[012] Figure 2: Internal arrangement under surface “C” of taper
adjustment system.
[013] Figure 3: Adjustment of wedge platform angle
[014] Figure 4: Top view of disassembled system
[015] Figure 5: Isometric view of Base body of taper adjustment system
[016] Figure 6: Placement of workpiece on the system along with grinding
wheel action
[017] Figure 7: Front view of placement of workpiece on the system
[018] Figure 8: Side view of placement of workpiece on the system
[019] Figure 9: Single workpiece with the profile of root and “rhomboid”
angle β
[020] Figure 10: Taper grinding of surface “A” from “A1” and Surface “B”
from “B1”
[021] Figure 11: Top view of the system without placing workpiece
[022] Fig 12: Top view of Base body of taper adjustment system
[023] Fig 13: Configuration of slide carriage (12)

[024] Fig 14: Configuration of Type 1 clamps having angle β (upward) with
vertical axis
[025] Fig 15: Configuration of Type 2 clamps having angle β (downward)
with vertical axis
[026] Fig 16: Configuration of pivot rod (13)
[027] Fig 17: Configuration of taper plate (15)
[028] Fig 18: Configuration of Lead screw (10)
[029] Fig 19: Configuration of Angle adjustment bolt (1)
[030] Fig 20: Configuration of Taper system base slide (14)
[031] Fig 21: Configuration of Clamping bolts (6, 7, 8, 9)
DETAIL DESCRIPTION OF THE PRESENT INVENTION WITH
REFERENCE TO THE ACCOMPANYING DRAWINGS OF PREFERRED
EMBODIMENTS
[032] While the embodiments of the disclosure are subject to various
modifications and alternative forms, specific embodiment thereof have
been shown by way of example in the figures and will be described below.
It should be understood, however, that it is not intended to limit the
disclosure to the particular forms disclosed, but on the contrary, the
disclosure is to cover all modifications, equivalents, and alternative falling
within the scope of the disclosure.

[033] Figure 1 is an isometric embodiment (11) of the present invention
embedded with first pair of angular slide able clamps type-1 (3, 4), second
pair of angular slide able clamps type-2 (2, 5) and clamping bolts (6, 7, 8,
9). The configuration of Clamping bolts (6, 7, 8, 9) is shown in Figure 21.
[034] The linear possible movements of first pair of angular slide able
clamps type-1 (3, 4) and a second pair of angular slide able clamps type-
2 (2, 5) are shown with solid arrows. A slide carriage (12) is configured in
the preferred embodiment (11) to move forwards or backwards by rotating
lead screw (10) to tighten the work piece along the length as shown with
solid arrow on it. The upper surface of the (12) is referred as Surface “D”.
An angle adjustment bolt (1) is rotated clockwise or anti clockwise which
is realized by the lift of taper plate (15). The top surface of taper plate (15)
is the resting surface of work piece and is referred by Surface “C”.
[035] Figure 2 shows internal arrangement, particularly under surface “C”
of taper adjustment system (11) configured with angle adjustment bolt (1),
Pivot rod (13) and Taper system base slide (14). Figure 3 shows the close
views of taper adjustment system with taper plate (15) indicating wedge
platform adjustment.
[036] Figure 4 and Figure 12 show a disassembled view of the entire
system where angular slide able clamps type-1 (3, 4) and type-2 (2, 5) and
clamping bolts (6, 7, 8, 9) are removed. Isometric view of Base body of

taper adjustment system is shown in Figure 5. The entire setup is used to
clamp nonmagnetic work pieces in magnetic tables or surface tables of the
grinding machine for taper grinding. Figure 11 shows the top view of the
system without placing workpiece.
[037] Figure 9, 10 show views of a work piece, namely a steam turbine
blade or a stub, i.e. an equivalent blade without profile. In any case, the
root of the work piece has two tapered surfaces, denoted as “A” and “B”
(Figure 9). In Figure 10, surface A1 (PART 1) is taper grinded to surface
“A” (PART 3) in the pressure side of the work piece. Similarly, surface B1
(PART 2) is taper grinded to surface “B” (PART 4) in the suction side of the
work piece. While A1 and B1 are tapered, remaining surface A2 or B2
remain flat.
[038] The work piece surface A1 is butted on surfaces “C” and “D” of the
clamping fixture as shown in Figure 6. The front and side view of the
placement of workpiece on the system are shown in Figure 7 and Figure
8 respectively. The work piece is clamped in the said fixture system with
the aid of angular slide able clamps type-1 (3, 4), type-2 (2, 5) and
clamping bolts (6, 7, 8, 9) of Figure 1. The said angular slide able clamps
are manufactured according to angle “β” in work piece as illustrated in
Figures 9, 14 and 15. The angle “β” is called “rhomboid” angle of work
piece as shown in Figure 9 and is different for different types of jobs.
Accordingly, angular slide-able clamps of type 1 and type 2 are

manufactured with same angle “P" as shown Figure 14 and Figure 15 to
clamp the work piece.
[039] Linear adjustment is required for tightening the workpiece as shown
in Figure 1. The slide carriage (12) is moved forwards or backwards by
rotating lead screw (10) (referring Figure 1, 6, 7, 8) to tighten the work
piece along the length as shown in Figures 6. The configuration of slide
carriage (12) is shown in Figure 13. The configuration of the said lead
screw (10) is shown in Figure 18. Referring to Figure 2 and Figure 3, the
angle adjustment bolt (1) is rotated clockwise or anti clockwise to slide
taper system base slide (14) forward or back ward respectively so that
wedge platform angle “6” as shown in Figure 3 increases or decreases
respectively. This is realized by taper plate (15) as shown in Figure 3,
which is pivoted by pivot rod (13) as shown in Figure 2. The configuration
of pivot rod (13) is shown in Figure 16. As the taper system base slide (14)
moves front and back wards below the taper plate (15) having a tapered
surface as shown in Figure 20, the angle “6” as shown in Figure 3
increases or decreases respectively. The angle “6" is same as angle between
job surface (A1 and A) or (B1 and B) (referring Figure 3 and Figure 10). In
first operation, the angle “6” as shown in Figure 3 is adjusted to zero. The
configuration of the said angle adjustment bolt (1) is shown in Figure 19.
The configuration of the said taper system base slide (14) is shown in
Figure 20.

[040] Fixing the workpiece, the creep feed grinding wheel (Figure 6) of the
CNC grinding machine is run to grind the flat surface “A1” to form surface
“A” (referring Figure 9, Figure 10) thereafter. The grinding is performed
at root part “A1” keeping top part “A2” flat (referring Figure 10). Entire
production quantity is completed using the set up.
[041] Now to generate surface “B” from “B1” in suction side, the surface
“A” is rested on surface “C” and surface “A2” is rested on surface “D” by
flipping it upside down and making the suction side or surface “B1”
exposed for grinding.
[042] Next, the surface “B1” is taper grinded to surface “B” similarly by
tightening angular slide able clamps type-1 (3, 4) and clamps type-2 (2, 5)
and clamping bolts (6, 7, 8, 9) and the slide carriage (12) is moved
forwards or backwards by rotating lead screw (10) as shown in Figures 1,
7, 8 to tighten the work piece along the length as mentioned earlier. Next
the grinding wheel is run on the surface “B1” to generate surface “B”
(referring Figure 6) at root part keeping top part “B2” flat.
[043] As already surface “A” has a taper which has been generated by
previous taper grinding operation, the surface “C” as shown in Figure 1 is
given a taper angle “Ɵ” by operating the said adjustment bolt (1) so that
the top surface “B1” (Figure 10) remains parallel to the machine table or
base. This is minutely checked by using a dial with magnetic stand (Figure
6), clamped in the grinding wheel spindle and sliding the same on the flat

surface “B1”. The taper angle given to taper adjustment system is as same
as generated in surface A so that the surface B1 remains parallel to
machine table during grinding of surface B1. Next the grinding wheel is
run on the surface “B1” to generate surface “B”.
[044] In the present invention, the two tapered surfaces “A” on pressure
side and “B” on suction side of the workpiece are generated by taper
grinding with the taper adjustment system. The side (pressure or suction)
of operation for taper grinding can be performed vice versa.
[045] Each of the appended claims defines a separate invention, which for
infringement purposes is recognized as including equivalents to the
various elements or limitations specified in the claims. Depending on the
context, all references to the "invention" may in some cases refer to certain
specific embodiments only. In other cases, it will be recognized that
references to the "invention" will refer to subject matter recited in one or
more, but not necessarily all, of the claims.
[046] Groupings of alternative elements or embodiments of the invention
disclosed herein are not to be construed as limitations. Each group
member can be referred to and claimed individually or in any combination
with other members of the group or other elements found herein. One or
more members of a group can be included in, or deleted from, a group for
reasons of convenience and/or patentability. When any such inclusion or

deletion occurs, the specification is herein deemed to contain the group as
modified thus fulfilling the written description of all groups used in the
appended claims.
[047] It will be understood by those within the art that, in general, terms
used herein, and especially in the appended claims (e.g., bodies of the
appended claims) are generally intended as “open” terms (e.g., the term
“including” should be interpreted as “including but not limited to,” the
term “having” should be interpreted as “having at least,” the term
“includes” should be interpreted as “includes but is not limited to,” etc.).
It will be further understood by those within the art that if a specific
number of an introduced claim recitation is intended, such an intent will
be explicitly recited in the claim, and in the absence of such recitation no
such intent is present. For example, as an aid to understanding, the
following appended claims may contain usage of the introductory phrases
“at least one” and “one or more” to introduce claim recitations. However,
the use of such phrases should not be construed to imply that the
introduction of a claim recitation by the indefinite articles “a” or “an” limits
any particulars claim containing such introduced claim recitation to
inventions containing only one such recitation, even when the same claim
includes the introductory phrases “one or more” or “at least one” and
indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically
be interpreted to mean “at least one” or “one or more”); the same holds
true for the use of definite articles used to introduce claim recitations. In

addition, even if a specific number of an introduced claim recitation is
explicitly recited, those skilled in the art will recognize that such recitation
should typically be interpreted to mean at least the recited number (e.g.,
the bare recitation of “two recitations,” without other modifiers, typically
means at least two recitations, or two or more recitations). Furthermore,
in those instances where a convention analogous to “at least one of A, B
and C, etc.” is used, in general such a construction is intended in the sense
one having skill in the art would understand the convention (e.g., “a
system having at least one of A, B and C” would include but not be limited
to systems that have A alone, B alone, C alone, A and B together, A and C
together, B and C together, and/or A, B, and C together, etc.). In those
instances, where a convention analogous to “at least one of A, B, or C, etc.”
is used, in general such a construction is intended in the sense one having
skill in the art would understand the convention (e.g., “a system having at
least one of A, B, or C” would include but not be limited to systems that
have A alone, B alone, C alone, A and B together, A and C together, B and
C together, and/or A, B, and C together, etc.). It will be further understood
by those within the art that virtually any disjunctive word and/or phrase
presenting two or more alternative terms, whether in the description,
claims, or drawings, should be understood to contemplate the possibilities
of including one of the terms, either of the terms, or both terms. For
example, the phrase “A or B” will be understood to include the possibilities
of “A” or “B” or “A and B”.

[048] The above description does not provide specific details of
manufacture or design of the various components. Those of skill in the art
are familiar with such details, and unless departures from those
techniques are set out, techniques, known, related art or later developed
designs and materials should be employed. Those in the art are capable of
choosing suitable manufacturing and design details.
[049] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of the
present disclosure. It will be appreciated that several of the above-
disclosed and other features and functions, or alternatives thereof, may be
combined into other systems or applications.
[050] Although embodiments for the present subject matter have been
described in language specific to structural features, it is to be understood
that the present subject matter is not necessarily limited to the specific
features described. Rather, the specific features and methods are disclosed
as embodiments for the present subject matter. The claims, as originally
presented and as they may be amended, encompass variations,
alternatives, modifications, improvements, equivalents, and substantial
equivalents of the embodiments and teachings disclosed herein, including
those that are presently unforeseen or unappreciated, and that, for
example, may arise from applicants/patentees and others.

ADVANTAGE OF THE INVENTION
[051] The advantage of this invention is that it provides an improved
method of grinding nonmagnetic blade stubs without the need of a
separate fixture arrangement for the said blade stub machining operation.
[052] Another advantage of the present invention is that it develops a
method and fixture for taper grinding of stubs or turbine blades of non-
magnetic materials having taper angle at both sides of roots.

WE CLAIM:
1. A device of taper grinding of nonmagnetic blade stub or turbine
blade workpiece at pressure and suction sides, comprising of:
- A Base body with taper adjustment system (11), embedded with
- First pair of angular slide-able clamps type 1 (3, 4), second pair of
angular slide-able clamps type 2 (2, 5), a plurality of Clamping bolts
(6, 7, 8, 9) for tightening the workpiece on the said system (11),
wherein type 1 (3, 4) and type 2 (2, 5) are configured with same
“rhomboid” angle “β”to clamp the said work piece;
- A slide carriage (12) with upper surface “D”, moving forwards or
backwards by rotating lead screw (10) for tightening the work piece
along its length;
- A taper plate (15) with upper surface “C”, pivoted by pivot rod (13)
atop base slide (14) for placing the workpiece thereon;
- An Angle adjustment bolt (1), for sliding taper system base slide (14)
forward or back ward with workpiece thereupon, wherein movement
of (14) makes angular lift “θ” of the taper plate (15) thus, surface “C”
upon the surface table;
- A grinding wheel spindle machine embedded with a dial attached
with magnetic stand clamped therein for grinding the sides of
workpiece.
2. The device as claimed in claim 1, wherein the said angular slide able
clamps type 1 (3, 4) and type 2 (2, 5) are adjusted with linear

movements for clamping of the said work piece upon the system and
are configured with same “rhomboid” angle β for clamping the
workpiece.
3. A method of taper grinding of nonmagnetic blade stubs or turbine
blade workpiece on both sides, comprises the steps of:
- Placing pressure side surface “A1” of work piece on upper
surface “C” of taper plate (15) and upper surface “D” of slide
carriage (12) of the clamping fixture system (11) for
performing grinding;
- Clamping the work piece in the said fixture system with the
aid of angular slide able clamps type-1 (3, 4), type-2 (2, 5)
and clamping bolts (6, 7, 8, 9) for tightening the said work
piece on the surface table of the system (11);
- Adjusting the said angular slide able clamps type-1 (3, 4),
type-2 (2, 5) according to “rhomboid” angle “β” of work piece
for proper clamping of the work piece,
- Tightening the work piece along its length by sliding slide
carriage (12) with upper surface “D” forwards or backwards
by rotating lead screw (10),
- Rotating the angle adjustment bolt (1) clockwise or anti
clockwise to slide taper system base slide (14) forward or back
ward respectively below the taper plate (15) pivoted by pivot
rod (13) for increasing or decreasing the wedge platform angle

“Ɵ”, wherein adjustment of “Ɵ” provides necessary angular
lifting adjustment of said taper plate (15);
Adjusting the said angle “Ɵ” to be zero;
Running creep feed grinding wheel of the grinding machine to
grind the flat surface “A1” (PART 1) to form surface “A” (PART
3) at root part keeping top part “A2” flat;
Resting the surface “A” on surface “C” and surface “A2” on
surface “D” flipping over thereon;
Exposing the suction side surface “B1” of work piece on
surfaces “C” and “D” for grinding;
Taper grinding the surface “B1” (PART 2) to surface “B” (PART
4) by tightening angular slide able clamps type-1 (3, 4) and
clamps type-2 (2, 5) and clamping bolts (6, 7, 8, 9) and
moving the slide carriage (12) forwards or backwards by
rotating lead screw (10) for tightening “B1” along its length as
prior mentioned;
Running the grinding wheel on the surface “B1” to generate
surface “B” at root part keeping top part “B2” flat;
Maintaining the top surface “B1” parallel to the machine table
by giving the surface “C” a taper angle “Ɵ” as same as
generated in surface “A” by operating the said adjustment bolt
(1), wherein a dial attached with magnetic stand clamped in
the grinding wheel spindle sliding on “B1” provides necessary
measurement;

- Generating two tapered surfaces “A” on pressure side and “B”
on suction side of the workpiece with the taper adjustment
system (11) with the order of operation on any side first.
4. The method as claimed in claim 4, wherein it grinds nonmagnetic blade
stubs or turbine blade workpiece avoiding the requirement of a separate
fixture arrangement for fixing pressure and suction sides.
5. The method as claimed in claim 4, wherein the angular adjustment of
wedge platform angle “6” provides angular adjustment of taper plate
(15) with workpiece placed thereupon for proper position of workpiece
during grinding operation of required surface.