FIELD OF INVENTION
The present invention relates to angular winding machine for manufacture of
bristle pack to build brush seals used in steam turbines, gas turbines, compressors and pumps
and method of manufacturing. The invention specifically relates to a mechanism by which the
winding on a circular plate is done at a particular angle which is a requirement for building the
seals.
BACKGROUND:
Brush seals are used in various process equipment like steam turbines, gas
turbines, compressors and pumps etc to reduce the leakage and increase the internal process
efficiency.
Brush seals offer superior leakage control compared to labyrinth seals owing
to their compliant nature and ability to maintain very tight clearance to the rotating shaft. Brush
seals can have important effects on the overall turbine system that must be taken into account
to assure reliable operation.
Brush seals are concentric and are made in two halves (split seals) to insert
into the casings, which are all mostly made in two halves. The brush seals are built with bristle
packs, which are an assembly of thin high temp alloy wires of dia ranging from 0.1 mm to 0.15
mm. The assembly is such that the wires are arranged not radially but it an angle ranging from
35° to 45° called as cant or lay angle.
Since the thin wires need to be arranged in an angular manner and that too
very compactly in order to avoid leakage through the wires, the method of such laying is unique
and also the critical part.

Non radial winding, like the brush seal winding is usually done through a method
of toroidal winding which will be modified to meet the specified winding requirement. In toroidal
winding method, the spools of wire move around the object, on which the wire has to be wound
usually called as form plate. The use of toroidal winding process has been dispensed with in this
invention, where the form plate is revolved around an axis perpendicular to the angle of lay or
cant angle and in the process the wire gets wound from the spool (s).
The special purpose angular winding that is required as stated above requires a
machine or system for winding. Even the general purpose winding machines or the special
purpose winding machines like toroidal winding machines cannot be used directly for this
requirement and have to be modified and adapted further before using them for angular winding
process.
Some of the prior art patents with reference to the use of toroidal winding method
for winding the brush seal are as given below:
a) The patent no US2007/0214628 Al published on Sep 20, 2007.
b) The patent no US 4204629 published in 1980.
c) The patent no US 4732339 published in 1988.
US Patent No. US4204629 Al discloses a method of manufacturing brush seal by
an arrangement of winding filaments on the bristle material, where the winding and operation
are carried out by a toroidal or spiral winding machine, in which an annular filament carrier is
mounted for rotation in rollers and the article to be wound passes through the carrier. The
speed of rotation of the filament carrier and the article to be wound are adjusted by a gear
connection. Similarly US Patent No. US2007/0214628 and US4732339 describe brush seal
manufacturing device, which is based on the conventional toroidal winding machine. The
proposed invention is a significant modification to the referred prior art in so far the method of

winding is concerned, wherein the toroidal winding method is dispensed with and the angular
winding method with newly developed angular winding machine is used. This method is simple,
cost effective and achieves better quality of efficient winding.
The disadvantages associated with toroidal winding is the cost. The nature of a
toroidal wire necessitates slower, more complex winding techniques, particularly for high-voltage
or multi output machines where many wire changes or many turns are required.
The proposed invention is a significant modification to the referred prior art in so
far the method of winding is concerned wherein the toroidal winding method is dispensed with
the angular winding method using the newly developed angular winding machine of the proposed
invention. This method is simple, cost effective and achieves better quality of winding.
OBJECTS OF THE INVENTION:
Therefore it is an object of the invention to propose an angular winding machine
for manufacture of bristle pack to build brush seals and method of manufacturing, which is
capable of providing the mechanism by which the winding on a circular plate is done at a
particular angle to suit the requirement for building the seals.
Another object of the invention is to propose an angular winding machine for
manufacture of bristle pack to build brush seals and method of manufacturing which facilitates a
method to manufacture bristle pack which is simple and cost effective.
A further object of the invention is to propose an angular winding machine for
manufacture of bristle pack to build brush seals and method of manufacturing which is capable
of producing better quality product and higher productivity.
A still further object of the invention is to propose an angular winding machine for
manufacture of bristle pack to build brush seals and method of manufacturing which is able to
meet the requirement of angular winding without using the toroidal winding machine.

SUMMARY OF THE INVENTION:
According to the invention an angular winding machine is developed. It
comprises:
Angular winding plate on which the winding is done and it is held or guided
circumferentially with the help of a guide plate. Both the plates are held on an axis, which is
perpendicular to the angle of lay (35° to 45°). When the winding plate is rotated around the
axis, the wires take the radial position for winding and after this the next position of the plate is
brought through circumferential movement and the winding proceeds in this manner.
The proposed angular winding machine works on the concept, where the form
plate, i.e. the object on which the wire has to be wound, is revolved around an axis which is
perpendicular to lay angle or cant angle, and in the process the wire gets wound by the spool.
BRIEF DESCRIPTION OF THE ACCOMPAYING DRAWINGS:
The invention can now be described in detail with the help of the figures of the
accompanying drawings in which
Figure 1 shows a 3 D view of the Angular winding Machine (W) with the following part
description:
MOUNTING FRAME (1)
BEARING HOUSING (2)
BRUSH SEAL GUIDE (3)
BRUSH SEAL WINDING PLATE (4)
BRUSH SEAL HOLDING FIXTURE OR WINDING PLATE GUIDE-DRIVE END (5)
BOBBIN OR WIRE SPOOL (7,8,9,10,11)
BOBBIN TENSIONER (12,13,14,15,16)
COUNT METER (6)
WIRE TENSIONER (24)
Figure 2 shows a Front view of the angular winding machine according to the invention.

Figure 3 shows a Top view of the angular winding machine according to the invention.
Figure 4 shows a back view of the angular winding machine according to the invention.
Figure 5 shows a winding plate according to the invention.
Figure 6 shows winding plate guide fixture-drive end.
Figure 7 shows Winding plate guide fixture- non drive end.
Figure 8 shows driven Shaft
Figure 9 shows Bearing Housing Assembly.
Figure 10 shows Counter Meter-Manual drive
Figure 11 shows Base/ Support Frame
Figure 12 shows Bobbin shaft
Figure 13 shows Conical Nut
Figure 14 shows Wire spool
Figure 15 shows wire Guide and tensioner
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION:
The invention is now described in an exemplary embodiment as depicted in the
accompanying drawing. There can however be other embodiments of the same invention, all of
which are deemed covered by this description.

The total angular winding assembly is mounted on a base/support frame as shown
in fig. 11.
The angular winding machine (W) is designed to wind the wires on a winding plate
(4), integral with the machine at an angle, which is always at 35° to 45° w.r.t. the radial
direction. The winding plate (4) is having number of slots (17) which are meant to guide the
wire (18) in that angle and has plurality of projected fins (19) disposed on the outer diameter of
the winding plate (4). The separation of projected fins (19) on the outer diameter of this plate
(4) are meant to held the wires in position. The depth of the fins (19) or the width of the
grooves depends upon the bristle pack density required for the seal.
To achieve the angular winding, the slots (17) in the winding plate (4) have to be
aligned at an axis perpendicular to the axis of rotation of the plate. To achieve this position, a
fixture called as winding plate guide - drive end (5) as shown in the figure 6 is designed. The
top view of this fixture shows the extended threaded pin to fix to the drive motor, a manual
drive (30) is used in this machine.
The other end of the winding plate is coupled to the non drive end or support end
by fixing it on the fixture called as winding plate guide - non drive end as shown in fig 7. This
fixture also achieves outer radius concentricity through the circumferential projection which acts
as a circumferential locater.
The winding plate guide - non drive end is attached to the non drive end axis
through a specially designed driven shaft (25) as shown in fig 8. This shaft has an L-clamp
section in the end to accommodate the winding guide plate- non driven end.
The winding on this winding plate (4) can be done using an angular winding
machine (W) as invented, wherein the wire spool will revolve around this plate. This machine
brings in the innovation of revolving this plate (4) at an axis, which is always perpendicular to
the angle of wire lay. The arrangement of the winding plate (4) revolving in an axis and
obtaining the movement of the plate in such a manner makes the winding continuous and also
at the desired angle.

The winding plate (4) is guided to move one grove (20) at a time after winding
with the help of a plate (3) called as brush seal guide or winding plate guide. This plate's (3)
uniqueness is that it has a fork (21) which is milled or machined from the OD of the guide plate
(3) at the angle of the wire lay say 35°. This angle of the fork (21) in fact exactly locates the
groove (20), in which the winding will be done at an axis, which is perpendicular to it. At any
point of winding, one groove (20) is in position and to bring the next groove into the winding
position the winding plate (4) is moved circumferentially by one pitch of say 2° so that the next
groove comes in place for the winding.
This calibrated movement according to the invention is achieved with the help of
pin locating hole (23) at the required pitch.
The projection on the OD of the guide plate (3) also helps maintain OD reference
position accurately along with the location achieved with the help of guide holes (23). The guide
plate (3) and the holes (23) are seen clearly in Top view -Fig 3. The guide plate (3) with the
fork (21) is designed in such a way that it matches the rotating shaft (25) of the bearing
housing (2) to align the winding plate groove perpendicular axis. The L shaped bracket (22) of
the shaft (25) locates the fork (21) of the guide plate.
The brush seal holding fixture can be split or can be a single plate with a radial
groove to locate and support the winding plate on the other end of the axis.
As shown in fig. 1 and fig. 9 the angular winding machine (W) has a bearing
housing (2) mounted on frame (28) which holds a shaft (25) in position. The fork (21) of the
guide plate (3) is held in position on the projected L shape bracket (22) of the shaft (25) from
one side and by the brush seal holding fixture (5) called as winding plate guide-drive end fixture
on the other side of the axis.
As shown in Fig. 1, the wire is supplied through a 5 wire spool arrangement which
is arranged on the mounting frame (1). The wire spool assembly consists of a bobbin shaft (29)
as shown in Fig 12 and fig 1 and the spool is locked with a conical holding nut as shown in fig
13 and fig. 1 and wire spool as shown Fig. 14. This nut called the bobbin tensioner
(12,13,14,15,16) controls the bobbin speed to maintain the required wire release tension.

The angular winding machine (W) has five bobbin spools (7,8,9,10,11) as shown
in fig. 14 and fig.l fixed on the mounting frame (1) of the machine (W). These bobbins are
variable based on the requirement. The wires (18) are supplied through five bobbin spools
(7,8,9,10,11). The bobbins (7,8,9,10,11) are allowed to unwind the wire (18) under tension
through the use of bobbin tensioners (12,13,14,15,16) and wire tensioner (24) fixed on the
frame 26 attached to the mounting frame (1) of the winding machine (W). The wire tension
during winding is maintained through the use of the wire tensioner (24). The wire tensioner (24)
maintains adequate wire tension during winding process as the winding produces differential
tension twice during one revolution. The bobbin tensioners (12,13,14,15,16) are disposed on
the bobbin spools (7,8,9,10,11) which are fixed on the vertical frame (27) of the mounting
frame (1) of the winding machine (W). The bobbin tensioners (12,13,14,15,16) maintains
bobbin wire release tension as any looseness will hamper the quality of winding.
All the above mentioned components are mounted on the base frame called as
mounting frame (1).
After positioning the slot (17) of the winding plate (4) through a pin between
winding plate (4) and the guide plate (3), the wires (18) are initially wound outside the groove
to create the tension and then it is wound in the grooves (20). After finishing one groove, the
next groove is brought into position by removing the pin from one hole and again fixing in the
next hole. In this innovative manner, the groove (20) is moved exactly by one pitch say 2°. The
guide plate (3) is having holes on a chosen pitch circle diameter at a required pitch so that the
groove for winding comes into exact position.
The winding system is driven through manual drive as shown in Fig 10, which also
has a counter to keep track of number of winding turns.
The number of wire wounds that have been done are counted with the help of a
counter mechanism (6) fixed on one end of the winding machine (W). The wire counter system
is used to maintain and achieve the required bristle thickness.

In this manner, the winding plate is progressively and continuously wound for a
sector say 60°.
This method of arranging the winding plate (4) in an axis that is perpendicular to the
angle of lay and moving it progressively by one pitch is done with the help of guide plate (3)
with guide pin and thus the angular winding for one sector is completed.
One total concentric seal of 360° is completed by completing six such sectors.

WE CLAIM
1. An angular winding machine for manufacture of bristle pack to build brush seals
comprising;
a mounting frame (1);
a plurality of bobbins (7,8,9,10,11) or wire spool attached to a vertical frame (27)
of the mounting frame (1) for carrying and unwinding the wires (18) under tension
through bobbin tensioner (12,13,14,15,16) and wire tensioner (24); a plurality of
conical holding nut or bobbin tensioner (12,13,14,15,16) disposed on the bobbins
or wire spool (7,8,9,10,11) for controlling the bobbin speed to maintain the
required wire release tension;
a brush seal holding fixture (5) fixed to the countmeter for connecting the winding
plate to the drive end.
a bearing housing (2) mounted on frame (28) of the machine frame (1) holding a
shaft (25) and a L shaped bracket (22) at the end of shaft (25);
characterized in that,
a winding plate (4) is disposed on the machine for winding the wires at an angle
which is always at 35° to 45° with respect to the radial direction when the slots in
the winding plate (4) are disposed for guiding the wire (18) in that angle and the
projected fins (19) are disposed on the outer diameter of the plate (4) for holding
the wires in position wherein the brush seal guide (3) is disposed on the machine
for guiding the winding plate (4) to move one groove (20) at a time.
2. The winding machine as claimed in claim 1, wherein the winding plate (4) and the
guide plate (3) are disposed on a axis which is perpendicular to the angle of lay
(35° to 45°).
3. The winding machine as claimed in claim 1, wherein the guide plate (3) holds a
fork (21) machined from the outer diameter of the guide plate (3) at the angle of
the wire lay 35° for exactly locating the groove (20) for winding at a axis
perpendicular to it.

4. A method of angular winding for manufacturing bristle pack by the winding
machine claimed in claim 1 comprising;
aligning the slots (19) in the winding plate (4) at an axis perpendicular to the axis
of rotation of the plate to guide the wires on winding plate (4) at an angle of 35°
to 45° with respect to the radial direction;
fixing the extended threaded pin to the drive motor;
arranging a manual drive;
achieving outer radius concentricity through circumferential projection acting as a
circumferential locater;
driving the winding system through manual drive;
keeping track of number of winding turns through counter mechanism (6);
Supplying the wires through a 5 wire spool (7,8,9,10,11) arrangement;
Wherein after positioning the slot (17) of the winding plate (4) through a pin
between winding plate (4) and the guide plate, the wires are initially wound
outside the groove (20) to create the tension and then wound in the grooves when
after finishing one groove, the next groove is brought into position by removing
the pin from one hole and fixing in the next hole to move the groove (20) exactly
by one pitch of 2° so that the winding plate is progressively and continuously
wound for a sector of 60° and eventually one total concentric seal of 360° is
completed.