The present invention relates to An Improved mounting arrangement for
alternators in space constrained bogies of railway vehicles and like
transits and methods thereof.
BACKGROUND OF THE INVENTION
It has been seen that there are not many proposals in the past regarding
mounting arrangements for alternators in space constrained railway bogies.
Description of Prior art
In the prior arts, the brushless alternators had been mounted underneath
bogie frames as transom mount along with tensioning rod type arrangement
in order to install V-belts and carry out procedures of belt tensioning. These
arrangements require considerable space to mount the alternator and are
applicable for certain types of bogies, specially designed to accommodate
such type of alternator arrangements. As the train speeds are increasing day
by day the bogies are getting lightweight and compact along with integration
of complex stability maintaining mechanisms, leading virtually no space to
install alternators as it was done with previous methods.
There have been proposals for mounting costly permanent magnet
alternators employing rare earth magnets due to its smaller size as
compared to brushless alternators, however the pricing and availability of
rare earth magnets is of great concern. If the demand of such specialty
alternator increases then the pricing will also increase due to the scarcity of
rare earth magnets. These alternators also require complex electronics and
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power converters to stabilize output voltage which further increases the
pricing to great extent.
US2743680, Mounting for generator on railway car truck, teaches a method
to mount the alternator beneath the bogie frame. This method is applicable
for certain makes and types of bogies which are big in size and are designed
for low speed and have larger frames. However such a method is more or
less useless for compact high speed bogies.
The problem to be addressed is by providing a conventional low cost
brushless alternators on the upper side of the bogie crossbeam and
positioned in such a manner, that their respective pulleys, faces each other
on same axis and towards the center of the axle; thereby providing more
alternator length along its rotational axis and with reduced diameter, enabling
it to be accommodated in less vertical space. A detachable hollow drive
pulley mounted on the prime movers axle such that it could be loosened to
accommodate mounting and changing of plurality double sided V-belts. A
belt tensioning arrangement for the alternator is disposed by mounting
plurality rollers on the belts, along with a sliding carriage holding both the
alternators firmly in place. The sliding carriage is disposed with screws to
position the said carriage and hence the alternators, with respect to its drive
pulley; thereby further facilitating the belt tensioning and alignment in space
constrained bogies.
The invention relates more particularly to Fiat type or similar bogies
developed and designed by manufacturer ‘Linke Hofmann Busch’ (LHB) and
employing a conventional brushless alternator but not by way of limitation, to
such apparatus and method utilizing other type of alternators and on different
manufacturer’s make and type of bogies.
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OBJECTS OF THE INVENTION
It is therefore the object of the invention to provide dual alternators with their
respective driven pulleys facing each other along the axis of rotation and
firmly mounted on the bogies crossbeam.
It is another object of the invention to increase the length of the alternators
along the axis of rotation and decrease the diameter to enable its
accommodation in vertically space constrained bogies.
It is another object of the invention to provide a sliding carriage with firmly
mounted alternators along with plurality screw and slot arrangement to adjust
the carriage and alternators in x/y-axis thereby further facilitating the belt
alignment and its tensioning in space constrained bogies.
It is another object of the invention to mount the sliding carriage along with
the alternators on the top of the bogie crossbeam just below the car-body
floor.
It is another object of the invention to mount the alternators on the top of the
bogie’s crossbeam, below the car-body with appropriately placed mounting
brackets and guide slots with matching holes to replace or unmounts the
alternators when defective or during the events of V-belt changing .
It is another object of the invention to provide suitable gap in between the
alternators respective pulleys facing each other to facilitate loading of the
plurality double sided V-belts and the said pulleys are thereafter coupled
together with a suitable coupler and flange arrangement to further stabilize
the alternator arrangement for high power and vibratory environment.
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It is another object of the invention to provide a double sided V-belt to drive
the pulleys along with a suitable belt tensioning arrangement with plurality
rollers pressing the double sided V-belts and further facilitating belt
tensioning in day to day activities.
A further object of the invention is to provide a hub mounted detachable drive
pulley on axle, in a hub mounting arrangement with plurality nuts on the
pulley and an axle mounted, split mount type fixed flange to detach and fix
the pulley in proper place.
A further object of the invention is to enable detachment of the hub mounted
pulley and letting it loose on the axle in order to facilitate double sided V-belt
mounting in the grooves of the pulleys, and facilitate pre tensioning of the Vbelt
without dislocating the alternators.
A further object of the invention is to provide dual fixed flanges on the prime
movers axle with a detachable and slide able pulley in the center in order to
provide additional support to pulley for higher traction applications.
A further object of the invention is to provide a pulley fixing jig to slide the
double sided V-belt loaded pulley back to its mating flanges for fixing it with
long bolts.
A further object of the invention is to provide a pulley loading threaded holes
in the center space of the pulley to aid fixing jig to mount screw threads on
the pulley for pulling or pushing action.
A further object of the invention is to use the pre-existing belt tensioning
mechanism with the said detachable pulley.
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A further object of the invention is to provide the sliding carriage with
alternators below the bogie cross beam for medium and low power
applications.
A further object of the invention is to provide double sided V-belt tensioning
rollers on the inside or on the outside of the double sided V-belt and the
tensioning rollers could be placed either on top or below or at both the
locations of the double V-belts in between the drive and the driven pulleys.
With the above and other objectives in view, as will hereinafter appear,
various embodiments of the present invention are described hereunder.
SUMMARY OF THE INVENTION
According to an embodiment of the invention, An Improved mounting
arrangement for alternators in space constrained bogie of railway vehicles
and like transits and methods thereof, comprises; a dual alternators on the
upper side of the bogie crossbeam and positioned in such a manner, that
their respective driven pulleys, faces each other on same rotational axis and
towards the center of the axle of the drive pulley; providing additional
alternator stator and rotor length along the axis of rotation; thereby reducing
the overall diameter of the alternators and enabling it to be accommodated in
less vertical space; a slide able carriage mounted on the top of the bogie
crossbeam and holding the said alternators securely wherein the slide able
carriage could be adjusted and positioned with suitable screw mechanism to
align the alternators and provide suitable double sided V-belt tensioning. The
arrangement further including a detachable hub mounted hollow drive pulley
on the prime movers axle such that it could be loosened to accommodate
and facilitate the mounting and changing of the plurality double-V-belts. A
double V-belt tensioning arrangement for the alternator is done by mounting
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plurality rollers on the belts suitably placed on the double sided V-belts to
provide belt tensioning as required in day to day operations; Thereby
enabling the installation of conventional low cost alternator in space
constrained bogies.
According to another embodiment of the invention dual alternators are
provided with their respective pulleys facing each other along the axis of
rotation and firmly mounted on the bogies crossbeam.
According to another embodiment of the invention the length of the
alternators along the axis of rotation is increased and its diameter is
decreased to enable its accommodation in vertically space constrained
bogies.
According to another embodiment of the invention a sliding carriage with
firmly mounted alternators along with plurality screw and slot arrangement
are disposed, to adjust the carriage and alternators in x/y-axis thereby further
facilitating the belt alignment and its tensioning in space constrained bogies.
According to yet another embodiment of the invention the sliding carriage
along with firmly mounted dual or single alternator is securely mounted on
the top surface of the bogie crossbeam of the fiat bogie beneath the car-body
floor.
According to yet another embodiment of the invention alternators are
mounted on the top of the bogie’s crossbeam, below the car-body with
appropriately placed mounting brackets, guide slots along with matching
holes to facilitate the replacement of the alternators when defective or
loosening it in the events of V-belt changing.
8
According to yet another embodiment of the invention alternators a suitable
gap is provided in between the alternators respective pulleys facing each
other to facilitate loading of the plurality double sided V-belts and the said
pulleys are thereafter coupled together with a suitable coupler and flange
arrangement to further stabilize the alternator arrangement for high power
and vibratory environment.
According to yet another embodiment of the invention a plurality double sided
V-belts are disposed to drive the plurality pulleys along with a suitable belt
tensioning arrangement with plurality rollers pressing the double sided Vbelts
thereby maintaining belt tensioning in day to day activities.
According to yet another embodiment of the invention a hub type detachable
drive pulley is mounted on the axle, with plurality nuts on the side of the
pulley in circular arrangement and a fixed type, split mounted flange on the
prime movers axle, such that the pulley could be detached and rest its inner
surface on the axle in order to facilitate pre tensioning and loading of plurality
V-belts without dislocating the alternators.
According to yet another embodiment of the invention dual fixed flanges are
disposed on the prime movers axle with detachable and slide able pulley in
the center having plurality through holes along the axis of rotation and long
bolts tightening arrangement in order to provide additional support to pulley
for higher traction applications and also to facilitate pre tensioning and
loading of plurality V-belts without dislocating the alternators.
According to yet another embodiment of the invention a pulley fixing jig is
disposed to aid the loading of the drive pulley with plurality double sided Vbelts
such that the drive pulley could be slide suitably to and fro to its mating
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flanges for securing it with long bolts for the said in between fixed flanges
design or as hub mounted type design.
According to yet another embodiment of the invention a the drive pulley is
provided with a space in the center of the pulley having plurality loading
threaded holes, to aid fixing jig to mount its screw in the loading threads on
the pulley for easy pulling or positioning of the pulley with its mating holes of
the fixed flanges.
According to yet another embodiment of the invention the sliding carriage
with firmly mounted alternator could be disposed below the bogie cross beam
for medium and low power applications with single or dual alternators.
According to yet another embodiment of the invention is to provide double
sided V-belt tensioning rollers on the inside or on the outside of the double
sided V-belt and the tensioning rollers could be placed either on top or below
or at both the locations of the double V-belts, in between the drive and the
driven pulleys.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 shows a detailed top view of various components of the invention as
installed in the bogie.
Figure 2 show a detailed side view of various components of the invention as
installed in the bogie.
Figure 3 shows a detailed view of various components of the invention as
installed on the sliding carriage.
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Figure 4 shows a detailed view of the present invention with respect to hub
mounted detachable drive pulley on the axle.
Figure 5 shows a detailed view of the present invention with respect to
mounting of the drive pulley with dual fixed flanges on the axle.
Figure 6 shows a detailed view of the present invention with respect to
method for loading the pulley.
Figure 7 shows a detailed top view of the present invention showing
mounting of the alternators on the bogies crossbeam with quick change
arrangement.
Figure 8 shows a detailed top view of the present invention showing the
various elements of the present invention as placed in the railway bogie in
three dimensional view to aid further understanding of the invention.
For a better understanding of the embodiments of the invention and to show
how it may be performed, it will now be described in more detail with
reference to the accompanying drawings.
DETAILED DESCRIPTION OF THE INVENTION
The present invention can be better understood by reading the following
detailed description of some of the embodiments, with reference made to the
accompanying drawings. It will be understood that a particular system
embodying the invention is shown by way of illustration only and not as a
limitation of invention. The principles and features of this invention may be
employed in various numerous embodiments without departing from the
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scope of the invention. References are made to accompanying drawing in
which its novel feature and advantages will be apparent.
As can be seen in Figure 1, top view of the bogie, it shows the various
elements of the present invention as installed in the bogie. The bogies
crossbeam 12, is disposed with brackets to enable the mounting of
alternator carrier bead 101, along with the sliding carriage 1, which further
firmly supports the alternator-A 2 and alternator-B 3, with their respective
pulleys alternator-A pulley 3, and alternator-B pulley 4, facing each other
aligned in the axis of rotation. The drive pulley 8, carrying plurality double
sided V-belts 9, is mounted on the bogies axle 13. The plurality tensioning
rollers-A 7, and tensioning rollers-B 10, are appropriately positioned with their
respective adjustment brackets 6, and 11, such that the said tensioning
rollers could be pressed against the plurality double sided V-belts 9, and
maintain necessary belt tensioning forces as required to generate the
required power.
As can be seen in Figure 2, it shows the various elements of the present
invention as seen from the side view of the bogie. The side view of
alternators 15, is shown to be mounted on the bogies cross beam 12, along
with alternator carrier bed 101, firmly supported on a sliding carriage 1. The
support brackets 17, are part of alternators to firmly secure the alternators on
the said bed and the sliding carriage 1. The bottom side of the bogies cross
beam 12, is disposed with a plurality tensioning roller support bracket 21,
which further holds the slide-able plurality belt tensioning rollers 23, along
with a threaded guide and tensioning spring 30. The arrangement is also
disposed with a hex bolt type rotatable arrangement 22, at the end to
facilitate the forward and backward movement of the plurality belt tensioning
rollers 23. The axle 13, is mounted with the drive pulley 8, and plurality
double sided V-belts 9, to transfer the traction to the driven pulley 16, of the
alternators. The sliding carriage 1, is so designed to position the alternators
12
towards or away from the drive pulley and further aid in maintaining proper
belt tensioning and alignments.
As can be seen in Figure 3, it shows the various elements of the present
invention as seen from the front side of the bogie. The bogies crossbeam 12,
is disposed with plurality sliding carriage support brackets 19. The sliding
carriage support brackets 19, firmly grips the sliding carriage 1, along with
the alternator-A 2, and alternator-B 5. The sliding carriage 1, have
adjustment screws 32, to enable the positioning of the alternators 2, and 5, in
such a way that the alternator’s pulleys matches the drive pulley and also
maintain necessary belt tensioning and alignments.
As can be seen in Figure 4, it shows the various elements of the present
invention with respect to drive pulley arrangement. It comprises of a fixed
flange 37, which is required to be firmly mounted on the prime movers axle.
The fixed flange 37, is further divided into two equal split halves with split
flanges 44, along with plurality mounting holes 38, such that it could be tied
securely on the bogies axle at center hole 45. The fixed flange 37, is also
disposed with plurality mounting holes 39. The arrangement further consist of
hollow pulley ring 8, which is inserted on the axle and is disposed with
plurality nuts 42, at its one side such that this pulley could be securely fixed
with the matching holes on the fixed flange 37, with plurality bolts and split
pins 43. The pulley 8, is further disposed with center flat space 46,
containing plurality threaded holes 47, to facilitate the loading and holding of
the said pulley with plurality belts.
As can be seen in Figure 5, it shows the various elements of the present
invention with respect to drive pulley arrangement for generating higher
traction and power. The arrangement disposes two number identical fixed
flanges 48, and 53, on the either side of the detachable pulley 8. The fixed
flange 48 and 53, are further divided into two equal split halves with split
13
flanges 49, along with plurality mounting holes 50, such that it could be tied
securely on the bogies axle. The fixed flanges 48 and 53, contains a slideable
pulley 8, in the center which is in a ring shape pulley having plurality
through holes matched to be mated with the said fixed flanges holes. The
device uses plurality Long bolts 55, which could be inserted in the mated
holes from one end of the fixed flange 53, then the pulley 8, and then
towards the other side of the fixed flange 48, such that the pulley could be
securely fixed with plurality nuts 52. The arrangement facilitates V-belt
loading and tensioning in space constrained application as the pulley 8, could
be loosened to enable replacement and or pre tensioning of the V-belts.
As can be seen in Figure 6, it shows the various elements of the present
invention with respect to loading and pre belt tensioning of drive pulley
arrangement. The slide able pulley 8, can be seen at offset position 66, with
respect to its mated identical fixed flanges 67 and 65, and from the axle 13.
The pulley is disposed with center free circular space 63 containing plurality
threaded holes 64. A pulley fixing jig 68, shown in the inset comprises of a
bracket with two identical flange rests 70, supported with a support 71. The
flange rests 70, are suitably designed to fit the outer edges of the fixed flange
65 and 67, and threads 69 of the pulley fixing jig 68, is screwed on the
threaded holes 64, thereby any rotation of the threads 69, through its hex nut
72, pulls or pushes the pulley 8, towards or away from the fixed flanges 65
and 67. This device facilitates in bringing the mated holes of the pulley 8, as
the fixed flanges 65, and 67 together such that the pulley could be easily
fastened and the v-belts are brought to desirable pre tensioning. The pulley
fixing jig 68, comprises of a fixed ring 73 on the rotating shaft 74, such that
the fixed ring 73, enables a pulling or pushing action when the threads 69,
are rotated.
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As can be seen in Figure 7, it shows the various elements of the present
invention with respect to the placement of the alternators on the bogies cross
beam. An alternator carrier bed 101, is securely mounted on the top of the
bogies cross beam 12, through plurality brackets 19, which in turn are
securely welded or connected with the bogies cross beam 12. The alternator
carrier bed 101, comprises of mounting arrangement for the alternators 2 and
5, with their perspective pulleys facing each other and further comprising of
identical guide slots 76, 76-1, 78, 78-1, 79-1, 79-2, 79-3 and 79-4, to hold the
said alternators in predetermined position. The alternators are disposed with
fixed flanges carrying plurality holes 77, to enable secure fixing of the
alternators 2 and 5 on the alternator carrier bed 101. The alternator carrier
bed 101, could be securely fastened to the bogies cross beam 12, through its
welded supports 19 or on slide carriage as discussed previously in the figure
number 3. The said alternators respective pulleys 3 and 4 are provided with a
gap to facilitate loading of the plurality double sided V-belts and the said
pulleys are thereafter joined together with a suitable coupler and flange to
further stabilize the alternator arrangement.
As can be seen in Figure 8, it shows the various elements of the present
invention as placed in the railway bogie in three dimensional views to aid
further understanding of the invention. The pre-existing railway bogie 102,
comprise of a cross beam 12, as a part of bogie support structure. This cross
beam 12, is utilized to mount the alternators 2 and alternator 5, along with
alternator carrier bed 101 and or sliding carriage 1. A plurality belt tensioning
rollers 23, are positioned beneath the crossbeam in order to provide
adequate belt tensioning. A drive pulley 8, is mounted on the bogies axle 13,
to transmit the power to the alternators through double sided V-belts on the
pulleys.

I Claim:
1. An Improved mounting arrangement for alternators in space
constrained bogie of railway vehicles and like transit and Methods
thereof, comprising:
A dual alternator carrier bed (101) disposed with guide slots (76),
(76-1), (78), (78-1), (79-1), (79-2), (79-3) and (79-4) to accurately hold the
dual alternators (2) and (5) in predefined positions along with mounting
brackets and plurality holes (77) for firmly fixing the said alternators to the
said carrier bed. Plurality bogie crossbeam support brackets (19) firmly
attached and or welded with the bogies cross beam (12); thereby supporting
the alternator carrier bed (101) for fixed mounting.
a slide-able carriage (1) to further hold and fix the alternators
carrier bed (101) enabling the positioning and alignments of the said
mounted alternators with respect to the drive pulley(8) and aid mounting of
plurality double sided V-belts (9).
A plurality belt tensioning rollers (23) suitably mounted on the
bogie crossbeam (12) along with the said rollers position adjustment
mechanism to maintain desired tensioning on the plurality double sided Vbelts
(9).
the said plurality belt tensioning rollers (23) could be positioned on
the either sides of the double sided V-belts (9) and or on the plurality
locations on the surface of the said belts to maintain required tensioning.
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A drive pulley (8) mounted on the axle (13) with detachable hub type
arrangement consisting of fixed flange (37) comprising of split half brackets
(44) to mount it on the axle (13) firmly, a pulley hollow ring (8) with plurality
nuts (42); thereby enabling easy detachment of the said pulley in order to
facilitate loading of plurality double sided v-belts (9);
The drive pulley (8) further mounting arrangement for high power
output applications; whereby the two ends of the said pulley is supported with
two identical fixed flanges (48) and (53) disposed with mounting holes (50)
around its periphery, in between the said flanges the drive pulley ring (8) is
installed which is further disposed with plurality through holes mated with the
mounting holes (50) of the said flanges for fixing.
2. The device as claimed in any one of the preceding claims, wherein
dual alternators (5), (2) are provided with their respective pulleys
facing each other along the axis of rotation and firmly mounted on the
bogies crossbeam (12) on a combined mount, alternator carrier bed
(101).
3. The device as claimed in any one of the preceding claims, wherein the
length of the conventional alternators (5), (2) along the axis of rotation
is increased and its diameter is decreased to match the space
contours thereby enabling its accommodation in vertically space
constrained bogies.
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4. The device as claimed in any one of the preceding claims, wherein a
sliding carriage (1) with firmly mounted said alternators along with
plurality screw and slots, to adjust the carriage and alternators in x/yaxis
thereby further facilitating the belt alignment and its tensioning in
space constrained bogies.
5. The device as claimed in any one of the preceding claims, wherein the
sliding carriage (1) along with firmly mounted dual or single alternator
(5), (2) is securely mounted on the top surface of the bogie crossbeam
(12) of the fiat bogie with a suitable gap beneath the car-body floor
(14).
6. The device as claimed in any one of the preceding claims, wherein the
said alternators are mounted on the top of the bogie’s crossbeam (12),
below the car-body(14) with appropriately placed plurality mounting
brackets and guide slots (77) along with matching holes to facilitate
the replacement of the alternators when defective or loosening it in the
events of V-belt changing.
7. The device as claimed in any one of the preceding claims, wherein
plurality double sided V-belts (9) are disposed with a suitable belt
tensioning arrangement (104) with plurality rollers (23) pressing
against the plurality double sided V-belts (9) thereby maintaining belt
tensioning in day to day activities.
8. The device as claimed in any one of the preceding claims, wherein a
hub type detachable drive pulley (8) is mounted on the axle (13), with
plurality nuts (42) mounted in circular arrangement on one side of the
pulley and a fixed type, split mounted flange (37) on the prime movers
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axle (13), such that the pulley could be detached and its hollow inner
portion (40) is employed to facilitate pre tensioning and loading of
plurality V-belts without dislocating the alternators for low and medium
power application.
9. The device as claimed in any one of the preceding claims, wherein
dual fixed flanges (48), (53) are disposed on the prime movers axle
with detachable and slide able pulley (8) in between the said flanges,
having plurality matched through holes (103) and mounting holes (50)
on the outer ring of the pulley and the said flanges; whereby long bolts
(55) could be used to fix the said and thereby providing additional
support to pulley for higher traction and power applications and;
further facilitating pre tensioning and loading of plurality V-belts
without dislocating the said alternators.
10. The device as claimed in any one of the preceding claims, wherein a
pulley fixing jig (68) is disposed to aid the loading of the drive pulley
(8) with plurality double sided V-belts such that the said drive pulley
through holes (103) could be suitably positioned and matched to the
mounting holes (50) of the dual fixed flanges (65), (67) ; Thereby
enabling easy mounting and securing it with long bolts.
11. The device as claimed in any one of the preceding claims, wherein a
suitable gap is provided in between the alternators (5), (2) and their
respective pulleys (3), (4) facing each other to facilitate loading of the
plurality double sided V-belts and; the said pulleys are thereafter
coupled together with a suitable coupler and flange arrangement (105)
to further stabilize the alternator arrangement for high power and
vibratory environment.
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12. The device as claimed in any one of the preceding claims, wherein the
drive pulley (8) is disposed with circular space (63) in the center of the
pulley having plurality loading threaded holes (64), to aid the fixing jig
(68) mount its screw (69) in the loading threads (64) on the pulley for
easy positioning of the V-belt loaded pulley along with its mating holes
of the fixed flanges (65), (67).
13. The device as claimed in any one of the preceding claims, wherein a
sliding carriage (1) is provided which in turn have brackets to firmly
mount the alternator (2), (5) an the said carriage could be disposed on
top at angle or below the bogie cross beam for medium and low power
applications with single or dual said alternators.
14. The device as claimed in any one of the preceding claims, wherein the
double sided V-belt (9) is disposed with plurality belt tensioning
arrangements (104) along with plurality rollers (23) be positioned on
the inners side and or the outer side of the plurality double sided Vbelts
(9) and; the tensioning rollers (23) could further be suitably
placed in between the drive pulley (8) and the driven pulleys (16) on
the said belts top or bottom locations.
15. The device as claimed in any one of the preceding claims, wherein an
alternators carrier bed (101) is securely mounted on the top of the
bogies cross beam (12) through plurality brackets (19) which in turn
20
are securely welded and connected with the bogies cross beam (12).
The said carrier-bed, further comprises of mounting arrangement for
the alternators (2) and or (5), with their respective pulleys facing each
other and said carrier-bed further comprising of identical guide slots
(76) (76-1) (78) (78-1) (79-1) (79-2) (79-3) and (79-4) ; Thereby
facilitating the positioning said alternators in predetermined position
and; The said alternators are disposed with fixed flanges carrying
plurality holes (77) to enable secure fixing on the carrier bed (101).
The alternator carrier bed (101) could be securely fastened to the
bogies cross beam (12), through its welded supports (19) or to the
slide able carriage (1).
16. The device as claimed in any one of the preceding claims, wherein An
Improved mounting arrangement for alternators in space constrained
bogies of railway vehicles and like transits and methods thereof,
substantially as herein described and illustrated in the figure 1, figure
2, figure 3, figure 4, figure 5, figure 6, figure 7, and figure 8, of the
accompanied drawings.