FILED OF THE INVENTION
The present invention relates to an improved gear-train arrangement with traction
alternator. More particularly, the present invention relates to an improved gear-train
arrangement coupled with a main gear attached to shaft of traction alternator which in
turn transmit power to the auxiliaries comprising one auxiliary generator, one exciter,
one power take off unit (PTU) and one idle gear assembly, adaptable to all types of
diesel electric loco.
BACK GRPUND OF THE INVENTION
In a locomotive the traction alternator is coupled to the diesel engine. The electrical
power generated by traction alternator is fed to tractor motor through control
equipments. Besides that power is also required to operate for starting of diesel Engine,
exciting of field of alternator, for lighting in locomotive and for charging battery. The
particular demand of power is meted out by auxiliary generators and exciter. While the
„locomotive is on running condition, the cooling of traction motor is accomplished though
a blower mounted on power take off unit. These auxiliary generators and a power take
off unit gets its drive from gear train arrangement which is a unique arrangement in the
alternator used for traction application.
A prior Art discloses, the power transmission from the generation shaft to its auxiliaries
is performed by a belt drive which comprising -V belts & pully with suitable grooves cut
into it on which V- belts operate. The disadvantages of V-belt drive (1) reduce service
life due to improper belt tensioning, (2) mismatching of belt lengths resulting in
transmission loses. (3). V-belts are also subjected to certain amount of creep, so the
velocity ratio required between driver and drive pully was not constant.

In addition, with the V-belt drive, a proper alignment of bearing is required with respect to one
another in different auxiliary generators, power take off unit and to main generator shaft since
misalignment of the bearing can also cause wobbling, vibration, excessive bearing wear and
result in premature failure.
An US Patent No. 5228355 entitled PTO unit for a transmission or the like including a lubrication
system operable only when the PTO is in operation which discloses a teaching that a PTO drive
shaft is connected to either a first drive or a second drive by means of a laterally shiftable gear
mounted on the drive shaft. That means when the gear of the drive shaft is connected to a first
drive during that period second drive is idle. Again when laterally shifting the gear of drive shaft
takes place then only second drive will be connected. When second drive is working first drive
connection will be idle.
Secondly, the lubricant oil catering to the teeth of gear is by means of a oil pump which is
connected to the second drive. So when the second drive is off, no lubricant oil will be catered.
Thirdly, the gear train arrangement described in US 5228355 is applicable for automotive
application.
A Japanese Patent No. JP 2004122976 entitled "Driving device of vehicle" which discloses a
teaching of the driving device comprises a pulley shaft, an auxiliary machinery driving shaft, a
sun gear, a pinion carrier, a ring rear, a planetary mechanism where the pulley shaft and the
auxiliary machinery driving shaft are connected to arbitrary two elements of them, a motor
connected to one remaining element, a direct connection clutch capable of coupling two or
more elements of the planetary mechanism and a one-way clutch capable of regulating the
rotation of the auxiliary machinery driving shaft in one direction. The planetary mechanism, the
motor, the direct connection clutch, and the auxiliary machinery driving shaft are coaxially
arranged in series, and a distribution component of the motor is arranged radially outside a
bearing for supporting a rotor shaft of the motor.
Here the teaching discloses that there is a clutch system to engage and disengage gears and
pinions as per requirement. The power transmission is applicable in automobile vehicles.
Another European Patent No. EP 1337412 entitled "Dual control hybrid engine-transmission unit
for a vehicle" which discloses a teaching of a locking unit connects, on command, the sun gear

to the casing of the auxiliary reduction gear unit, and a coupler connects, on command, the ring
gear to the sun gear. The power unit has a primary internal combustion engine, an output shaft
for transmitting the vehicle torque, and an electrical machine driving this output shaft. There is
an auxiliary reduction gear unit transmitting the torque of the primary motor on the exit shaft,
this epicycloidal gear unit having a ring gear driven by the primary IC engine, a satellite carrier
driving the output shaft, and a sun gear.
This patent teaches a gear train in automobile application and one gear capable of operating
from one driving gear on command.
OBJECTS OF THE INVENTION
It is therefore, an object of the present invention to propose an improved gear-train
arrangement coupled with a main gear attached to the shaft of traction alternator which
eliminates the disadvantages of prior art.
Another object of the present invention is to propose an improved gear-train arrangement
coupled with a main gear attached to the shaft of traction alternator which performs a positive
drive and maintains a constant speed ratio without any slippage.
A yet another object of the present invention is to propose an improved gear-train arrangement
coupled with a main gear attached to the shaft of traction alternator which help to drive
compactly using minimum centre distance causing reduction in size of alternator.
A further object of the present invention is to propose an improved gear-train arrangement
coupled with a main gear attached to the shaft of traction alternator which operate with high
efficiency, and reliable in servicing and simple in operation.
A still further object of the present invention is to propose an improved gear-train arrangement
coupled with a main gear attached to the shaft of traction alternator which is inexpensive in
maintenance due to proper lubrication arrangement of gear and pinions by providing a sump
containing lubricated oil at a certain level.

A yet further object of the present invention is to propose an improved gear-train arrangement
coupled with a main gear attached to the shaft of traction alternator which provides gear drive
for longest service life as compared to V-belt drives.
SUMMARY OF THE INVENTION
The present invention provides with a gear train in traction alternator for diesel electric loco for
transmission of rotary motion to auxiliaries comprising a bull gear attached to an extended shaft
of traction alternator and a gear case comprises an assembly of plurality of gears coupled with
the bull gear and one sump containing lubricant oil and an oil filler tube hole characterized in
that the bull gear which transmit the power to the auxiliaries through pinion during rotation
wherein a part of the idler gear is immersed in the lubricant oil of sump which in turn supplies
the lubricant oil to all the pinions while in rotation wherein the gear case is provided with a hole
for dip stick for measuring oil level.
The gear case has one opening at back end and four openings on the front face end. At first, a
bull gear is shrink fitted on the extended part of the alternator shaft and then back face end of
gear case is fixed up with the traction alternator with extended shaft of alternator with bull gear
mounted projects through the back face opening in the gear case. Thereafter, one by one
auxiliary unit (i.e. 1 no. auxiliary generator, 1 no. exciter, 1 no. power take off unit and 1 no.
assembly) idle gear are assembled from the four openings of the front face end of gear case, in
such a way that the projected pinions of all auxiliaries mesh with the bull gear. The front face of
gear is completely sealed by these auxiliaries with proper sealing arrangement.
In gear case, the distance between the two end faces and center to center distance between all
the openings of the gear case are maintained within very close tolerance.
To achieve the rated speed of auxiliaries, number of teeth on bull gear to number of teeth of
auxiliaries pinions are selected.

While the traction alternator in running condition, bull gear rotates and transmit the
rotary motion to pinions of auxiliaries. During this operation lubrication of gear train is
achieved by splash lubrication. At the bottom of gear case, a sump is provided which
contain gear oil upto a predermined level and inspected off and on by means of a dip
stick. Teeths of the idler gear are partially dipped inside oil and when the gear train
operates, this oil is passed on the teeths of bull gear and pinions thus providing on
effective lubrication.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
Fig-1- Shows a schematic diagram of prior Art showing arrangement of pulleys and v-
Belt.
Fig-2- Shows a schematic diagram showing the gear train of a traction alternator with
gear case and oil lubricant therein.
Fig-3- Shows a schematic diagram of engine alternator Assembly.
Fig-4- Shows a schematic diagram of detail assembly of auxiliary Equipment with gear.
Train of Fig-2.
Fig-4A- Showing schematic diagram of power of take unit along with PTU pinion.
BRIEF DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION
As shown in fig-2- The improved gear train arrangement comprises a gear case (1)
which contains a main bull gear (2) attached to the shaft of the Traction alternator,
coupled with a pinion of power Take off unit (3), and a pinion of auxiliary generator (4)
and a pinion of exciter (5) and a gear of idler assembly (6) which constitute the total

gear assembly of the gear-train. The back face end of the gear case (1) is provided
with a single hole, through which the extended shaft of Traction alternator projects and
the Back face end is fastened with the body (end shield) of the alternator. Front face
end is provided with four holes to insert the four pinions of auxiliaries. These holes are
completely sealed by auxiliaries with proper sealing arrangement. The gear case is also
provided two side holes, one for pouring lubricant oil through oil filler tube (7) and the
other is for dip stick (8) for inspection of oil level. The gear case further provided a
sump (9) at the bottom to cat as reservoir of lubricant oil (10). When the main bull
gear (2) rotates the power transmission to all pinions (3, 4, 5) and idler gear (6) and
also start to rotate simultaneously. Part of idler gear (6) is immersed in lubricant oil
(10) and during rotation lubricant oil (10) splashes to the main bull gear (2) and so on
to other pinions. The quantity and level of lubricant oil (10) is inspected off and on
through a dip stick (8) inserted there in.
Fig-3 shows - The bull gear (2) mounted with the main shaft (12) of alternator (22)
and an assembly pinions of exciter (23), Auxiliary generator (24) with the bull gear (2)
and arrangement of mounting of alternator (22) with diesel engine (21).
Fig-4- Shows a schematic diagram of detail assembly of auxiliary equipment of fig-(2)-
the main bull gear (2) coupled with the pinion (5) of exciter (23) and a gear (6) of idler
Assembly (14).
Fig-4 (A)- Showing a sectional view of power take off unit (11) along with its pinion
(15).

WE CLAIM
1. A gear-train in traction alternator for diesel electric loco for transmission of rotary
motion to auxiliaries comprising:
- a bull gear (2) attached to an extended shaft of traction alternator;
- a gear case (1) comprises an assembly of plurality of gears (3,4,5,6) coupled
with the bull gear (2) and one sump (9) containing lubricant oil and an oil filler
tube hole;
- characterised in that the bull gear which transmit the power to the auxiliaries
through pinion (3,4,5) during rotation wherein a part of the idler gear is
immersed in the lubricant oil (10) of sump (9) which in turn supplies the
lubricant oil to all the pinions while in rotation wherein the gear case is provided
with a hole for dip stick for measuring oil level.
2. The gear train in traction alternator for diesel electric loco as claimed in claim 1
wherein the lubricant oil is poured through oil filler tube hole (7).

3. The gear train in traction alternator for diesel electric loco for transmission of
rotary motion to auxiliaries as substantially described therein with reference to
accompanying drawings.

The present invention relates to a gear train in traction alternator for diesel electric loco
for transmission of rotary motion to auxiliaries comprising a bull gear (2) attached to an
extended shaft of traction alternator and a gear case (1) comprises an assembly of
plurality of gears (3,4,5,6) coupled with the bull gear (2) and one sump (9) containing
lubricant oil and an oil filler tube hole characterized in that the bull gear which transmit
the power to the auxiliaries through pinion (3,4,5) during rotation wherein a part of the
idler gear is immersed in the lubricant oil (10) of sump (9) which in turn supplies the
lubricant oil to all the pinions while in rotation wherein the gear case is provided with a
hole for dip stick for measuring oil level.