Title of Invention

DEVELOPMENT OF A COMMON , 211 KW, DC TRACTION MOTOR WITH TAPER ROLLER SUSPENSION BEARING ARRANGEMENT FOR BOTH METER GAUGE & CAPE GAUGE DIESEL ELECTRIC LOCOMOTIVE APPLICATION

Abstract A common DC traction motor for both meter gauge and cape gauge Diesel- electric locomotives comprising a high permeability steel magnet frame (19), an armature having its core assembled on the shaft (26), the armature core having lap wound conductors connected to a copper commutator, a brush gear having four brush arms positioned symmetrically around the commutator, the shaft (26) being connected to the locomotive axle through a single reduction gear unit for transmission of power, the nose of the motor being supported in the bogie with resilient rubber-sheet sandwitch mounting, characterized in that the motor is dimensioned for both meter gauge and cape gauge applications.
Full Text (2)
Filed of invention:
The present invention relates to the field of diesel-electric locomotive in general
and to traction motors with taper roller suspension bearings such locomotives used in
haulage of meter gauge and cape gauge trains in particular.
Background and prior art:
At present, Diesel-electric locomotives for meter gauge and cape gauge use the
proven and advanced DC-Dc drive technology. Such locomotives one equipped with 6
DC series traction motors per locomotives. However, Diesel-electric locomotives for
meter gauge and cape gauge applications have different traction motors. There is no
common DC traction motor for both meter gauge and cape gauge locomotives in the
prior art.
The present invention seeks to overcome this drawback of the prior art.
Objects of the invention:
It is an object of the invention to provide a common DC traction motor which can
be fitted to a meter gauge as well as to a cape gauge Diesel-electric locomotive.
Another object of the invention is to provide considerable savings for inventory for any
railway network using both meter gauge and cape gauge locomotives.
A further objective of the invention is to provide DC traction motors with taper roller
suspension bearings with less maintenance demands, resulting in higher locomotive
availability and lower maintenance costs.

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Description of the invention:
The need for Diesel-electric locomotives having lower maintenance demands is
well known. To meet this requirement, the applicant has developed a series DC traction
motor with taper roller suspension bearing arrangement, details of which are disclosed
hereunder. The series DC traction motor in accordance with the present invention is a
common traction motor which can be used to drive either a meter gauge or a cape
gauge Diesel-electric locomotive.
The invention as disclosed hereunder refers to an exemplary embodiment. However
then can be several other embodiments of the invention, all of which one dumed
covered by this specification.
The invention will be described in details with the help of the following accompanying
drawings:
Brief description of the accompanying drawings:
Fig. 1 shows a longitudinal sectional view of the traction motor according to the
invention.
Fig. 2 shows the salient features of the motor.
DETAILED DESCRIPTION OF THE REFFERED EMBODIMENT
Magnet Frame:
The high permeability steel magnet frame (19) is machined to ensure alignment of
the end shields (28), pole bores and axle ways. The nose of the motor is supported in
the bogie with resilient rubber-steel sandwich mounting. The end shields (28) are

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spigotted into frame with slight interference fit and held in position by means of bolts
suitably locked. This method of mounting ensures that the fit between the end shield
and the frame can withstand all the heavy jerks and vibration from the railway tracks
and remains tight in service. Roller bearings are provided and labyrinths are formed to
prevent the escape of lubricating grease or the entry of dirt or moisture. Overall length
has been optimized to meet the requirement of meter gauge and cape gauge fitment.
The frame has been specially modified on the axleway side to accommodate the flanges
of the suspension tube assembly has to be accommodated on the locomotive axle within
the two road wheel hubs of the locomotive.
Armature:
The armature core is built from electrical quality low loss sheet steel laminations
insulated from each other and assembled on the shaft (26) with interference fit and
consolidated under pressure. The laminations are held together between endplates,
fitted on the shaft machined from nickel-chromium-molybdenum steel bar hardened &
tempered.
The armature is lap wound. The armature conductors are insulated with Kapton and
mica based Class "H" Insulation system. The coils are held down in the core slots with
epoxy glass laminated slot wedges, and Res-l-glass bands retain in the end portions of
the coils. The wound armature is finally vacuum pressure impregnated in solvent less
polyesterimide varnish. Armature end plate is redesigned with solid base plate and vent
holes aligned with the vent holes of the core assembly, for better cooling and strength.

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Epoxy glass slot wedges are provided for extra strength. Special commuter hub
designed for increased ventilation.
Commutator:
The commutator is of arch bound construction. The copper segments are made from
hard drawn silver bearing copper and risers integral with segments are slotted to receive
the armature coil leads. The armature coil leads are finally TIG welded to commutator
risers.
The copper segments which are insulated from each other with the micanite segments,
are held together with the Steel "V" rings, insulated with the moulded micanite V-rings.
The exposed surface of the commutator front micanite v-ring is covered with PTFE bush
to obtain high creepage and for ease in maintenance. Arcing horns are provided to
minimze the damage to the commutator and brush gear in the event of flashover.
Poles and Field Coils:
The poles are built up from steel laminations riveted together. The main field coils
(18) are made of copper strap wound on flat, whereas the compole coils are edge
wound. The coils are insulated with Class "H" insulating materials and vacuum pressure
impregnated in solventless polyesterimide varnish.
Brush Gear:
There are four brush arms, each carrying a brush holder with two carbon brushes.
Twin-stud insulators secure brush holders. PTFE bushes are mounted on the stud
insulators in between each portion and the brush holder provides a creepage surface for
ease in cleaning

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Gears and Gearcases:
The transmission to the locomotive axle consists of a single reduction gear unit, the
pinion (27) of which is shrink-fit on to the motor armature shaft (26) and the gear is
mounted directly on the locomotive axle.
The gear is housed in a gearcase (25) mounted on the motor which is made in two
halves bolted together. The joint between the halves has an overlap and felt wipers are
also provided to prevent contamination of the gear lubricant with dirt or moisture.
The new design of gear and pinion set is with 18:93 gear ratio for higher haulage
capacity. Gear case mounting has been modified. Top gearcase mounting has been
changed from horizontal position to vertical position for higher rigidity of fitment of
gearcase on traction motor. Opening on motor end of gearcase has been increased to
accommodated the enclosure.
Axle Suspension Bearings:
Locomotive axle is supported on an axle suspension-bearing unit (32,33) consisting
of taper roller bearings at the ends housed in suspension tube, which is bolted to the
traction motor magnet frame. Suspension tube requires less maintenance during service.
Armature Bearings:
The bearing assemblies (32,33) are of sealed type provided with adequate
labyrinths to avoid the contamination of the lubricating grease with dirt, moisture and
cardium compound.

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VENTILATION:
The forced ventilation is from a ducting system on the locomotive connected to the
motor through flexible bellows at the commutator end of the frame.
The cooling air flows in two parallel paths, one under the commutator and though
armature core ducts and the other along the outside of the armature and between the
field coils and escape to the atmosphere through the openings provided on the pinion
end of the frame.
The traction motor according to the invention, whose constructional features are
described above, is suitable
DETAILED DESCRIPTION OF THE INVENTION:
For meter gauge & cape gauge diesel electric locomotive for goods, mixed traffic
and passenger traffic. It is a DC series wound, four pole, and forced ventilated traction
motor suitable for axle mounting on taper roller suspension bearings. It is supported on
the nose by a resilient suspension unit. It complies with IEC-60349: 2001/IEEE-l 1:1982.
The invention provides undermentioned advantages over the prior art.
1. Taper roller suspension bearings provided is bother than sleeve type journal
bearings of prior art as they have less maintenance resulting in higher availability
of locomotives and more reliability.
2. Grease lubrication of axle bearings provided in the invention have very much
longer relubrication period of six months compared to one month in the prior art.

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3. New gear train design with increased gear ratio provides about 13.5% more
power output compared to motors for similar application in the prior art.
4. The DC traction motor in accordance with the invention is a common motor for
both meter gauge and cape gauge applications. Such a motor is entirely new,
and is not known in prior art. It offers immense versatility and flexibility.

A common DC traction motor for both meter gauge and cape gauge Diesel-
electric locomotives comprising a high permeability steel magnet frame (19), an
armature having its core assembled on the shaft (26), the armature core having
lap wound conductors connected to a copper commutator, a brush gear having
four brush arms positioned symmetrically around the commutator, the shaft (26)
being connected to the locomotive axle through a single reduction gear unit for
transmission of power, the nose of the motor being supported in the bogie with
resilient rubber-sheet sandwitch mounting, characterized in that the motor is
dimensioned for both meter gauge and cape gauge applications.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=gTajnuXB9CvjjMeJNZZ0tw==&loc=wDBSZCsAt7zoiVrqcFJsRw==


Patent Number 268883
Indian Patent Application Number 537/KOL/2008
PG Journal Number 39/2015
Publication Date 25-Sep-2015
Grant Date 21-Sep-2015
Date of Filing 18-Mar-2008
Name of Patentee BHARAT HEAVY ELECTRICALS LIMITED,
Applicant Address REGIONAL OPERATIONS DIVISION (ROD), PLOT NO: 9/1, DJ BLOCK 3RD FLOOR, KARUNAMOYEE, SALT LAKE CITY, KOLKATA-700091, HAVING ITS REGISTERED OFFICE AT BHEL HOUSE, SIRI FORT, NEW DELHI-110049
Inventors:
# Inventor's Name Inventor's Address
1 NARESH SINGH NA
2 SANJAY KUMAR YADAV NA
PCT International Classification Number B60L15/04; H02P7/06; B60L15/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA