Claims:1. A transmission drive of main drive pulley in the locomotive engine comprising –
a universal shaft
a pulley fitted on the universal shaft to drive cooling blower of traction motor
a hub fixed in the pulley, fitted on the universal shaft to drive compressor and radiator fan of the locomotive engine,
characterised in that the cast steel hub and the cast iron pulley are fixed rigidly through a locking arrangement on the universal shaft by means of lock and key arrangement providing a sink fit wherein hub is made in such a way that power to the cooling blower of traction motor, air compressor and radiator fan are distributed separately from two different points thereby avoiding the concentric loading and providing suitable power transmission.

2. The transmission drive as claimed in claim 1, wherein a locking arrangement is done by high tensile bolts and nuts casted out of high tensile steel providing a rigid fixing of the hub and the pulley.

3. The transmission drive as claimed in claim 1, wherein the hub is made of cast steel and the pulley is made up of cast iron.
4. The transmission drive as claimed in claim 1, wherein the drive hub is fitted on universal shaft by key and lock nut through sink fit.
5. The transmission drive as claimed in claim 1, wherein a spacer is provided for fixing of universal shaft with the pulley and hub assembley.
6. The transmission drive as claimed in claim 1, wherein the power to the cooling blower of traction motor, air compressor and radiator fan are distributed separately from periphery and axially.
7. The transmission drive as claimed in claim 1, wherein driving power to the cooling blower of traction motor is provided through periphery of the pulley.
8. The transmission drive as claimed in claim 1, wherein driving power to air compressor and radiator fan is provided axially.
, Description:Field of Invention

The present invention relates to a transmission drive of main drive pulley, to drive traction motor, air compressor and radiator fan and more particularly to a modified transmission drive for providing variable loads on the transmission drive.

Background

In the Steel Plants, we have to move huge quantity of raw materials / finished goods comprising of incoming traffic (different raw materials etc.), outgoing traffic (finished/saleable steel products, pig iron, granulated slag, by products etc.) and in process traffic viz. cast Pig Iron, Mill scrap, Mill scale, Hot metal etc. For example at Vishakhapatnam Steel Plant itself 60-65 Metric Ton of such materials are transported from one place to another is above process. About 50% of this amount is transported by belt conveyors, 45% by rail transport and 5% by road.

The rail transport is handled by large number of wagons, and diesel locomotives to pull these wagons. Diesel locomotive mainly consists of Traction generator, diesel engine, and air compressor and radiator fan coupled to each other, running at 1100 RPM and producing 1100 Horse power. Hence all these parts are required to be rotated at perfect alignment. Diesel engine powers the main drive by universal shaft. Main drive pulley consists of two drive units at single point. 1) A pulley which drives cooling blower of traction motor and 2) The same pulley which drives air compressor and radiator fan. Both the air compressor and radiator fan dynamically rotate at variable speed as per the system requirement. Both are driven by cast iron pulley which is fitted on the compressor shaft by key and lock nut only. During running of engine main drive pulley is subjected to dynamic variable loads due to loading and unloading of air compressor and radiator fan. The gross of all three loads requires approximately 150 Horse power to drive these three sub-assemblies falling on a single point and main drive pulley which is made of cast iron is unable to withstand such loads. Hence main drive pulley is failing frequently and cutting power transmission to the total system resulting insufficient cooling of traction motors and cutting power transmission. Due to this failure transportation work goes to a halt and frequent repairs of transmission drive are required.

As frequent failures of main drive pulley of locomotive cannot be rectified in the existing system, it is affecting the engine crank shaft, compressor, radiator fan traction motors etc. This has cumulative effect on alignment of the engine block, compressor, and radiator fan and eddy current clutch etc.

Thus there is a need to provide a solution for the above identified problem to reduce failures to ensure proper and smooth functioning of locomotives.

Object of Invention

According to an embodiment of the present invention, a transmission drive assembly comprises:
a universal shaft
a pulley to drive cooling blower of traction motor
a hub to drive compressor and radiator fan
wherein hub is made in such a way that power to the cooling blower of traction motor, air compressor and radiator fan distributed separately from two different points.

According to further embodiment, a locking arrangement is provided for rigid fixing of the hub and the pulley firmly. The drive hub is fitted on compressor shaft by key and lock nut through sink fit. A spacer is provided for fixing of universal shaft flange. Driving power to the cooling blower of traction motor is provided through periphery of the pulley.

Brief description of drawings

Fig. 1 shows the transmission drive assembly as described in prior art.
Fig. 2 shows the pulley configuration according to prior art.
Fig. 3 shows transmission drive assembly according to present invention.
Fig.4 shows pulley configuration to present invention.

Detailed Description

For a thorough understanding of the present invention, reference is made to the following detailed description in connection with the above-mentioned drawings. Although the present invention is described with reference to exemplary embodiments, the present invention is not intended to be limited to the specific forms set forth herein.

Fig. 1 shows a transmission drive assembly (100) according to prior art. In locomotives the main engine (101) drives the main shaft (102). Main shaft (102) comprises a main drive pulley (103), which further comprises two drive units at single point.
1) A pulley (104) which drives cooling blower (105) of traction motor and;
2) The same pulley (104) drives air compressor (106) and radiator fan (not shown).

Both the air compressor (106) and radiator fan (not shown) dynamically rotate at variable speed as per the system requirement. Both are driven by cast iron pulley (104) which is fitted on the compressor shaft by key and lock nut only. During running of engine main drive pulley is subjected to dynamic variable loads due to loading and unloading of air compressor (106) and radiator fan. The diesel engine also drives the cooling blower (105) to cool the traction motor. The gross of all three loads requires 150 Horse power to drive these three sub assemblies falling on a single point and main drive pulley (103) which is made of cast iron and is unable to withstand this heavy load. Hence main drive pulley (103) is failing frequently and cutting power transmission to the total system. As frequent failures of main drive pulley of locomotive cannot be rectified in the existing system. It affects the engine crank shaft, compressor, radiator fan traction motors etc. This has cumulative effect on alignment of the engine block, compressor, and radiator fan and eddy current clutch. etc.,

Fig. 2 shows the pulley (104) configuration according to prior art. The cast iron pulley (104) of Single block directly fitted on the compressor shaft by key and lock nut as shown. The pulley (104) includes multiple V-grooves. The different components connected to this pulley are driven by V-belts. Hence all the components are driven by the only periphery of the pulley (104), the total load of both the blower (105) and the compressor (106) are much heavier. This heavier load causes the failure of the pulley (104).

Fig. 3 shows transmission drive assembly (200) according to present invention. According to present invention, main drive pulley (203) is separated in to two parts i.e. a cast steel hub (203A) and Cast iron pulley (203B) fitted on the compressor shaft through shrink fit. Due to introduction of the cast steel hub (203A), Cast iron pulley (203B) drives RTTM blower only by ‘V’ Belts. Thus the total load on the periphery of the pulley is greatly reduced. The cast steel hub (203A) drives total drive system and M20 HT bolts are used for fastening the pulley.

The cast steel hub (203A) is made in such a way that power to the cooling blower (105) of traction motor, air compressor (106), and radiator fan (107) distributed separately from two different points. One is peripherally i.e. from the V-grooves of the pulley (203A) and other is axially i.e. from cast steel hub (203A). This arrangement avoids concentric loading provides suitable power transmission. The cast steel hub (203A) is fitted on compressor shaft by key and lock nut through shrink fit. The distribution of load is perfectly balanced due to introduction of cast steel hub (203A).

To fix the cast steel hub (203A) a taper bore is provided inside the hub. In combination to that a suitable key way is also provided on the cast steel hub (203A). A suitable bore is also made on the pulley for power transmission to traction motor cooling system of Blower (105). Locking arrangement is provided for fixing of hub (203A) and pulley (203B) rigid firmly. Optionally a spacer can be also provided for fixing of universal shaft flange.

Fig.4 shows pulley configuration to present invention. According to present invention, main drive pulley (203) is separated in to two parts i.e. a cast steel hub (203A) and cast iron pulley (203B) as described with reference to Fig. 3. The cast iron pulley (203B) is fitted on the compressor shaft through shrink fit. Due to introduction of the cast steel hub (203A), Cast iron pulley (203B) drives RTTM blower only by ‘V’ Belts. Thus the total load on the periphery of the pulley is greatly reduced. The cast steel hub (203A) drives total drive system and M20 HT bolts are used for fastening the pulley.

The introduction of the cast steel hub (203A) ensures that the load on the pulley (203) is distributed thereby reducing heavy loads on the pulley (203).

It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but these are intended to cover the application or implementation without departing from the spirit or scope of the present invention. Further, it will nevertheless be understood that no limitation in the scope of the invention is thereby intended, such alterations and further modifications in the figures and such further applications of the principles of the invention as illustrated herein being contemplated as would normally occur to one skilled in the art to which the invention relates.