This invention relates to a system for driving the draft rollers of textile draw frames.
Textile fibre is drafted when slivers pass through pairs of drafting rollers and top rollers provided in draw frames of textile machinery. The top rollers apply the required pressure to the fibres to be draftied. Conventionally, drafting is effected in two zones, namely the predrafting zone and the main dsafting zone. The surface speed of the drafting rollers have direct influence in achieving the desired drafting and therefore it is essential that the drafting rollers revolve at the desired speed without any variation. This particularly relevant in the case of high speed auto leveler draw frames.
At present drafting rollers are driven by using eiftier toothed belts or flat belts. Though toothed belt drive ensures positive drive, it is not always possible to achieve the required velocity ratio between the drafting rollers. This is particularty noticed when the required velocity ratio is in fraction.
Flat belt drive results in variation of surface speed of the drafting rollers mainly due to the inherent tendency of flat belts to slip during operation. This is especially noticed when the pulleys do not adequately envelop the belt.
The object of this invention is avoid the above referenced draw backs in drafting roller driving system.

The drive system consists of an mtermediate shaft drivable by a motor through gears. This shaft is provided with a pulley. An endless poly V belt connects the intermediate shaft to the front drafting roller through a pulley provided thereon. This poly V belt is also provided with a tenstoner to ensure proper tensioning of the belt. This arrangement transmit power from the intermediate shaft to the front drafting roller. Yet another pulley is mounted on the front drafting roller. The middle drafting roller also has pulley mounted thereon which lies in alignment with the pulley in the front drafting roller. A second endless poly V belt are provided with a tensioner connects the front drafting roller and the middle drafting roller. The driving area of all the endless belts is provided with multiple ribs. The driving and driven pulleys described herein above are also provided with multiple ribs on their outer periphery.
The mulitple endless poly V belt drive system described herein above transmits power from the intennediate shaft to the drafting rollers very uniformly thus avoiding the drawbacks of the existing system. It is possible to locate the tensioners at different setting distances to enable the drive system to be used in predrafting zones also.
A system for driving the drafting rollers of a textile draw frame according to this invention comprising a drivable intermediate shaft connected to the front drafting roller of said draw frame by means of a first endless poly V belt provided with ribbed inner surface through pulleys mounted on said intermediate shaft member and said front drafting roller, said front drafting roller being further connected to die middle drafting roller

of said draw frame by means of a second endless poly V belt, mounted on a set of pulleys provided on said front drafting roller and said middle drafting roller, each of said endless poly V belts being provided with tensionors.
This invention will now be described with reference to the single figure in the accompanying drawings.
The intermediate shaft is indicated by reference numeral (1). The pulley on this shaft is shown by numeral 2 and the endless poly V belt mounted thereon is indicated by reference numeral 6. The front drafting roller has a first pulley (4) movable on the front drafting roller through which the endless belt is connected to transmit power from the driven intermediate shaft. The front drafting roller has a second pulley (3) which aligns with a pulley (8) mounted on the middle drafting roller (9). An endless poly V belt (10) provided with a tensioner (11) connects the front roller with the middle roller for effective transmission of the drive to the middle roller. Reference numeral 7 shows the tensioner provided for the poly V belt connecting the intermediate shaft to, the front roller.
This drive system assures smooth drive of the drafting rollers resulting in better quality draft slivers.
The invention as described and claimed herein does not exclude obvious equivalents known to persons skilled in the art.

WE CLAIM:
1. A system for driving the drafting rollers of a textile draw frame comprising a drivable intermediate shaft connected to the front drafting roller of said draw frame by means of a first endless poly V belt provided with ribbed inner surface through pulleys mounted on said intermediate shaft member and said front drafting roller, said fronnt drafting roller being further connected to the middle drafting roller of said drawframe by means of a second endless poly V belt mounted on a set of pulleys provided on said front drafting roller and said middle roller, each of said endless belts being provided with tensioners.
2. The system as claimed in claim 1, wherein the outer surfaces of the pulleys are ribbed.
3. The system as claimed in claims 1 and 2, wherein the tensioners are adjustable.

4. A system for driving the drafting rollers of textile draw frames substantially as herein described and illustrated with reference to the accompanying drawing.