FIELD OF INVENTION
The present invention, in general, relates to textile machinery and specifically to bobbin drive systems. Further, the present invention relates to textile machines like roving frames with modified drives to the bobbin to increase the flyer speeds at the same time to reduce the power loss in transmission and heat generated by the moving parts. More particularly, the present invention relates to a Bobbin drive system of textile machine.
DESCRIPTION OF RELATED ART
Figure 1 depicts the bobbin drive system in the prior art.
The existing flyer frames are used to draft the sliver material delivered by the draw frames wherein the sliver is incorporated with a slight twist and wound round a bobbin in the form of a roving which is subsequently converted in to yarn by the textile ring spinning machine. Typically each speed frame has a plurality of spinning stations arranged in a plurality of sections. Equal number of sliver cans as that of the spinning stations comprising sliver material delivered by the draw frame machine is arranged in a creel member and feed to the drafting arrangement where the sliver material is drafted which is subsequently feed to the flyer for deposition of the material in the form of roving on bobbins. Normally the bobbin is mounted on a drive means and the flyer is surrounds the bobbin and driven by the drive system of the machine. While the speed of the flyer is

maintained at a pre determined constant speed by the drive system, it is essential to adopt the speed of tlie bobbin according to the growing diameter of the bobbin. For this purpose differential gearing is adopted invariably. The drive is transmitted from the main motor (1) to differential gear box (3) through flat belt drive through pulleys (4,5) and Flat belt. Another input from a servo motor (2) is given to differential gear box (3) through timing belt pulleys (6,7) and timing belt. The out put of the differential gear box (3) is given to cardan shaft (10) through timing belt drive through pulleys (8,9) and timing belt. From the cardan shaft, drive is given to plurality of gear boxes (11). The gear boxes (11) convert the axis of the drive from horizontal to vertical i.e. 90deg directional change. From the gear boxes (11), drive is given to timing belt pulley (12). Bobbin rests on the timing belt pulley (12), which drives the Bobbin (13).
During bobbin build up, rotational speed of the bobbin and the traverse of th.e bobbin trough need to be adopted from layer to layer. The change over of every layer should be on a smooth curve. This is achieved by adopting the servo motor speed for each layer. This decremented value depends on the process parameters.
Normally the machine is constructed in number of sections, and each section is provided with one bobbin trough wherein the bobbin drive arrangement is housed. The bobbin troughs are made out of sheet metal. Drive is transmitted to gearboxes through connecting shafts. The adjacent gearboxes are seating on a different bobbin trough of sheet metal material. Also the bobbin troughs are

moving up and down continuously. This imposes limitation for ensuring the accurate alignment of all connecting shafts located at different sections. The misalignment leads to twisting of the connecting shafts and subsequent breakage.
LIMITATIONS
The current drive to the bobbin causes problems such as oil leakage and wear of the rotating parts at high flyer speeds. The cardan shaft also has inherent speed errors. In the present system, there is a Power loss due to drive transmission through shaft and gearboxes as well as heat generation.
In the existing system misalignment between sections is accumulated while going for more spindlage. It restricts the number of spindles.
SUMMARY OF THE INVENTION
The primary objective of the invention is to increase the flyer speeds at the same time reduce the power loss in transmission and heat generated by the moving parts.
This invention proposes a system by which the limitations of the current technologies are overcome and the above objective can be achieved by use of speed frame with improved bobbin drive arrangement.

The present invention relates to a bobbin drive system of textile machine comprising a main motor (1) for generating constant speed drive, a drive bracket assembly (14), flat belt pulley (4,5) and flat belt to transmit drive to said bracket assembly, a differential gear box (3), timing belt pulleys (15,16) to transmit drive to said differential gear box, a variable speed drive (2) to provide variable speed drive to the said differential gear box through the timing belt pulleys (6,7) and a timing belt, a gear box (17) to receive drive from the said differential gear box (3), a rotary ball spline (18), said gear box (17) convert the horizontal drive into vertical drive to drive the said rotary ball spline (18) which again drive the first idler shaft (19) through timing belt (20) and said idler shaft drives the timing belt pulley(12) on which bobbin (13) rest.
These and other objects, features and advantages of the present invention will become more apparent from the ensuing description of the invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 schematically illustrates the bobbin drive system of a known textile machine.
Figure 2 schematically illustrates the bobbin drive system of the textile machine according to the invention.
Figure 3 schematically illustrates the gearbox adopted to convert the horizontal

drive into vertical drive of the bobbin drive system of the textile machine according to the invention.
Figure 4 schematically illustrates the power transmission elements of the ball spline of the bobbin drive system of the textile machine according to the invention.
Figure 5 schematically illustrates another embodiment of the bobbin drive system of a textile machine according to the invention featuring conversion of horizontal drive into vertical drive using crossed V belt drive.
Figure 6 schematically illustrates the detail of conversion of horizontal drive into vertical drive using crossed V belt drive illustrated in figure 5.
DETAILED DESCRIPTION OF THE INVENTION
The preferred embodiments of the present invention will now be explained with reference to the accompanying drawings. It should be understood however that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. The following description and drawings are not to be construed as limiting the invention and numerous specific details are described to provide a thorough understanding of the present invention, as the basis for the claims and as a basis for teaching one skilled in the art how to make and/or use the invention. However in certain instances, well-known or conventional details are not described in order not to unnecessarily obscure the present invention in detail.

Ball splines are used to transmit the motion between one fixed drive element to another moveable driven element. In the present invention the drive from the
Timing Belt Pulley located in headstock, which is stationary, to the Timing Belt Pulley of the idler shaft located in the first bobbin trough, which is moving up and down.
The drive motors, the differential gearbox and the related drive elements are arranged in the head stock of the textile machine. Constant magnitude power is transmitted from the first drive (1), which may be for example a induction motor to drive bracket assembly (14) through flat belt pulleys (4, 5) and Flat belt. From the drive bracket assembly (14) power is transmitted to the differential gear box (3) through timing belt pulleys (15, 16). Another input to the differential gearbox being provided by a second drive (2) which is capable of providing variable magnitude power, for example a servo motor, a variable speed motor through timing belt pulleys (6, 7). The resultant output of the differential gear box (3) is transmitted to a gearbox (18) through timing belt pulleys (8, 9). Timing belt pulley (9) being mounted on the input shaft (17) of the gearbox (18). The said gearbox (18) converts the horizontal drive into vertical drive i.e. 90deg directional change. The output shaft (19) which is arranged perpendicular to the input shaft of the gear box (18) transmits power to the spline shaft (22a) of the rotary ball spline (22) through timing belt pulleys (20, 21) and the timing belt. The axis of the spline shaft (22a) being arranged approximately parallel to the out put shaft (19) of the gear box (18) and rotatably mounted by suitable mounting means. The spline shaft (22a) being rotatably supported in a outer hub (22b) of the rotary ball spline (22) and the outer

hub (22b) being mounted on a bracket (23) which is being connected to the bobbin trough (24).
The rotary motion of the spline shaft (22a) incorporates rotary motion to the pulley (22c) which is mounted on the outer ring of the rotary ball spline (22). The drive from the pulley (22c) is subsequently transmitted to the bobbin drive gear (12) and the bobbin (13) which is being drivingly connected to the bobbin drive gear (12).
The bobbin trough (24) being traversed up and down in a pre determined manner by the drive system of the machine to facilitate the bobbin built up. At the same time the rotary ball spline (22) transmits the required rotary motion to the bobbin through the spline shaft (22a) of the rotary ball spline (22) via the pulley (22c). The drive from the pulley (22c) is transmitted to the Idler shaft (25) through Timing belt (26). Thereupon the idler shaft (25), transmits the drive to the bobbins (13) attached to the first section through the bobbin drive gear (12) as well as the idler shaft (25) of the next section. In this fashion the drive from the rotary ball spline (22) is transmitted to the entire bobbins arranged on the textile machine.
The elimination of the individual gearboxes and the associated shafts and couplings results in minimized rotating parts and thus avoids oil leakage from the gear box and wear out of the parts.
In the proposed arrangement the task of changing the axis of the drive delivered

by the differential gear box from horizontal axis to vertical axis is conveniently done using a separate gearbox. Moreover in the proposed arrangement the plurality of gearboxes, employed for changing the axis of the drive from horizontal axis to vertical axis is eliminated. This greatly reduces the loss of power in transmission, and also reduces the heat generated.
The main advantages being,
1. For erecting gear box perfect alignment is needed, which requires a lot of time during assembly as well as erection. This time is saved.
2. Leads to modular concept.
3. Multiple section gearbox, shaft and coupling are eliminated. Consequently, oil leakage and wear out of rotating parts related to above can be eliminated
Alternate embodiment:
Figure 3 depicts the alternate embodiment in the proposed Bobbin drive system. In the proposed Bobbin drive system, V drive with crossed toothed belt is used in place of gearbox for converting horizontal drive in to vertical drive (90 degree directional change) is shown.
The resultant output of the differential gear box (3) is transmitted by timing belt through timing belt pulleys (8, 9). While timing belt pulley (9) being rigidly fitted on the rotatably mounted shaft (27) on its one end, the belt pulley (28) being rigidly mounted on its other end. Another shaft (29) which is arranged perpendicular to

the axis of the shaft (27) and being rotatably supported in a Housing (30). The shaft (29) carries belt pulleys (31) and (32) on its upper end and lower ends respectively. The shaft (29) being run by the crossed belt (33) in coordination with deflection pulleys (34). The crossed belt (33) may be a toothed belt or a flat belt. The pulley (32) being drivingly connected to the pulley (21) mounted on the ball spline (22a) and driven by belt (35). This arrangement facilitates the transmission of the resultant output of the differential gear box (3) to the ball spline (22a).
The advantage being V drive with crossed toothed belt is comparatively cost effective, further it contemplates reduction in power consumption and maintenance work / cost.
The main advantages being,
1. Speed error which is inherent property of the Cardan shaft can be eliminated whereby perfect speed ratio can be attained.
2. Multiple section gearbox, shaft and coupling can be eliminated. Consequently, oil leakage and wear out of rotating parts related to above can be eliminated.
3. Higher flyer speed can be achieved.
4. Rotation axis of the drive is changed before the first section, so that power lost and heat generated can be eliminated.
5. Drive can be extended even beyond 120 spindles

It will also be obvious to those skilled in the art that other construction and apparatuses can be derived from the combinations of the various methods and apparatuses of the present invention as taught by the description and the accompanying drawings and these shall also be considered within the scope of the present invention. Further, description of such combinations and variations is therefore omitted above.
Although the present invention has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications are possible and are apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims unless they depart therefrom.

WE CLAIM
1. A bobbin drive system of a textile machine comprising
a differential gear box arranged in the head stock of the textile machine to receive input drive from a first and a second drives, the first and the second drives being located in the head stock of the textile machine and drivingly connected to the said differential gear box , the bobbins being mounted on the respective bobbin drive gears which are arranged in the bobbin troughs and provided with means for drivingly connect the same with the said out put shaft of the differential gear box, characterized in that said means which drivingly connect the bobbin drive gears to the output drive of the differential gear box being a rotary ball spline (22).
2. A bobbin drive system of textile machine as claimed in claim 1, wherein the axis of the rotary ball spline (22) is arranged in a plane perpendicular to the out put shaft of the differential gearbox.
3. A bobbin drive system of textile machine as claimed in claim 1, wherein a gear box is drivingly connected to the output drive shaft of the differential gear box and the spline shaft (22a) of the rotary ball spline (22).
4. A bobbin drive system of textile machine as claimed in claim 1, wherein a V drive with crossed belt is drivingly connected to the output drive shaft of the differential gear box and the spline shaft (22a) of the rotary ball spline (22).

5. A bobbin drive system of textile machine as claimed in claims 1 and 4, wherein
the crossed belt of the V drive is toothed belt.
6. A bobbin drive system of textile machine as claimed in claims 1 and 4, wherein
the crossed belt of the V drive is flat belt.
7. A bobbin drive system of textile machine as claimed in claim 1, the bobbins
being driven by a plurality of idler shaft (25).
8. A bobbin drive system of textile machine as claimed in claim 1, wherein the
second drive is a servo motor.
9. A bobbin drive system of textile machine as claimed in claim 1, wherein the
second drive is a variable speed motor.
10. A bobbin drive system of textile machine such as herein described particularly
with reference to the figures 1 to 6 of the accompanying drawings.