Title of Invention

A RING SPINNING FRAME

Abstract

A ring spinning frame having double drafting zones comprising: a first top conductor (TI) for feeding sliver to a pair of primary zone retaining and pressing rollers (R1, P1); a lattice gill primary drafting zone (D1) through which the sliver is drawn by a pair of delivery and pressing rollers (DL, DP) to a second top conductor (T2) form which the sliver is passed to a secondary apron tumbler roller drafting zone (D2) by a pair of retaining and pressing rollers (R2, P2), and a pair of drawing and pressing rollers (DR, DP) lfor drawing the sliver from the secondary drafting zone over a stop motion feeler (SM) onto a spindle (P).

Full Text

The present invention relates to a ring spinning frame having double drafting zones comprising an open/intersecting lattice gill primary drafting and an apron-and-tumbler roller /apron and pressure plate secondary drafting. This invention enables convention of a 4.25", 4.75" or 5.50" pitch Slip draft flyer spinning frame or Apron draft spinning frame into ring spinning frame of said double drafting zones. Such convert ion enables spinning of lighter counts down to 3 lbs per spangle at higher speeds and to obtain bigger yarn packages than with the existing machines. In the existing system, jute stiver, normally below 150 lbs per spangle is fed from a sliver can through a top conductor. The stiver then passes between a retaining roller and a retaining pressing roller. The sliver is thereafter passed through a conductor over a breast plate. The sliver then moves between a fluted roller and an idler roller and then is drawn through the nip between a drawing roller and a pressing roller. The sliver then presses over a stop motion feeler onto a wharve. The sliver is then taken up by a flyer. Due to the difference in speeds and rotation of the flyer, the sliver, which is already drawn thin by the action of draft caused by the difference of speed between the retaining roller and the drawing roller, is twisted and formed into yarn. The yarn gets wound onto a bobbin mounted on a stationary spindle (also called dead spindle) and bobbin carrier. In this system, the flyer is moved by the drive through wharve and bobbin, i.e., the yarn package rotates and also moves up-and-down due to the up-and-down movement of bobbin rails. The bobbin rails are mounted on a lifter bracket which actually moves up and down to build the yarn package. Spare bobbin rail with dead spindle, bobbin carrier and bobbin is provided so that the spare set can be moved in position once the building-up of the bobbin on the wharve is completed. The yarn package made by this system is very small and the count range is about 6-12 lbs. It has got the following disadvantages. 1. Speed limitation -max. speed is less than 4000 RPM and that too for a medium count of 8 lbs yarn. 2. Cannot spin finer count of yarn below 6 .lbs economically. 3. Cannot spin from higher sliver weight requiring more back process machinery and requisite labour, power, etc. 4. Drafting system is inadequate for processing high quality yarn and blends. 5. Yarn package is too small requiring frequent doffing and incurring corresponding losses, in the spinning production as well as subsequent winding process. 6. Low production and hence more number of spinnings required for a given production involving more number of hands (man-days). 7. The yarn quality usually falls short of the standard required for modern high speed loom operation. Jute industry is more than 100 years old and has been playing a vital role in the economy of West Bengal and Bangladesh. But the industry is facing high manufacturing costs, mainly due to low productivity. One major reason for this is the use of antiquated machinery with low productivity and as a result high cost of labour engaged. In contrast, synthetic substitutes for packaging, bulk handling means etc have proved to be much cheaper and attractive. Jute mills in Europe closed down on account of high labour costs. As a result, the prospects of jute industry in India and Bangladesh brightened up. But Indian jute mills found it difficult to meet the stringent quality requirements of European weavers with the existing machines. To compensate for increase in labour costs, the mills resorted to cost-cutting measures which deteriorated machinery as well as quality. Jute industry cannot afford to invest in new machinery. Today the jute industry needs to increase productivity and quality with less expenditure on labour per ton of product and less expenditure on energy. It also requires to acquire capability to cater to wider range of product and versatility of the emerging market. The machinery and processes to be developed should be cost-effective and should not call for heavy investments. In order to convert the existing system to cater to the present day needs of the industry, the present invention has the object of modifying the existing system described above. Accordingly, the present invention provides a ring spinning frame having double drafting zones comprising: a first top conductor for feeding sliver from a sliver can; a primary zone retaining roller and a primary zone retaining pressing roller receiving sliver from said top conductor; a lattice gill primary drafting zone over which the sliver from the primary zone retaining and pressing rollers is drawn by a primary zone delivery roller anq a delivery pressing roller; a second top conductor downstream of the delivery and pressing rollers receiving the sliver therefrom; a retaining roller and a retaining pressing roller through which the sliver from the second top conductor passes; a secondary apron tumbler roller drafting zone downstream of said retaining and pressing rollers on which said sliver passes; and a drawing roller and a drawing pressing roller for drawing the sliver from the secondary drafting zone over a stop motion feeler onto a spindle mounted on a flyer and driven by a cylinder, a bobbin or pirm for winding the yarn being mounted on the spindle. The advantages of the present invention are as follows: 1. Increase in operating spindle speed by 1.5 times. 2. Capability to produce lighter counts i.e. upto 3 lbs yarns. 3. Increase in the yarn range from 3 to 10 lbs per spangle. 4. Increase in the yarn package by 1.5 times. 5. Capability to spin blended fibre. 6. Reduction/elimination of one back process of the preparatory system. 7. Reduction of number of machines for a given production per day. 8. Reduction in the electricity bill. 9. Saving of space (floor area). 10. Saving in winding. 11. Reduced labour cost (wages)/man-days per ton. 12. Adaptation of "ring spinning technology/features in the existing flyer spinning machine" by means of: a) using same flyer rail of existing machine. b) using same roller stands and existing rollers for drafting system for the two zonal drafting. c) using same drive arrangement of existing machine. d) using same arrangement of lifting/building mechanism of the existing machine. e) using same sliver- stop motion system of the existing machine. f) using same tape drive system of existing wharves for driving live spindles. The invention will now be described with reference to the accompanying drawings wherein -Fig. 1 is a line diagram of the existing slip drafting system; Fig. 2 is a line diagram of the system of Fig. 1 incorporating the modification of the present invention; Fig. 3 shows alternatively secondary drafting zone of the system shown in Fig. 2; Fig. 4 shows the spinning tube used in the system of Fig. 2; Fig. 5 shows the bobbin used in the system of Fig. 2; Fig. 6 shows a sketch of an apron draft jute spinning frame converted into a ring spinning frame according to the present invention; and Fig. 7 shows the system of Fig. 6. Fig. 8 shows roller stand rail. From Fig. 1, it can be seen that jute sliver (S), normally below 150 lbs per spangle, is fed from a sliver can (C) through a top conductor T2 between a retaining roller (R2) and a retaining pressing roller (P2). The sliver then passes through a conductor (T3) over a breast plate (which is usually convex shaped) (BP) where the sliver is drafted and drawn by a drawing roller (DR) and a pressing roller (DP). The sliver then asses over a stop motion feeler (SM) onto a wharve (W) so that it is taken up by a flyer (F). Due to the difference between speeds and rotation of the flyer, the sliver which is already very thin due to the drafting action as a result of difference in speed between the retaining roller (R2) and the drawing roller (DR), gets twisted and formed into yarn. The yarn gets wound onto a bobbin (P) which is placed on a stationary spindle (also called dead spindle because it is not live) and a bobbin carrier. The dead spindle is mounted on a flyer rail (FR) driven by a cylinder (CY). The bobbin is mounted on a bobbin rail (BR). Bobbin rails are placed on a lifter bracket (LB) which moves up and down for building-up the yarn package on the bobbin (P). Spare sets of bobbin rails fitted with dead spindles, bobbin carriers and bobbins are kept ready so that a fresh set can be put in position once the bobbin being wound is full with yarn. The flyer (F) moves by the drive through wharve and the bobbin, i.e., the yarn package rotates and moves up and down by up-and-down movement of the bobbin rail (BR). The yarn package obtained is small and the count range is 6 to 12 lbs. This system is inadequate for processing high quality yarn and blends which is the long felt need of the industry. The improved system of the present invention comprises a lattice gill primary drafting zone (D1) and a secondary apron tumbler roller drafting zone (D2) as can be seen from Fig. 2. The sliver (S) from sliver can (C) is passed through a first top conductor (T1) between primary zone retaining roller (R1) and a primary zone pressing roller (P1) into a lattice gill primary drafting zone (01) from which the sliver is drawn by a primary zone delivery roller (OL) and delivery pressing roller (OP) into a second top conductor (T2) from where sliver moves, as explained with reference to the Fig. 1, through the retaining roller (R2) and retaining pressing roller (P2). The sliver from the retaining rollers (R2, P2) passes over a secondary apron and tumbler roller drafting zone (02) and is them drawn out by the drawing roller (OR) and drawing pressing roller (OP) as explained with reference to Fig. 1 and then the sliver passes over the stop motion feeler (SM), a spindle crown (SC), ring rail (RL), and ring traveller (RT) shown in Fig. 2. The spindle (P) is mounted on the flyer rail (FR) and driven by cylinder (CY) as explained with reference to Fig. 1. The package (P) can be built on flanged bobbins or on sectional built pirns. The roller stand (RS) is positioned on a roller stand rail (RSR). The roller stand rail "RSR" of fig 2 is one of the vital component without which the conversion of existing machine will certainly be very difficult, hence it may please be properly highlighted for necessary protection. Although, ideally it should be like angle or "L" shaped cross section one can use slightly different shape. This rail is shown in Fig.B. In the slip draft spinning frame converted into ring spinning frame of the present invention, the existing apron plate (AP) and apron pressure plate (API) drafting zone having a rubber apron RA can be retained as shown in Fig. 3 instead of apron and tumbler roller mechanism for the secondary drafting zone. The building of the package in this converted Ring Spinning Frame can be either a straight build, i.e. Traverse motion moves up and down each time to the full length of the bobbin. Alternatively, the traverse motion will move only a part of the bobbin length each time and will shift gradually upwards ultimately covering the full length of the package. In other words this is a sectional build. For the full length build the package will be in flanged bobbin where as in sectional build the package will be in spinning tube or pirns. The advantage of straight build i.e. bobbin is that it allows doffing without having to stop the machine. This saves a good amount of down time/loss. For the bobbin package, the traverse length will be slightly lower. (Figs. 4 and 5). The existing lifter brackets have to be suitably modified. The mechanism and components for spindle drive provided in the existing slip drafting machine will be used in the ring spinning frame of the machine. In the case of the Apron Draft Spinning frame converted into ring spinning frame, the apron and pressure plate drafting zone (APD) is added. Only the lattice gill primary drafting zone described with reference to Fig. 2 will be added. A licking roller (LR) with water and suitable adhesive solution in a trough (TR) will be incorporated to control the hairiness which is a bad element of jute yarn. (Fig. 6). This can be provided in secondary drafting zone or the apron and pressure plate drafting zone in an apron shaft spinning frame converted into ring spinning frame. The pirns (P1) used for sectional building is also shown in Fig. 6. In Fig. 7, the existing apron drafting spinning frame differs from the draft spinning frame of Fig. 6 only in the drafting zone. Builder and package are the same. Since the other details of the apron draft spinning frame converted into ring spinning frame according to the invention, other details described with reference to Figs. 1 and 2 have not been repeated. Comparative Existing Flyer Converted Ring Features Spinning Spinning pitch of Spindles 4.1/4" 4.1/4" (or 4.3/4" or 51/2") (or 4.3/4" or 51/2") No. of Spindles 100 (96 or 80) 100 (96 or 80) Type of Spindle Dead Live Package Size *6.1/2x3" *18"x 3.1/4" Spindle Speed R. P. M. 3600 - 4000 5000 - 6500 Feed Sliver wt. , 120 lbs/144 lbs 172-240 lbs. Yarn Range 4.1/4" pitch Frames 6 -10 Ips 3 -10 lbs 4.3/4 pitch Frames 7-16 lbs. 3-14 lbs 5.1/2 pitch Frames 20-40 lbs 8-20 lbs. Drafting Single Zone Two Zone If other indirect savings such as floor space, lighting, furnishings, improvement in winding, weaving etc. are considered the pay-back period is further reduced. The pay-back will be more attractive if based on extra production retaining all the existing M/cs WE CLAIM: 1. A ring spinning frame having double drafting zones comprising: a first top conductor (Tl) for feeding sliver from a sliver can; a primary zone retaining roller (Rl) and a primary zone retaining pressing roller (PI) receiving sliver from said top conductor; a lattice gill primary drafting zone (Dl) over which the sliver from the primary zone retaining and pressing rollers is drawn by a primary zone delivery roller (D2) and a delivery pressing roller (DP); a second top conductor (T2) downstream of the delivery and pressing rollers (DL, DP) receiving the sliver therefrom; a retaining roller (R2) and a retaining pressing roller (P2) through which the sliver from the second top conductor passes; a secondary apron tumbler roller drafting zone (D2) downstream of said retaining and pressing rollers (R2, P2) on which said sliver passes; and a drawing roller (DR) and a drawing pressing roller (DP) for drawing the sliver from the secondary drafting zone over a stop motion feeler (SM) onto a spindle (P) mounted on a flyer (FR) and driven by a cylinder (CY), a bobbin or pirm for winding the yarn being mounted on the spindle. 2. Ring spinning frame substantially as herein described, particularly with reference to the accompanying drawings. A ring spinning frame having double drafting zones comprising: a first top conductor (Tl) for feeding sliver to a pair of primary zone retaining and pressing rollers ( R1,PI ); a lattice gill primary drafting zone (Dl) through which the sliver is drawn by a pair of delivery and pressing rollers ( DL, DP) to a second top conductor (T2) from which the sliver is passed to a secondary apron tumbler roller drafting zone (D2) by a pair of retaining and pressing rollers (R2, P2), and a pair of drawing and pressing rollers ( DR, DP) for drawing the sliver from the secondary drafting zone over a stop motion feeler (SM) onto a spindle (P).

Documents:

02431-cal-1997-abstract.pdf

02431-cal-1997-claims.pdf

02431-cal-1997-correspondence.pdf

02431-cal-1997-description (complete).pdf

02431-cal-1997-drawings.pdf

02431-cal-1997-form 1.pdf

02431-cal-1997-form 2.pdf

02431-cal-1997-form 3.pdf

02431-cal-1997-gpa.pdf

02431-cal-1997-letter patent.pdf

02431-cal-1997-reply f.e.r.pdf