Title of Invention

"A DRAW FRAME FOR BLENDING SLIVERS OF DIFFERENT COLOUR/FIBER MATERIAL"

Abstract

A draw frame for blending slivers of different colour/fiber material where the composition of the Abstract . product can be changed in real time so as to produce a regular effect in the product according to a desired programmed pattern. Further, the selection or rejection of individual colour fiber, in order to control different colour components in varying proportion to get random or pattern distribution of single fibre component in the two dimensions of the strand cross-section, as well as a random or pattern distrubution of fibres along its length can be controlled.

Full Text

This invention relates to a draw frame for blending slivers of different colour/fibre material. Several computerized blending systems featuring electronic weighing, computer controlled compensation, programmable electronic bale openers which automatically open and mix the fibres from different bales have been suggested in the art. The blend control monitor provides complete monitoring and control of the blend line. The bale-digestor produces colour blends by supplying the bale components to the weight hoppers with timing controlled by the microprocessor. However, in none of the systems described above, the composition of the product can be changed in real-time so as to produce a regular effect in the product according to a desired programmed pattern. Further, the present draw frames cannot select or reject individual colour fibres in order to control different colour components in varying proportion to get random or pattern distribution of single fibre component in the two dimensions of the strand cross-section, as well as a random or pattern distribution of fibres along its length. An object of this invention is to propose a novel construction of a draw frame capable of blending slivers of different colours or fibre materials longitudinally in a controlled manner. Another object of this invention is to propose a draw frame which produces a regular or random colour pattern in the output sliver by changing the colour/fibre composition in real-time by blending slivers of different colours/fibres in a controlled manner longitudinally in the output sliver. Still another object of this invention is to propose a draw frame which produces different colour pattern in warp and weft yern to produce desired fabric. Yet another object of third invention is to propose a draw frame which produces complicated colour patterns in fabrics. A further object of this invention is to propose a draw frame which produces shadding effect in warp and weft direction in fabric which is not possible to produce on fabric dyeing machines. According to this invention there is provided a draw frame for blending slivers of different colour/fibre material characterized in that the draw frame comprising:- (a) a pre-draw zone (A) consisting of two predrafting sections comprising four pair of known rollers (R4A, R5A, R4B, R5B) with one pair of rollers placed over the other pairs of rollers, the two pairs of rollers (R4a, R5A) forming upper set of rollers for pre-drafting sliver of colourA/fibre material 'A' and the two pairs of rollers (R4B, R5B) forming lower set of rollers forpre-drafting sliver of second colours 'B'/fihre material 'B'; (b) a convergence zone (C) between the said two pre-drafting sections where the predrafted slivers of colour A/fibre material A from the said upper set of rollers and the pre-drafted slivers of colour B/fibre material B from the lower set of rollers converge together into,the main-drafting, section B herein described; (c) a main drafting section B wherein the different pre-drafted slivers are fed together,the said-main drafting_section having-three pair of Rollers RI, R2, RS wherein the said rollers R2, R3 and R4B receive the drive transmitted from Roller's (R4A) through a set of gears; (d) four motors (M1, M2, M3, M4) wherein motor (M2) drives the roller (R4A), motor (M3) drives rollers (R5A) and motor (M4) drives Toilers (R5B), motor (M1) driving the said rollers (R1), the speed of said motors being individually controlled by controllers (CO1, CO2, CO3, CO4) having a dc-dc chopper power circuit, the said controllers receiving signal from a micro-computer (MC) which is connected to a personal computer (PC) as a background processor to the said micro-computer, the said chopper' circuit in series with a free- wheeling- diode (D1), a motor (M) having fixed excitation field winding, resistance (R12) connected to the base of transister (Q1), an Opti-isolator (OP) providing physical isolation between the said chopper circuit and an interface circuit, wherein the said chopper circuit, comprises of a second- transistor (Q2) having a snubber circuit consisting of capacitor (C6) in series with a resistor (R14) and a Diode (D2) across the said resistor (R14), the said second transistor (Q2) having a discharging resistor (R13), wherein the said interface circuit comprises a digital to analogue converter (DAC) which is adapted-to convert, signal from the said micro-computers (MC) to an analog signal 'A' applied to a comparator (CT), the reference signal to the said comparator being fed from a function generator (FG), and the output of said comparator being applied to said Opti-isolator (OP). In accordance with this invention the predrafting zone comprises a first set of rollers for a first predrafted sliver and a second set of rollers for a second predrafted sliver. The first set of rollers comprises the upper set of rollers, the second set of rollers constituting the lower set of rollers and, such that the first and second slivers frame the upper and lower set of rollers converge to the convergence zone. The first or upper set of rollers comprises a first and second pair of rollers disposed in a spaced relationship to each other, a third motor for driving said first pair of rollers, a second motor for driving said second pair of rollers. The second or lower set of rollers comprise a first pair and a second pair of rollers disposed in a spaced relationship to each other, a fourth motor for driving said first pair of rollers, said second pair of rollers being driven by said second pair of rollers of the first or upper set of rollers. A control circuit is connected to each of the motors for controlling the speed of said motors, depending on the blend of first and second slivers required in the drawn sliver. Still further, the drawn sliver can have different lengths of different blends by controlling the drive of said motors. The drive means further comprise a first motor for driving a first pair of draw rolls, the second and third pair of draw rolls being driven by said second motor through the second pair of rollers of the first or upper set of rollers of the predraw zone. Further objects and advantages of this invention will be more apparent from the insuing description when read in very conjunction with the accompanying drawings and wherein. Fig. 1. shows the machine of the present invention; Fig. 2. shows a grapple of the length of sliver and speed of the rollers in the predrafting zone; Fig. 3. shows the chopper circuit used in the controller circuit; and Fig. 4. shows the interface circuit. The draw frame along with its drive and electrical circuit is illustrated in the Fig. 1. The draw frame consists of pre-drafting section A formed by the rollers R4A, R4B and R5B and the main-drafting section-B formed by the pair of rollers Rl, R2 and R3. Rollers R4A and R5A form the upper of first set of rollers in the pre-drafting zone A and rollers R4B and R50 form lower and second set of rollers in pre-drafting zone A. Thus the first set of rollers comprise a first pair of rollers R5A and a second pair of rollers R4A. The second set of rollers comprise a first pair of rollers R5B and a second pair of rollers R4B. Between these two drafting sections is a convergence zone C where the predrafted slivers of color A of the upper set of rollers and of color B of the lower set of rollers converge together into the main-drafting section B. The rollers are driven by a multimotor drive system to meet the variable draft requirement of the drawframe. The roller R5A are driven by a third motor M3 and rollers R5B driven by a fourth motor M4. The rollers R4A are driven by a second motor M2. From rollers R4A, the drive is transmitted to rollers R3, R2 and R4B through a set of gears (not shown). The roller Rl is driven by a first motor Ml. Motors Ml, M2, M3 and M4 are dc mo tors,which are individually controlled by a control circuit having a controller co with a dc-dc chopper power circuit. The speed of motor Ml to M4 is controlled by controller coi to CO4 respectively which receive signal from a micro computer MC. The micro-computer MC provides the actuating signal to the drive motor by processing the speed feedback signal and the reference command obtained from a personal computer pc connected as a background processor to the micro-computer Thus, different slivers are predrafted separately in the pre-drafting zone A and then are fed together into the main-drafting section B. There is no draft in the convergence zone C. The ratio of any colour in the blend can be controlled by changing the predraft in a controlled manner such that the linear density of the output sliver remains constant. The complementary speed requirement of the rollers R5A and R5B can be illustrated by the Fig. 2 below, which shows the speed profiles of the motors M3 and M4 connected to the rollers R5A and R5B respectively. Fig. 2 shows the speed profiles of the motors Ms and M4 vs. the length of the output sliver. The center line corresponds to the speed when the two predrafts DA and DB are equal to the mean pre-draft Do. During the Length Li, both motors are running at the same speed and the two colours A & B have equal ratio in the output sliver. Then, simultaneously the speed of motor M3 is increased and that of motor M4 is decreased. As a result color A starts dominating in the product in length Ls. The opposite happens during length L5 and colour B dominates. Length L2 and L4 correspond to the transition periods when the output sliver has intermediate ratios of the two colours. The speeds of the motors Ml and M2, driving the front and second rollers Rl and R2 respectively. Each of the controller circuits CO1 to CO has a chopper circuit of Fig. 3 and an interface circuit of Fig.4. The chopper circuit of Fig. 3 comprises a motor M having a free wheeling diode D1 across it, Motor M has a fixed excitation field winding (not shown), the average voltage across motor M is controlled to regulate the speed of motor M. Thus, for higher speeds we require higher voltages. Resistance R12 is connected to the base of transistor Q1, current being applied to resistor Ri2 from an optisolator OP, such an optisolator OP is required as chopper circuit of Fig.3 operates at 220V and carries 5 amps, whereas, the interface circuit of Fig. 4 operates at a low voltage at 5V and carries a current in the value of milliamps. Thus, optisolator OP provides a physical isolation between the chopper circuit of Fig. 3 and the interface of Fig. 4. The chopper circuit of Fig. 3 further comprises a second transistor Q2 having a snubber circuit consisting of a capacitor C6 in series with a resistor R14, and a diode D2 across said resistor. Transistor has a discharging resistor R13. When no input current is present at resistor R12, the voltage across motor M is low or 0. When a high pulse is given to provide a sufficient base current to transistor Q1, the voltage across transistor Q2 reduces to saturation voltage. Thus, from a high initial voltage across transistor Q2, it goes down to saturation voltage, which is low so that the entire voltage appears across motor M. The signal to the chopper circuit of Fig. 3 is derived from the interface circuit of Fig. 4. The interface circuit comprises a digital analogue converter DAC, which converts a digital signal from the micro computer MC to an analog signal A applied to a comparator CT. The reference signal to comparator CT is fed from a function generator FG. The output of comparator CT is applied to optoisolator OP., WE CLAIM: 1. A draw frame for blending slivers of different colour/fibre material characterized in that the draw frame comprising:- (a) a pre-draw zone (A) consisting of two predrafting sections comprising four pair of known rollers (R4A, R5A, R4B, R5B) with one pair of rollers, placed over the other pairs of rollers, the two pairs of rollers (R4A, RSA) forming upper set of rollers for pre-drafting sliver of colourA/fibre material 'A' and the two pairs of rollers (R4B, R5B) forming lower set of roller for pre-drafting sliver oflsecond-Golours 'B'/fibre material 'B';_ (b) a convergence zone (C) between the said two pre-drafting sections where the predrafted slivers of colour A/fibre material A from the said upper set of rollers and the pre-drafted slivers of colour B/fibre material B from the lower set. of rollers, converge together into the mainrdrafting section B herein described; (c) a main drafting section B wherein the different pre-drafted slivers are fed together the said, maia drafting, section having three pair of Rollers R1, R2, R3 wherein the said rollers R2, R3 and R4B receive the drive transmitted from Roller's (R4A) through a set of gears; (d) four motors (M1, M2, M3, M4) wherein motor (M2) drives the roller (R4a), motor (M3). drives-rollers (R5A) and motor (M4). drives rollers (RSB), motor (M1) driving the said rollers (R1), the speed of said motors being individually controlled by controllers (CO1, CO2, CO3, CO4) having a dc-dc chopper power circuit, the said controllers receiving signal from a micro-computer (MC) which is connected to a personal computer (PC) as a background processor to the said micro-computer, the said chopper circuit in series with a free wheeling diode (D1), a motor (M) having fixed excitation field winding, resistance (R12) connected to the base of transistor (Q1), an Opti-isolator (OP) providing physical isolation between the said chopper circuit and an interface circuit, wherein the said chopper circuit comprises of a second transistor (Q2) having a snubber circuit consisting of capacitor (C6) in series with a resistor (R14) and a Diode (D2) across the said resistor (R14), the said second transistor (Q2) having a discharging resistor (R13), wherein the said interface circuit comprises a digital to analogue converter (DAC) which is adapted to convert signal from the said micro-computers (MC) to an analog signal 'A' applied to a comparator (CT), the reference signal to the said comparator being fed from a function generator (FG), and the output of said comparator being applied to said Opti-isolator (OP). 2. A draw frame for blending slivers of different colour/fibre material as substantially herein described and illustrated with reference to accompanying drawings.

Documents:

535-del-1995-abstract.pdf

535-del-1995-claims.pdf

535-del-1995-correspondence-others.pdf

535-del-1995-correspondence-po.pdf

535-del-1995-description (complete).pdf

535-del-1995-drawings.pdf

535-del-1995-form-1.pdf

535-del-1995-form-2.pdf

535-DEL-1995-Form-3.pdf

535-del-1995-form-4.pdf

535-del-1995-gpa.pdf

535-del-1995-petition-138.pdf