Search

CN-118814324-B - Method for realizing automatic piecing of rotor spinning based on regulation and control of tail yarn tail-retaining length

CN118814324BCN 118814324 BCN118814324 BCN 118814324BCN-118814324-B

Abstract

The invention designs an automatic joint method for rotor spinning based on regulating tail yarn tail-retaining length, which aims at temporary stop or power-off stop in the rotor spinning process to cause yarn breakage, uses a standby power supply to supply power, controls the action of each part of a rotor spinning machine, guides and controls mechanisms such as a yarn guiding roller, a winding roller and the like to stop orderly by accurately calculating the length of a spinnable yarn after residual fibers pass through a rotor, ensures that the tail end of the broken yarn is stopped in a yarn guiding tube of a yarn blocking device to finish the automatic tail-retaining function, and then controls a doffing mechanism to unwind the broken yarn into a rotor coagulation groove as seed yarn when restarting or equipment is powered on, and mutually overlaps and twists fiber flows formed in the rotor coagulation groove by cotton sliver fed by the cotton feeding roller through a carding roller and a fiber conveying channel to finish joint actions, and further regulates and controls parameters such as linear density, twist, strength and the like of the seed yarn-fiber flow twisting body, improves the joint success rate, completes the automatic joint function with high quality, and improves the production efficiency of enterprises.

Inventors

  • CHEN YOURONG
  • WANG LINGJUN
  • XUE YUAN
  • LI JINJIAN

Assignees

  • 浙江泰坦股份有限公司

Dates

Publication Date
20260505
Application Date
20240827

Claims (9)

  1. 1. A method for realizing automatic joint of rotor spinning based on regulating tail yarn tail-retaining length is characterized in that aiming at a rotor spinning machine with a standby power supply, the tail yarn tail-retaining position of a power-off stop machine is regulated and controlled, and the stop tail-retaining method is implemented as follows in steps A to B; Step A, naturally stopping the carding roller and the rotating cup according to own inertia, controlling the speed reduction operation of the cotton feeding roller, the yarn guiding roller and the winding roller based on a standby power supply and a PLC (programmable logic controller), reducing the speed of the cotton feeding roller, the yarn guiding roller and the winding roller to 30% -60% of the working speed in the same ratio, and then entering the step B; Step B, the PLC sends a command for stopping feeding cotton to the cotton feeding roller, controls the cotton feeding roller to instantaneously reverse and stop, breaks cotton slivers conveyed by the cotton feeding roller at the distance point position of the carding roller, and converts fibers remained in the carding roller, the fiber conveying channel and the rotating cup into yarns under the action of the carding roller, the fiber conveying channel, the rotating cup, the yarn guiding roller and the winding roller under the action of the carding roller, the fiber conveying channel, the rotating cup, and simultaneously controls the yarn guiding roller and the winding roller to wind yarns on a winding mechanism, stops the tail ends of the yarns in a yarn guiding and twisting blocking pipe, and controls the yarn guiding roller and the winding roller to stop; In the step B of the shutdown tail-retaining method, the fibers remained in the carding roller, the fiber conveying channel and the rotating cup comprise cotton sliver fibers which are converted by the carding roller when the cotton feeding roller instantaneously rotates reversely, residual fibers in the carding roller, residual fibers in the fiber conveying channel, residual fibers on a sliding surface in the rotating cup and residual fiber rings in a coagulation groove in the rotating cup, and the fibers are converted into corresponding lengths of yarns under the action of the carding roller, the fiber conveying channel, the rotating cup, the yarn guiding roller and the winding roller Obtained as follows, then according to the length of the converted yarn The following formula is performed: (23); For the tail length Means that the yarn feeding roller stops feeding cotton, and the yarn feeding roller starts to draw yarn at the linear speed after the yarn feeding roller is powered off Run for a specific time Stopping the drawn yarn length, and determining the length of the drawn tail after controlling the drawing roller and the winding roller The yarn is wound on a winding mechanism, the tail end of the yarn is stopped in a yarn guiding and twisting resisting pipe, and finally the yarn guiding roller and a winding roller are controlled to stop rotating, Representing the corresponding tail length of the yarn-guiding roller The length of time the yarn is running, The linear speed of the yarn drawing roller after power failure is shown, The length of the bottom of the yarn-guiding twist-retarding tube from the stripping point in the rotary cup is shown, Representing the length of the yarn-guiding twist-blocking tube; firstly, according to the weight of cotton sliver fiber transferred by a carding roller during instantaneous inversion of a cotton feeding roller Weight of residual fibers in carding roll Weight of residual fibers in fiber transfer channels Weight of residual fibre on slip plane in rotor Weight of residual annulus fibrosus in a coagulation tank in a rotor Sum of the weights of (2) Pressing down Obtaining the total residual fiber weight Corresponding to the number of the weight of the fiber ring in the coagulation groove of the rotating cup And the weight of residual fibers of less than one complete annulus ; Then aiming at the residual fiber, gradually superposing the residual fiber in a coagulating tank in a rotating cup according to the combining effect of the rotating cup to form a thick-to-thin fiber ring Obtaining the length corresponding to the yarn tail , wherein, Represents the linear density of the yarn; Finally according to Obtain the length of , wherein, Indicating the diameter of the coagulation groove in the rotor, Representing the length of the yarn corresponding to all the residual fibers; C to E, regulating and controlling the lap joint process of the new fiber loop and the tail yarn after restarting spinning based on electrifying, and executing the joint method as follows; step C, controlling the rotating cup and the carding roller to start working, controlling the winding roller to rotate reversely, storing the unwinding yarn in the yarn storage tube under the action of negative pressure air flow as seed yarn, controlling the winding roller to stop, and entering the step D; Step D, controlling a cotton feeding roller to start feeding cotton sliver, separating the cotton sliver into fibers through a carding roller and a fiber conveying channel, conveying the fibers into a coagulation tank in a rotary cup to be coagulated to form a fiber flow, and then entering the step E; And E, controlling the yarn drawing roller to reversely rotate, releasing seed yarns in the yarn storage tube to sink into a coagulation groove in the rotary cup under the action of negative pressure air flow, overlapping with fiber flow in the coagulation groove, twisting and wrapping each other to realize a joint, continuing rotary cup spinning to generate yarns, and then controlling the yarn drawing roller and a winding roller to positively rotate, and continuously outputting and winding the generated yarns into bobbin yarns.
  2. 2. The method for realizing automatic piecing in rotor spinning based on regulating the tail length of tail yarn according to claim 1, wherein the weight of sliver fiber transferred away by the carding roller at the instant reverse rotation of the cotton feeding roller is as follows Obtained as follows: According to the length of the held fiber between the holding point of the cotton feeding roller and the gauge point of the carding roller Pressing down Obtaining the weight of the held fiber , wherein, Indicating the fixed weight of cotton sliver fed by a cotton feeding roller; Then the transfer rate of the fiber is transferred to the carding roller according to the instantaneous reverse rotation of the cotton feeding roller Pressing down Weight is obtained 。
  3. 3. The method for realizing automatic piecing of rotor spinning based on regulating and controlling tail length of tail yarn according to claim 1, wherein the weight of residual fiber in the carding roll Obtained as follows: Pressing the button Obtaining the rotating arc length of the carding roller Corresponding time , wherein, The length of the carding roller arc corresponding to the distance point of the carding roller to the fiber conveying channel is expressed, The rotating speed of the carding roller is shown, Indicating the diameter of the carding roller; Then press down Weight is obtained , wherein, The linear speed of the yarn drawing roller after power failure is shown, Representing the linear density of the yarn.
  4. 4. The method for realizing automatic piecing in rotor spinning based on regulating tail yarn retention length according to claim 1, wherein the weight of residual fiber in the fiber conveying channel Obtained as follows: First press Obtaining the linear velocity at the inlet of the fiber conveying channel , wherein, A correction factor indicating the conversion of the opening roller linear velocity into the fiber transfer velocity, The rotating speed of the carding roller is shown, The diameter of the carding roller is shown, The linear speed of the carding roller is shown; Simultaneously pressing Obtaining the linear velocity at the outlet of the fiber conveying channel , wherein, A correction factor representing the transfer speed of the fiber from the linear speed of the rotor, The rotating speed of the rotating cup is indicated, Representing the diameter of the corresponding circumference on the sliding surface of the rotor; Then press down Obtaining the transfer time of the fiber flow in the fiber conveying channel , Representing the length of the fiber transport channel; finally press Weight is obtained , wherein, The linear speed of the yarn drawing roller after power failure is shown, Representing the linear density of the yarn.
  5. 5. The method for realizing automatic piecing of rotor spinning based on regulating tail yarn remaining length as claimed in claim 1, wherein the weight of residual fiber on slip plane in the rotor Obtained as follows: first according to transfer of fibres to rotor the radius of the corresponding rotating cup at a certain point of the surface is At an angular velocity of And using the fiber at the point as a fiber dot to obtain a centrifugal force applied to the fiber dot as Component force of fiber dots along the wall of the rotor cup to the direction of the coagulation groove Component force of fiber dots perpendicular to the wall of the rotor cup Acceleration of fiber spots along slip plane of rotor Mass of fiber mass Coefficient of friction between the fibres and the wall of the rotor Inclination angle of inner wall of rotary cup The kinetic equation was constructed as follows: (11); the time for the fiber to slip from the outlet of the fiber transport channel to the coagulation tank in the rotor is then defined as According to the fiber edge rotation in the period the length of the bus sliding of the sliding surface of the cup is Accelerating in the formula (11) The derivation is obtained as follows: (12); then according to the whole sliding process of transferring the fiber from the outlet of the fiber conveying channel to the coagulating tank of the rotary cup, the fiber in the formula (12) And (3) with In a linear increasing relationship, the following is constructed: (13); Wherein, the Expressed as the distance of the outlet position of the fiber conveying channel from the position of the coagulation groove in the rotor along the generatrix of the rotor, Expressed as the coagulation groove diameter; And then the formulas (11), (12) and (13) are combined, when the fiber slides from the outlet of the fiber conveying channel to the coagulation groove in the rotating cup, namely Then, by the feature root method, the following formula (14) is adopted: (14); obtaining the time for the fiber to slide from the outlet of the fiber conveying channel to the coagulation groove in the rotary cup ; Finally press Weight is obtained , wherein, The linear speed of the yarn drawing roller after power failure is shown.
  6. 6. The method for realizing automatic piecing of rotor spinning based on regulating tail yarn remaining length as claimed in claim 1, wherein the weight of residual fiber ring in the coagulation tank in the rotor Pressing down Weight is obtained , wherein, The linear density of the yarn is indicated, Indicating the diameter of the coagulation groove in the rotor.
  7. 7. The method for realizing automatic piecing of rotor spinning based on tail length regulation of tail yarn according to claim 1, wherein in step E of the piecing method, the yarn guiding roller is controlled to rotate reversely, seed yarn in the yarn storage tube is released to sink into a coagulation groove in a rotor under the action of negative pressure air flow, so that the seed yarn is overlapped with fiber flow in the coagulation groove, the upper limit of the overlapped length is the circumference of the coagulation groove of the rotor, and in the overlapped state, the fiber flow coagulated in the coagulation groove of the rotor forms fiber rings.
  8. 8. The method for realizing automatic piecing of rotor spinning based on regulating tail yarn retention length according to claim 7, wherein each control parameter is regulated and controlled as follows before the piecing steps C to E are executed: at speed for winding rollers Inversion time The length of the yarn unwound from the winding mechanism is The yarn of (2) is stored in a yarn storage tube to be used as seed yarn under the action of negative pressure air flow, and the following model is constructed: (24); Wherein, the Indicating the length of the seed yarn in the yarn storage tube released by controlling the inversion of the yarn guiding roller in the step E, 、 Respectively represent In comparison with the prior art A preset lower limit length and a preset upper limit length of the floating; based on the control of the yarn-guiding roller in the definition step E to take the speed as Reverse release delay Construction of the overlap length of the seed yarn in the yarn storage tube and the fiber flow in the coagulation tank And the length of the seed yarn in the yarn storage tube released by reversing the yarn guiding roller The relationship is as follows: (25); Wherein, the The length of the bottom of the yarn-guiding twist-retarding tube from the stripping point in the rotary cup is shown, Indicating the length of the yarn-guiding twist-resisting tube and releasing delay Means the time length from starting to releasing seed yarn reversely to stopping from the yarn pulling-out; According to the linear density of the yarn Coefficient of twist Critical twist And according to the rotational speed of the rotor Line speed of yarn-drawing roller after power-off Initial twist Further according to the overlapping length Delay of twisting Twist of the joint is According to the instantaneous twist theory of the yarn arm in the rotor, the following construction is carried out: (26); I.e. twist delay Is regulated by the twist coefficient And critical twist For reference, by controlling the overlap length Realized by twisting time delay The twisting time after the seed yarn and the fiber ring are overlapped to form a twisting body, namely the time from the yarn guiding roller to stop releasing the seed yarn to the yarn guiding starting of the winding mechanism; According to the method of stopping machine and keeping tail, controlling the lead-out length of the yarn guiding roller and the winding roller The yarn of (2) is wound on a winding mechanism as a tail-retaining length, the stop position of the tail end of the yarn in the yarn guiding and twisting resisting pipe is determined, and the overlapping length is combined According to formula (25), determining the length of the seed yarn in the yarn storage tube released by reversing the pair of yarn-drawing rollers Further according to formula (24), the length of yarn unwound from the winding mechanism is worked on the winding roller Regulated and controlled according to the overlapping length Is regulated and controlled by a formula (26) to realize twisting time delay And further determining the control parameters in the steps C to E of the joint method.
  9. 9. The method for realizing automatic piecing of rotor spinning based on regulating tail length of tail yarn according to claim 8, wherein in the execution of the piecing method steps C to E, further comprising a method for regulating the morphology and structure of piecing based on the distribution of the linear density of piecing, the following steps F to G are included: Step F, firstly, carrying out joint linear density distribution analysis as follows: According to the joint position, the yarn guiding is finished when the cotton sliver is fed from the cotton feeding roller to the winding mechanism, and the yarn guiding is overlapped on the fiber ring of the revolving cup coagulation groove, and the release time delay is realized The seed yarn which enters the rotary cup coagulation tank is formed by three parts of newly fed fiber flow in the rotary cup coagulation tank when yarn guiding is started; wherein, regarding the weight of the fiber ring, the sinking yarn delay is included according to the start of yarn guiding from the cotton feeding roller to the winding mechanism Delay of release Twist delay Three time periods; Time delay for sinking yarn Means the time length from the cotton sliver feeding of the cotton feeding roller to the start of the drawing of the yarn drawing roller to release the seed yarn reversely; According to the speed of feeding cotton sliver to the cotton feeding roller Weight of cotton sliver The weight of the annulus is obtained as follows ; (27); With respect to release delay The weight of the seed yarn which enters the coagulation groove of the rotary cup correspondingly comprises the length of the seed yarn according to all residual fibers Is formed into yarn and has length of According to the weight of the residual fiber corresponding to the yarn tail Linear density of yarn Combined with overlap length The method comprises the following steps: (28); obtaining release delay Weight of seed yarn entering coagulation tank of rotary cup ; Regarding the weight of the newly fed fiber stream in the rotor coagulation tank at the start of yarn feeding, the following formula is adopted according to the combination effect of the fibers in the rotor coagulation tank: (29); Obtaining the weight of the newly fed fiber stream in the coagulation tank of the rotor when starting yarn drawing ; The following formula is followed: (30); obtaining the total weight of the fibers at the joint as ; Step G, regulating and controlling the morphological structure of the joint: According to weight of The fibers are distributed in the form of fiber rings around the rotor coagulation tank, and the weight is as follows according to the combination effect of the fibers in the rotor coagulation tank The distribution of the newly fed fiber stream around the coagulation tank is linear, the linear density of the fiber ring is Maximum linear density and bond length of the newly fed fiber stream The maximum linear density of the yarn tail and the maximum linear density of the seed yarn in the coagulation groove of the rotor are all set as the linear density of the yarn Taking the stripping point in the rotary cup as a reference, in the perimeter of one coagulation groove, the morphological structure at the joint from left to right is changed into a rough joint 1, a detail and a rough joint 2, and the linear densities of the rough joint 1, the detail and the rough joint 2 are respectively 、 、 The construction is as follows: (31); According to the overlapping length According to formula (26), by controlling the twist delay Realizing the twist of the joint Is controlled by combining sand setting delay Delay time of release And controlling the maximum and minimum linear density of the joint to realize the regulation and control of the joint morphological structure.

Description

Method for realizing automatic piecing of rotor spinning based on regulation and control of tail yarn tail-retaining length Technical Field The invention relates to a method for realizing automatic piecing of rotor spinning based on regulation of tail yarn tail-retaining length, belonging to the technical field of spinning automation. Background In the rotor spinning process, yarn breakage is caused by temporary stopping or power-off stopping, in order to continue spinning, the following actions are needed to be carried out, ① is needed to clean fibers remained in a spinning device, ② is needed to find out broken ends from a bobbin, a specific yarn length is pulled out to pass through a yarn drawing roller holding point and enter a yarn drawing twisting blocking tube, the yarn is extended to a stripping point in a rotor under the action of negative pressure air flow, ③ is used for feeding cotton sliver to a cotton roller, a single fiber flow separated by combing is sent into the rotor through a combing roller and an air flow channel to be condensed into new fiber strands, the new fiber strands are converged with seed yarns positioned at the stripping point in the rotor and wrapped to complete a joint, and ④ is used for starting a winding mechanism to carry out normal spinning. The joint mode includes manual joint, semi-automatic joint and full-automatic joint. Aiming at temporary stop and outage stop, the technical proposal has the following problems that the yarn tail after ① yarn breakage is wound on bobbin yarn, the yarn needs to be re-spliced for continuous spinning, and how to regulate a winding mechanism after ② yarn breakage, so that the yarn tail stays in a yarn guiding and twisting resisting pipe, the tail-leaving length of tail yarn also needs to be designed, and the tail-leaving yarn and newly-condensed fiber strands can be overlapped and intersected at a rotor stripping point to form a splice, thereby the prior art has low application efficiency. Disclosure of Invention The invention aims to solve the technical problem of providing a method for realizing automatic joint of rotor spinning based on regulating and controlling tail-retaining length of tail yarn, adopting a brand new design to effectively realize the designed shutdown tail-retaining method and joint method, effectively solving the shutdown yarn breakage problem in the rotor spinning process and improving the joint working efficiency. The invention adopts the following technical scheme for solving the technical problems: 1. In order to avoid the need of finding out broken ends from cheeses to carry out the head-producing action again in the traditional piecing process, the invention uses the UPS power supply after the power failure to control the orderly stopping of all parts of the rotor spinning machine, so that the broken ends and the tails are reserved in the yarn-guiding tube of the twister to finish the tail yarn reserving function, and the broken ends and the tails are used as the tails to lay the foundation for automatic piecing when restarting. 2. In order to accurately control the tail yarn stay position, the weight of the fiber remained in the spinning device after power failure and the length of the spinnable yarn are calculated aiming at different rotor spinning equipment, different spinning raw materials and processes, and the position of the tail yarn stay in the yarn guiding and twisting resisting pipe is accurately controlled by the design of the tail yarn stay length. 3. The invention relates to a method for regulating and controlling the release length of seed yarn based on the change of yarn storage length, which is characterized in that the yarn length stored in a yarn storage tube under the action of negative pressure is regulated and controlled by controlling the reversing speed and time of a winding roller, and the length range of the yarn in the yarn storage tube, which is used as seed yarn to be released by a yarn guiding roller when a joint starts, is further regulated and controlled. 4. The invention discloses a method for realizing automatic joint of seed yarn and fiber flow in a rotor, which is characterized in that the overlapping length and twisting time of the seed yarn and the fiber flow are regulated and controlled through the cooperative change of the starting time of a cotton feeding roller, the releasing length and time of the seed yarn and the winding time of a winding drum, the morphological structure and mechanical property of a seed yarn-fiber flow twisting body are further regulated and controlled, and the quality and quality of the joint are improved. Compared with the prior art, the method for realizing automatic joint of rotor spinning based on regulating and controlling the tail-retaining length of the tail yarn has the following technical effects: The invention designs an automatic piecing method for rotor spinning based on regulating tail yarn tail-retaining length, which aims at provid