A method for preparing ring-spun fancy yarn

Abstract

The present invention belongs to the field of textile processing technology, and relates to a method for preparing a ring-spun fancy yarn, wherein two or more rovings are spun together by a ring spinning frame, and the ring spinning frame comprises an intermittent feeding rear roller, a middle roller, and a front roller, wherein at least one roving is intermittently fed by the intermittent feeding rear roller. In the process of preparing the ring-spun fancy yarn, the present invention feeds the head end of the fiber whisker into the range controlled by the friction force boundary of the middle roller, and adjusts the distance between the head end and the jaws of the middle roller, thereby effectively solving the detail problem generated in the transition section when two rovings are alternately fed or one roving is intermittently fed in the prior art, avoiding the empty distance caused by the rear roller stopping rotating, thereby improving the quality and appearance quality of the ring-spun fancy yarn.

Description

Technical Field

[0001] The invention belongs to the technical field of textile processing and relates to a method for preparing ring-spun fancy yarn. Background Art

[0002] Ring spinning is the most mature and widely used spinning technology. In addition to spinning ordinary yarn counts, it can also spin fancy yarns such as slub yarn, segment color yarn, segment color slub yarn, etc. When two or more rovings are used to spin fancy yarns, there are usually two options. Option 1: One roving is directly fed by the middle roller of the spinning frame and is only drafted in the front drafting zone; the other roving is fed by the rear roller, first drafted in the rear drafting zone, and then enters the front drafting zone. Option 2: The rear roller of the spinning frame is transformed into a multi-channel feeding system, and the two rovings are fed into the system through different rear rollers, and yarns are formed after being drafted in the rear drafting zone and the front drafting zone.

[0003] However, no matter which scheme is adopted, when two rovings are fed alternately or one roving is fed intermittently, the fancy yarn spun will have detail problems in the transition section where the rovings are fed alternately, which seriously affects the quality of the fancy yarn. The reason is that according to the roller drafting principle, when the fiber is drafted between two pairs of rollers, the center distance of the two pairs of rollers must be greater than the main length of the spun fiber. Therefore, during the drafting process, in addition to the fibers controlled by the middle roller and the rear roller, there are also floating fibers that are not controlled by the two rollers. These floating fibers are divided into slow floating fibers controlled by the friction force boundary of the rear roller and fast floating fibers controlled by the friction force boundary of the middle roller. The entire drafting process is the process of accelerating the slow floating fibers into fast floating fibers.

[0004] Since the friction force boundaries of the middle roller and the back roller are distributed within a certain range, when two rovings are fed alternately or the roving fed by the back roller stops feeding, the back roller will stop rotating, while the middle roller continues to rotate forward. At this time, in the drafting area between the back roller and the middle roller, the fast floating fibers controlled by the friction force boundary of the middle roller will continue to move toward the middle roller jaws and be transferred to the front drafting area. Therefore, when the back roller stops rotating, the slow floating fibers originally controlled by the friction force boundary of the back roller will lose this control force, while the fast floating fibers controlled by the friction force boundary of the middle roller will continue to move toward the middle roller jaws. Since the back roller has stopped rotating, a distance originally occupied by the back roller will be vacated in the drafting area between it and the middle roller. This vacated distance means that when the roving is fed to the back roller again, it will take some time for the fibers to pass through this vacated distance again and reach the middle roller jaws. This can result in the spun fancy yarn having fine details or a longer transition section at the transition between the two rovings, because during this time the yarn diameter or fiber distribution may change, which affects the quality and appearance of the yarn.

[0005] When spinning fancy ring-spun yarns such as slub yarn and segment-colored yarn, the usual method is: one roving (roving I) is used as the base yarn and is directly fed by the middle roller of the spinning frame; the other roving (roving II) is used as other components or colors and is fed by the back roller of the spinning frame. Due to the characteristics of the drafting device of the ring spinning frame, roving I will be fed continuously, while roving II can be fed continuously or intermittently. The purpose of spinning slub yarn or segment-colored yarn can be achieved by adjusting the speed changes of the middle roller and the back roller of the spinning frame. When roving II is fed intermittently, it can be used to spin fancy yarn varieties such as slub yarn and segment-colored slub yarn. The control method of intermittent feeding of roving II is to operate and stop the back roller of the spinning frame according to the rules set by the control system. However, when the back roller stops running, since the middle roller keeps running, the fiber strands between the back roller and the middle roller (especially the fibers with the head end close to the jaws of the middle roller) will continue to be drafted and transferred under the action of the friction force of the middle roller. Therefore, when the back roller is running again to feed the roving II, it takes some time for the head end fiber to be controlled by the friction force of the middle roller again. This will cause the yarn spun in the transition section to have yarn defects such as fine lines or a long transition section, which seriously affects the appearance quality of the ring-spun fancy yarn. Summary of the invention

[0006] The purpose of the invention is to solve the problems existing in the prior art and provide a method for preparing ring-spun fancy yarn.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A method for preparing a ring-spun fancy yarn comprises spinning two or more rovings together by a ring spinning frame, the ring spinning frame comprising an intermittent feeding rear roller, a middle roller and a front roller, wherein at least one roving is intermittently fed by the intermittent feeding rear roller, and when the roving in a rear drafting zone stops being drafted, the head end of the fiber strand is fed into a range controlled by the friction force boundary of the middle roller, so that the distance between the head end of the fiber strand and the jaws of the middle roller is 2-3 mm.

[0009] As the preferred technical solution:

[0010] According to the method for preparing a ring-spun fancy yarn, the roller moves periodically after intermittent feeding, the start time of a single cycle is recorded as t1, the end time is recorded as t3, and there are four increasing times between t1 and t3, which are recorded as t2, ta, and tb respectively;

[0011] Between t1 and t2, the roller after intermittent feeding rotates forward at a linear speed of v1; between t2 and ta, the roller after intermittent feeding does not rotate; between ta and tb, the roller after intermittent feeding rotates forward at a linear speed of v2; between tb and t3, the roller after intermittent feeding does not rotate;

[0012] Between time t1 and time ta, the roving in the rear drafting zone is subjected to the drafting action; between time ta and time t3, the roving in the rear drafting zone stops being subjected to the drafting action;

[0013] At the time ta, a point on the roving in the rear drafting zone is gripped and moves forward at a speed of v2, and stops moving forward at the time tb, and stops gripping at the time t3; the gripping force is greater than the pressure between the middle roller and the middle top roller; at the time tb, the head end of the fiber strand has entered the range controlled by the friction force boundary of the middle roller, and at this time, the roving in the rear drafting zone needs to be tightly gripped to prevent it from being taken away by the middle roller before the roller rotates again after intermittent feeding, so the present invention does not stop gripping until the time t3, and at the same time controls the gripping force to be greater than the pressure between the middle roller and the middle top roller;

[0014] At time ta, the distance between the gripping point and the intermittent feeding rear roller jaws and the distance between the gripping point and the middle roller jaws are both smaller than the main length of the roving in the rear drafting zone, otherwise it will cause unexpected drafting and cannot be accurately controlled;

[0015] Between t1 and t3, the middle roller rotates forward continuously at a linear speed of v3, and the front roller rotates forward continuously at a linear speed of v4; the interval between t2 and t1, v1, v3, v4, and the distance between the middle roller jaws and the front roller jaws all depend on the spinning process, and are related to process parameters such as spindle speed, spinning count, twist, roving quantity, and rear zone drafting multiple. In ordinary ring spinning, the linear speed of the front roller is generally 15~20m / min, the linear speed of the middle roller is generally 0.2~0.5m / min, and the linear speed of the intermittent feeding rear roller is generally 0.2~0.48m / min.

[0016] In the prior art, between the time t2 and the time t3, the intermittent feeding rear roller never rotates, and does not hold a point on the roving in the rear drafting zone and move forward.

[0017] In the preparation method of a ring-spun fancy yarn as described above, the interval between moment ta and moment t2 is 0.3~0.5s. At moment t2 when the roller stops rotating after intermittent feeding, under the influence of the friction boundary, the head end of the fiber strand will also be affected by the friction boundary of the middle roller. If a point on the coarse yarn in the rear drafting zone is grasped at moment t2 and moved forward at a speed of v2, the number of fibers affected by the friction boundary of the middle roller will increase, which is not conducive to quality control.

[0018] In the method for preparing a ring-spun fancy yarn as described above, the interval between time tb and time ta is 0.1~0.2s, and v2 is 10~20mm / s; the product of the time interval between tb and ta and v2 is equal to the distance between the head end of the fiber strand and the jaws of the middle roller.

[0019] In the method for preparing a ring-spun fancy yarn as described above, the interval between the time t3 and the time tb is 0.1-0.2 s, and the purpose of such setting is to enable the fiber head end to be fully affected by the friction force of the middle roller.

[0020] In the method for preparing a ring-spun fancy yarn as described above, at time ta, the distance between the holding point and the jaws of the intermittent feeding rear roller is 20~40mm, and the distance between the holding point and the jaws of the middle roller is 15~25mm; the main length of the roving in the rear drafting zone is 30~55mm.

[0021] In the method for preparing a ring-spun fancy yarn as described above, other rovings are continuously fed by the middle rollers.

[0022] In the method for preparing a ring-spun fancy yarn as described above, the ring spinning frame also includes a continuous feeding rear roller, and other rovings are continuously fed by the continuous feeding rear roller.

[0023] As described above, the ring spun fancy yarn is a ring spun segment colored yarn or a ring spun bamboo yarn, the average length of the transition section is 3-5 mm, and the number of details of the ring spun segment colored yarn is 1-2 pieces / km. It can be seen that, compared with the prior art, the ring spun fancy yarn spun by the present invention has fewer details and a shorter transition section.

[0024] The present invention also provides a preparation device for ring-spun fancy yarn, comprising a ring spinning frame, the ring spinning frame comprising an intermittent feeding rear roller, a middle roller, and a front roller, the preparation device for ring-spun fancy yarn also comprising an upper roller, a lower roller, a controller, and a lifting mechanism;

[0025] The central axes of the upper roller and the lower roller are parallel to the left and right directions, the upper roller is located above the lower roller, and the upper roller and the lower roller are located between the intermittent feeding rear roller and the middle roller at the same time;

[0026] The controller controls the operation of the intermittent feeding rear roller, middle roller, front roller and bottom roller, and adjusts the height of the upper roller through the lifting mechanism. When the height of the upper roller is the smallest, the distance between the upper roller and the lower roller is 0. At this time, the roving in the rear drafting zone is held. When the height of the upper roller is the largest, the distance between the upper roller and the lower roller is greater than 0.

[0027] As the preferred technical solution:

[0028] In the above-mentioned device for preparing fancy ring-spun yarn, the lifting mechanism comprises a pressurizing arm, a connecting rod, and a pressurizing cylinder;

[0029] The pressurizing arm is parallel to the left and right directions, and the non-end position is connected to the upper roller located below it through a connecting rod, and the middle position is connected to the pressurizing cylinder located above it, and the pressurizing direction of the pressurizing cylinder is downward;

[0030] A sliding sleeve is provided at each of the left and right ends of the pressure arm, and the two sliding sleeves are respectively sleeved on the middle section of a vertically arranged support rod. A support seat is provided at the lower end of each of the two support rods, and a spring is sleeved on the lower section of each of the two support rods. On the same support rod, the spring is clamped between the sliding sleeve and the support seat.

[0031] When the pressure cylinder is pressurized, it will push the pressure arm downward, and the sliding sleeve connected to it will also slide downward along the support rod and compress the spring, and the upper roller connected to it will also move downward; when the pressure cylinder stops pressurizing, the spring is compressed, and under the action of the elasticity and recovery of the spring, the sliding sleeve moves upward and drives the pressure arm to return to its initial position.

[0032] In the above-mentioned ring-spun fancy yarn preparation device, the stroke of the pressurizing cylinder is 5-10 mm, and the thrust is 1000-1500 N.

[0033] In the above-mentioned device for preparing a ring-spun fancy yarn, the spring is a carbon steel spring with a diameter of 40-45 mm, a wire diameter of 2-3 mm, a number of turns of 15-20, a length of 80-120 mm, and an elastic coefficient of 200-250 N / mm.

[0034] In the preparation device of the ring-spun fancy yarn as described above, the diameter of the intermittently fed rear roller is 25~38mm, the diameter of the middle roller is 25~38mm, the diameter of the front roller is 25~38mm, the diameter of the bottom roller is 6~8mm, and the diameter of the top roller is 6~8mm.

[0035] In the above-mentioned device for preparing fancy ring-spun yarn, when the height of the upper roller is maximum, the vertical distance between the central axes of the upper roller and the lower roller is 18-22 mm.

[0036] In the above-mentioned ring-spun fancy yarn preparation device, the middle of the upper roller is made of metal material and the surface layer is made of nitrile rubber.

[0037] In the device for preparing fancy ring spinning yarn as described above, the ring spinning frame further comprises a continuous feeding rear roller.

[0038] Principle of the invention:

[0039] In the spinning process of the present invention, the fiber strands in the roving are subjected to the force of the intermittent feeding rear roller and the middle roller in the post-drafting zone between the intermittent feeding rear roller and the middle roller. The effect, force Between the intermittent feeding rear roller and the middle roller; when the middle roller completes the drafting of the fiber strands, the force Hold the fiber strands and work together with the intermittent feeding rear roller to make the fiber strands move toward the middle roller jaws. When the fiber strands move to the range controlled by the friction force of the middle roller, they stop moving forward. When the roving is fed again, the force Without acting on the fiber whiskers, the intermittent feeding rear roller starts to feed cotton forward, and at this time the middle roller will re-draft the fiber whiskers. Since the head end of the fiber whiskers has entered the range controlled by the friction force of the middle roller during the period from the stop of drafting to the start of drafting of the roving passing through the rear drafting zone, when the roving is again drafted by the middle roller, the head end of the fiber will immediately change speed and enter the jaws of the middle roller, thereby reducing the average length of the transition section of the spun fancy yarn, making the transition section of the fancy yarn less obvious, which is conducive to strengthening the three-dimensional style of the fabric woven by the fancy yarn; at the same time, the spinning method of the ring-spun fancy yarn of the present invention can also reduce the probability of the appearance of details in the transition section of the spun fancy yarn, improve the yarn dryness level of the spun yarn, and improve the quality level of the yarn.

[0040] Beneficial effects:

[0041] In the preparation process of ring-spun fancy yarn, the present invention adjusts the distance between the head end of the fiber strand and the jaws of the middle roller by feeding the head end of the fiber strand into the range controlled by the friction force boundary of the middle roller, thereby effectively solving the detail problem generated in the transition section when two coarse yarns are alternately fed or one coarse yarn is intermittently fed in the prior art, avoiding the empty distance caused by the roller stopping rotation after intermittent feeding, thereby improving the quality and appearance quality of the ring-spun fancy yarn. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 Schematic diagram of the ring spinning fancy yarn spinning method of Example A1;

[0043] Figure 2 A schematic diagram of the structure of the device used for preparing ring-spun fancy yarn;

[0044] Figure 3 It is a structural schematic diagram of the lifting mechanism;

[0045] Figure 4 It is a schematic diagram of the movement of the roller in a single cycle after intermittent feeding;

[0046] Among them, 1-first roving, 2-second roving, 3-intermittent feeding rear roller, 4-middle roller, 5-lifting mechanism, 6-controller, 51-support rod, 52-sliding sleeve, 53-spring, 54-pressure arm, 55-pressure cylinder, 56-connecting rod, 57-upper roller, 58-lower roller. DETAILED DESCRIPTION

[0047] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0048] The following are the test methods for the relevant performance indicators in each embodiment and comparative example:

[0049] Average length of transition segment: randomly select 20 transition segments and take the average value.

[0050] Number of details: Tested in accordance with GB / T 3292.1-2008 standard.

[0051] The following embodiments are used to prepare the fancy yarns of ring spinning, such as Figure 2~Figure 3 As shown, it includes a ring spinning frame, an upper roller 57, a lower roller 58, a controller 6, and a lifting mechanism 5;

[0052] like Figure 2 As shown, the ring spinning frame includes an intermittent feeding rear roller 3, a middle roller 4, and a front roller, or the ring spinning frame also includes a continuous feeding rear roller;

[0053] like Figure 3 As shown, the central axes of the upper roller 57 and the lower roller 58 are parallel to the left-right direction, the upper roller 57 is located above the lower roller 58, and the upper roller 57 and the lower roller 58 are located between the intermittent feeding rear roller 3 and the middle roller 4 at the same time; the diameter of the intermittent feeding rear roller 3 is 25-38 mm, the diameter of the middle roller 4 is 25-38 mm, the diameter of the front roller is 25-38 mm, the diameter of the lower roller 58 is 6-8 mm, and the diameter of the upper roller 57 is 6-8 mm; the middle of the upper roller 57 is made of metal material, and the surface layer is nitrile rubber;

[0054] The controller 6 controls the operation of the intermittent feeding rear roller 3, the middle roller 4, the front roller and the bottom roller 58, and adjusts the height of the top roller 57 through the lifting mechanism 5; when the height of the top roller 57 is the minimum, the distance between the top roller 57 and the bottom roller 58 is 0; when the height of the top roller 57 is the maximum, the vertical distance between the center axes of the top roller 57 and the bottom roller 58 is 18-22 mm;

[0055] The lifting mechanism 5 includes a pressurizing arm 54, a connecting rod 56, and a pressurizing cylinder 55; the pressurizing arm 54 is parallel to the left and right directions, and the non-end position is connected to the upper roller 57 located below it through the connecting rod 56, and the middle position is connected to the pressurizing cylinder 55 located above it, and the pressurizing direction of the pressurizing cylinder 55 is downward; a sliding sleeve 52 is respectively provided at the left and right ends of the pressurizing arm 54, and the two sliding sleeves 52 are respectively sleeved on the middle section of a vertically arranged support rod 51, and the lower ends of the two support rods 51 are respectively A support seat is provided, and a spring 53 is sleeved on the lower section of each of the two support rods 51. On the same support rod 51, the spring 53 is clamped between the sliding sleeve 52 and the support seat; the stroke of the pressurizing cylinder 55 is 5-10mm, and the thrust is 1000-1500N; the spring 53 is a carbon steel spring, with a diameter of 40-45mm, a wire diameter of 2-3mm, a number of turns of 15-20, a length of 80-120mm, and an elastic coefficient of 200-250N / mm;

[0056] When the device is used to prepare the ring-spun fancy yarn, the fiber strands fed from the intermittent feeding rear roller 3 are placed between the intermittent feeding rear roller 3 and the middle roller 4. At this time, the upper roller 57 is at the highest point and maintains a certain initial spacing with the lower roller 58.

[0057] Subsequently, the controller 6 starts the operation process of the intermittently feeding rear roller 3, the middle roller 4 (continuously rotating forward at a linear speed of v3), the front roller (continuously rotating forward at a linear speed of v4) and the bottom roller 58; wherein the intermittently feeding rear roller 3 is in periodic motion, such as Figure 4 As shown, the start time of a single cycle is recorded as t1, the end time is recorded as t3, and there are four increasing times between t1 and t3, which are recorded as t2, ta, and tb respectively; in the [t1, t2) stage, the roller 3 rotates forward at a linear speed of v1 after intermittent feeding; in the [t2, ta) stage, the roller 3 does not rotate after intermittent feeding; in the [ta, tb) stage, the controller 6 controls the pressurizing cylinder 55 to pressurize downward, and the pressurizing cylinder 55 pushes the pressurizing arm 54 through the connecting rod 56 to move the upper roller 57 downward and work together with the lower roller 58. , tightly holding a point on the roving in the rear drafting zone, and at the same time controlling the lower roller 58 and the intermittent feeding rear roller 3 to rotate forward at the same linear speed v2; in the [tb, t3) stage, the lower roller 58 and the intermittent feeding rear roller 3 stop rotating; at time t3, the pressurizing cylinder 55 stops pressurizing, and the upper roller 57 gradually bounces up to the highest point under the elastic force of the spring 53, no longer holding the fiber strands, and the intermittent feeding rear roller 3 enters the next periodic motion, rotating forward at the linear speed of v1, and continues to prepare ring-spun fancy yarn.

[0058] Example A1

[0059] A method for preparing a ring-spun fancy yarn, the specific steps are as follows:

[0060] (1) Preparation of raw materials;

[0061] The first roving and the second roving are made of cotton and the main length is 30mm;

[0062] (2) Design of roving feeding method;

[0063] like Figure 1 As shown, the first roving 1 is intermittently fed by the intermittent feeding rear roller 3 of the device, and the second roving 2 is continuously fed by the middle roller 4 of the device;

[0064] (3) starting a device to prepare ring-spun fancy yarn;

[0065] Among them, the relevant parameters of the device are: the diameter of the intermittent feeding rear roller is 25mm; the diameter of the middle roller is 25mm; the diameter of the front roller is 25mm; the diameter of the bottom roller is 6mm; the diameter of the top roller is 6mm; when the height of the top roller is the maximum, the vertical distance between the center axes of the top roller and the bottom roller is 18mm; the distance between the bottom roller jaws and the intermittent feeding rear roller jaws is 10mm less than the main body length of the first roving; the distance between the bottom roller jaws and the middle roller jaws is 15mm less than the main body length of the first roving; the distance between the middle roller jaws and the front roller jaws is 35mm;

[0066] Relevant process parameters: spindle speed is 12000r / min; spinning count is 21 ne; twist is 550 twists / m; the first roving weight is 6g / 10m; the second roving weight is 6g / 10m; v1 is 0.8m / min; v2 is 10mm / s; v3 is 0.96m / min; v4 is 21.8m / min; the interval between t2 and t1 is 3s; the interval between ta and t2 is 0.3s; the interval between tb and ta is 0.2s; the interval between t3 and tb is 0.1s.

[0067] The final ring-spun fancy yarn is a ring-spun slub yarn, and the average length of the transition section is 3 mm.

[0068] Example A2

[0069] A method for preparing a ring-spun fancy yarn, the specific steps are as follows:

[0070] (1) Preparation of raw materials;

[0071] The first roving and the second roving are made of viscose and the main length is 38mm;

[0072] (2) Design of roving feeding method;

[0073] The first roving is intermittently fed by the intermittent feeding rear roller of the device, and the second roving is continuously fed by the middle roller of the device;

[0074] (3) starting a device to prepare ring-spun fancy yarn;

[0075] Among them, the relevant parameters of the device are: the diameter of the intermittent feeding rear roller is 28mm; the diameter of the middle roller is 28mm; the diameter of the front roller is 28mm; the diameter of the bottom roller is 6mm; the diameter of the top roller is 6mm; when the height of the top roller is the maximum, the vertical distance between the center axes of the top roller and the bottom roller is 20mm; the distance between the bottom roller jaws and the intermittent feeding rear roller jaws is 8mm smaller than the main body length of the first roving; the distance between the bottom roller jaws and the middle roller jaws is 30mm smaller than the main body length of the first roving; the distance between the middle roller jaws and the front roller jaws is 43mm;

[0076] Relevant process parameters: spindle speed is 13000r / min; spinning count is 32 English count; twist is 680 twists / m; the first roving weight is 5.5g / 10m; the second roving weight is 5.5g / 10m; v1 is 0.64m / min; v2 is 15mm / s; v3 is 0.83m / min; v4 is 19.1m / min; the interval between t2 and t1 is 5s; the interval between ta and t2 is 0.4s; the interval between tb and ta is 0.13s; the interval between t3 and tb is 0.15s.

[0077] The final ring-spun fancy yarn is a ring-spun segment colored yarn, the number of thin segments is 2 / km, and the average length of the transition segment is 4 mm.

[0078] Example A3

[0079] A method for preparing a ring-spun fancy yarn, the specific steps are as follows:

[0080] (1) Preparation of raw materials;

[0081] The first roving and the second roving are made of polyester and the main length is 55mm;

[0082] (2) Design of roving feeding method;

[0083] The first roving is intermittently fed by the intermittent feeding rear roller of the device, and the second roving is continuously fed by the middle roller of the device;

[0084] (3) starting a device to prepare ring-spun fancy yarn;

[0085] Among them, the relevant parameters of the device are: the diameter of the intermittent feeding rear roller is 38mm; the diameter of the middle roller is 38mm; the diameter of the front roller is 38mm; the diameter of the bottom roller is 8mm; the diameter of the top roller is 8mm; when the height of the top roller is the maximum, the vertical distance between the center axes of the top roller and the bottom roller is 22mm; the distance between the bottom roller jaws and the intermittent feeding rear roller jaws is 15mm smaller than the main body length of the first roving; the distance between the bottom roller jaws and the middle roller jaws is 30mm smaller than the main body length of the first roving; the distance between the middle roller jaws and the front roller jaws is 60mm;

[0086] Relevant process parameters: spindle speed is 15000r / min; spinning count is 40 English count; twist is 800 twists / m; the first roving weight is 5g / 10m; the second roving weight is 5g / 10m; v1 is 0.55m / min; v2 is 20mm / s; v3 is 0.8m / min; v4 is 18.75m / min; the interval between t2 and t1 is 8s; the interval between ta and t2 is 0.5s; the interval between tb and ta is 0.1s; the interval between t3 and tb is 0.2s.

[0087] The final ring-spun fancy yarn is a ring-spun segment colored yarn, the number of thin segments is 1 / km, and the average length of the transition segment is 5 mm.

[0088] Comparative Example A1

[0089] A method for preparing a ring-spun fancy yarn is basically the same as that of Example A3, except that the device used does not include an upper roller, a lower roller, or a lifting mechanism, and between time t2 and time t3, the intermittent feeding rear roller never rotates, nor does it hold a point on the roving in the rear drafting zone and move forward.

[0090] The final ring-spun fancy yarn is a ring-spun segment colored yarn, the number of thin segments is 3.2 / km, and the average length of the transition segment is 9 mm.

[0091] Example B1

[0092] A method for preparing a ring-spun fancy yarn, the specific steps are as follows:

[0093] (1) Preparation of raw materials;

[0094] The first roving and the second roving are made of cotton and the main length is 30mm;

[0095] (2) Design of roving feeding method;

[0096] The first roving is intermittently fed by the intermittent feeding rear roller of the device, and the second roving is continuously fed by the continuous feeding rear roller of the device;

[0097] (3) starting a device to prepare ring-spun fancy yarn;

[0098] Among them, the relevant parameters of the device are: the diameter of the intermittent feeding rear roller is 25mm; the diameter of the continuous feeding rear roller is 25mm; the diameter of the middle roller is 25mm; the diameter of the front roller is 25mm; the diameter of the bottom roller is 6mm; the diameter of the top roller is 6mm; when the height of the top roller is the maximum, the vertical distance between the center axes of the top roller and the bottom roller is 18mm; the distance between the bottom roller jaws and the intermittent feeding rear roller jaws is 10mm less than the main body length of the first roving; the distance between the bottom roller jaws and the middle roller jaws is 15mm less than the main body length of the first roving; the distance between the continuous feeding rear roller jaws and the middle roller jaws is 35mm; the distance between the middle roller jaws and the front roller jaws is 35mm;

[0099] Relevant process parameters: spindle speed is 12000r / min; spinning count is 21 ne; twist is 550 twists / m; the first roving weight is 6g / 10m; the second roving weight is 6g / 10m; v1 is 0.8m / min; v2 is 10mm / s; v3 is 0.96m / min; v4 is 21.8m / min; the interval between t2 and t1 is 3s; the interval between ta and t2 is 0.3s; the interval between tb and ta is 0.2s; the interval between t3 and tb is 0.1s.

[0100] The final ring-spun fancy yarn is a ring-spun slub yarn, and the average length of the transition section is 3 mm.

[0101] Example B2

[0102] A method for preparing a ring-spun fancy yarn, the specific steps are as follows:

[0103] (1) Preparation of raw materials;

[0104] The first roving and the second roving are made of viscose and the main length is 38mm;

[0105] (2) Design of roving feeding method;

[0106] The first roving is intermittently fed by the intermittent feeding rear roller of the device, and the second roving is continuously fed by the continuous feeding rear roller of the device;

[0107] (3) starting a device to prepare ring-spun fancy yarn;

[0108] Among them, the relevant parameters of the device are: the diameter of the intermittent feeding rear roller is 28mm; the diameter of the continuous feeding rear roller is 28mm; the diameter of the middle roller is 28mm; the diameter of the front roller is 28mm; the diameter of the bottom roller is 6mm; the diameter of the top roller is 6mm; when the height of the top roller is the maximum, the vertical distance between the center axes of the top roller and the bottom roller is 20mm; the distance between the bottom roller jaws and the intermittent feeding rear roller jaws is 8mm smaller than the main body length of the first roving; the distance between the bottom roller jaws and the middle roller jaws is 30mm smaller than the main body length of the first roving; the distance between the continuous feeding rear roller jaws and the middle roller jaws is 45mm; the distance between the middle roller jaws and the front roller jaws is 43mm;

[0109] Relevant process parameters: spindle speed is 13000r / min; spinning count is 32 English count; twist is 680 twists / m; the first roving weight is 5.5g / 10m; the second roving weight is 5.5g / 10m; v1 is 0.64m / min; v2 is 15mm / s; v3 is 0.83m / min; v4 is 19.1m / min; the interval between t2 and t1 is 5s; the interval between ta and t2 is 0.4s; the interval between tb and ta is 0.13s; the interval between t3 and tb is 0.15s.

[0110] The final ring-spun fancy yarn is a ring-spun segment colored yarn, the number of thin segments is 2 / km, and the average length of the transition segment is 4 mm.

[0111] Example B3

[0112] A method for preparing a ring-spun fancy yarn, the specific steps are as follows:

[0113] (1) Preparation of raw materials;

[0114] The first roving and the second roving are made of polyester and the main length is 55mm;

[0115] (2) Design of roving feeding method;

[0116] The first roving is intermittently fed by the intermittent feeding rear roller of the device, and the second roving is continuously fed by the continuous feeding rear roller of the device;

[0117] (3) starting a device to prepare ring-spun fancy yarn;

[0118] Among them, the relevant parameters of the device are: the diameter of the intermittent feeding rear roller is 38mm; the diameter of the continuous feeding rear roller is 38mm; the diameter of the middle roller is 38mm; the diameter of the front roller is 38mm; the diameter of the bottom roller is 8mm; the diameter of the top roller is 8mm; when the height of the top roller is the maximum, the vertical distance between the center axes of the top roller and the bottom roller is 22mm; the distance between the bottom roller jaws and the intermittent feeding rear roller jaws is 15mm less than the main body length of the first roving; the distance between the bottom roller jaws and the middle roller jaws is 30mm less than the main body length of the first roving; the distance between the continuous feeding rear roller jaws and the middle roller jaws is 65mm; the distance between the middle roller jaws and the front roller jaws is 60mm;

[0119] Relevant process parameters: spindle speed is 15000r / min; spinning count is 40 English count; twist is 800 twists / m; the first roving weight is 5g / 10m; the second roving weight is 5g / 10m; v1 is 0.55m / min; v2 is 20mm / s; v3 is 0.8m / min; v4 is 18.75m / min; the interval between t2 and t1 is 8s; the interval between ta and t2 is 0.5s; the interval between tb and ta is 0.1s; the interval between t3 and tb is 0.2s.

[0120] The final ring-spun fancy yarn is a ring-spun segment colored yarn, the number of thin segments is 1 / km, and the average length of the transition segment is 5 mm.

[0121] Comparative Example B1

[0122] A method for preparing a ring-spun fancy yarn is basically the same as that of Example B3, except that the device used does not include an upper roller, a lower roller, or a lifting mechanism, and between time t2 and time t3, the intermittent feeding rear roller never rotates, nor does it hold a point on the roving in the rear drafting zone and move forward.

[0123] The final ring-spun fancy yarn is a ring-spun segment colored yarn, the number of thin segments is 3 / km, and the average length of the transition segment is 8 mm.

Claims

1. A method for preparing a ring-spun fancy yarn, wherein two or more rovings are spun together using a ring spinning frame, wherein the ring spinning frame comprises an intermittently fed rear roller (3), a middle roller (4), and a front roller, wherein: At least one roving is intermittently fed by an intermittent feeding rear roller (3), characterized in that the ring spinning frame further comprises an upper roller, a lower roller, a controller, and a lifting mechanism; The central axes of the upper roller and the lower roller are parallel to the left and right directions, the upper roller is located above the lower roller, and the upper roller and the lower roller are located between the intermittent feeding rear roller and the middle roller at the same time; When the coarse yarn in the rear stretching zone stops being stretched, the force between the upper roller and the lower roller holds the fiber strands and works together with the intermittent feeding rear roller to move the fiber strands toward the jaws of the middle roller, sending the head end of the fiber strands into the range controlled by the friction force of the middle roller (4), so that the distance between the head end of the fiber strands and the jaws of the middle roller (4) is 2 to 3 mm.

2. The method for preparing a ring-spun fancy yarn according to claim 1, characterized in that: After intermittent feeding, the roller (3) exhibits periodic motion, the start time of a single cycle is recorded as t1, the end time is recorded as t3, and there are three increasing times between t1 and t3, which are recorded as t2, ta, and tb respectively; Between the time t1 and the time t2, the intermittent feeding rear roller (3) rotates forward at a linear speed of v1; between the time t2 and the time ta, the intermittent feeding rear roller (3) does not rotate; between the time ta and the time tb, the intermittent feeding rear roller (3) rotates forward at a linear speed of v2; between the time tb and the time t3, the intermittent feeding rear roller (3) does not rotate; Between time t1 and time ta, the roving in the rear drafting zone is subjected to the drafting action; between time ta and time t3, the roving in the rear drafting zone stops being subjected to the drafting action; At time ta, a point on the roving in the rear drafting zone is gripped and moves forward at a speed of v2, stops moving forward at time tb, and stops gripping at time t3; the gripping force is greater than the pressure between the middle roller (4) and the middle top roller; At time ta, the distance between the gripping point and the jaws of the intermittent feeding rear roller (3) and the distance between the gripping point and the jaws of the middle roller are both smaller than the main length of the roving in the rear drafting zone.

3. The method for preparing a ring-spun fancy yarn according to claim 2, characterized in that: The interval between time ta and time t2 is 0.3 to 0.5 s.

4. The method for preparing a ring-spun fancy yarn according to claim 2, characterized in that: The interval between time tb and time ta is 0.1 to 0.2 s, and v2 is 10 to 20 mm / s.

5. The method for preparing a ring-spun fancy yarn according to claim 2, characterized in that: The interval between time t3 and time tb is 0.1 to 0.2 s.

6. The method for preparing a ring-spun fancy yarn according to claim 2, characterized in that: At time ta, the distance between the gripping point and the jaws of the intermittent feeding rear roller (3) is 20-40 mm, and the distance between the gripping point and the jaws of the middle roller is 15-25 mm; the main length of the roving in the rear drafting zone is 30-55 mm.

7. The method for preparing a ring-spun fancy yarn according to claim 1, characterized in that: The other rovings are fed continuously by the middle roller (4).

8. The method for preparing a ring-spun fancy yarn according to claim 1, characterized in that: The ring spinning frame also includes a continuous feed rear roller, and other rovings are continuously fed by the continuous feed rear roller.

9. The method for preparing a ring-spun fancy yarn according to any one of claims 1 to 8, characterized in that: The ring-spun fancy yarn is a ring-spun segment colored yarn or a ring-spun slub yarn, the average length of the transition section is 3 to 5 mm, and the number of details of the ring-spun segment colored yarn is 1 to 2 per km.

Images