Technical field
[0001] The present invention relates the field of rotor spinning in the textile industry.
Background
[0002] The basic principle of the rotor spinning yarn is that the sliver is fed through
the trumpet and is held by feeding plate and a feeding roller. The feeding roller
rotates to feed the sliver to the carding area. The sliver is opened and stripped,
carded separately and mixed by the carding roller, which rotates at a high speed in
the carding area, so that the sliver becomes single fibers which are separated and
arranged parallel to each other. The single fibers enter into a fiber transport channel.
Under the action of air flow, the fiber flows into the rotor through the fiber transport
channel. With the centrifugal force of the rapidly rotating rotor, the fibers in the
groove are further piled up and mixed, and then the fibers are jointed with the mother-yarn
and twisted by a navel to form a yarn.
[0003] In the Patent "Rotor spinning melange yarn forming method and device and product
(Application No.
CN201410190891.1)" and " Device of spinning rotor spun melange yarn (
CN201420229715.X)", the speed of the feeding roller is controlled to keep feeding in an invariable
amount, or two or more drafted slivers are fed in segments in different amounts, resulting
in that the blending ratio has monochromatic or multi-colored fibers mixture, so as
to achieve an effect that the blending ratio can be adjusted while the density of
the spun yarn is invariable. However, these two inventions have two problems. First,
in those inventions, only the concept of realizing the blending and segment-color
spinning process with invariable linear density through the proposed coupling and
drafting method, and no indication is given to show how to change the mixing ratio
or color blending ratio under the condition that the coupling and drafting achieves
an invariable linear density. In the meantime, no specific embodiments and examples
are disclosed. Second, a conventional single carding roller is still used in those
patent applications. When three slivers are fed at the same time, the original carding
and drafting system cannot adequately strip, card, separate and mix a plurality of
slivers, which will cause inadequate break down of fiber strands, resulting in blocking
the carding roller and rotor, and will be prone to yarn broken and slub, nep and other
defects. At the same time, although the total amount of each sliver by coupling and
feeding is invariable, there is still a difference in the feeding amount of each sliver,
and the short carding area causes little chance of horizontal fiber mixing, resulting
in unsatisfactory color blending effect.
[0004] At present, the patent "Method and equipment for rotor spun slub yarn" (patent number
CN00137211.4) can achieve invariable blending ratio but the linear density changes during the
rotor spinning process. The principle of the patent is that the asynchronous motor
and the stepper motor drive feeding roller through the differential, screw and worm
wheel. The stepper motor, under the control of the intelligent controller, performs
the following operations: reducing from high speed to low speed; continuing to run
for a period of time; accelerating to high speed; continuing to run for a period of
time, and the rotor spins a segment of slub yarn. The patent can produce a yarn with
variable densities but cannot change blending ratios of the yarn.
[0005] The production of the yarn with the linear density and blending ratio both changed,
requires not only that the feeding amount of the two or more of the fed roving can
be controlled separately on line, but also that the total amount of the fed roving
can be controlled when the feeding amount of the roving is changed. There is no prior
art that discloses the production of such yarn. The main problem of the existing rotor
spinning technology which can produce the yarn having an invariable linear density
and blending ratio is that it is impossible to blend two or more fibers in any proportion
during the rotor spinning process.
Summary of the Invention
[0006] In order to solve the above problem, the present invention improves the structure
of the conventional rotor spinning machine. A device for implementing a rotor spinning
method with three-level carding and multi-component feeding, includes a spinning system
and a computer control system. The spinning system comprises a feeding and carding
mechanism, a collecting and twisting mechanism, and a winding mechanism. The device
is characterized in that the feeding and carding mechanism comprises five combined
feeding rollers with rotational freedom degrees, and a three-level carding roller.
The speed ratio of the five combined feeding rollers with rotational freedom degree
can be adjusted. The collecting and twisting mechanism include a fiber transport channel,
a rotor, and a yarn guider. The winding mechanism includes a couple of guide rollers
and a winding mechanism. The computer control system includes a PLC programmable controller,
a servo driver, and a servo motor. The five combined feeding rollers with rotational
freedom degrees and the three-level carding roller are driven by the servo motor.
The combined feeding rollers with five rotational freedom degrees comprises a shaft,
a bearing, a hollow shaft, a first gear, a second gear, a third gear, a fourth gear,
a fifth gear, a washer, a first movable roller, a second movable roller, a third movable
roller, a fourth movable roller, and a fifth movable roller. The first to fifth gears
and the first to fifth movable rollers rotate around the same axis. The first to fifth
gears respectively drive the first to fifth movable rollers. The three-level carding
roller comprises the first carding roller, the second carding roller and the third
roller that are arranged in parallel. The rotation speed of the three-level carding
roller is progressively increased from the first level to the third level. The rotation
speed of the first carding roller is 1500-3000 rpm, the rotation speed of the second
carding roller is 3000-6000 rpm, and the rotation speed of the third carding roller
is 6000-12000 rpm. The density of carding needles of the three-level carding roller
progressively increases from the first carding roller to the third carding roller.
[0007] The other objective of the present invention is to provide a rotor spinning method
using the above device. The method includes cotton feeding, carding, collecting and
twisting, guide and winding. The method is characterized in that combined feeding
rollers with five rotational freedom degrees are used in the fiber feeding to feed
the fiber into the carding area asynchronously, and three-level carding roller is
used in the carding process.
[0008] With the combined rollers and the three-level carding roller configured in the present
invention, five slivers (or five different raw material slivers, or five kinds of
colored slivers, hereinafter referred to as five components) can be asynchronously
fed into the rotor spinning and carding area through the combined feeding rollers.
After opening, carding, orienting, separating and mixing by the three-level carding
roller, the five slivers are gradually combed into bundle fibers and further combed
into single fibers. Under the action of centrifugal force and air flow, a continuous
flow comprised by single fibers released and transferred from the carding roller enters
into the rotor rotating at a high speed. In the rotor, the fiber flow, under the centrifugal
force, is collected together into a sliver again, and then twisted by the navel, and
then guided by the guide roller to form the rotor spinning yarn. In the process of
spinning, the servo driving system is controlled by a computer program to feed five
slivers asynchronously to the carding area by feeding rollers having five freedom
degrees. By controlling the feeding amount and feeding ratio of the five feeding rollers,
it is possible to dynamically configure the final yarn density of the rotor spinning
and the blending ratio of the five components to produce slub yarn, segment-color
yarn, segment-color slub yarn, and melange yarn.
[0009] The speed of the first carding roller is low, so that it is ensured that when the
plurality of the slivers with great difference are fed, the total number of carding
fibers of each sliver carded by the carding roller are within a reasonable range,
thereby reducing damage to the fiber. The speed of the second carding roller is higher
than that of the first carding roller. After being carded by the second carding roller,
the longitudinal orientation of the fiber is optimized, horizontal transfer mixing
of the fiber is further optimized. The third carding roller is a high-speed carding
roller. The fiber, after being carded by the third carding roller, obtains not only
a better carding and transfer, but also the transport speed is improved, thereby meeting
the requirement of centrifugal force for entering the fiber transport channel. Therefore,
the fiber can smoothly and orderly go into the rotor to form yarns. Through the multi-level
stripping, opening, cleaning, carding, separating and transferring, the large-scale
drafting function where the slivers are combed into web, which is then combed into
bundles of fibers, which are then separated as single fibers is successfully completed,
which enhances the function of the carding area of the rotor spinning, providing flexibility,
high efficiency, and high yield.
(2) Based on the mechanical innovation design, the present invention constructs the
corresponding mathematical model of spinning and the algorithm of the program. Through
the mechatronic servo control system, the random control of the linear density and
blending ratio of the rotor spinning yarn are achieved. In specific embodiments, the
four kinds of spinning yarns are shown as following:
① a yarn with invariable linear density and variable blending ratio, such as gradient-color
or segment-color yarn with an invariable linear density segment;
② a yarn with invariable blending ratio and variable linear density, such as slub
yarn, big-belly yarn, dot yarn;
③ a yarn with variable linear density and variable blending ratio, such as segment-color
slub yarn, segment-color big-belly yarn, segment-color dot yarn;
④ a yarn with invariable linear density and invariable blending ratio but mixed with
any proportion of blended yarn or color-mixed yarn.
Brief Description of the drawings
[0010]
FIG.1 is a flowchart of the rotor spinning.
FIG.2 is a diagram of the carding and drafting process of the rotor spinning method
with three-level carding roller.
FIG.3 is a diagram showing the transmission of the feeding roller, wherein 3b is the
right-side view of 3a.
FIG.4 is a structural view of the combined feeding roller.
FIG.5 is a diagram of a spinning control system with five components asynchronous
fed and carded.
FIG.6 is a diagram of a control model of a rotor spinning yarn system with five components
asynchronous input.
1-1, 1-2, 1-3: carding roller; 1-4, 1-5: trash ejection port; 1-6: feeding roller;
1-7: sliver; 1-8: compression spring; 1-9: feeding plate; 1-10: fiber transport channel;
1-11: navel; 1-12: rotor; 1-13: degassing hole; 1-14, 1-15: guide roller, 1-16: yarn;
2-6, 2-7, 2-8, 2-9, 2-10: feeding roller; 2-1, 2-2, 2-3, 2-4, 2-5: sliver; 2-11: feeding
plate; 2-12, 2-13, 2-14: carding roller; 2-15: fiber flow; 2-16: rotor; 2-17: yarn;
3a-5, 3a-6, 3a-7, 3a-8, 3a-9: rollers; 3a-1, 3a-2, 3a-14, 3a-15, 3a-16: gears; 3a-3,
3a-4, 3a-10, 3a-11, 3a-12: idler gear; 3a-13: roller shaft; 3a-17, 3a-18, 3a-19: carding
roller, 3a-20: spun yarn, 3b-1: gear; 3b-2: roller; 3b-3, 3b-4, 3b-5, 3b-6, 3b-7:
gears;
4-1, 4-2, 4-3, 4-4, 4-5: rollers; 4-6, 4-7, 4-13, 4-14, 4-17: gears; 4-8, 4-12, 4-16:
key; 4-9: fixed shaft sleeve; 4-10: screw; 4-11: bearing; 4-15: shaft. Five movable
roller (4-1, 4-2, 4-3, 4-4, 4-5) are driven by the gears (4-6, 4-7, 4-13, 4-14, 4-17)
respectively.
Detailed Description of the Embodiments
[0011] The meaning of the formula used in the text:
V01: linear velocity of the feeding roller 1; V02: linear velocity of the feeding roller 2; V03: linear velocity of the feeding roller 3; V04: linear velocity of the feeding roller 4; V05: linear velocity of the feeding roller 5; V1: the linear velocity of the carding roller 1; V2: the linear velocity of the carding roller 2; V3: the linear velocity of the carding roller 3; V4: the linear speed of the rotor; V5: the linear velocity of the guide roller.
ρ1: linear density of sliver A (g / m)
ρ2: linear density of sliver B (g / m)
ρ3: linear density of sliver C (g / m)
ρ4: linear density of sliver D (g / m)
ρ5: linear density of sliver E (g / m)
p: yarn density (g / m);
ρ11: linear density of the sliver A passing through the carding roller 1 (g / m)
ρ12: linear density of the sliver A passing through the carding roller 2 (g / m)
ρ13: linear density of the sliver A passing through the carding roller 3 (g / m)
ρ14: linear density of the sliver A in the rotor (g / m)
ρ21: linear density of the sliver B passing through the carding roller 1 (g / m)
ρ22: linear density of the sliver B passing through the carding roller 2 (g / m)
ρ23: linear density of the sliver B passing through the carding roller 3 (g / m)
ρ24: linear density of the sliver B in the rotor (g / m)
ρ31: linear density of the sliver C passing through the carding roller 1 (g / m)
ρ32: linear density of the sliver C passing through the carding roller 2 (g / m)
P33: linear density of the sliver C passing through the carding roller 3 (g / m)
ρ34: sliver C linear density in the rotor (g / m)
ρ41: linear density of the sliver D passing through the carding roller 1 (g / m)
ρ42: linear density of the sliver D passing through the carding roller 2 (g / m)
ρ43: linear density of the sliver D passing through the carding roller 3 (g / m)
ρ44: linear density of the sliver D in the rotor (g / m)
ρ51: linear density of the sliver E passing through the carding roller 1 (g / m)
ρ52: linear density of the sliver E passing through the carding roller 2 (g / m)
ρ53: linear density of the sliver E passing through the carding roller 3 (g / m)
ρ54: linear density of the sliver D in the rotor (g / m)
E1: draft ratio of the carding roller 1 to the feeding roller;
E2: draft ratio of the carding roller 2 to the carding roller 1;
E3: draft ratio of the carding roller 3 to the carding roller 2;
E4: draft ratio of the rotor to the carding roller 3;
E5: draft ratio of the guide roller to the rotor;
E: total draft ratio of rotor spinning, which is equal to the draft ratio of guide
roller to feeding roller.
[0012] Subscripts 1, 2, 3, 4, 5 represent component A, component B, component C, component
D, component E, respectively.
(1) three-level roller carding process design:
[0013] As to feeding a plurality of the slivers, when the feeding speeds of feeding rollers
are greatly different, the fiber holding time of each component is also greatly different.
In the rotor spinning with single carding roller, due to the need of balancing the
stripping /carding fibers, as well as the requirement of the fiber speed when transferring
to the fiber transport channel, the rotation speed of the single carding roller is
high. Therefore, when there is a significant difference in feeding amount, the number
of times that a fiber of the five slivers is carded will be significantly different,
and the more the fiber experiences carding, larger will be the damage to this fiber.
[0014] In order to solve the problem of the rotation speed of the carding roller against
the damage to fiber and the even mixture of fibers, the present invention adopts the
form of three-level carding rollers, that is, the first carding roller, the second
carding roller and the third carding roller. The rotation speed of the first carding
roller (ω = 1500-3000rpm) is relatively low, the needle density is also relatively
low; the working angle of the needle is relatively small. It is mainly configured
for stripping, opening, cleaning and carding and focusing on making the total carding
number of fibers of each sliver within a reasonable range, thereby reducing damage
to the fiber. The speed of the second carding roller (ω = 3000-6000rpm) is mainly
configured for stripping, carding, and transferring fibers, wherein the needle density
is larger than the needle density of the first carding roller, and the working angle
of the needle is relatively larger than that of the first carding roller. After being
carded by the second carding roller, the longitudinal orientation of the fiber is
optimized, and horizontal transfer mixing of the fiber is further optimized. The third
carding roller is a high-speed carding roller (ω =6000-12000 rpm), which is mainly
configured for stripping, carding and separating, and transferring fibers, wherein
the needle density is larger than the needle density of the second carding roller,
and the working angle of the needle is largest. Fibers passing through the third carding
roller gets better carding and transfer. Furthermore, due to the high speed of the
third carding roller, under the action of centrifugal force and air flow, a highly
separated and continuous fiber flow passes through the fiber transport channel and
enters orderly into the rotor to form yarns.
[0015] Through the stripping, opening, cleaning, carding, and transfer of the three-level
carding roller, the large-scale drafting function, where the slivers are combed into
web, which is then combed into fiber bundles, which are separated into single fibers,
is successful completed, which enhances the function of the carding area of the rotor
spinning, meets the special requirements for the carding of multiple slivers asynchronously
feeding into the rotor spun unit. The effects of flexibility, high efficiency, and
high yield are realized.
(2) Draft ratio of the rotor spun yarn:
(3) Linear density of rotor spun yarn:
[0017] 
(4) Blending ratio
[0018] The blending ratio of components A, B, C, D, E in the rotor spinning yarn are K
1, K
2, K
3, K4, and K
5, respectively:

(4) Dynamic linear density of rotor spun yarn
[0019] Assuming that the speed V
5 of the guide roller is invariable, the variables of feeding speed V
01, V
02, V
03, V
04 and V
05 of the five slivers are as follows:

[0020] So that the new changed linear density of rotor spun yarn is

(5) Dynamic blending ratio of rotor spun yarn is:
[0021] Assuming that: ρ
1 = ρ
2 = ρ
3 = ρ
4 = ρ
5 = ρ
0 
[0023] When V
01+V
02+V
03+V
04+V
05→V
01+ΔV
01+V
02+ΔV
02+V
03+ΔV
03+V
04+ΔV
04+V
05+ΔV
05, the blending ratio become as below:

[0024] Mixed configuration is gradient to realize different color scheme.
[0025] By changing V
01, V
02, V
03, V
04, and V
05, the blending ratio (color mixing ratio) of different fibers (different colors) in
the yarn can be changed under the condition that V
0 is kept invariable, so that k
1, k
2, k
3, k
4, and k
5 are changed between 0 ∼ 100%. In various color mixing modes of five primary colors,
the minimum increment of the color mixing ratio is 0.1, wherein the color scheme is
as follows:
Table 1 color scheme
| |
Blending Modes |
Color number |
| Monochromatic mode |
A, B, C, D, E |
5 |
| Double-color mixing mode |
AB, AC, AD, AE, BC, BD, BE, CD, CE, DE |
9*10=90 |
| Tricolor mixing mode |
ABC, BCD, CDE, DEA, EAB |
36*5=180 |
| Four-color mixing mode |
ABCD, BCDE, CDEA, DEAB, EABC |
82*5=410 |
| Five-color mixing mode |
ABCDE color mixture |
28*3-2=82 |
| |
Total |
767 |
[0026] Note: k
1+k
2+k
3+k
4+k
5 = 100% can have numerous combinations. Based on the five primary colors (five kinds
of color slivers) by coupling and drafting, color alternating, gradient color matching,
twisting and mixture, numerous color schemes can be formed. In addition, it is possible
to form a segment-color yarn having a variety of color distribution in the yarn.
(6) Random dynamic control method of the rotor spun yarn density and blending ratio
[0027] Dynamic change rate of density of rotor spun yarn is shown as below:

and

then

[0028] From the absolute increment of the linear density and relative increment of the linear
density, it can be found that the change of yarn linear density, which totally depends
on the V
01+ΔV
01, V
02+ΔV
02, V
03+ΔV
03, V
04+ΔV
04, V
05+ΔV
05, can have 11 different patterns. Therefore, there can be 11 kinds of yarn in different
forms.
- 1. A yarn with variable linear density, wherein one component of the yarn has variable
linear density and other components of the yarn have invariable linear densities.

- 2. A yarn with two components having variable linear density and other components
having invariable linear densities.

(j≠k; j=1, 2, 3, 4, 5; k=1. 2, 3, 4, 5)
- 3. A yarn with three components having variable linear density and other components
having invariable linear densities.

(j≠k≠m; j=1, 2, 3, 4, 5; k=1, 2, 3, 4, 5; m=1, 2, 3, 4, 5)
- 4. A yarn with four components having variable linear density and other components
having invariable linear densities.

(j≠k≠m≠n; j=1, 2, 3, 4, 5; k=1, 2, 3, 4, 5; m=1, 2, 3, 4, 5; n=1, 2, 3, 4, 5)
- 5. A yarn with variable linear density, wherein all components of the yarn have variable
linear densities.

- 6. A yarn with variable linear density, wherein one component of the yarn is continuous
and other components of the yarn are discontinuous.

(r=1, 2, 3, 4, 5)
- 7. A yarn with variable linear density, wherein two components of the yarn are continuous
and other components of the yarn are discontinuous.

(r≠s, r=1, 2, 3, 4, 5; s=1, 2, 3, 4, 5)
- 8. A yarn with variable linear density, wherein three components of the yarn are continuous
and other components of the yarn are discontinuous.

(r≠s≠m, r=1, 2, 3, 4, 5; s=1, 2, 3, 4, 5; m=1, 2, 3, 4, 5)
- 9. A yarn with variable linear density, wherein four components of the yarn are continuous
and other components of the yarn are discontinuous.

(r≠s≠m≠n, r=1, 2, 3, 4, 5; s=1, 2, 3, 4, 5; m=1, 2, 3, 4, 5; n=1, 2, 3, 4, 5)
- 10. A yarn with variable linear density, wherein five components of the yarn are continuous
and have variable linear densities.

- 11. The method of dynamic feed speed control of spun yarn
Because

ΔV may come from ΔV01, or come from ΔV02, ΔV03, ΔV04, ΔV05, which can be determined by the blending ratio.
Then:





1. A rotor spinning method for five-sliver asynchronous inputting and three-level carding,
characterized in that:
1) feeding fiber by combined feeding rollers with five rotational freedom degrees
into carding area where a three-level carding roller is used for carding;
2) moving the combined feeding rollers 1, 2, 3, 4, and 5 at linear speeds V01, V02, V03, V04, and V05, respectively; moving a rotor at a linear speed V4 and moving a guide roller at a linear speed V5; setting linear densities of five slivers drafted by five rollers to be ρ1, ρ2, ρ3, ρ4 and ρ5, respectively, and setting a rotor spun yarn density to be p, such that a draft ratio
of a rotor spinning yarn is as below:

a linear density of the rotor spun yarn is formed,

wherein speeds of three carding rollers are as follows: a speed of a first carding
roller is 1500-3000 rpm, a speed of a second carding roller is 3000-6000 rpm, a speed
of a third carding roller is 6000-12000 rpm,
3) blending ratios of four slivers in the rotor spinning yarn are K1, K2, K3, K4,
and K5, respectively:





4) assuming that the speed V5 of the guide roller is invariable, the variables of feeding speeds V01, V02, V03, V04 and V05 of the feeding rollers of the five slivers are respectively as follows: V01' = V01 + ΔV01, V02' = V02 + ΔV02, V03' = V03 + ΔV03, V04' = V04 + ΔV04, V05' = V05 + ΔV05, then the dynamic linear density of the rotor spun yarn is obtained according to
formula (2)

5) assuming that ρ1 = ρ2 = ρ3 = ρ4 = ρ5 = ρ0, V01+V02+V03+V04+V05 = V0, obtaining a reference blending ratio according to the formulas (3), (4), (5), (6),
(7) as

wherein, when V01+V02+V03+V04+V05→V01+ΔV01+V02+ΔV02+V03+ΔV03+V04+ΔV04+V05+ΔV05, the blending ratio becomes as below:





realizing dynamically adjustable spinning of different color blending ratios or color
mixing ratios in the yarn with different fibers or colors by controlling of V01, V02, V03, V04, Vos.
2. The method according to claim 1,
characterized in that: assuming ρ
1 = ρ
2 = ρ
3 = ρ
4 = ρ
5 = ρ
0, V
01 + V
02 + V
03 + V
04 + V
05 = V
0, obtaining a dynamic change rate of the rotor spun yarn density according to formulas
(2) and (8):

achieving a random dynamic regulation of the density and the blending ratio of the
rotor spun yarn by controlling the speed change of the four rollers.
3. The method according to claim 2,
characterized in that:

changing speed of one of the rollers to achieve a yarn with variable linear density,
wherein one component of the yarn has variable linear density and other components
of the yarn have invariable linear densities.
4. The method according to claim 2,
characterized in that:

(j≠k; j=1, 2, 3, 4, 5; k=1, 2, 3, 4, 5),
changing speed of two of the rollers to achieve a yarn with variable linear density,
wherein two components of the yarn have variable linear densities and other components
of the yarn have invariable linear densities.
5. The method according to claim 2,
characterized in that:

(j≠k≠m; j=1, 2, 3, 4, 5; k=1, 2, 3, 4, 5; m=1, 2, 3, 4, 5),
changing speed of three of the rollers to achieve yarn with variable linear density,
wherein three components of the yarn have variable linear densities and other components
of the yarn have invariable linear densities.
6. The method according to claim 2,
characterized in that:

(j≠k≠m≠n; j=1, 2, 3, 4, 5; k=1, 2, 3, 4, 5; m=1, 2, 3, 4, 5; n=1, 2, 3, 4, 5),
changing speed of four of the rollers to achieve a yarn with variable linear density,
wherein four components of the yarn have variable linear densities and other components
of the yarn have invariable linear densities.
7. The method according to claim 2,
characterized in that:

changing speed of five of the rollers to achieve a yarn with variable linear density,
wherein five components of the yarn have variable linear densities.
8. The method according to claim 2,
characterized in that:

(r=1, 2, 3, 4, 5),
a yarn with variable linear density, wherein one component of the yarn is continuous
and other components of the yarn are discontinuous.
9. The method according to claim 2,
characterized in that:

(r≠s, r=1, 2, 3, 4, 5; s=1, 2, 3, 4, 5)
a yarn with variable linear density, wherein two components of the yarn are continuous
and other components of the yarn are discontinuous.
10. The method according to claim 2,
characterized in that:

(r≠s≠m, r=1, 2, 3, 4, 5; s=1, 2, 3, 4, 5; m=1, 2, 3, 4, 5)
a yarn with variable linear density, wherein three components of the yarn are continuous
and other components of the yarn are discontinuous.
11. The method according to claim 2,
characterized in that:

(r≠s≠m≠n, r=1, 2, 3, 4, 5; s=1, 2, 3, 4, 5; m=1, 2, 3, 4, 5; n=1, 2, 3, 4, 5)
a yarn with variable linear density, wherein four components of the yarn are continuous
and other components of the yarn are discontinuous
12. The method according to claim 2,
characterized in that:

a yarn with variable linear density, wherein five components of the yarn are continuous,
and the linear density of the yarn is variable.
13. The method according to claim 2, characterized in that: in control method of dynamic feeding speed of the yarn, ΔV0 = ΔV01 + ΔV02 + ΔV03 + ΔV04 + ΔV05, change of the speed is derived from ΔV01, ΔV02, ΔV03, ΔV04 or ΔV05 and determined by the blending ratio, and then ΔV01 = K'1(V0+ΔV)-V01, ΔV02 = K'2(V0+ΔV)-V02, ΔV03 = K3(V0+ΔV)-V03, ΔV04 = K'4(V0+ΔV)-V04, ΔV05 = K'5(V0+ΔV)-V05.
14. A device for realizing the method according to any one of the preceding claims, characterized in that, the device comprises a spinning system and a computer control system, the spinning
system comprises a feeding and carding mechanism, a collecting and twisting mechanism,
and a winding mechanism, characterized in that, the feeding and carding mechanism comprises combined feeding rollers having five
rotational freedom degrees, a three-level carding roller; wherein a speed ratio of
fiver rollers of the combined feeding rollers with five rotational freedom degrees
can be adjusted, the collecting and twisting mechanism includes a fiber transport
channel, a rotor, and a guide device; the winding mechanism includes a guide and winding
mechanism; the computer control system includes a PLC programmable controller, a servo
driver, a servo motor; wherein the combined feeding rollers with five rotational freedom
degrees and the three-level carding roller are driven by the servo motor.
15. The device according to claim 10, characterized in that the combined feeding rollers with five rotational freedom degrees comprises a shaft,
a bearing, a hollow shaft, a first gear, a second gear, a third gear, a fourth gear,
a fifth gear, a washer, a first movable roller, a second movable roller, a third movable
roller, a fourth movable roller, a fifth movable roller, wherein the first to fifth
gears and the first to fifth movable rollers are rotated around the same axis, the
first to fifth gears drive the first to fifth movable rollers, respectively.