KR20180134506A - apparatus for manufacturing biodegradable cigarette filter - Google Patents

Abstract

An objective of the present invention is to simultaneously improve the flavor of cigarette smoke and harmful component filtering performance, and improve productivity. An apparatus for manufacturing a biodegradable cigarette filter comprises: a tow supply unit to supply tow of a polylactic acid fiber material; a pretension unit which is arranged on one side of the tow supply unit, and withdraws and transports the supplied tow at a preset withdrawal speed; a relay tension unit arranged in a transport direction of the tow from the pretension unit, and rotated at an increased speed in accordance with a preset pretension rate based on a limit tension rate of the polylactic acid fiber from a rotational speed corresponding to the withdrawal speed to pretension the tow; and a main tension unit arranged in a pretension direction of the tow from the relay tension unit, and rotated at an increased speed in accordance with a preset target tension rate based on a filtering rate of a filter from a rotational speed corresponding to the pretension rate; and an injection unit to press and inject the tensioned tow to manufacture a cigarette filter.

Description

An apparatus for manufacturing biodegradable cigarette filters,

Disclosed herein is a biodegradable cigarette filter manufacturing apparatus, and more particularly, to a biodegradable cigarette filter manufacturing apparatus in which productivity of a cigarette smoke filter and a harmful component filtering filter are improved while improving productivity.

Generally, a cigarette is a cigarette paper wrapped around a tobacco cigarette paper, and cigarette paper and tobacco are burned to inhale cigarette smoke. A filter is provided in the suction part to filter the harmful components of the smoke and improve the flavor of the smoke .

Presently, most commercially available filters are based on cellulose acetate fibers, and such cellulose acetate based filters require decomposition periods of up to three years depending on environmental conditions. As a result, abandoned filters themselves or toxic substances adsorbed in the filters have caused various environmental problems.

Accordingly, various biodegradable fibers replacing cellulose acetate fibers have been developed. However, it is difficult to maintain filtration performance and flavor for harmful components of smoke during manufacturing thereof, and thus commercialization of such biodegradable fibers has not been achieved.

Particularly, polylactic acid (PLA) fibers based on fermented saccharides such as corn starch have attracted attention as high productivity, low cost, and biodegradability. However, they are low in elasticity and adsorption properties, There is a problem that it is impossible to manufacture a filter having sufficient filtering performance.

That is, when a filter is manufactured based on a polylactic acid fiber, a stretching process with a high magnification is required, but the breakage of the single yarn is reduced, resulting in a low productivity. In the case of the low stretched polylactic acid fiber, There is a problem that the filtration performance is low and the flavor is lowered when smoking.

Korean Patent Publication No. 10-2004-0097355

In order to solve the above problems, the present invention provides a device for manufacturing a biodegradable cigarette filter, wherein the productivity of the cigarette smoke is improved while simultaneously improving the flavor and harmful component filtering performance.

In order to solve the above problems, the present invention provides a tow-feeding unit for feeding a tow of a poly lactic acid fiber material; A pre-tension unit provided at one side of the tow supply unit, for drawing and feeding the supplied tow at a predetermined withdrawal speed; Wherein the pulling speed of the tow is increased by a predetermined preliminary tension ratio based on a limiting pull ratio of the polylactic acid fiber from a rotation speed corresponding to the pulling speed, Relay tension section; A main tension unit disposed in the preliminary tension direction of the tow from the relay tension unit and rotated at an increased speed according to a predetermined target tension ratio based on a filtration rate of the filter from a rotation speed corresponding to the preliminary extension ratio to pull the tow; And an injection part for producing a cigarette filter by pressurizing and injecting the stretched tow. The present invention also provides an apparatus for manufacturing a biodegradable cigarette filter.

The pre-tension unit, the relay tension unit, and the main tension unit may include a driving roller connected to the rotating unit to be rotationally driven, and an interlocking roller that is rotated in contact with the outer circumferential surface of the driving roller, And a plurality of servo motors independently connected to the drive rollers so that a shift deviation between the drive rollers is controlled so as to be expanded in correspondence to the preliminary extension ratio and the target extension ratio.

The driving roller and the interlocking roller are provided on the outer circumferential surface thereof with a pressing friction layer made of an elastic material so that the tow is pressed against the outer surface of the driving roller and the interlocking roller, And a logic controller for controlling the servo motors to interlock with each other such that the relay tension portion and the main tension portion are deviated in rotation corresponding to the target tension ratio.

The pressurizing member may include a plurality of pressing protrusions extending in the circumferential direction, the pressing protrusions extending in the axial direction and having a predetermined first width in the circumferential direction, And are spaced from each other at intervals corresponding to the first width so as to be engaged with the pressing projections.

Preferably, the preliminary tension ratio is set to 40 to 60% of the critical tension ratio, and the target tension ratio is set to 150 to 300% from the unit length of the untensioned tow.

Through the above solution, the present invention provides the following effects.

First, the pre-tension due to the deviation of the pull-out speed between the pre-tension part and the relay tension part, and the pull-out speed difference between the relay tension part and the main tension part enable the poly-lactic fiber- The low surface energy inherent in polylactic acid fibers can be compensated for by the increase of the surface area according to a wide range of tensile. Thus, it is possible to produce a filter having a high filtration rate corresponding to the acetate fiber based filter while producing a filter having high biodegradability. to provide.

Second, the pull-out speed deviation between each tension portion can be flexibly changed over a wide range without the need of gears or pulleys through a plurality of servomotors independently provided on each drive roller, so that a polylactic acid fiber tow- It is possible to manufacture a general tow-based filter as well as to manufacture a filter of a different polylactic acid fiber tow which can be applied to various polylactic acid fiber tows of different physical properties, thus improving the compatibility of the device.

Third, the number of revolutions of the second driving roller corresponding to the pre-tension ratio is automatically calculated through the logic controller controlling each servo motor based on the diameter of each driving roller and the linear momentum of the first driving roller, The rotation speed of the third driving roller corresponding to the target tension ratio is automatically calculated on the basis of the linear momentum of the roller and is controlled in an interlocked manner, so that the usability of the apparatus can be improved.

Fourth, since the pressing protrusions are formed in the form of gears along the surface of the pressing friction layer of the elastic material surrounding the rollers, the tows are gripped in a zigzag shape between the interlocked pressing protrusions and can be precisely transported without slippage, Can be accurately tensioned so as to correspond to the drawing speed difference between the tension portions.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing a tow treatment process of an apparatus for producing a biodegradable cigarette filter according to an embodiment of the present invention; FIG.
2 is a side view of an apparatus for producing a biodegradable cigarette filter according to an embodiment of the present invention.
3 is a plan view of an apparatus for manufacturing a biodegradable cigarette filter according to an embodiment of the present invention.
4 is a block diagram of an apparatus for producing a biodegradable cigarette filter according to an embodiment of the present invention.
FIG. 5 is a partial view showing an apparatus for producing a biodegradable cigarette filter according to another embodiment of the present invention. FIG.

Hereinafter, an apparatus for manufacturing a biodegradable cigarette filter according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is a side view of a device for manufacturing a biodegradable cigarette filter according to an embodiment of the present invention. FIG. 3 is a side view of the apparatus for producing a biodegradable cigarette filter according to an embodiment of the present invention. FIG. 4 is a block diagram of an apparatus for manufacturing a biodegradable cigarette filter according to an embodiment of the present invention. Referring to FIG.

1 to 4, an apparatus 100 for manufacturing a biodegradable cigarette filter according to an embodiment of the present invention includes a tow supply unit 10, a pretension unit 20, a relay tension unit 30, A portion 40, a band portion 50, and an injection portion 60.

In this case, a tow of a poly lactic acid fiber is accommodated in a compressed state in the form of a bale and a tow of a short fiber form is received from the received plug. Is released to one or a plurality of strands and supplied to the pre-tension unit 20. [

The pretensioning unit 20 is provided at one side of the tow supply unit 10, and draws and feeds the supplied tow at a predetermined drawing speed.

The pretensioner 20 is provided with a pair of rollers 21 and 22 vertically arranged so that the outer circumferences of the pretensioner 20 are in contact with each other. (21, 22).

When the rollers 21 and 22 of the pre-tension unit 20 are rotated, the tows t can be continuously drawn out from the tow supply unit 10 and transported toward the relay tension unit 30. [ have.

The pretensioning unit 20 includes a first driving roller 21 connected to the rotation means and rotationally driven, a first interlocking roller 22 driven in contact with the outer peripheral surface of the first driving roller 21, The drawing speed of the tow (t) from the pre-tension unit (20) to the relay tension unit (30) can be determined according to the linear momentum considering the rotation speed and diameter per hour of the first driving roller have.

That is, the drawing speed means a moving length of the tow (t) per unit time during the rotation driving of the pre-tension unit 20, and the rotational speed of the pretension unit 20 is the moving speed of the pre- 1 drive roller 21, as shown in FIG.

The diameter of the first driving roller 21 is set to be less than half the diameter of the second driving roller 31 of the relay tension unit 30 and the third driving roller 41 of the main tension unit 40 And the pulling speed can be precisely controlled so that the tangles t drawn out from the tow supply unit 10 are minimized.

1 and 2, the relay tension unit 30 is disposed in the conveying direction of the tow t from the pretension unit 20, and the pre-tension unit 30 20, the pre-tensioning of the tow (t) is performed in accordance with a preset pre-tension ratio based on the limit tension ratio of the poly (lactic acid) fiber.

The relay tension unit 30 is provided with a pair of rollers 31 and 32 vertically arranged so that the outer periphery of the relay tension unit 30 is in contact with each other and the tow t transferred from the pre- And is disposed between the rollers 31 and 32.

When the rollers 31 and 32 of the relay tension unit 30 are rotated, the tows t disposed between the rollers 31 and 32 can be transported toward the main tension unit 40.

2 to 3, the relay tension unit 30 includes a second driving roller 31 connected to the rotating means and rotationally driven, and a second driving roller 31 driven by the second driving roller 31 in contact with the outer peripheral surface of the second driving roller 31, , And the conveying or drawing speed of the tow (t) can be determined according to the linear momentum of the second driving roller (31).

The fact that the relay tension unit 30 is rotated at an increased speed from the rotational speed of the pretension unit 20 means that the second drive roller 31 has a linear momentum exceeding the first drive roller 21 It is desirable to understand it in meaning. That is, the increased rotation can be obtained by rotating the second drive roller 31 at a higher rotation speed with the same diameter as the first drive roller 21, at the same rotation speed with a larger diameter than the first drive roller 21, And the case where both of the number of revolutions and the number of revolutions are rotated high.

When the relay tension unit 30 is rotated at an increased speed, the pull-out speed of the tow through the relay tension unit 30 is higher than the pull-out speed of the tow through the pre-tension unit 20, The tow (t) can be tensioned according to

At this time, the pulling length of the tow (t) is adjusted according to the magnitude of the drawing speed difference between the relay tension unit 30 and the pretension unit 20, and the pulling length of the tow (t) And the relay tension unit 30 is rotated at an increased speed. That is, the line motion amount of the second driving roller 31 is set so that the pulling length of the tow (t) maintains the drawing speed difference that satisfies the preliminary pulling ratio, and the second driving roller 31 has a fixed diameter The amount of linear motion of the second driving roller 31 can be adjusted.

Herein, the critical tensile ratio of the polylactic acid fiber means the maximum elongation ratio per unit length of the tow, and the preliminary tensile ratio is set to be lower than the critical tensile ratio of the polylactic acid fiber. At this time, the preliminary stretch ratio is preferably set to 40% to 60% from the critical stretch ratio of the polylactic acid fiber, and the tow (t) can be stably stretched without breaking. Specifically, when the preliminary tensile ratio is less than 40%, the performance of the cigarette filter produced due to the shortage of the final tensile ratio may be deteriorated or the subsequent tensile ratio through the main tension portion 40 may be set excessively, If the tensile ratio exceeds 60%, there is a fear that a partial disconnection of the tow (t) may occur.

The main tension unit 40 is disposed in the preliminary tension direction of the tow from the relay tension unit 30 and determines the filtration rate of the filter from the rotational speed of the relay tension unit 30 corresponding to the preliminary tension ratio The tow is rotated at an increased speed according to a predetermined target tension ratio to stretch the tow.

In detail, the main tension part 40 is provided with a pair of rollers 41 and 42 arranged vertically so that the outer periphery of each of the rollers 41 and 42 is in contact with each other, and the toe t transferred from the relay tension part 30, Is disposed between the rollers (41, 42).

When the rollers 41 and 42 of the main tension unit 40 are rotated, the tows t disposed between the rollers 41 and 42 can be transported toward the band unit 50.

The main tension unit 40 includes a third driving roller 41 connected to the rotation unit and rotationally driven, a third interlocking roller 42 driven by the third driving roller 41 in contact with the outer peripheral surface of the third driving roller 41, , And the feeding or drawing speed of the tow (t) can be determined according to the linear momentum of the third driving roller (41).

The fact that the main tension unit 40 is rotated at an increased speed from the rotational speed of the relay tension unit 30 means that the third drive roller 41 has a linear momentum exceeding the second drive roller 31 It is desirable to understand it in meaning. That is, the increased rotation can be obtained by rotating the third drive roller 41 at a higher rotation speed with the same diameter as the second drive roller 31, at the same rotation speed with a larger diameter than the second drive roller 31, And the case where both of the number of revolutions and the number of revolutions are rotated high.

When the main tension unit 40 is rotated at an increased speed, the pulling speed of the tow through the main tension unit 40 is higher than the pulling speed of the tow through the relay tension unit 30. Therefore, The tow (t) can be tensioned according to

At this time, the pulling length of the tow (t) is adjusted according to the magnitude of the drawing speed difference between the main tension unit 40 and the relay tension unit 30, and the pulling length of the tow (t) The main tension unit 40 is preferably rotated at an increased speed. That is, the linear motion amount of the third driving roller 41 is set so that the pulling length of the tow (t) maintains the drawing speed difference that satisfies the target pulling ratio, and the third driving roller 41 has the diameter The amount of linear motion of the third driving roller 41 can be adjusted.

Here, the target tension ratio is set based on the filtration rate of the filter. In detail, the tow (t) is twisted when the tensile force is removed after being pulled in the initial untensioned state, and the ventilation rate and the filtration rate can be adjusted according to the amount of twist formed in the short fiber when the filter is made into a cigarette filter.

At this time, the ventilation rate acts as a variable for determining the suction pressure and taste during smoking, and the filtration rate serves as a parameter for determining the collection / removal performance of the harmful components in the smoke during smoking.

That is, the twist amount is adjusted according to the tensile amount of the tow (t), and the filtration rate and the ventilation rate of the filter are controlled according to the twist amount, so that the twist amount and the twist amount of the tow (t) Can be set.

At this time, the target tension ratio is preferably set to 150 to 300% of the unit length of the untensioned tow (t). Accordingly, the filtration rate and the ventilation rate of the filter manufactured through the tow (t) can be improved.

Specifically, when the target tension ratio is less than 150%, the filtration rate of the filter may be insufficient. When the target tension ratio is more than 300%, a partial disconnection of the tow (t) There is a concern.

The distance between the relay tension portion 30 and the main tension portion 40 can be increased in a state in which the tow t is preliminarily stretched according to the drawing speed difference between the pre-tension portion 20 and the relay tension portion 30, Due to the pulling speed variation, the polylactic acid fiber-based low-elastic tow can be pulled to a wide range without breaking, owing to the progressive pulling of the two stages.

In addition, since low surface energy unique to polylactic acid fibers can be compensated for by increasing the surface area according to a wide range of tensile, it provides a base technology capable of mass production of a filter having high biodegradability while satisfying the filtration rate corresponding to an acetate fiber based filter can do. That is, the filtration rate and decomposition rate of the filter, which can be degraded by low surface energy, are compensated by the large surface area, so that the filtration rate and decomposition rate of the filter made of polylactic acid fiber tow can be improved.

On the other hand, the band portion 50 blows and fines the stretched tow (t) to disperse and align it. Specifically, the band portion 50 includes a banding jet 51 for dispersing compressed air in a stretched tow t and arranging the compressed air in a wide spread state, and a plastic processing portion 52 for supplying a plasticizer to the expanded tow t . Thus, the stretched tow (t) is aligned in a form suitable for subsequent injection molding and can be uniformly calcined in a widely dispersed state.

The tow (t) subjected to the preliminary treatment can be injected into the injection part (70) with the band width reduced through the guide part (60). That is, the tow (t) is arranged in a wide unfolded state so that the entanglement generated during the tensile process is removed through the band portion 50 to facilitate the digestion process, and after the digestion process, (60). ≪ / RTI >

The guide portion 60 is provided with a pair of rollers 61 and 62 arranged vertically so that the outer periphery of the guide portion 60 is in contact with each other. And is conveyed to the side of the injection part 70 while wrapping the lower roller 62. At this time, the upper roller 61 is rotated by the fourth servomotor 63, which is a separate rotating means that is rotated with the rotating means 23, 33, 43 of each of the tension portions 20, The pulling speed of the tow through the guide portion 60 is set to be equal to or lower than the pulling speed of the tow t through the main tension portion 40 .

The injection unit 70 includes a molding die for molding the injected tow t in a sectional area corresponding to the tobacco filter and a pressurizing heating unit for supplying molding heat and molding pressure so that the shape of the formed tow t is maintained. Apparatus, and the like. Accordingly, the tow (t) can be pressurized and injected into the cigarette filter.

At this time, the manufactured cigarette filter is conveyed to the failure detecting device 90 in a packed state through the packaging device 80, and can be transferred to the pick-up drum d via the failure detecting device 90. The tobacco filter is gripped on the pick-up drum d and rotated, and defective products are removed according to the result of the discrimination by the defect detection device 90, and good products can be separated and collected in the final collection box.

3 to 4, the rotating means includes a plurality of servomotors 23, 24 independently connected to the first driving roller 21, the second driving roller 31, and the third driving roller 41, 33 and 43, respectively. That is, the first driving roller 21 is rotationally driven by the first servo motor 23 connected to the driving shaft, and the second driving roller 31 is rotationally driven by the second servo motor 33 connected to the driving shaft. And the third drive roller 41 is rotationally driven by the third servo motor 43 connected to the drive shaft.

Accordingly, the number of revolutions of the driving rollers 21, 31 and 41 can be independently controlled, and the pulling-out speed of the tow through the tensioning parts 20, 30 and 40 can be independently controlled.

In other words, conventionally, the speed deviation of each driving roller connected to independent rotating means can be expanded and controlled to a wide range, unlike the case where each driving roller is controlled to be shifted by being connected to one rotating means by using a pulley gear.

Further, even if the gears or pulleys are not replaced for shifting the driving rollers, the number of revolutions of the servomotors 23, 33, 43 can be easily adjusted so that the pulling speed of the tow through the tensioning portions 20, 30, Can be adjusted.

Accordingly, the shift deviation between the drive rollers 21, 31 and 41 can be controlled to be widened to a wide range so as to correspond to the preliminary extension ratio and the target extension ratio, .

This makes it possible to manufacture general tow-based filters as well as to manufacture polylactic acid fiber tow-based filters that require a wide range of tensile, and it is possible to produce filters with various types of polylactic acid fiber tows having different physical properties depending on the manufacturing process and additives. The productivity and compatibility of the device can be improved.

At this time, the servo motors (23, 33, 43) can be controlled by the logic controller (C). In detail, the programmable logic controller refers to a control device that sequentially calculates a plurality of output values corresponding to a plurality of input values according to an input program and controls an external device according to the calculated output value.

The diameter, the pre-tension ratio, the target tension ratio, and the number of rotations of the first driving roller 21 are input to the logic controller C as input values. At this time, the number of revolutions of the first driving roller 21 is output as an output value for driving the first servo motor 23, and the number of revolutions of the second driving roller 31 and the third The number of revolutions of the driving roller 41 can be calculated and output as an output value for driving the second servo motor 33 and the third servo motor 43. [

That is, the number of revolutions corresponding to the diameter of the second driving roller 31 is calculated on the basis of the line motion amount corresponding to the revolution number and the diameter of the first driving roller 21 and the drawing speed difference of the tow that satisfies the preliminary extension ratio . The number of revolutions corresponding to the diameter of the third driving roller 41 can be calculated based on the calculated linear movement amount of the second driving roller 31 and the drawing speed difference of the tow that satisfies the target tension ratio. At this time, the calculated rotational speeds of the second drive roller 31 and the third drive roller 41 may be output as output values for driving the second servo motor 33 and the third servo motor 43.

The relay tension unit 30 and the main tension unit 40 are rotated by the predetermined tension ratio so that the target tension ratio of the relay tension unit 30 and the relay tension unit 30 is increased, The tension of the tow can be controlled.

That is, if only the preliminary extension ratio and the target extension ratio are input, the plurality of servomotors 23, 33, and 43 can be linked and controlled to perform the pulling process of the tow, so that the usability of the apparatus can be improved.

5 is a partial view illustrating an apparatus for manufacturing a biodegradable cigarette filter according to another embodiment of the present invention. In the other embodiment, the basic configuration except for the pressure friction layers 224, 234, and 244 and the press protrusions 224a, 234a, and 244a is the same as that of the above-described embodiment, so a detailed description of the same configuration will be omitted.

As shown in FIG. 5, the outer peripheral surfaces of the driving rollers 221, 231, and 241 and the interlocking rollers 222, 232, and 242 are preferably provided with pressing friction layers 224, 234, and 244 of elastic material so that the tows can be pressed and bonded.

In detail, the pressing friction layers 224, 234, and 244 may be formed by coating an elastic material such as silicone or rubber along the surfaces of the driving roller and the interlocking roller. When the driving roller and the interlocking roller, which are vertically opposed to each other, Can be formed. As a result, the slippage of the tow (t) between the rollers is reduced to enable precise feeding, and the tow (t) can be accurately tensioned so as to correspond to the drawing speed difference between the tension portions (220, 230, 240).

On the outer circumference of the pressure friction layers 224, 234, 244, pressing protrusions 224a, 234a, 244a having a predetermined first width in the circumferential direction but extending in the axial direction may be formed.

That is, the pressing protrusions 224a, 234a, and 244a are formed in the axial direction from one side of the rim of the pressing friction layer 224, 234, and 244 to the other side of the rim, and have a semicircular shape with a diameter corresponding to the first width It is preferable to stagger so as to form a rectangular cross section having a width corresponding to the first width.

At this time, the pressing protrusions 224a, 234a, and 244a are formed in multiple stages in the circumferential direction along the surfaces of the pressing friction layers 224, 234, and 244, and are spaced apart from each other at intervals corresponding to the first width. That is, the two pressing projections adjacent in the circumferential direction are spaced apart from each other by a first width corresponding to the width of one pressing projection.

As a result, when the drive roller side pressure friction layer and the driven roller side pressure friction layer come into contact with each other, the pressure projection of another pressure friction layer can be inserted and engaged with the space between the pressure projections of the pressure friction layer on one side.

That is, the pressing protrusions of the opposing pressing friction layers form circumferential concave and convex portions, and the pressing protrusions of the one pressing friction layer and the pressing protrusions of the other pressing friction layer forming the concave and convex portions are maintained in a gear- The roller can be rotated.

At this time, the tow (t) can be gripped and transported in zigzag form between the interlocking press projections. Accordingly, the slippage of the tow (t) between the rollers can be minimized, and the tow (t) can be tensioned more accurately so as to correspond to the drawing speed difference between the tension portions (220, 230, 240).

As described above, the present invention is not limited to the above-described embodiments, and variations and modifications may be made by those skilled in the art without departing from the scope of the present invention. And such modifications are within the scope of the present invention.

100, 200: a biodegradable cigarette filter manufacturing apparatus 10:
20: pre-tension unit 30: relay tension unit
40: main tension part 50: band part
60: Guide part 70: Injection part

Claims (5)

A tow supply unit for supplying a tow of poly lactic acid fiber material;
A pre-tension unit provided at one side of the tow supply unit, for drawing and feeding the supplied tow at a predetermined withdrawal speed;
Wherein the pulling speed of the tow is increased by a predetermined preliminary tension ratio based on a limiting pull ratio of the polylactic acid fiber from a rotation speed corresponding to the pulling speed, Relay tension section;
A main tension unit disposed in the preliminary tension direction of the tow from the relay tension unit and rotated at an increased speed according to a predetermined target tension ratio based on a filtration rate of the filter from a rotation speed corresponding to the preliminary extension ratio to pull the tow; And
And an injection part for producing a cigarette filter by pressurizing and injecting the pulled tow to the biodegradable tobacco filter. The method according to claim 1,
Wherein the pretension part, the relay tension part, and the main tension part comprise a driving roller connected to the rotation unit and driven to rotate, and an interlocking roller which is rotated in contact with the outer circumferential surface of the driving roller,
Wherein the rotating means includes a plurality of servo motors independently connected to the driving rollers so that a speed change deviation between the respective driving rollers is controlled so as to be expanded corresponding to the preliminary tension ratio and the target tension ratio. Device. 3. The method of claim 2,
And a pressure friction layer made of an elastic material is provided on the outer circumferential surface of the driving roller and the interlocking roller so that the tow is pressed and bonded,
Wherein the rotation means is configured to rotate the servo motors so that the pre-tension portion and the relay tension portion are varied in rotation in accordance with the pre-tension ratio and the relay tension portion and the main tension portion are varied in accordance with the target tension ratio, And a logic controller for controlling the biodegradable cigarette filter. The method of claim 3,
A pressing projection extending in the axial direction and having a predetermined first width in the circumferential direction is formed on the outer circumference of the pressing friction layer,
Wherein the pressing protrusions are disposed at a distance corresponding to the first width so as to engage with the pressing protrusions of the other pressing friction layers opposed to each other in a multi-step manner along the circumferential direction. The method according to claim 1,
The preliminary tensile ratio is set to 40 to 60% of the preliminary tensile ratio,
Wherein the target tensile ratio is set to 150 to 300% from the unit length of the untensioned tow.

Images