CN113349410A

CN113349410A - Method and device for reproducing tobacco leaves

Info

Publication number: CN113349410A
Application number: CN202110753931.9A
Authority: CN
Inventors: 朱忠元
Original assignee: Yue Yuanfen
Current assignee: Yue Yuanfen
Priority date: 2021-07-04
Filing date: 2021-07-04
Publication date: 2021-09-07
Anticipated expiration: 2041-07-04
Also published as: CN113349410B

Abstract

The invention discloses a method and a device for reproducing tobacco leaves, which are based on a broken leaf sewing-up method for reproducing the tobacco leaves, wherein the broken tobacco leaves in a sheet shape are uniformly and orderly paved on a supporting body to form aggregates by an electrostatic or negative pressure airflow guiding method, then a dry paper-making method is adopted for reproducing the related processes of the tobacco leaves, the gaps between the broken leaves are filled and sewed by using additional fibers, a continuous whole reproduced tobacco leaf substrate is manufactured, and then an extract coating is coated, dried, coiled or sliced and packaged to manufacture a tobacco sheet. The method is simple and easy to implement, the equipment manufacturing cost is low, energy and water are saved in the reconstituted tobacco production process, the environment protection is facilitated, the tobacco sheet manufactured according to the scheme meets or is superior to the standard YC/T16.3-2003, and the area ratio of the original natural tobacco leaves in the tobacco sheet is more than or equal to 70%. Compared with various technical schemes of the reconstituted tobacco disclosed in the prior art, the finished product has the highest similarity with natural tobacco leaves, and has good compatibility with natural tobacco shreds in the cigarette production process.

Description

Method and device for reproducing tobacco leaves

Technical Field

The invention relates to a method and a device for reproducing tobacco leaves, which specifically comprise the following steps: the tobacco shreds in sheet form are drawn by electrostatic or negative pressure airflow and laid on a bearing body in order, then the gaps between the shreds are filled and sewed by additional fibers guided by the airflow, sticky paint is sprayed on the two sides of the shreds in sequence and then the shreds are dried into paper webs, and the reconstituted tobacco is obtained after the quality control treatment. Belongs to the technical field of tobacco sheet production in the cigarette industry.

Background

Before the tobacco leaves in the cigarette industry are purchased and put in storage, the tobacco leaves are subjected to procedures of grading, grading packaging, threshing and redrying and the like, each procedure can generate tobacco powder, broken stems and tobacco leaf fragments, the tobacco leaf fragments with larger diameters are generally mixed into the processed tobacco packets, and the tobacco powder with smaller diameters can be generated in the shredding and the subsequent procedures. According to statistics, in the cigarette processing process, tobacco residues such as tobacco powder, broken stems, tobacco leaf fragments and the like account for 5-7% of the total production amount of the cigarette. The reconstituted tobacco is a sheet or thread-shaped regenerated tobacco product (also called tobacco sheet) which is prepared by carrying out technical treatment and recombination processing on the tobacco powder, broken stems, tobacco fragments and other substances. The reconstituted tobacco is used as a filler of a cigarette product, has the advantages of saving tobacco raw materials, flexibly regulating and controlling the physical and chemical properties of cigarettes and the like, is an important component of a cigarette formula, can partially replace the tobacco, effectively reduces the natural tobacco components in the cigarettes and improves the utilization rate of tobacco resources; the physical properties and chemical components of the cigarette can be adjusted and improved to a certain extent according to the will or requirements of people, and particularly, the full utilization of the tobacco fragments generated in the treatment process of high-quality tobacco leaves is particularly important.

Known methods of reconstituted tobacco include: a roll press process, a thick stock process, a wet papermaking process, a dry papermaking process, and the like, wherein: the roll-pressing method and the thick slurry method are basically eliminated. The disclosed patents related to the wet paper-making process and the dry paper-making process for reproducing tobacco leaves include: the Chinese patent inventions "a production process of a functional paper-making reconstituted tobacco" (application number: 031428029), "a dry paper-making reconstituted tobacco and a production method thereof" (application number: 2008100301465), "a tobacco sheet and a manufacturing method and a manufacturing system thereof" (application number: 008084882) "applied in China by Nippon tobacco industries, Inc., and" a dry manufacturing method of homogenized tobacco "and an obtained product thereof" (application number: 85105001) and the like.

The wet paper-making method is the mainstream in the current reconstituted tobacco industry, and the production process comprises the following steps: the tobacco residues such as tobacco powder, broken stems, broken pieces and the like are steamed and ground into wet fiber pulp by a wet method, and then the wet fiber pulp is manufactured, coated and dried into tobacco sheets by a long mesh paper machine. The advantages are that: the finished tobacco sheet has high similarity with natural tobacco leaves in appearance and internal quality, and has good compatibility with natural tobacco shreds, and the defects are as follows: the tobacco fragrance loss is serious, the water and electricity consumption in the production process is large, the production efficiency is low, and the like, particularly, the generated waste water can not be treated almost, and even if the waste water can be effectively treated into the reclaimed water, the treatment cost of the reclaimed water accounts for the proportion of the manufacturing cost of the finished product. The dry paper-making method is an emerging research in recent years, and the processes mainly comprise two types: extracting raw materials such as broken tobacco leaves and the like, separating out extract liquor and extract slag, pulping and drying the extract slag to prepare extract slag dry fibers, mixing and adding wood pulp fibers on a dry method paper machine to carry out air flow forming to obtain a reconstituted tobacco substrate, spraying or dip-coating an adhesive and an extract prepared from the extract liquor on the substrate, drying and slitting to prepare a tobacco sheet; the disadvantages are as follows: the weight and physical shape of the granular extraction slag slurry powder and the external fiber are different, the state difference appearing in the air is too large, and the problems of extremely uneven distribution of the extraction slag and the external fiber and more extraction slag slurry powder loss appear on the forming mesh surface in the actual forming process; secondly, grinding the tobacco powder and the tobacco powder into powder of about 100 meshes, adding chitosan, adhesive, water and the like to prepare coating, spraying the coating on a wood pulp fiber substrate formed by airflow of a dry paper machine, drying and cutting to prepare the tobacco sheet. The dry papermaking method has the advantages that: the manufacturing process is relatively simple, and the pollution degree to the environment is low; the disadvantages are as follows: the controllability on the appearance and the internal quality of the product in the processing process is poor, the finished product sheet even has a layering phenomenon, the proportion of non-tobacco components in the tobacco sheet is large, a special tobacco cutter different from a natural tobacco cutter is required to be added in a cigarette factory, the cut tobacco forming rate after cutting is low, and particularly the compatibility with natural cut tobacco is poor.

The flocking step in the Chinese invention 'a method for manufacturing non-combustion type cigarette based on flocking technology' (application number: 202010305575. X) is to transplant filiform, fibrous or granular tobacco to the surface of cigarette paper by using electrostatic flocking technology, and then connect cigarette rolling process to obtain the non-combustion type cigarette. The known electrostatic flocking utilizes the physical characteristics that like charges repel each other and opposite charges attract each other to make the villus have negative charges, and the villus is attracted by plants by the different potentials when an object to be flocked is placed under the condition of zero potential or grounding, is accelerated to fly to the object to be flocked in a vertical shape and is adhered to the surface of the object in the vertical shape.

Obviously, the prior art relating to the cigarette industry or reconstituted tobacco or flocking technology does not have the following technical scheme: the method comprises the steps of uniformly and orderly spreading the flaky tobacco powder or tobacco leaf fragments in a single layer and adsorbing the tobacco powder or the tobacco leaf fragments on a bearing body, refilling and sewing gaps among the tobacco powder or the tobacco leaf fragments to form a substrate taking the tobacco powder or the tobacco leaf fragments as a main body, and then coating, drying, reeling or slicing the substrate. The beneficial effects of the innovative idea are that: the geometric advantages of the natural leaves can be utilized to the maximum extent to manufacture tobacco flakes, the tobacco flakes are not required to be smashed into paste or ground into pulp to manufacture tobacco sheets, the fragrance of the tobacco leaves is hardly lost, and the finished product has good compatibility with the natural tobacco leaves.

Disclosure of Invention

The invention provides a method and a device for reproducing tobacco leaves, which aims at solving the problems in the prior art, and the method and the device are characterized in that flaky tobacco powder or tobacco leaf fragments are uniformly and orderly paved on a bearing body by an electrostatic or negative pressure airflow guiding method to form aggregate, then the related processes and equipment of the tobacco leaves reproduced by the disclosed dry paper-making method are used for reference, gaps among the tobacco powder or the tobacco leaf fragments are filled and sewed by using external fibers to form a continuous whole reproduced tobacco leaf substrate, and then the whole reproduced tobacco leaf substrate is coated with viscous paint, dried, coiled or sliced and packaged to be manufactured into a tobacco sheet. The method is simple and easy to implement, the equipment manufacturing cost is low, and the reconstituted tobacco is energy-saving and water-saving in the processing and production processes and is beneficial to environmental protection. The tobacco sheet manufactured according to the technical scheme meets or is superior to the standard YC/T16.3-2003, and the area ratio of the original natural tobacco leaves in the tobacco sheet is more than or equal to 70 percent. Compared with various technical schemes of the reconstituted tobacco disclosed in the prior art, the finished product has the highest similarity with natural tobacco leaves, and has good compatibility with natural tobacco shreds in the cigarette production process.

In order to achieve the purpose, the invention adopts the following technical scheme:

a method for reproducing tobacco leaves is a broken-leaf-based sewing-up method tobacco leaf reproducing process, and comprises the following steps: aggregate preparation process, substrate preparation process and the working procedures of pressing, coating, drying, reeling or slicing; the preparation process of the aggregate comprises the following steps: the crushed leaves screened out according to the set mesh size are sequentially and uniformly paved on a movable bearing body in an orderly manner by a suction and transfer method to form a layer of aggregate which is adsorbed on the bearing body and is spliced by the crushed leaves; the substrate preparation process is to add additional fibers into gaps among the crushed tobacco leaves by using an airflow sedimentation method, fill and sew the gaps in the aggregate, and prepare the whole reconstituted tobacco substrate; then, the reconstituted tobacco base sheet is made into a rolled or flaky tobacco sheet by the existing dry paper-making reconstituted tobacco equipment through the processes of compacting, coating, drying, reeling or slicing.

The supporting body is a flat annular mesh belt, a vacuum box connected with a negative pressure fan is arranged below the annular mesh belt, and the annular mesh belt is used for adsorbing and driving the aggregate to longitudinally advance at a constant speed and transfer to the subsequent process.

Further, the crushed leaf suction method comprises the following steps: one or the combination of two of the electrostatic extraction and transfer process and the negative pressure extraction and transfer process:

the electrostatic pick-up and transfer process comprises: the setting is according to many removal polar needle and the roller and the stator groove of discharging of setting for size range in order, remove the polar needle and be used for leading in proper order in the electrostatic field and get the broken leaf to take the broken leaf to remove to the one side of discharging the roller, let the broken leaf drop to the stator groove after eliminating the electric charge on the broken leaf again, the broken leaf in the stator groove receives gravity and negative pressure air current effect, landing and tiling in proper order extremely on the annular net area, form the aggregate.

The negative pressure extraction and transfer process comprises the following steps: the setting is according to many hollow removal needles and stator roller and the stator groove of setting for size range in order, the front end of hollow removal needle is the needle point, and the end of hollow removal needle can be linked together with negative pressure air supply or atmosphere, and when the end of hollow removal needle was put through with negative pressure air supply, the broken leaf that a slice lies in hollow removal needle below was drawn on the needle point of each hollow removal needle to adsorb the broken leaf antedisplacement, work as when the broken leaf removed stator roller top, the end of hollow removal needle communicates with each other with the atmosphere, and the negative pressure of hollow removal needle point department is eliminated, and the broken leaf drops on the stator groove, and the broken leaf in the stator groove receives gravity and the negative pressure air current effect of annular guipure below, and landing and tiling in proper order form the aggregate on the annular guipure.

Furthermore, the area of the broken leaves in the aggregate can be more than or equal to 70 percent by reasonably setting the arrangement density and the arrangement mode of the movable polar needles or the hollow movable needles and the moving speed of the movable polar needles or the hollow movable needles.

Further, the crushed leaves comprise: tobacco dust and/or tobacco fragments in the form of pieces, and setting: the crushed leaves are sheet-shaped objects with the maximum value of the overall dimension of 0.5-3.5 mm; but in the process of forming the aggregate, the difference of the external dimensions of each crushed leaf for drawing is less than or equal to 1.5 mm; that is, the values of the physical dimension interval of each crushed leaf are respectively: 0.5-2.0 mm, 1.0-2.5 mm, 1.5-3.0 mm, 2.0-3.5 mm. The beneficial effects are as follows: the method is beneficial to setting production process parameters, evenly guiding and fetching the broken leaves, improving the splicing effect among the broken leaves, realizing the maximization of the area ratio of the broken leaves and achieving the maximization of the area ratio of the original tobacco leaves in the finished tobacco sheets.

Further, setting: the diameter of the mesh or the length of the diagonal line on the annular mesh belt is less than or equal to 0.3 mm; the annular net belt is always grounded and has zero potential in work.

The invention also discloses a reconstituted tobacco production line based on the electrostatic extraction process, which comprises the following steps: broken leaf screening and conveying device, external fiber fluffing and metering conveyor, electrostatic device, broken leaf spreader, fiber spreader, compactor, coating and drying device, and coiling or slicing device.

The additional fiber defibering and metering conveyor comprises: the two-stage fiber fluffer, the storage tank and the fiber metering conveyor exist in the market.

The fiber spreading device, the pressing device, the coating and drying device and the reeling or slicing device adopt related equipment required by the existing dry-method paper making or dry-method reconstituted tobacco, wherein the fiber spreading device is at least one group of drum sieve type dry-method airflow forming heads.

The broken leaf screening and conveying device comprises: a screening machine and a feeding bin; the screening machine is an existing airflow flotation machine and is used for screening crushed leaves with the external dimension of a set interval value from tobacco residues mixed with tobacco powder, crushed stems and tobacco fragments and storing the selected crushed leaves into a feeding bin.

The electrostatic device includes: the electrostatic generator and the electrostatic field leading device are used for forming a high-voltage electrostatic field; the electrostatic device is used for orderly drawing and taking the crushed leaves by moving the pole needle and transferring the crushed leaves to one side of the discharging roller under the action of an electrostatic field.

The electrostatic field connecting and guiding device comprises: a positive plate and a negative plate.

The broken leaf spreading device comprises: the device comprises a feeder, a rotary drum, a transition plate, a discharge roller, a guide vane groove, a blowing box and an air suction box.

The feeder is used for receiving and sending out the broken leaves that come from the feed bin, includes from last to setting gradually down: the device comprises a hopper, a spiral material distributing device, a material outlet and a feeding conveyor belt; the spiral distributing device is used for uniformly distributing the crushed leaves on the feeding conveyor belt.

The rotary drum is located the top of pay-off conveyer belt, includes: two guide rollers, chain wheels and needle plates; the needle plates are made of conductive materials, the needle plates are in a strip shape, the side parts of the needle plates are hinged with each other, the hinges at the hinged parts are mutually insulated, a closed flat long circular needle plate belt surrounding between the two guide rollers is formed, and the needle plates in the needle plate belt are mutually insulated; the sprocket links firmly two ends at the deflector roll, the both ends of faller link firmly the chain link by insulating material preparation, the chain link meshes with the sprocket, works as the drive when the deflector roll is rotatory, the sprocket drives promptly the faller area rotary motion between the deflector roll.

One end of the single needle plate is provided with a conductive brush which is used for being in sliding contact with the electrostatic field leading device or the grounding end.

The discharging roller is positioned at the right lower part of the rotary drum, the transition plate is positioned between the feeding conveying belt and the discharging roller, the guide vane groove is positioned below the discharging roller and above the annular mesh belt, the blowing box is positioned at the left upper part in the rotary drum, and the air suction box is positioned at the right lower part in the rotary drum.

The needle plate is provided with a plurality of through holes according to a set size, and each through hole is fixedly connected with a movable polar needle which is distributed outwards; every removes utmost point needle and is used for drawing a slice in the electrostatic field and is located the garrulous leaf on the pay-off conveyer belt of removal utmost point needle below to when taking the garrulous leaf to remove to and discharging the roller intersection, garrulous leaf and the roller contact that discharges, remove utmost point needle and garrulous leaf and lose static simultaneously, later garrulous leaf releases and drops to the stator guide slot from removing the utmost point needle in proper order, and the garrulous leaf in the stator guide slot receives gravity and negative pressure air current effect, and landing is tiled on annular mesh area in proper order, forms the aggregate.

The movable pole needle is internally provided with a hollow conductive needle tube, the periphery of the conductive needle tube is coated with an insulating layer, only the needle point part of the conductive needle tube is exposed, and the root part of the conductive needle tube is fixedly connected with the needle plate, so that the conductive needle tubes on a single needle plate are electrically connected in parallel, and the conductive brush at one end of the needle plate can be in sliding contact with the positive plate in the electrostatic field leading device or in sliding contact with the grounding end, thereby realizing the electrostatic or grounding of the needle point part of the conductive needle tube.

The transition plate is a flat plate, and the length of the transition plate is equal to the width of the needle plate strip; in operation, the transition plate and the feeding conveyor belt are both communicated with a negative plate in the electrostatic field leading device.

Annular comb teeth which are uniformly distributed along the axial direction are machined on the outer circle of the discharge roller; during operation, when the movable pole needle below the rotary drum rotates from left to right, the discharge roller rotates clockwise, and when the movable pole needle moves to the position near the discharge roller, the needle point part of the conductive needle tube is cut into the tooth gaps of the annular comb teeth, but the movable pole needle is not in contact with the annular comb teeth.

In the work, when and only when the movable pole needle below the rotary drum moves to the position corresponding to the feeding conveyor belt and the transition plate, the needle plate at the position corresponding to the position is in sliding contact with the positive plate through the conductive brush, the movable pole needle is charged with static electricity to form an electrostatic field which can lead the crushed leaves to the needle point of the conductive needle tube and transfer the crushed leaves to the discharge roller, and other movable pole needles except the position corresponding to the movable pole needle are grounded to be zero potential.

The upper part of the left side of the guide vane groove is provided with a slot which is in sliding contact with the tooth surface of the annular comb teeth of the discharge roller, the right side of the guide vane groove is provided with a slideway corresponding to the tooth seam of the annular comb teeth of the discharge roller, and an included angle between the slideway and the mesh surface of the annular mesh belt is an obtuse angle; the slideway is used for receiving crushed leaves falling from the discharging roller, and the crushed leaves sequentially slide and are tiled on the annular net belt under the action of gravity and negative pressure airflow.

The air blowing box is a positive pressure air box, and the air outlet surface of the air blowing box is in sliding contact with the inner side surface of the needle plate belt; the air suction box is a negative pressure air box, and an air inlet surface of the air suction box is in sliding contact with the inner side surface of the needle plate belt; the blowing box is used for cleaning the broken powder at the needle point of the conductive needle tube, and the air suction box is used for adsorbing and holding the fragments which are attracted and taken on the needle point of the conductive needle tube by means of static electricity.

Be provided with along horizontal evenly distributed's rectangular form air outlet on the air-out face of case of blowing, the width of air outlet is less than remove the external diameter of utmost point needle, and set for: the distance between the air outlets is less than or equal to one half of the longitudinal distance of the movable pole needles.

Be provided with on the air inlet face of case that induced drafts along horizontal evenly distributed's rectangular form air intake, the width of air intake is less than remove the external diameter of utmost point needle, and set for: the distance between the air inlets is less than or equal to one half of the longitudinal distance of the movable pole needles.

Setting: the state of the air suction box and the transition plate in the working process is one of the following three states:

when the air suction box sucks air in a full-pressure state, the transition plate does not hold static electricity;

when the transition plate is charged with static electricity, the air suction box does not suck air;

the transition plate is charged with static electricity, and the air suction box is lower than the full-pressure state for air suction.

Preferably, the broken leaf spreading devices are provided with at least two groups, the broken leaves entering each group of broken leaf spreading devices are distributed in equal amount through the arranged broken leaf distributors, the width of each group of broken leaf spreading devices is equal to that of the annular mesh belt, and each group of broken leaf spreading devices are sequentially arranged above the annular mesh belt along the advancing longitudinal direction of the annular mesh belt and are ensured from the geometric position: the mapping points of the movable polar needles of each group of the broken leaf spreading devices mapped on the annular mesh belt are arranged in an equidistant and staggered mode, so that the broken leaf surfaces spread on the annular mesh belt are not overlapped with each other, and the edge distance between the broken leaves is shortest.

Setting: the adjusting method for realizing that the crushed leaf surfaces spread on the annular mesh belt are not overlapped with each other and the edge distance between the crushed leaves is shortest in work comprises but is not limited to the following steps:

the number of the broken leaf spreading devices is set, and the relative installation positions of the broken leaf spreading devices can be finely adjusted by mm;

set up the interval between the removal utmost point needle on each broken leaf spreading device, include:

the transverse distance between the moving pole needles is equal to the tooth pitch on the discharge roller and the slide way distance on the guide vane groove respectively;

the set values of the longitudinal and transverse distances between the movable polar needles are more than or equal to two times of the upper limit size in the broken leaf size interval value; to adapt to the crushed leaves with different size interval values;

an included angle between a slideway on the guide vane groove and the net surface of the annular net belt is set;

adjusting the electric field intensity of an electrostatic field and the geometric distance between electrodes;

comprehensive regulation: the spiral material distributing device, the feeding conveyor belt, the moving pole needles, the moving speed of the annular mesh belt and the rotating speed of the discharging roller; the speed or rotational speed adjustment modes comprise: AC frequency conversion or DC servo speed regulation.

Adjusting the water content of the crushed leaves;

the air quantity and the air pressure value of the air blowing box and the air suction box are adjusted by adjusting the rotating speed of the fan.

The vacuum box is arranged below the annular net belt and vertically corresponds to each group of the broken leaf spreading devices, the vacuum box is used for adsorbing and positioning broken leaves falling in the sliding grooves on the annular net belt, the vacuum box is connected with an external negative pressure fan, and the rotating speed of each negative pressure fan in work is adjustable.

The dry process air forming head in the fiber spreader comprises: a cylindrical screen; the cylindrical screen is positioned at the upper part of the dry airflow forming head, a scattering roller is arranged in the cylindrical screen, the annular mesh belt is positioned below the cylindrical screen, and a vacuum box connected with an external negative pressure fan is arranged at the lower part of the annular mesh belt corresponding to the cylindrical screen; the cylinder screen receives the additional fiber from the additional fiber fluffing and metering conveyer.

The annular mesh belt is wound outside each vacuum box; when a layer of broken leaves is fully paved on the annular mesh belt and enters the lower part of the cylindrical screen, the external fibers flow out of the screen holes of the cylindrical screen in a jet shape, are guided by the airflow of the corresponding vacuum box below the dry airflow forming head and are stored in gaps among the broken leaves, and finally the broken leaves are interwoven into a whole continuous reconstituted tobacco substrate; because the air permeability of the gaps among the crushed leaves is far higher than that of the crushed leaf surfaces, the storage amount of the added fibers on the crushed leaf surfaces is far less than that among the gaps of the crushed leaves.

The compactor is characterized in that the compactor is composed of two upper rollers and two lower rollers which are vertically arranged, the upper rollers are smooth rollers, the lower rollers are rubber covered rollers, and the lower rollers are driving rollers with adjustable rotating speeds.

The coating and drying device comprises: upper spraying, a No. 1 drying box, lower spraying and a No. 2 drying box; the drying mode is set as hot air penetration drying; and in the coating and drying processes, the reconstituted tobacco substrate is borne on the arranged net belt.

Further, the drying mode after coating comprises: hot air penetrating drying and infrared drying; the drying device after coating includes: the reconstituted tobacco substrate is carried on a drying net belt and is dried in a penetrating manner by hot air; or the reconstituted tobacco substrate is suspended between heating sources through hot air penetration drying in an air floatation mode.

The invention also discloses a reconstituted tobacco production line based on the negative pressure extraction process, which comprises the following steps: broken leaves sieving and conveying device, external fiber fluffing and metering conveyor, leaves distributing device, fiber spreading device, pressing device, coating and drying device, and coiling or slicing device.

The leaf distributing device comprises: the device comprises a feeder, a rotary drum, a guide vane roller, a guide vane groove, a positive pressure box and a negative pressure box.

The feeder is used for receiving and sending out the broken leaves that come from the feed bin, includes from last to setting gradually down: the device comprises a hopper, a spiral material distributing device, a material outlet and a feeding conveyor belt; the spiral feed divider is used for distributing the broken leaves on the feeding conveyer belt evenly.

The rotary drum is located the top of pay-off conveyer belt, includes: two guide rollers, chain wheels and needle plates; the needle plates are in a long strip shape, and the side parts of the needle plates are hinged with each other to form a closed flat long circular needle plate belt which is encircled between the two guide rollers; the sprocket links firmly two ends at the deflector roll, the both ends of faller have linked firmly the chain link, the chain link meshes with the sprocket, works as the drive when the deflector roll is rotatory, the sprocket drives promptly the faller area rotary motion between two deflector rolls.

The guide vane roller is positioned on the right lower side of the rotary drum, and the guide vane groove is positioned on the left lower side of the guide vane roller and above the annular mesh belt.

The needle plate is provided with a plurality of through holes according to a set size, hollow moving needles which are distributed outwards are fixedly connected in the through holes, and the inner diameter of a needle tube at the needle point of each hollow moving needle is smaller than the diameter of the through hole in the needle plate; each hollow moving needle is used for guiding and taking a crushed blade on a feeding conveying belt right below, and when the crushed blade is driven to move to a joint with the guide vane roller, negative pressure is lost in the hollow moving needle, the crushed blade is released to the guide vane groove through the guide vane roller in sequence, and the crushed blade in the guide vane groove slides down and is tiled on the annular mesh belt in sequence under the action of gravity and negative pressure airflow to form aggregate.

The positive pressure box is positioned at the upper left part in the rotary drum, the air outlet surface of the positive pressure box is in sliding contact with the inner side surface of the needle plate strip, and the positive pressure box is used for cleaning the broken powder at the needle point of the movable pole needle; the negative pressure box is positioned between two guide rollers below the positive pressure box in the rotary drum, and the air inlet surface of the negative pressure box is in sliding contact with the inner side surface of the needle plate strip; the negative pressure box is used for sucking and holding the crushed leaves at the needle point of the hollow moving needle.

Be provided with along horizontal evenly distributed's rectangular form air outlet on the air-out face of positive pressure case, the width of air outlet is less than the external diameter of hollow removal needle, and set for: the distance between the air outlets is less than or equal to one half of the longitudinal distance of the hollow moving needle.

Be provided with along horizontal evenly distributed's rectangular form air intake on the air inlet face of negative pressure tank, the width of air intake is less than the external diameter of hollow removal needle, and set for: the distance between the air inlets is less than or equal to one half of the longitudinal distance of the hollow moving needle.

The guide vane roller and the discharge roller have the same structure, and annular comb teeth which are uniformly distributed along the axial direction are machined on the outer circle of the guide vane roller; in the work, the guide vane roller and the hollow moving needle rotate in opposite directions, but the hollow moving needle is not contacted with the annular comb teeth; when the hollow moving needle moves to the position near the guide vane roller, the needle point at the front end of the hollow moving needle carries crushed leaves to cut into the tooth gaps of the annular comb teeth, and the crushed leaves fall onto the guide vane groove due to pressure loss.

The upper part of the right side of the guide vane groove is provided with a slot which is in sliding contact with the tooth surface of the annular comb teeth of the guide vane roller, the left side of the guide vane groove is provided with a slide way which corresponds to the tooth seam of the annular comb teeth of the guide vane roller, and an included angle between the slide way and the mesh surface of the annular mesh belt is an obtuse angle; the slideway is used for receiving crushed leaves falling from the guide vane roller, and the crushed leaves sequentially slide and are flatly paved on the annular net belt under the action of gravity and negative pressure airflow.

A partition plate is arranged between the lower part of the feeding conveyor belt and the upper part of the annular mesh belt and is used for receiving scattered crushed leaves above the feeding conveyor belt and transferring the scattered crushed leaves to an externally arranged crushed leaf recovery device in a vibration mode for recycling.

Preferably, the leaf distributor is provided with at least two groups, the width of the leaf distributor is equal to that of the annular mesh belt, and each group of leaf distributors are sequentially arranged above the annular mesh belt along the longitudinal direction of the advancing annular mesh belt and ensure that: the mapping points of the hollow moving needles of each group of leaf distributors mapped on the annular mesh belt are arranged in an equidistant and staggered mode, so that the leaf surfaces of the crushed leaves spread on the annular mesh belt are not overlapped with each other, and the edge distance between the crushed leaves is shortest.

setting the number of the leaf distributing devices, wherein the installation positions of the leaf distributing devices can be finely adjusted in mm level;

set up the interval between the hollow moving needle on each leaf distributor, include: the transverse spacing between the hollow moving needles is equal to the tooth pitch on the guide vane roller and the spacing between the slideways on the guide vane grooves respectively; the set values of the longitudinal and transverse distances between the hollow moving needles are more than or equal to two times of the upper limit size in the crushed leaf size interval value so as to adapt to crushed leaves with different size interval values;

comprehensive regulation: the spiral material distributing device, the feeding conveyor belt, the moving pole needles, the moving speed of the annular mesh belt and the rotating speed of the guide vane roller; the speed or rotational speed adjustment modes comprise: AC frequency conversion or DC servo speed regulation;

adjusting the water content of the crushed leaves;

the air quantity and the air pressure value of the negative pressure box are adjusted by adjusting the rotating speed of the fan.

And the vacuum box is positioned below the annular mesh belt and vertically corresponds to each group of leaf distributing devices, is used for adsorbing and positioning broken leaves falling in the sliding groove on the annular mesh belt, is connected with an external negative pressure fan, and has adjustable rotating speed of each negative pressure fan in work.

Further, the coating mode includes: two-sided spraying or once two-sided dip-coating in proper order, the stoving mode after the coating includes: hot air penetrating drying and infrared drying; the drying device after coating includes: the reconstituted tobacco substrate is carried on a drying net belt and is dried in a penetrating manner by hot air; or the reconstituted tobacco substrate is suspended between heating sources through hot air penetration drying in an air floatation mode.

Preferably, the additional fibers of the present invention include, but are not limited to: one or a mixture of at least two of all-wood fluff pulp fibers, hemp pulp fibers or tobacco stem fibers.

Further, in the coating apparatus of the present invention, the components of the coating material include, but are not limited to: the coating is sprayed in the prior dry method reconstituted tobacco process, or dipped in the wet paper-making reconstituted tobacco, or chitosan-containing coating with good compatibility with natural tobacco shreds in the cigarette production line is directly prepared.

The invention has the beneficial effects that:

the method comprises the steps of crushing and then processing the tobacco residues in the conventional wet paper-making method reconstituted tobacco, dry method reconstituted tobacco, rolling method or thick pulp method. The invention selects the tobacco broken leaves with set specification only by a physical method, uniformly and orderly spreads the selected broken leaves on an annular net belt by an electrostatic extraction or negative wind pressure extraction mode, then uses a dry airflow forming device to interweave and store the added fibers in gaps among the broken leaves, and finally interweaves the broken leaves into a whole continuous reconstituted tobacco substrate. Because the air permeability of the gaps among the crushed leaves is far higher than that of the crushed leaf surfaces, the storage amount of the added fibers on the crushed leaf surfaces is far less than that among the gaps of the crushed leaves.

Compared with the prior various reconstituted tobacco processes, the process is simple and easy to implement, requires less equipment, requires low energy consumption per unit yield, has less pollution emission in the production process and is easy to treat or recover.

Experiments show that in the technical scheme of the invention, the ratio of the gap area between the crushed tobacco leaves to the area of the reconstituted tobacco leaf substrate is less than or equal to 25% by optimally selecting the electrostatic field voltage, the structural size, the installation position, the operation parameters and the like of the devices such as the rotary drum, the slide way and the like, so that the proportion of the original natural tobacco leaves in the prepared tobacco sheet finished product is higher than that of any conventional reconstituted tobacco leaf method or device.

Drawings

Fig. 1 is a schematic block diagram of a reconstituted tobacco production line based on an electrostatic extraction process according to one embodiment of the invention.

FIG. 2 is an enlarged view of the broken leaf spreading device No. 1-3 and the fiber spreading device in FIG. 1.

FIG. 3 is a schematic diagram showing the distribution of aggregates partially laid on an endless mesh belt, and the blank between various irregular-shaped crushed leaves in the diagram is a region to be filled and sewed with additional fibers and coated with a coating in a subsequent process.

Fig. 4 is a schematic three-dimensional structure diagram of a broken leaf spreading device for picking broken leaves by adopting an electrostatic method, wherein only three moving polar needles at the left, the middle and the right are shown to be assembled on a needle plate forming a rotary drum for the sake of clarity.

Fig. 5 is an enlarged view of a portion a in fig. 4.

Fig. 6 is a front view of fig. 4.

Fig. 7 is a right side view of fig. 6.

Fig. 8 is an enlarged view of fig. 7 at B.

Fig. 9 is a front view of a structure of a tobacco distributor in a "reconstituted tobacco production line based on a negative pressure extraction process" according to a second embodiment of the present invention.

Fig. 10 is a top view of fig. 9, showing only three hollow moving needles on the left, center and right, mounted on the needle plates constituting the drum for clarity of illustration.

FIG. 11 is an external view of a negative pressure bellows according to the first embodiment.

FIG. 12 is a schematic view and a partial enlarged view of the air inlet surface of the negative pressure bellows of FIG. 11.

FIG. 13 is a schematic view of the structure of the drum after all the moving pole needles or hollow moving needles are installed.

Fig. 14 is a schematic view and a partial enlarged view of the drum structure of fig. 13 showing only a single needle plate.

Fig. 15 is a schematic view and a partial enlarged view of the structure of the discharge roller or the guide vane roller according to the first or second embodiment.

Fig. 16 is a schematic structural diagram of an appearance of a guide vane groove.

Fig. 17 is an enlarged view at C in fig. 16.

FIG. 18 is a schematic view and a partial enlarged view of a single needle plate structure equipped with a moving pole needle or a hollow moving needle.

Fig. 19 is a side view of fig. 18.

Fig. 20 is a schematic view of the internal structure of fig. 19 taken along the line E-E.

FIG. 21 is a schematic view of a single reconstituted tobacco leaf after being cut into pieces by the production line according to one or both embodiments of the invention. Compared with the figure 3, the blank between the aggregates is filled with the additional fiber and is coated with the coating.

Description of the reference symbols in the drawings:

in fig. 1 and 2: 1-annular mesh belt, 2-negative pressure vacuum box, 3-broken leaf distributor, 4-broken leaf spreader, 5-dry airflow forming head, 6-external fiber fluffing and metering conveying device, 7-fiber distributor, 8-finished reconstituted tobacco; the No. 1F, the No. 2F, the No. 3F and the No. 4F are respectively negative pressure fans, and the rotating speed of each negative pressure fan is adjustable.

In fig. 4-8, 10 and 11, 11-hopper, 12-spiral material distributor, 13-feeding conveyor belt, 14-conveyor belt guide roller, 15-guide roller, 16-chain wheel, 17-rotary drum, 18-blowing box, 19-suction box, 20-transition plate, 21-discharge roller, 22-guide vane groove, 23-needle plate and 24-moving pole needle.

In fig. 9, 11-hopper, 13-feeding conveyor, 16-sprocket, 17-drum, 18-blow box, 19.1-negative pressure box, 20.1-baffle, 21.1-guide vane roller, 22-guide vane groove, 23-needle plate.

In fig. 12, 29-inlet, and e shows the longitudinal center distance between two inlets.

In fig. 14, 25-chain links, L in the figure indicates the path of movement of the needle board.

In fig. 15, d represents the pitch between the annular comb teeth on the discharge roller, and h represents the tooth height of the annular comb teeth.

In fig. 17, 27-slide and 28-slot, and d indicates the distance between two slides.

In fig. 18-20, 23-needle plate, 24-moving pole piece, 24.1-conductive needle tube, 24.2-insulating layer, 25-link, 26-hinge, d in fig. 19 represents the transverse spacing between two moving pole pieces, which is equal to the tooth pitch d in fig. 15 and the slideway pitch d in fig. 17; in FIG. 20, f represents the longitudinal spacing between two moving pole needles on the needle board, and the value of f is more than or equal to twice the value of e in FIG. 12.

Detailed Description

Embodiments of the invention will be further described with reference to the accompanying drawings, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below are exemplary and are intended to be illustrative, but not limiting, of the present invention, and any modifications, equivalents, or improvements made within the spirit and principle of the present invention, which are not described in detail in the technical solutions below, are known in the art, and are intended to be included within the scope of the claims of the present invention.

Referring to the attached

drawings

1 and 2, the method for reproducing the tobacco leaves is characterized in that the crushed leaves screened according to the set mesh size are sequentially and uniformly laid on a movable bearing body in a flat mode through a suction and transfer method to form a layer of aggregate which is adsorbed on the bearing body and is spliced by the crushed leaves and is shown in the figure 3. And then utilizing the existing equipment in the reconstituted tobacco by a dry paper-making method, settling air, adding fibers into gaps among aggregates, filling and sewing the gaps among the aggregates to prepare the whole reconstituted tobacco substrate, and then preparing the sheet tobacco sheet which is in a roll shape or shown in figure 21 through the processes of coating, drying, reeling or slicing.

The supporting body is a tiled annular mesh belt 1, a vacuum box connected with an exhaust fan is arranged below the annular mesh belt 1, and the annular mesh belt 1 is used for adsorbing and driving the aggregate to longitudinally advance to the subsequent process at a constant speed.

The method for sucking and transferring the crushed leaves comprises the following steps: one or the combination of the electrostatic extraction and transfer process and the negative pressure extraction and transfer process.

The electrostatic pick-up and transfer process comprises: the setting is according to many removal utmost point needles 24 and the roller 21 and the stator slot 22 of discharging of setting for size permutation in order, remove utmost point needle 24 and be used for drawing in proper order in the electrostatic field garrulous leaf to take garrulous leaf to remove to the one side of discharging roller 21, eliminate the electric charge on the garrulous leaf again, let garrulous leaf drop to stator slot 22 on, garrulous leaf in the stator slot 22 receives gravity and negative pressure air current effect, and the landing is tiled in proper order on the annular mesh belt 1, forms the aggregate.

The negative pressure extraction and transfer process comprises the following steps: the setting is according to many hollow mobile needles and stator roller and the stator groove of setting for size orderly arrangement, the front end of hollow mobile needle is the needle point, and the end of hollow mobile needle can be linked together with negative pressure air supply or atmosphere, and when the end of hollow mobile needle was put through with negative pressure air supply, the broken leaf that a slice was located hollow mobile needle below was drawn on the needle point of each hollow mobile needle, and is adsorbed the broken leaf antedisplacement, when the broken leaf removed to stator roller top, the end of hollow mobile needle communicated with each other with the atmosphere, and the negative pressure of hollow mobile needle point department is eliminated, and the broken leaf drops on the stator groove, and the broken leaf in the stator groove receives gravity and the negative pressure effect of annular guipure below, and landing is in proper order on the annular guipure, forms the aggregate.

By adopting the technical scheme of the invention, the area of the broken leaves in the aggregate can be more than or equal to 70 percent by reasonably setting the arrangement density and the arrangement mode of the movable polar needles or the hollow movable needles and the moving speed of the movable polar needles or the hollow movable needles.

The crushed leaves comprise: tobacco dust and/or tobacco fragments in the form of pieces, and setting: the crushed leaves are sheet-shaped objects with the maximum value of the overall dimension of 0.5-3.5 mm; but in the process of forming the aggregate, the difference of the external dimensions of each crushed leaf for drawing is less than or equal to 1.5 mm; that is, the values of the physical dimension interval of each crushed leaf are respectively: 0.5-2.0 mm, 1.0-2.5 mm, 1.5-3.0 mm, 2.0-3.5 mm. The beneficial effects are as follows: the method is beneficial to setting production process parameters, evenly guiding and fetching the broken leaves, improving the splicing effect among the broken leaves, realizing the maximization of the area ratio of the broken leaves and achieving the maximization of the area ratio of the original tobacco leaves in the finished tobacco sheets.

Setting: the diameter of the mesh or the length of the diagonal line on the annular mesh belt is less than or equal to 0.3 mm; the annular net belt is always grounded and has zero potential in work.

To further describe the implementation of the method of the present invention, the following two specific embodiments are described:

example one

A reconstituted tobacco production line based on an electrostatic extraction process comprises: a crushed leaf screening and conveying device, an external fiber fluffing and metering conveyor 6, an electrostatic device, a crushed leaf spreader 4, a fiber spreader 5, a compactor, a coating and drying device and a coiling device.

The additional defibering and metering conveyor 6 comprises: the two-stage fiber fluffer, the storage tank and the fiber metering conveyor exist in the market.

Referring to fig. 1 and 2, the fiber spreader 5, the compactor, the coating and drying device, and the reeling or slicing device adopt related equipment required by the existing dry-method paper making or dry-method reconstituted tobacco, and in the first embodiment of the invention, the fiber spreader 5 is a set of drum screen type dry airflow forming heads.

The electrostatic device includes: the electrostatic generator and the electrostatic field leading device are used for forming a high-voltage electrostatic field; the electrostatic device is used for orderly taking the crushed leaves and transferring the crushed leaves to the left side of the discharge roller 21 by moving the pole needle 24 under the action of an electrostatic field.

Referring to fig. 4-8, 14, 18, the broken leaf spreader includes: the device comprises a feeder, a rotary drum 17, a transition plate 20, a discharge roller 21, a guide vane slot 22, a blowing box 18 and an air suction box 19.

The feeder is used for receiving and sending out the broken leaves from a feeding bin, and comprises: from last to setting gradually down: the device comprises a hopper 11, a spiral material distributing device 12, a material outlet and a feeding conveyor belt 13; the spiral material separating device 12 is used for uniformly distributing the crushed leaves on the feeding conveyor belt 13.

The drum 17 is located above the feeding conveyor 13 and comprises: two guide rollers 15, a chain wheel 16 and a needle plate 23; the needle plate 23 is made of conductive materials, the needle plate 23 is in a long strip shape, the side parts of a plurality of needle plates are hinged with each other, the hinges 26 at the hinged parts are mutually insulated, a closed flat long circular needle plate belt which is encircled between the two guide rollers 15 is formed, and the needle plates in the needle plate belt are mutually insulated; sprocket 16 links firmly two ends at guide roller 15, the both ends of faller 23 link firmly the chain link 25 by the insulating material preparation, chain link 25 meshes with sprocket 16, and when the drive when guide roller 15 is rotatory, sprocket 16 drives promptly the faller area rotary motion between two guide rollers.

And one end of the single needle plate is provided with a conductive brush which is used for being in sliding contact with a positive plate in the electrostatic field leading device or in sliding contact with a grounding end.

Referring to fig. 4, 5, 8 and 15, the discharge roller 21 is located at the lower right of the rotary drum 17, the transition plate 20 is located between the feeding conveyor belt 13 and the discharge roller 21, the guide vane groove 22 is located at the lower right of the discharge roller 21 and above the edge of the endless wire, the blow box 18 is located at the upper left of the rotary drum 17, and the suction box 19 is located at the lower right of the rotary drum 17.

The needle plate 23 is provided with through holes according to a set size, and moving pole needles 24 distributed outwards are fixedly connected in the through holes; every removes utmost point needle and is used for drawing a slice in the electrostatic field and is located the garrulous leaf on the pay-off conveyer belt 13 of removal utmost point needle 24 below to when taking the garrulous leaf to remove to and discharging roller 21 junction, garrulous leaf and the contact of discharging roller 21, remove utmost point needle 24 and garrulous leaf and lose static simultaneously, therefore garrulous leaf releases and drops to stator guide slot 22 from removing utmost point needle 24 in proper order, and garrulous leaf in stator guide slot 22 receives gravity and negative pressure air current effect, and the landing is in proper order and tiling on annular guipure 1, forms the aggregate.

Referring to fig. 19 and 20, a hollow conductive needle tube 24.1 is arranged inside the movable pole needle 24, the periphery of the conductive needle tube 24.1 is coated with an insulating layer 24.2, only the needle tip of the conductive needle tube 24.1 is exposed, and the root of the conductive needle tube is fixedly connected with the needle plate, so that the conductive needle tubes 24.1 on a single needle plate 23 are electrically connected in parallel, and each conductive needle tube 24.1 can be in sliding contact with the positive plate in the electrostatic field connection device or in sliding contact with the grounding terminal through a conductive brush arranged at one end of the needle plate 23, thereby realizing that the needle tip of the conductive needle tube 24.1 is charged with static electricity or grounded.

The transition plate 20 is a flat plate, and the length of the transition plate 20 is equal to the width of the needle plate strip; in operation, the transition plate 20 and the feeding conveyor belt 13 are both connected with the negative plate in the electrostatic field leading device.

Referring to fig. 5, 6 and 15, annular comb teeth uniformly distributed along the axial direction are machined on the outer circle of the discharge roller 21; in operation, the movable pole needle 24 under the rotary drum 17 moves forward from left to right, the discharging roller 21 rotates clockwise, when the movable pole needle 24 moves to the vicinity of the discharging roller 21, the needle point part of the conductive needle tube 24.1 is cut into the tooth gaps of the annular comb teeth, but the movable pole needle 24 is not contacted with the annular comb teeth.

In operation, when and only when the moving pole needle under the rotary drum moves to the position corresponding to the position of the feeding conveyor belt 13 and the transition plate 20, the needle plate 23 at the position corresponding to the position is in sliding contact with the positive plate through the brush, the moving pole needle is charged with static electricity, the needle plate is constructed to lead the crushed leaves to the needle point of the conductive needle tube 24.1 of the moving pole needle 24 and transfer the crushed leaves to the electrostatic field at the discharge roller 21, and the other moving pole needles 24 except the position corresponding to the position are grounded to zero potential.

Referring to fig. 4, 5, 16 and 17, the upper part of the left side of the guide vane slot 22 is provided with a slot which is in sliding contact with the tooth surface of the annular comb teeth of the discharge roller 21, the right side of the guide vane slot is provided with a slideway corresponding to the slot of the annular comb teeth of the discharge roller 21, and an included angle between the slideway and the mesh surface of the annular mesh belt is an obtuse angle; the slideway is used for receiving crushed leaves falling from the discharging roller 21, and the crushed leaves sequentially slide and are flatly paved on the annular mesh belt 1 under the action of gravity and negative pressure airflow.

Referring to fig. 6, 11 and 12, the blow box 18 is a positive pressure air box, and the air outlet surface of the blow box 18 is in sliding contact with the inner side surface of the needle plate strip; the air suction box 19 is a negative pressure air box, and the air inlet surface of the air suction box 19 is in sliding contact with the inner side surface of the needle plate belt; the blowing box 18 is used for cleaning the dust at the needle point of the conductive needle tube 24.1 of the moving polar needle 24, and the suction box 19 is used for adsorbing and holding the fragments which are electrostatically attracted on the needle point of the conductive needle tube 24.1 of the moving polar needle 24.

a. when the air suction box sucks air in a full-pressure state, the transition plate does not hold static electricity;

b. when the transition plate is charged with static electricity, the air suction box does not suck air;

c. the transition plate is charged with static electricity, and the air suction box is lower than the full-pressure state for air suction.

In the first embodiment, b is preferable.

As shown in fig. 2, in the first embodiment of the present invention, three sets, i.e., 1# -3 # of the crushed leaf spreaders are arranged in the crushed leaf spreader 4, the crushed leaves entering each set of the crushed leaf spreaders are equally distributed by the crushed leaf distributor 3, the width of each set of the crushed leaf spreaders is equal to that of the annular mesh belt 1, and each set of the crushed leaf spreaders are sequentially installed above the annular mesh belt 1 along the longitudinal direction of the annular mesh belt 1. In the specific implementation process, the following geometric positions are ensured: the mapping points of the moving polar needles of each group of the broken leaf spreading devices mapped on the annular mesh belt 1 are arranged in an equidistant and staggered mode, so that the broken leaf surfaces spread on the annular mesh belt 1 are not overlapped with each other, and the edge distance between the broken leaves is shortest.

In the first embodiment, the following are set: three groups of broken leaf spreading devices are arranged along the advancing longitudinal direction of the annular mesh belt 1, and meanwhile, the installation positions of the broken leaf spreading devices can be finely adjusted in mm level.

The relevant data on each broken leaf paver is set as follows:

refer to fig. 6, 11, 12, 15, 17, 19, 20.

In fig. 12, e represents the longitudinal center distance between the two air inlets, d represents the tooth pitch between the annular comb teeth on the discharge roller in fig. 15, h represents the tooth height of the annular comb teeth, d represents the distance between the two slide ways in fig. 17, and d represents the transverse distance between the two moving pole pins in fig. 19, which is equal to the tooth pitch d in fig. 15 and the slide way distance d in fig. 17; in FIG. 20, f represents the longitudinal spacing between two moving pole needles on the needle board, and the value of f is more than or equal to twice the value of e in FIG. 12.

Similarly, be provided with on the air inlet face of case that induced drafts along horizontal evenly distributed's rectangular form air intake, the width of air intake is less than remove the external diameter of utmost point needle, and set for: the distance between the air inlets is less than or equal to one half of the longitudinal distance of the movable pole needles.

The set values of the longitudinal and transverse distances between the movable polar needles are more than or equal to two times of the upper limit size in the broken leaf size interval value; to accommodate different size interval values of the crushed leaves.

The tooth height h value of the annular comb teeth is more than or equal to the upper limit size value of the size interval value of the crushed leaves.

In the first embodiment, an included angle between the slideway and the mesh surface of the annular mesh belt is set to be 100-120 degrees.

In the first embodiment, the electrostatic generator is a generator capable of generating a dc or ac high voltage electrostatic field, and the electric field intensity, the inter-electrode geometric distance and other parameters of the electrostatic field are formed by adjusting according to the prior art. When the method is specifically implemented, the moving speed of the annular mesh belt 1 is set, and then the comprehensive adjustment is carried out in sequence according to the moving speed: the moving speed of the spiral material distributing device 12, the feeding conveyor belt 13 and the moving pole needle 24 and the rotating speed of the discharging roller 21, and the moving speed of each mesh belt and the rotating speed of the winding device in the compactor, the upper spraying, the No. 1 drying box, the lower spraying and the No. 2 drying box shown in the figure 1; the speed or rotational speed adjustment modes comprise: AC frequency conversion or DC servo speed regulation.

The water content of the crushed leaves entering the hopper 1 is adjustable.

The air volume and the air pressure value of the air blowing box and the air suction box can be adjusted by the rotating speed of the fan.

As shown in fig. 2, vacuum boxes 1# F, 2# F and 3# F are arranged below the annular mesh belt 1 and at positions corresponding to each group of broken leaf spreading devices in the vertical direction, the vacuum boxes are used for adsorbing and positioning broken leaves falling from the sliding grooves on the annular mesh belt, the vacuum boxes are connected with negative pressure fans 1# F, 2# F and 3# F, and the rotating speed of each negative pressure fan can be adjusted during work.

As shown in fig. 1 and 2, the dry air-flow forming head 5 in the fiber spreader includes: a cylindrical screen; the cylindrical screen is positioned at the upper part of the dry airflow forming head 5, a scattering roller is arranged in the cylindrical screen, the annular mesh belt 1 is positioned below the cylindrical screen, and a vacuum box connected with an external negative pressure fan 4# F is arranged at the lower part of the annular mesh belt corresponding to the cylindrical screen; the cylinder screen receives the additional fiber from the additional fiber fluffing and metering conveyer.

The annular mesh belt 1 is encircled outside each vacuum box; when a layer of broken leaves is fully paved on the annular mesh belt 1 and enters the lower part of the cylindrical screen, the external fibers flow out of the screen holes of the cylindrical screen in a jet shape and are guided by the airflow of the corresponding vacuum box below the dry airflow forming head 5 to be stored in gaps among the broken leaves, and finally the broken leaves are interwoven into a whole continuous reconstituted tobacco substrate. Because the air permeability of the gaps among the crushed leaves is far higher than that of the crushed leaf surfaces, the storage amount of the added fibers on the crushed leaf surfaces is far less than that among the gaps of the crushed leaves.

The drying mode after coating includes: hot air penetrating drying and infrared drying; the drying device after coating includes: the reconstituted tobacco substrate is carried on a drying net belt and is dried in a penetrating manner by hot air; or the reconstituted tobacco substrate is suspended between heating sources through hot air penetration drying in an air floatation mode. In one embodiment of the present invention, the coating and drying apparatus comprises: go up spraying, 1# stoving case, lower spraying, 2# stoving case, the coating is in proper order with the stoving mode: the reconstituted tobacco substrate is carried on a set mesh belt in the processes of upper spraying, hot air penetrating drying, lower spraying and hot air penetrating drying.

Example two

A reconstituted tobacco production line based on a negative pressure drawing process comprises: broken leaves sieving and conveying device, external fiber fluffing and metering conveyor, leaves distributing device, fiber spreading device, pressing device, coating and drying device, and coiling or slicing device.

The structure of the crushed leaf sieving and conveying device, the additional fiber fluffing and metering conveyor, the fiber spreading device, the compactor, the coating and drying device and the coiling or slicing device is the same as that of the device with the same name in the first embodiment, the function of the device in the first embodiment is the same, and the installation position and the function of the device in the first embodiment are the same as those of the crushed leaf spreading device 4 in the first embodiment.

Referring to fig. 9, the leaf distributor includes: the device comprises a feeder, a rotary drum 17, a guide vane roller 21.1, a guide vane groove 22, a positive pressure box negative pressure box 19.1 and a clapboard 20.1; wherein: the structure of the feeder and the guide vane groove 22 is the same as that of the device with the same name in the first embodiment, and the function in the work is also the same, and the structure and the function in the work of the positive pressure box are the same as those of the air blowing box 18 in the first embodiment, so in the second embodiment, the positive pressure box is replaced by the air blowing box 18; the construction of the stator roller 21.1 is the same as that of the discharge roller 21 in the first embodiment.

As can be seen from comparing fig. 6 and fig. 9, in the second embodiment, the structure of the rotary drum 17 is the same as the structure and the installation position of the rotary drum 17 in the first embodiment, and the structure includes: two guide rollers 15, a chain wheel 16 and a needle plate 23; the needle plate 23 is in a long strip shape, and the side parts of a plurality of needle plates are hinged with each other to form a closed flat long circular needle plate belt which is encircled between two guide rollers; the sprocket 16 links firmly two ends at the deflector roll 15, the both ends of faller 23 link firmly chain link 25, chain link 25 meshes with sprocket 16, and when the drive deflector roll 15 is rotatory, sprocket 16 drives promptly the faller strip rotary motion between two deflector rolls 15.

The guide vane roller 21.1 is positioned at the right lower part of the rotary drum 17, and the guide vane groove 22 is positioned at the left lower part of the guide vane roller 21.1 and above the annular mesh belt 1.

The needle plate 23 is provided with through holes according to a set size, hollow moving needles which are distributed outwards are fixedly connected in the through holes, the structure and the installation mode of the hollow moving needles are the same as those of the moving pole needle 24 in the first embodiment, and the inner diameter of a needle tube at the needle point of each hollow moving needle is smaller than the diameter of the through hole in the needle plate; each hollow moving needle is used for guiding and taking a crushed blade on a feeding conveying belt right below, and when the crushed blade is driven to move to a joint with the guide vane roller, negative pressure is lost in the hollow moving needle, the crushed blade is released to the guide vane groove through the guide vane roller in sequence, and the crushed blade in the guide vane groove slides down and is tiled on the annular mesh belt in sequence under the action of gravity and negative pressure airflow to form aggregate.

The air blowing box 18 is used for cleaning the broken powder at the needle point of the moving pole needle; the negative pressure box 19.1 is positioned between the two guide rollers 15 in the rotary drum 17, and the air inlet surface of the negative pressure box 19.1 is in sliding contact with the inner side surface of the needle plate strip; the negative pressure box 19.1 is used for sucking and holding the crushed leaves at the needle point of the hollow moving needle.

The guide vane roller 21.1 rotates oppositely to the moving direction of the hollow moving needle in work, but the hollow moving needle is not contacted with the annular comb teeth; when the hollow moving needle moves to the vicinity of the guide vane roller 21.1, the needle point of the hollow moving needle cuts into the tooth gaps of the annular comb teeth with the crushed leaves, and then the crushed leaves fall onto the guide vane groove 22 due to pressure loss.

As shown in fig. 9, the upper part of the right side of the guide vane slot 22 is provided with a slot in sliding contact with the tooth surface of the annular comb teeth of the guide vane roller 21.1, the right side of the guide vane slot is provided with a slide way corresponding to the slot of the annular comb teeth of the guide vane roller, and an included angle between the slide way and the mesh surface of the annular mesh belt is an obtuse angle; the slideway is used for receiving crushed leaves falling from the guide vane roller 21.1, and the crushed leaves sequentially slide and are flatly paved on the annular mesh belt 1 under the action of gravity and negative pressure airflow.

The clapboard 20.1 is positioned between the upper part of the annular mesh belt and the lower part of the feeding conveyor belt 13, and the clapboard 20.1 is used for receiving scattered crushed leaves above and transferring the scattered crushed leaves to an externally arranged crushed leaf recovery device (not shown in the figure) in a transverse vibration mode for recycling.

In the second embodiment of the invention, three groups of blade distributors are arranged, the width of each blade distributor is equal to that of the annular mesh belt 1, and each group of blade distributors are sequentially arranged above the annular mesh belt 1 along the longitudinal direction of the advancing annular mesh belt 1. In the specific implementation process, the following steps are required to be ensured: the mapping points of the hollow moving needles of each group of leaf distributors mapped on the annular mesh belt 1 are arranged in an equidistant and staggered mode, so that the leaf surfaces of the crushed leaves spread on the annular mesh belt 1 are not overlapped with each other, and the edge distance between the crushed leaves is shortest.

In the second embodiment, the following settings are set:

three groups of leaf distributing devices are sequentially arranged along the advancing longitudinal direction of the annular mesh belt 1, and the installation positions of the leaf distributing devices can be finely adjusted;

the relevant parameters on each leaf distributor are set as follows:

referring to fig. 9, 11, 12, 15, 17, 19 and 20, e in fig. 12 represents the longitudinal center distance between two air inlets.

In the second embodiment, the structure of the guide vane roller 21.1 is the same as the structure of the discharge roller 21 in the first embodiment, so that a pitch value d between the annular comb teeth on the discharge roller is also equal to a pitch value between the annular comb teeth on the guide vane roller 21.1, h represents a tooth height of the annular comb teeth, and d represents a pitch between two slideways in fig. 17.

D in fig. 19 represents the transverse spacing between the two mobile polar needles, which is also equal to the transverse spacing between the two hollow mobile needles, which is equal to the tooth spacing d in fig. 15 and the slideway spacing d in fig. 17; in FIG. 20, f represents the longitudinal distance between two movable polar needles on the needle plate, which is equal to the longitudinal distance between two hollow movable needles, and the value of f is more than or equal to twice the value of e in FIG. 12.

The air outlet surface of the air blowing box 18 is provided with strip-shaped air outlets which are uniformly distributed along the transverse direction, and the width of each air outlet is smaller than the outer diameter of the hollow moving needle and is set as follows: the distance between the air outlets is less than or equal to one half of the longitudinal distance of the hollow moving needle.

Similarly, be provided with along the rectangular form air intake of horizontal evenly distributed on the air inlet face of negative pressure box 19.1, the width of air intake is less than the external diameter of hollow removal needle, and set for: the distance between the air inlets is less than or equal to one half of the longitudinal distance of the hollow moving needle.

The set values of the longitudinal and transverse distances between the hollow moving needles are more than or equal to two times of the upper limit size of the broken leaf size interval value; to accommodate different size interval values of the crushed leaves. The tooth height h value of the annular comb teeth is more than or equal to the upper limit size value of the size interval value of the crushed leaves.

In the second embodiment, the included angle between the slideway and the mesh surface of the annular mesh belt 1 is set to be 100-120 degrees.

In the work, the moving speed of the annular net belt 1 is preset, and then the comprehensive adjustment is carried out in sequence according to the moving speed: the moving speed of the spiral material distributing device 12, the feeding conveyor belt 13, the hollow moving needle and the rotating speed of the discharging roller 21, and the moving speed of each mesh belt and the rotating speed of the winding device in the compactor, the upper spraying device, the No. 1 drying box, the lower spraying device and the No. 2 drying box shown in the figure 1; the speed or rotational speed adjustment modes comprise: AC frequency conversion or DC servo speed regulation.

The water content of the crushed leaves entering the hopper 1 is adjustable;

Referring to fig. 2, the dry air-forming head 5 in the fiber spreader includes: a cylindrical screen; the cylindrical screen is positioned at the upper part of the dry airflow forming head 5, a scattering roller is arranged in the cylindrical screen, the annular mesh belt 1 is positioned below the cylindrical screen, and a vacuum box connected with an external negative pressure fan 4# F is arranged at the lower part of the annular mesh belt corresponding to the cylindrical screen; the cylinder screen receives the additional fiber from the additional fiber fluffing and metering conveyer.

The drying mode after coating includes: hot air penetrating drying and infrared drying; the drying device after coating includes: the reconstituted tobacco substrate is carried on a drying net belt and is dried in a penetrating manner by hot air; or the reconstituted tobacco substrate is suspended between heating sources through hot air penetration drying in an air floatation mode. In one embodiment of the present invention, the coating and drying apparatus comprises: go up spraying, 1# stoving case, lower spraying, 2# stoving case, the coating is with the stoving mode: the reconstituted tobacco substrate is carried on a set mesh belt in the processes of upper spraying, hot air penetrating drying, lower spraying and hot air penetrating drying.

It needs to be further explained that: in the second embodiment of the present invention, the structure of the hollow moving needle and the position of the hollow moving needle mounted on the needle plate are set to be the same as those of the first embodiment, and in order to reduce the related cost in manufacturing, especially to adapt to small-sized broken leaves manufacturing, the hollow moving needle and the position of the needle plate may be set to be different, specifically: the hollow movable needle in the second embodiment does not need an insulating coating layer, so that the outer diameter of the hollow movable needle can be made smaller, and therefore, the hollow movable needles on the needle plate can be arranged more densely.

In the first or second embodiment of the present invention:

additional fibers include, but are not limited to: one or a mixture of at least two of all-wood fluff pulp fibers, hemp pulp fibers or tobacco stem fibers.

In the coating device, the components of the coating include but are not limited to: the coating is sprayed in the prior dry method reconstituted tobacco process, or dipped in the wet paper-making reconstituted tobacco, or chitosan-containing coating with good compatibility with natural tobacco shreds in the cigarette production line is directly prepared.

The beneficial effects that can be obtained by adopting the invention are as follows:

compared with the existing wet paper-making method, dry method, rolling method or thick pulp method, the tobacco residue is crushed and then processed. The invention selects the tobacco broken leaves with set specification only by a physical method, spreads the selected broken leaves on an annular net belt evenly and orderly by an electrostatic extraction or negative wind pressure extraction mode, interweaves additional fibers by a dry airflow forming device to be stored in gaps among the broken leaves, and finally interweaves the broken leaves into a whole continuous reconstituted tobacco substrate. Because the air permeability of the gaps among the crushed leaves is far higher than that of the crushed leaf surfaces, the storage amount of the added fibers on the crushed leaf surfaces is far less than that among the gaps of the crushed leaves.

Compared with the prior various reconstituted tobacco processes, the process provided by the invention is simple and feasible, requires less equipment, requires low energy consumption per unit yield, has less pollution emission in the production process, and is easy to treat or recover.

Experiments show that in the technical scheme of the invention, the ratio of the gap area between the crushed tobacco leaves to the reconstituted tobacco leaf substrate area is less than or equal to 30% by optimally selecting the electrostatic field voltage and the structural size, the installation position, the operation parameters and the like of a device such as a rotary drum, a slideway and the like, so that the proportion of the original natural tobacco leaves in the prepared tobacco sheet finished product is higher than that of any existing reconstituted tobacco leaf method or device.

By adopting the technical scheme of the invention, the physical representation, chemical composition and suction evaluation of the manufactured reconstituted tobacco meet or are superior to the requirements specified by the standard YC/T16.3-2003.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be considered as limiting the present invention.

In the present invention, unless otherwise specifically stated or limited, the terms "mounted," "connected," "fixed," "secured," and the like are to be construed broadly, e.g., as meaning a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

Claims

1. A reconstituted tobacco method is a broken-leaf-based mending-seam reconstituted tobacco process, and comprises the following steps: aggregate preparation process, substrate preparation process and the working procedures of pressing, coating, drying, reeling or slicing; the method is characterized in that:

the preparation process of the aggregate comprises the following steps: the crushed leaves screened out according to the set mesh size are sequentially and uniformly paved on a movable bearing body in an orderly manner by a suction and transfer method to form a layer of aggregate which is adsorbed on the bearing body and is spliced by the crushed leaves;

the substrate preparation process is to add additional fibers into gaps among the crushed tobacco leaves by using an airflow sedimentation method, fill and sew the gaps in the aggregate, and prepare the whole reconstituted tobacco substrate;

the pressing, coating, drying, coiling or slicing process is to use the existing dry-type paper-making method reconstituted tobacco equipment to make the reconstituted tobacco substrate into a rolled or flaky tobacco sheet in a pressing, coating, drying, coiling or slicing mode;

the supporting body is a flat annular mesh belt, a vacuum box connected with a negative pressure fan is arranged below the annular mesh belt, and the annular mesh belt is used for adsorbing and driving the aggregate to longitudinally move forward and transfer to the subsequent process;

the sucking and transferring method comprises the following steps: one or a combination of two of the electrostatic extraction and transfer process and the negative pressure extraction and transfer process.

2. The reconstituted tobacco method of claim 1, wherein: the electrostatic pick-up and transfer process comprises: arranging a plurality of movable polar needles, a discharge roller and a guide vane groove which are orderly arranged according to a set size, wherein the movable polar needles are used for sequentially guiding the crushed leaves in an electrostatic field, driving the crushed leaves to move to one side of the discharge roller, eliminating charges on the crushed leaves, and then enabling the crushed leaves to fall onto the guide vane groove, and the crushed leaves in the guide vane groove are sequentially slid and tiled on the annular mesh belt under the action of gravity and negative pressure airflow to form aggregate;

3. The reconstituted tobacco method of claim 1, wherein: the crushed leaves comprise: tobacco dust and/or tobacco fragments in the form of pieces; setting: the crushed leaves are sheet-shaped objects with the maximum value of the overall dimension of 0.5-3.5 mm; but in the process of forming the aggregate, the difference of the external dimensions of each crushed leaf for drawing is less than or equal to 1.5 mm; that is, the values of the physical dimension interval of each crushed leaf are respectively: 0.5-2.0 mm, 1.0-2.5 mm, 1.5-3.0 mm, 2.0-3.5 mm;

4. The reconstituted tobacco method of claim 1, wherein: the additional fibers comprise: one or a mixture of at least two of all-wood fluff pulp fiber, hemp pulp fiber or tobacco stalk fiber;

the coating for coating includes: one of spraying paint used in the existing dry method reconstituted tobacco process, or extract paint used in the wet paper-making method reconstituted tobacco, or viscous extract paint containing chitosan component.

5. A reconstituted tobacco production line based on an electrostatic extraction process comprises: a crushed leaf screening and conveying device, an external fiber fluffing and metering conveyor, an electrostatic device, a crushed leaf spreader, a fiber spreader, a compactor, a coating and drying device and a coiling or slicing device; the additional fiber defibering and metering conveyor comprises: the existing two-stage fiber fluffer, storage tank and fiber metering conveyor in the market; the fiber spreader, the compactor, the coating and drying device and the reeling or slicing device adopt related equipment required by the existing dry-method paper making or dry-method reconstituted tobacco, wherein the fiber spreader is at least one group of drum sieve type dry-method airflow forming heads; the broken leaf screening and conveying device comprises: a screening machine and a feeding bin; the screening machine is an existing airflow flotation machine and is used for screening crushed leaves with the external dimension of a set interval value from tobacco residues mixed with tobacco powder, crushed stems and tobacco fragments and storing the selected crushed leaves into a feeding bin; the electrostatic device includes: the electrostatic generator and the electrostatic field leading device are used for forming a high-voltage electrostatic field; the electrostatic device is used for orderly leading the crushed leaves by moving the pole needle and transferring the crushed leaves to one side of the discharging roller under the action of an electrostatic field; the electrostatic field connecting and guiding device comprises: a positive plate and a negative plate; the method is characterized in that:

the broken leaf spreading device comprises: the device comprises a feeder, a rotary drum, a transition plate, a discharge roller, a guide vane groove, a blowing box and an air suction box;

the feeder is used for receiving and sending out the broken leaves that come from the feed bin, includes from last to setting gradually down: the device comprises a hopper, a spiral material distributing device, a material outlet and a feeding conveyor belt; the spiral distributing device is used for uniformly distributing the crushed leaves on the feeding conveyor belt;

the rotary drum is located the top of pay-off conveyer belt, includes: two guide rollers, chain wheels and needle plates; the needle plates are made of conductive materials, the needle plates are in a strip shape, the side parts of the needle plates are hinged with each other, the hinges at the hinged parts are mutually insulated, a closed flat long circular needle plate belt surrounding between the two guide rollers is formed, and the needle plates in the needle plate belt are mutually insulated; the chain wheels are fixedly connected to two ends of the guide rollers, chain links made of insulating materials are fixedly connected to two ends of the needle plate, the chain links are meshed with the chain wheels, and when the guide rollers are driven to rotate, the chain wheels drive the needle plate to rotate between the guide rollers;

one end of the single needle plate is provided with a conductive brush which is used for being in sliding contact with the electrostatic field leading device or the grounding end;

the discharging roller is positioned at the right lower part of the rotary drum, the transition plate is positioned between the feeding conveyor belt and the discharging roller, the guide vane groove is positioned below the discharging roller and above the annular mesh belt, the blowing box is positioned at the left upper part in the rotary drum, and the air suction box is positioned at the right lower part in the rotary drum;

the needle plate is provided with a plurality of through holes according to a set size, and each through hole is fixedly connected with a movable polar needle which is distributed outwards; each movable polar needle is used for guiding a crushed leaf on a feeding conveyor belt below the movable polar needle in an electrostatic field, and driving the crushed leaf to move to a junction with a discharging roller, the crushed leaf is contacted with the discharging roller, the movable polar needle and the crushed leaf lose static electricity at the same time, then the crushed leaf is released from the movable polar needle in sequence and falls into a guide vane groove, and the crushed leaf in the guide vane groove slides down and is tiled on an annular net belt in sequence under the action of gravity and negative pressure airflow to form aggregate;

the movable pole needle is internally provided with a hollow conductive needle tube, the periphery of the conductive needle tube is coated with an insulating layer, only the needle tip part of the conductive needle tube is exposed, and the root part of the conductive needle tube is fixedly connected with the needle plate, so that the conductive needle tubes on a single needle plate are electrically connected in parallel, and a conductive brush at one end of the needle plate can be in sliding contact with a positive plate in the electrostatic field leading device or in sliding contact with a grounding end, so that the needle tip part of the conductive needle tube is electrified with static electricity or grounded;

the transition plate is a flat plate, and the length of the transition plate is equal to the width of the needle plate strip; in work, the transition plate and the feeding conveyor belt are both communicated with a negative plate in the electrostatic field guiding device;

annular comb teeth which are uniformly distributed along the axial direction are machined on the outer circle of the discharge roller; during operation, when the movable pole needle below the rotary drum rotates from left to right, the discharge roller rotates clockwise, when the movable pole needle moves to the position near the discharge roller, the needle point part of the conductive needle tube is cut into the tooth gaps of the annular comb teeth, but the movable pole needle is not contacted with the annular comb teeth;

in the work, when and only when the movable pole needle below the rotary drum moves to the position corresponding to the feeding conveyor belt and the transition plate, the needle plate at the position corresponding to the position is in sliding contact with the positive plate through the conductive brush, the movable pole needle is charged with static electricity to form an electrostatic field which can lead the crushed leaves to the needle point of the conductive needle tube and transfer the crushed leaves to the discharge roller, and other movable pole needles except the position corresponding to the movable pole needle are grounded to have zero potential;

the upper part of the left side of the guide vane groove is provided with a slot which is in sliding contact with the tooth surface of the annular comb teeth of the discharge roller, the right side of the guide vane groove is provided with a slideway corresponding to the tooth seam of the annular comb teeth of the discharge roller, and an included angle between the slideway and the mesh surface of the annular mesh belt is an obtuse angle; the slideway is used for receiving crushed leaves falling from the discharging roller, and the crushed leaves sequentially slide and are flatly laid on the annular net belt under the action of gravity and negative pressure airflow;

the air blowing box is a positive pressure air box, and the air outlet surface of the air blowing box is in sliding contact with the inner side surface of the needle plate belt; the air suction box is a negative pressure air box, and an air inlet surface of the air suction box is in sliding contact with the inner side surface of the needle plate belt; the air blowing box is used for cleaning the crushed powder at the needle point of the conductive needle tube, and the air suction box is used for adsorbing and holding the fragments which are attracted to the needle point of the conductive needle tube by means of static electricity;

be provided with along horizontal evenly distributed's rectangular form air outlet on the air-out face of case of blowing, the width of air outlet is less than remove the external diameter of utmost point needle, and set for: the distance between the air outlets is less than or equal to one half of the longitudinal distance of the movable pole needles;

be provided with on the air inlet face of case that induced drafts along horizontal evenly distributed's rectangular form air intake, the width of air intake is less than remove the external diameter of utmost point needle, and set for: the distance between the air inlets is less than or equal to one half of the longitudinal distance of the movable pole needle;

setting in work: the state of the air suction box and the transition plate in the working process is one of the following three states:

6. The reconstituted tobacco production line based on the electrostatic extraction process as claimed in claim 5, wherein: the broken leaf spreading device is provided with at least two groups, broken leaves entering each group of the broken leaf spreading device are distributed in equal amount through the arranged broken leaf distributor, the width of each group of the broken leaf spreading device is equal to that of the annular net belt, and each group of the broken leaf spreading device is sequentially arranged above the annular net belt along the longitudinal direction of the advancing annular net belt and is ensured from the geometric position: the mapping points of the movable polar needles of each group of the broken leaf spreading devices mapped on the annular mesh belt are arranged in an equidistant and staggered way;

setting in work:

the number of the broken leaf spreading devices and the relative installation position among the broken leaf spreading devices can be finely adjusted by mm level;

the interval between the removal utmost point needle on each broken leaf spreading device includes:

the set values of the longitudinal and transverse distances between the movable polar needles are more than or equal to two times of the upper limit size in the broken leaf size interval value;

an included angle between the slideway on the guide vane groove and the net surface of the annular net belt is an obtuse angle;

adjusting the electric field intensity of an electrostatic field and adjusting the geometric distance between electrodes;

comprehensive regulation: the spiral material distributing device, the feeding conveyor belt, the moving pole needles, the moving speed of the annular mesh belt and the rotating speed of the discharging roller; the speed or rotational speed adjustment modes comprise: AC frequency conversion or DC servo speed regulation;

adjusting the water content of the crushed leaves;

7. The reconstituted tobacco production line based on the electrostatic extraction process as claimed in claim 5, wherein: the vacuum box is positioned below the annular mesh belt and vertically corresponds to each group of the broken leaf spreading devices, is used for adsorbing and positioning the broken leaves falling from the sliding grooves on the annular mesh belt, is connected with an external negative pressure fan, and can adjust the rotating speed of each negative pressure fan in work; the endless mesh belt is wrapped around the outside of each vacuum box.

8. A reconstituted tobacco production line based on a negative pressure drawing process comprises: a crushed leaf screening and conveying device, an external fiber fluffing and metering conveyor, a leaf distributor, a fiber spreader, a compactor, a coating and drying device and a coiling or slicing device; the additional fiber defibering and metering conveyor comprises: the existing two-stage fiber fluffer, storage tank and fiber metering conveyor in the market; the fiber spreader, the compactor, the coating and drying device and the reeling or slicing device adopt related equipment required by the existing dry-method paper making or dry-method reconstituted tobacco, wherein the fiber spreader is at least one group of drum sieve type dry-method airflow forming heads;

the broken leaf screening and conveying device comprises: a screening machine and a feeding bin; the screening machine is an existing airflow flotation machine and is used for screening crushed leaves with the external dimension of a set interval value from tobacco residues mixed with tobacco powder, crushed stems and tobacco fragments and storing the selected crushed leaves into a feeding bin; the method is characterized in that:

the leaf distributing device comprises: the device comprises a feeder, a rotary drum, a guide vane roller, a guide vane groove, a positive pressure box and a negative pressure box;

the rotary drum is located the top of pay-off conveyer belt, includes: two guide rollers, chain wheels and needle plates; the needle plates are in a long strip shape, and the side parts of the needle plates are hinged with each other to form a closed flat long circular needle plate belt which is encircled between the two guide rollers; the chain wheels are fixedly connected to two ends of the guide rollers, two ends of the needle plate are fixedly connected with chain links, the chain links are meshed with the chain wheels, and when the guide rollers are driven to rotate, the chain wheels drive the needle plate belt to rotate between the two guide rollers;

the guide vane roller is positioned at the right lower part of the rotary drum, and the guide vane groove is positioned at the left lower part of the guide vane roller and above the annular mesh belt;

the needle plate is provided with a plurality of through holes according to a set size, hollow moving needles which are distributed outwards are fixedly connected in the through holes, and the inner diameter of a needle tube at the needle point of each hollow moving needle is smaller than the diameter of the through hole in the needle plate; each hollow moving needle is used for guiding a crushed blade on a feeding conveyor belt positioned right below and driving the crushed blade to move to a joint with the guide vane roller, negative pressure in the hollow moving needle is lost, the crushed blade is released to the guide vane groove through the guide vane roller in sequence, and the crushed blade in the guide vane groove slides down and is tiled on the annular mesh belt in sequence under the action of gravity and negative pressure airflow to form aggregate;

the positive pressure box is positioned at the upper left part in the rotary drum, the air outlet surface of the positive pressure box is in sliding contact with the inner side surface of the needle plate strip, and the positive pressure box is used for cleaning the broken powder at the needle point of the movable pole needle; the negative pressure box is positioned between two guide rollers below the positive pressure box in the rotary drum, and the air inlet surface of the negative pressure box is in sliding contact with the inner side surface of the needle plate strip; the negative pressure box is used for sucking and holding the crushed leaves at the needle point of the hollow moving needle;

be provided with along horizontal evenly distributed's rectangular form air outlet on the air-out face of positive pressure case, the width of air outlet is less than the external diameter of hollow removal needle, and set for: the distance between the air outlets is less than or equal to one half of the longitudinal distance of the hollow moving needle;

be provided with along horizontal evenly distributed's rectangular form air intake on the air inlet face of negative pressure tank, the width of air intake is less than the external diameter of hollow removal needle, and set for: the distance between the air inlets is less than or equal to one half of the longitudinal distance of the hollow moving needle;

annular comb teeth which are uniformly distributed along the axial direction are machined on the outer circle of the guide vane roller; in the work, the guide vane roller and the hollow moving needle rotate in opposite directions, but the hollow moving needle is not contacted with the annular comb teeth; when the hollow moving needle moves to the position near the guide vane roller, the needle point at the front end of the hollow moving needle is cut into the tooth gaps of the annular comb teeth with crushed leaves, and the crushed leaves fall onto the guide vane groove due to pressure loss;

the upper part of the right side of the guide vane groove is provided with a slot which is in sliding contact with the tooth surface of the annular comb teeth of the guide vane roller, the left side of the guide vane groove is provided with a slide way which corresponds to the tooth seam of the annular comb teeth of the guide vane roller, and an included angle between the slide way and the mesh surface of the annular mesh belt is an obtuse angle; the slideway is used for receiving crushed leaves falling from the guide vane roller, and the crushed leaves sequentially slide and are flatly laid on the annular net belt under the action of gravity and negative pressure airflow;

a partition plate is arranged between the lower part of the feeding conveyor belt and the upper part of the annular mesh belt and is used for receiving scattered crushed leaves above the partition plate and transferring the scattered crushed leaves to an externally arranged crushed leaf recovery device.

9. The reconstituted tobacco production line based on the negative pressure extraction process as claimed in claim 8, wherein: the leaf distributor is provided with at least two groups, the width of the leaf distributor is equal to that of the annular net belt, and the leaf distributors in each group are sequentially arranged above the annular net belt along the advancing longitudinal direction of the annular net belt and are ensured from the geometric position: the mapping points of the hollow moving needles of each group of leaf distributors mapped on the annular mesh belt are arranged in an equidistant and staggered way;

setting in work:

the number of the leaf distributing devices and the installation positions among the leaf distributing devices can be finely adjusted in mm level;

the interval between the hollow moving needle on each leaf distributor includes: the transverse spacing between the hollow moving needles is equal to the tooth pitch on the guide vane roller and the spacing between the slideways on the guide vane grooves respectively; the set values of the longitudinal and transverse distances between the hollow moving needles are more than or equal to two times of the upper limit size of the broken leaf size interval value;

adjusting the water content of the crushed leaves;

10. The reconstituted tobacco production line based on the negative pressure extraction process as claimed in claim 8, wherein: the vacuum box is positioned below the annular mesh belt and vertically corresponds to each group of leaf distributing devices, is used for adsorbing and positioning broken leaves falling from the sliding grooves on the annular mesh belt, is connected with an external negative pressure fan, and can adjust the rotating speed of each negative pressure fan in work; the endless mesh belt is wrapped around the outside of each vacuum box.