CN113716292A

CN113716292A - Belt weighing type feeder belt sticky coal cleaning device

Info

Publication number: CN113716292A
Application number: CN202111042200.XA
Authority: CN
Inventors: 郭霖; 付小东; 王兴泉; 刘志卿; 江明; 朱致军; 杨佩
Original assignee: Huaneng Qinmei Ruijin Power Generation Co Ltd
Current assignee: Huaneng Qinmei Ruijin Power Generation Co Ltd
Priority date: 2021-09-07
Filing date: 2021-09-07
Publication date: 2021-11-30
Anticipated expiration: 2041-09-07
Also published as: CN113716292B

Abstract

The invention discloses a belt sticky coal cleaning device of a belt weighing type coal feeder, which comprises a cleaning assembly, wherein the cleaning assembly comprises a roller, a storage barrel and a storage cavity; the recovery assembly comprises an air outlet and a rotary port; and a heating assembly connected to the storage chamber. Has the advantages that: through set up the clearance subassembly in the device, the storage barrel on the clearance subassembly can be under the rotatory effect of cylinder, scrapes moist cinder scraper, accomodates the storage intracavity. Meanwhile, the heating component heats the storage cavity to high temperature, and dries the wet coal cinder. On the other hand, the air outlet on the roller and the rotary ports on two sides of the roller can discharge dried coal slag, and the coal slag can be reused. The device has simple structure, not only solves the problem that the moist coal slag is difficult to treat, but also reduces the shutdown cleaning time of the coal feeder and greatly improves the working efficiency.

Description

Belt weighing type feeder belt sticky coal cleaning device

Technical Field

The invention relates to the technical field of relevant equipment of coal feeders, in particular to a belt weighing type coal feeder belt sticky coal cleaning device.

Background

The sticky coal cleaning device designed by a manufacturer in the belt weighing type coal feeder is fixed in counter weight, the contact distance between the sticky coal cleaning device and a belt and the sticky coal cleaning force on the belt are fixed, no adjustment measure is provided in operation, the sticky coal cleaning device cannot adapt to the change of coal types and the change of the dryness and wetness of coal, and a thick layer of coal is adhered to the belt in the rainy season in spring, spring and summer in the south and when raining in winter at low temperature. The coal sticking of the belt can cause a series of problems of coal breaking of the coal feeder, belt deviation, belt slipping and the like, and great troubles are caused to the safe and stable operation of the coal mill and the boiler. In order to clean the coal adhered to the coal feeder, at present, only the coal is thrown into a raw coal bunker, inserted rods are inserted on an empty belt, and the coal feeder is idle for cleaning, but a peak shaving unit participates in deep peak shaving or when the load of a boiler is low in continuous rainy days, the coal feeder is adhered more and frequently, the condition of stopping a set of pulverizing system is not met, or the condition of stopping the operation of the coal feeder at the moment can possibly cause unstable combustion of the boiler.

In addition, the sticky coal cleaning and handling work ticket of the coal feeder can control the working time of sticky coal cleaning only by closely matching the operating personnel and the maintainers, and a large amount of manpower and material resources are input when the sticky coal is accumulated frequently, so that the safety is not facilitated, and the economic benefit is not good.

Disclosure of Invention

This section is for the purpose of summarizing some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. In this section, as well as in the abstract and the title of the invention of this application, simplifications or omissions may be made to avoid obscuring the purpose of the section, the abstract and the title, and such simplifications or omissions are not intended to limit the scope of the invention.

The invention is provided in view of the problem that the coal cinder on the belt of the existing coal feeder is difficult to clean.

Therefore, the invention aims to provide a belt sticky coal cleaning device of a belt weighing type coal feeder.

In order to solve the technical problems, the invention provides the following technical scheme: a belt sticky coal cleaning device of a belt weighing type coal feeder comprises a cleaning assembly, a cleaning assembly and a conveying assembly, wherein the cleaning assembly comprises a roller, a storage barrel and a storage cavity, the storage barrel is communicated with the roller and extends outwards, and the storage cavity is formed in the roller; the recovery assembly comprises an air outlet connected to the roller and rotary ports arranged on two sides of the roller; and a heating assembly connected to the storage chamber.

As a preferred scheme of the belt sticky coal cleaning device of the belt weighing type coal feeder, the belt sticky coal cleaning device comprises the following components: the cylinder circumference equipartition is a plurality of storage cylinder, storage chamber is connected to the storage barrel.

As a preferred scheme of the belt sticky coal cleaning device of the belt weighing type coal feeder, the belt sticky coal cleaning device comprises the following components: the storage barrel is connected to the outer side of the roller, a storage opening is formed in one side, away from the roller, of the storage barrel, and a metal gasket is arranged on the lower side of the storage opening.

As a preferred scheme of the belt sticky coal cleaning device of the belt weighing type coal feeder, the belt sticky coal cleaning device comprises the following components: the joint of the storage barrel and the storage cavity is provided with a backflow preventing iron sheet, and the backflow preventing iron sheet is fixed on a fixing block inside the storage cavity.

As a preferred scheme of the belt sticky coal cleaning device of the belt weighing type coal feeder, the belt sticky coal cleaning device comprises the following components: the side surface of the roller is connected with a rotating shaft, a through hole is formed in the rotating shaft, and the through hole is communicated with the storage cavity.

As a preferred scheme of the belt sticky coal cleaning device of the belt weighing type coal feeder, the belt sticky coal cleaning device comprises the following components: an exhaust cover is arranged on the upper side of the exhaust outlet, and an automatic part is arranged at the joint of the exhaust cover and the exhaust outlet.

As a preferred scheme of the belt sticky coal cleaning device of the belt weighing type coal feeder, the belt sticky coal cleaning device comprises the following components: the rotary ports are arranged on two sides of the roller, a plurality of rotary ports are circumferentially and uniformly distributed on two sides of the roller, and the rotary ports are communicated with the storage cavity.

As a preferred scheme of the belt sticky coal cleaning device of the belt weighing type coal feeder, the belt sticky coal cleaning device comprises the following components: the heating assembly comprises a fan and a heating wire, the heating wire is arranged in a through hole in the rotating shaft, and the fan is connected with the through hole.

As a preferred scheme of the belt sticky coal cleaning device of the belt weighing type coal feeder, the belt sticky coal cleaning device comprises the following components: a filter screen is arranged on one side, close to the storage cavity, of the through hole, and the filter screen is fixed inside the through hole.

As a preferred scheme of the belt sticky coal cleaning device of the belt weighing type coal feeder, the belt sticky coal cleaning device comprises the following components: and connecting covers are arranged on two sides of the roller and are in threaded connection with the roller.

The invention has the beneficial effects that: through set up the clearance subassembly in the device, the storage barrel on the clearance subassembly can be under the rotatory effect of cylinder, scrapes moist cinder scraper, accomodates the storage intracavity. Meanwhile, the heating component heats the storage cavity to high temperature, and dries the wet coal cinder. On the other hand, the air outlet on the roller and the rotary ports on two sides of the roller can discharge dried coal slag, and the coal slag can be reused. The device has simple structure, not only solves the problem that the moist coal slag is difficult to treat, but also reduces the shutdown cleaning time of the coal feeder and greatly improves the working efficiency.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise. Wherein:

FIG. 1 is a schematic diagram of the overall structure of a belt sticky coal cleaning device of a belt weighing type coal feeder.

FIG. 2 is a schematic connection diagram of the belt sticky coal cleaning device of the belt weighing type coal feeder.

FIG. 3 is a schematic diagram of an electrical internal structure of the belt sticky coal cleaning device of the belt weighing type coal feeder.

FIG. 4 is a partial structural schematic diagram of a cleaning assembly and a recovery assembly of the belt sticky coal cleaning device of the belt weighing type coal feeder.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.

Furthermore, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one implementation of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

Furthermore, the present invention is described in detail with reference to the drawings, and in the detailed description of the embodiments of the present invention, the cross-sectional view illustrating the structure of the device is not enlarged partially according to the general scale for convenience of illustration, and the drawings are only exemplary and should not be construed as limiting the scope of the present invention. In addition, the three-dimensional dimensions of length, width and depth should be included in the actual fabrication.

Example 1

Referring to fig. 1 and 2, a belt sticky coal cleaning device of a belt weighing type coal feeder comprises a cleaning assembly 100, wherein the cleaning assembly 100 comprises a roller 101, a storage barrel 102 communicated with the roller 101 and extending outwards, and a storage cavity 103 formed in the roller 101; a recovery assembly 200, wherein the recovery assembly 200 comprises an air outlet 201 connected to the drum 101 and a rotation outlet 202 arranged on both sides of the drum 102; and a heating assembly 300, the heating assembly 300 being connected to the inside of the storage chamber 103.

Specifically, the main structure of the present invention comprises a base assembly 100, a recovery assembly 200 and a heating assembly 300, and in this embodiment, the cleaning assembly 100 comprises a roller 101, a receiving tube 102 communicating with the roller 101 and extending outwards, and a storage chamber 103 opened inside the roller 101. The roller 101 is cylindrical, so that the motor can drive the structure to move conveniently. The particular arcuate configuration of the receiver 102 allows for easy scraping of the coal residue that is attached to the pulley. The storage chamber 103 is provided with a smooth inner wall and the cylindrical inner chamber also helps the coal slag to roll inside the storage chamber 103.

Further, the recovery unit 200 includes an air discharge port 201 connected to the drum 101 and a rotation port 202 provided on both sides of the drum 102. The air outlet 201 has two functions, one can be timely the discharge heating element 300 blow into the inside hot-blast of storage chamber 103, on the other hand, after long-time operation, the storage chamber 103 is inside can remain a lot of cinder and not discharge, sets up the air outlet 201 at the cylinder 102 outer wall and can discharge remaining cinder more easily. The rotary ports 202 are passages for discharging mainly coal cinder, the coal cinder is accumulated to a certain height after the storage chamber 103 is rotated and dried, and is discharged through the rotary ports 202 arranged at the outer side of the middle of the drum 102, and the discharge of the coal cinder can be accelerated by arranging a plurality of rotary ports 202.

Meanwhile, the heating assembly 300 is connected into the storage cavity 103, the heating assembly 300 is a direct structure for treating the wet coal cinder, the heating assembly 300 can adopt various forms, can adopt the structure of a fan and a heating wire to generate hot air to be blown into the storage cavity 103, and can be discharged through the air outlet 201 after long-time operation.

The operation process is as follows: before the operator cleans the cinder, the operator fixedly connects the device on the shell of the belt weighing coal feeder, and the device is positioned right above the belt pulley. When the moist coal slag is transported to the position of the storage cylinder 102 of the device through the belt pulley, the roller 102 starts to operate, under the operation of the roller 102, the storage cylinder 102 scrapes the moist coal slag adhered to the surface of the belt pulley under the action of rotation, and under the special structure of the storage cylinder 102, the coal slag flows to the storage cavity 103. At this time, the heating assembly 300 is turned on to heat the storage chamber, and the coal slag can be rapidly dried while the drum 102 continuously rotates. After a period of drying, the coal slag overflows to the turning port 202 and flows out through the turning port 202. Meanwhile, the air outlet 201 can be opened at regular time, so that residual coal slag can be cleaned, and dried hot air can be discharged.

Example 2

Referring to fig. 1-4, this embodiment differs from the first embodiment in that: the drum 101 has a plurality of receivers 102 arranged circumferentially, and the receivers 102 are connected to a storage chamber 103. The receiving cylinder 102 is connected to the outside of the drum 101, a receiving opening 104 is provided on the side of the receiving cylinder 102 away from the drum, and a metal gasket 105 is provided under the receiving opening 104. A backflow prevention iron sheet 106 is arranged at the joint of the containing barrel 102 and the storage cavity 103, and the backflow prevention iron sheet 106 is fixed on a fixing block 106a in the storage cavity 103. The side surface of the drum 101 is connected with a rotating shaft 107, a through hole 108 is formed in the rotating shaft 107, and the through hole 108 is communicated with the storage chamber 103.

An exhaust cover 203 is arranged on the upper side of the exhaust port 201, and an automatic part 204 is arranged at the joint of the exhaust cover 201 and the exhaust port 201. The rotary ports 202 are arranged on two sides of the roller 103, a plurality of rotary ports 202 are uniformly distributed on the two sides of the roller 103 in the circumferential direction, and the rotary ports 202 are communicated with the storage cavity 103. The drum 101 is provided at both sides with connection covers 109, and the connection covers 109 are screw-coupled with the drum 101.

Specifically, in the present embodiment, a plurality of storage barrels 102 are uniformly distributed in the circumferential direction of the drum 101, and the storage barrels 102 are connected to the storage chamber 103, so that the efficiency can be improved by the plurality of storage barrels 102. The receiving cylinder 102 is connected to the outside of the drum 101, a receiving opening 104 is provided on the side of the receiving cylinder 102 away from the drum, and a metal gasket 105 is provided under the receiving opening 104. A backflow prevention iron sheet 106 is arranged at the joint of the containing barrel 102 and the storage cavity 103, and the backflow prevention iron sheet 106 is fixed on a fixing block 106a in the storage cavity 103. The special structure of the arc-shaped containing cylinder 102 is very favorable for the coal cinder attached to the belt pulley by the spatula, the metal gasket 105 can slow down the abrasion of the containing opening 104, when the containing opening 104 is used for scraping, the lower side can be frequently contacted with the outer surface of the belt, and the metal gasket 105 can not only prevent the rapid abrasion of the containing opening 104, but also can be replaced in time. The anti-backflow iron sheet 106 is made of light metal, and one end of the anti-backflow iron sheet is fixed on the fixed block 106a, and the other end of the anti-backflow iron sheet is arranged at the tail end of the storage barrel 102 close to the direction of the storage cavity 103 in a hanging mode. When the cinder is scraped and flows along with the inside of the containing cavity and reaches the position of the anti-backflow iron sheet 106, the cinder rushes away the obstruction of the anti-backflow iron sheet 106 and enters the storage cavity 103. However, as the drum 101 rotates, the coal slag in the storage chamber 103 may want to flow out of the receiving cylinder 104, and the backflow prevention iron piece 106 may hinder the flowing-out of the rotating coal slag.

Further, a rotation shaft 107 is connected to a side surface of the drum 101, a through hole 108 is formed in the rotation shaft 107, and the through hole 108 communicates with the storage chamber 103. The rotating shaft 107 is arranged outside the roller 101, the rotating shaft 107 is connected with a motor inside the coal feeder, the motor drives the rotating shaft 107 to rotate, the rotating shaft 107 simultaneously drives the roller 101 to rotate, and the rotation of the roller 101 can be controlled by controlling the rotating speed of the motor. The rotating shaft 107 is formed with a through hole 108 therein, the through hole 108 is connected to the storage chamber 103, and the through hole 108 is mainly connected to the heating unit 300.

Further, an exhaust cover 203 is arranged on the upper side of the exhaust port 201, and an automatic part 204 is arranged at the joint of the exhaust cover 201 and the exhaust port 201. The rotary ports 202 are arranged on two sides of the roller 103, a plurality of rotary ports 202 are uniformly distributed on the two sides of the roller 103 in the circumferential direction, and the rotary ports 202 are communicated with the storage cavity 103. The drum 101 is provided at both sides with connection covers 109, and the connection covers 109 are screw-coupled with the drum 101. The exhaust cover 203 and the exhaust port 201 are automatically connected through an automatic piece 204, and the opening of the exhaust cover 203 can be controlled by a control button in a remote control mode. The arrangement of the automatic part 204 can avoid the operator to open the exhaust cover 203 manually, and the working condition of the coal cinder is not suitable for manual operation of personnel. The plurality of the rotary ports 202 are formed in the side wall of the drum 103, so that the coal slag can be discharged rapidly under the rotation of the drum 103, and the accumulation in the storage chamber 103 is prevented. The level of the return opening 202 in the interior of the storage chamber 103 at an intermediate position also prevents incorrect setting of the direct discharge of the coal dust which has just entered the storage chamber 103 without drying.

The rest of the structure is the same as in example 1.

The operation process is as follows: when collecting the wet coal cinder, the motor is turned on, the motor drives the rotating shaft 107 to rotate and simultaneously drives the roller 103 to rotate, and the containing cylinder 102 outside the roller 103 also rotates along with the rotating shaft. When the cinder is on the conveyer belt surface, when the storage port 104 on the storage barrel 102, storage port 104 can scrape the belt surface, and the cinder is scraped and gets into inside the storage barrel 102, flows to the anti-backflow iron sheet 106 along with the curved inner chamber of storage barrel 102, under the effect of weight, flushes anti-backflow iron sheet 106, gets into storage chamber 103. At the moment, the roller 103 is in operation all the time, the coal slag is stirred up in the rolling process, when the coal slag is accumulated to a certain height in the storage chamber 103, the coal slag flows out through the rotary opening 202 at the center of the roller 103, and the flowing fine coal slag falls on the surface of the conveyor belt to be continuously utilized.

Example 3

Referring to fig. 1-4, this embodiment differs from the above embodiments in that: the heating assembly 300 comprises a blower 301 and a heating wire 302, the heating wire 302 is disposed in the through hole 108 inside the rotation shaft 107, and the blower 301 is connected to the through hole 108. A filter screen 303 is arranged at one side of the through hole 108 close to the storage cavity 103, and the filter screen 303 is fixed inside the through hole 108. The drum 101 is provided at both sides with connection covers 109, and the connection covers 109 are screw-coupled with the drum 101.

Specifically, the heating assembly 300 includes a blower 301 and a heater wire 302, the heater wire 302 is disposed in the through hole 108 inside the rotating shaft 107, and the blower 301 is connected to the through hole 108. A filter screen 303 is arranged at one side of the through hole 108 close to the storage cavity 103, and the filter screen 303 is fixed inside the through hole 108. Fan 301 sets up in the cylinder 101 outside, and fan 301 cooperates with heater strip 302, can last for the inside hot-blast of providing of storage chamber 103 through-hole 108, and hot-blast moist cinder that can accelerate storage chamber 103 is dried. In order to prevent the coal cinder from flowing out of the storage cavity 103 through the rotary opening 202 and flowing back to the fan, a filter screen 303 is arranged on one side of the through hole 108 close to the storage cavity 103, so that the coal cinder can be effectively prevented from overflowing.

Further, the drum 101 is provided with connection covers 109 at both sides thereof, and the connection covers 109 are screw-coupled with the drum 101. The connection cover 109 can be detached and coupled to the drum 101. The connecting cover 109 is designed such that when the inside of the drum 101 is damaged for maintenance, the connecting cover 103 can be opened so that the structure inside the storage chamber 103 can be replaced and maintained in time.

The rest of the structure is the same as in example 2.

The operation process is as follows: before the drum 101 starts to operate, the fan 301 may be turned on, the fan 301 and the heating wire 302 may pass through the through hole 108 to continuously supply hot air to the storage chamber 103, and the coal cinder inside the storage chamber 103 is dried quickly by the rotation of the drum 101 and the drying of the hot air. In the operation process, the air outlet 201 can be opened at regular time, and turbid hot air can be cleaned at regular time.

It is important to note that the construction and arrangement of the present application as shown in the various exemplary embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters (e.g., temperatures, pressures, etc.), mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited in this application. For example, elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of this invention. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. In the claims, any means-plus-function clause is intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present inventions. Therefore, the present invention is not limited to a particular embodiment, but extends to various modifications that nevertheless fall within the scope of the appended claims.

Moreover, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not be described (i.e., those unrelated to the presently contemplated best mode of carrying out the invention, or those unrelated to enabling the invention).

It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.

It should be noted that the above-mentioned embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the claims of the present invention.

Claims

1. The utility model provides a belt weighing type feeder belt sizing cleaning device which characterized in that: comprises the steps of (a) preparing a mixture of a plurality of raw materials,

the cleaning assembly (100) comprises a roller (101), a storage barrel (102) which is communicated with the roller (101) and extends outwards, and a storage cavity (103) which is formed in the roller (101);

the recycling assembly (200) comprises an air outlet (201) connected to the drum (101) and rotary outlets (202) arranged on two sides of the drum (102); and the number of the first and second groups,

a heating assembly (300), the heating assembly (300) being connected within the storage chamber (103).

2. The belt-weighing coal feeder belt sticky coal cleaning device of claim 1, characterized in that: the roller (101) is provided with a plurality of receiving cylinders (102) which are uniformly distributed in the circumferential direction, and the receiving cylinders (102) are connected to a storage cavity (103).

3. The belt-weighing coal feeder belt sticky coal cleaning device as claimed in claim 2, wherein: the storage barrel (102) is connected to the outer side of the roller (101), a storage opening (104) is formed in one side, away from the roller, of the storage barrel (102), and a metal gasket (105) is arranged on the lower side of the storage opening (104).

4. The belt-weighing coal feeder belt sticky coal cleaning device of claim 3, characterized in that: a backflow preventing iron sheet (106) is arranged at the joint of the storage barrel (102) and the storage cavity (103), and the backflow preventing iron sheet (106) is fixed on a fixing block (106a) inside the storage cavity (103).

5. The belt-weighing coal feeder belt sticky coal cleaning device of claim 4, characterized in that: the side surface of the roller (101) is connected with a rotating shaft (107), a through hole (108) is formed in the rotating shaft (107), and the through hole (108) is communicated with the storage cavity (103).

6. The belt-weighing coal feeder belt sticky coal cleaning device as claimed in any one of claims 1 or 5, wherein: exhaust cover (203) is provided with to air exit (201) upside, exhaust cover (201) and air exit (201) junction are provided with from moving part (204).

7. The belt-weighing coal feeder belt sticky coal cleaning device of claim 6, characterized in that: the rotary ports (202) are arranged on two sides of the roller (103), a plurality of rotary ports (202) are circumferentially and uniformly distributed on two sides of the roller (103), and the rotary ports (202) are communicated with the storage cavity (103).

8. The belt-weighing coal feeder belt sticky coal cleaning device of claim 7, characterized in that: the heating assembly (300) comprises a fan (301) and a heating wire (302), the heating wire (302) is arranged in a through hole (108) in the rotating shaft (107), and the fan (301) is connected with the through hole (108).

9. The belt-weighing coal feeder belt sticky coal cleaning device of claim 8, characterized in that: one side of the through hole (108) close to the storage cavity (103) is provided with a filter screen (303), and the filter screen (303) is fixed in the through hole (108).

10. The belt-weighing coal feeder belt sticky coal cleaning device of claim 9, characterized in that: and connecting covers (109) are arranged on two sides of the roller (101), and the connecting covers (109) are in threaded connection with the roller (101).