Preparation process of hollow fiber ultrafiltration membrane
Technical Field
The invention relates to the technical field of water purification equipment, and particularly provides a preparation process of a hollow fiber ultrafiltration membrane.
Background
In the field of water purification, the ultrafiltration technology is a high-tech water purification technology which is widely applied to solution separation and concentration, extraction of useful substances from wastewater and purification and reutilization of wastewater, and has the advantages of simple use process, no need of heating, energy conservation, low-pressure operation, small occupied area of the device and the like.
The hollow fiber ultrafiltration membrane is one of ultrafiltration membranes, and the adoption of a hollow fiber ultrafiltration membrane material as a filter membrane material is the most mature and advanced technology in the ultrafiltration technology. The hollow fiber ultrafiltration membrane tube is a tubular filter membrane structure which takes a hollow fiber ultrafiltration membrane as a filter membrane material, micropores are distributed on the tube wall of the hollow fiber ultrafiltration membrane tube, the aperture is larger in the molecular weight of trapped substances, and the trapped molecular weight can reach thousands to hundreds of thousands.
In the production and manufacturing process of the hollow fiber ultrafiltration membrane tube, the hollow fiber ultrafiltration membrane tube with a certain length specification is required to be obtained according to the specific water purifying equipment to be assembled, so that the hollow fiber ultrafiltration membrane tube material is required to be cut at a fixed length, and the following problems mainly exist in the traditional cutting process:
1) a single hollow fiber ultrafiltration membrane tube is adopted for cutting, so that the cutting efficiency is low;
2) the mode that the multiple hollow fiber ultrafiltration membrane tubes are cut in batches is adopted for cutting, and the consistency of the length specification of each cut hollow fiber ultrafiltration membrane tube is not easy to guarantee in the cutting process.
Based on the problems, the invention provides a preparation process of a hollow fiber ultrafiltration membrane, and particularly relates to a preparation device of the hollow fiber ultrafiltration membrane.
Disclosure of Invention
In order to solve the above problems, the present invention provides a process for preparing a hollow fiber ultrafiltration membrane, which is used to solve the above problems mentioned in the background art.
In order to achieve the purpose, the invention adopts the following technical scheme to realize the purpose: a preparation process of a hollow fiber ultrafiltration membrane specifically comprises the following steps:
s1, fixed length adjustment: according to the length of the hollow fiber ultrafiltration membrane tube to be cut, the distance between the cutting mechanism and the reference baffle is adjusted through the cutting movement adjusting mechanism, and in addition, the cutting avoiding plate component is correspondingly adjusted in a sliding mode, so that fixed-length cutting can be realized by taking the reference baffle as a reference datum;
s2, positioning and discharging: positioning a plurality of filter membrane tubes to be cut on a positioning template mechanism, and enabling the tube end of each filter membrane tube to be tightly attached to a reference baffle;
s3, fixed-length cutting: the cutting mechanism is used for simultaneously cutting all the filter membrane tubes placed on the positioning template mechanism at a fixed length;
s4, centralized unloading: the cut filter membrane tubes are intensively unloaded into a stacking mechanism through an automatic unloading mechanism;
s5, stacking and finishing: automatically arranging the discharged filter membrane tubes by a stacking mechanism to realize orderly stacking;
the hollow fiber ultrafiltration membrane preparation process adopting the steps S1-S5 also specifically relates to a hollow fiber ultrafiltration membrane preparation device in the process of preparing the hollow fiber ultrafiltration membrane, which comprises a rack, wherein a positioning groove plate mechanism and a stacking mechanism are sequentially arranged on the rack in the horizontal direction, a cutting movement adjusting mechanism is arranged on the rack, a cutting mechanism positioned above the positioning groove plate mechanism is arranged on the cutting movement adjusting mechanism, and an automatic discharging mechanism for automatically discharging materials is arranged on the positioning groove plate mechanism; wherein:
the cutting and avoiding mechanism comprises a fixed groove plate, a cutting and avoiding groove plate component and a discharging groove plate which are sequentially arranged in the horizontal straight line direction, wherein the fixed groove plate is horizontally and fixedly installed on the rack, the cutting and avoiding groove plate component comprises a first groove plate and a second groove plate hinged with the first groove plate, a cutting and avoiding gap is reserved at the hinged position between the first groove plate and the second groove plate, two first guide rods arranged in a sliding manner with the fixed groove plate are arranged on the side wall of the first groove plate, two second guide rods arranged in a sliding manner with the discharging groove plate are arranged on the side wall of the second groove plate, and a horizontal adjusting cylinder used for driving the cutting and avoiding groove component to integrally and horizontally move is arranged on the bottom end surface of the discharging groove plate;
the upper end face of the fixed groove plate is provided with a plurality of first-section positioning grooves, the upper end face of the first groove plate is provided with a plurality of second-section positioning grooves, the upper end face of the second groove plate is provided with a plurality of third-section positioning grooves, the upper end face of the discharging groove plate is provided with a plurality of fourth-section positioning grooves, and the cross section profiles of the first-section positioning grooves, the second-section positioning grooves, the third-section positioning grooves and the fourth-section positioning grooves are coincided in a one-to-one correspondence mode under the axial visual angle of the first guide rod;
the automatic discharging mechanism is fixedly arranged on the rack and connected with the bottom end of the discharging trough plate;
the cutting moving adjusting mechanism can drive the cutting mechanism to axially move along the first guide rod.
Preferably, the cutting removes adjustment mechanism includes that the level rotates to be installed just be located in the frame the adjustment pivot, two fixed mounting of a groove board subassembly below are kept away in the cutting frame upper end and mirror symmetry distribute and be in slide rail and two one-to-one slip of a groove board subassembly both sides are kept away in the cutting are two the inboard sliding base of slide rail, sliding base follows the frame up end is worn out downwards sliding base's bottom is provided with the rack, be equipped with two one-to-one and two in the adjustment pivot rack toothing's adjusting gear.
Preferably, the cutting mechanism comprises a beam frame which spans the cutting clearance groove plate component and is fixedly installed between the upper end surfaces of the two sliding bases, a cutting cylinder vertically fixed at the top end of the beam frame, and a cutting blade fixed at the bottom output end of the cutting cylinder.
Preferably, the automatic discharging mechanism comprises a transverse plate, two supporting assemblies and two discharging cylinders, the transverse plate is positioned below the discharging trough plate and is horizontally fixed on the rack, two guide rails are arranged on the transverse plate, the guide direction of the guide rails is parallel to the axial direction of the first guide rod, the two supporting assemblies are correspondingly arranged between the two guide rails and the bottom end face of the discharging trough plate one by one, and two ends of the two discharging cylinders are hinged between the transverse plate and the discharging trough plate;
the supporting assembly comprises a guide pillar, a sliding block and a supporting spring, the top end of the guide pillar is hinged to the bottom end face of the discharging chute plate, the sliding block is horizontally arranged on the guide rail in a sliding mode, the supporting spring is sleeved on the guide pillar in a sleeved mode, the guide pillar and the sliding block are vertically arranged in a sliding mode, and two ends of the supporting spring are connected between the top end of the guide pillar and the upper end of the sliding block.
Preferably, the stacking mechanism comprises a semi-cylinder fixed on the frame, the semi-cylinder is arranged downwards from a position close to the discharge chute plate in an inclined manner, an inclined included angle between the semi-cylinder and a horizontal plane is 10-20 degrees, the opening of the semi-cylinder is arranged upwards, semi-circular guide rails sharing the same circle center with the semi-cylinder are arranged on inner end faces on two sides of the semi-cylinder, an arc plate with a semi-circular structure is rotatably arranged between the two semi-circular guide rails, a circular cutting type avoiding hole with a semi-circular structure is formed in the cylindrical surface of the semi-cylinder, a fan-shaped gear ring penetrating through the avoiding hole is arranged on the outer arc surface of the arc plate, arc guide rods are connected to two ends of the fan-shaped gear ring, the other end of each arc guide rod is connected to the frame, the circle center of the arc of each arc guide rod is overlapped with the circle center of the fan-shaped gear ring, and a reset spring is sleeved on each arc guide rod, reset spring's both ends fixed connection be in fan-shaped ring gear tip with between the frame be located in the frame the horizontal fixed mounting in semicircle below has motor fixed partition, fixed mounting has driving motor on the motor fixed partition up end, be equipped with on driving motor's the output shaft with fan-shaped ring gear meshed's incomplete gear.
Preferably, the two sides of the cutting blade are provided with a material pressing cotton block, and the lower end face of the material pressing cotton block is provided with a plurality of position avoiding grooves which are opposite to the plurality of two-section positioning grooves or the plurality of three-section positioning grooves one by one.
Preferably, hand wheels are arranged at two ends of the adjusting rotating shaft.
The technical scheme has the following advantages or beneficial effects:
the invention provides a hollow fiber ultrafiltration membrane preparation process, in particular to a hollow fiber ultrafiltration membrane preparation device, which can perform movable adjustment on a cutting mechanism by using a set cutting movable adjusting mechanism with a set reference baffle as a reference, then perform fixed-length cutting aiming at hollow fiber ultrafiltration membrane tubes with different length specifications, perform corresponding adjustment on the fixed-length adjustment operation by using a set positioning notch plate mechanism, position and place a plurality of hollow fiber ultrafiltration membrane tubes to be cut by using the set cutting mechanism, automatically cut a batch of hollow fiber ultrafiltration membrane tubes by using the set automatic discharging mechanism, complete automatic discharging after the cutting is completed by using the set automatic discharging mechanism, collect a plurality of hollow fiber ultrafiltration membrane tubes which are automatically discharged in a set stacking mechanism in a centralized manner, and automatically arrange the hollow fiber ultrafiltration membrane tubes in the stacking mechanism to realize regular stacking, the device related in the preparation process can finish automatic fixed-length cutting of a batch of hollow fiber ultrafiltration membrane tubes according to length specification standards, greatly improves cutting efficiency, ensures the consistency of the length and the size of the hollow fiber ultrafiltration membrane tubes after cutting and forming, can perform automatic discharging and automatic sorting and collection after cutting, and solves the trouble of manual sorting and collection in the production and preparation process.
Drawings
The invention and its features, aspects and advantages will become more apparent from reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings. The drawings, in which like numerals refer to like parts throughout the several views and which are not necessarily drawn to scale, emphasis instead being placed upon illustrating the principles of the invention.
FIG. 1 is a process flow diagram of a hollow fiber ultrafiltration membrane preparation process provided by the present invention;
FIG. 2 is a schematic perspective view of a hollow fiber ultrafiltration membrane manufacturing apparatus according to the present invention at a viewing angle;
FIG. 3 is an enlarged partial schematic view at A in FIG. 2;
FIG. 4 is a schematic perspective view of a hollow fiber ultrafiltration membrane manufacturing apparatus according to the present invention from another perspective;
FIG. 5 is an enlarged partial schematic view at B in FIG. 4;
FIG. 6 is an enlarged partial schematic view at C of FIG. 4;
FIG. 7 is an enlarged partial schematic view at D of FIG. 4;
FIG. 8 is a side view of a hollow fiber ultrafiltration membrane preparation apparatus according to the present invention;
FIG. 9 is another side view of a hollow fiber ultrafiltration membrane preparation apparatus according to the present invention.
In the figure: 1. a frame; 11. a reference baffle; 2. a positioning slot plate mechanism; 21. fixing the groove plate; 211. a section of positioning groove; 22. cutting the avoiding groove plate component; 221. a first groove plate; 2211. a second section of positioning groove; 222. a second groove plate; 2221. three sections of positioning grooves; 223. a first guide rod; 224. a second guide rod; 23. a discharge chute plate; 231. four sections of positioning grooves; 24. a horizontal adjusting cylinder; 3. a cutting movement adjusting mechanism; 31. adjusting the rotating shaft; 311. an adjusting gear; 312. a hand wheel; 32. a slide rail; 33. a slide base; 331. a rack; 4. a cutting mechanism; 41. a beam frame; 42. cutting the air cylinder; 43. a cutting blade; 431. pressing cotton blocks; 4311. a position avoiding groove; 5. an automatic discharge mechanism; 51. a transverse plate; 511. a guide rail; 52. a support assembly; 521. a guide post; 522. a slider; 523. a support spring; 53. a discharge cylinder; 6. a stacking mechanism; 61. a semi-cylinder; 611. a semicircular guide rail; 612. avoiding holes; 62. a circular arc plate; 621. a sector-shaped gear ring; 63. a circular arc guide rod; 64. a return spring; 65. the motor fixes the baffle plate; 66. a drive motor; 661. incomplete gear.
Detailed Description
The following detailed description of the embodiments of the present invention will be given with reference to the accompanying drawings for the purpose of providing those skilled in the art with a more complete, accurate and thorough understanding of the concept and technical solution of the present invention, and to facilitate the implementation thereof, but not to limit the present invention.
Referring to the attached drawings 1-9, a preparation process of a hollow fiber ultrafiltration membrane specifically comprises the following steps:
s1, fixed length adjustment: according to the length of the hollow fiber ultrafiltration membrane tube to be cut, the distance between the cutting mechanism 4 and the reference baffle 11 is adjusted through the cutting movement adjusting mechanism 3, and in addition, the cutting clearance plate component is correspondingly adjusted in a sliding mode, so that fixed-length cutting can be realized by taking the reference baffle 11 as a reference;
s2, positioning and discharging: positioning a plurality of filter membrane tubes to be cut on the positioning template mechanism 2, and enabling the tube end of each filter membrane tube to be tightly attached to the reference baffle 11;
s3, fixed-length cutting: the cutting mechanism 4 is used for simultaneously cutting all the filter membrane tubes placed on the positioning template mechanism 2 at a fixed length;
s4, centralized unloading: the cut filter membrane tubes are intensively unloaded into a stacking mechanism 6 through an automatic unloading mechanism 5;
s5, stacking and finishing: the discharged filter membrane tubes are automatically arranged through a stacking mechanism 6, so that orderly stacking is realized;
the hollow fiber ultrafiltration membrane preparation process adopting the steps S1-S5 also specifically relates to a hollow fiber ultrafiltration membrane preparation device in the process of preparing the hollow fiber ultrafiltration membrane, and the hollow fiber ultrafiltration membrane preparation device comprises a rack 1, wherein a positioning groove plate mechanism 2 and a stacking mechanism 6 are sequentially arranged on the rack 1 in the horizontal direction, a cutting movement adjusting mechanism 3 is arranged on the rack 1, a cutting mechanism 4 positioned above the positioning groove plate mechanism 2 is arranged on the cutting movement adjusting mechanism 3, and an automatic discharging mechanism 5 for automatically discharging materials is arranged on the positioning groove plate mechanism 2;
the positioning groove plate mechanism 2 is sequentially arranged in a fixed groove plate 21, a cutting avoiding groove 4311 plate component 22 and a discharging groove plate 23 in the horizontal straight line direction, the fixed groove plate 21 is horizontally welded and fixedly installed on the frame 1, the cutting avoiding groove 4311 plate component 22 comprises a first groove plate 221 and a second groove plate 222 hinged with the first groove plate 221, a cutting avoiding gap is reserved at the hinged position between the first groove plate 221 and the second groove plate 222, two first guide rods 223 arranged in a sliding manner with the fixed groove plate 21 are arranged on the side wall of the first groove plate 221, two second guide rods 224 arranged in a sliding manner with the discharging groove plate 23 are arranged on the side wall of the second groove plate 222, and a horizontal adjusting cylinder 24 used for driving the cutting avoiding groove 4311 component to integrally and horizontally move is arranged on the bottom end face of the discharging groove plate 23; the fixed slot plate 21 and the discharge slot plate 23 are fixed relatively, and the plate mechanism of the cutting avoiding slot 4311 can slide left and right between the fixed slot plate 21 and the discharge slot plate 23.
The frame 1 is provided with a reference baffle 11 which is positioned at the front side of the discharging chute plate 23 and is used as a positioning reference.
The cutting movement adjusting mechanism 3 can drive the cutting mechanism 4 to move axially along the first guide rod 223; the cutting moving adjusting mechanism 3 comprises an adjusting rotating shaft 31 which is horizontally and rotatably installed on the rack 1 and located below the cutting avoiding groove 4311 plate component 22, two sliding rails 32 which are welded at the upper end of the rack 1 and are symmetrically distributed at two sides of the cutting avoiding groove 4311 plate component 22 in a mirror-image manner and two sliding bases 33 which slide on the inner sides of the two sliding rails 32 in a one-to-one manner, the sliding bases 33 penetrate out of the upper end face of the rack 1, a rack 331 is arranged at the bottom end of the sliding bases 33, two adjusting gears 311 which are meshed with the two racks 331 in a one-to-one manner are arranged on the adjusting rotating shaft 31, and hand wheels 312 are arranged at two ends of the adjusting rotating shaft 31.
In the actual manufacturing process of the hollow fiber ultrafiltration membrane tube, hollow fiber ultrafiltration membrane tubes with different length specifications are obtained according to different assembly environment requirements, and therefore, the step S1 of adjusting the fixed length is required to be executed according to the length of the hollow fiber ultrafiltration membrane tube to be obtained actually, on one hand, the hand wheel 312 on any side is manually rotated to drive the adjusting rotating shaft 31 to rotate, so that the adjusting rotating shaft 31 drives the rack 331 through the adjusting gear 311, thereby driving the two sliding bases 33 to slide along the sliding rail 32 synchronously, further driving the whole cutting mechanism 4 to move synchronously along with the two sliding bases 33, taking the reference baffle 11 as a reference, so that the distance between the cutting blade 43 and the reference baffle 11 after adjustment is equal to the length of the hollow fiber ultrafiltration membrane tube to be obtained by cutting, on the other hand, after the movement adjustment of the cutting mechanism 4 is completed, the whole cutting avoiding groove 4311 plate component 22 is pushed to move leftwards or rightwards by starting the horizontal adjusting cylinder 24, then, after the cutting avoiding groove 4311 plate assembly 22 moves horizontally, the cutting blade 43 falls just above the cutting avoiding gap between the first groove plate 221 and the second groove plate 222.
Fifteen first-section positioning grooves 211 are uniformly formed in the upper end face of the fixed groove plate 21, fifteen second-section positioning grooves 2211 are uniformly formed in the upper end face of the first groove plate 221, fifteen third-section positioning grooves 2221 are uniformly formed in the upper end face of the second groove plate 222, fifteen fourth-section positioning grooves 231 are uniformly formed in the upper end face of the discharge groove plate 23, and the cross-sectional profiles of the fifteen first-section positioning grooves 211, the fifteen second-section positioning grooves 2211, the fifteen third-section positioning grooves 2221 and the fifteen fourth-section positioning grooves 231 are correspondingly overlapped one by one under the axial visual angle of the first guide rod 223.
After the length-fixed adjustment of the step S1 is completed, the step S2 of positioning and discharging may be performed to place the hollow fiber ultrafiltration membrane tubes to be cut on the positioning notch plate mechanism 2, specifically, fifteen hollow fiber ultrafiltration membrane tubes to be cut are sequentially passed through one-to-one correspondence from fifteen sets of the first positioning notch 211, the second positioning notch 2211, the third positioning notch 2221 and the fourth positioning notch 231, and the tube end of each hollow fiber ultrafiltration membrane tube is in contact with the reference baffle 11.
The cutting mechanism 4 comprises a beam frame 41 which crosses over the cutting clearance groove 4311 plate component 22 and is fixedly arranged between the upper end surfaces of the two sliding bases 33 through bolts, a cutting cylinder 42 which is vertically fixed at the top end of the beam frame 41 through bolts, and a cutting blade 43 which is fixed at the bottom output end of the cutting cylinder 42; two sides of the cutting blade 43 are provided with the cotton pressing block 431, and the lower end surface of the cotton pressing block 431 is provided with fifteen spacing grooves 4311 which are opposite to the fifteen two-section positioning grooves 2211 or the fifteen three-section positioning grooves 2221 one by one.
After the positioning and discharging of the step S2 are completed, the fixed-length cutting of the step S3 can be executed to perform formal cutting, specifically, the cutting cylinder 42 is started to drive the cutting blade 43 to move downwards, so that the batch cutting of fifteen hollow fiber ultrafiltration membrane tubes is completed, in the cutting process, the first groove plate 221 and the second groove plate 222 are distributed on two sides of the cutting blade 43 to provide support for the lower ends of two sides of the cut of the hollow fiber ultrafiltration membrane tubes, and the two pressing cotton blocks 431 provide flexible compression for the upper ends of two sides of the cut, so that the cutting mechanism 4 can complete the cutting.
The automatic discharging mechanism 5 is fixedly arranged on the frame 1 and is connected with the bottom end of the discharging trough plate 23; the automatic discharging mechanism 5 comprises a transverse plate 51, two supporting assemblies 52 and two discharging cylinders 53, the transverse plate 51 is positioned below the discharging trough plate 23 and is horizontally welded on the rack 1, two guide rails 511 are arranged on the transverse plate 51, the guiding directions of the guide rails 511 are parallel to the axial direction of a first guide rod 223, the two supporting assemblies 52 are correspondingly arranged between the two guide rails 511 and the bottom end surface of the discharging trough plate 23 one by one, and two ends of the two discharging cylinders 53 are hinged between the transverse plate 51 and the discharging trough plate 23;
the supporting assembly 52 comprises a guide pillar 521 whose top end is hinged to the bottom end face of the discharging chute plate 23, a sliding block 522 horizontally slidably arranged on the guide rail 511, and a supporting spring 523 sleeved on the guide pillar 521, wherein the guide pillar 521 and the sliding block 522 are vertically slidably arranged, and two ends of the supporting spring 523 are welded between the top end of the guide pillar 521 and the upper end of the sliding block 522.
After the cutting is finished, the step S4 of centralized discharging operation can be executed, that is, the automatic discharging is finished by the automatic discharging mechanism 5, specifically, the whole body formed by the second slot plate 222 and the discharging slot plate 23 (the second slot plate 222 is hinged with the first slot plate 221, and the second slot plate 222 and the discharging slot plate 23 are connected in series through the second guide rod 224 to form a structure which can be turned around the hinged shaft) is inclined downwards from the horizontal state by starting the two discharging cylinders 53, the cut hollow fiber ultrafiltration membrane tube slides down to the arc plate 62 along the discharging slot plate 23, during the discharging process, the guide pillar 521 slides vertically downwards along the slide block 522, the supporting spring 523 is compressed, and the slide block 522 slides along the guide rail 511 to one side of the cutting avoiding slot 4311 plate assembly 22; after the automatic discharging is completed, the discharging chute plate 23 is retreated to the initial state again.
The stacking mechanism 6 comprises a semi-cylinder 61 welded on the frame 1, the semi-cylinder 61 is arranged downwards from the position close to the discharge chute plate 23 in an inclined manner, the inclined included angle between the semi-cylinder 61 and the horizontal plane is 10 degrees, the opening of the semi-cylinder 61 is arranged upwards, semi-circular guide rails 611 which are concentric with the semi-cylinder 61 are arranged on the inner end surfaces of the two sides of the semi-cylinder 61, an arc plate 62 with a semi-circular structure is rotatably arranged between the two semi-circular guide rails 611, a circular-cutting-shaped avoiding hole 612 with a semi-circular structure is arranged on the cylindrical surface of the semi-cylinder 61, a fan-shaped gear ring 621 penetrating through the avoiding hole 612 is arranged on the outer arc surface of the arc plate 62, the two ends of the fan-shaped gear ring 621 are connected with arc guide rods 63, the other ends of the arc guide rods 63 are connected on the frame 1, the circle center of the arc is coincident with the circle center of the fan-shaped gear ring 621, return springs 64 are sleeved on the two arc guide rods 63, the two ends of the return springs are welded between the end of the fan-shaped gear ring and the frame 1, a motor fixing partition plate 65 is horizontally welded below the semi-cylinder 61 on the frame 1, a driving motor 66 is fixedly installed on the upper end surface of the motor fixing partition plate 65 through bolts, and an incomplete gear 661 meshed with the fan-shaped gear ring 621 is arranged on an output shaft of the driving motor 66.
The hollow fiber ultrafiltration membrane tubes after unloading are collected in the circular arc plate 62, and in the process of stacking and finishing in step S5, the incomplete gear 661 is driven to rotate at a constant speed by starting the driving motor 66, when the incomplete gear 661 is engaged with the sector-shaped gear ring 621, the incomplete gear 661 drives the sector-shaped gear ring 621 engaged therewith to drive the arc plate 62 to rotate along the two semicircular guide rails 611 by a certain angle, and when the incomplete gear 661 is in a non-engaged state with the sector-shaped gear ring 621, the circular arc plate 62 is urged to return to the initial equilibrium position by the elastic force of the return spring 64, which is circulated along with the rotation of the incomplete gear 661, in the repeated swinging and rotating process of the arc plate 62, the hollow fiber ultrafiltration membrane tube falling into the arc plate forms a neat stacking state for automatic arrangement, so that the arrangement process is omitted, and the later-stage centralized collection and stacking are facilitated.
Those skilled in the art will appreciate that variations may be implemented by those skilled in the art in combination with the prior art and the above-described embodiments, and will not be described in detail herein. Such variations do not affect the essence of the present invention and are not described herein.
The above description is of the preferred embodiment of the invention. It is to be understood that the invention is not limited to the particular embodiments described above, in that devices and structures not described in detail are understood to be implemented in a manner common in the art; it will be understood by those skilled in the art that various changes and modifications may be made, or equivalents may be modified, without departing from the spirit of the invention. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention, unless the contents of the technical solution of the present invention are departed.