Background
Metal 3D printing technology is one of the laser additive manufacturing technologies that has emerged in recent years. Different from the traditional machining mode of cutting and assembling raw materials, the additive manufacturing technology is a manufacturing method through material accumulation from bottom to top, and is commonly used for parts of 3D printing small aero-engines from the beginning to the end.
As in the chinese application patent No.: the invention discloses a powder feeding device of a metal 3D printer, which comprises a powder storage box, a baffle plate, a discharge hole, a first connecting rod, a second connecting rod, a transmission shaft and a servo motor, wherein the discharge hole is formed in the lower part of the powder storage box, the baffle plate is arranged in an inner cavity arranged in the powder storage box, the first connecting rod is fixedly connected to the upper part of the baffle plate, the second connecting rod is fixedly connected to the upper part of the first connecting rod, the second connecting rod is fixedly connected with the transmission shaft through a connecting plate, the transmission shaft is fixedly connected with the outer wall of the powder storage box through a bearing seat, a driven wheel is fixedly connected to the transmission shaft, and the driven wheel is meshed with a driving wheel on an output shaft of the servo motor.
However, the existing metering powder feeding device has the following problems:
1. most of the powder is single in powder feeding, manual adding is needed, and when workers cannot add the powder in time, the using effect is easily influenced, the normal printing efficiency is delayed, and unnecessary loss is caused;
2. generally, the powder feeding amount is single and cannot be adjusted according to the actual powder amount, so that powder is easily wasted and unnecessary loss is caused.
In addition, the quality requirement of important parts on aerospace equipment is very high, when powder is added, if the powder has a hollow hole, the powder can be reflected in the inner wall of a product, if the powder is not paved flatly enough, the surface of the powder has raised scattered powder, and due to the problem that laser needs to be focused, the laser cannot correctly melt metal particles, so that the product quality has fatal defects, the conventional 3D printer is not ideal in convenient control, and Chinese patent publication No. CN206997776U discloses a powder feeding and spreading device of an SLM type 3D printer, which comprises a roller, a slide rail, a powder feeding frame, a roller shaft, a powder feeding funnel, a transverse partition plate, a spring A, a support rod A, a transverse shaft, a roller shaft, a sleeve A, a support rod B, a scraper blade, a sleeve B and a spring B; the gyro wheel axle is rotatable to be installed on sending the powder frame, the gyro wheel can be followed the slide rail and made a round trip to roll, send powder funnel fixed mounting on sending the powder frame, cross slab fixed mounting is inside sending the powder funnel, send powder frame bottom both sides welded fastening respectively have sleeve A and sleeve B, wherein be equipped with spring A in the sleeve A, be equipped with spring B in the sleeve B, branch B fixed mounting is at the top of scraper blade, the cross slab in sending the powder funnel that sets up through the device has network structure, can disperse well added metal powder, prevent it excessively to pile up, the back and forth slip and the roll of scraper blade and roller, make metal powder level and smooth, but do not extrude the powder, there is the hollow condition, and, when scraper blade and roller return stroke, it drops on the powder plane of just strickleing off to have scattered powder on the roller, lead to the powder still not level.
Based on the situation, the invention provides a base shaft type metal 3D printing device which can effectively solve the problems.
Disclosure of Invention
The invention aims to provide a base shaft type metal 3D printing device. The base shaft type metal 3D printing device is simple in structure and convenient to use, automatic feeding is achieved, printing efficiency is improved, and labor intensity is reduced; and the printing effect is good, and the metal powder after printing is convenient to recycle.
The invention is realized by the following technical scheme:
a basic shaft type metal 3D printing device comprises a metering powder feeding device and a powder supplementing and scraping integrated device;
the powder inlet of the metering powder feeding device is communicated with a raw material box of the powder supplementing and scraping integrated device through a powder feeding pipe;
as a preferred technical scheme of the invention, the metering powder feeding device comprises a fixed box, a groove is arranged in the fixed box, the side surface of the fixed box is fixedly connected with a driving motor, one end of the driving motor penetrating through the fixed box is fixedly connected with a fixed threaded rod, the surface of the fixed threaded rod is rotatably connected with a movable seat through threads, the surface of the movable seat is fixedly connected with a movable frame, the side surface of the movable frame is fixedly connected with a transport box, the top of the transport box is fixedly connected with a powder adding port, the top of the fixed box is fixedly connected with a powder storage box, the interior of the powder storage box is provided with a sliding chute, the bottom of the powder storage box is fixedly connected with a powder storage outlet, the bottom of the transport box is fixedly connected with a fixed port, the bottom of the fixed box is fixedly connected with a powder supplementing box, and the top of the powder supplementing box is fixedly connected with a powder inlet, the powder supplementing box is characterized in that a powder inlet is fixedly connected to the side face of the powder supplementing box, a sliding seat is fixedly connected to the side face of the transport box, a fixed rod is slidably connected to the inside of the sliding seat, one end of the fixed rod is fixedly connected to the fixed groove, the fixed groove is formed in the fixed box, and a mounting seat is fixedly connected to the side face of the fixed box.
According to a preferred technical scheme, the powder supplementing and scraping integrated device comprises a machine body, a box door is rotatably connected to the outer wall of the machine body, a second handle is fixedly connected to the outer wall of the box door, a partition plate is fixedly connected to the inner side of the machine body, a recovery channel is formed in the inner wall of the partition plate, a second air cylinder is fixedly connected to the upper surface of the partition plate, a guide rail is fixedly connected to the inner side of the machine body, an exhaust fan is fixedly connected to the top of the machine body, a powder recovery assembly, a laser assembly, a powder supplementing and scraping assembly and a lifting assembly are arranged inside the machine body, the powder recovery assembly and the powder supplementing and scraping assembly are in sliding connection with the machine body, the laser assembly is fixedly connected with the machine body, and the lifting assembly is fixedly connected with the partition plate.
As a preferable technical solution of the present invention, a sliding cover is slidably connected to an inside of the sliding groove, and a pull groove is formed in the sliding cover.
As a preferable technical scheme of the invention, the powder storage box is internally and rotatably connected with a quantity control blade through a bearing, the top of the quantity control blade is fixedly connected with a crank, and the quantity control blade is positioned at the top of the powder storage outlet.
As a preferred technical scheme, a filter plate is fixedly connected inside the transportation box, and filter holes are formed inside the filter plate.
As a preferable technical scheme of the invention, the surface of the driving motor is fixedly connected with a motor frame, and the side surface of the motor frame is fixedly connected to the fixed box.
As a preferable technical scheme of the invention, the number of the installation seats is two, and the installation seats are internally provided with installation grooves.
As a preferred technical scheme of the invention, the powder recovery assembly comprises a drawer, the drawer is connected inside the machine body in a sliding mode, a first handle is fixedly connected to the outer wall of the drawer, and the drawer is arranged below the recovery channel.
As a preferred technical scheme of the invention, the laser assembly comprises a radiator, the radiator is fixedly connected to the top of the inner side of the machine body, the lower surface of the radiator is fixedly connected with a laser module, the lower surface of the laser module is fixedly connected with a protective mirror, and the radiator is communicated with an exhaust fan.
As a preferable technical scheme of the invention, the powder supplementing and scraping component comprises a sliding plate, the sliding plate is connected to the upper side of a guide rail in a rolling way, rollers are rotatably connected to two sides of the sliding plate, the sliding plate is connected with the guide rail in a rolling way through the rollers, a first fixed seat and a second fixed seat are fixedly connected to the lower surface of the sliding plate, a rolling shaft and a first secondary roller are rotatably connected between the first fixed seat and the second fixed seat, a second secondary roller is fixedly connected between the first fixed seat and the second fixed seat, a second motor is fixedly connected to the upper surface of the partition plate, a second belt wheel is fixedly connected to the output end of the second motor, a fourth belt wheel is fixedly connected to one end of the rolling shaft, a second belt is sleeved between the fourth belt wheel and the second belt wheel, a first gear is fixedly connected to the other end of the rolling shaft, and a second gear is fixedly connected to one end of the first secondary roller, the first gear is meshed with the second gear, the lower surface of the sliding plate is fixedly connected with a push plate, and the push plate is fixedly connected with the extending end of the second cylinder.
As a preferred technical scheme of the present invention, a raw material box is fixedly connected to an inner wall of the sliding plate, a first motor is fixedly connected to a top of the raw material box, a first belt pulley is fixedly connected to an output end of the first motor, a semicircular valve shaft is rotatably connected to the inner wall of the raw material box, one end of the semicircular valve shaft penetrates through an outer wall of the raw material box and is fixedly connected to a third belt pulley, and a first belt is sleeved between the first belt pulley and the third belt pulley.
As a preferred technical scheme, the lifting assembly comprises a printing box, the printing box is fixedly connected to the inner wall of the partition plate, a first air cylinder is fixedly connected to the interior of the printing box, a supporting plate is fixedly connected to the extending end of the first air cylinder, a supporting column is fixedly connected to the upper surface of the supporting plate, a workbench is fixedly connected to the upper end of the supporting column, and a sealing ring is fixedly connected to the outer wall of the workbench.
Compared with the prior art, the invention has the following advantages and beneficial effects:
the base shaft type metal 3D printing device is simple in structure and convenient to use, automatic feeding is achieved, printing efficiency is improved, and labor intensity is reduced; and the printing effect is good, and the metal powder after printing is convenient to recycle.
According to the metering powder feeding device, due to the arrangement of the transport box, the fixed threaded rod and the driving motor, when the metal powder is used, the metal powder is added conveniently by workers, so that the problem that the metal powder cannot be added in time due to manual adding in the prior art is solved, the use effect is easily influenced, the normal printing efficiency is delayed, and unnecessary loss is caused.
1. This measurement send whitewashed device through transport box, fixed threaded rod and driving motor, when the metal powder use finishes, makes things convenient for the staff to add to avoid because traditional artificial interpolation, unable timely interpolation that adds, thereby influence the result of use easily, delay normal printing efficiency, cause the unnecessary loss.
2. This measurement powder feeding device, through accuse volume leaf and crank, make things convenient for the staff to control the volume of advancing of metal powder, produce the unnecessary waste when avoiding using, cause the unnecessary loss.
The powder supplementing and scraping integrated device provided by the invention can be used for extruding powder by rolling between the rolling shaft and the first auxiliary roller after the powder is put in, so that the powder is more compact, the semicircular valve shaft can conveniently open and close the raw material box, and the powder adhered to the rolling shaft in the return stroke can be scraped by the second auxiliary roller extruded together with the rolling shaft through the second auxiliary roller which is arranged above the rolling shaft, so that scattered powder is prevented from falling in the rolled area.
Compared with the prior art, this mend powder and scrape integrative device of powder, through setting up raw material tank above roller bearing and first pair roller, the powder is put in the back and is extruded through the roll between roller bearing and the first pair roller, makes the powder compacter, through the semicircle valve spindle that sets up on the raw material tank, under the drive of first motor, can be convenient open and close raw material tank, avoid continuously throwing the material and cause frequently reinforced. Through the second auxiliary roller which is arranged above the roller and does not rotate, the roller rolls clockwise on the metal powder plane of the workbench during return stroke, redundant powder is swept to the recovery channel, powder stuck on the roller can be scraped by the second auxiliary roller which is extruded together with the roller, and the condition that scattered powder does not fall in the rolled area is ensured.
Detailed Description
In order that those skilled in the art will better understand the technical solutions of the present invention, the following description of the preferred embodiments of the present invention is provided in conjunction with specific examples, but it should be understood that the drawings are for illustrative purposes only and should not be construed as limiting the patent; for the purpose of better illustrating the present embodiments, certain elements of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted. The positional relationships depicted in the drawings are for illustrative purposes only and are not to be construed as limiting the present patent.
Example 1:
as shown in fig. 1 to 14, a base shaft type metal 3D printing device comprises a metering powder feeding device and a powder supplementing and scraping integrated device;
the powder inlet of the metering powder feeding device is communicated with a raw material box of the powder supplementing and scraping integrated device through a powder feeding pipe;
the metering powder feeding device comprises a fixed box, a groove is formed in the fixed box, a driving motor is fixedly connected to the side face of the fixed box, the driving motor penetrates through one end of the fixed box and is fixedly connected with a fixed threaded rod, the surface of the fixed threaded rod is rotatably connected with a movable seat through threads, the surface of the movable seat is fixedly connected with a movable frame, the side face of the movable frame is fixedly connected with a transport box, the top of the transport box is fixedly connected with a powder adding opening, the top of the fixed box is fixedly connected with a powder storage box, a sliding groove is formed in the powder storage box, the bottom of the powder storage box is fixedly connected with a powder storage outlet, the bottom of the transport box is fixedly connected with a fixed opening, the bottom of the fixed box is fixedly connected with a powder supplementing box, the top of the powder supplementing box is fixedly connected with a powder supplementing inlet, and the side face of the powder supplementing box is fixedly connected with a powder inlet, the side fixedly connected with sliding seat of transportation box, the inside sliding connection of sliding seat has the dead lever, the one end fixed connection of dead lever is on the fixed slot, the fixed slot is seted up on fixed case, the side fixedly connected with mount pad of fixed case.
Mend powder and scrape integrative device of powder and include the fuselage, the fuselage outer wall rotates and is connected with the chamber door, chamber door outer wall fixedly connected with second handle, the inboard fixedly connected with baffle of fuselage, recovery channel has been seted up to the baffle inner wall, fixed surface is connected with the second cylinder on the baffle, the inboard fixedly connected with guide rail of fuselage, fuselage top fixedly connected with exhaust fan, inside powder recovery subassembly, the laser unit spare, the powder scraping subassembly, the lifting unit of being provided with of fuselage, powder recovery subassembly, powder scraping subassembly and fuselage sliding connection are mended to the powder, laser unit spare and fuselage fixed connection, lifting unit and baffle fixed connection.
Example 2:
as shown in fig. 1 to 14, a base shaft type metal 3D printing device comprises a metering powder feeding device and a powder supplementing and scraping integrated device;
the powder inlet of the metering powder feeding device is communicated with a raw material box of the powder supplementing and scraping integrated device through a powder feeding pipe;
in practical application, a vacuum conveyor can be additionally arranged on the powder feeding pipe according to requirements;
referring to fig. 2-5, the metering powder feeding device of the present invention comprises a fixed box, a groove is formed inside the fixed box, a driving motor is fixedly connected to a side surface of the fixed box, one end of the driving motor penetrating through the fixed box is fixedly connected with a fixed threaded rod, the surface of the fixed threaded rod is rotatably connected with a movable seat through a thread, the surface of the movable seat is fixedly connected with a movable frame, a transportation box is fixedly connected to a side surface of the movable frame, the top of the transportation box is fixedly connected with a powder adding port, the top of the fixed box is fixedly connected with a powder storage box, a chute is formed inside the powder storage box, the bottom of the powder storage box is fixedly connected with a powder storage outlet, the bottom of the transportation box is fixedly connected with a fixed port, the bottom of the fixed box is fixedly connected with a powder supplementing box, the top of the powder supplementing box is fixedly connected with a powder inlet, the side surface of the powder supplementing box is fixedly connected with a powder inlet, and the side surface of the transportation box is fixedly connected with a sliding seat, the inside sliding connection of sliding seat has the dead lever, and the one end fixed connection of dead lever is on the fixed slot, and the fixed slot is seted up on fixed case, the side fixedly connected with mount pad of fixed case.
In this embodiment, through the removal seat that the screw thread rotation is connected on fixed thread rod surface, remove the removal frame that seat fixed surface connects, remove a side fixed connection's transport box, transport box top fixed connection's the powder mouth that adds makes things convenient for the staff to add, avoids because the interpolation is untimely, leads to influencing normal use.
Referring to fig. 6-14, the powder supplementing and scraping integrated device of the invention comprises: including the fuselage, the fuselage outer wall rotates and is connected with the chamber door, chamber door outer wall fixedly connected with second handle, the inboard fixedly connected with baffle of fuselage, the recovery passageway has been seted up to the baffle inner wall, fixed surface is connected with the second cylinder on the baffle, the inboard fixedly connected with guide rail of fuselage, fuselage top fixedly connected with exhaust fan, the inside powder recovery subassembly that is provided with of fuselage, laser assembly, mend the powder and scrape whitewashed subassembly, lifting unit, the powder recovery subassembly, mend the powder and scrape whitewashed subassembly and fuselage sliding connection, laser assembly and fuselage fixed connection, lifting unit and baffle fixed connection.
Specifically, the inside sliding connection of spout has the sliding closure, and the kerve has been seted up to the inside of sliding closure.
In this embodiment, through the inside kerve of seting up of sliding cover, make things convenient for the staff to take sliding cover out from the spout, facilitate the use.
Specifically, the inside of the powder storage box is rotatably connected with a quantity control blade through a bearing, the top of the quantity control blade is fixedly connected with a crank, and the quantity control blade is positioned at the top of the powder storage outlet.
In this embodiment, lie in storage powder export top through accuse volume leaf, make things convenient for the staff to control the volume of advancing of metal powder, facilitate the use.
Specifically, the inside fixedly connected with filter of transport box, the filtration pore has been seted up to the inside of filter.
In this embodiment, through the inside filtration pore of seting up of filter, filter the metal powder that uses, avoid getting into the foreign matter, influence normal use.
Specifically, driving motor's fixed surface is connected with the motor frame, and the side fixed connection of motor frame is on fixed case.
In this embodiment, through the motor frame of driving motor fixed surface connection, carry out the guard action to driving motor, avoid taking place to damage.
Specifically, the quantity of mount pad is two, and the mounting groove has been seted up to the inside of mount pad.
In this embodiment, through the inside mounting groove of seting up of mount pad, make things convenient for the staff to install and use, make it more stable.
The working principle and the using process of the metering powder feeding device are as follows:
when the metal powder replenishing box is used, a worker pulls the pull groove to draw the sliding cover out of the sliding groove, metal powder to be used is added into the powder storing box, the crank is pulled to drive the quantity control blade to start rotating, the position of the rotating quantity control blade is changed, so that the quantity of the metal powder entering the powder storing outlet is conveniently adjusted, when the metal powder in the powder replenishing box is used, the driving motor is arranged to start to drive the driving motor to pass through the fixed threaded rod fixedly connected with the output end of the fixed box to start rotating, the surface of the rotating fixed threaded rod drives the moving seat through threaded connection, the moving seat drives the moving frame fixedly connected with the surface to start moving, the moving frame drives the transport box to start moving, the transport box is moved to the lower part of the powder storing box, and the metal powder enters the inside of the metal powder adding outlet from the powder storing outlet, the metal powder is filtered by the filter hole, so that foreign matters are prevented from entering the powder replenishing box to affect use, the movable transport box is arranged above the powder replenishing box, the metal powder in the transport box enters the powder replenishing inlet through the fixing port, and enters the raw material box (powder supply) of the metering powder feeding device through the powder inlet through the powder feeding pipe to be printed, so that the powder replenishing box is convenient to use, and the position of the transport box is limited by arranging the sliding seat to slide on the surface of the fixing rod.
Specifically, the powder recycling assembly comprises a drawer, the drawer is slidably connected inside the machine body, a first handle is fixedly connected to the outer wall of the drawer, the drawer is arranged below the recycling channel, redundant powder drops into the drawer through the recycling channel, and the powder is conveniently recycled.
Specifically, the laser assembly comprises a radiator, the radiator is fixedly connected to the top of the inner side of the machine body, the laser module is fixedly connected to the lower surface of the radiator, a protective mirror is fixedly connected to the lower surface of the laser module, the radiator is communicated with the exhaust fan, the exhaust fan can remove heat emitted by the laser assembly during operation, and damage to equipment due to overheating is avoided.
Specifically, the powder supplementing and scraping assembly comprises a sliding plate, the sliding plate is connected to the upper side of a guide rail in a rolling manner, rollers are rotatably connected to two sides of the sliding plate, the sliding plate is connected with the guide rail in a rolling manner through the rollers, a first fixed seat and a second fixed seat are fixedly connected to the lower surface of the sliding plate, a rolling shaft and a first auxiliary roller are rotatably connected between the first fixed seat and the second fixed seat, a second auxiliary roller is fixedly connected between the first fixed seat and the second fixed seat, a second motor is fixedly connected to the upper surface of a partition plate, a second belt wheel is fixedly connected to the output end of the second motor, one end of the rolling shaft is fixedly connected with a fourth belt wheel, a second belt is sleeved between the fourth belt wheel and the second belt wheel, a first gear is fixedly connected to the other end of the rolling shaft, a second gear is fixedly connected to one end of the first auxiliary roller, the first gear is meshed with the second gear, a push plate is fixedly connected to the lower surface of the sliding plate, and the push plate is fixedly connected with the extending end of a second air cylinder, promote the push pedal through the second cylinder, drive the sliding plate and carry out the back-and-forth movement, realize mending the powder and scrape the function of powder, the vice roller of second is non-rotating, and all the other roller bearings in close contact with play the effect of scraping the powder when the return stroke.
Concretely, sliding plate inner wall fixedly connected with raw material tank, the first motor of raw material tank top fixedly connected with, the first band pulley of first motor output fixedly connected with, the raw material tank inner wall rotates and is connected with semicircle valve shaft, semicircle valve shaft one end runs through raw material tank outer wall and fixedly connected with third band pulley, the cover is equipped with first belt between first band pulley and the third band pulley, the raw material tank export sets up between roller bearing and first secondary roller, throw the material accuracy, through semicircle valve shaft, can be accurate when need not throw the material close the raw material tank.
Specifically, lifting unit includes the printing box, and printing box fixed connection is at the baffle inner wall, the first cylinder of the inside fixedly connected with of printing box, and first cylinder stretches out fixedly connected with backup pad, and fixed surface is connected with the support column in the backup pad, support column upper end fixedly connected with workstation, workstation outer wall fixedly connected with sealing washer, and first cylinder drives the action of progressively moving down of workstation.
The working principle of the powder supplementing and scraping integrated device is as follows:
the second cylinder drives the powder supplementing and scraping component to move forwards, the second motor drives the rolling shaft and the first auxiliary roller to rotate, the first motor drives the semicircular valve shaft to rotate, the raw material box is opened, metal powder enters the rolling shaft between the first auxiliary roller from the outlet at the lower end of the raw material box and is extruded by the first auxiliary roller and the rolling shaft and then laid on the workbench, the powder is compact, and no cavity exists;
the metal powder is fully paved on the workbench through the extension of the second cylinder, the first motor drives the semicircular valve shaft to rotate, the raw material box is closed, the metal powder is not put in, the second cylinder retracts to drive the powder supplementing and scraping component to move backwards, the roller shaft sweeps away redundant powder backwards, the metal powder adhered on the roller shaft is scraped by the second auxiliary roller and cannot fall on a rolled area, after the retraction of the second cylinder is completed, the laser component works, after the work of the laser component is completed, the first cylinder drives the workbench to move downwards by one layer, the actions are repeated until the product is printed,
the redundant powder enters the drawer through the recovery channel to be recovered;
the raw material box is arranged above the rolling shaft and the first auxiliary roller, and the powder is extruded by rolling between the rolling shaft and the first auxiliary roller after being put in, so that the powder is more compact;
through the semicircle valve shaft that sets up on the raw material tank, under the drive of first motor, can be convenient open and close the raw material tank, avoid continuously throwing the material and cause frequently reinforced.
Through the second auxiliary roller which is arranged above the roller and does not rotate, during return stroke, the roller rolls clockwise on the metal powder plane of the workbench, redundant powder is swept to the recycling channel, the powder stuck on the roller can be scraped by the second auxiliary roller which is in close contact with the roller, and the condition that scattered powder does not fall in the rolled area is ensured.
According to the description and the drawings of the invention, the basic shaft type metal 3D printing device can be easily manufactured or used by a person skilled in the art, and the positive effects recorded by the invention can be generated.
Unless otherwise specified, in the present invention, if there is an orientation or positional relationship indicated by terms of "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., based on the orientation or positional relationship shown in the drawings, it is only for convenience of describing the present invention and simplifying the description, rather than to indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore, the terms describing orientation or positional relationship in the present invention are used for illustrative purposes only, and should not be construed as limiting the present patent, specific meanings of the above terms can be understood by those of ordinary skill in the art in light of the specific circumstances in conjunction with the accompanying drawings.
Unless expressly stated or limited otherwise, the terms "disposed," "connected," and "connected" are to be construed broadly and encompass, for example, being fixedly connected, detachably connected, or integrally connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and all simple modifications and equivalent variations of the above embodiments according to the technical spirit of the present invention are included in the scope of the present invention.