阅读说明：本技术 一种挤出型rtp复合压力管件的加工工艺 (Processing technology of extrusion type RTP composite pressure pipe fitting ) 是由 刘俊峰 刘文江 万刚 王�华 于 2021-08-10 设计创作，主要内容包括：本发明公开一种挤出型RTP复合压力管件的加工工艺,包括以下步骤：步骤一、挤出RTP复合压力管材：将PE材料通过负压的方式送入挤出机中,并对PE材料进行加热,然后将管材内层挤出,本发明通过先将电阻丝以螺旋缠绕的方式缠绕在热熔设备中加热筒的外表面,并在滴胶道上滴加热熔胶,使得螺旋缠绕的电阻丝进行定型,从而形成电阻丝嵌件,然后通过热熔设备将电阻丝嵌件放入管件的内部,再通过热熔的方式将电阻丝嵌件与管件的内部进行粘接,等待热熔胶冷却即可,通过该种事先将电阻丝定型的方式,方便将电阻丝嵌件送入管件的内部,无须顾及电阻丝的柔软程度,然后通过热熔的方式将其进行固定,不仅操作较为简单,而且速度较快。(The invention discloses a processing technology of an extrusion type RTP composite pressure pipe fitting, which comprises the following steps: step one, extruding an RTP composite pressure pipe: the PE material is fed into the extruder in a negative pressure mode, the PE material is heated, and then the inner layer of the pipe is extruded, the resistance wire is wound on the outer surface of a heating cylinder in hot melting equipment in a spiral winding mode firstly, hot melt adhesive is dripped on a glue dripping channel, the spiral winding resistance wire is shaped, so that a resistance wire insert is formed, the resistance wire insert is placed into the pipe fitting through the hot melting equipment, the resistance wire insert is bonded with the inside of the pipe fitting in the hot melting mode, the hot melt adhesive is waited to be cooled, the resistance wire is shaped in advance, the resistance wire insert is conveniently fed into the inside of the pipe fitting, the softness degree of the resistance wire does not need to be considered, and then the resistance wire insert is fixed in the hot melting mode, the operation is simple, and the speed is high.)

1. The processing technology of the extrusion type RTP composite pressure pipe fitting is characterized by comprising the following steps of:

step one, extruding an RTP composite pressure pipe: feeding a PE material into an extruder in a negative pressure mode, heating the PE material, extruding the inner layer of the pipe, winding a reinforcing belt on the inner layer of the pipe at the moment with constant tension to form a reinforcing layer, co-extruding the inner layer and the outer layer of the pipe, sizing after extrusion, and then spraying, cooling and forming;

step two, shaping and cutting: cutting the formed pipe into pipe fittings with fixed length;

step three, prefabricating resistance wire inserts: winding the resistance heating wire on hot melting equipment in a spiral mode, then coating a layer of hot melt adhesive on the outer surface of the resistance heating wire, and taking the resistance heating wire out of the surface of the shaping pipe after the hot melt adhesive is cooled, so as to obtain a resistance wire insert;

step four, installing resistance wire inserts: the resistance wire insert is arranged on the inner surface of the pipe fitting in a hot melting mode through hot melting equipment.

2. The process of claim 1, wherein the PE material is HDPE.

3. The processing technology of the extruded RTP composite pressure pipe fitting as recited in claim 1, wherein the reinforcing tape is formed by stranding fiber filaments, and the reinforcing tape is wound on the surface of the inner pipe at an inclination angle of 50-55 degrees.

4. The process as claimed in claim 1, wherein the PE material is heated at a temperature of 150-220 ℃.

5. The process of claim 1, wherein the screw extruding speed of the inner layer of the tube is 60-80 r/min.

6. The process of claim 1, wherein the diameter of the resistance wire insert is less than the inner diameter of the tube.

7. The process of claim 1, wherein the hot-melt apparatus is used by the method comprising: firstly, the electric heating wire is wound on the outer surface of a heating cylinder (4) in a spiral mode, then hot melt adhesive is dripped at a glue dripping channel (5), the hot melt adhesive on the surface of the electric heating wire is solidified, so that a resistance wire insert is formed, meanwhile, a pipe fitting is sent into the fixed cylinder (2), a top block (19) is pushed out from the inside of a rotating sleeve (16) by rotating a limiting bolt (18) and is contacted with the outer surface of the pipe fitting, so that the pipe fitting is fixed in the fixed cylinder (2) and is fully contacted with a heating ring (20), at the moment, a driving motor (6) is started, the driving motor (6) drives a threaded rod (8) to rotate, so that a support plate (3) slides above a support frame (1), a sliding rod (10) slides in a through hole (9), and the resistance wire insert on the heating cylinder (4) is further inserted into the pipe fitting, then be connected cartridge heater (4) and heating collar (20) with external power supply, thereby make cartridge heater (4) and heating collar (20) heat the hot melt adhesive on pipe fitting and resistance wire inserts surface, start rotating motor (12) this moment, make rotating gear (13) rotate, thereby the internal surface that drives cartridge heater (4) at rotating sleeve (16) through rotating gear (13) and the meshing relation of ring gear (14) rotates, paint the internal surface at the pipe fitting evenly with the hot melt adhesive through dripping gluey way (5), wait for the hot melt adhesive cooling shaping after, take out the pipe fitting can.

Technical Field

The invention relates to the technical field of composite pressure pipe fittings, in particular to a processing technology of an extrusion type RTP composite pressure pipe fitting.

Background

The pipe plays an important role in conveying the medium, however, pure steel pipes and pure plastic pipes have unsatisfactory places, the former is affected by corrosion, and the latter is insufficient in strength and pressure-bearing capacity, so that the composite pipe becomes two points of research, reinforced thermoplastic composite pipes (RTP) are one of the two, and the electric melting pipe fittings need to have certain resistance to corrosion and certain bearing pressure.

At present, the RTP composite pressure pipe fitting is extruded and formed, a resistance wire needs to be placed into the pipe fitting subsequently, and the resistance wire is relatively soft and the diameter of the pipe is relatively small, so that the speed is relatively low and the operation is relatively troublesome when the pipe fitting is prepared.

Disclosure of Invention

The invention aims to provide a processing technology of an extrusion type RTP composite pressure pipe fitting.

The purpose of the invention can be realized by the following technical scheme: a processing technology of an extrusion type RTP composite pressure pipe fitting comprises the following steps:

step one, extruding an RTP composite pressure pipe: feeding a PE material into an extruder in a negative pressure mode, heating the PE material, extruding the inner layer of the pipe, winding a reinforcing belt on the inner layer of the pipe at the moment with constant tension to form a reinforcing layer, co-extruding the inner layer and the outer layer of the pipe, sizing after extrusion, and then spraying, cooling and forming;

step two, shaping and cutting: cutting the formed pipe into pipe fittings with fixed length;

step three, prefabricating resistance wire inserts: winding the resistance heating wire on hot melting equipment in a spiral mode, then coating a layer of hot melt adhesive on the outer surface of the resistance heating wire, and taking the resistance heating wire out of the surface of the shaping pipe after the hot melt adhesive is cooled, so as to obtain a resistance wire insert;

step four, mounting the resistance wire insert: the resistance wire insert is arranged on the inner surface of the pipe fitting in a hot melting mode through hot melting equipment.

In a further aspect of the present invention, the PE material is high density polyethylene HDPE.

As a further scheme of the invention, the reinforcing tape is formed by plying and weaving fiber yarns, and the reinforcing tape is wound on the surface of the inner-layer pipe at an inclination angle of 50-55 degrees.

As a further scheme of the invention, the heating temperature of the PE material is 150-220 ℃.

As a further scheme of the invention, the rotating speed of the screw extrusion of the inner layer of the pipe fitting is 60-80 r/min.

As a further scheme of the invention, the diameter of the resistance wire insert is smaller than the inner diameter of the pipe fitting.

As a further scheme of the invention, the hot melting equipment comprises a support frame, wherein a placing groove is formed in one side of the top of the support frame, a fixed cylinder is fixedly connected inside the placing groove, a support plate is arranged on the other side of the top of the support frame, a rotating groove is formed in the support plate, an object placing groove is fixedly connected to the inner surface of the rotating groove, a heating cylinder is rotatably connected to the inner surface of the object placing groove, a plurality of glue dripping channels are formed in the outer surface of the heating cylinder, a threaded sleeve is arranged on one side of the support plate in a penetrating manner, a threaded rod is connected to the inner surface of the threaded sleeve in a threaded manner, a fixed plate is fixedly connected to one side of the top of the support frame and positioned on the right side of the support plate, a driving motor is fixedly connected to one side of the fixed plate, and the output end of the driving motor is fixedly connected with one end of the threaded rod;

through holes are formed in one side of the supporting plate and located on the front side and the rear side of the threaded sleeve, sliding rods are connected to the inner surfaces of the through holes in a sliding mode, one end of each through hole is fixedly connected with one side of the supporting frame, and the other end of each through hole is fixedly connected with one side of the fixing plate;

the front surface of the supporting plate is provided with a rotating motor, the output end of the rotating motor is fixedly connected with a rotating gear, the outer surface of the heating cylinder is provided with a gear ring, and the outer surface of the rotating gear is meshed with the outer surface of the gear ring;

the internal surface of a fixed section of thick bamboo is provided with the heating collar, the surface of a fixed section of thick bamboo is provided with a plurality of stopper, the top threaded connection of stopper has spacing bolt, the bottom of spacing bolt is rotated and is connected with the kicking block, the bottom of stopper has been seted up and has been put the thing groove.

As a further scheme of the invention, the use method of the hot melting equipment comprises the following steps: firstly, the heating wire is wound on the outer surface of the heating cylinder in a spiral mode, then hot melt adhesive is dripped at the position of the adhesive dripping channel, so that the hot melt adhesive on the surface of the heating wire is solidified, thereby forming a resistance wire insert, meanwhile, the pipe fitting is sent into the inside of the fixed cylinder, the top block is pushed out from the inside of the object placing groove by rotating the limiting bolt and is contacted with the outer surface of the pipe fitting, thereby fixing the pipe fitting in the inside of the fixed cylinder and being fully contacted with the heating ring, at the moment, the driving motor is started, the driving motor drives the threaded rod to rotate, thereby enabling the supporting plate to slide above the supporting frame, and the sliding rod slides in the through hole, further enabling the resistance wire insert on the heating cylinder to be inserted in the pipe fitting, then the heating cylinder and the heating ring are connected with an external power supply, thereby enabling the heating cylinder and the heating ring to heat the hot melt adhesive on the surfaces of the pipe fitting and the resistance wire insert, the motor is rotated in the start-up this moment for rotating gear rotates, thereby drives the cartridge heater and rotate at the internal surface of putting the thing groove through the meshing relation of rotating gear and ring gear, through dripping the gluey way with even the scribbling of hot melt adhesive at the internal surface of pipe fitting, wait for the hot melt adhesive cooling shaping after, take out the pipe fitting can.

The invention has the beneficial effects that:

(1) according to the processing technology of the extrusion type RTP composite pressure pipe fitting, the resistance wire is wound on the outer surface of the heating cylinder in the hot melting equipment in a spiral winding mode, the hot melt adhesive is dripped on the adhesive dripping channel, so that the spiral wound resistance wire is shaped to form the resistance wire insert, the resistance wire insert is placed into the pipe fitting through the hot melting equipment, the resistance wire insert is bonded with the inside of the pipe fitting through the hot melting mode, the hot melt adhesive is cooled, the resistance wire insert is conveniently fed into the inside of the pipe fitting through the mode of shaping the resistance wire in advance, the softness degree of the resistance wire is not needed to be considered, and the resistance wire insert is fixed through the hot melting mode.

(2) The invention relates to a processing technology of an extrusion type RTP composite pressure pipe fitting, which can realize that a heating cylinder on a supporting plate is conveyed into the interior of the pipe fitting by arranging a driving motor in a hot melting device to drive a threaded rod to rotate, can improve the stability of the supporting plate during movement by arranging two sliding rods, is provided with a glue dripping channel outside the heating cylinder to drip hot melt glue at the position of the glue dripping channel, can ensure that the height of the hot melt glue is not higher than that of the heating cylinder, so that the hot melt glue can be completely inserted into the interior of the pipe fitting, a limit bolt on a limit block can enable a top block to be inserted into and prop against the outer wall of the pipe fitting by rotating the limit bolt, so that the pipe fitting is limited, and the rotating motor is arranged to drive a gear ring to rotate through a rotating gear, so as to drive the heating cylinder to rotate, and redundant hot melt glue can be uniformly coated on the surface of a resistance wire insert through the glue dripping channel, thereby the stable inside of fixing at the pipe fitting of resistance wire inserts that makes, solve the problem that the resistance wire inserts is difficult to fix the inner wall at the pipe fitting through this structure.

Drawings

The invention will be further described with reference to the accompanying drawings.

FIG. 1 is a schematic flow diagram of a process for manufacturing an extruded RTP composite pressure pipe of the present invention;

FIG. 2 is a schematic view of the external structure of the heat-fusible device in the present invention;

FIG. 3 is a side view of the structure of the exterior of the support plate of the present invention;

fig. 4 is a side view showing an outer structure of the fixed cylinder in the present invention.

In the figure: 1. a support frame; 2. a fixed cylinder; 3. a support plate; 4. a heating cylinder; 5. a glue dripping channel; 6. a drive motor; 7. a threaded sleeve; 8. a threaded rod; 9. a through hole; 10. a slide bar; 11. a fixing plate; 12. rotating the motor; 13. a rotating gear; 14. a ring gear; 15. a rotating groove; 16. rotating the sleeve; 17. a limiting block; 18. a limit bolt; 19. a top block; 20. and (4) heating the ring.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-4, the following two embodiments are provided:

example 1

The invention relates to a processing technology of an extrusion type RTP composite pressure pipe fitting, which comprises the following steps:

step one, extruding an RTP composite pressure pipe: feeding a PE material into an extruder in a negative pressure mode, heating the PE material, extruding the inner layer of the pipe, winding a reinforcing belt on the inner layer of the pipe at the moment with constant tension to form a reinforcing layer, co-extruding the inner layer and the outer layer of the pipe, sizing after extrusion, and then spraying, cooling and forming;

step two, shaping and cutting: cutting the formed pipe into pipe fittings with fixed length;

step three, prefabricating resistance wire inserts: winding the resistance heating wire on hot melting equipment in a spiral mode, then coating a layer of hot melt adhesive on the outer surface of the resistance heating wire, and taking the resistance heating wire out of the surface of the shaping pipe after the hot melt adhesive is cooled, so as to obtain a resistance wire insert;

step four, mounting the resistance wire insert: the resistance wire insert is arranged on the inner surface of the pipe fitting in a hot melting mode through hot melting equipment.

In the invention, the PE material is high density polyethylene HDPE.

According to the invention, the reinforcing belt is formed by stranding fiber yarns, and is wound on the surface of the inner-layer pipe at an inclination angle of 55 degrees.

In the invention, the heating temperature of the PE material is 220 ℃.

In the invention, the rotating speed of the screw extrusion of the inner layer of the pipe fitting is 80 r/min.

In the invention, the diameter of the resistance wire insert is smaller than the inner diameter of the pipe fitting.

In the invention, the hot melting equipment comprises a support frame 1, a placing groove is formed in one side of the top of the support frame 1, a fixed cylinder 2 is fixedly connected in the placing groove, a support plate 3 is arranged on the other side of the top of the support frame 1, a rotating groove 15 is formed in the support plate 3, the rotating groove 15 is used for placing a rotating sleeve 16, the rotating sleeve 16 is fixedly connected to the inner surface of the rotating groove 15, a heating cylinder 4 is rotatably connected to the inner surface of the rotating sleeve 16, the heating cylinder 4 is connected with an external power supply, so that the surface of the heating cylinder 4 generates heat capable of melting hot melt adhesive, a plurality of glue dripping channels 5 are formed in the outer surface of the heating cylinder 4, the glue dripping channels 5 can uniformly smear the hot melt adhesive, a threaded sleeve 7 penetrates through one side of the support plate 3, and a threaded rod 8 is connected to the inner surface of the threaded sleeve 7 in a threaded manner, a fixing plate 11 is fixedly connected to one side of the top of the support frame 1 and the right side of the support plate 3, a driving motor 6 is fixedly connected to one side of the fixing plate 11, and the output end of the driving motor 6 is fixedly connected with one end of a threaded rod 8;

through holes 9 are formed in one side of the supporting plate 3 and the front side and the rear side of the threaded sleeve 7, sliding rods 10 are connected to the inner surface of the through holes 9 in a sliding mode, the sliding rods 10 are arranged, the stability of the supporting plate 3 during moving can be improved, one end of each through hole 9 is fixedly connected with one side of the supporting frame 1, and the other end of each through hole 9 is fixedly connected with one side of the fixing plate 11;

the front surface of the supporting plate 3 is provided with a rotating motor 12, the output end of the rotating motor 12 is fixedly connected with a rotating gear 13, the outer surface of the heating cylinder 4 is provided with a gear ring 14, the outer surface of the rotating gear 13 is meshed with the outer surface of the gear ring 14, and the heating cylinder 4 can rotate through the meshing of the rotating gear 13 and the gear ring 14, so that the hot melt adhesive in the adhesive dripping channel 5 can be poured out and uniformly coated on the surface of the resistance wire insert;

the internal surface of a fixed section of thick bamboo 2 is provided with heating ring 20, the surface of a fixed section of thick bamboo 2 is provided with a plurality of stopper 17, the top threaded connection of stopper 17 has stop bolt 18, stop bolt 18's bottom is rotated and is connected with kicking block 19, rotation cover 16 has been seted up to stop 17's bottom.

In the invention, the use method of the hot melting equipment comprises the following steps: firstly, the electric heating wire is wound on the outer surface of the heating cylinder 4 in a spiral mode, then hot melt adhesive is dripped at the position of the adhesive dripping channel 5, so that the hot melt adhesive on the surface of the electric heating wire is solidified, and a resistance wire insert is formed, meanwhile, the pipe fitting is sent into the fixed cylinder 2, the top block 19 is pushed out from the inside of the rotating sleeve 16 by rotating the limiting bolt 18 and contacts with the outer surface of the pipe fitting, so that the pipe fitting is fixed in the fixed cylinder 2 and fully contacts with the heating ring 20, the driving motor 6 is started at the moment, the driving motor 6 drives the threaded rod 8 to rotate, so that the support plate 3 slides above the support frame 1, the sliding rod 10 slides in the through hole 9, the resistance wire insert on the heating cylinder 4 is further inserted into the pipe fitting, and then the heating cylinder 4 and the heating ring 20 are connected with an external power supply, thereby make cartridge heater 4 and heating collar 20 heat the hot melt adhesive on pipe fitting and resistance wire inserts surface, start rotating motor 12 this moment, make rotating gear 13 rotate, thereby drive cartridge heater 4 and rotate at the internal surface of rotating sleeve 16 through the meshing relation of rotating gear 13 with ring gear 14, through dripping gluey way 5 with the even internal surface of paining at the pipe fitting of hot melt adhesive, wait for the hot melt adhesive cooling shaping after, take out the pipe fitting can.

Example 2

The invention relates to a processing technology of an extrusion type RTP composite pressure pipe fitting, which comprises the following steps:

step one, extruding an RTP composite pressure pipe: feeding a PE material into an extruder in a negative pressure mode, heating the PE material, extruding the inner layer of the pipe, winding a reinforcing belt on the inner layer of the pipe at the moment with constant tension to form a reinforcing layer, co-extruding the inner layer and the outer layer of the pipe, sizing after extrusion, and then spraying, cooling and forming;

step two, shaping and cutting: cutting the formed pipe into pipe fittings with fixed length;

step three, prefabricating resistance wire inserts: winding the resistance heating wire on hot melting equipment in a spiral mode, then coating a layer of hot melt adhesive on the outer surface of the resistance heating wire, and taking the resistance heating wire out of the surface of the shaping pipe after the hot melt adhesive is cooled, so as to obtain a resistance wire insert;

step four, mounting the resistance wire insert: the resistance wire insert is arranged on the inner surface of the pipe fitting in a hot melting mode through hot melting equipment.

In the invention, the PE material is high density polyethylene HDPE.

According to the invention, the reinforcing belt is formed by stranding fiber yarns, and is wound on the surface of the inner-layer pipe at an inclination angle of 50 degrees.

In the invention, the heating temperature of the PE material is 150 ℃.

In the invention, the rotating speed of the screw extrusion of the inner layer of the pipe fitting is 60 r/min.

In the invention, the diameter of the resistance wire insert is smaller than the inner diameter of the pipe fitting.

In the invention, the hot melting equipment comprises a support frame 1, a placing groove is formed in one side of the top of the support frame 1, a fixed cylinder 2 is fixedly connected in the placing groove, a support plate 3 is arranged on the other side of the top of the support frame 1, a rotating groove 15 is formed in the support plate 3, the rotating groove 15 is used for placing a rotating sleeve 16, the rotating sleeve 16 is fixedly connected to the inner surface of the rotating groove 15, a heating cylinder 4 is rotatably connected to the inner surface of the rotating sleeve 16, the heating cylinder 4 is connected with an external power supply, so that the surface of the heating cylinder 4 generates heat capable of melting hot melt adhesive, a plurality of glue dripping channels 5 are formed in the outer surface of the heating cylinder 4, the glue dripping channels 5 can uniformly smear the hot melt adhesive, a threaded sleeve 7 penetrates through one side of the support plate 3, and a threaded rod 8 is connected to the inner surface of the threaded sleeve 7 in a threaded manner, a fixing plate 11 is fixedly connected to one side of the top of the support frame 1 and the right side of the support plate 3, a driving motor 6 is fixedly connected to one side of the fixing plate 11, and the output end of the driving motor 6 is fixedly connected with one end of a threaded rod 8;

through holes 9 are formed in one side of the supporting plate 3 and the front side and the rear side of the threaded sleeve 7, sliding rods 10 are connected to the inner surface of the through holes 9 in a sliding mode, the sliding rods 10 are arranged, the stability of the supporting plate 3 during moving can be improved, one end of each through hole 9 is fixedly connected with one side of the supporting frame 1, and the other end of each through hole 9 is fixedly connected with one side of the fixing plate 11;

the front surface of the supporting plate 3 is provided with a rotating motor 12, the output end of the rotating motor 12 is fixedly connected with a rotating gear 13, the outer surface of the heating cylinder 4 is provided with a gear ring 14, the outer surface of the rotating gear 13 is meshed with the outer surface of the gear ring 14, and the heating cylinder 4 can rotate through the meshing of the rotating gear 13 and the gear ring 14, so that the hot melt adhesive in the adhesive dripping channel 5 can be poured out and uniformly coated on the surface of the resistance wire insert;

the internal surface of a fixed section of thick bamboo 2 is provided with heating ring 20, the surface of a fixed section of thick bamboo 2 is provided with a plurality of stopper 17, the top threaded connection of stopper 17 has stop bolt 18, stop bolt 18's bottom is rotated and is connected with kicking block 19, rotation cover 16 has been seted up to stop 17's bottom.

In the invention, the use method of the hot melting equipment comprises the following steps: firstly, the heating wire is wound on the outer surface of the heating cylinder 4 in a spiral mode, then hot melt adhesive is dripped at the position of the adhesive dripping channel 5, so that the hot melt adhesive on the surface of the heating wire is solidified, thereby forming a resistance wire insert, meanwhile, the pipe fitting is sent into the fixed cylinder 2, the top block 19 is pushed out from the inner part of the rotating sleeve 16 by rotating the limiting bolt 18 and is contacted with the outer surface of the pipe fitting, thereby the pipe fitting is fixed in the fixed cylinder 2 and is fully contacted with the heating ring 20, the driving motor 6 is started at the moment, the driving motor 6 drives the threaded rod 8 to rotate, thereby the support plate 3 slides above the support frame 1, the sliding rod 10 slides in the through hole 9, further the resistance wire insert on the heating cylinder 4 is inserted into the pipe fitting, and then the heating cylinder 4 and the heating ring 20 are connected with an external power supply, thereby make cartridge heater 4 and heating collar 20 heat the hot melt adhesive on pipe fitting and resistance wire inserts surface, start rotating motor 12 this moment, make rotating gear 13 rotate, thereby drive cartridge heater 4 and rotate at the internal surface of rotating sleeve 16 through the meshing relation of rotating gear 13 with ring gear 14, through dripping gluey way 5 with the even internal surface of paining at the pipe fitting of hot melt adhesive, wait for the hot melt adhesive cooling shaping after, take out the pipe fitting can.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "left", "right", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation and a specific orientation configuration and operation, and thus, should not be construed as limiting the present invention. Furthermore, "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and the like are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be directly connected or indirectly connected through an intermediate member, or they may be connected through two or more elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

While one embodiment of the present invention has been described in detail, the description is only a preferred embodiment of the present invention and should not be taken as limiting the scope of the invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.