阅读说明：本技术 一种转动惯量连续可变的自适应展开式飞轮 (Self-adaptive expansion type flywheel with continuously variable rotational inertia ) 是由 程哲 李月昊 胡茑庆 陈凌 肖卓 陈家庚 王博政 周洋 于 2020-12-23 设计创作，主要内容包括：本发明公开一种转动惯量连续可变的自适应展开式飞轮,包括飞轮安装盘与若干展开飞轮；所述飞轮安装盘的边缘位置沿飞轮安装盘的周向间隔设有若干与展开飞轮一一对应的飞轮连接部；所述展开飞轮的首端转动连接在对应飞轮连接部上靠近其首端的位置；所述展开飞轮的尾端在展开飞轮的转动过程中具有靠近或远离对应飞轮连接部尾端的行程,进而实现飞轮的转动惯量连续可变。其在不增加额外装置且不利用额外能量的前提下,实现了飞轮转动惯量的连续可变且自适应于不同工况；不仅可根据使用条件设计最大转动惯量与最小转动惯量,具有更广的应用范围,而且结构紧凑,不会过多的增加飞轮的占用空间,同时制造与装配简单,成本低廉,具有良好的工程应用价值。(The invention discloses a self-adaptive expansion type flywheel with continuously variable rotational inertia, which comprises a flywheel mounting disc and a plurality of expansion flywheels; the edge position of the flywheel mounting disc is provided with a plurality of flywheel connecting parts which are in one-to-one correspondence with the unfolded flywheels at intervals along the circumferential direction of the flywheel mounting disc; the head end of the unfolding flywheel is rotatably connected to a position, close to the head end, of the corresponding flywheel connecting part; the tail end of the unfolding flywheel has a stroke close to or far away from the tail end of the corresponding flywheel connecting part in the rotation process of the unfolding flywheel, and therefore the continuous variable of the rotational inertia of the flywheel is achieved. Under the premise of not adding an extra device and not using extra energy, the continuous variable flywheel rotational inertia is realized and the flywheel is adaptive to different working conditions; the flywheel has the advantages that the maximum rotary inertia and the minimum rotary inertia can be designed according to the use conditions, the application range is wider, the structure is compact, the occupied space of the flywheel cannot be excessively increased, the manufacturing and the assembling are simple, the cost is low, and the engineering application value is good.)

1. A self-adaptive expansion type flywheel with continuously variable rotational inertia is characterized by comprising a flywheel mounting disc and a plurality of expansion flywheels;

the edge position of the flywheel mounting disc is provided with a plurality of flywheel connecting parts which are in one-to-one correspondence with the unfolded flywheels at intervals along the circumferential direction of the flywheel mounting disc;

the head end of the unfolding flywheel is rotatably connected to a position, close to the head end, of the corresponding flywheel connecting part;

the tail end of the unfolding flywheel has a stroke close to or far away from the tail end of the corresponding flywheel connecting part in the rotation process of the unfolding flywheel, and therefore the continuous variable of the rotational inertia of the flywheel is achieved.

2. The adaptively expanding flywheel with continuously variable moment of inertia as claimed in claim 1, wherein a torsion spring is disposed on the flywheel connecting portion near the head end thereof, one end of the torsion spring abuts against the head end of the corresponding flywheel connecting portion, and the other end abuts against the head end of the corresponding expanding flywheel, the torsion spring has a pre-tightening force;

when the flywheel mounting disc is in a standing state, under the action of the pre-tightening force of the torsion spring, the tail end of the unfolded flywheel is in a state closest to the tail end of the corresponding flywheel connecting part;

when the rotating speed of the flywheel mounting disc is gradually increased and the rotating centrifugal force is larger than the pre-tightening force of the torsion spring, the tail end of each unfolded flywheel is gradually far away from the tail end of the corresponding flywheel connecting part.

3. The self-adaptive expanding flywheel with continuously variable moment of inertia according to claim 1 or 2, wherein a plurality of spoke-shaped protrusions are arranged at the edge position of the flywheel mounting plate at intervals along the circumferential direction of the flywheel mounting plate, a flywheel connecting part is arranged between every two adjacent spoke-shaped protrusions, and the head end of the flywheel connecting part is a side wall corresponding to the spoke-shaped protrusions.

4. The adaptively expanding flywheel with continuously variable moment of inertia according to claim 1 or 2, wherein the flywheel mounting plate is a flange-shaped disk, each flywheel connecting portion constitutes a large-face end portion of the flange-shaped disk, and the expanding flywheel is of a fan-shaped structure;

when the flywheel mounting discs stand still, the inner circular arcs of the unfolded flywheels are completely attached to the flanges of the flywheel mounting discs;

when the rotating speed of the flywheel mounting disc is gradually increased, the inner circular arc of each unfolded flywheel is gradually far away from the flange of the flywheel mounting disc.

5. The adaptive unfolding flywheel with continuously variable moment of inertia according to claim 1 or 2, wherein the unfolding flywheel is rotationally connected to the corresponding flywheel connecting part through a first pin bolt;

the first pin shaft screw comprises a first nut, a first optical axis section and a first thread section which are sequentially connected from top to bottom, and a first threaded hole is formed in the flywheel connecting part corresponding to the rotating position of the unfolded flywheel;

the first thread section penetrates through the unfolding flywheel and then is in thread fit with the first thread hole, and the unfolding flywheel is rotatably connected to the first optical axis section.

6. The adaptively expanding flywheel having a continuously variable moment of inertia according to claim 2, wherein the torsion spring is provided at the corresponding flywheel coupling part through a second pin bolt;

the second pin shaft screw comprises a second nut, a second optical axis section and a second thread section which are sequentially connected from top to bottom, and a second threaded hole is formed in the flywheel connecting part corresponding to the rotating position of the torsion spring;

the second thread section is in threaded connection with the second thread hole, and the torsion spring is sleeved on the second optical axis section.

7. The self-adaptive expanding flywheel with continuously variable moment of inertia according to claim 1 or 2, further comprising a transmission shaft, wherein the flywheel mounting plate is fixedly sleeved on the transmission shaft.

8. An adaptively expanding flywheel with continuously variable moment of inertia as in claim 1 or 2, wherein the expanding flywheel is made of an iron-based material and the flywheel mounting plate is made of a lightweight metal material.

Technical Field

The invention relates to the technical field of vibration reduction of flywheel type inertial containers, in particular to a self-adaptive expansion type flywheel with continuously variable rotational inertia, and particularly relates to a self-adaptive expansion type flywheel with continuously variable rotational inertia, which can be used for a vibration reduction system comprising an inertial container.

Background

In 2001, Smith, cambridge university, invented "inerter". The new mechanical element can provide a very large amount of inertia with a very small structural mass. An ideal inerter element is defined as a single-channel mechanical element with two relatively independent and free-moving end points that are forced equally and oppositely and are proportional to the relative acceleration. According to the structural principle, the inerter is divided into four types, namely a mechanical type, a hydraulic type, an electromechanical type, an electromagnetic type and the like. In addition, the relative relationship between the transmission motions can be classified into a coaxial linear type, a parallel axis type, a torsion type, and the like. Linear mechanical inerter, most commonly consisting of a transmission mechanism to effect the conversion of motion and a flywheel to store energy and provide the main moment of inertia.

For a disk-shaped flywheel, the moment of inertia of its rotation about its length is quadratic to its radius, i.e.Wherein J is the moment of inertia, m is the flywheel mass, and R is the flywheel radius. When the mass of the flywheel is unchanged, the turning radius of the flywheel is increased, and the rotational inertia of the flywheel is increased. For an inertial container with a fixed rotational inertia flywheel, the inertial mass coefficient of the inertial container cannot adapt to the changing working condition, especially the moment of large load actionThe impact effect caused by the invariable quantity greatly limits the use efficiency of the inerter.

Disclosure of Invention

Aiming at the problems that the flywheel used by a common inertia container in the prior art is invariable in rotational inertia and is difficult to bear instantaneous large load, the invention provides the self-adaptive expansion type flywheel with continuously variable rotational inertia, and the continuous variable and self-adaptive adaptation to different working conditions of the rotational inertia of the flywheel are realized on the premise of not increasing additional devices and not utilizing additional energy.

In order to achieve the aim, the invention provides a self-adaptive expansion type flywheel with continuously variable rotational inertia, which comprises a flywheel mounting disc and a plurality of expansion flywheels;

the edge position of the flywheel mounting disc is provided with a plurality of flywheel connecting parts which are in one-to-one correspondence with the unfolded flywheels at intervals along the circumferential direction of the flywheel mounting disc;

the head end of the unfolding flywheel is rotatably connected to a position, close to the head end, of the corresponding flywheel connecting part;

the tail end of the unfolding flywheel has a stroke close to or far away from the tail end of the corresponding flywheel connecting part in the rotation process of the unfolding flywheel, and therefore the continuous variable of the rotational inertia of the flywheel is achieved.

In one embodiment, a torsion spring is arranged on the flywheel connecting part near the head end of the flywheel connecting part, one end of the torsion spring abuts against the head end of the corresponding flywheel connecting part, the other end of the torsion spring abuts against the head end of the corresponding unfolding flywheel, and the torsion spring has a pre-tightening force;

when the flywheel mounting disc is in a standing state, under the action of the pre-tightening force of the torsion spring, the tail end of the unfolded flywheel is in a state closest to the tail end of the corresponding flywheel connecting part;

when the rotating speed of the flywheel mounting disc is gradually increased and the rotating centrifugal force is larger than the pre-tightening force of the torsion spring, the tail end of each unfolded flywheel is gradually far away from the tail end of the corresponding flywheel connecting part.

In one embodiment, a plurality of spoke-shaped protrusions are arranged at the edge of the flywheel mounting disk at intervals along the circumferential direction of the flywheel mounting disk, a flywheel connecting portion is arranged between every two adjacent spoke-shaped protrusions, and the head end of the flywheel connecting portion is a side wall corresponding to the spoke-shaped protrusions.

In one embodiment, the flywheel mounting plate is a flange-shaped disc, each flywheel connecting part forms a large-face end part of the flange-shaped disc, and the unfolded flywheel is of a fan-shaped structure;

when the flywheel mounting discs stand still, the inner circular arcs of the unfolded flywheels are completely attached to the flanges of the flywheel mounting discs;

when the rotating speed of the flywheel mounting disc is gradually increased, the inner circular arc of each unfolded flywheel is gradually far away from the flange of the flywheel mounting disc.

In one embodiment, the unfolding flywheels are rotatably connected to the corresponding flywheel connecting parts through first pin shaft screws;

the first pin shaft screw comprises a first nut, a first optical axis section and a first thread section which are sequentially connected from top to bottom, and a first threaded hole is formed in the flywheel connecting part corresponding to the rotating position of the unfolded flywheel;

the first thread section penetrates through the unfolding flywheel and then is in thread fit with the first thread hole, and the unfolding flywheel is rotatably connected to the first optical axis section.

In one embodiment, the torsion spring is arranged on the corresponding flywheel connecting part through a second pin shaft screw;

the second pin shaft screw comprises a second nut, a second optical axis section and a second thread section which are sequentially connected from top to bottom, and a second threaded hole is formed in the flywheel connecting part corresponding to the rotating position of the torsion spring;

the second thread section is in threaded connection with the second thread hole, and the torsion spring is sleeved on the second optical axis section.

In one embodiment, the flywheel mounting plate further comprises a transmission shaft, and the flywheel mounting plate is fixedly sleeved on the transmission shaft.

In one embodiment, the deployment flywheel is made of an iron-based material and the flywheel mounting plate is made of a lightweight metal material. .

Compared with the prior art, the self-adaptive expansion type flywheel with continuously variable rotational inertia provided by the invention has the following beneficial effects:

1. under the premise of not increasing additional devices and not utilizing additional energy, the continuous variable flywheel rotational inertia is realized and is adaptive to different working conditions;

2. the structure is compact, and the occupied space of the flywheel is not excessively increased;

3. the maximum rotational inertia and the minimum rotational inertia can be designed according to the use conditions, and the method has a wider application range;

4. the wheel is simple to manufacture and assemble, low in manufacturing cost and good in engineering application value.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is an isometric view of an adaptively expanding flywheel having a continuously variable moment of inertia according to an embodiment of the present invention;

FIG. 2 is a front view of the overall structure of an embodiment of the present invention, wherein the moment of inertia of the self-adaptive expanding flywheel is continuously variable, when each expanding flywheel is expanded;

FIG. 3 is a front view of the overall structure of an embodiment of the present invention, wherein the moment of inertia of the self-adaptive expanding flywheel is continuously variable, when the expanding flywheels are closed;

FIG. 4 is an isometric view of a flywheel mounting plate in an embodiment of the invention;

FIG. 5 is a front view of an embodiment of the present invention with the flywheel deployed;

fig. 6 is a front view of a first pin bolt in an embodiment of the present invention.

Reference numerals: the flywheel comprises a transmission shaft 10, a key 101, a flywheel mounting plate 20, a flywheel connecting portion 201, spoke-shaped protrusions 202, a flange 203, a first threaded hole 204, a second threaded hole 205, a key groove 206, an unfolded flywheel 30, a through hole 301, a torsion spring 40, a first pin shaft screw 50, a first nut 501, a first optical shaft section 502, a first threaded section 503 and a second pin shaft screw 60.

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

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.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes 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 at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "connected," "secured," and the like are to be construed broadly, and for example, "secured" may be a fixed connection, a removable connection, or an integral part; the connection can be mechanical connection, electrical connection, physical connection or wireless communication connection; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In addition, the technical solutions in the embodiments of the present invention may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

Fig. 1-6 show an adaptive unfolding flywheel with continuously variable moment of inertia, which specifically includes a transmission shaft 10, a flywheel mounting plate 20, and a plurality of unfolding flywheels 30. The flywheel mounting plate 20 is mounted on the transmission shaft 10 for spreading the load and position of the flywheel 30. The flywheel mounting disk 20 and the transmission shaft 10 are connected with the key groove 206 through the key 101, however, the connection mode between the flywheel mounting disk 20 and the transmission shaft 10 in this embodiment is not limited to key connection, and only needs to satisfy the connection mode of stably transmitting the torque of the transmission shaft 10 to the flywheel mounting disk 20.

Specifically, the edge position of the flywheel mounting plate 20 is provided with a plurality of flywheel connecting portions 201 corresponding to the unfolded flywheels 30 one by one at intervals along the circumferential direction of the flywheel mounting plate 20. The head end of the unfolding flywheel 30 is rotatably connected to a position close to the head end of the corresponding flywheel connecting portion 201 on the unfolding flywheel connecting portion, the tail end of the unfolding flywheel 30 has a stroke close to or far away from the tail end of the corresponding flywheel connecting portion 201 in the rotating process of the unfolding flywheel 30, wherein no connecting structure exists between the tail end of the unfolding flywheel 30 and the flywheel mounting disc 20, the tail end of the unfolding flywheel 30 can be gradually far away from the tail end of the corresponding flywheel connecting portion 201 under the action of centrifugal force in the rotating process of the flywheel mounting disc 20, the turning radius of the flywheel is continuously increased in the process, the rotary inertia of the flywheel is increased, the increasing process is continuous and is adaptive to the rotating speed of the flywheel mounting disc 20, and the rotary inertia of the flywheel is continuously variable in a self-adaptive.

More specifically, the flywheel connecting portion 201 is provided with a torsion spring 40 at a position near the leading end thereof, and one end of the torsion spring 40 abuts against the leading end of the corresponding flywheel connecting portion 201 and the other end abuts against the leading end of the corresponding deployment flywheel 30. The torsion spring 40 has a pre-tightening force, which urges the tail end of the unwinding flywheel 30 to approach the tail end of the corresponding flywheel connecting portion 201. Therefore, when the flywheel mounting plate 20 is in the static state, the unfolding flywheel 30 is only subjected to the pre-tightening force of the torsion spring 40, and under the pre-tightening force, the tail end of the unfolding flywheel 30 is in a state closest to the tail end of the corresponding flywheel connecting portion 201, and the turning radius of the flywheel is at the minimum. When the rotation speed of the flywheel mounting disc 20 is gradually increased, the rotating centrifugal force borne by the unfolding flywheels 30 is gradually increased, and when the rotating centrifugal force is greater than the pre-tightening force of the torsion spring 40, the tail end of each unfolding flywheel 30 is gradually far away from the tail end of the corresponding flywheel connecting part 201 under the action of the rotating centrifugal force, so that the rotation radius of the flywheels is gradually increased, and the continuous change of the rotational inertia of the flywheels is realized.

Preferably, in addition to the abutting connection between the two ends of the torsion spring 40 and the flywheel connecting portion 201 and the unfolding flywheel 30, a snap connection or a hook connection may be adopted to prevent the torsion spring 40 from deflecting during the stress.

In a preferred embodiment, a plurality of spoke-shaped protrusions 202 are arranged at intervals along the circumferential direction of the flywheel mounting disk 20 at the edge position of the flywheel mounting disk 20, a flywheel connecting portion 201 is arranged between every two adjacent spoke-shaped protrusions 202, and the head end of the flywheel connecting portion 201 is a side wall corresponding to the spoke-shaped protrusions 202. The spoke-shaped protrusions 202 not only have the function of connecting the torsion springs 40, but also have the function of limiting the unfolded flywheels 30, and avoid collision between adjacent unfolded flywheels 30 due to overlarge rotation angles.

In the present embodiment, the flywheel mounting plate 20 is a flange-shaped disk, which specifically includes an inner flange 203 and a large-face end portion that surrounds the flange 203, wherein each flywheel attachment portion 201 constitutes the large-face end portion of the flange-shaped disk. The expanding flywheel 30 has a fan-shaped structure, the radius of the inner arc is equal to that of the flange 203, and the size of the outer arc can be changed according to the required moment of inertia. When the flywheel mounting disc 20 is in a standing state, the inner circular arcs of the unfolded flywheels 30 are completely attached to the flange 203 of the flywheel mounting disc 20; when the rotational speed of the flywheel mounting plate 20 is gradually increased to a certain level, the inner circular arc of each deployed flywheel 30 is gradually separated from the flange 203 of the flywheel mounting plate 20.

In this embodiment, the unfolding flywheels 30 are rotatably connected to the corresponding flywheel connecting portions 201 by the first pin screws 50. The first pin shaft screw 50 comprises a first nut 501, a first optical axis section 502 and a first thread section 503 which are sequentially connected from top to bottom, a first threaded hole 204 is formed in the flywheel connecting portion 201 corresponding to the rotating position of the unfolding flywheel 30, and a through hole 301 corresponding to the first threaded hole 204 is formed in the unfolding flywheel 30; the first threaded section 503 is in threaded fit with the first threaded hole 204 after passing through the through hole 301 on the unfolding flywheel 30, and the unfolding flywheel 30 is rotatably connected to the first optical axis section 502. The first nut 501 is used to limit the play of the unwinding flywheel 30 along the length of the first pin bolt 50. Preferably, the first nut 501 has a straight groove for assembling and disassembling the universal tool, but not limited to the straight groove, and the first nut can be matched with the universal assembling and disassembling tool. Of course, the connection structure between the unfolding flywheel 30 and the corresponding flywheel connecting portion 201 is not limited to the first pin bolt 50, and other connecting members, such as hinges, may be used to achieve the same effect.

In this embodiment, the torsion spring 40 is disposed on the corresponding flywheel connecting portion 201 through the second pin bolt 60. The second pin shaft screw 60 comprises a second nut, a second optical axis section and a second thread section which are sequentially connected from top to bottom, and a second threaded hole 205 is formed in the flywheel connecting portion 201 corresponding to the rotating position of the torsion spring 40; the second threaded section is threaded in the second threaded hole 205, and the torsion spring 40 is sleeved on the second optical axis section. The second nut is used for limiting the torsion spring 40 from moving along the length direction of the second pin shaft screw, wherein preferably, an embedded groove capable of being embedded into the torsion spring 40 is formed on the second optical axis section, so as to further limit the movement of the torsion spring 40. Further preferably, the second nut is provided with a straight groove for dismounting and mounting the general tool, but not limited to the straight groove, and the straight groove can be matched with the general dismounting and mounting tool. Of course, the connection structure between the torsion spring 40 and the corresponding flywheel connection portion 201 is not limited to the second pin bolt, and other connection members, such as a fixed shaft, may be used to achieve the same effect.

In this embodiment, the flywheel 30 is required to provide a large portion of the moment of inertia and to serve as a variable moment of inertia, while the flywheel mounting plate 20 is required to provide a small portion of the moment of inertia, thereby increasing the amount of variation in the total moment of inertia. For this purpose, the deployment flywheel 30 is made of an iron-based material including a carbon steel material, a stainless steel material, and the like, and the flywheel mounting plate 20 is made of a lightweight metal material including 6061 alloy, duralumin, and the like.

The embodiment also discloses an assembly method of the self-adaptive expansion type flywheel with continuously variable rotational inertia, which specifically comprises the following steps:

a method for assembling an adaptive unfolding flywheel with continuously variable rotational inertia comprises the following steps:

step 1, installing a torsion spring 40: the torsion spring 40 is sleeved on the second pin shaft screw 60, and the second pin shaft screw and the torsion spring 40 are installed on the flywheel mounting plate 20 through threaded connection by means of a disassembling tool.

Step 2, installing and unfolding the flywheel 30: the first pin bolt 50 is inserted into the through hole 301 of the unfolding flywheel 304, and the first pin bolt 50 and the unfolding flywheel 30 are installed on the flywheel mounting plate 20 through threaded connection by means of a disassembling tool.

And 3, repeating the steps 1 and 2, and mounting a plurality of groups of torsion springs 40 and the unfolded flywheel 30 on the flywheel mounting plate 20.

And step 4, completing the connection between the flywheel and the transmission shaft 10: the flywheel mounting plate 20 is mounted on the transmission shaft 10 by a connection means such as a flat key connection.

The present embodiment also provides a specific example of the above adaptive unfolding flywheel with continuously variable rotational inertia, and its main parameters include: the radius of the inner circular arc of the unfolding flywheel 30 is 50mm, and the radius of the outer circular arc thereof is 80 mm. The material of the unfolding flywheel 30 is 304 stainless steel, and the material of the flywheel mounting plate 20 is 6061 alloy. Neglecting the moment of inertia of the transmission shaft 10 and the torsion spring 40, when a plurality of unfolding flywheels 30 are closed, the moment of inertia is continuously variable and adaptiveThe integral rotary inertia of the unfolded flywheel around the rotating shaft is 7.39 multiplied by 106 g.mm²When the plurality of unfolding flywheels 30 are unfolded to the limit position, the whole self-adaptive unfolding flywheels with continuously variable moment of inertia is 1.13 multiplied by 107 g.mm around the rotating shaft². It can be seen that the degree of expansion of the expanding flywheel 30 greatly affects the overall moment of inertia, and the degree of expansion varies with the rotation speed of the transmission shaft 10, thereby achieving the practical function of the self-adaptive expanding flywheel in which the moment of inertia is continuously variable. And the radii of the inner and outer circular arcs of the unfolding flywheel 30 can be designed according to the design requirements, so that different integral rotational inertia can be obtained.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.