阅读说明：本技术 一种安全性高的地面光伏用铜铝连接器 (High-safety copper-aluminum connector for ground photovoltaic ) 是由 陈友林 李小华 孙标山 肖飞 杨凯彪 于 2021-06-28 设计创作，主要内容包括：本发明公开了一种安全性高的地面光伏用铜铝连接器,涉及光伏连接技术领域。该高的地面光伏用铜铝连接器,包括安装支架,所述安装支架中间位置安装有连接件,所述连接件左右两侧安装有第一阻水件,所述第一阻水件和所述连接件之间安装有第二阻水件,所述第二阻水件和所述连接件之间设有储气仓,所述第二阻水件和所述储气仓上的滑盖通过连杆铰链连接,所述储气仓内部设有警报件,所述第一阻水件和所述第二阻水件之间设有安装在所述安装支架侧壁的紧固件,所述第一阻水件外侧壁被外壳包裹。该安全性高的地面光伏用铜铝连接器,提高了铜铝连接器的阻水性能,增加了铜铝连接器进水预警功能,保证了导线连接的稳定性。(The invention discloses a high-safety copper-aluminum connector for ground photovoltaic, and relates to the technical field of photovoltaic connection. This high copper aluminium connector for ground photovoltaic, including the installing support, the connecting piece is installed to the installing support intermediate position, first piece that blocks water is installed to the connecting piece left and right sides, first piece that blocks water with install the second piece that blocks water between the connecting piece, the second block water with be equipped with the gas storage storehouse between the connecting piece, the second block water with sliding closure on the gas storage storehouse passes through connecting rod hinged joint, the inside alarm piece that is equipped with in gas storage storehouse, first piece that blocks water with be equipped with between the second piece that blocks water and install the fastener of installing support lateral wall, first piece lateral wall that blocks water is wrapped up by the shell. This high ground copper aluminium connector for photovoltaic of security has improved the water blocking performance of copper aluminium connector, has increased copper aluminium connector early warning function of intaking, has guaranteed the stability that the wire is connected.)

1. The high-safety copper-aluminum connector for ground photovoltaic comprises a mounting bracket (5), a connecting piece (28) is mounted in the middle of the mounting bracket (5), first water blocking pieces (3) are mounted on the left side and the right side of the connecting piece (28), a second water blocking piece (9) is mounted between the first water blocking piece (3) and the connecting piece (28), a gas storage bin (7) is arranged between the second water blocking piece (9) and the connecting piece (28), an alarm piece (8) is arranged inside the gas storage bin (7), a fastening piece (4) mounted on the side wall of the mounting bracket (5) is arranged between the first water blocking piece (3) and the second water blocking piece (9), and the outer side wall of the first water blocking piece (3) is wrapped by a shell (2);

a first mounting groove (15) is formed in the middle of the mounting bracket (5), second mounting grooves (14) are formed in two sides of the first mounting groove (15), a first mounting hole (13) is formed between two ends of the mounting bracket (5) and the second mounting grooves (14), and the first mounting hole (13) penetrates through the side wall of the mounting bracket (5);

a boss (22) is arranged in the middle of the connecting piece (28), circular truncated cone-shaped grooves (23) are formed in the two ends of the connecting piece, the boss (22) is installed in the first installation groove (15), and the top end of the lead 1 is installed at the bottoms of the circular truncated cone-shaped grooves (23);

the first water-blocking piece (3) wraps the mounting bracket (5), the inner wall of the first water-blocking piece (3) is tightly attached to the outer wall of the mounting bracket (5), and the outer wall of the first water-blocking piece (3) is tightly attached to the inner wall of the shell (2);

the second water-blocking piece (9) is made of water-swelling rubber, is arranged in the second mounting groove (14) and is positioned between the connecting piece (28) and the first water-blocking piece (3), and the inner wall of the second water-blocking piece (9) is tightly attached to the outer wall of the lead (1);

the fastening piece (4) is arranged in the first mounting hole (13), the lower end of the fastening piece (4) is tightly propped against the outer wall of the lead (1), and the upper end of the fastening piece (4) is tightly clung to the inner wall of the first water-blocking piece (3);

the gas storage bin (7) is arranged on the inner side wall of the mounting bracket (5) between the connecting piece (28) and the second water-blocking piece (9);

the alarm member (8) is positioned inside the gas storage bin (7);

the inner side wall of the shell (2) is tightly attached to the outer side wall of the first water-blocking piece (3).

2. The high-safety copper-aluminum connector for ground photovoltaic use according to claim 1, wherein sheet-shaped water blocking plates (6) are mounted at two ends of the mounting bracket (5), the sheet-shaped water blocking plates (6) are sequentially stacked and surround one circle to form a circular truncated cone shape, and inner side walls at two ends of the first water blocking piece (3) are tightly attached to outer side walls of the sheet-shaped water blocking plates (6).

3. The high ground copper aluminium connector for photovoltaic of security according to claim 1, fastener (4) first half is pull rod (16), lower half is eccentric gear (17), fastener (4) are installed in first mounting hole (13), gear arrangement groove (24) and second mounting hole (26) are seted up for solid pole, the latter half in pull rod (16) upper portion, eccentric gear (17) both sides face is equipped with pivot (25), pivot (25) are fixed in the non-centre of a circle position of gear, pivot (25) are installed in second mounting hole (26), eccentric gear (17) are hugged closely apart from the nearest tooth of pivot (25) wire (1) lateral wall.

4. The high ground copper aluminium connector for photovoltaic of security according to claim 1, gas storage bin (7) installation is located on installing support (5) inside wall between connecting piece (28) and second piece (9) that blocks water, store compressed inert gas in the gas storage bin (7), gas storage bin (7) inside wall with installing support (5) inside wall links to each other through gas pocket (27), gas pocket (27) are in the gas outlet surface of installing support (5) inside wall is equipped with slide rail (18), be equipped with sliding closure (19) in slide rail (18), sliding closure (19) cover the gas outlet, sliding closure (19) with second piece (9) side-mounting rotates swivel mount (20) of connecting, two swivel mounts (20) are through connecting rod (21) hinged joint.

5. The high-safety ground photovoltaic copper-aluminum connector as claimed in claim 4, wherein the sliding rail (18) is circular, the air outlet is formed in the bottom of the sliding rail (18), the sliding cover (19) is semi-annular, and one end of the sliding cover (19) is hinged to the side face of the second water blocking piece (9) through a connecting rod (21).

6. The high-safety copper-aluminum connector for ground photovoltaic use as claimed in claim 4, wherein a baffle (11) is arranged in the gas storage bin (7), a spring (10) is arranged on the back of the baffle (11) for supporting, the pressure of the spring (10) on the baffle (11) is higher than a standard atmospheric pressure, and an electrical contact (12) is arranged on the front of the baffle (11).

Technical Field

The invention relates to the technical field of photovoltaic connection, in particular to a ground photovoltaic copper-aluminum connector with high safety.

Background

In the photovoltaic cable, in order to facilitate wiring, the cable is inevitably required to be connected, and because the existing photovoltaic circuit is mostly changed into an aluminum or aluminum alloy conductor cable, copper and aluminum connection is involved during wiring, the copper and aluminum connection needs to be isolated from external water, so as to avoid the electrochemical corrosion problem between copper and aluminum, therefore, the sealing performance of the connector can be very important, the traditional copper-aluminum connector is only sealed by a sealing ring with a certain diameter in the using process, the traditional sealing ring is only sealed by the self tension, after long-time plastic shaping, the tension is reduced, further a gap is generated, the sealing effect is not durable, the two contacts of the traditional copper-aluminum connector are in rigid contact, and the traditional copper-aluminum connector is easy to separate when being subjected to vibration and impact, and in the wiring process, the requirement on the distance precision between the cables at two ends is higher, the wiring is time-consuming and labor-consuming.

Disclosure of Invention

The invention provides a copper-aluminum connector with high safety, aiming at the problems of poor waterproof effect and easy loosening of a wire of the existing copper-aluminum connector, solving the problem that the existing copper-aluminum connector is easy to damage by water inflow, and achieving the purpose of improving the safety of the copper-aluminum connector.

A high-safety copper-aluminum connector for ground photovoltaic comprises a mounting bracket, wherein a connecting piece is mounted in the middle of the mounting bracket, first water blocking pieces are mounted on the left side and the right side of the connecting piece, a second water blocking piece is mounted between the first water blocking piece and the connecting piece, an air storage bin is arranged between the second water blocking piece and the connecting piece, an alarm piece is arranged inside the air storage bin, a fastener mounted on the side wall of the mounting bracket is arranged between the first water blocking piece and the second water blocking piece, and the outer side wall of the first water blocking piece is wrapped by a shell;

a first mounting groove is formed in the middle of the mounting bracket, second mounting grooves are formed in two sides of the first mounting groove, a first mounting hole is formed between two ends of the mounting bracket and the second mounting grooves, and the first mounting hole penetrates through the side wall of the mounting bracket;

a boss is arranged in the middle of the connecting piece, and truncated cone-shaped grooves are arranged at two ends of the connecting piece;

the first water-blocking piece wraps the mounting bracket, the inner wall of the first water-blocking piece is tightly attached to the outer wall of the mounting bracket, and the outer wall of the first water-blocking piece is tightly attached to the inner wall of the shell;

the second water-blocking piece is made of water-swelling rubber, is arranged in the second mounting groove and is positioned between the connecting piece and the first water-blocking piece, and the inner wall of the second water-blocking piece is tightly attached to the outer wall of the lead;

the fastener is arranged in the first mounting hole, the lower end of the fastener is tightly propped against the outer wall of the lead, and the upper end of the fastener is tightly clung to the inner wall of the first water-blocking piece;

the gas storage bin is arranged on the inner side wall of the mounting bracket between the connecting piece and the second water-blocking piece;

the alarm piece is positioned inside the gas storage bin;

the inner side wall of the shell is tightly attached to the outer side wall of the first water blocking piece.

Further, the flaky water blocking plates are installed at the two ends of the installing support, the flaky water blocking plates are sequentially stacked and surround a circle to form a circular truncated cone, and the inner side walls of the two ends of the first water blocking piece are tightly attached to the outer side walls of the flaky water blocking plates.

Further, the upper half part of the fastener is a pull rod, the lower half part of the fastener is an eccentric gear, the fastener is installed in the first installation hole, the upper portion of the pull rod is a solid rod, a gear installation groove and a second installation hole are formed in the lower half part of the pull rod, rotating shafts are arranged on two side faces of the eccentric gear, the rotating shafts are fixed at the non-circle center positions of the gears, the rotating shafts are installed in the second installation hole, and teeth, which are closest to the rotating shafts, of the eccentric gear are tightly attached to the side wall of the wire.

Further, the gas storage bin installation is located the connecting piece with on the installing support inside wall between the second piece that blocks water, store compressed inert gas in the gas storage bin, the gas storage bin inside wall with the installing support inside wall passes through the gas pocket and links to each other, the gas pocket is in the gas outlet surface of installing support inside wall is equipped with the slide rail, be equipped with the sliding closure in the slide rail, the sliding closure covers the gas outlet, the sliding closure with the second piece that blocks water side-mounting rotates the swivel mount of connection, and two swivel mounts pass through connecting rod hinged joint.

Furthermore, the slide rail is circular, the air outlet is arranged at the bottom of the slide rail, the sliding cover is semi-annular, and one end of the sliding cover is connected with the side face of the second water-blocking piece through a connecting rod hinge.

Furthermore, a baffle is arranged in the gas storage bin, a spring support is arranged on the back of the baffle, the pressure of the spring on the baffle is higher than a standard atmospheric pressure, and an electric contact is arranged on the front of the baffle.

The invention provides a high-safety copper-aluminum connector for ground photovoltaic, which has the following effects:

1. this high ground copper aluminium connector for photovoltaic of security, first piece that blocks water is made by the swelling rubber that absorbs water and tentatively blocks external a large amount of water, and first group water piece absorbs water the swelling extrusion the slice board that blocks water, the slice board that blocks water with the wire outer wall is closely laminated and is further blocked water.

2. This copper aluminium connector for ground photovoltaic of security height, second water component is made by the expansion rubber that absorbs water and blocks the moisture is not blocked to first water blocking piece, the expansion that absorbs water of second water component removes the sliding closure through the connecting rod and then makes compressed inert gas blowout, makes second water blocking piece, the wire with pressure in the cavity between the connecting piece is greater than external atmospheric pressure, further blocks that water gets into the link and inert gas can also prevent the production of electric arc.

3. This high ground copper aluminium connector for photovoltaic of security, the baffle back is equipped with the spring and openly set up the contact constitutes jointly the alarm piece, the spring is right the atmospheric pressure of baffle is greater than standard atmospheric pressure, the alarm piece is installed in the gas storage storehouse, when the inside gas pressure of gas storage storehouse equals a standard atmospheric pressure and can't block water, the spring extrusion the baffle makes the contact closure send out the police dispatch newspaper, makes the early warning before copper aluminium connector is intake and is damaged, notifies the maintenance personal and changes.

4. This high ground copper aluminium connector for photovoltaic of security, the slide rail does the slide rail is ring shape, the sliding closure is the semi-annular, can prevent that external rocking from opening the gas outlet.

5. This high ground copper aluminium connector for photovoltaic of security, the pull rod with eccentric gear constitutes jointly the fastener presses the pull rod makes eccentric gear tightly supports at the wire lateral wall fixedly apart from the nearest tooth of pivot, first piece that hinders water absorbs water the inflation extrusion the pull rod further makes fastener locking wire.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a copper-aluminum connector according to an embodiment of the present invention;

fig. 2 is a schematic cross-sectional view of a copper-aluminum connector according to an embodiment of the present invention;

FIG. 3 is an enlarged schematic view of a point A provided in the embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a mounting bracket according to an embodiment of the present invention;

FIG. 5 is a cross-sectional view of a mounting bracket according to an embodiment of the present invention;

FIG. 6 is a schematic structural view of a fastener provided in accordance with an embodiment of the present invention;

FIG. 7 is a schematic structural view of a gas storage bin according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a connector according to an embodiment of the present invention.

Description of the main element symbols:

1-a wire; 2-a housing; 3-a first water-blocking member; 4-a fastener; 5, mounting a bracket; 6-sheet water-blocking board; 7-gas storage; 8-an alarm; 9-a second water-blocking member; 10-a spring; 11-a baffle plate; 12-a contact; 13-a first mounting hole; 14-a second mounting groove; 15-a first mounting groove; 16-a pull rod; 17-an eccentric gear; 18-a slide rail; 19-a slide cover; 20-transposition; 21-a connecting rod; 22-a boss; 23-a groove; 24-a gear seating groove; 25-a rotating shaft; 26-a second mounting hole; 27-air holes; 28-connecting piece.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Referring to fig. 1-5, a high-safety copper-aluminum connector for ground photovoltaic comprises a mounting bracket 5, a connecting piece 28 is mounted in the middle of the mounting bracket 5, first water blocking pieces 3 are mounted on the left side and the right side of the connecting piece 28, a second water blocking piece 9 is mounted between the first water blocking piece 3 and the connecting piece 28, an air storage bin 7 is arranged between the second water blocking piece 9 and the connecting piece 28, an alarm piece 8 is arranged inside the air storage bin 7, a fastener 4 mounted on the side wall of the mounting bracket 5 is arranged between the first water blocking piece 3 and the second water blocking piece 9, the outer side wall of the first water blocking piece 3 is wrapped by a shell 2, the shell 2 primarily blocks outside water, and the shell 2 is made of a hard material and is corrosion-resistant and impact-resistant;

referring to fig. 4 and 5, a first mounting groove 15 is formed in the middle of the mounting bracket 5, second mounting grooves 14 are formed in two sides of the first mounting groove 15, a first mounting hole 13 is formed between two ends of the mounting bracket 5 and the second mounting grooves 14, the first mounting hole 13 penetrates through the side wall of the mounting bracket 5, and the connecting member 28, the first water blocking member 3, the second water blocking member 9, the fastening member 4 and the gas storage bin 7 are all mounted on the mounting bracket 5;

please refer to fig. 2 and 8, a boss 22 is arranged in the middle of the connecting member 28, truncated cone-shaped grooves 23 are arranged at two ends of the connecting member 28, the boss 22 is installed in the first installation groove 15, the top end of the wire 1 is installed at the bottom of the truncated cone-shaped groove 23, the connecting member 28 is used for conducting the wires 1 at two sides, and the connecting member 28 is made of a non-metal conductive material with conductivity higher than that of copper and aluminum;

referring to fig. 2, the first water blocking member 3 wraps the mounting bracket 5, the inner wall of the first water blocking member 3 is tightly attached to the outer wall of the mounting bracket 5, the outer wall of the first water blocking member 3 is tightly attached to the inner wall of the housing 2, and the first water blocking member 3 absorbs water which is not blocked by the housing 2 and then expands to be in closer contact with the wire 1, so that the water blocking performance is enhanced;

further, please refer to fig. 2, fig. 4 and fig. 5, the two ends of the mounting bracket 5 are provided with the sheet-shaped water-blocking plates 6, the sheet-shaped water-blocking plates 6 are sequentially stacked and surround a circle to form a circular truncated cone shape, the inner side walls of the two ends of the first water-blocking piece 3 are tightly attached to the outer side walls of the sheet-shaped water-blocking plates 6, the first water-blocking piece 3 absorbs water and expands to extrude the sheet-shaped water-blocking plates 6, so that the bottom of the sheet-shaped water-blocking plates 6 is tightly attached to the side walls of the lead 1, water seeped from the inner side walls of the first water-blocking piece 3 is blocked, and the waterproof performance of the copper-aluminum connector is further improved.

Referring to fig. 2 and 5, the second water-blocking member 9 is made of water-swelling rubber, is installed in the second installation groove 14 and is located between the connecting member 28 and the first water-blocking member 3, the inner wall of the second water-blocking member 9 is tightly attached to the outer wall of the lead 1, and the second water-blocking member 9 absorbs water which cannot be blocked by the first water-blocking member 3 and the sheet-shaped water-blocking plate 6;

further, referring to fig. 2, 5 and 7, the gas storage bin 7 is installed on the inner side wall of the installation support 5 between the connecting member 28 and the second water blocking member 9, compressed inert gas is stored in the gas storage bin 7, the inner side wall of the gas storage bin 7 is connected with the inner side wall of the installation support 5 through a gas hole 27, the gas hole 27 is provided with a slide rail 18 on the surface of the gas outlet of the inner side wall of the installation support 5, a slide cover 19 is arranged in the slide rail 18, the slide cover 19 covers the gas outlet, the slide cover 19 is hinged with the side surface of the second water blocking member 9 through a connecting rod 21, the second water blocking member is made of water-absorbing expansion rubber to block the first water blocking member 3 from not blocking water, the second water blocking member absorbs water to expand and moves the slide cover 19 through the connecting rod 21 to spray the compressed inert gas, so that the second water blocking member 9, the pressure in the cavity between the conductor 1 and the connector 28 is greater than the outside atmospheric pressure, further blocking water from entering the connector and the inert gas also preventing the generation of an arc;

further, referring to fig. 7, the slide rail 18 is circular, the gas outlet is at the bottom of the slide rail 18, the sliding cover 19 is semi-circular, the sliding cover 19 and the second water blocking member 9 are provided with rotary seats 20 rotatably connected at their side surfaces, and the two rotary seats 20 are hinged by a connecting rod 21 to prevent external shaking from opening the gas outlet to leak inert gas;

further, please refer to fig. 2 and 3, a baffle 11 is arranged in the gas storage bin 7, a spring 10 is arranged on the back of the baffle 11 for supporting, the pressure of the spring 10 on the baffle 11 is greater than a standard atmospheric pressure, an electrical contact 12 is arranged on the front of the baffle 11, when the gas pressure inside the gas storage bin 7 is equal to the standard atmospheric pressure and water cannot be blocked, the spring 10 presses the baffle 11 to close the contact 12 to give an alarm, and an early warning is given before the copper-aluminum connector is damaged due to water inflow, so as to inform maintenance personnel to replace the copper-aluminum connector.

Referring to fig. 2, 4, 5 and 6, the fastening member 4 is installed in the first installation hole 13, the lower end of the fastening member 4 tightly abuts against the outer wall of the lead 1, the upper end of the fastening member 4 tightly abuts against the inner wall of the first water blocking member 3, and the fastening member 4 is used for fixing the lead 1;

further, please refer to fig. 6, the upper half of the fastening member 4 is a pull rod 16, the lower half is an eccentric gear 17, the fastening member 4 is installed in the first installation hole 13, the upper part of the pull rod 16 is a solid rod, the lower half is provided with a gear installation groove 24 and a second installation hole 26, two side surfaces of the eccentric gear 17 are provided with a rotating shaft 25, the rotating shaft 25 is fixed at a non-circle center position of the gear, the rotating shaft 25 is installed in the second installation hole 26, a tooth of the eccentric gear 17 closest to the rotating shaft 25 is tightly attached to a side wall of the lead 1, when the lead 1 is subjected to an outward force, the eccentric gear 17 can clamp the lead 1, and prevent the lead 1 from moving.

The specific working principle is as follows: the utility model provides a high ground copper aluminium connector for photovoltaic of security, it can be absorbed by first water-blocking piece 3 to block getting into copper aluminium connector inside when the water-washed crosses hard shell 2, the expansion that absorbs water of first water-blocking piece 3 can extrude wire 1 and slice water-blocking plate 6, the 3 inner walls of first water-blocking piece can block the inflow of water with 1 outer wall connection of wire closely more, it is inseparabler that the 3 expansion extrusion slice water-blocking plate of first water-blocking piece 6 makes slice water-blocking plate 6 and the laminating of 1 outer wall of wire, further block inside rivers get into copper aluminium connector, the water absorption that the slice water-blocking plate 6 blocked will be broken through to second water-blocking piece 9. If the water quantity is too large, the second water blocking piece 9 can expand to generate large deformation so as to extrude the connecting rod 21 to push the sliding cover 19 open, the compressed inert gas flows out of the air hole 27 to fill a cavity between the connecting piece 28 and the second water blocking piece 9, the pressure in the cavity is greater than the external pressure, the compressed inert gas can extrude the water on the second water blocking piece 9 outwards, when the water on the second water blocking piece 9 is reduced to a certain degree, the second water blocking piece 9 can contract so as to pull the sliding cover 19 to block the air hole 27 through the connecting rod 21. If the absorptive moisture of second piece 9 that blocks water is too much, compressed inert gas releases continuously, when gas pressure equals external gas pressure in gas storage bin 7, spring 10 can promote baffle 11 and then make baffle 11 front contact 12 laminate with alarm 8's contact 12, alarm 8 sends the alarm of leaking, advance warning before the damage of intaking of copper aluminium connector, inform maintenance personal to come the maintenance, inert gas can cool down and prevent the production of electric arc from increasing the life of wire 1.

When the external lead 1 shakes the copper-aluminum connector, the lead 1 can be subjected to an outward force, the teeth of the eccentric gear 17 closest to the rotating shaft 25 cling to the side wall of the lead 1 to clamp the lead 1, the lead 1 is prevented from moving outwards, and the lead 1 is fixed.

In all examples shown and described herein, any particular value should be construed as merely exemplary, and not as a limitation, and thus other examples of example embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

The above examples are merely illustrative of several embodiments of the present invention, and the description thereof is more specific and detailed, but not to be construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.