阅读说明：本技术 一种无框光伏瓦的夹持系统 (Clamping system of frameless photovoltaic tile ) 是由 张艺凡 于 2020-05-22 设计创作，主要内容包括：本发明涉及一种无框光伏瓦的夹持系统。所述无框光伏瓦的夹持系统包括夹持组件与无框光伏瓦,夹持组件包括夹持框、两个夹持架与两个翻转架,夹持框内形成有夹持狭槽,两个夹持架分别转动地安装于夹持框的相对两侧,夹持框的相对两端均开设有贯通槽,两个翻转架分别转动地安装于夹持框的相对两端,无框光伏瓦插设于夹持狭槽内。所述无框光伏瓦的夹持系统能够保护无框光伏瓦,以避免无框光伏瓦发生隐裂。(The invention relates to a clamping system for frameless photovoltaic tiles. The clamping system of the frameless photovoltaic tile comprises a clamping assembly and the frameless photovoltaic tile, the clamping assembly comprises a clamping frame, two clamping frames and two turnover frames, a clamping slot is formed in the clamping frame, the two clamping frames are respectively and rotatably installed on the two opposite sides of the clamping frame, through grooves are formed in the two opposite ends of the clamping frame, the two turnover frames are respectively and rotatably installed on the two opposite ends of the clamping frame, and the frameless photovoltaic tile is inserted into the clamping slot. The clamping system of the frameless photovoltaic tile can protect the frameless photovoltaic tile so as to avoid hidden cracking of the frameless photovoltaic tile.)

1. The clamping system of the frameless photovoltaic tile is characterized by comprising a clamping assembly and the frameless photovoltaic tile, wherein the clamping assembly comprises a clamping frame, two clamping frames and two turnover frames, a clamping slot is formed in the clamping frame, the two clamping frames are respectively and rotatably installed on the two opposite sides of the clamping frame, through grooves are formed in the two opposite ends of the clamping frame, the two turnover frames are respectively and rotatably installed on the two opposite ends of the clamping frame, the frameless photovoltaic tile is inserted into the clamping slot, the two clamping frames are respectively clamped on the two opposite sides of the frameless photovoltaic tile, and the two turnover frames are respectively used for being turned and clamped into the two through grooves so as to directly abut against and protect the corner of the frameless photovoltaic tile.

2. The frameless photovoltaic tile clamping system of claim 1, wherein the clamping frame comprises two clamping walls, the two clamping walls being disposed opposite one another, the clamping slot being located between the two clamping walls, the two clamping brackets being mounted on the two clamping walls, respectively.

3. The frameless photovoltaic tile clamping system of claim 2, wherein the clamping frame comprises two deflection plates, a rotation shaft and a clamping structure, wherein the two deflection plates are rotatably connected to the top of the clamping wall and are spaced apart from each other, an exposed space is formed between the two deflection plates, opposite ends of the rotation shaft are respectively connected to the tops of the two deflection plates, and the clamping structure is mounted on the rotation shaft.

4. The frameless photovoltaic tile clamping system of claim 3, wherein the clamping structure comprises a connecting strip connected to the rotatable shaft, two connecting strips vertically protruding from opposite ends of the connecting strip, a mandrel connected to opposite ends of the connecting strip, and a plurality of elastic wraps sequentially fitted around the rotatable shaft.

5. The frameless photovoltaic tile clamping system of claim 4, wherein the distance between the clamping structures of two clamping frames gradually decreases in a vertically upward direction, with a gap formed between each two adjacent elastic wraps.

6. The frameless photovoltaic tile clamping system of claim 5, wherein the through slots are located at the bottom of the end walls of the clamping frame, the through slots are in communication with the clamping slots, each roll-over stand comprises a pivot end and a retaining end which are oppositely arranged, the pivot end is rotatably connected to the top of the end walls of the clamping frame, and the retaining end is convexly provided with a flexible retaining block which is used for being clamped into the through slots.

7. The frameless photovoltaic tile clamping system according to claim 6, further comprising a moving assembly, wherein the moving assembly comprises a supporting plate, a metal plate moving frame and two supporting studs, a narrow groove is formed in the center of the bottom of the clamping frame, an inlet groove is formed in the middle of the narrow groove, the inlet groove penetrates through the bottom surface of the clamping frame, the supporting plate supports against the bottom surface of the clamping frame, and the metal plate moving frame is fixed on the supporting plate through the two supporting studs.

8. The clamping system of frameless photovoltaic tile as recited in claim 7, wherein the middle portion of the supporting plate is provided with a through body, the through body is arranged in the entrance slot in a protruding manner, the top end of the through body is provided with an insertion plate in a protruding manner, and the insertion plate is inserted in the elongated slot.

9. The clamping system of claim 8, wherein the holding plate has two threaded holes, the metal plate moving frame has two through holes, the two holding studs are respectively inserted into the two through holes and respectively screwed into the two threaded holes, and the ends of the holding studs are held on the bottom surface of the clamping frame.

10. The clamping system of the frameless photovoltaic tile as recited in claim 9, wherein the two holding studs are located on two opposite sides of the two entry slots, respectively, and two entry holes are further formed in a side of the sheet metal moving frame away from the holding plate, the two entry holes being aligned with the two through holes, respectively, for a driver to enter to drive the holding studs to rotate.

Technical Field

The invention relates to a clamping system for frameless photovoltaic tiles.

Background

Solar energy is a new energy which is emphasized by the nation, and generally a crystalline silicon solar panel is utilized to generate electricity. As technology has evolved, frameless photovoltaic modules have also emerged, which to the skilled person do not have the frame of conventional modules. However, in the process of transporting, storing or transferring the frameless photovoltaic module, the corners of the frameless photovoltaic module are easily damaged by collision, so that the frameless photovoltaic module is easily subjected to subfissure.

Disclosure of Invention

In view of the above, there is a need for a frameless photovoltaic tile clamping system that is less prone to subfissure.

The clamping system comprises a clamping assembly and a frameless photovoltaic tile, wherein the clamping assembly comprises a clamping frame, two clamping frames and two turnover frames, a clamping slot is formed in the clamping frame, the two clamping frames are respectively and rotatably installed on the two opposite sides of the clamping frame, through grooves are formed in the two opposite ends of the clamping frame, the two turnover frames are respectively and rotatably installed on the two opposite ends of the clamping frame, the frameless photovoltaic tile is inserted into the clamping slot, the two clamping frames are respectively clamped on the two opposite sides of the frameless photovoltaic tile, and the two turnover frames are respectively used for being turned and clamped into the two through grooves so as to directly support and protect the corner of the frameless photovoltaic tile.

In one embodiment, the clamping frame comprises two clamping walls, the two clamping walls are arranged oppositely, the clamping slot is positioned between the two clamping walls, and the two clamping brackets are respectively arranged on the two clamping walls.

In one embodiment, the clamping frame comprises two deflection plates, a rotating shaft and a clamping structure, the two deflection plates are rotatably connected to the top of the clamping wall and are arranged at intervals, an exposed space is formed between the two deflection plates, two opposite ends of the rotating shaft are respectively connected to the tops of the two deflection plates, and the clamping structure is installed on the rotating shaft.

In one embodiment, the clamping structure comprises a connecting strip plate, two connecting sheets, a mandrel and a plurality of elastic wrapping rolls, the connecting strip plate is connected to the rotating shaft, the two connecting sheets are respectively and vertically arranged at two opposite ends of the connecting strip plate in a protruding mode, two opposite ends of the mandrel are respectively connected to the top ends of the two connecting sheets, and the plurality of elastic wrapping rolls are sequentially sleeved on the rotating shaft.

In one embodiment, the distance between the clamping structures of the two clamping frames gradually decreases along the vertical upward direction, and a gap is formed between every two adjacent elastic wraps.

In one embodiment, the through groove is positioned at the bottom of the end wall of the clamping frame, the through groove is communicated with the clamping slot, each roll-over stand comprises a pivot end and a retaining end which are oppositely arranged, the pivot end is rotatably connected to the top of the end wall of the clamping frame, and the retaining end is convexly provided with a flexible retaining block which is used for being clamped into the through groove.

In one embodiment, the sheet metal moving device further comprises a moving assembly, the moving assembly comprises a supporting plate, a sheet metal moving frame and two supporting studs, a long and narrow groove is formed in the center of the bottom of the clamping frame, an inlet groove is formed in the middle of the long and narrow groove, the inlet groove penetrates through the bottom surface of the clamping frame, the supporting plate supports against the bottom surface of the clamping frame, and the sheet metal moving frame is fixed on the supporting plate through the two supporting studs.

In one embodiment, a penetrating body is convexly arranged in the middle of the abutting plate, the penetrating body is arranged in the entering groove in a penetrating mode, an inserting plate is convexly arranged at the top end of the penetrating body, and the inserting plate is inserted into the elongated groove.

In one embodiment, the abutting plate is provided with two threaded holes, the metal plate moving frame is provided with two through holes, the two abutting studs are respectively arranged in the two through holes in a penetrating mode and are respectively screwed in the two threaded holes, and the end portion of the abutting stud abuts against the bottom face of the clamping frame.

In one embodiment, the two abutting studs are respectively located at two opposite sides of the two inlet slots, and two inlet holes are further formed in one side, away from the abutting plate, of the sheet metal moving frame and are respectively aligned with the two through holes for a screwdriver to enter to drive the abutting studs to rotate.

During installation, the frameless photovoltaic tile is inserted into the clamping slot, then the two clamping frames are used for clamping the two opposite sides of the frameless photovoltaic tile respectively, and then the two turning frames are turned over, so that the two turning frames are clamped into the two through slots respectively, and corners of the frameless photovoltaic tile are directly abutted and protected. The frameless photovoltaic tile is clamped and protected by the clamping system of the frameless photovoltaic tile, so that the corners of the frameless photovoltaic tile are not easy to collide to generate hidden cracks in the process of transporting, storing or transferring the frameless photovoltaic tile.

Drawings

Fig. 1 is a front view of a clamping system of a frameless photovoltaic tile of an embodiment.

Fig. 2 is a perspective view of the clamping system of the frameless photovoltaic tile of fig. 1.

Fig. 3 is a perspective view from another perspective of the clamping system of the frameless photovoltaic tile of fig. 2.

Fig. 4 is a partially enlarged view of a portion a in fig. 2.

Fig. 5 is a partially enlarged view of fig. 3 at B.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

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. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The invention relates to a clamping system for frameless photovoltaic tiles. For example, the clamping system for the frameless photovoltaic tile comprises a clamping assembly and the frameless photovoltaic tile, wherein the clamping assembly comprises a clamping frame, two clamping frames and two turning frames, and a clamping slot is formed in the clamping frame. For example, the two clamping frames are respectively and rotatably installed at two opposite sides of the clamping frame, through grooves are formed in two opposite ends of the clamping frame, the two turning frames are respectively and rotatably installed at two opposite ends of the clamping frame, and the frameless photovoltaic tile is inserted into the clamping slot. For example, two clamping brackets are clamped on opposite sides of the frameless photovoltaic tile. For example, two roll-over stands are respectively used for roll-over clipping into two through slots to directly abut against and protect the corners of the frameless photovoltaic tile.

Referring to fig. 1 to 5, a clamping system for frameless photovoltaic tiles includes a clamping assembly 40 and frameless photovoltaic tiles (not shown), the clamping assembly 40 includes a clamping frame 41, two clamping frames 42 and two turning frames 43, a clamping slot 411 is formed in the clamping frame 41, the two clamping frames 42 are respectively rotatably installed at opposite sides of the clamping frame 41, through slots 412 are respectively opened at opposite ends of the clamping frame 41, the two turning frames 43 are respectively rotatably installed at opposite ends of the clamping frame 41, the frameless photovoltaic tiles are inserted into the clamping slot 411, the two clamping frames 42 are respectively clamped at opposite sides of the frameless photovoltaic tiles, and the two turning frames 43 are respectively used for turning and being clamped into the two through slots 412 to directly abut against and protect corners of the frameless photovoltaic tiles.

During installation, the frameless photovoltaic tile is inserted into the clamping slot 411, then clamped on opposite sides of the frameless photovoltaic tile by the two clamping frames 42, and then the two roll-over frames 43 are turned over such that the two roll-over frames 43 are snapped into the two through slots 412, respectively, to directly abut against and protect the corners of the frameless photovoltaic tile. The frameless photovoltaic tile is clamped and protected by the clamping system of the frameless photovoltaic tile, so that the corners of the frameless photovoltaic tile are not easy to collide to generate hidden cracks in the process of transporting, storing or transferring the frameless photovoltaic tile.

For example, to facilitate clamping of frameless photovoltaic tiles, the clamping frame 41 comprises two clamping walls 413, the two clamping walls 413 being arranged opposite to each other, the clamping slot 411 being located between the two clamping walls 413, the two clamping frames 42 being mounted on the two clamping walls 413, respectively. The clamping frame 42 comprises two deflection plates 421, a rotation shaft 422 and a clamping structure 425, wherein the two deflection plates 421 are rotatably connected to the top of the clamping wall 413, the two deflection plates 421 are arranged at intervals, an exposed space 4215 is formed between the two deflection plates 421, two opposite ends of the rotation shaft 422 are respectively connected to the tops of the two deflection plates 421, and the clamping structure 425 is installed on the rotation shaft 422. The clamping structure 425 comprises a connecting lath 4251, two connecting pieces 4253, a mandrel 4254 and a plurality of elastic wrapping rolls 4255, wherein the connecting lath 4251 is connected to the rotating shaft 422, the two connecting pieces 4253 are respectively vertically and convexly arranged at two opposite ends of the connecting lath 4251, two opposite ends of the mandrel 4254 are respectively connected to the top ends of the two connecting pieces 4253, and the plurality of elastic wrapping rolls 4255 are sequentially sleeved on the rotating shaft 422. By providing the clamping frames 42 on the two clamping walls 413, the clamping structures 425 of the two clamping frames 42 can be utilized to clamp opposite sides of the frameless photovoltaic tile, improving the clamping stability. And the arrangement of a plurality of elastic wrappings 4255 can realize flexible clamping, and the frameless photovoltaic tile cannot be damaged by rigid clamping.

For example, to facilitate flexible retention against the corners of frameless photovoltaic tiles, the distance between the gripping structures 425 of two gripping brackets 42 gradually decreases in a vertically upward direction, with a gap formed between each adjacent two elastic wraps 4255. The through slot 412 is located at the bottom of the end wall of the holding frame 41, the through slot 412 is communicated with the holding slot 411, each roll-over stand 43 comprises a pivot end 431 and a retaining end 432 which are oppositely arranged, the pivot end 431 is rotatably connected to the top of the end wall of the holding frame 41, the retaining end 432 is convexly provided with a flexible retaining block 433, and the flexible retaining block 433 is used for being clamped into the through slot 412. By projecting a flexible retaining block 433 over the pivot end 431, the retaining block is snapped into the through slot 412 to retain the corner of the frameless photovoltaic tile.

For example, in order to facilitate clamping and moving the frameless photovoltaic tile, the clamping system of the frameless photovoltaic tile further includes a moving assembly 50, the moving assembly 50 includes a supporting plate 51, a metal plate moving frame 52 and two supporting studs 53, a long and narrow groove is formed in the center of the bottom of the clamping frame 41, the long and narrow groove and the clamping slot 411 are separated from each other, an entry groove is formed in the middle of the long and narrow groove, the entry groove penetrates through the bottom surface of the clamping frame 41, the supporting plate 51 supports against the bottom surface of the clamping frame 41, and the metal plate moving frame 52 is fixed on the supporting plate 51 through the two supporting studs 53. A penetrating body 515 is convexly arranged in the middle of the abutting plate 51, the penetrating body 515 is arranged in the entering groove in a penetrating mode, an inserting plate 516 is convexly arranged at the top end of the penetrating body 515, and the inserting plate 516 is inserted into the elongated groove. Two threaded holes are formed in the abutting plate 51, two through holes are formed in the sheet metal moving frame 52, two abutting studs 53 are respectively arranged in the two through holes in a penetrating mode and are respectively screwed in the two threaded holes, and the end portions of the abutting studs 53 abut against the bottom face of the clamping frame 41. The two abutting studs 53 are respectively located at two opposite sides of the two entering slots, two entering holes 521 are further formed in one side of the sheet metal moving frame 52 away from the abutting plate 51, and the two entering holes 521 are respectively aligned with the two passing holes for a screwdriver to enter to drive the abutting studs 53 to rotate. The inserting plate 516 is clamped into the elongated slot, the two abutting studs 53 are used for fixing the abutting plate 51 on the sheet metal moving frame 52, then the two abutting studs 53 abut against the bottom surface of the clamping frame 41 to force the abutting plate 51 to drive the inserting plate 516 to move away, and the inserting plate 516 and the two abutting studs 53 are used for fixing the clamping frame 41. The transfer unit 50 is attached to the holding frame 41, thereby facilitating the transfer operation of the holding frame 41.

For example, it is particularly important that the end wall of the clip frame 41 be upwardly projecting to form a projection 417 in order to facilitate guiding the insertion of frameless photovoltaic tiles into the clip slot 411. Opposite ends of the holding slot 411 extend into the two protrusions 417, respectively, and a lead-in groove 438 is opened at a side of the roll-over stand 43 facing away from the flexible holding block 433. The lead-in slots 438 are aligned with the clamping slots 411 when the roll-over stands 43 are not turned over, the lead-in slots 438 of the two roll-over stands 43 being used to guide frameless photovoltaic tiles into the clamping slots 411. Each holding wall 413 is provided with a sliding slot 4136, opposite ends of the sliding slot 4136 extend to the two protrusions 417 respectively, and the sliding slot 4136 is located on one side of the two deflection plates 421 away from the holding slot 411, that is, at the edge of the holding wall 413. The bottom of the two deflecting plates 421 is connected to the top of the clamping wall 413 by a torsion spring for forcing the two deflecting plates 421 to be maintained in a vertical direction. A stopper bar is protruded upward from the middle of the sliding slot 4136, and the stopper bar is located at the middle of the exposed space 4215. A through strip 4214 is further protruded from an edge of the deflection plate 421 adjacent to the protrusion 417.

For example, opposite sides of each end wall of the clamping frame 41 are recessed with mounting grooves, respectively. One side of the mounting groove is concavely provided with a strip-shaped groove. Each clamping wall 413 is further provided with a force application assembly 60, each force application assembly 60 comprises two force application plates 61, two force application ropes 62, two buckling blocks 63 and two abutting pieces 64, the two force application plates 61 are installed in the exposure space 4215 and located on two opposite sides of the stop bar respectively, a thickened portion 611 is formed on the upper portion of each force application plate 61, a narrow insertion plate 613 is formed on the bottom portion of each force application plate 61, and the narrow insertion plate 613 is slidably inserted into the sliding slot 4136. A plurality of elastic pulling ropes 614 are connected between the two force application plates 61. The ends of the two force application ropes 62 are respectively connected to the two force application plates 61, the middle parts of the force application ropes 62 are movably arranged in the corresponding through strips 4214, and one ends of the force application ropes 62 far away from the force application plates 61 are connected to the middle part of the roll-over stand 43 and are positioned above the protruding parts 417. The two pressing blocks 63 are movably installed in the installation grooves of the two protruding portions 417, respectively, an inclined surface 631 and a bottom surface 635 are formed on the pressing blocks 63, the distance between the inclined surface 631 and the side surface of the protruding portion 417 is gradually decreased in the vertical downward direction, the bottom surface 635 faces the ground, and the distance between the bottom surface 635 and the ground is gradually increased in the direction facing the stop bar. A strip-shaped slot 637 is concavely arranged on the bottom surface 635. One end and the bar draw-in groove 637 intercommunication in bar groove, the other end is worn to establish the extension of strip 4214 towards, and the extending direction in bar groove is parallel with the extending direction of bar draw-in groove 637. Each abutting part 64 comprises an abutting flat plate part 641 and a toggle strip 643 which is convexly arranged at the corner of the abutting flat plate part 641, the abutting flat plate part 641 is movably arranged at the top of the clamping wall 413 and is positioned between the convex part 417 and the deflection plate 421, the toggle strip 643 is movably clamped into the strip-shaped groove, and the end part of the toggle strip 643 is positioned in the strip-shaped clamping groove 637 and is provided with a return spring.

After the frameless photovoltaic tile is inserted into the clamping slot 411, the roll-over stand 43 is used for rolling over 180 degrees to drive the force application rope 62 to pull the force application plate 61 to move towards the protruding portion 417, the narrow insertion plate 613 slides along the sliding slot 4136 to enable the thickened portion 611 to move and abut against the deflection plate 421, the deflection plate 421 is forced to drive the clamping structure 425 to abut against the frameless photovoltaic tile until the side wall of the force application plate 61 abuts against the through strip 4214, and the flexible retaining block 433 is clamped into the through groove 412. In the process, the force application rope 62 is used for moving to the buckling and pressing block 63 from above the inclined surface 631 along with the roll-over stand 43, so as to force the buckling and pressing block 63 to retract into the installation groove, and the buckling and pressing block 63 presses the abutting part 64 to abut against the surface of the frameless photovoltaic tile, so that the middle part of the force application rope 62 is allowed to move to the abutting flat plate part 641 from above the abutting flat plate part 641 to keep the abutting flat plate part 641 abutting against the frameless photovoltaic tile. The force application cord 62 is also used to release the button block 63 after disengaging below the button block 63 to allow the button block 63 to spring up so that the force application cord 62 snaps into the strip-shaped slot 637. In the buckling block 63, the middle portion of the force application rope 62 is always kept on the abutting flat plate portion 641, and the abutting state of the abutting flat plate portion 641 is inconvenient. For example, the force application cord 62 has a certain elasticity.

For example, in one embodiment, the buckling block 63 is a button that is pressed twice, the buckling block 63 is pressed by the force applying rope 62 for the first time to drive the abutting member 64 to move, the buckling block 63 is sprung after the force applying rope 62 is moved downwards and the buckling block 63 is released, after the force applying rope 62 is clamped in the bar-shaped clamping slot 637, the force applying rope 62 can be clamped by pressing the buckling block 63 with a hand, and then the pressing button is not sprung any more. Specifically, the structure of the secondary button pressing is a common technical means in the field, and is not described again. The force application rope occupied by the turnover frame is longer after turnover, so that the force application rope can enable the force application plate to be kept on the deflection plate.

By providing a plurality of elastic pulling ropes 614, the shielding effect of the exposed space 4215 can be maintained after the two force applying plates 61 leave, the two force applying plates 61 can apply force to force the two deflecting plates 421 to drive the clamping structure 425 to clamp the frameless photovoltaic tile, and the force applying rope 62 drives the abutting piece 64 to move at the driving buckling block 63, so that the force applying rope 62 can smoothly reach the surface of the abutting flat plate portion 641 to maintain the abutting state of the abutting flat plate portion 641. In addition, the inclined surface 631 of the pressing block 63 facilitates the movement of the force application cord 62 over and into the strip-shaped slot 637, and the pressing block 63 can also be pressed by a human hand to clamp the force application cord 62. As another function, the end of the force application cord 62 can tension the roll-over stand 43 so that the flexible retaining block 433 remains tucked into the through slot 412. One function of the through-hole 4214 is to ensure the direction of the force application rope 62, and the other function is to stop the transverse movement of the force application plate 61. When the frameless photovoltaic tile needs to be released, the force application rope 62 is pulled down by one hand to be separated from the strip-shaped clamping groove 637, the pressing block 63 is pressed by the other hand, the force application rope 62 is pulled to move towards the inclined surface 631, then the overturning frame 43 is reversed, and then the elastic pull ropes 614 can assist in returning by utilizing elastic force.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present 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. Therefore, the protection scope of the present patent shall be subject to the appended claims.