TWM643329U - connector assembly - Google Patents

Abstract

A connector assembly includes a guiding shield, a light guide and an assembly structure of the light guide. The guiding shield includes a top wall, a side wall, a bottom wall, and a support plate extending from the bottom wall and located outside the side wall. The light guide is disposed outside the side wall of the guide shield and is upwardly supported by the support plate. The assembly structure of the light guide includes a first buckle structure and a second buckle structure; the first buckle structure is arranged between the light guide member and the support plate extending from the bottom wall; the second buckle structure is arranged between the light guide member and the top wall.

Description

connector assembly

The present invention relates to a connector assembly, in particular to a connector assembly with a light guide.

Chinese Invention Patent No. CN110364871B (corresponding to U.S. Patent No. US10950983B2) discloses that a buckle structure is formed on the side wall of the housing and the light guide tube. The buckle structure includes a first buckle structure suitable for vertically positioning multiple light guide tubes and a second buckle structure suitable for horizontally positioning multiple light guide tubes; The fastener has a first C-shaped slot suitable for being clamped on the first connecting column; the second buckling structure includes: a second connecting column extending vertically and connected between two adjacent light pipes; and a second fastener having a second C-shaped slot suitable for being clamped on the second connecting column.

However, the above-mentioned first buckle and second buckle are stamped parts formed by stamping the side wall of the housing, that is, a plurality of holes need to be punched on the housing to form the buckle, and these openings will reduce the electromagnetic interference suppression effect of the housing. In addition, the buckle and the connecting column are only fastened through the C-shaped slot, and the strength of the assembled structure is insufficient and unstable. Furthermore, the light pipe needs to be assembled or disassembled laterally, and space needs to be reserved on the side of the housing. When it is applied to the combination of multiple guide shields side by side, the lateral arrangement spacing of the guide shields needs to be increased to allow enough space for the light pipe to be assembled or disassembled sideways; even in some cases, the light pipe is assembled before the guide shields are arranged side by side.

Therefore, one purpose of the present invention is to provide a connector assembly that can solve at least one problem of the prior art.

Therefore, in some embodiments of the present invention, the connector assembly includes a guiding shield, a light guide, and an assembly structure of the light guide. The guiding shield includes a top wall, a side wall, a bottom wall, and a support plate extending from the bottom wall and located outside the side wall. The light guide is disposed outside the side wall of the guide shield and is upwardly supported by the support plate. The assembly structure of the light guide includes a first buckle structure and a second buckle structure; the first buckle structure is arranged between the light guide member and the support plate extending from the bottom wall; the second buckle structure is arranged between the light guide member and the top wall.

In some implementation aspects, the guide shield further includes a side plate extending from the bottom wall and located on the outside of the side wall, the support plate is a plate integrally extending laterally from the side plate and located on the outside of the side wall, the plate surface of the support plate faces upward; the first buckle structure includes a first buckle block buckled on the support plate, and the first buckle block is constructed on the light guide; It can be seen that the plate surface of the supporting tab faces sideways, the second fastening block is configured on the light guide, and the second fastening block is fastened on the supporting tab.

In some implementation aspects, the support plate has an opening, the first fastening block has a fastening slot with an opening facing backward, and the first fastening block passes through the opening of the support plate, so that the fastening slot can be pushed backward and fastened on the support plate.

In some implementation aspects, the light guide includes a plurality of light guide pipes and a first connecting rod connecting the light pipes, the first fastening block extends downward from the first connecting rod, the first fastening block has a lower buckle block, and the fastening slot formed between the lower buckle block and the first connecting rod, the first connecting rod is upwardly supported by the support plate, and the side plate supports the light guide upward through the support plate and the first connecting rod.

In some implementation aspects, the light guide member further includes a second connecting rod connecting the light pipes, and the second fastening block extends from the second connecting rod toward the inner side and toward the guiding shield.

In some implementation aspects, the support lug has a constriction-shaped snapping recess that opens upward, the second fastening block has a constricted portion, and the constricted portion of the second fastening block snaps downward and is snapped into the snapping notch of the support lug.

In some implementation aspects, the guide shield includes an upper shell and a lower shell, the upper shell includes the top wall and two side walls, the lower shell includes the bottom wall and two side plates extending upward from both sides of the bottom wall, the two side plates are respectively located on the outer surfaces of the two side walls and are fastened to the two side walls respectively.

In some implementation aspects, the light guide is arranged on the outer side of one of the side walls and is supported upward by the support plate on the corresponding one of the side plates. The light guide includes a plurality of light guides and a plurality of connecting rods. The light guides are arranged at intervals from top to bottom in a plane substantially parallel to the side walls. Each light guide has a forward section located in front and extending forward, a downward section located behind and extending downward, and a curved section located between the forward section and the downward section. The light pipes are connected to each other through the connecting rods. The connecting rods include a first connecting rod extending forward and backward and connected between the down-extending sections, and a second connecting rod extending up and down and connected between the forward-extending sections. The first fastening block extends downward from the first connecting rod, and the second fastening block extends inwardly from the second connecting rod and toward the guiding shield.

In the present invention, the support plate extending from the bottom wall can support the light guide upwards, and the light guide is fixed on the support plate and the top wall through the assembly structure of the light guide at the same time, the assembly operation is easy and the light guide can be stably and reliably fixed. In addition, the light guide pipe is arranged on the outer side of the side wall, and can be assembled and disassembled front-to-rear and up-and-down, so as to save the occupied space in the side direction. Especially in the application where multiple connector components are arranged side by side, the saved lateral space can make the guide shields of multiple connector components be arranged in a compact manner, and avoid disassembly and assembly of the light pipe after the guide shields of multiple connector components are arranged and set. Furthermore, the side wall of the guiding shield does not need to be provided with a structure for assembling the light guide, so there is no need to add openings on the side wall for this purpose, thereby further increasing the electromagnetic interference suppression effect of the guiding shield.

Referring to FIG. 1 to FIG. 3 , an embodiment of the connector assembly 100 of the present invention is suitable for being disposed on a circuit board (not shown in the figure) and suitable for plugging with a pluggable module 200 . The pluggable module 200 has a shell 201 , a circuit board 202 and a cable 203 . The housing 201 has a plugging portion 201a, the plugging circuit board 202 is disposed at the front end of the plugging portion 201a, and the cable 203 is disposed at the rear end of the housing 201 and is electrically connected to the plugging circuit board 202 . The connector assembly 100 includes a guide shield 1 , a receptacle connector 2 , a heat sink 3 , a buckle 4 , a light guide 5 , and a light guide assembly structure 6 .

The guide shield 1 is, for example, constructed by stamping and bending a thin metal plate, and the guide shield 1 is used to be disposed on the circuit board. The guide shield 1 has a top wall 11 and a bottom wall 12 spaced apart along a vertical direction D1 (the direction of the arrow is upward, and the direction of the reverse is downward), two side walls 13 spaced apart along a left-right direction D2 (the direction of the arrow is right, and the direction of the reverse is left), two side plates 14 extending from the bottom wall 12 and respectively located outside the two side walls 13, integrally extending laterally from one of the side plates 14 along the left-right direction D2 and positioned outside the corresponding side wall 13. A support plate 611 , a rear wall 15 located at the rear end along a front-to-back direction D3 (arrow direction is front, reverse direction is rear), and an insertion channel 16 is located inside. The lower edges of the side walls 13 are configured with a plurality of pins 17 extending downward and adapted to be fixed on the circuit board and/or connected to a ground trace (not shown). The insertion channel 16 has a front socket 161 facing forward for the insertion portion 201 a of the pluggable module 200 to be inserted into, and a bottom opening 162 at the rear of the bottom.

In the first embodiment, the guiding shield 1 includes an upper shell 1a and a lower shell 1b assembled with each other and configuring the insertion channel 16 . The upper casing 1a has the top wall 11 and the side walls 13 integrally connected with each other, a plurality of buckle blocks 131 formed on the side walls 13 near the lower edge and protruding outward, and two dovetail recesses 132 respectively formed on the bottom edges near the front ends of the side walls 13. The lower housing 1b has the bottom wall 12, the two side plates 14 integrally extending upward from both sides of the bottom wall 12, a plurality of button holes 141 formed on the two side plates 14 and corresponding to the buckle blocks 131 of the two side walls 13, and two dovetail protrusions 18 integrally formed upward from the near front end of the bottom wall 12 and corresponding to the dovetail recesses 132 of the two side walls 13. The two side panels 14 of the lower casing 1b are respectively located on the outer surfaces of the two sidewalls 13 of the upper casing 1a, and the button holes 141 of the two side panels 14 are fastened to the buckle blocks 131 of the two sidewalls 13, so that the bottom wall 12 of the lower casing 1b can be assembled and combined with the two sidewalls 13 of the upper casing 1a.

The top wall 11 of the guide shield 1 has a window 111 communicating with the insertion channel 16 , a guide portion 112 extending downward from a rear portion of one side of the window 111 into the insertion channel 16 , and a stop portion 113 extending downward from the rear end of the window 111 into the insertion channel 16 . Each of the sidewalls 13 of the guide shield 1 has two fastening blocks 133 near the upper edge, and an inwardly extending elastic piece 134 at the front.

The guide shield 1 is assembled with a plurality of grounding elements 19 around the front socket 161 . In this embodiment, the guide shield 1 of the connector assembly 100 can be disposed in a mounting hole (not shown) of a housing (not shown), each ground member 19 has a plurality of elastic portions 191 extending backward and distributed on the outside and inside of the guide shield 1 , the outer elastic portions 191 are used to contact with the surrounding portion of the installation hole of the housing, and the inner elastic portions 191 are used to contact the pluggable module 200 .

The receptacle connector 2 is arranged on the circuit board, and the guiding shield 1 accommodates the receptacle connector 2 at the rear section of the insertion channel 16 through the bottom opening 162 . The receptacle connector 2 has an insulated housing 21, and a plurality of terminals 22 disposed on the housing 21. The housing 21 has a pair of mating slots 211 inserted into the plugging circuit board 202 of the pluggable module 200. Each of the terminals 22 has a contact portion 221 located in the mating slot 211, and a tail portion (not shown) extending downward from the bottom of the housing 21. The tails of the terminals 22 are respectively used for soldering to solder pads on the circuit board. (not shown) to connect to conductive traces (not shown) on the circuit board.

The inserting portion 201a of the pluggable module 200 has two locking grooves 201b on the left and right sides, a guiding groove structure 201c on the top of the front end, and an alignment structure 201d on the top. The inwardly extending elastic pieces 134 on the side walls 13 of the guiding shield 1 are used to cooperate with the locking groove 201b of the pluggable module 200 inserted into the insertion channel 16 to produce a locking effect. The guide portion 112 is used for inserting into the guide groove structure 201c of the pluggable module 200 to generate a guide function. The stop portion 113 is used to stop the alignment structure 201d of the pluggable module 200 to limit the insertion position of the pluggable module 200 . In addition, the pluggable module 200 also has an unlocking member 204, and when the unlocking member 204 is pulled, the inwardly extending elastic piece 134 can be pushed out from the locking groove 201b.

The buckle 4 is used to assemble the heat sink 3 to the top wall 11 of the guiding shield 1 of the guiding shield 1 to move up and down. The heat sink 3 has a base plate 31, a thermal coupling portion 32 located at the bottom of the base plate 31 and capable of extending into the insertion channel 16 through the window 111, a plurality of cooling fins 33 located at the top of the base plate 31, and two grooves 34 formed between the cooling fins 33 and extending laterally along the left-right direction D2. Wherein, although in the present embodiment, the heat dissipation fins 33 are a plurality of heat dissipation plates interlocked with each other and are arranged on the top surface of the substrate 31 by welding, for example, in a variant embodiment, the heat dissipation fins 33 can also be integrally constructed on the substrate 31.

The thermal coupling portion 32 of the heat sink 3 is used to contact the pluggable module 200 inserted into the insertion channel 16 , thereby enhancing the heat dissipation performance of the heat sink 3 . In this embodiment, the thermal coupling part 32 includes a heat conduction pad (not shown) located at the bottom and used to contact the pluggable module 200, the heat conduction pad can fill the seams or gaps on the contact surface, reduce the contact thermal resistance between the contact surfaces, and increase the heat conduction efficiency. The thermal pad is, for example, a thermal interface material. The thermal interface material can be selected from a combination of materials with properties such as high thermal conductivity, high flexibility, compressibility, insulation, wear resistance, etc., or can be selected from a combination of a base material and a phase change material.

The buckle 4 is non-removably assembled to the guiding shield 1 . The buckle 4 has two left and right fastening parts 41 and two spring parts 42 connected between the two fastening parts 41 . Each of the spring parts 42 has two connecting arms 421 located at left and right ends and extending obliquely upwards and outwards. The two connecting arms 421 are respectively connected to the two fastening parts 41 . Each fastening portion 41 has two fastening holes 411 fastened to the two fastening blocks 133 of the corresponding sidewall 13 , and the spring portion 42 is accommodated in the groove 34 of the heat sink 3 and exerts elastic force on the heat sink 3 downward.

Referring to FIG. 2 to FIG. 5 , the light guide 5 is disposed on the outer side of one of the side walls 13 of the guiding shield 1 and supported upward by the supporting plate 611 on the corresponding one of the side plates 14 on the same side. The light guide member 5 includes a plurality of light guide pipes 51 and a plurality of connecting rods 52 . The light pipes 51 are arranged at intervals from top to bottom in a plane substantially parallel to the side wall 13 . Each light pipe 51 has a forward section 511 extending forward, a downward section 512 backward and downward, and a curved section 513 between the forward section 511 and the downward section 512 . A light incident end 512a at the end of the downward extension 512 of each light pipe 51 is used to face the light-emitting element (not shown) on the circuit board and receive the light emitted by the light-emitting element, and a light-emitting end 511a at the end of the forward extension 511 of each light guide 51 is used to send the light of the light-emitting element forward. The light pipes 51 are connected to each other through the connecting rods 52 . The connecting rods 52 include a plurality of first connecting rods 521 extending forward and backward and connected between the downward extending sections 512 of the light guide pipes 51 , and a plurality of second connecting rods 522 extending up and down and connecting between the forward extending sections 511 of the light guiding pipes 51 .

The light guide assembling structure 6 is used for assembling the light guide 5 to the guiding shield 1 , and the light guide assembling structure 6 includes a first buckling structure 61 and a second buckling structure 62 . The first fastening structure 61 is relatively located at the bottom and rear, and the second fastening structure 62 is relatively located at the top and front.

Referring to FIG. 2 to FIG. 6 , the first fastening structure 61 is disposed between the light guide member 5 and the supporting plate 611 on the corresponding side plate 14 extending from the bottom wall 12 of the lower casing 1b. The first fastening structure 61 includes a first fastening block 612 .

A surface of the support plate 611 faces upward and is substantially perpendicular to the side plate 14 , and the support plate 611 has an opening 611 a facing forward. The first fastening block 612 is configured on the light guide member 5 , and the first fastening block 612 extends downward from one of the first connecting rods 521 . The first locking block 612 has a lower locking block 612a, and a locking groove 612b formed between the lower locking block 612a and the first connecting rod 521 and opening to the rear. The first fastening block 612 can pass through the opening 611 a of the support plate 611 downwards, so that the fastening slot 612 b of the first fastening block 612 can move backward and be fastened on the support plate 611 . In addition, the left and right sides of the opening 611 a of the support plate 611 can limit the movement of the first fastening block 612 in the left-right direction D2 .

Referring to FIG. 2 to FIG. 4 and FIG. 7 , the second fastening structure 62 is disposed between the light guide member 5 and the top wall 11 of the upper casing 1a. The second fastening structure 62 includes a supporting tab 621 and a second fastening block 622 . The support tab 621 is integrally constructed from the top wall 11. Specifically, the support tab 621 is located at the top wall 11 near the side wall 13 and protrudes upward from the top wall 11. The support tab 621 is a sheet cut from the top wall 11 of the upper casing 1a and bent upward, and the plate surface of the support tab 621 faces sideways. The supporting protruding piece 621 has a constricted engaging recess 621 a opening upward.

The second fastening block 622 is configured on the light guide member 5 , and the second fastening block 622 is formed to extend from one of the second connecting rods 522 toward the inner side and toward the guiding shield 1 . The second fastening block 622 has a constricted portion 622a corresponding to the engaging notch 621a , the constricted portion 622a of the second fastening block 622 can be snapped downward into the engaging notch 621a of the supporting tab 621 .

Referring to FIG. 8 and FIG. 9 , during the assembly process, the light guide member 5 is first tilted slightly backward and downward, and the first fastening block 612 is inserted downward into the opening 611a of the support plate 611, and then the first fastening block 612 is pushed backward, so that the fastening groove 612b of the first fastening block 612 is fastened on the support plate 611.

Referring to FIG. 10 and FIG. 11 , then press down the second fastening block 622, so that the constricted portion 622a of the second fastening block 622 is fastened in the engaging notch 621a of the supporting lug 621, and at this time, the light guide 5 returns to its normal state from the tilted state and completes the assembly. In general, the assembling operation of the light guide member 5 is basically completed by the operations of "pushing back" and "pressing downward". Referring to FIG. 1 and FIG. 2 , after the assembly is completed, the first connecting rod 521 is upwardly supported by the supporting plate 611 , and the side plate 14 supports the light guide 5 upwardly through the supporting plate 611 and the first connecting rod 521 .

In summary, the support plate 611 extending from the bottom wall 12 in the present invention can support the light guide 5 upwards, and the light guide 5 is fixed on the support plate 611 and the top wall 11 through the light guide assembly structure 6 at the same time, the assembly operation is easy and the light guide 51 can be stably and reliably fixed. In addition, the light pipe 51 is disposed on the outside of the side wall 13 and can be assembled and disassembled front-to-rear and up-and-down, so as to save the occupied space on the side. Especially in the application where a plurality of connector assemblies 100 are arranged side by side, the saved lateral space can make the guide shields 1 of the plurality of connector assemblies 100 arranged compactly, and avoid disassembly and assembly of the light pipe 51 after the arrangement of the guide shields 1 of the plurality of connector assemblies 100 is completed. Moreover, the side wall 13 of the guiding shield 1 does not need to be provided with a structure for assembling the light guide 51 , so there is no need to add an opening in the side wall 13 for this purpose, thereby further increasing the electromagnetic interference suppression effect of the guiding shield 1 .

But the above-mentioned ones are only embodiments of the present model, and should not limit the scope of the present model implementation. All simple equivalent changes and modifications made according to the scope of the patent application for the present model and the contents of the patent specification are still within the scope covered by the patent of the present model.

100:Connector assembly 1: Guidance shield 1a: Upper shell 1b: Lower shell 11: top wall 111: window 112: Guidance department 113: stop part 12: Bottom wall 13: side wall 131: buckle block 132: Dovetail recess 133: buckle block 134: Internal shrapnel 14: side panel 141: buttonhole 15: rear wall 16: plug channel 161: front socket 162: bottom opening 17: Pin 18: Dovetail convex part 19: Grounding piece 191: elastic part 2: socket connector 21: Shell 211: Docking slot 22: terminal 221: contact part 3: Radiator 31: Substrate 32: thermal coupling part 33: cooling fins 34: Groove 4: Buckle 41: Fastening part 411: button hole 42: spring part 421: connecting arm 5: Light guide 51: Light pipe 511: Forward extension 511a: light output end 512: down extension 512a: light incident end 513: Bending section 52: connecting rod 521: the first connecting rod 522: the second connecting rod 6: Light guide assembly structure 61: The first fastening structure 611: support plate 611a: opening 612: The first fastening block 612a: Lower buckle block 612b: Fastening groove 62: Second fastening structure 621: Support tab 621a: Snap notch 622: The second fastening block 622a: shrink neck 200: pluggable module 201: shell 201a: socket part 201 b: locking groove 201 c: Guide groove structure 201d: Parapositional Structures 202: plug circuit board 203: cable 204: unlocking piece D1: up and down direction D2: left and right direction D3: Front and rear directions

Other features and functions of the present invention will be clearly presented in the implementation manner with reference to the drawings, wherein: Fig. 1 is a perspective view of an embodiment of the new connector assembly and a pluggable module; Fig. 2 is a three-dimensional exploded view of this embodiment; Fig. 3 is a further three-dimensional exploded view of this embodiment; Fig. 4 is a perspective view of a light guide of this embodiment; Fig. 5 is a partially enlarged perspective view of the lower casing of a guiding shield of the embodiment in Fig. 3, used to illustrate a support plate extending from a side plate of the guiding shield; 6 is a partial enlarged perspective view of the light guide of this embodiment, used to illustrate a first fastening block constructed on the light guide; 7 is another partially enlarged perspective view of the light guide of this embodiment, used to illustrate a second fastening block constructed on the light guide; Fig. 8 is a partial perspective view of the guiding shield and the light guide member of the embodiment, in which the first fastening block has not been fastened to the support plate; Fig. 9 is a partially enlarged perspective view of the guiding shield and the light guide member of the embodiment, in which the first fastening block is fastened to the support plate; FIG. 10 is a perspective view of the guiding shield and the light guide member of the embodiment, in which the second fastening block has not been fastened to a support tab constructed from a top wall of the guiding shield; FIG. 11 is a perspective view of the guiding shield and the light guide member of the embodiment, in which the second fastening block is fastened to the supporting tab formed from the top wall of the guiding shield.

100:Connector assembly

1: Guidance shield

1a: Upper shell

1b: Lower shell

11: top wall

111: window

112: Guidance department

113: stop part

12: Bottom wall

13: side wall

131: buckle block

132: Dovetail recess

133: buckle block

134: Internal shrapnel

14: side panel

141: buttonhole

15: rear wall

16: plug channel

17: Pin

18: Dovetail convex part

5: Light guide

51: Light pipe

511: Forward extension

511a: light output end

512: down extension

512a: light incident end

513: Bending section

52: connecting rod

521: the first connecting rod

522: the second connecting rod

6: Light guide assembly structure

61: The first fastening structure

611: support plate

611a: opening

62: Second fastening structure

621: Support tab

621a: Snap notch

622: The second fastening block

D1: up and down direction

D2: left and right directions

D3: Front and rear directions

Claims (8)

A connector assembly comprising: The guiding shield includes a top wall, a side wall, a bottom wall, and a support plate extending from the bottom wall and located outside the side wall; a light guide disposed outside the side wall of the guide shield and supported upward by the support plate; and The assembly structure of the light guide includes a first buckle structure and a second buckle structure; the first buckle structure is arranged between the light guide member and the support plate extending from the bottom wall; the second buckle structure is arranged between the light guide member and the top wall. The connector assembly according to claim 1, wherein the guiding shield further includes a side plate extending from the bottom wall and positioned outside the side wall, the support plate is a plate integrally extending laterally from the side plate and positioned outside the side wall, the plate surface of the support plate faces upward; the first buckle structure includes a first buckle block buckled on the support plate, and the first buckle block is configured on the light guide member; the second buckle structure includes a support lug and a second buckle block, and the support lug is integrated Constructed from the top wall, the plate surface of the support tab faces sideways, the second fastening block is constructed on the light guide, and the second fastening block is fastened to the support tab. The connector assembly according to claim 2, wherein the support plate has an opening, the first fastening block has a fastening groove with an opening facing backward, and the first fastening block passes through the opening of the support plate, so that the fastening groove can be pushed backward and fastened on the support plate. The connector assembly according to claim 3, wherein the light guide member includes a plurality of light guide pipes, and a first connecting rod connecting the light guide pipes, the first fastening block extends downward from the first connecting rod, the first fastening block has a lower buckle block, and the fastening groove formed between the lower buckle block and the first connecting rod, the first connecting rod is upwardly supported by the support plate, and the side plate supports the light guide upwardly through the support plate and the first connecting rod. The connector assembly according to claim 4, wherein the light guide further includes a second connecting rod connecting the light pipes, and the second fastening block extends from the second connecting rod toward the inner side and toward the guiding shield. The connector assembly according to any one of claim 2 to claim 5, wherein the support lug has a constriction-shaped snap-in recess that opens upward, the second fastening block has a constricted portion, and the constricted portion of the second fastening block snaps downward and is snapped into the snap-fit notch of the support lug. The connector assembly according to claim 2, wherein the guiding shield includes an upper housing and a lower housing, the upper housing includes the top wall and two side walls, the lower housing includes the bottom wall and two side plates extending upward from both sides of the bottom wall, the two side plates are respectively located on the outer surfaces of the two side walls and are fastened to the two side walls. The connector assembly according to claim 7, wherein the light guide is arranged on the outside of one of the side walls and is supported upward by the support plate on the corresponding one of the side plates, the light guide includes a plurality of light guides and a plurality of connecting rods, the light guides are arranged at intervals from top to bottom in a plane substantially parallel to the side walls, each light guide has a forward section located in front and extending forward, a downward section located behind and extending downward, and a section between the forward section and the downward section. The curved section and the light pipes are connected to each other through the connecting rods. The connecting rods include a first connecting rod extending forward and backward and connected between the down-extending segments, and a second connecting rod extending up and down and connected between the forward-extending segments. The first fastening block extends downward from the first connecting rod, and the second fastening block extends from the second connecting rod toward the inside and toward the guiding shield.

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