CN202472044U

CN202472044U - Socket connector and plug connector

Info

Publication number: CN202472044U
Application number: CN2011205532834U
Authority: CN
Inventors: 孙正国; 王继超; 郑启升
Original assignee: Foxconn Kunshan Computer Connector Co Ltd; Hon Hai Precision Industry Co Ltd
Current assignee: Foxconn Kunshan Computer Connector Co Ltd; Hon Hai Precision Industry Co Ltd
Priority date: 2011-12-27
Filing date: 2011-12-27
Publication date: 2012-10-03
Anticipated expiration: 2021-12-27

Abstract

Provided is a socket connector having an accepting space for accepting a plug connector. The socket connector comprises a socket body, a plurality of socket terminals accepted inside the socket body, and a fiber module group, wherein the socket body is provided with a socket lingual plate extending forward into the accepting space; the socket terminals comprise contact parts arranged upon the socket lingual plate and exposed to the accepting space to contact with the plug connector and a weld part extending outside the socket body; the fiber module group comprises an insulating pedestal assembled inside the socket body and a plurality of first lenses arranged upon the pedestal and exposed to the accepting space; the pedestal is further provided with a positioning column that extends forward to cooperate with the plug connector; and the positioning column is located between two adjacent first lenses.

Description

Socket connector and pin connector

[technical field]

The utility model relates to a kind of socket connector and pin connector with optical fiber module.

[background technology]

At the end of Year 2008; USB association has issued the USB standard of 3.0 versions, and this kind USB 3.0 connectors are on the basis of original USB 2.0 connectors, to increase to be provided with two pairs of difference signal terminal and a ground terminal in order to improve the transfer rate of original USB2.0 connector.The transfer rate of this kind USB 3.0 connectors can reach the 5G per second, and can peg graft simultaneously USB 2.0 and USB 3.0 connectors.Yet, because conducting terminal quantity is more on USB 3.0 connectors, make that the cable inner structure be connected in USB 3.0 connector rear sides is complicated, problem such as the heavier and high frequency of cable and make it the longlyest only can be provided with 5 meters, inconvenient consumer uses.In addition, the transmission speed of USB 3.0 connectors still can not satisfy the transmission demand of high capacity electronic equipments such as similar blue-ray DVD.

For overcoming the problems referred to above, optical fiber is widely used in the telecommunications field gradually, replaces wire rope can reach low-loss, remote, the low laser propagation effect that disturbs through optical fiber.Thus; But but connector manufacturers respectively increase by an optical fiber module to form the socket connector and the pin connector of a kind of not only transmitting optical signal but also transmission of electric signals on the basis based on USB socket connector and USB plug connector; Related art can be consulted a kind of socket connector that Dec 08, disclosed Chinese patent CN was disclosed for 101908679A number in 2010; It comprises jack body, is located at the some female terminals on the said jack body and is located at the optical fiber module on the said jack body; Said jack body comprises first body and is assembled in second body on first body that said optical fiber module is installed in first body, wherein; Said optical fiber module front end each side is provided with a pair of lens, and each arranged outside to lens has a reference column.In this structure, reference column can not accurately be guided this socket connector and docked with pin connector.

So be necessary to provide a kind of have structure improved socket connector and pin connector, to overcome above-mentioned defective.

[utility model content]

The utility model technical matters to be solved is to provide a kind of the have socket connector of optical fiber module and the pin connector that matches with this socket connector.

For solving the problems of the technologies described above, the utility model adopts following technical scheme: a kind of socket connector, be provided with in order to accommodate the receiving space of a pin connector, and it comprises jack body, is contained in some female terminals and optical fiber module in the jack body.Said jack body is provided with the socket hyoplastron that extends forwardly in the said receiving space, and female terminal comprises that row is located on the socket hyoplastron and is exposed to said receiving space with contact site that contacts with pin connector and the weld part that extends jack body.Said optical fiber module comprises and is assembled in the insulating base in the jack body and is located on the pedestal and is exposed to some first lens of said receiving space; Said pedestal also is provided with and extends the reference column that matches in order to pin connector forward, and said reference column is between adjacent two first lens.

In preferred embodiment, said jack body comprises first body and is assembled in second body on first body, and said first body comprises first base portion and first hyoplastron that extends forward from first base portion, and said optical fiber module is assembled on first body.

In preferred embodiment; Said first base portion comprises roof on the top, enclose the holding slot that forms at the diapire of bottom, in the two lateral walls of both sides, below being connected dividing plate between the two side, being enclosed the accepting groove that forms by roof, two side and dividing plate and being positioned at accepting groove by diapire, two side and dividing plate; Dividing plate separates holding slot and accepting groove, and said optical fiber module is assembled in forward in the said accepting groove.

In preferred embodiment; The pedestal front end face of said optical fiber module each side is provided with a pair of said first lens; Each is to being provided with a said reference column between first lens, the thin rear end of said reference column front end is thick, is formed with square convex tendon on the surface in the two reference columns outside.

In preferred embodiment; The transmission standard of conformance with standard USB 3.0 socket connectors of arranging of said female terminal; Said female terminal is contained in second body; Second body is assembled in forward in the said holding slot, and said optical fiber module also comprises and carries out the optical fiber of optically-coupled with said first lens and be fixed on the said pedestal to locate the collets of this optical fiber.

For solving the problems of the technologies described above, the utility model also can adopt following technical scheme: a kind of pin connector, in order to connect with socket connector, it comprises header body, is located at plug terminal and fiber device on the header body.Said header body is provided with extends forward to be contained in the plug hyoplastron in the socket connector; Plug terminal is provided with row and is located at the junction surface on the said plug hyoplastron; Fiber device comprise be assembled on the said plug hyoplastron and can before and after the insulation slide block that slides and be located at some second lens on the slide block; Said slip front face is concaved with the pilot hole that matches in order to socket connector, and said pilot hole is between adjacent two second lens.

In preferred embodiment; The locating convex block that said plug hyoplastron comprises the mounting groove, the holding tank that is positioned at the mounting groove rear that are positioned at the upper surface front end, be positioned at mounting groove the place ahead and a front wide and rear narrow roughly V-shaped stop block that upwards protrudes out and be positioned at holding tank, said slide block is installed in the mounting groove.

In preferred embodiment, said slide block also is provided with between two pilot holes and matches with stop block and front wide and rear narrow " V " shape depression, be located at the positioning convex column of rear end face and be positioned at the pilot hole lateral and extend out the square expansion slot that spread becomes.

In preferred embodiment; Said fiber device also comprises the spring that is clamped between header body and the fiber device, is fixed in the loam cake of slider bottom in order to fixed fiber; Said spring one end is socketed on the positioning convex column; The other end is socketed on the locating convex block, can in mounting groove, slide front and back at the spring action sliding block.

In preferred embodiment; Said pin connector also comprises the stationary installation that is retained on the header body; This stationary installation comprises locating piece and is installed on the bonnet on the locating piece forward; Locating piece is provided with " T " shape conduit that locating piece is run through in some front and back, convexes with on the bonnet front end face that " T " shape of buckle is protruding mutually with said conduit, the transmission standard of conformance with standard USB 3.0 pin connectors of arranging of said plug terminal; Said plug terminal is provided with first junction surface, second junction surface and is fixed on second connecting portion in the conduit; Convexity was pressed on downwards on second connecting portion after said bonnet was installed on the locating piece, limited second connecting portion and in conduit, rocked, and said first junction surface and second junction surface are positioned at the below of plug hyoplastron jointly and form two rows that arrange in front and back.

Compared with prior art; The utlity model has following beneficial effect: the optical fiber module of the utility model socket connector is provided with reference column; The pin connector fiber device be provided with in order to socket connector on the pilot hole that matches of reference column; Thereby guaranteed the center line complete matching of pin connector and socket connector, guaranteed the optical signal transmission quality.

[description of drawings]

Fig. 1 is the schematic perspective view of the utility model socket connector and pin connector.

Fig. 2 is the three-dimensional combination figure of the utility model socket connector.

Fig. 3 is the part three-dimensional exploded view of the utility model socket connector.

Fig. 4 is the three-dimensional exploded view of the utility model socket connector.

Fig. 5 is the three-dimensional exploded view at another visual angle of the utility model socket connector.

Fig. 6 is the part three-dimensional exploded view of the utility model pin connector.

Fig. 7 is the part three-dimensional exploded view at another visual angle of the utility model pin connector.

Fig. 8 is the three-dimensional exploded view that the utility model pin connector is removed housing.

Fig. 9 is another visual angle three-dimensional exploded view that the utility model pin connector is removed housing.

[embodiment]

See also Fig. 2 to shown in Figure 5, the utility model socket connector 100 comprises jack body 1, be immobilizated in female terminal 3 on the jack body 1, be immobilizated on the jack body 1 in order to optical fiber module 4 that carries out optical signal transmission and the shielding casing 5 that coats jack body 1.

Said jack body 1 comprises first body 10 and is assembled in second body 20 on first body 10.Said first body 10 comprises first base portion 11 and first hyoplastron 12 that extends forward from first base portion 11.First base portion 11 comprises roof 116 on the top, enclose the holding slot 112 that forms at the diapire 117 of bottom, in the two lateral walls 118 of both sides, below being connected dividing plate 115 between the two side 118, being enclosed the accepting groove 110 that forms by roof 116, two side 118 and dividing plate 115 and being positioned at accepting groove 110 by diapire 117, two side 118 and dividing plate 115; Dividing plate 115 separates holding slot 112 and accepting groove 110, and the upper surface of dividing plate 115 is concaved with the support slot 1151 that runs through dividing plate 115 backward.First hyoplastron 12 comprises fluting 120 that the holding slot 112 at the upper surface and first base portion 11 connects, upwards protrudes out the stop blocks 123 in order to stop pin connector 200 excessively to insert at fluting 120 front ends and the some locating slots 121 that are provided with at interval, between two adjacent locating slots 121 with fin 122 that locating slot 121 is separated and from first hyoplastron, 12 upper surface both sides, and said stop block 123 also protrudes out forward from first base portion 11 and forms.Said locating slot 121 runs through the front end face of first hyoplastron 12 forward; The two side 118 of first base portion 11 outwards protrudes out with shielding casing 5 and is provided with the stopper slot 1182 that interlocks and hold with second body 20 in the button of buckle 118 inboards, two side of holding piece 1181, the first base portions 11 mutually.

Said second body 20 comprises second base portions 21 that are assembled in the holding slot 112 and extends forward and be installed on second hyoplastron 22 in the fluting 120 from second base portion 21.Said second base portion, 21 front end faces and rear end face all are concaved with the plurality of fixed groove 211 that vertically extends; The both sides of said second base portion 21 are formed with and said stopper slot 1182 limited block 212 of buckle mutually; Thereby can make said second base portion 21 be fixed on better in the holding slot 112; Said second hyoplastron 22 is contained in the fluting 120 of first hyoplastron 12, and the upper and lower surfaces of second hyoplastron 22 all is concaved with the some grooves 221 that extend along fore-and-aft direction.

The transmission standard of conformance with standard USB 3.0 socket connectors of arranging of female terminal 3, it comprises first female terminal 31 and second female terminal 32.First female terminal 31 comprises first holding parts 311 in the groove 221 that is contained in second hyoplastron, 22 upper surfaces, bend downwards from first holding parts, 311 rear ends to extend and be contained in first weld part 313 in the pickup groove 211 of second base portion, 21 rear ends and bend elasticity first contact site 312, the first weld parts 313 that extension protrudes out second hyoplastron, 22 upper surfaces forward from first holding parts 311 and protrude out second base portion 21 downwards.Second female terminal 32 comprises that second holding parts 321 in the groove 221 that is contained in second hyoplastron, 22 lower surfaces, second weld part 323 from second holding parts, 321 rear ends to the pickup groove 211 that extends below and be contained in second base portion, 21 front end faces in and tabular second contact site 322, the second weld parts 323 that after first holding parts 311 bends extension forward, are contained in the locating slot 121 of first body 10 protrude out second base portion 21 downwards.

Optical fiber module 4 is installed on forward in the accepting groove 110 of jack body 1.Said optical fiber module 4 comprises insulating base 41 and is fixed in the collets 42 of pedestal 41 bottoms in order to positioning optical waveguides (not shown).Said pedestal 41 front end faces each side are provided with a pair of first lens 45; Each is to being provided with a reference column 44 that protrudes out forward between first lens 45; Insulating base 41 bottoms are concaved with in order to the opening 47 of fixed insulation piece 42 and are positioned at two fins 48 of opening 47 both sides, and said reference column 44 is the thick taper shape in the thin rear end of front end, and is formed with square convex tendon 440 on the surface in its outside; First lens 45 can be coupled with fiber optic, light, so that the high-speed optical signal transmission to be provided.Also convex with on the said collets 42 the separated separating part 421 of a pair of optical fiber of correspondence, thereby prevent that optical fiber from touching each other, the support slot 1151 on the dividing plate 115 of fin 48 and jack body 1 matches, and moves forward in order to guide optic fibre module 4 levels.

Shielding casing 5 is coated on jack body 1 outside to reach shield effectiveness.Shielding casing 5 comprises roof 51, the diapire 53 relative with roof 51, be connected the two side 52 of roof 51 and diapire 53 and enclose the receiving space 50 that forms jointly by roof 51, diapire 53 and two side 52.Two side 52 is respectively equipped with the buttons that extend in the receiving space 50 and holds sheet 521 and hold the button that piece 1181 buttons hold with the button of first body 10 and hold hole 522.Said first hyoplastron 12 and the 22 common formation one of second hyoplastron extend into the socket hyoplastron (not label) in the receiving space 50, and first, second contact site 312,322 all is exposed in the receiving space 50.In conjunction with shown in Figure 3, first lens 45 of said optical fiber module 4 are positioned at the rear of first contact site 311 and second contact site 321 and are exposed to receiving space 50, and the reference column 44 of optical fiber module 4 extends first base portion 11 forward and protrudes in the receiving space 50.

Please with reference to shown in Fig. 1 and Fig. 6 to 9; The utility model pin connector 200 can connect with socket connector 100 shown in Figure 2, it comprises header body 6, be retained on some plug terminals 7 on the header body 6, be assembled in fiber device 8 on the header body 6, be retained on stationary installation 9 on the header body 6, coat header body 6 metal shell 201 and metal inner casing 202, be centered around peripheral external insulation layer 203 of metal shell 201 and metal inner casing 202 and the cable 204 that is connected with plug terminal 7 and fiber device 8.

Header body 6 comprises the plug hyoplastron 62 that main part 61 and autonomous body 61 extend forward.Main part 61 is provided with relative two flanks 612 that protrude out and groove 613, two flanks 612 outsides between two flanks 612 downwards and is provided with interlock projection 6121, two flanks 612 inboards of holding of metal shell 201 and is provided with button and holds groove 6122.Plug hyoplastron 62 comprise the fixed fiber device 8 that is positioned at upper surface mounting groove 621, be positioned at mounting groove 621 rears holding tank 620, be positioned at mounting groove 621 the place aheads and a front wide and rear narrow roughly V-shaped stop block 622 that upwards protrudes out, the locating convex block 626 that is positioned at holding tank 620, be positioned at two blind holes 625 of holding tank 620 and the passage 627 that runs through header body 6 and communicate along fore-and-aft direction with mounting groove 621.The lower surface of plug hyoplastron 62 be concaved with one ranked first terminal groove 628 and be positioned at the first terminal groove 628 rears another ranked second terminal groove 629.

The transmission standard of the conformance with standard USB3.0 pin connector of arranging of plug terminal 7, it comprises first plug terminal 71 and second plug terminal 72.First plug terminal 71 comprises first junction surface 711 that is housed in the first terminal groove 628, with first afterbody 713 of cable 204 electric connections and be connected first junction surface 711 and first connecting portion 712 of first afterbody 713.Second plug terminal 72 comprises second junction surface 721 that is housed in second terminal groove 629, with second afterbody 723 of cable 204 electric connections and be connected second junction surface 721 and second connecting portion 722 of second afterbody 723.First junction surface 711 and second junction surface 721 are positioned at the below of plug hyoplastron 62 jointly and form two rows that arrange in front and back, and this first connecting portion 712 is fixed in the main part 61 of header body 6.

Fiber device 8 slidably is housed in to property in the mounting groove 621 of header body 6, and it comprises the insulation slide block 80 that is installed in the mounting groove 621, be installed in optical fiber 81, loam cake 82 on the slide block 80, be clamped in the spring 83 between header body 6 and the fiber device 8 and be installed on the interior cover plate 84 of holding tank 620.Said slide block 80 front end faces each side are provided with a pair of second lens 803; Each is to being provided with a pilot hole 802 between second lens 803; Be provided with stop block 622 between two pilot holes 802 and match and front wide and rear narrow " V " shape depression 801; Pilot hole 802 laterals extend out spread squarely expansion slot 806, and the rear end face of slide block 80 is provided with positioning convex column 804 and is positioned at the breach 805 of positioning convex column 804 both sides.Said second lens 803 carry out optically-coupled with optical fiber 81, thereby the high-speed optical signal transmission is provided.Optical fiber 81 is connected on the slide block 80 through passage 627; Loam cake 82 is fixed in the corresponding breach 805 and then with a pair of optical fiber 81 and is retained on the fiber device 8; The lower surface of loam cake 82 convexes with the optical fiber 81 separated partitions 821 with correspondence, and cover plate 84 bottoms are provided with two projections 842, and cover plate 84 docks with blind hole 625 through projection 842 and accurately is installed in the holding tank 620; One end of spring 83 is socketed on the positioning convex column 804, and the other end is socketed on the locating convex block 626.

Stationary installation 9 comprises locating piece 91 and is installed on the bonnet 92 on the locating piece 91 forward; Locating piece 91 is provided with " T " shape conduit 93 that locating piece 91 is run through in some front and back; Convex with on bonnet 92 front end faces and conduit 93 " T " shape protruding 95 of buckle mutually; Second connecting portion 722 is fixed in the conduit 93, and protruding 95 were pressed on downwards on second connecting portion 722 after bonnet 92 was installed on the locating piece 91, limited second connecting portion 722 and in conduit 93, rocked; The both sides of locating piece 91 rear ends be provided with and detain hold groove 6122 interlock hold support piece 94, locating piece 9 is retained on the header body 6 well.

Metal shell 201 and the metal inner casing 202 common header body 6 that coat are to reach shield effectiveness.Metal shell 201 comprises upper wall 2011, the lower wall 2012 relative with upper wall 2011 and is connected upper wall 2011 and two connecting walls 2013 of lower wall 2012 and the host cavity 2010 that is enclosed to form by upper wall 2011, lower wall 2012 and two connecting walls 2013.All be provided with on said two connecting walls 2013 and the projection 6121 of header body 6 recess 2015 of buckle and the some blocked blocks 2014 that interlock and hold with upper casing 202 mutually; Said plug hyoplastron 62 extends in the host cavity 2010, and said first contact site 711 and second contact site 721 all are exposed in the host cavity 2010.Metal inner casing 202 comprise top 2021 and from the top 2021 to the both sides that extend below 2022, both sides 2022 all are provided with the hole clipping 2023 that the blocked block 2014 with metal shell 201 interlocks and holds.

Please referring to figs. 1 through shown in Figure 9, when pin connector 200 and socket connector 100 connected, second lens 803 of said pin connector 200 alignd to carry out the transmission of light signal with first lens 46 of socket connector 100.Each of the front end face left and right sides of said slide block 80 to be provided with between second lens 803 one from pilot hole 802 that its front end face is arranged with backward with said socket connector 100 on reference column 44 connect; Thereby the reference column 44 that can guide better on the said socket connector 100 inserts; And said pilot hole 802 laterals extend out square expansion slot 806 that spread becomes and match with convex tendon 440 on the said reference column 44; Reach the effect of fool proof; Thereby pilot hole 802 and reference column 44 are located better, guaranteed the center line complete matching of pin connector 200, guarantee the quality of optical signal transmission with socket connector 100.

When pin connector 200 inserts socket connector 100; This fiber device 8 slides in accepting groove 621 backward, after socket connector 100 is extracted, slide block 80 under the acting force of spring 83 to front slide; At this moment; Stop block 622 supports in the depression 801 of slide block 80 front ends, and this stop block 622 of one side is positioned at fiber device 8 front ends and can prevents that fiber device 8 from skidding off accepting groove 621 forward, on the other hand; Can prevent fiber device 8 rocking on left and right directions thereby this stop block 624 matches with depression 801 on the fiber device 8, guarantee that corresponding optical fiber module 4 accurately docks on fiber device 8 and the socket connector 100 on the pin connector 200.

In sum; More than be merely the preferred embodiment of the utility model; Should not limit the scope of the utility model with this; Be that every simple equivalent of being done according to the utility model claims and utility model description changes and modifies, all should still belong in the scope that the utility model patent contains.

Claims

1. socket connector; Be provided with in order to accommodate the receiving space of a pin connector; It comprises jack body, is contained in some female terminals and optical fiber module in the jack body; Said jack body is provided with the socket hyoplastron that extends forwardly in the receiving space; Female terminal comprises that row is located on the socket hyoplastron and is exposed to receiving space with contact site that contacts with pin connector and the weld part that extends jack body; Said optical fiber module comprises and is assembled in the insulating base in the jack body and is located on the pedestal and is exposed to some first lens of receiving space that it is characterized in that: said pedestal also is provided with and extends the reference column that matches in order to pin connector forward, and said reference column is between adjacent two first lens.

2. socket connector as claimed in claim 1; It is characterized in that: said jack body comprises first body and is assembled in second body on first body; Said first body comprises first base portion and first hyoplastron that extends forward from first base portion, and said optical fiber module is assembled on first body.

3. socket connector as claimed in claim 2; It is characterized in that: said first base portion comprises roof on the top, enclose the holding slot that forms at the diapire of bottom, in the two lateral walls of both sides, below being connected dividing plate between the two side, being enclosed the accepting groove that forms by roof, two side and dividing plate and being positioned at accepting groove by diapire, two side and dividing plate; Dividing plate separates holding slot and accepting groove, and said optical fiber module is assembled in forward in the said accepting groove.

4. socket connector as claimed in claim 1; It is characterized in that: the pedestal front end face of said optical fiber module each side is provided with a pair of said first lens; Each is to being provided with a said reference column between first lens; The thin rear end of said reference column front end is thick, is formed with square convex tendon on the surface in the two reference columns outside.

5. socket connector as claimed in claim 3; It is characterized in that: the transmission standard of conformance with standard USB 3.0 socket connectors of arranging of said female terminal; Said female terminal is contained in second body; Second body is assembled in forward in the said holding slot, and said optical fiber module also comprises and carries out the optical fiber of optically-coupled with said first lens and be fixed on the said pedestal to locate the collets of this optical fiber.

6. pin connector; In order to connect with socket connector; It comprises header body, is located at plug terminal and fiber device on the header body; Said header body is provided with extends forward being contained in the plug hyoplastron in the socket connector, and plug terminal is provided with row and is located at the junction surface on the plug hyoplastron, fiber device comprise be assembled on the plug hyoplastron and can before and after the insulation slide block that slides and be located at some second lens on the slide block; It is characterized in that: said slip front face is concaved with the pilot hole that matches in order to socket connector, and said pilot hole is between adjacent two second lens.

7. pin connector as claimed in claim 6; It is characterized in that: the locating convex block that said plug hyoplastron comprises the mounting groove, the holding tank that is positioned at the mounting groove rear that are positioned at the upper surface front end, be positioned at mounting groove the place ahead and a front wide and rear narrow roughly V-shaped stop block that upwards protrudes out and be positioned at holding tank, said slide block is installed in the mounting groove.

8. pin connector as claimed in claim 7 is characterized in that: said slide block also is provided with between two pilot holes and matches with stop block and front wide and rear narrow " V " shape depression, be located at the positioning convex column of rear end face and be positioned at the pilot hole lateral and extend out the square expansion slot that spread becomes.

9. pin connector as claimed in claim 8; It is characterized in that: said fiber device also comprises the spring that is clamped between header body and the fiber device, is fixed in the loam cake of slider bottom in order to fixed fiber; Said spring one end is socketed on the positioning convex column; The other end is socketed on the locating convex block, can in mounting groove, slide front and back at the spring action sliding block.

10. pin connector as claimed in claim 6; It is characterized in that: said pin connector also comprises the stationary installation that is retained on the header body; This stationary installation comprises locating piece and is installed on the bonnet on the locating piece forward; Locating piece is provided with " T " shape conduit that locating piece is run through in some front and back, convexes with on the bonnet front end face that " T " shape of buckle is protruding mutually with said conduit, the transmission standard of conformance with standard USB 3.0 pin connectors of arranging of said plug terminal; Said plug terminal is provided with first junction surface, second junction surface and is fixed on second connecting portion in the conduit; Convexity was pressed on downwards on second connecting portion after said bonnet was installed on the locating piece, limited second connecting portion and in conduit, rocked, and said first junction surface and second junction surface are positioned at the below of plug hyoplastron jointly and form two rows that arrange in front and back.