CN217158798U

CN217158798U - Connecting device

Info

Publication number: CN217158798U
Application number: CN202220444532.4U
Authority: CN
Inventors: 朱光明; 向波
Original assignee: Zhongshan Lingke Electric Co ltd
Current assignee: Zhongshan Lingke Electric Co ltd
Priority date: 2022-03-01
Filing date: 2022-03-01
Publication date: 2022-08-09
Anticipated expiration: 2032-03-01

Abstract

The utility model discloses a connecting device, include: a connection device, comprising: a first joint; a second joint; the connecting piece is rotatably arranged on the second joint and can move relative to the second joint; the first connector is provided with a clamping position, the connecting piece is provided with at least one locking part, the locking part is clamped and matched with the clamping position, and when the first connector and the second connector are spliced, the connecting piece rotates relative to the second connector so that the locking part is clamped in the clamping position; at least one clamping position is provided with a stopping structure, and the stopping structure is used for being matched with the locking part to limit the locking part to be separated from the clamping position. The relative second of connecting piece connects rotates and removes for locking portion can pass through the stopping structure and be located the joint position, thereby accomplishes connecting device's quick installation and targets in place, and prevents that first joint and second joint from loosening relatively in the use, and simple structure, the installation is all very convenient with the dismantlement, low in manufacturing cost, and assembly efficiency is high, has improved connecting device's stability and leakproofness.

Description

Connecting device

Technical Field

The utility model relates to an electric connecting device technical field, in particular to connecting device.

Background

The existing connecting device comprises a male connector, a female connector and a nut for connecting the male connector and the female connector, wherein the nut is arranged on the female connector, and the male connector and the female connector are connected in an inserting mode and then are connected with the male connector through the nut in a rotating and screwing mode. However, the connection method of screwing the nut to connect the male connector and the female connector is not only difficult to assemble, but also reduces the sealing performance between the male connector and the female connector due to the defect that the nut is not easy to screw in place; in addition, along with the increase of the service time of the connecting device, the loosening phenomenon easily occurs between the male connector and the nut due to vibration, so that the male connector and the female connector are relatively loosened to be separated, and the stability is poor.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides a connecting device, connecting device assembles conveniently, and is difficult for appearing the pine phenomenon of taking off.

According to the utility model discloses connecting device, include: a first joint; the second connector is in plug-in fit with the first connector; the connecting piece is rotatably arranged on the second joint and can move relative to the second joint; one of the first connector and the connecting piece is provided with at least one clamping position, the other one of the first connector and the connecting piece is provided with at least one locking part, the locking part is in clamping fit with the clamping position, and when the first connector and the second connector are spliced, the connecting piece rotates relative to the second connector so that the locking part is clamped in the clamping position; at least one be provided with the stopping structure on the joint position, the stopping structure be used for with locking portion cooperation is in order to restrict locking portion breaks away from the joint position.

According to the utility model discloses connecting device has following beneficial effect at least: adopt above-mentioned structure, when first joint and second connect and peg graft the back and lock through the connecting piece, the relative second of connecting piece connects and rotates and remove, make locking portion can be through stopping the structure and lie in the joint position, the connecting piece can't rotate relative second joint, thereby accomplish connecting device's quick installation targets in place, and prevent in the use that first joint and second connect relative pine to take off, moreover, the steam generator is simple in structure, it is all very convenient to install and dismantle, low in manufacturing cost, high in assembly efficiency, connecting device's stability and leakproofness have been improved.

According to some embodiments of the utility model, the joint position including the guiding groove and with the joint groove of guiding groove intercommunication, the stopping structure be for set up in the bellying of joint inslot, the bellying is located the joint groove is kept away from the one end of guiding groove, the bellying be used for with the locking portion butt.

According to some embodiments of the invention, the first joint comprises a plug end, the clamping location is arranged on an outer wall of the plug end; the connecting piece is a cylindrical structure which is rotatably sleeved on the second joint, an inserting groove for inserting the inserting end is formed between the outer wall of the second joint and the inner wall of the connecting piece, and the locking part is arranged on the inner wall of the connecting piece.

According to some embodiments of the utility model, the grafting end is provided with the recess, the recess is used for installing first contact pin, the second connects including being located the projection of inserting groove, the projection be used for the installation with the second contact pin that first contact pin electricity is connected, first contact pin with when the second contact pin electricity is connected the at least partial region of projection is located in the recess.

According to some embodiments of the present invention, the projection is provided with a sealing structure for sealing a gap between an upper sidewall of the projection and an upper opposing sidewall of the groove.

According to some embodiments of the utility model, be provided with the guide way on the outer wall of projection, the end of pegging graft be provided with be located the recess and with guide way joint complex direction arch.

According to some embodiments of the present invention, the second pin is connected to a cable, and a tail sleeve connected to the second pin and sleeved on the cable is disposed on one side of the second joint; and a limiting sliding groove in sliding fit with the connecting piece is arranged between the tail sleeve and the second joint, and the limiting sliding groove is used for limiting the moving stroke of the connecting piece relative to the second joint.

According to some embodiments of the utility model, the outer wall that the second connects is provided with annular boss, annular boss the tail cover and the second connects encloses to close and forms spacing spout, the one end of connecting piece is provided with radial convex lug inwards, lug slidable ground card is located spacing spout.

According to some embodiments of the present invention, the first joint further comprises a positioning boss and an installation end sequentially arranged along an axial direction thereof, one side of the positioning boss is connected to the insertion end, and the other side of the positioning boss is connected to the installation end; the mounting end is detachably connected with a fixing piece, and a clamping space is arranged between the fixing piece and the positioning boss.

According to some embodiments of the invention, the mounting end comprises a fixed section connected with the positioning boss and a threaded section connected with the fixed section; the fixing piece is a nut in threaded connection with the threaded section.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural diagram of a connecting device according to an embodiment of the present invention;

fig. 2 is a first schematic cross-sectional view of a connection device according to an embodiment of the invention;

FIG. 3 is an enlarged schematic view of the structure at A in FIG. 2;

fig. 4 is a second schematic cross-sectional view of a connection device according to an embodiment of the present invention;

FIG. 5 is an enlarged schematic view of the structure at B in FIG. 4;

fig. 6 is a first exploded schematic view of a connecting device according to an embodiment of the present invention;

fig. 7 is a second exploded schematic view of the connecting device according to the embodiment of the present invention;

FIG. 8 is a cross-sectional view of the alternative view of FIG. 7;

reference numerals:

the connector comprises a first connector 10, an inserting end 11, a groove 12, a guide protrusion 13, a positioning boss 14, a mounting end 15, a fixing section 151 and a threaded section 152;

the second joint 20, the convex column 21, the annular groove 211 and the guide groove 212;

the annular boss 22, the connecting piece 30 and the lug 31;

a clamping position 41, a guide groove 411, a clamping groove 412 and a locking part 42;

a backstop structure 50, an insertion groove 60;

cable 71, tail cover 72, spacing spout 73.

Detailed Description

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

In the description of the present invention, it should be understood that the orientation or positional relationship indicated with respect to the orientation description, such as up, down, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, if there are first and second descriptions for distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the precedence of the indicated technical features.

In the description of the present invention, unless there is an explicit limitation, the words such as setting, installation, connection, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in combination with the specific contents of the technical solution.

As shown in fig. 1 to 8, the connecting device according to the embodiment of the present invention includes: a first joint 10; the second connector 20 is in inserted fit with the first connector 10; the connecting piece 30 is rotatably arranged on the second joint 20, and the connecting piece 30 can move relative to the second joint 20; the first connector 10 is provided with at least one clamping position 41, the connecting piece 30 is provided with at least one locking part 42, the locking part 42 is in clamping fit with the clamping position 41, and when the first connector 10 and the second connector 20 are spliced, the connecting piece 30 rotates relative to the second connector 20 so that the locking part 42 is clamped in the clamping position 41; at least one clamping position 41 is provided with a retaining structure 50, and the retaining structure 50 is used for being matched with the locking part 42 to limit the locking part 42 to be separated from the clamping position 41.

Of course, in some embodiments, the first connector 10 may also be provided with the locking portion 42, and the connecting member 30 is provided with the snap-in location 41, which still has the above-mentioned effects.

It will be appreciated that in some embodiments of the invention, the first connector 10 is a male connector and the second connector 20 is a female connector. Of course, in some embodiments, or vice versa, the first connector 10 may be a female connector and the second connector 20 may be a male connector.

It should be noted that, in some embodiments of the present invention, the clamping sites 41 with the retaining structures 50 are arranged alternately with two other clamping sites 41 without retaining structures 50; in some embodiments, the number of the clamping units 41 and the locking portions 42 can also be set to be one, or two, three, etc., and is not limited herein.

According to the utility model discloses connecting device, adopt above-mentioned structure, when first joint 10 and second connect 20 to peg graft the back and lock through connecting piece 30, connecting piece 30 second joint 20 rotates and removes relatively, make locking portion 42 can pass through stopping structure 50 and lie in joint position 41, connecting piece 30 can not rotate second joint 20 relatively, thereby accomplish connecting device's quick installation and target in place, and prevent that first joint 10 and second joint 20 from taking off relatively in the use, moreover, the steam generator is simple in structure, it is all very convenient to install and dismantle, therefore, the low manufacturing cost, the assembly efficiency is high, connecting device's stability and leakproofness have been improved.

It can be understood that, as shown in fig. 1 to 8, in some embodiments of the present invention, the clamping position 41 includes a guiding groove 411 and a clamping groove 412 communicated with the guiding groove 411, the retaining structure 50 is a protrusion portion disposed in the clamping groove 412, the protrusion portion is located at one end of the clamping groove 412 far away from the guiding groove 411, and the protrusion portion is used for abutting against the locking portion 42. Adopt above-mentioned structure, when first joint 10 and second joint 20 cartridge are connected, connect the relative second of connecting piece 30 and connect 20 and rotate, thereby push into locking portion 42 to joint groove 412 along guiding groove 411, through bellying butt in locking portion 42 one side, and then accomplish the locking connection of first joint 10 and second joint 20, the installation is all very convenient with the dismantlement, low in manufacturing cost, high assembly efficiency, and play the guide effect through the guiding groove 411 to the joint cooperation of locking portion 42 and joint groove 412, high durability and convenient operation, and is labor-saving.

As shown in fig. 2, 3, 6 and 7, in some embodiments of the present invention, two ends of the protruding portion along the axial direction of the first joint 10 are respectively connected to two opposite sidewalls of the engaging groove 412; of course, in some embodiments, the protrusion may also be configured to have one end connected to one sidewall of the engaging groove 412 and the other end spaced from the other sidewall of the engaging groove 412, so that the locking portion 42 can move along the guiding groove 411 and enter the engaging groove 412 with a gap.

It should be noted that, in the embodiment of the present invention, the first joint 10, the second joint 20 and the connecting member 30 are made of plastic material, so when the locking portion 42 enters the clamping groove 412 through the protruding portion, the connecting member 30 has a certain elastic deformation to make the locking portion 42 cross over the protruding portion and be clamped in the clamping groove 412, so as to complete the locking.

It is contemplated that, as shown in fig. 1-8, in some embodiments of the present invention, the first connector 10 includes a plug end 11, and the latch site 41 is disposed on an outer wall of the plug end 11; the connecting member 30 is a cylindrical structure rotatably sleeved on the second joint 20, an insertion groove 60 for the insertion of the insertion end 11 is formed between the outer wall of the second joint 20 and the inner wall of the connecting member 30, and the locking portion 42 is disposed on the inner wall of the connecting member 30. Adopt above-mentioned structure, first joint 10 and second joint 20 peg graft through grafting end 11 and inserting groove 60, connecting piece 30 rotates relative second joint 20, so that locking portion 42 pushes in to joint groove 412 along guiding groove 411, through the bellying butt in locking portion 42 one side, and then accomplish the locking connection of first joint 10 and second joint 20, and inserting groove 60 can cladding joint position 41 and locking portion 42's joint cooperation department, certain guard action has been played, the stability and the leakproofness of connector have been improved.

It should be noted that, in some embodiments of the present invention, four locking slots are circumferentially spaced along the outer wall of the insertion end 11; the outer wall of the connecting member 30 is provided with anti-slip ribs so that the user can drive the connecting member 30 to rotate.

It can be understood that, as shown in fig. 1 to 8, in some embodiments of the present invention, the guiding groove 411 includes a first guiding wall and a second guiding wall abutting against two opposite side walls of the engaging groove 412 respectively along the axial direction of the inserting end 11 on the engaging groove 412, the first guiding wall and the second guiding wall are both inclined from the two opposite side walls of the engaging groove 412, and the first guiding wall and the second guiding wall are spaced to form a gap for the locking portion 42 to move to engage in the engaging groove 412, wherein the length of the first guiding wall is greater than that of the second guiding wall, and the first guiding wall includes a first inclined edge and a second inclined edge having one end connected with the first inclined edge, the first inclined edge extends to the gap of the guiding groove 411, the other end of the second inclined edge is connected with one side wall of the engaging groove 412, the width of the gap of the guiding groove 411 is smaller than that of the engaging groove 412, locking portion 42 stretches into in the guiding groove 411 and removes along guiding groove 411 through the breach, through rotating connecting piece 30 for locking portion 42 rotates and removes and crosses the country bellying towards joint groove 412, locking portion 42 and the cooperation of joint groove 412 joint, and bellying to butt in locking portion 42, thereby drive first joint 10 and second joint 20 and be close to in opposite directions and locking connection.

It will be appreciated that in some embodiments of the present invention, as shown in fig. 2, 4, 6-8, the insertion end 11 is provided with a groove 12, the groove 12 is used for mounting a first pin, the second connector 20 includes a protrusion 21 located in the insertion groove 60, the protrusion 21 is used for mounting a second pin electrically connected to the first pin, and at least a partial region of the protrusion 21 is located in the groove 12 when the first pin is electrically connected to the second pin. During installation, the first inserting pin is installed in the groove 12, the convex column 21 is inserted into the groove 12, the groove 12 covers the convex column 21, and the inserting groove 60 covers the inserting end 11, so that the sealing performance is improved, and a certain waterproof effect is achieved. It should be noted that the convex pillar 21 covers the second pin.

As shown in fig. 2, 4, 6 to 8, in some embodiments of the present invention, a sealing structure is disposed on the protruding column 21, and the sealing structure is used for sealing a gap between an upper side wall of the protruding column 21 and an opposite side wall of the groove 12, so as to improve the waterproof performance.

It can be understood that, as shown in fig. 2, 4, 6 to 8, in some embodiments of the present invention, the sealing structure includes two annular grooves 211 and two sealing rings, the sealing rings and the annular grooves 211 are disposed in a one-to-one correspondence, the two annular grooves 211 are sequentially disposed along the axial direction of the protruding pillar 21, and one of the annular grooves 211 is located at an end portion of the protruding pillar 21 close to the inserting end 11. When in plugging, the sealing ring in the annular groove 211 at the end part close to the plugging end 11 on the convex column 21 is abutted to the end part of the plugging end 11, and the sealing ring of the other annular groove 211 is positioned between the convex column 21 and the groove 12.

Of course, in some embodiments, the number of the annular grooves 211 and the sealing rings may also be set to one, three, etc., and is not limited herein.

In some embodiments of the present invention, the outer wall of the protruding column 21 is provided with a guiding groove 212, and the inserting end 11 is provided with a guiding protrusion 13 located in the groove 12 and engaged with the guiding groove 212. The first connector 10 and the second connector 20 are guided when being plugged.

It can be understood that, as shown in fig. 1, fig. 2, fig. 4 and fig. 6 to fig. 8, in some embodiments of the present invention, the second pin is connected to the cable 71, and one side of the second connector 20 is provided with a tail sleeve 72 connected thereto and sleeved on the cable 71; a limiting sliding groove 73 in sliding fit with the connecting piece 30 is arranged between the tail sleeve 72 and the second joint 20, and the limiting sliding groove 73 is used for limiting the moving stroke of the connecting piece 30 relative to the second joint 20. By adopting the structure, when the first connector 10 and the second connector 20 are spliced, namely the splicing end 11 is inserted into the splicing groove 60, the connecting piece 30 is driven to move towards the splicing end 11 of the first connector 10 by rotating relative to the second connector 20 through the connecting piece 30, so that the first connector 10 and the second connector 20 approach to each other and are matched with the protruding part through the locking part 42, and the locking part 42 is clamped in the clamping groove 412 for locking connection; when the first connector 10 and the second connector 20 need to be separated, the connecting piece 30 rotates reversely relative to the second connector 20 and moves back to the first connector 10, and the locking part 42 is matched with the protruding part and moves away from the inserting end 11 of the first connector 10 through the guide groove 411, so that the separation is completed, the structure is simple, the limiting is reliable, the connecting piece 30 is prevented from being separated from the second connector 20 due to excessive movement, and the normal connection of the connecting device is ensured.

As shown in fig. 1, fig. 2, fig. 4 and fig. 6 to fig. 8, in some embodiments of the present invention, the outer wall of the second joint 20 is provided with an annular boss 22, the tail sleeve 72 and the second joint 20 enclose to form a limiting sliding groove 73, one end of the connecting member 30 is provided with a radially inward protruding bump 31, and the bump 31 is slidably clamped in the limiting sliding groove 73. With the above structure, the annular boss 22 abuts against one side wall of the projection 31 of the connecting member 30 toward the insertion groove 60 to limit the maximum moving distance of the connecting member 30 toward the insertion end 11; the lug 31 abutting against the connecting piece 30 abuts against one side wall of the tail sleeve 72 to limit the maximum moving distance of the connecting back to the plugging end 11, the structure is simple, the movement is stable and reliable, and the connecting piece 30 is more compactly and reliably installed on the second connector 20.

As shown in fig. 1, 2, 4, and 6 to 8, in some embodiments of the present invention, the first joint 10 further includes a positioning boss 14 and a mounting end 15 sequentially arranged along an axial direction thereof, one side of the positioning boss 14 is connected to the insertion end 11, and the other side of the positioning boss 14 is connected to the mounting end 15; wherein, the mounting end 15 is detachably connected with a fixing piece, and a clamping space is arranged between the fixing piece and the positioning boss 14. With the above structure, the connecting device is assembled to an object (e.g. a lamp) to be electrically connected, taking the lamp as an example: during installation, the installation end 15 is inserted into the shell of the lamp, the fixing piece abuts against the inner wall of the shell of the lamp, the annular boss 22 abuts against the outer wall of the shell, the shell is clamped in the clamping space, and the connecting device is fixedly installed on the lamp through the fixing piece.

As shown in fig. 1, 2 and 4-6, in some embodiments of the present invention, the mounting end 15 includes a fixed section 151 connected to the positioning boss 14 and a threaded section 152 connected to the fixed section 151; the fixing member is a nut screwed with the threaded section 152, and the nut can move along the threaded section 152 to an end of the threaded section 152 close to the fixing section 151, so that a side surface of the nut is matched with a side surface of the positioning boss 14, and the fixing section 151 is matched to form a clamping space. By adopting the structure, the nut is screwed up in a rotating way relative to the thread section 152, so that objects needing to be electrically connected are clamped in the clamping space, the structure is simple, and the installation and the disassembly are convenient.

It should be noted that, as shown in fig. 1, fig. 2, fig. 4 and fig. 6 to fig. 8, in some embodiments of the present invention, since the first connector 10, the second connector 20, the connecting member 30 and the tail sleeve 72 are made of plastic material, after the second pin and the second connector 20 are injection molded, the connecting member 30 is sleeved on the second connector 20, and then the tail sleeve 72 and the second connector 20 are injection molded; of course, in some embodiments, the first pin may also be injection molded with the first connector 10.

It is understood that, in some embodiments of the present invention, the tail sleeve 72 is bent, but the tail sleeve 72 may also be configured to be a straight shape, which is not limited herein.

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

The invention is not limited to the above embodiments, and those skilled in the art can make equivalent modifications or substitutions without departing from the spirit of the invention, and such equivalent modifications or substitutions are included in the scope defined by the claims of the present application.

Claims

1. A connection device, comprising:

a first joint (10);

the second connector (20) is in plug fit with the first connector (10);

the connecting piece (30) is rotatably arranged on the second joint (20), and the connecting piece (30) can move relative to the second joint (20);

one of the first connector (10) and the connecting piece (30) is provided with at least one clamping position (41), the other one of the first connector and the connecting piece is provided with at least one locking part (42), the locking part (42) is in clamping fit with the clamping position (41), and when the first connector (10) and the second connector (20) are plugged, the connecting piece (30) rotates relative to the second connector (20) so that the locking part (42) is clamped in the clamping position (41);

at least one be provided with stopping structure (50) on joint position (41), stopping structure (50) be used for with locking portion (42) cooperation is in order to restrict locking portion (42) break away from joint position (41).

2. The connecting device according to claim 1, wherein the clamping position (41) comprises a guide groove (411) and a clamping groove (412) communicated with the guide groove (411), the retaining structure (50) is a protruding portion arranged in the clamping groove (412), the protruding portion is located at one end, away from the guide groove (411), of the clamping groove (412), and the protruding portion is used for being abutted to the locking portion (42).

3. The connecting device according to claim 2, characterized in that the first connector (10) comprises a plug end (11), the clamping position (41) being arranged on an outer wall of the plug end (11);

the connecting piece (30) is rotatably sleeved on the tubular structure of the second connector (20), an inserting groove (60) for inserting the inserting end (11) is formed between the outer wall of the second connector (20) and the inner wall of the connecting piece (30), and the locking part (42) is arranged on the inner wall of the connecting piece (30).

4. A connection device according to claim 3, characterized in that the plug end (11) is provided with a recess (12), which recess (12) is intended for mounting a first pin,

the second connector (20) comprises a convex column (21) positioned in the insertion groove (60), the convex column (21) is used for installing a second contact pin electrically connected with the first contact pin, and at least part of area of the convex column (21) is positioned in the groove (12) when the first contact pin is electrically connected with the second contact pin.

5. A connection device according to claim 4, characterized in that the stud (21) is provided with sealing means for sealing a gap between an upper side wall of the stud (21) and an opposite side wall of the recess (12).

6. A connecting device according to claim 4 or 5, characterized in that the outer wall of the protruding column (21) is provided with a guide groove (212), and the inserting end (11) is provided with a guide projection (13) which is positioned in the groove (12) and is in clamping fit with the guide groove (212).

7. The connecting device according to claim 4, characterized in that the second pin is connected with a cable (71), and one side of the second connector (20) is provided with a tail sleeve (72) connected with the second pin and sleeved on the cable (71);

a limiting sliding groove (73) in sliding fit with the connecting piece (30) is arranged between the tail sleeve (72) and the second joint (20), and the limiting sliding groove (73) is used for limiting the moving stroke of the connecting piece (30) relative to the second joint (20).

8. The connecting device according to claim 7, characterized in that an annular boss (22) is arranged on the outer wall of the second joint (20), the annular boss (22), the tail sleeve (72) and the second joint (20) enclose to form the limiting sliding groove (73), a projection (31) which protrudes radially inwards is arranged at one end of the connecting piece (30), and the projection (31) is slidably clamped in the limiting sliding groove (73).

9. The connecting device according to claim 8, wherein the first joint (10) further comprises a positioning boss (14) and a mounting end (15) which are sequentially arranged along the axial direction of the first joint, one side of the positioning boss (14) is connected with the inserting end (11), and the other side of the positioning boss (14) is connected with the mounting end (15);

the mounting end (15) is detachably connected with a fixing piece, and a clamping space is arranged between the fixing piece and the positioning boss (14).

10. The connecting device according to claim 9, wherein the mounting end (15) comprises a fixing section (151) connected with the positioning boss (14) and a threaded section (152) connected with the fixing section (151);

the fixing piece is a nut screwed with the threaded section (152).