CN112283225A - a combined bolt - Google Patents

Abstract

Translated fromChinese

一种组合式螺栓，包括独立的螺栓头、螺栓杆、螺栓端，所述螺栓头、螺栓杆、螺栓端可装配固定形成螺栓；所述螺栓头朝向所述螺栓杆的端面上设有凸出的顶块，所述顶块的侧面上设有顶块定位凹槽；所述螺栓杆的外表面设有螺纹，所述螺栓杆中设有轴向设置的第一通孔，所述第一通孔中设有可活动的连接柱，所述连接柱的侧壁上设有第一定位凹槽、第二定位凹槽；所述第一通孔的侧壁上设有可径向伸出的第一定位件和第二定位件。本发明提供了一种全新形式的组合式螺栓，采用模块化结构，可以根据需要装配成需要长度的螺栓进行使用，装配和拆开方便，携带方便。

A combined bolt comprises an independent bolt head, a bolt rod and a bolt end, the bolt head, the bolt rod and the bolt end can be assembled and fixed to form a bolt; the end face of the bolt head facing the bolt rod is provided with a protruding bolt The top block is provided with a top block positioning groove on the side of the top block; the outer surface of the bolt rod is provided with threads, and the bolt rod is provided with an axially arranged first through hole, the first A movable connecting column is arranged in the through hole, a first positioning groove and a second positioning groove are arranged on the side wall of the connecting column; the side wall of the first through hole is provided with a radially extending The first positioning member and the second positioning member. The invention provides a new type of combined bolt, which adopts a modular structure and can be assembled into bolts of required length for use, which is convenient to assemble and disassemble, and convenient to carry.

Description

Combined bolt

Technical Field

The invention belongs to the field of fasteners, and particularly relates to a combined bolt.

Background

The bolt is a mechanical part which is used for fastening and connecting and has wide application, and is widely used in the industries of energy, electronics, electrical appliances, machinery, chemical engineering, metallurgy, dies, hydraulic pressure, home furnishing and the like. The bolt realizes fastening function through screw thread or interference fit when the assembly, and present bolt structure and function are various, all include bolt head and the shank of bolt of shaping on the bolt head generally, and the shank of bolt surface is equipped with the screw thread for rotatory screw assembly.

A bolt, also known as a screw, is a type of fastener that consists of two parts, a head and a shank. Under the general condition, people can come to classify with the screw rod diameter to the same kind of bolt, but in the in-service use process, the bolt of same screw rod diameter often has multiple length specification, in some enterprises of producing multiple different products, non-standard product, because reasons such as product diversity, complexity, even be the bolt of same diameter in the installation, often also can use multi-purpose length specification, because the length specification of bolt is similar, the bolt of same diameter different length all need prepare a bolt box alone and place, not only occupation space, and the user is for saving time, just often can take the neat bolt of required different length once, this bolt that just leads to different length mixes easily.

Therefore, based on the above problems, the present application provides further design and improvement of the bolt structure in the prior art.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the combined bolt, wherein the bolt rod adopts a sectional type combination mode, different lengths can be combined according to actual requirements, different use places can be adapted, the bolt can be stored in three components, and the combined bolt is convenient to classify and carry, assemble and use.

In order to solve the above technical problems, the present invention is solved by the following technical solutions.

A combined bolt comprises a bolt head, a bolt rod and a bolt end which are independent, wherein the bolt head, the bolt rod and the bolt end can be assembled and fixed to form a bolt; a convex top block is arranged on the end face, facing the bolt rod, of the bolt head, and a top block positioning groove is arranged on the side face of the top block; the outer surface of the bolt rod is provided with threads, a first through hole is axially arranged in the bolt rod, a movable connecting column is arranged in the first through hole, and a first positioning groove and a second positioning groove are formed in the side wall of the connecting column; the side wall of the first through hole is provided with a first positioning piece and a second positioning piece which can radially extend out, the first positioning piece can be clamped in the first positioning groove to position the connecting column, the second positioning piece is provided with an upper positioning latch and a lower positioning latch, the side surface of the connecting column facing the positioning latches is provided with at least two second positioning grooves, and the positioning latches can be clamped in the second positioning grooves or separated from the second positioning grooves when the connecting column moves; a second through hole is axially formed in the bolt end, a second positioning piece capable of radially extending out is arranged on the side wall of the second through hole, and an upper positioning latch and a lower positioning latch are arranged on the second positioning piece; the ejector block can be inserted into the first through hole and extrudes the connecting column to move, and one positioning latch on the second positioning piece can be clamped into the ejector block positioning groove to realize assembly; the connecting column can be moved under pressure, and two second positioning grooves on the same side wall of the connecting column are respectively positioned in the two bolt rods and inserted by the corresponding positioning latch, or respectively positioned in one bolt rod and one bolt end and inserted by the corresponding positioning latch.

Bolts in the prior art are of an integral structure for a long time, the length and the diameter of the bolts are determined after production, and the bolts with the matched specifications need to be prepared in an actual use scene, so that workers often need to carry bolts with various different specifications, and the bolts are troublesome.

In this application, changed the integral bolt structure of ever, adopted the bolt of sectional type combination form, in the use, the workman can assemble bolt head, shank of bolt, bolt end together as required and become the bolt of needs and use as required, selects a plurality of shanks of bolt can obtain longer bolt. Therefore, in the application, the bolt head, the bolt rod and the bolt end only need to be carried during working, bolts with different lengths can be assembled on a working site according to needs to be used, and the operation is very convenient.

Combination formula bolt in this application, under the unassembled state, in the first through-hole on the shank of bolt, first positioning piece inserts the first positioning groove on the spliced pole, realizes the location to the spliced pole, and the second positioning groove on the spliced pole all staggers with the location latch this moment, and the second setting element is in the state of withdrawal. In the second through hole on the bolt end, because the connecting column is not arranged, the second positioning piece is in an extending state under the action of elastic force.

When in use, the bolt head and the bolt rod are assembled together: the bolt head and the bolt rod are aligned and extruded, the ejector block on the bolt head is inserted into the first through hole, the ejector block extrudes the connecting column and enables the connecting column to move downwards, at the moment, the first positioning groove on the connecting column is separated from the first positioning piece, and the first positioning piece retracts. In the downward moving process of the ejector block extrusion connecting column, the ejector block positioning groove in the ejector block and one positioning latch in the second positioning piece are mutually buckled and assembled, meanwhile, the other positioning latch in the second positioning piece and one second positioning groove in the connecting column are mutually buckled and assembled, and the process is used for completing the assembly of the bolt head and the bolt rod. At the moment, the lower end of the connecting column extends out of the first through hole, the extending connecting column is equivalent to the function of the ejector block, the bolt can be inserted into the next bolt rod to be assembled, the length of the bolt is increased, or the bolt is inserted into the second through hole in the bolt end, the second positioning groove in the connecting column and the positioning latch on the second positioning piece in the second through hole are mutually buckled and assembled, and the bolt is assembled.

The combination formula bolt in this application also conveniently unpacks apart after the equipment: when the assembled bolt needs to be disassembled, the bolt end or a square cylinder with the same appearance as the connecting column can be inserted into the second through hole from the bottom of the bolt end to extrude the positioning latch on the second positioning piece to retract the second positioning piece, and the bolt end can be separated from the bolt rod.

In a preferred embodiment, the connecting column is a square columnar structure, and the two first positioning grooves are symmetrically arranged and respectively arranged on the opposite side walls of the connecting column; the second positioning grooves are symmetrically arranged in two groups, each group comprises two positioning grooves, and the two positioning grooves are respectively arranged on the opposite side walls of the connecting columns; the position of the first positioning piece corresponds to the position of the first positioning groove, and the position of the second positioning piece corresponds to the position of the second positioning groove.

In a preferred embodiment, a matched inclined plane is arranged between the first positioning groove and the first positioning piece, so that the first positioning piece can be separated from the first positioning groove after being stressed, and the structure is convenient to disassemble.

In a preferred embodiment, a matched inclined plane is arranged between the second positioning groove and the positioning latch, so that the positioning latch can be disengaged from the second positioning groove after being stressed, and the structure is convenient to disassemble.

In a preferred embodiment, the first positioning element is provided with a first spring on the back for providing the elastic force.

In a preferred embodiment, a first through hole on the bolt rod is provided with a first mounting cavity, and a second positioning piece is arranged in the first mounting cavity; a second mounting cavity is arranged in a second through hole in the bolt end, and a second positioning piece is arranged in the second mounting cavity; the back of the second positioning part is provided with a second spring for providing elastic force to enable the second positioning part to move in the first mounting cavity or the second mounting cavity.

In a preferred embodiment, a convex column is arranged on the side of the second positioning piece, a first sliding groove is formed in the first installation cavity, the convex column is arranged in the first sliding groove to slide, the directionality of the second positioning piece during moving is guaranteed, and meanwhile, the outer end of the first sliding groove can be of a sealing structure, so that the second positioning piece is prevented from being separated.

In a preferred embodiment, a convex column is arranged on the side of the second positioning piece, a second sliding groove is formed in the second mounting cavity, the convex column is arranged in the second sliding groove to slide, the directionality of the second positioning piece during moving is guaranteed, and meanwhile, the outer end of the second sliding groove can be of a sealing structure, so that the second positioning piece is prevented from being separated.

In a preferred embodiment, a placing groove for accommodating the first positioning element is formed in a side wall of the first through hole, a first cover plate is covered on the first through hole, a through hole is formed in the first cover plate and is used for the top block or the connecting column to pass through, a protruding block extending downwards is arranged on the side portion of the first cover plate, and the protruding block extends into the placing groove and is used for abutting against the first positioning element.

In a preferred embodiment, a second cover plate is arranged on the second through hole, and a through hole is formed in the second cover plate and used for the top block or the connecting column to pass through.

Compared with the prior art, the invention has the following beneficial effects: the combined bolt has the advantages that the combined bolt is of a brand-new form, the modular structure is adopted, the bolt with the required length can be assembled according to needs to be used, the assembly and the disassembly are convenient, and the carrying is convenient.

Drawings

Fig. 1 is a schematic view showing a separated state of the assembling type bolt according to the present invention.

Fig. 2 is a perspective view of a bolt shank in the present invention.

Fig. 3 is a perspective view of a bolt end in the present invention.

Fig. 4 is an exploded view of the combination bolt of the present invention.

Fig. 5 is a schematic view showing an exploded state of a bolt shank in the present invention.

Fig. 6 is a schematic view showing an exploded state of a bolt end in the present invention.

Fig. 7 is a top view of a bolt shank in the present invention.

Fig. 8 is a schematic sectional view in the direction of a-a in fig. 7.

Fig. 9 is a schematic cross-sectional view taken along the line B-B in fig. 7.

Fig. 10 is a first sectional view of the bolt head according to the present invention.

Fig. 11 is a second sectional view of the bolt head according to the present invention.

Fig. 12 is a top view of the bolt head and bolt shaft of the present invention assembled.

Fig. 13 is a schematic cross-sectional view in the direction C-C in fig. 12.

Fig. 14 is a schematic cross-sectional view in the direction D-D of fig. 12.

Fig. 15 is a perspective view of the bolt head and the bolt shaft of the present invention after assembly.

Fig. 16 is a perspective view of the bolt head, bolt shaft, and bolt end of the present invention after assembly.

Fig. 17 is a first cross-sectional view of the assembled bolt of the present invention.

FIG. 18 is a second cross-sectional view of the assembled bolt of the present invention.

Fig. 19 is a perspective view of a bolt of the present invention assembled with two bolt shanks.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

The embodiments described below by referring to the drawings, in which the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout, are exemplary only for explaining the present invention, and are not construed as limiting the present invention.

In describing the present invention, it is to be understood that the terms: the terms center, longitudinal, lateral, length, width, thickness, up, down, front, back, left, right, vertical, horizontal, top, bottom, inside, outside, clockwise, counterclockwise, and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing and simplifying the description, and thus, should not be construed as limiting the present invention. Furthermore, the terms: first, second, etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features shown. In describing the present invention, unless otherwise expressly specified or limited, the terms: mounting, connecting, etc. should be understood broadly, and those skilled in the art will understand the specific meaning of the terms in this application as they pertain to the particular situation.

Referring to fig. 1 to 19, a combined bolt according to the present application includes abolt head 1, abolt shaft 2, and abolt end 3, where the bolt head 1, thebolt shaft 2, and thebolt end 3 may be assembled and fixed to form a bolt; the specific structure is as follows.

Thebolt head 1 is provided with aconvex top block 13 on the end face facing thebolt rod 2, a topblock positioning groove 131 is arranged on the side face of thetop block 13, and the end face of thebolt head 1, which faces away from thebolt rod 2, is provided with an innerhexagonal groove 11 or an outer hexagonal bulge or other matching structures matched with tools.

The outer surface of thebolt rod 2 is provided with threads, a first throughhole 21 which is axially arranged is formed in thebolt rod 2, a movable connectingcolumn 6 is arranged in the first throughhole 21, and afirst positioning groove 63 and asecond positioning groove 65 are formed in the side wall of the connectingcolumn 6; be equipped withfirst setting element 61 and thesecond setting element 5 that can radially stretch out on the lateral wall of first through-hole 21,first setting element 61 can block and realize the location to splicedpole 6 infirst positioning groove 63, twolocation latch 51 about being equipped with on thesecond setting element 5, be equipped with two at leastsecond positioning groove 65 on the side of splicedpole 6orientation location latch 51, when splicedpole 6 removeslocation latch 51 can block insecond positioning groove 65 or deviate from insecond positioning groove 65.

A second throughhole 31 axially arranged is formed in thebolt end 3, asecond positioning part 5 capable of radially extending is arranged on the side wall of the second throughhole 31, and anupper positioning latch 51 and alower positioning latch 51 are arranged on thesecond positioning part 5; thetop block 13 can be inserted into the first throughhole 21 and press the connectingcolumn 6 to move, and onepositioning latch 51 on thesecond positioning piece 5 can be clamped into the topblock positioning groove 131 to realize assembly; the connectingcolumn 6 can be moved by pressure so that the two second positioning recesses 65 on the same side wall thereof are respectively located in the twobolt shanks 2 and are inserted by thecorresponding positioning latches 51, or respectively located in onebolt shank 2 and onebolt end 3 and are inserted by thecorresponding positioning latches 51.

Specifically, in the present application, the connectingcolumn 6 is a square columnar structure, and the twofirst positioning grooves 63 are symmetrically arranged and respectively arranged on the opposite side walls of the connectingcolumn 6; thesecond positioning grooves 65 are symmetrically arranged in two groups, each group comprises two second positioning grooves, and the two second positioning grooves are respectively arranged on the opposite side walls of the connectingcolumn 6; the position of thefirst positioning element 61 corresponds to the position of thefirst positioning groove 63, and the position of thesecond positioning element 5 corresponds to the position of thesecond positioning groove 65.

In this application,first positioning groove 63 with be equipped with the complex inclined plane between the first locatingpiece 61, make the atress back first locatingpiece 61 can be followed deviate from in thefirst positioning groove 63, this structure is conveniently unpacked apart. Correspondingly, a matched inclined plane is arranged between thesecond positioning groove 65 and thepositioning latch 51, so that thepositioning latch 51 can be separated from thesecond positioning groove 65 after being stressed, and the structure is convenient to disassemble. Thefirst positioning member 61 is provided at the back with afirst spring 62 for providing an elastic force.

In the application, afirst installation cavity 22 is arranged in a first throughhole 21 on thebolt rod 2, and asecond positioning part 5 is arranged in thefirst installation cavity 22; a second mountingcavity 32 is arranged in a second throughhole 31 on thebolt end 3, and asecond positioning piece 5 is arranged in the second mountingcavity 32; the back of thesecond positioning member 5 is provided with asecond spring 52 for providing an elastic force to allow thesecond positioning member 5 to move in the first mountingcavity 22 or the second mountingcavity 32. Furthermore, the side ofsecond setting element 5 is equipped withprojection 53, be equipped withfirst spout 24 in thefirst installation cavity 22,projection 53 is arranged in slide in thefirst spout 24, and directionality when guaranteeingsecond setting element 5 and removing can be for sealing structure, avoidssecond setting element 5 to deviate from simultaneously 24 outer ends of first spout. Correspondingly, the side ofsecond setting element 5 is equipped withprojection 53, be equipped withsecond spout 34 in thesecond installation cavity 32,projection 53 is arranged in slide in thesecond spout 34, and directionality when guaranteeingsecond setting element 5 and removing can be sealing structure forsecond spout 34 outer end simultaneously, avoidssecond setting element 5 to deviate from.

In this application, be equipped with on the lateral wall of first through-hole 21 and be used for holding the standinggroove 23 offirst locating piece 61, be stampedfirst apron 4 on the first through-hole 21, be equipped with through-hole 41 on thefirst apron 4,supply kicking block 13 or splicedpole 6 to pass, the lateral part offirst apron 4 is equipped with thelug 42 that stretches out downwards, lug 42 stretches into and is used for supporting in the standinggroove 23first locating piece 61. And asecond cover plate 48 is arranged on the second throughhole 31, and a through hole is formed in thesecond cover plate 48 and is used for thetop block 13 or the connectingcolumn 6 to pass through.

In this application, changed the integral bolt structure all the time, adopted the bolt of sectional type combination form, in the use, the workman can assemblebolt head 1,bolt pole 2, boltend 3 together as required and become the bolt of needs and use as required, selects a plurality ofbolt poles 2 can obtain longer bolt. Therefore, in the application, thebolt head 1, thebolt rod 2 and thebolt end 3 only need to be carried during working, bolts with different lengths can be assembled on a working site according to needs to be used, and the operation is very convenient.

Combination formula bolt in this application, under the unassembled state, in the first through-hole 21 on the shank ofbolt 2, duringfirst positioning piece 61 inserted thefirst positioning groove 63 on the splicedpole 6, realize the location to splicedpole 6, thesecond positioning groove 65 on the splicedpole 6 this moment all staggers withlocation latch 51, andsecond setting element 5 is in the state of withdrawal. Thesecond positioning member 5 is in an extended state under the elastic force because the connectingcolumn 6 is not provided in the second throughhole 31 of thebolt end 3.

In use, thebolt head 1 and thebolt shaft 2 are assembled together: thebolt head 1 and thebolt rod 2 are aligned and extruded, so that thetop block 13 on thebolt head 1 is inserted into the first throughhole 21, thetop block 13 extrudes the connectingcolumn 6 and enables the connectingcolumn 6 to move downwards, at the moment, thefirst positioning groove 63 on the connectingcolumn 6 is separated from thefirst positioning piece 61, and thefirst positioning piece 61 retracts. In the process that thetop block 13 extrudes the connectingcolumn 6 to move downwards, the topblock positioning groove 131 on thetop block 13 and onepositioning latch 51 on thesecond positioning part 5 are mutually buckled and assembled, meanwhile, theother positioning latch 51 on thesecond positioning part 5 and onesecond positioning groove 65 on the connectingcolumn 6 are mutually buckled and assembled, and the process finishes the assembly of thebolt head 1 and thebolt rod 2. At this time, the lower end of the connectingcolumn 6 extends out of the first throughhole 21, the extended connectingcolumn 6 has a function equivalent to that of thetop block 13, and can be inserted into thenext bolt rod 2 to realize assembly, so that the length of the bolt is increased, or inserted into the second throughhole 31 on thebolt end 3, and thesecond positioning groove 65 on the connectingcolumn 6 and thepositioning latch 51 on thesecond positioning part 5 in the second throughhole 31 are buckled and assembled with each other, thereby completing the assembly of the bolt.

The combination formula bolt in this application also conveniently unpacks apart after the equipment: for the assembled bolt, when the assembled bolt needs to be disassembled, the connectingcolumn 6 or the square cylinder with the same shape as the connectingcolumn 6 can be inserted into the second throughhole 31 from the bottom of thebolt end 3, thepositioning latch 51 on thesecond positioning piece 5 in the connecting column is extruded, thesecond positioning piece 5 retracts, thebolt end 3 can be separated from thebolt rod 2 at the moment, then thesecond positioning piece 5 protruding out of thebolt rod 2 is extruded, thesecond positioning piece 5 in thebolt rod 2 can retract, thebolt rod 2 can be separated from thebolt rod 2 or thebolt head 1, and the operation is convenient.

The invention provides a novel combined bolt, which adopts a modular structure, can be assembled into a bolt with required length for use according to requirements, and is convenient to assemble and disassemble and convenient to carry.

The scope of the present invention includes, but is not limited to, the above embodiments, and the present invention is defined by the appended claims, and any alterations, modifications, and improvements that may occur to those skilled in the art are all within the scope of the present invention.

Claims (10)

1. The combined bolt is characterized by comprising an independent bolt head (1), a bolt rod (2) and a bolt end (3), wherein the bolt head (1), the bolt rod (2) and the bolt end (3) can be assembled and fixed to form a bolt;

a convex top block (13) is arranged on the end face, facing the bolt rod (2), of the bolt head (1), and a top block positioning groove (131) is arranged on the side face of the top block (13);

the outer surface of the bolt rod (2) is provided with threads, a first through hole (21) which is axially arranged is formed in the bolt rod (2), a movable connecting column (6) is arranged in the first through hole (21), and a first positioning groove (63) and a second positioning groove (65) are formed in the side wall of the connecting column (6); the side wall of the first through hole (21) is provided with a first positioning piece (61) and a second positioning piece (5) which can radially extend out, the first positioning piece (61) can be clamped in a first positioning groove (63) to position the connecting column (6), the second positioning piece (5) is provided with an upper positioning latch and a lower positioning latch (51), the side surface of the connecting column (6) facing the positioning latches (51) is provided with at least two second positioning grooves (65), and the positioning latches (51) can be clamped in the second positioning grooves (65) or can be separated from the second positioning grooves (65) when the connecting column (6) moves;

a second through hole (31) axially arranged is formed in the bolt end (3), a second positioning piece (5) capable of radially extending is arranged on the side wall of the second through hole (31), and an upper positioning latch and a lower positioning latch (51) are arranged on the second positioning piece (5);

the top block (13) can be inserted into the first through hole (21) and extrudes the connecting column (6) to move, and one positioning latch (51) on the second positioning piece (5) can be clamped into the top block positioning groove (131) to realize assembly;

the connecting column (6) can be moved under pressure, and two second positioning grooves (65) on the same side wall of the connecting column are respectively positioned in two bolt rods (2) and inserted by corresponding positioning latch teeth (51), or respectively positioned in one bolt rod (2) and one bolt end (3) and inserted by corresponding positioning latch teeth (51).

2. The combined bolt according to claim 1, wherein the connecting column (6) is a square column structure, and the two first positioning grooves (63) are symmetrically arranged and respectively arranged on the opposite side walls of the connecting column (6); the second positioning grooves (65) are symmetrically arranged in two groups, and each group comprises two positioning grooves, and the two positioning grooves are respectively arranged on the opposite side walls of the connecting column (6); the position of the first positioning piece (61) corresponds to the position of the first positioning groove (63), and the position of the second positioning piece (5) corresponds to the position of the second positioning groove (65).

3. A combined bolt according to claim 1, characterised in that a cooperating ramp is provided between the first location recess (63) and the first locating member (61) to enable the first locating member (61) to be removed from the first location recess (63) when subjected to a force.

4. A combined bolt according to claim 1, characterised in that a cooperating ramp is provided between the second detent recess (65) and the detent (51) to enable the detent (51) to be disengaged from the second detent recess (65) when subjected to a force.

5. A modular bolt according to claim 1, characterised in that the first locating member (61) is backed by a first spring (62).

6. A combined bolt according to claim 1, characterised in that the first through hole (21) in the bolt shank (2) is provided with a first mounting cavity (22), and the first mounting cavity (22) is provided with a second locating member (5); a second mounting cavity (32) is formed in a second through hole (31) in the bolt end (3), and a second positioning piece (5) is arranged in the second mounting cavity (32); the back of the second positioning piece (5) is provided with a second spring (52).

7. A combined bolt according to claim 6, characterised in that the second location member (5) is provided with a protruding post (53) at a side thereof, the first mounting cavity (22) is provided with a first sliding slot (24), and the protruding post (53) is slidably disposed in the first sliding slot (24).

8. A combined bolt according to claim 6, characterised in that the second locating element (5) is provided with a protruding post (53) on its side, the second mounting cavity (32) is provided with a second sliding slot (34), and the protruding post (53) is slidably disposed in the second sliding slot (34).

9. A combined bolt according to claim 1, characterised in that the side wall of the first through hole (21) is provided with a placement groove (23) for accommodating the first positioning element (61), the first through hole (21) is covered with a first cover plate (4), the first cover plate (4) is provided with a through hole (41), the side of the first cover plate (4) is provided with a downwardly extending projection (42), and the projection (42) extends into the placement groove (23) for abutting against the first positioning element (61).

10. A combined bolt according to claim 1, characterised in that a second cover plate (48) is provided over the second through hole (31), the second cover plate (48) being provided with a through hole.

Images