Combined bolt assembly and mounting and using method thereof

Abstract

The invention discloses a combined bolt assembly and a mounting and using method thereof, and relates to the technical field of bolt connectors, the combined bolt assembly comprises a first nut, the outer surface of the lower end of the first nut is fixedly connected with a first threaded column, and the outer surface of the lower end of the first threaded column is movably connected with a second threaded column; a through hole is formed in the outer surface of the upper end of the first nut, the outer surface of the upper end of the first nut is connected with a fixing column in an inserted mode, a second nut is fixedly connected to the outer surface of the upper end of the fixing column, a first limiting rod is fixedly connected to the outer surface of the lower end of the fixing column, and a first fixing block is fixedly connected to the outer circle face of the second nut. After the bolt assembly is used, slipping after the bolt is touched is avoided, falling of the bolt is avoided, the bolt assembly is fixed, when the bolt assembly needs to be taken down, a wrench with the same size as a nut on the bolt assembly does not need to be found to disassemble the bolt assembly, a plurality of wrenches of different models do not need to be carried, and therefore use is convenient.

Description

Technical Field

[0001] The present invention relates to the technical field of bolt connectors, and in particular to a combined bolt assembly and an installation and use method thereof. Background Art

[0002] In recent years, with the rapid development of my country's economy, people's living standards have gradually improved, and the toy industry has developed rapidly and diversified. As a kind of intellectual and hands-on toys, assembly toys are especially popular among teenagers, children and parents. The general assembly method of assembly toys is to lock the parts with bolts to form a whole, but in this way, a toy needs to be equipped with a lot of bolts, and some toys even need to be equipped with about 40 bolts.

[0003] After searching, the Chinese patent number CN103133478A discloses a combined bolt assembly and its installation and use method, including a bolt and a nut, the bolt includes a head and a screw rod extending downward from the bottom surface of the head, the screw rod includes a bare rod section extending downward from the head, and a threaded section extending downward from the bare rod section and having a length shorter than the bare rod section, the bottom surface of the head has one or more first magnetic objects, the first magnetic objects are arranged around the screw rod, the nut includes one or more second magnetic objects with opposite polarity to the first magnetic objects, and the inner surface of the nut is provided with an internal thread that matches the threaded section and whose inner diameter is not less than the diameter of the bare rod section.

[0004] Compared with the prior art, the practical invention patent with Chinese patent number CN103133478A can make the connection quick and not easy to separate, and at the same time, due to the existence of the threaded section, it can ensure that the nut is not easy to be lost.

[0005] However, in actual use, the above device is prone to slipping after hitting the bolt, which may cause the bolt to fall off. It is inconvenient to fix it again after slipping. The bolt falling off may cause an impact and it is inconvenient to fix it. When the bolt assembly needs to be removed, a wrench of the same size as the nut on the bolt assembly is needed to disassemble the bolt assembly. It is necessary to carry multiple wrenches of different models, which increases the weight of the carry-on. It is inconvenient to disassemble it without a wrench of the same model, which affects the use. Summary of the invention

[0006] The purpose of the present invention is to solve the problem in the prior art that the bolt may slip after being touched by the bolt after use, which may cause the bolt to fall off, and it is inconvenient to fix it again after slipping. The bolt may cause an impact after falling off, and it is inconvenient to fix it. When the bolt assembly needs to be removed, it is necessary to find a wrench of the same size as the nut on the bolt assembly to disassemble the bolt assembly. It is necessary to carry multiple wrenches of different models, which increases the carrying weight. It is inconvenient to disassemble it without a wrench of the same model, which affects the use. A combined bolt assembly and its installation and use method are proposed.

[0007] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a combined bolt assembly, the above-mentioned technical scheme further includes a first nut, a first threaded column is fixedly connected to the outer surface of the lower end of the first nut, a second threaded column is movably connected to the outer surface of the lower end of the first threaded column, a through hole is opened on the outer surface of the upper end of the first nut, the outer surface of the upper end of the first nut is plugged and connected with the fixing column, the outer surface of the upper end of the fixing column is fixedly connected to the second nut, the outer surface of the lower end of the fixing column is fixedly connected to the first limiting rod, the outer circular surface of the second nut is fixedly connected to the first fixing block, the outer surface of the rear end of the first fixing block is fixedly installed with a rotating block, and the rotating block The outer surface of the rear end of the moving block is rotatably connected to a rotating column, the outer circular surface of the rotating column is fixedly connected to a fixing plate, the outer surface of the left side of the fixing plate is fixedly connected to a second limiting rod, the outer surface of the left side of the second fixing block is provided with a sliding groove, the outer surface of the upper end of the first nut is fixedly connected to the second fixing block, the outer surface of the front end of the second limiting rod is provided with a first cavity, the inner surface of the rear end of the first cavity is fixedly connected to a first spring, the outer surface of the front end of the first spring is fixedly connected to the first limiting column, the outer surface of the lower end of the first nut is fixedly connected to a rubber column, the outer surface of the lower end of the rubber column is fixedly connected to a rubber block, and the outer surface of the lower end of the first nut is movably connected to a rubber pad.

[0008] The above technical solution further includes:

[0009] The outer surface of the upper end of the fixing column is fixedly connected to a third nut, the outer circular surface of the third nut is fixedly connected to a third fixing block, the left outer surface of the third fixing block is provided with a first limiting groove, the front outer surface of the third fixing block is inserted and connected to a fourth fixing block, the left outer surface of the fourth fixing block is provided with a second limiting groove, the left outer surface of the third fixing block is inserted and connected to a third limiting rod, the rear end outer surface of the third limiting rod is inserted and connected to a second spring, the rear end outer surface of the second spring is fixedly connected to the second limiting column, and the front end outer surface of the fourth fixing block is fixedly connected to the connecting block.

[0010] The outer circular surface of the fixed column is movably connected with the inner circular surface of the through hole, the outer surface of the upper end of the first limiting rod is movably connected with the outer surface of the lower end of the second threaded column, the outer circular surface of the fixed column is fixedly connected with the inner circular surface of the second threaded column, the number of the first fixed blocks and the rotating blocks are both several, the several first fixed blocks and the rotating blocks are all located on both sides of the second nut, and they are symmetrically distributed in pairs, the number of the rotating column, the second fixed plate and the second limiting rod are all two, the two rotating columns, the second fixed plates and the second limiting rods are all located at the rotating block positions on both sides of the second nut, and they are symmetrically distributed.

[0011] The number of the second fixing blocks is several, and the several second fixing blocks are located on both sides of the outer surface of the upper end of the first nut and are symmetrically distributed with each other, and they are connected to the second limiting rod sleeve, and the number of the first first cavity, the first cavity, the first spring and the first limiting column is several, and the several first first cavity, the first cavity, the first spring and the first limiting column are located in front and behind the second limiting rod and are symmetrically distributed with each other.

[0012] The number of the third fixed block, the fourth fixed block and the connecting block are all two, the two third fixed blocks, the fourth fixed block and the connecting block are all located on both sides of the third nut, and are symmetrically distributed with each other, the number of the first limiting grooves and the second limiting grooves are both several, and the several first limiting grooves and the second limiting grooves are respectively movably connected to each other, the number of the second springs and the second limiting columns are both several, and the several second springs and the second limiting columns are all located on the side of the third limiting rod away from the connecting block, and are symmetrically distributed with each other.

[0013] A combined bolt assembly and an installation and use method thereof, the specific steps are:

[0014] S1: Place the first threaded column and the second threaded column in the positions to be fixed;

[0015] S2: Rotate the rotating column by means of the rotating block on the first fixed block;

[0016] S3: moving the second limiting rod to the second fixed block position by rotating the column;

[0017] S4: The first spring on the second limiting rod and the first limiting column are squeezed through the first first cavity to fix the first threaded column on the first nut and the second threaded column on the second nut;

[0018] S5: After the bolt assembly is fixed, the first spring is retracted through the first limiting rod, and the second limiting rod is pulled out of the second fixing block, so that the first threaded column and the second threaded column do not rotate at the same time;

[0019] S6: The third limiting rod is pulled out from the third fixing block and the fourth fixing block by compressing the spring through the second limiting column;

[0020] S7: After the third limiting rod is pulled out, the fourth fixing block is inserted into the third fixing block;

[0021] S8: When the third fixing block and the fourth fixing block are moved to a required length, the first limiting groove and the second limiting groove are overlapped, and the third limiting rod is inserted to fix them;

[0022] S9: The bolt assembly is driven to rotate by contacting the connecting block to install and fix it.

[0023] The above technical solution further includes:

[0024] In S4, the first limiting posts on the plurality of first springs are pressed simultaneously.

[0025] In S8, the third fixing block and the fourth fixing block control the length of the required disassembly.

[0026] The present invention has the following beneficial effects:

[0027] 1. In the present invention, the first threaded column and the second threaded column can be conveniently separated by the second fixing block and the first spring and the first limiting column on the second limiting rod when used, so that it is not convenient to rotate them at the same time, and the bolt assembly will not touch and rotate and fall off during fixing.

[0028] 2. In the present invention, the first limiting groove and the second limiting groove on the third fixing block and the fourth fixing block are fixed by the third limiting rod, so that tools of different sizes can be used to install and disassemble the bolt assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A combined bolt assembly and an installation and use method thereof proposed by the present invention;

[0030] Figure 2 It is a schematic diagram of the positional relationship structure of the first fixed block, the rotating block and the rotating column in the present invention;

[0031] Figure 3 It is a schematic diagram of the structure of the second limiting rod and the second fixing block in the present invention;

[0032] Figure 4 It is a schematic diagram of the structural relationship between the positions of the first spring and the first limiting column in the present invention;

[0033] Figure 5 It is a schematic diagram of the bottom structure in the present invention;

[0034] Figure 6 It is a schematic diagram of the position relationship structure between the third fixing block and the third limiting rod in the present invention;

[0035] Figure 7It is a schematic structural diagram of the position relationship between the rubber column and the rubber block in the present invention;.

[0036] In the figure: 1. first nut; 2. first threaded column; 3. second threaded column; 4. fixed column; 5. second nut; 6. first limiting rod; 7. first fixed block; 8. rotating block; 9. rotating column; 10. fixed plate; 11. second limiting rod; 12. second fixed block; 13. slide groove; 14. first cavity; 15. first spring; 16. first limiting column; 17. through hole; 18. rubber column; 19. rubber block; 20. rubber pad; 21. third nut; 22. third fixed block; 23. first limiting groove; 24. fourth fixed block; 25. second limiting groove; 26. third limiting rod; 27. second spring; 28. second limiting column; 29. ​​connecting block. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Embodiment 1

[0039] like Figure 1-Figure 7 As shown, a combined bolt assembly proposed by the present invention includes a first nut 1, a first threaded column 2 is fixedly connected to the outer surface of the lower end of the first nut 1, a second threaded column 3 is movably connected to the outer surface of the lower end of the first threaded column 2, a through hole 17 is opened on the outer surface of the upper end of the first nut 1, the outer surface of the upper end of the first nut 1 is plugged and connected with a fixed column 4, a second nut 5 is fixedly connected to the outer surface of the upper end of the fixed column 4, a first limiting rod 6 is fixedly connected to the outer surface of the lower end of the fixed column 4, a first fixed block 7 is fixedly connected to the outer surface of the second nut 5, a rotating block 8 is fixedly installed on the outer surface of the rear end of the first fixed block 7, and a rotating column 9 is rotatably connected to the outer surface of the rear end of the rotating block 8. A fixing plate 10 is fixedly connected to the outer circular surface of the column 9, a second limiting rod 11 is fixedly connected to the left outer surface of the fixing plate 10, a sliding groove 13 is provided on the left outer surface of the second fixing block 12, the upper outer surface of the first nut 1 is fixedly connected to the second fixing block 12, a first cavity 14 is provided on the front outer surface of the second limiting rod 11, a first spring 15 is fixedly connected to the rear inner surface of the first cavity 14, a first limiting column 16 is fixedly connected to the front outer surface of the first spring 15, a rubber column 18 is fixedly connected to the lower outer surface of the first nut 1, a rubber block 19 is fixedly connected to the lower outer surface of the rubber column 18, and a rubber pad 20 is movably connected to the lower outer surface of the first nut 1.

[0040] In one embodiment, a third nut 21 is fixedly connected to the outer surface of the upper end of the fixing column 4, a third fixing block 22 is fixedly connected to the outer cylindrical surface of the third nut 21, a first limiting groove 23 is provided on the left outer surface of the third fixing block 22, a fourth fixing block 24 is inserted and connected to the front outer surface of the third fixing block 22, a second limiting groove 25 is provided on the left outer surface of the fourth fixing block 24, a third limiting rod 26 is inserted and connected to the left outer surface of the third fixing block 22, a second spring 27 is inserted and connected to the rear end outer surface of the third limiting rod 26, a second limiting column 28 is fixedly connected to the rear end outer surface of the second spring 27, and a connecting block 29 is fixedly connected to the front end outer surface of the fourth fixing block 24.

[0041] In one embodiment, the outer cylindrical surface of the fixing column 4 is movably connected to the inner cylindrical surface of the through hole 17, the upper outer surface of the first limiting rod 6 is movably connected to the lower outer surface of the second threaded column 3, and the outer cylindrical surface of the fixing column 4 is fixedly connected to the inner cylindrical surface of the second threaded column 3.

[0042] In one embodiment, the number of the first fixed blocks 7 and the number of the rotating blocks 8 are both multiple, and the multiple first fixed blocks 7 and the rotating blocks 8 are both located on both sides of the second nut 5, and are symmetrically distributed in pairs.

[0043] In one embodiment, the number of the rotating column 9, the second fixing plate 10 and the second limiting rod 11 are all two, and the two rotating columns 9, the second fixing plate 10 and the second limiting rod 11 are all located at the rotating block 8 on both sides of the second nut 5, and are symmetrically distributed with each other.

[0044] In one embodiment, the number of second fixing blocks 12 is several, and the several second fixing blocks 12 are all located on both sides of the outer surface of the upper end of the first nut 1 and are symmetrically distributed with each other, and they are sleeved and connected with the second limiting rod 11, and the number of the first first cavity 14, the first cavity 14, the first spring 15 and the first limiting column 16 is several, and the several first first cavities 14, the first cavity 14, the first spring 15 and the first limiting column 16 are all located in front and behind the second limiting rod 11 and are symmetrically distributed with each other.

[0045] In one embodiment, the number of the third fixing block 22, the fourth fixing block 24 and the connecting block 29 are all two, the two third fixing blocks 22, the fourth fixing block 24 and the connecting block 29 are all located on both sides of the third nut 21, and are symmetrically distributed with each other, the number of the first limiting grooves 23 and the second limiting grooves 25 are both several, and the several first limiting grooves 23 and the second limiting grooves 25 are respectively movably connected to each other, the number of the second springs 27 and the second limiting columns 28 are both several, and the several second springs 27 and the second limiting columns 28 are all located on the side of the third limiting rod 26 away from the connecting block 29, and are symmetrically distributed with each other.

[0046] The working principle of a combined bolt assembly proposed by the present invention is as follows: the first threaded column 2 and the second threaded column 3 are placed in the positions to be fixed, the rotating column 9 is rotated by the rotating block 8 on the first fixing block 7, the second limiting rod 11 is moved to the position of the second fixing block 12 by the rotating column 9, the first spring 15 and the first limiting column 16 on the second limiting rod 11 are squeezed through the first first cavity 14, the first threaded column 2 on the first nut 1 and the second threaded column 3 on the second nut 5 are fixed, after the bolt assembly is fixed, the first spring 15 is retracted by the first limiting rod 6, and the second limiting rod 16 is pressed through the first first cavity 14, The rod 11 pulls out the second fixing block 12, so that the first threaded column 2 and the second threaded column 3 do not rotate at the same time. The third limiting rod 26 is pulled out from the third fixing block 22 and the fourth fixing block 24 by squeezing the spring through the second limiting column 28. After the third limiting rod 26 is pulled out, the fourth fixing block 24 is inserted into the third fixing block 22. When the third fixing block 22 and the fourth fixing block 24 are moved to the required length, the first limiting groove 23 is overlapped with the second limiting groove 25, and the third limiting rod 26 is inserted to fix it. The bolt assembly is driven to rotate by contacting the connecting block 29 to install and fix it.

[0047] A combined bolt assembly and an installation and use method thereof, the specific steps are:

[0048] S1: Place the first threaded column 2 and the second threaded column 3 in positions where they need to be fixed;

[0049] S2: Rotate the rotating column 9 through the rotating block 8 on the first fixed block 7;

[0050] S3: Move the second limiting rod 11 to the position of the second fixing block 12 by rotating the column 9;

[0051] S4: The first spring 15 and the first limiting column 16 on the second limiting rod 11 are squeezed through the first first cavity 14 to fix the first threaded column 2 on the first nut 1 and the second threaded column 3 on the second nut 5;

[0052] S5: After the bolt assembly is fixed, the first spring 15 is retracted through the first limiting rod 6, and the second limiting rod 11 is pulled out of the second fixing block 12, so that the first threaded column 2 and the second threaded column 3 do not rotate at the same time;

[0053] S6: The third limiting rod 26 is pulled out from the third fixing block 22 and the fourth fixing block 24 by squeezing the spring through the second limiting column 28;

[0054] S7: After the third limiting rod 26 is pulled out, the fourth fixing block 24 is inserted into the third fixing block 22;

[0055] S8: When the third fixing block 22 and the fourth fixing block 24 are moved to a required length, the first limiting groove 23 and the second limiting groove 25 are overlapped, and the third limiting rod 26 is inserted to fix them;

[0056] S9: The bolt assembly is driven to rotate by contacting the connecting block 29 to install and fix it.

[0057] In one embodiment, in S4, the first limiting posts 16 on the plurality of first springs 15 are pressed simultaneously.

[0058] In one embodiment, in S8, the third fixing block and the fourth fixing block control the length of the required disassembly.

[0059] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A combined bolt assembly, comprising a first nut (1), characterized in that: The first nut (1) is fixedly connected to a first threaded column (2) on the outer surface of the lower end, and the second threaded column (3) is movably connected to the outer surface of the lower end of the first threaded column (2). A through hole (17) is provided on the outer surface of the upper end of the first nut (1). The outer surface of the upper end of the first nut (1) is plug-connected with a fixed column (4). The second nut (5) is fixedly connected to the outer surface of the upper end of the fixed column (4). The first limiting rod (6) is fixedly connected to the outer surface of the lower end of the fixed column (4). The second nut (5) is fixedly connected to a first fixed block (7) on the outer surface of the rear end of the first fixed block (7). A rotating block (8) is fixedly installed on the outer surface of the rear end of the rotating block (8). A rotating column (9) is rotatably connected to the outer surface of the rear end of the rotating block (8). The outer surface of the rotating column (9) is fixedly connected to a fixed The fixing plate (10) is fixedly connected to a second limiting rod (11) on the left outer surface of the fixing plate (10), a sliding groove (13) is provided on the left outer surface of the second fixing block (12), the upper outer surface of the first nut (1) is fixedly connected to the second fixing block (12), the front outer surface of the second limiting rod (11) is provided with a first cavity (14), the rear inner surface of the first cavity (14) is fixedly connected to a first spring (15), the front outer surface of the first spring (15) is fixedly connected to a first limiting column (16), the lower outer surface of the first nut (1) is fixedly connected to a rubber column (18), the lower outer surface of the rubber column (18) is fixedly connected to a rubber block (19), and the lower outer surface of the first nut (1) is movably connected to a rubber pad (20).

2. A combined bolt assembly according to claim 1, characterized in that: The upper outer surface of the fixing column (4) is fixedly connected with a third nut (21), the outer cylindrical surface of the third nut (21) is fixedly connected with a third fixing block (22), the left outer surface of the third fixing block (22) is provided with a first limiting groove (23), the front outer surface of the third fixing block (22) is plugged and connected with a fourth fixing block (24), the left outer surface of the fourth fixing block (24) is provided with a second limiting groove (25), the left outer surface of the third fixing block (22) is plugged and connected with a third limiting rod (26), the rear outer surface of the third limiting rod (26) is plugged and connected with a second spring (27), the rear outer surface of the second spring (27) is fixedly connected with a second limiting column (28), and the front outer surface of the fourth fixing block (24) is fixedly connected with a connecting block (29).

3. A combined bolt assembly according to claim 1, characterized in that: The outer circular surface of the fixing column (4) is movably connected to the inner circular surface of the through hole (17), the outer surface of the upper end of the first limiting rod (6) is movably connected to the outer surface of the lower end of the second threaded column (3), and the outer circular surface of the fixing column (4) is fixedly connected to the inner circular surface of the second threaded column (3).

4. A combined bolt assembly according to claim 1, characterized in that: The number of the first fixed blocks (7) and the number of the rotating blocks (8) are both multiple, and the multiple first fixed blocks (7) and the rotating blocks (8) are both located on both sides of the second nut (5), and are symmetrically distributed in pairs.

5. The combined bolt assembly according to claim 1, characterized in that: The number of the rotating column (9), the second fixing plate (10) and the second limiting rod (11) is two, and the two rotating columns (9), the second fixing plate (10) and the second limiting rod (11) are both located at the positions of the rotating blocks (8) on both sides of the second nut (5), and are symmetrically distributed with respect to each other.

6. A combined bolt assembly according to claim 1, characterized in that: The number of the second fixing blocks (12) is multiple, and the multiple second fixing blocks (12) are all located on both sides of the outer surface of the upper end of the first nut (1) and are symmetrically distributed with each other, and are sleeved and connected with the second limiting rod (11); the number of the first first cavity (14), the first cavity (14), the first spring (15) and the first limiting column (16) are all multiple, and the multiple first first cavity (14), the first cavity (14), the first spring (15) and the first limiting column (16) are all located in front of and behind the second limiting rod (11) and are symmetrically distributed with each other.

7. A combined bolt assembly according to claim 2, characterized in that: The number of the third fixing block (22), the fourth fixing block (24) and the connecting block (29) is two, and the two third fixing blocks (22), the fourth fixing block (24) and the connecting block (29) are all located on both sides of the third nut (21), and are symmetrically distributed with respect to each other. The number of the first limiting groove (23) and the second limiting groove (25) is multiple, and the multiple first limiting grooves (23) and the second limiting grooves (25) are respectively movably connected with each other. The number of the second springs (27) and the second limiting columns (28) is multiple, and the multiple second springs (27) and the second limiting columns (28) are all located on the side of the third limiting rod (26) away from the connecting block (29), and are symmetrically distributed with respect to each other.

8. A method for installing and using a combined bolt assembly according to any one of claims 1 to 7, characterized in that: The specific steps are: S1: Place the first threaded column (2) and the second threaded column (3) at positions where they need to be fixed; S2: rotating the rotating column (9) by means of the rotating block (8) on the first fixed block (7); S3: moving the second limiting rod (11) to the position of the second fixing block (12) by rotating the column (9); S4: The first spring (15) and the first limiting column (16) on the second limiting rod (11) are squeezed through the first first cavity (14) to fix the first threaded column (2) on the first nut (1) and the second threaded column (3) on the second nut (5); S5: After the bolt assembly is fixed, the first spring (15) is retracted through the first limiting rod (6), and the second limiting rod (11) is pulled out of the second fixing block (12), so that the first threaded column (2) and the second threaded column (3) do not rotate at the same time; S6: The third limiting rod (26) is pulled out from the third fixing block (22) and the fourth fixing block (24) by compressing the spring through the second limiting column (28); S7: After the third limiting rod (26) is pulled out, the fourth fixing block (24) is inserted into the third fixing block (22); S8: When the third fixing block (22) and the fourth fixing block (24) are moved to a required length, the first limiting groove (23) and the second limiting groove (25) are overlapped, and the third limiting rod (26) is inserted to fix them; S9: The bolt assembly is driven to rotate by contacting the connecting block (29) to install and fix it.

9. The method for installing and using a combined bolt assembly according to claim 8, characterized in that: In S4, the first limiting posts (16) on the plurality of first springs (15) are pressed simultaneously.

10. The method for installing and using a combined bolt assembly according to claim 8, characterized in that: In S8, the third fixing block (22) and the fourth fixing block (24) control the length of disassembly required.

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