CN114497868A

CN114497868A - Locking mechanism

Info

Publication number: CN114497868A
Application number: CN202210089792.9A
Authority: CN
Inventors: 李扬; 李鸿键; 侯艳丽; 李玉军
Original assignee: Beijing Shengneng Energy Technology Co Ltd
Current assignee: Beijing Shengneng Energy Technology Co Ltd
Priority date: 2022-01-25
Filing date: 2022-01-25
Publication date: 2022-05-13

Abstract

The invention relates to the technical field of automobiles, and discloses a locking mechanism which comprises a nut component and a bolt component. The nut assembly comprises a nut and a fixed sleeve, and the nut can move relative to the fixed sleeve; the bolt assembly comprises a shell, a bolt and a transmission part, wherein the bolt and the transmission part are arranged in the shell, and the bolt can enable the nut to move relative to the fixed sleeve by abutting against the nut and enable the bolt to move relative to the shell; the transmission piece is sleeved on the bolt, the shell is used for limiting the rotation of the transmission piece at the locking position, the transmission piece can move along the axial direction of the bolt to leave the locking position, and the transmission piece leaving the locking position can drive the bolt to rotate so as to enable the bolt to be in threaded connection with the nut; still include the elastic component, the elastic component cover is located on the bolt, spacing arch on the one end butt bolt of elastic component, other end butt driving medium. Make bolt butt nut earlier with this, the adjustment nut position, reuse driving medium and the coaxial rotation of bolt make nut and bolt threaded connection, realize the quick replacement of battery package high accuracy.

Description

Locking mechanism

Technical Field

The invention relates to the technical field of automobiles, in particular to a locking mechanism.

Background

With the development of new energy electric vehicle technology in China, users have higher requirements on the endurance mileage and the charging time of electric vehicles, but due to the characteristics of an electric core system and a battery, the electric vehicles cannot be charged in a short time to reach a larger endurance mileage at present, and when the battery quick charging technology cannot be further improved, the quick replacement of a battery pack of the electric vehicles becomes more important.

Several locking mechanisms commonly used in the current battery pack replacement scheme mainly comprise a buckle type locking mechanism, a tension type locking mechanism and a screwing type locking mechanism, but the locking mechanisms still have the following defects in the use process, for example, the buckle type locking mechanism is large in abrasion in the use process, easy to block and needs to be maintained manually frequently; the tension type locking mechanism has more parts, complex structure, high requirement on the matching performance of the battery pack, poor compatibility and higher cost of a single piece; and the screwing type locking mechanism has poor compatibility, no tolerance capability, easy damage of parts and short service life.

Therefore, a locking mechanism is needed to solve the above problems.

Disclosure of Invention

The invention aims to provide a locking mechanism which is simple in structure, capable of realizing quick replacement of a battery pack, high in compatibility and capable of effectively improving the installation accuracy of the battery pack.

As the conception, the technical scheme adopted by the invention is as follows:

a locking mechanism, comprising:

the nut assembly comprises a nut and a fixing sleeve, and the nut can move relative to the fixing sleeve;

the bolt assembly comprises a shell, a bolt and a transmission part, wherein the bolt and the transmission part are arranged in the shell, and the bolt can abut against the nut to enable the nut to move relative to the fixed sleeve and enable the bolt to move relative to the shell; the transmission piece is sleeved on the bolt, the shell is used for limiting the rotation of the transmission piece at a locking position, the transmission piece can move along the axial direction of the bolt to leave the locking position, and the transmission piece leaving the locking position can drive the bolt to rotate so as to enable the bolt to be in threaded connection with the nut; still include the elastic component, the elastic component cover is located on the bolt, the one end butt of elastic component spacing arch on the bolt, the other end butt the driving medium.

Optionally, the casing includes installation shell and spacing base, the installation shell with spacing base is connected in order to form the installation cavity, be provided with the transmission hole on the spacing base, the installation shell deviates from one side of spacing base is provided with the mounting hole, the bolt with the driving medium set up in the installation cavity, just the driving medium is not connected the one end of bolt is stretched out the transmission hole, the bolt is not connected the one end of driving medium can stretch out the mounting hole.

Optionally, the bolt orientation the one end of driving medium is provided with first transmission portion, the driving medium orientation the one end of bolt is provided with second transmission portion, the driving medium cover is located on the bolt, first transmission portion with second transmission portion butt, so that the bolt with the driving medium has coaxial rotation.

Optionally, the inner wall of the transmission hole is provided with a first limiting portion, the outer peripheral surface of the transmission member is provided with a second limiting portion, and the first limiting portion is abutted against the second limiting portion to limit the rotation of the transmission member at the locking position.

Optionally, still be provided with spacing step on the driving medium, spacing step set up in second transmission portion keeps away from one side of bolt, the transmission hole has the ladder face, spacing step is located the installation intracavity and can the butt in the ladder face.

Optionally, the inner wall of the transmission hole, which is provided with one end of the second limiting part, is provided with a chamfer.

Optionally, the locking mechanism still includes the bolster, the bolster cover is located on the bolt and butt spacing arch deviates from the one side of driving medium.

Optionally, the bolt abuts against the periphery of one end of the nut and is provided with a chamfer.

Optionally, fixed cover has the holding chamber, fixed cover still sets up the intercommunication the spacing hole in holding chamber, the nut includes nut body and the spacing portion of nut, the nut body set up in the holding intracavity, the spacing portion of nut passes through spacing hole stretches out outside the holding chamber, the outer peripheral face of the spacing portion of nut with the clearance has between the inner wall in spacing hole, the outer peripheral face of nut body with the clearance has between the inner wall in holding chamber.

Optionally, the fixing sleeve is further provided with a fixing hole, the fixing hole and the limiting hole are oppositely arranged along the axial direction of the nut, and the bolt penetrates through the fixing hole to be connected with the nut.

The invention has the beneficial effects that:

the locking mechanism provided by the invention comprises a bolt assembly and a nut assembly. Wherein the nut assembly comprises a nut and a fixing sleeve, and the nut can move relative to the fixing sleeve. And bolt assembly includes casing, bolt, elastic component and driving medium, and bolt, elastic component and driving medium all set up in the casing, and on the bolt was located to driving medium and elastic component all overlap, and the spacing arch on the one end butt bolt of elastic component, other end butt driving medium can realize the adjustment of driving medium and bolt relative position on the axial direction of bolt promptly through compressing the elastic component. In addition, the casing still is used for restricting the rotation of driving medium in the locking position, and when the axial displacement of driving medium along the bolt, the driving medium just can leave this locking position, and when the driving medium left the locking position, the driving medium will drive the bolt and rotate to make the bolt wear to locate in the nut and threaded connection. When the bolt can not rotate, the nut can move relative to the fixed sleeve by abutting the bolt against the nut, and the bolt moves relative to the shell.

Under this setting, can utilize the relative movement of driving medium and the bolt that is in the locking position earlier, the relative position of adjustment nut and fixed cover makes nut and bolt central line coincidence, makes the driving medium leave the locking position again, utilizes the coaxial removal of driving medium and bolt to realize the threaded connection of bolt and nut. When the locking mechanism is used, the nut assembly can be fixed on the automobile body, the bolt assembly is connected with the battery pack, the battery pack and the automobile body can be quickly disassembled and assembled, and the installation accuracy of the battery pack can be improved.

Drawings

FIG. 1 is a cross-sectional view of a locking mechanism provided by an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a locking mechanism provided in an embodiment of the present invention;

FIG. 3 is a schematic view of the assembly of a bolt and a transmission member provided in an embodiment of the present invention;

FIG. 4 is a schematic view of the assembly of the bolt, the transmission member and the limiting base provided by the embodiment of the invention;

FIG. 5 is a schematic structural diagram of a bolt provided in an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a limiting base provided in the embodiment of the present invention;

fig. 7 is a schematic structural view of a fixing sleeve provided in an embodiment of the present invention.

In the figure:

1. a nut; 11. a nut body; 12. a nut limiting part;

2. fixing a sleeve; 20. an accommodating cavity; 21. a limiting hole; 22. a fixing hole;

3. a housing; 30. a mounting cavity; 31. mounting a shell; 32. a limiting base; 321. a first limiting part; 322. a step surface;

4. a bolt; 41. a limiting bulge; 42. a first transmission unit; 43. a threaded portion;

5. a transmission member; 51. a second limiting part; 52. a second transmission part; 53. a limiting step;

6. an elastic member.

Detailed Description

In order to make the technical problems solved, the technical solutions adopted and the technical effects achieved by the present invention clearer, the technical solutions of the present invention are further described below by way of specific embodiments with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. It should be further noted that, for the convenience of description, only some but not all of the elements associated with the present invention are shown in the drawings.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "left", "right", and the like are used based on the orientations and positional relationships shown in the drawings only for convenience of description and simplification of operation, and do not indicate or imply that the referred device or element must have a specific orientation, be configured and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

For realizing the quick replacement of battery package, as shown in fig. 1-7, this embodiment provides a locking mechanism, including nut assembly and bolt assembly, wherein nut assembly can be fixed in the automobile body, and bolt assembly can be fixed in the battery package, and through bolt assembly and nut assembly's cooperation, can realize the demountable installation of battery package and automobile body, it is quick convenient, and positioning accuracy is high.

As shown in fig. 1, the nut assembly comprises a nut 1 and a fixing sleeve 2, wherein the nut 1 can move relative to the fixing sleeve 2 and is connected with the automobile body through the fixing sleeve 2. And bolt assembly includes casing 3, bolt 4, elastic component 6 and driving medium 5, and wherein bolt 4, elastic component 6 and driving medium 5 all set up in casing 3, and on driving medium 5 and elastic component 6 all overlapped locate bolt 4, and the spacing arch 41 on the one end butt bolt 4 of elastic component 6, other end butt driving medium 5, through compressing elastic component 6 with the relative position of adjustment driving medium 5 and bolt 4 on the axial direction of bolt 4 promptly. In addition, the casing 3 is also used for limiting the rotation of the transmission member 5 at the locking position, and when the transmission member 5 moves along the axial direction of the bolt 4, the transmission member 5 can leave the locking position, and when the transmission member 5 leaves the locking position, the transmission member 5 can drive the bolt 4 to rotate, so that the bolt 4 is arranged in the nut 1 in a penetrating manner, and the threaded connection between the bolt 4 and the nut 1 is realized. When the bolt 4 cannot be rotated, the nut 1 is moved relative to the fixing sleeve 2 by the bolt 4 abutting against the nut 1, and the bolt 4 is moved relative to the housing 3.

That is to say, when the transmission element 5 is in the locking position, neither the transmission element 5 nor the screw bolt 4 can rotate, and the transmission element 5 and the screw bolt 4 can only be moved in the axial direction of the screw bolt 4 by an external force. When the external force for driving the bolt 4 to move is that the bolt 4 abuts against the nut 1, the nut 1 gives a reaction force to the bolt 4, and the reaction force enables the bolt 4 to move toward the side close to the transmission member 5. The external force driving the transmission member 5 to move is an external driving force, i.e. the external driving force abuts against the transmission member 5 to move the transmission member 5 toward the side close to the bolt 4, and the transmission member 5 can be moved away from the locking position by the driving force.

As shown in fig. 3, the coaxial rotation of the transmission member 5 and the bolt 4 is realized by the abutment of a first transmission portion 42 provided on the bolt 4 and a second transmission portion 52 provided on the transmission member 5, the first transmission portion 42 is provided at one end of the bolt 4 facing the transmission member 5, and the second transmission portion 52 is provided at one end of the transmission member 5 facing the bolt 4. The driving member 5 is sleeved on the bolt 4, i.e. the driving member 5 is connected to one end of the bolt 4 and is required to be provided with a guide hole, and the bolt 4 is inserted into the guide hole to be connected with the driving member 5, so that the first transmission portion 42 is arranged on the outer peripheral surface of the bolt 4, and the second transmission portion 52 is arranged on the hole wall of the guide hole. Alternatively, the first transmission portion 42 is of an externally splined configuration and the second transmission portion 52 is of an internally splined configuration.

Further, as shown in fig. 1 to 4, in this embodiment, the housing 3 includes an installation shell 31 and a limiting base 32, the installation shell 31 is connected with the limiting base 32 to form an installation cavity 30, a transmission hole is formed in the limiting base 32, an installation hole is formed in one side of the installation shell 31 away from the limiting base 32, the bolt 4 and the transmission member 5 are arranged in the installation cavity 30, the transmission hole is extended from one end of the transmission member 5 not connected with the bolt 4, and the installation hole can be extended from one end of the bolt 4 not connected with the transmission member 5. Optionally, installation shell 31 and limiting base 32 utilize the fastener can dismantle the connection, when the installation, can place the bolt 4 that the cover was equipped with elastic component 6 in installation cavity 30 earlier to make it stretch out through the mounting hole portion, then locate bolt 4 with driving medium 5 cover again on, install limiting base 32 again at last, limiting base 32 not only can restrict the rotation of driving medium 5 in the locking position, still can avoid driving medium 5 to break away from casing 3.

Specifically, as shown in fig. 3 and 4, the inner wall of the transmission hole is provided with a first limiting portion 321, and the outer peripheral surface of the transmission member 5 is provided with a second limiting portion 51, so that when the first limiting portion 321 abuts against the second limiting portion 51, the transmission member 5 cannot rotate relative to the transmission hole. Alternatively, the first stopper portion 321 is an internal gear structure, and the second stopper portion 51 is an external gear structure. Since the housing 3 is connected to the battery pack and does not rotate, the transmission member 5 is in the locking position when the transmission member 5 is engaged with the mounting housing 31 through the gear structure.

Optionally, the inner wall of the end of the transmission hole, where the second limiting portion 51 is disposed, is provided with a chamfer, and the chamfer on the hole wall is configured to provide a guiding function for the axial movement of the transmission member 5 relative to the transmission hole.

As shown in fig. 6, the transmission member 5 is provided with a limiting step 53, the limiting step 53 is disposed on one side of the second transmission portion 52 away from the bolt 4, the inner wall of the transmission hole has a stepped surface 322, when the bolt 4 is pressed by the nut 1 to move toward one side close to the transmission member 5, the bolt 4 can drive the transmission member 5 to move in the same direction through the elastic member 6, when the limiting step 53 located in the installation cavity 30 is pressed against the stepped surface 322, the movement of the transmission member 5 is limited, and if the bolt 4 continues to move toward one side of the transmission member 5, only the elastic member 6 can be compressed. Alternatively, the transmission hole may be partitioned into a first transmission hole and a second transmission hole by the stepped surface 322, and the transmission member 5 may be partitioned into an inner transmission member and an outer transmission member by the limit step 53. Wherein the outer gear structure sets up in the outer peripheral face of interior driving medium, and the inner gear structure sets up on the inner wall in transmission one hole, and two holes of transmission are worn to locate by outer driving medium, and stretch out installation cavity 30 through two holes of transmission.

Optionally, the shape of the outer transmission member may be selected according to actual conditions, and in this embodiment, the outer transmission member is configured to be a hexahedral structure, so as to facilitate clamping of the external device. In addition, as shown in fig. 5, in the embodiment, the bolt 4 is connected with the nut 1 through the thread portion 43, so if the bolt 4 needs to be adjusted according to the requirements of different battery packs, the bolt 4 with the different structure of the thread portion 43 can be selected, so that the transmission piece 5 does not need to be replaced, and the operation is more convenient and the cost is saved.

Furthermore, the locking mechanism further includes a buffer member, the buffer member is sleeved on the bolt 4, and abuts against one surface of the limiting protrusion 41 departing from the transmission member 5. Optionally, the buffer is a lubricating washer, which may be bonded to the spacing protrusion 41. In this embodiment, the limiting protrusion 41 is an annular protrusion annularly provided on the body of the bolt 4, and has a cross-sectional shape consistent with that of the lubricating washer. Bolt 4 removes under the drive of elastic component 6, driving medium 5, and spacing arch 41 will be through bolster butt installation shell 31 inner wall, can effectively alleviate the striking of bolt 4 to installation shell 31.

Finally, it should be noted that, as shown in fig. 7, the specific structure of the nut assembly, the fixing sleeve 2 has an accommodating cavity 20 and a limiting hole 21 communicating with the accommodating cavity 20, the nut 1 includes a nut body 11 and a nut limiting portion 12, the nut body 11 is located in the accommodating cavity 20, the nut limiting portion 12 extends out of the accommodating cavity 20 through the limiting hole 21, a gap is formed between an outer peripheral surface of the nut limiting portion 12 and an inner wall of the limiting hole 21, and a gap is also formed between an outer peripheral surface of the nut body 11 and an inner wall of the accommodating cavity 20, that is, the nut 1 and the fixing sleeve 2 are in clearance fit, and the fixing sleeve 2 can be fixed to the automobile body, so that when an external force is applied, the nut 1 can move relative to the fixing sleeve 2 to achieve the guiding effect of the bolt 4 on the nut 1, and the center lines of the bolt 4 and the nut 1 coincide.

Optionally, the fixing sleeve 2 is further provided with a fixing hole 22, the fixing hole 22 is disposed opposite to the limiting hole 21 along the axial direction of the nut 1, and the bolt 4 can pass through the fixing hole 22 to be connected with the nut 1. In this embodiment, the fixing sleeve 2 is formed by bending a plate, the fixing hole 22 is formed in the center of the plate before bending, two limiting half holes are formed at two ends of the plate, and the two limiting half holes can be spliced to form the limiting hole 21 after the plate is bent.

Therefore, when the locking mechanism provided by the embodiment is used for mounting the battery pack with the bolt assembly on the automobile body with the nut assembly, the following two steps are mainly included: wherein the first step is, make the bolt assembly be located preset position when utilizing positioning system, then utilize external equipment drive bolt assembly to be close to the nut assembly, driving medium 5 receives the restriction of casing 3 this moment, can not drive bolt 4 and rotate, therefore when bolt 4 butt nut 1, even bolt 4 is coaxial with nut 1, then bolt 4 still can not wear to locate in nut 1, can only butt in the terminal surface of nut 1, and along with the bolt assembly constantly is close to the nut assembly, bolt 4 will receive driving about of the reaction force that nut 1 gave, compression elastic component 6, in order to remove to the direction that is close to driving medium 5. When the housing 3 abuts the nut assembly, the bolt 4 will be fully located within the housing 3. On the contrary, for the nut 1, the main function of the first step is to enable the nut 1 to move relative to the fixed sleeve 2 by means of the interaction force between the bolt 4 and the nut 1, so as to compensate for possible positioning errors of the positioning system. That is, if a positioning error exists, a small-range deviation may exist between the center lines of the bolt 4 and the nut 1, when the bolt 4 abuts against the nut 1, although the bolt 4 cannot be completely inserted into the nut 1 due to the arrangement of the threads on the bolt 4, the end of the bolt 4 can still play a certain guiding role in the movement of the nut 1 relative to the fixed sleeve 2, that is, the center lines of the nut 1 and the bolt 4 are overlapped by the first abutment of the bolt 4 and the nut 1, so that a foundation is laid for the subsequent connection of the bolt 4 and the nut 1.

Optionally, one end of the bolt 4 abutting the nut 1 is provided with a chamfer. The setting of chamfer makes bolt 4 still can have the fractional part to wear to locate in nut 1 when can not rotating, increases the butt area of bolt 4 and nut 1 to the guide effect that increase bolt 4 removed to nut 1.

Can begin the second step after guaranteeing the coincidence of the central line of bolt 4 and nut 1, utilize external equipment drive driving medium 5 to moving to the one side that is close to bolt 4, make driving medium 5 leave locking position, the driving medium 5 can drive bolt 4 and rotate this moment, pivoted bolt 4 can wear to locate in the nut 1 through screw drive to with this threaded connection who realizes bolt 4 and nut 1, the battery package is then installed on the automobile body so far.

The foregoing embodiments are merely illustrative of the principles and features of this invention, which is not limited to the above-described embodiments, but rather is susceptible to various changes and modifications without departing from the spirit and scope of the invention, which changes and modifications are within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A locking mechanism, comprising:

the nut assembly comprises a nut (1) and a fixing sleeve (2), and the nut (1) can move relative to the fixing sleeve (2);

the bolt assembly comprises a shell (3), and a bolt (4) and a transmission piece (5) which are arranged in the shell (3), wherein the bolt (4) can abut against the nut (1) to enable the nut (1) to move relative to the fixed sleeve (2) and enable the bolt (4) to move relative to the shell (3); the transmission piece (5) is sleeved on the bolt (4), the shell (3) is used for limiting the rotation of the transmission piece (5) at a locking position, the transmission piece (5) can move along the axial direction of the bolt (4) to leave the locking position, and the transmission piece (5) leaving the locking position can drive the bolt (4) to rotate so as to enable the bolt (4) to be in threaded connection with the nut (1); still include elastic component (6), elastic component (6) cover is located on bolt (4), the one end butt of elastic component (6) spacing arch (41) on bolt (4), the other end butt driving medium (5).

2. The locking mechanism according to claim 1, wherein the housing (3) comprises a mounting shell (31) and a limiting base (32), the mounting shell (31) and the limiting base (32) are connected to form a mounting cavity (30), a transmission hole is formed in the limiting base (32), a mounting hole is formed in one side, away from the limiting base (32), of the mounting shell (31), the bolt (4) and the transmission member (5) are arranged in the mounting cavity (30), one end, not connected with the bolt (4), of the transmission member (5) extends out of the transmission hole, and one end, not connected with the transmission member (5), of the bolt (4) can extend out of the mounting hole.

3. The locking mechanism according to claim 2, wherein a first transmission portion (42) is disposed at an end of the bolt (4) facing the transmission member (5), a second transmission portion (52) is disposed at an end of the transmission member (5) facing the bolt (4), the transmission member (5) is sleeved on the bolt (4), and the first transmission portion (42) and the second transmission portion (52) are abutted to enable the bolt (4) and the transmission member (5) to rotate coaxially.

4. The locking mechanism according to claim 3, wherein a first limiting portion (321) is disposed on an inner wall of the transmission hole, a second limiting portion (51) is disposed on an outer circumferential surface of the transmission member (5), and the first limiting portion (321) and the second limiting portion (51) are abutted to limit rotation of the transmission member (5) at the locking position.

5. The locking mechanism according to claim 3, characterized in that a limiting step (53) is further disposed on the transmission member (5), the limiting step (53) is disposed on a side of the second transmission portion (52) away from the bolt (4), the transmission hole has a stepped surface (322), and the limiting step (53) is located in the installation cavity (30) and can abut against the stepped surface (322).

6. The locking mechanism according to claim 4, characterized in that the inner wall of the transmission hole at the end where the second limiting part (51) is arranged is provided with a chamfer.

7. The locking mechanism according to claim 3, further comprising a buffer member, wherein the buffer member is sleeved on the bolt (4) and abuts against a surface of the limiting protrusion (41) facing away from the transmission member (5).

8. The locking mechanism according to claim 1, characterized in that the periphery of the bolt (4) abutting one end of the nut (1) is provided with a chamfer.

9. The locking mechanism according to claim 1, wherein the fixing sleeve (2) has a receiving cavity (20), the fixing sleeve (2) is further provided with a limiting hole (21) communicated with the receiving cavity (20), the nut (1) comprises a nut body (11) and a nut limiting portion (12), the nut body (11) is disposed in the receiving cavity (20), the nut limiting portion (12) extends out of the receiving cavity (20) through the limiting hole (21), a gap is formed between an outer peripheral surface of the nut limiting portion (12) and an inner wall of the limiting hole (21), and a gap is formed between an outer peripheral surface of the nut body (11) and the inner wall of the receiving cavity (20).

10. The locking mechanism according to claim 9, wherein a fixing hole (22) is further formed in the fixing sleeve (2), the fixing hole (22) and the limiting hole (21) are arranged opposite to each other in the axial direction of the nut (1), and the bolt (4) passes through the fixing hole (22) to connect the nut (1).