CN108443288B

CN108443288B - Fastening piece

Info

Publication number: CN108443288B
Application number: CN201710083961.7A
Authority: CN
Inventors: 孙愉后
Original assignee: Individual
Current assignee: Fujian Jinjiang Lijing Automotive Fittings Co ltd
Priority date: 2017-02-16
Filing date: 2017-02-16
Publication date: 2024-04-16
Anticipated expiration: 2037-02-16
Also published as: CN108443288A

Abstract

There is provided a fastener which is capable of being fastened, the fastener comprises a tightening piece (1) and a ring-shaped piece (2). The annular member comprises an annular second main body part (22), a flange part (21) and a plurality of first blocking protrusions (23) which are arranged at intervals, the first blocking protrusions axially extend from the flange part towards the second joint surface on the outer side of the second main body part, wherein the outer diameter of the first blocking protrusions is larger than the outer diameter of the tightening member; wherein the tightening member and the first blocking protrusion of the ring member are adapted to be coupled to a wrench device for synchronized disassembly and assembly of the tightening member and the ring member. The fastening piece of the invention is combined by the combining surface plays a role in inhibiting the tightening piece from loosening further. And damage to the joint surface during disassembly and assembly is avoided. The structure of the invention can avoid screwing the tightening piece back to the original position during the disassembly, thereby simplifying the operation.

Description

Fastening piece

Technical Field

The present invention relates to a fastener which suppresses further loosening of a tightening member by joining a joining surface of the tightening member and a ring member, and more particularly, to a fastener which can achieve simultaneous tightening or loosening of the tightening member and the ring member without damaging the joining surface therebetween, and a spanner device dedicated therefor.

Background

Fasteners are used in a wide variety of industries where there is a need for connection fastening, such as in vehicles, construction machines, farm machines, manufacturing machines, and the like. In large engineering machinery or engineering vehicles, due to the severe working environment and the action of heavy load, the fasteners on the large engineering machinery or engineering vehicles are impacted by vibration and load in all directions, so that the fasteners are easy to loosen, the functions of the fasteners are reduced or even fail, and great potential safety hazards are caused.

The fastener loosening prevention method commonly used at present generally comprises a non-detachable loosening prevention scheme and a friction-increasing loosening prevention scheme. The non-detachable anti-loosening scheme adopts manners of welding, bonding or punching point riveting and the like to change the detachable threaded connection into the non-detachable threaded connection. In the non-detachable anti-loosening scheme, the fastener cannot be reused, is troublesome to operate and is commonly used in important occasions requiring high anti-loosening performance and no need of disassembly. The anti-loosening scheme for increasing the friction force achieves the aim of anti-loosening by using a method for increasing the friction force between a thread or a bolt (screw) head and the end face of a nut or increasing the friction force between the thread and the screw head and the end face of the nut. The anti-loosening scheme for increasing the friction force is not limited by space, can be repeatedly disassembled, has poor reliability, and can reduce the anti-loosening effect due to vibration and the like after working for a certain time.

Disclosure of Invention

The technical problem solved by the invention is to provide the fastener, which enables the tightening piece to loosen more and recede through the matching action of the tightening piece and the annular piece, and the tightening piece cannot loosen because of tightening the locking force of the screw thread, so that the effect of inhibiting the tightening piece from further loosening and receding is achieved. And no matter what use state the tightening piece is in, the wrench device can be sleeved into the tightening piece and the annular piece at any angle within the range of the maximum loosening angle, and the tightening piece and the annular piece are screwed out simultaneously. And damage to the joint surface during disassembly and assembly is avoided. The structure of the invention can avoid screwing the tightening piece back to the original position during the disassembly, thereby simplifying the operation.

According to an embodiment of one aspect of the present invention, there is provided a fastener comprising: a tightening member configured to be combined with a mating screw to tighten a fastened member, the tightening member including a first body portion having a regular prism shape, a first end surface of the tightening member being provided with a first combining surface; and the annular piece, the annular piece with screw up the coaxial setting of piece and cooperation use, the annular piece includes: a second body part in a ring shape, wherein a second combining surface is arranged on one end surface of the second body part, and the first combining surface is combined with the second combining surface, so that the tightening piece is prevented from further loosening when the tightening piece is loosened; a flange portion protruding radially outward from an end portion of the second body portion opposite the second joining surface; and a plurality of first blocking protrusions disposed at intervals, the first blocking protrusions extending axially from the flange portion toward the second coupling surface on an outer side of the second main body portion, wherein an outer diameter of the first blocking protrusions is larger than an outer diameter of the tightening member; wherein the tightening member and the first blocking protrusion of the ring member are adapted to be coupled to a wrench device for synchronized disassembly and assembly of the tightening member and the ring member.

According to an exemplary embodiment of the present invention, the number of the first blocking protrusions corresponds to the number of sides of the regular prism.

According to an exemplary embodiment of the invention, the first coupling surface comprises at least two first coupling parts, the second coupling surface comprises at least two corresponding second coupling parts, the first coupling parts comprise a first inclined coupling surface and a second blocking surface extending in the circumferential direction, the second coupling parts comprise a first inclined coupling surface and a second blocking surface extending in the circumferential direction, wherein the first inclined coupling surface of the first coupling parts is configured to be in mating contact with the first inclined coupling surface of the second coupling parts, and the second blocking surface of the first coupling parts is configured to be in mating contact with the second blocking surface of the second coupling parts for enabling the coupling of the tightening element with the ring.

According to an exemplary embodiment of the present invention, the first blocking protrusions are positioned symmetrically with respect to a plane passing through the side edges of the regular prism in the radial direction, respectively, in the circumferential direction when the second blocking surface of the first coupling portion is in contact with the second blocking surface of the second coupling portion.

According to an exemplary embodiment of the present invention, wherein a central angle of a recess formed between two adjacent first blocking protrusions is larger than a central angle of the first blocking protrusions in a circumferential direction of the ring.

According to an exemplary embodiment of the present invention, wherein a central angle of a recess formed between two adjacent first blocking protrusions is twice as large as a central angle of the first blocking protrusions in a circumferential direction of the ring.

According to an exemplary embodiment of the present invention, the central angle of the first blocking protrusion is 20 ° in the circumferential direction of the ring.

According to an exemplary embodiment of the present invention, the tightening member includes:

an annular first projection extending coaxially and axially from the first body portion, the first engagement surface being formed on a surface of the first projection remote from the first body portion.

According to an exemplary embodiment of the present invention, the first protrusion and the second body part have the same outer diameter.

According to an exemplary embodiment of the present invention, the first inclined joint surface of the first joint portion and the first inclined joint surface of the second joint portion each form a screw surface having the same lead angle to be mutually engaged, the lead angle of the screw surface is larger than the lead angle of the engagement screw, and the direction of the screw rise of the screw surface on the second joint portion of the ring member is opposite to the screwing direction of the engagement screw.

According to an exemplary embodiment of the present invention, the second blocking surface of the first coupling portion and the second blocking surface of the second coupling portion have the same included angle with the horizontal plane, and are both obtuse angles or right angles.

According to an exemplary embodiment of the present invention, a side of the ring member contacting the fastened member is formed with a ratchet configured such that a friction force between the ring member and the fastened member is greater than a friction force between the tightening member and the ring member, so that the ring member is held stationary with respect to the fastened member and the screw when the tightening member is loosened with respect to the screw.

According to an exemplary embodiment of the invention, the ratchet teeth are configured to be arranged radially on a surface of the second side of the ring.

According to an exemplary embodiment of the present invention, the tightening member has a regular quadrangular prism shape or a regular hexagonal prism shape.

According to an exemplary embodiment of the present invention, the tightening member is a nut which is screw-engaged with the engagement screw.

According to an exemplary embodiment of the present invention, the tightening member includes: and a second protruding portion extending from one end of the first protruding portion, the second protruding portion being accommodated in the ring member.

According to an exemplary embodiment of the present invention, the second protrusion is formed to extend obliquely radially outward from the first protrusion;

the second projection cooperates with the inner bore of the ring such that the tightening member rotates relative to the ring but cannot be disengaged from the ring.

According to an exemplary embodiment of the invention, the inner bore of the ring comprises a first bore, a second bore having an inner diameter larger than the inner diameter of the first bore, and an inclined surface communicating the first bore and the second bore, wherein the first bore is located on a first side of the ring close to the tightening member, and the second bore is located on a second side of the ring remote from the tightening member; the inclined surface is configured to block the second protrusion.

According to an exemplary embodiment of the invention, the second projection is formed by a stamping process after passing through the ring from the first side of the ring to the second side.

According to an exemplary embodiment of the present invention, the nut and the ring member are separate members.

According to an exemplary embodiment of the present invention, the tightening member is a bolt head integrally connected with the mating screw and rotated together.

According to an embodiment of one aspect of the present invention, there is provided a wrench device for use with the fastener of any one of claims 1-21 to effect simultaneous disassembly and assembly of the tightening member and the ring member, wherein: the wrench device includes: a cylindrical third body portion;

a plurality of second blocking protrusions disposed at intervals, disposed inside the third body portion, and configured to contact-mate with the first blocking protrusions of the ring; and

a coupling portion provided inside the third main body portion and configured in a regular prism shape that matches a regular prism shape of the tightening member;

wherein the second blocking projection has an inner diameter that is greater than an outer diameter of the first body portion such that when the wrench device is coupled to the fastener, the second blocking projection is press fit against the corresponding first blocking projection to actuate the ring.

According to an exemplary embodiment of the present invention, in the fastening of the fastening member by the wrench device, the first and second coupling surfaces of the fastening member are tightly coupled to each other when one side of the second blocking protrusion is pressed against the corresponding side of the first blocking protrusion, so that the synchronous rotation of the tightening member and the ring member is achieved.

According to an exemplary embodiment of the present invention, wherein a central angle of a recess formed between two adjacent first blocking protrusions is larger than a central angle of the second blocking protrusion.

According to an exemplary embodiment of the present invention, a difference between a central angle of a recess formed between two adjacent first blocking protrusions and a central angle of the second blocking protrusion is not greater than a maximum allowable loosening angle of the tightening member with respect to the ring member.

According to an exemplary embodiment of the present invention, the number of the second blocking protrusions is the same as the number of the first blocking protrusions, such that the second blocking protrusions are inserted between the respective two adjacent first blocking protrusions when the wrench device is coupled to the fastener.

According to an exemplary embodiment of the present invention, a central angle of the second blocking protrusion in the circumferential direction of the third body portion is the same as a central angle of the first blocking protrusion in the circumferential direction of the ring-shaped member.

According to an exemplary embodiment of the present invention, the central angle of the second blocking protrusion in the circumferential direction of the third body portion and the central angle of the first blocking protrusion in the circumferential direction of the ring-shaped member are both 20 °.

According to an exemplary embodiment of the invention, the position of the second blocking projection in the circumferential direction of the third body part is offset by an angle in relation to a plane passing through the center point of the regular prism side of the joint in the radial direction towards the tightening direction of the fastener.

According to an exemplary embodiment of the present invention, the angle of deviation is 10 °.

According to an exemplary embodiment of the present invention, the wrench device further includes: and a connection part formed inside the third body part and configured to be connected with an external tool to screw the wrench device.

According to an exemplary embodiment of the present invention, a through hole extending in a radial direction of the third body part for insertion of a handle is formed in the connection part.

According to the fastener of the embodiments, through the combination of the joint surfaces with the lead angle larger than the lead angle of the threads of the matched screw, the fastener can inhibit the further loosening of the tightening piece when the tightening piece is loosened, so as to achieve the anti-loosening effect; and the wrench device can be combined to the fastener at any angle within the maximum allowable loosening angle, the tightening piece and the annular piece are simultaneously screwed or unscrewed, the tightening piece does not need to be screwed back to the original position, the operation is simplified, and the damage to the combining surface during the disassembly is avoided.

Drawings

The invention will be described in further detail with reference to the accompanying drawings, in which:

FIG. 1 is an exploded perspective view illustrating a fastener according to an exemplary embodiment of the present invention;

FIG. 2 is another exploded perspective view showing the fastener of FIG. 1;

FIG. 3 is a schematic perspective view showing the combination of the fasteners shown in FIG. 1;

FIG. 4 is a view showing the fastener shown in FIG. 1 schematic partial cross-sectional view before assembly;

FIG. 5 is a schematic view in partial cross-section showing the assembled fastener of FIG. 1;

FIG. 6 is a view showing the one shown in FIG. 5 a top view schematic of the fastener;

FIG. 7 is a schematic perspective view illustrating the ring of the fastener shown in FIG. 1;

FIG. 8 is a schematic view in partial cross-section showing the ring shown in FIG. 7;

FIG. 9 is a schematic top view illustrating the ring shown in FIG. 8;

FIG. 10 is a schematic partial cross-sectional view illustrating the fastener tightening member of the fastener shown in FIG. 1;

FIG. 11 is a schematic top view showing the tightening piece of the fastener shown in FIG. 10;

FIG. 12 is a geometric schematic showing the helix angle of the first engagement surface of the tightening piece shown in FIG. 1;

FIG. 13 is a geometric schematic showing the lead angle of the external thread of the screw in cooperation with the tightening piece of the embodiment of the present invention;

FIG. 14 is a schematic perspective view showing a wrench device for removing the fastener;

FIG. 15 is a schematic cross-sectional view illustrating the wrench device shown in FIG. 14;

FIG. 16 is a right side schematic view illustrating the wrench device shown in FIG. 15;

fig. 17 is a left side schematic view showing the wrench device shown in fig. 17. And

Fig. 18 is an exploded view illustrating a fastener according to another exemplary embodiment of the present invention.

Detailed Description

The technical scheme of the invention is further specifically described below through examples and with reference to the accompanying drawings. In the specification, the same or similar reference numerals denote the same or similar components. The following description of embodiments of the present invention with reference to the accompanying drawings is intended to illustrate the general inventive concept and should not be taken as limiting the invention.

Furthermore, in the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present disclosure. It may be evident, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are shown in the drawings in order to simplify the drawings.

According to the present general inventive concept, there is provided a fastener comprising: a tightening member configured to be combined with a mating screw to tighten a fastened member, the tightening member including a first body portion having a regular prism shape, a first end surface of the tightening member being provided with a first combining surface; and the annular piece, the annular piece with screw up the coaxial setting of piece and cooperation use, the annular piece includes: a second body part in a ring shape, wherein a second combining surface is arranged on one end surface of the second body part, and the first combining surface is combined with the second combining surface, so that the tightening piece is prevented from further loosening when the tightening piece is loosened; a flange portion protruding radially outward from an end portion of the second body portion opposite the second joining surface; and a plurality of first blocking protrusions disposed at intervals, the first blocking protrusions extending axially from the flange portion toward the second coupling surface at an outer side of the second body portion, wherein an outer diameter of the first blocking protrusions is larger than an outer diameter of the tightening member. The first blocking protrusions of the tightening piece and the annular piece are suitable for being combined with a matched wrench device, so that the tightening piece and the annular piece can be synchronously disassembled and assembled.

According to one exemplary embodiment, the fastener of the present disclosure may be used in a work machine, for example as a connection for track shoes, chassis parts in construction vehicles. Because of the harsh operating conditions of the work machine, there is a large vibration and a large load during use, particularly lateral loads, which cause loosening of the fastener over time.

Those skilled in the art will appreciate that the ring may be made to have a greater friction with the fastened member by taking various measures, and that the friction between the ring and the fastened member is greater than the friction between the tightening member and the ring. Thus, under a certain external force, the ring member remains stationary when the tightening member is loosened with respect to the fastened member.

According to one embodiment of the invention, the tightening member has a regular quadrangular prism shape, a regular hexagonal prism shape or other regular prismatic shape. As shown in fig. 1-11, the tightening member is a nut 1 that is threadedly engaged with the screw 100 (fig. 13). The nut 1 may be a common nut such as a square nut or a hexagonal nut. In another embodiment, as shown in fig. 18, the tightening member is a bolt head 200, and the bolt head 200 is integrally connected to and rotates together with a mating screw 201. Thus, the bolt head 200 and the shank 201 constitute one bolt. The bolt head 200 may be a tetragonal bolt head, a hexagonal bolt head, or other common bolt head shape.

Referring now to fig. 1-17, a fastener of an embodiment of the present invention will be described using a tightening member as an example of a nut.

According to an exemplary embodiment of the present invention, the fastener includes: a tightening member 1 configured as a nut configured to be combined with a mating screw 100 to tighten a fastened member (not shown), the tightening member including, as shown in fig. 2, a first body portion 11 in the shape of a regular prism, a first joining surface (an upper end surface of the nut in fig. 2) being provided on a first end surface thereof; and a ring member 2, the ring member 2 and the tightening member 1 are coaxially arranged and matched for use, and the ring member 2 comprises: an annular second body portion 22 provided with a second engaging surface (an upper end surface of the annular member 2 in fig. 1) on one end surface thereof, the first engaging surface being engaged with the second engaging surface so as to hinder further loosening of the tightening member when the tightening member is loosened; a flange portion 21, the flange portion 21 protruding radially outward from an end portion of the second body portion 22 opposite to the second joint surface; and a plurality of first blocking projections 23 disposed at intervals, the first blocking projections extending axially from the flange portion toward the second joining surface on the outer side of the second main body portion, wherein an outer diameter of the first blocking projections is larger than an outer diameter of the tightening member; wherein said tightening member and said first blocking projection of said ring-shaped member 2 are adapted to cooperate with a cooperating wrench device 3 (shown in fig. 14-17) to achieve a synchronized dismounting of said tightening member and said ring-shaped member.

The wrench device 3 can realize synchronous screwing of the screwing piece 1 and the annular piece 2 during fastener installation, and can also be used for realizing synchronous disassembly of the screwing piece 1 and the annular piece 2 during fastener disassembly without damaging the joint surface between the screwing piece 1 and the annular piece 2. The specific manner of operation will be described hereinafter.

According to an exemplary embodiment of the present invention, the first blocking protrusions include at least two first blocking protrusions 23, and the at least two first blocking protrusions 23 are uniformly distributed along a circumferential direction of a radially outer side surface of the second body part 22. According to an exemplary embodiment of the present invention, the number of the first blocking protrusions 23 corresponds to the number of sides of the regular prism. For example, when the nut runner 1 is a square nut, the number of first blocking protrusions may be set to 4, and when the nut runner 1 is a square nut, the number of first blocking protrusions may be set to 6.

According to an exemplary embodiment of the invention, as shown in fig. 1 and 2, the first bonding surface comprises at least two first bonding portions, the second bonding surface comprises at least two corresponding second bonding portions, the first bonding portions comprise first inclined bonding surfaces 121 and second blocking surfaces 122 extending in the circumferential direction, the second bonding portions comprise first inclined bonding surfaces 221 and second blocking surfaces 222 extending in the circumferential direction, wherein the first inclined bonding surfaces 121 of the first bonding portions are configured to be in cooperative contact with the first inclined bonding surfaces 221 of the second bonding portions, and the second blocking surfaces 122 of the first bonding portions are configured to be in cooperative contact with the second blocking surfaces 222 of the second bonding portions so as to realize bonding of the nut and the ring.

Fig. 12 is a geometric schematic diagram showing the lead angle of the first bonding surface of the nut. Fig. 13 is a geometric schematic showing the lead angle of the external thread of the screw rod mated with the nut of the embodiment of the present invention. According to an exemplary embodiment of the present invention, the first inclined bonding surface 121 of the first bonding surface and the first inclined bonding surface 221 of the second bonding surface each form spiral surfaces having the same lead angle to be matched with each other. In fig. 12, the right part of fig. 12 shows a schematic view of the developed dimensional relationship of the helicoids. Phi is the helix angle of the first inclined joining surfaces 121 and 221. Ph is the climbing height of the spiral surface, and D is the pitch diameter of the spiral surface. In fig. 13, a is a lead angle of an external thread of the screw 100 to be engaged with the nut of the embodiment of the present invention, d is the major diameter of the screw thread, d1 is the minor diameter of the screw thread, and d2 is the median diameter of the screw thread. Since the nut 1 is engaged with the screw, the lead angle of the internal thread of the nut 1 is also α.

According to an exemplary embodiment of the present invention, as shown in fig. 1 and 2, the first inclined joint surface 121 of the first joint and the first inclined joint surface 221 of the second joint each form spiral surfaces having the same lead angle to be matched with each other. The helix angle phi of the helical surface is larger than the thread angle alpha of the screw rod, and the direction of helix rising of the helical surface on the second combination part of the annular piece 2 is opposite to the screwing direction of the screw rod, namely the screwing direction of the internal thread of the nut. Thus, in the case where the ring member 2 is stationary with respect to the screw 100 and the nut 1 is rotated by a certain angle with respect to the screw 100 in a direction opposite to the screw thread direction of the screw, the climbing height of the outside of the nut 1 with respect to the ring member 2 in the axial direction (upward direction in fig. 1) is larger than the loosening height of the inside of the nut with respect to the screw thread in the axial direction (upward direction in fig. 1), since the screw, the ring member and the fastened member are stationary, the nut 1 stretches the engaged screw, that is, the nut further compresses the ring member, so that the ring member further compresses the fastened member. The ring thus has the function of a lock washer.

Those skilled in the art will also appreciate that the thread angle of the internal thread of the nut connector will be correspondingly adjusted for different thread angles of the fastener.

According to an exemplary embodiment of the present invention, as shown in fig. 3, the first blocking protrusion 23 is positioned such that the first blocking protrusion 23 is symmetrical in the circumferential direction with respect to a plane passing through the side edges of the regular prism in the radial direction when the second blocking surface 122 of the first coupling portion is in contact with the second blocking surface 222 of the second coupling portion.

According to an exemplary embodiment of the present invention, as shown in fig. 1 to 4, 9, in the circumferential direction of the ring-shaped member 2, the central angle β of the recess 24 formed between two adjacent first blocking protrusions 23 is larger than the central angle γ of the first blocking protrusions 23.

According to an exemplary embodiment of the present invention, the central angle β of the recess 24 formed between two adjacent first blocking protrusions 23 is twice the central angle γ of the first blocking protrusions 23 in the circumferential direction of the ring-shaped member 2.

According to an exemplary embodiment of the invention, the central angle γ of the first blocking projection 23 is 20 ° in the circumferential direction of the ring element 2.

According to an exemplary embodiment of the present invention, the tightening member includes an annular first protruding portion 12 extending coaxially and axially from the first body portion 11, and the first engaging surface is formed on a surface of the first protruding portion 12 remote from the first body portion 11, as shown in fig. 2. According to an exemplary embodiment of the present invention, the first projection 12 and the second body portion 22 have the same outer diameter.

According to an exemplary embodiment of the invention, in order that said second blocking surfaces 122, 222 abut to achieve mutual positioning of the nut and the ring 2 when the nut is in mounting engagement with the ring 2, and to prevent rotation of the nut 1 relative to the ring 2 in the same direction as the screwing direction of the threads of the mating screw, said second blocking surfaces 122, 222 are at the same angle to the horizontal and are each arranged at an obtuse or right angle.

According to an exemplary embodiment of the present invention, as shown in fig. 2, a ratchet 212 is formed on a surface of the ring 2 on a side close to the fastened element, and the ratchet 212 is configured such that a friction force between the ring 2 and the fastened member is greater than a friction force between the nut 1 and the ring 2, so that the ring 2 is held stationary with respect to the fastened member and the screw when the nut 1 is loosened with respect to the screw.

According to an exemplary embodiment of the present invention, the ratchet teeth 212 are configured to be radially arranged on the surface of the ring on the side near the fastened member as shown in fig. 2. The number of the radial ratchets is larger than that of the first combining parts and the matched second combining parts, and the closely arranged radial ratchets generate larger friction force between the annular piece 2 and the fastened piece, and the friction force is larger than that between the nut 1 and the annular piece 2, so that the annular piece 2 is kept motionless relative to the fastened piece when the nut loosens.

According to an exemplary embodiment of the present invention, the tightening member includes a second protruding portion 13, the second protruding portion 13 extending from one end of the first protruding portion 12, the second protruding portion 13 being accommodated in the ring member as shown in fig. 5.

According to an exemplary embodiment of the invention, the nut 1 and the ring 2 are configured such that they are not completely separable.

According to an exemplary embodiment of the invention, the second projection 13 extends obliquely radially outwards from the first projection. The second projection 13 cooperates with the inner bore of the ring such that the tightening member rotates relative to the ring but cannot be disengaged from the ring 2.

According to an exemplary embodiment of the invention, the inner bore of the ring comprises a first bore 201, a second bore 202 having an inner diameter larger than the inner diameter of the first bore, and an inclined surface 203 communicating the first bore and the second bore, wherein the first bore is located on a first side of the ring close to the tightening member, and the second bore is located on a second side of the ring remote from the tightening member; the inclined surface is configured to block the second protruding portion 13. As shown in fig. 5, the second projection 13 cooperates with the inclined surface 203 so that the tightening member rotates relative to the ring member but cannot be disengaged from the ring member. The second projection 13 has an outer diameter larger than the inner diameter of the first hole 201 of the ring 2 shown in fig. 5. In this way, the second projection 13 abuts against the inclined surface 203 as shown in fig. 5, so that the nut rotates relative to the ring but cannot be disengaged from the ring. In one embodiment, by providing that the height of the gap between the second projection 13 in the axial direction and the inclined surface 203 formed in the ring member 2 is smaller than the heights of the first and second blocking surfaces in the axial direction, the nut 1 can be rotated with respect to the ring member 2 only by a predetermined angle range, which can be set as the maximum allowable loosening angle of the fastener, i.e., the maximum allowable loosening angle of the fastener with respect to the tightening member, so as to limit the distance by which the mating screw is stretched by the nut 1 in the axial direction, for example, less than 1.0mm, thereby protecting the fastener from damage. The maximum allowable loosening angle may correspond to, for example, a strength limit of the mating screw. Specifically, in the fastener according to the embodiment of the present invention, since the first inclined bonding surface 121 of the first bonding portion is configured to be in mating contact with the first inclined bonding surface 221 of the second bonding portion, the second blocking surface 122 of the first bonding portion is configured to be in mating contact with the second blocking surface 222 of the second bonding portion. In this way, the nut 1 will gradually move away from the ring 2 as the nut 1 is turned away from the blocking surface relative to the ring 2, but the nut 1 can only be rotated relative to the ring 2 by a predetermined angular range due to the restriction of the second projection 13 and the inclined surface 203 of the ring 2. In one embodiment, the maximum angle of rotation of the nut relative to the ring is in the range of 30-70 degrees, preferably 40-70 degrees.

According to an exemplary embodiment of the invention, the second protrusion 13 is formed by a stamping process after the first protrusion 13 passes through the ring from the first side to the second side of the ring.

According to an exemplary embodiment, the nut 1 and the ring 2 may also be separate pieces, which are only temporarily engaged during use.

The following describes the anti-loosening action of a nut fastener according to an embodiment of the present invention with reference to fig. 1-13.

When the fastener of the embodiment of the present invention is applied to, for example, an engineering vehicle for fastening a fastened member, the nut 1 and the ring-shaped member 2 are aligned, i.e. such that the second blocking surface 122 of the first coupling portion cooperates with the second blocking surface 222 of the second coupling portion to prevent rotation of the nut relative to the ring in the same direction as the screwing direction of the mating screw. The fastener 1 is integrally screwed to the fastened member in the same direction as the screwing direction of the mating screw, and the fastened member is clamped and fastened by applying a pre-tightening force.

Loosening and backing of the nut 1 occurs with the lapse of time of use. Since the friction between the ring 2 and the fastened part is greater than the friction between the nut and the ring, the ring 2 remains stationary relative to the screw and the fastened part during the initial movement of the nut 1 relative to the ring 2. The preliminary movement is along a first incline of the first joint of the mating contact the bonding surface 121 is formed with a first inclined bonding surface 221 of the second bonding portion. As shown in fig. 12 and 13, since the first inclined joint surface 121 and the first inclined joint surface 221 are formed as a spiral surface, the spiral angle of the spiral surface is greater than the thread angle of the screw. Then, when the nut is loosened, in the case of a certain angle of loosening rotation, since the first protrusion portion and the body portion of the nut are moved in the direction of the helix angle along the first inclined coupling surfaces 121 and 221, the climbing height of the outside of the nut is greater than the height of the inside thread of the nut withdrawn from the external thread of the matched screw 100, thereby forming a stretch for the matched screw. Thus, a greater locking force is formed at the mating connection of the internal thread of the nut and the external thread of the mating screw, which locking force inhibits further loosening of the nut 1. And the cooperating screw produces an opposite pulling force on the nut 1 towards the ring element 2, so that the nut 1 is pressed down against said ring element 2, the ring element 2 further compressing the fastened element, whereby the friction between the ring element 2 and the fastened element is greater, inhibiting the movement of the fastening element. Thus, the loosening of the nut is performed, the larger the tension of the screw rod is caused by the difference of the helix angle and the thread helix angle, and the larger the locking force is, so that the nut is less prone to loosening.

According to an exemplary embodiment of an aspect of the present invention, as shown in fig. 14 to 17, there is provided a wrench device 3 for the above-mentioned fastener, for achieving synchronous disassembly of the tightening member and the ring member, wherein: the wrench device includes: a tubular third body portion 31; a plurality of second blocking protrusions 320 disposed at intervals inside the third body part and configured to contact-mate with the first blocking protrusions of the ring; and a coupling portion 33 provided inside the third main body portion and configured in a regular prism shape that matches the regular prism shape of the tightening piece; wherein the second blocking protrusion has an inner diameter that is larger than an outer diameter of the second body portion of the fastener such that when the wrench device is coupled to the fastener, the second blocking protrusion is press fit against the corresponding first blocking protrusion to actuate the ring.

In one embodiment, when one side of the second blocking protrusion 320 is pressed against the corresponding side of the first blocking protrusion 23 during the fastening of the fastening member by the wrench device, the first and second coupling surfaces of the fastening member are tightly coupled to each other, and at this time, the first and second inclined coupling surfaces 121 and 221 of the first and second coupling parts are contacted to each other, and the second blocking surface 122 of the first and second coupling parts are contacted to each other, so that the synchronous rotation of the tightening member and the ring member is achieved. Thus, the combination part applies a tightening force to the nut, the second blocking protrusion applies an actuating force to the first blocking protrusion, and the two are screwed together, so that the two are prevented from being screwed together only through the pressing contact of the first blocking surface and the second blocking surface in the fastening process, and the damage to the first blocking surface and the second blocking surface is avoided. And the tightening member and the ring member can be made to be in an optimal coupled state when the fastener is in a fastened state, i.e., the tightening member is not loosened with respect to the ring member.

According to an exemplary embodiment of the present invention, the central angle β of the recess 24 formed between two adjacent first blocking protrusions 23 is larger than the central angle of the second blocking protrusion 320. At the same time, the central angle β of the recess 24 is made larger than the central angle of the second blocking projection 320, so that if the second blocking projection 320 abuts against the upper side of the first blocking projection 23 in the axial direction of the fastener during the coupling of the wrench device to the fastener, the wrench device is rotated in the tightening direction, i.e., the returning direction of the fastener 1, without having to return completely to the initial position when the fastener 1 is not loosened, thus simplifying the operation and avoiding damage to the first coupling surface and the second coupling surface due to the presence of a large locking force during the returning.

According to an exemplary embodiment of the present invention, the difference between the central angle β of the recess 24 formed between two adjacent first blocking protrusions and the central angle of the second blocking protrusion 320 is not greater than the maximum allowable loosening angle of the tightening member with respect to the ring member. I.e. the difference is smaller than the maximum allowable loosening angle set in order not to damage the joint surface between the tightening element 1 and the ring element 2 and not to exceed the stretching allowable limit of the mating screw, which is for example 60 °. So that the maximum angle by which the wrench device rotates the tightening element 1 relative to the ring element 2 during the removal process is smaller than the maximum allowed loosening angle, so that no damage to the joint surface occurs due to the handling during the removal process. Taking the hexagonal nut shown in fig. 1-3 as an example, according to an exemplary embodiment, the central angle of the second blocking protrusion 320 in the circumferential direction of the third body portion and the central angle of the first blocking protrusion 23 in the circumferential direction of the ring member are both 20 °. And according to an exemplary embodiment, the central angle of the recess 24 between the two first blocking projections 23 is 40 deg. for receiving said second blocking projection 320. And since the central angle of the second blocking protrusion 320 is 20 deg., the maximum angle of rotation of the second blocking protrusion 320 in the recess 24 with respect to the ring 2 is 40 deg. -20 deg., i.e. 20 deg..

According to an exemplary embodiment of the present invention, the number of the second blocking protrusions 320 is the same as the number of the first blocking protrusions 23, so that the second blocking protrusions 320 are inserted between the corresponding two adjacent first blocking protrusions 23 when the wrench device is coupled to the fastener.

According to an exemplary embodiment of the present invention, as shown in fig. 1, 14 and 17, the central angle of the second blocking protrusion in the circumferential direction of the third body part is the same as the central angle of the first blocking protrusion in the circumferential direction of the ring-shaped member.

According to an exemplary embodiment of the invention, for a hexagonal nut, the central angle of the second blocking protrusion 320 in the circumferential direction of the third body portion and the central angle of the first blocking protrusion 23 in the circumferential direction of the ring-shaped member are both 20 °.

According to an exemplary embodiment of the present invention, as shown in fig. 17, in the circumferential direction of the third body portion, the position of the second blocking protrusion (320) is deviated at an angle toward the tightening direction of the fastener with respect to a plane passing through the center point of the regular prism side of the coupling portion in the radial direction.

According to an exemplary embodiment of the invention, said angle of deviation is 10 °.

According to an exemplary embodiment of the present invention, the wrench device further comprises: a connection portion 34 formed inside the third body portion 31 and configured to be connected with an external tool to screw the wrench device.

According to an exemplary embodiment of the present invention, as shown in fig. 15, the connection part is formed at the inner side of the third body part 31 and is configured to be connected with an external tool to screw the wrench device.

According to an exemplary embodiment of the present invention, as shown in fig. 15, a through hole extending in a radial direction of the third body part for insertion of a handle is formed in the connection part.

According to an exemplary embodiment of the present invention, as shown in fig. 15 to 17, the coupling portion is formed in a hexagonal shape.

According to an exemplary embodiment of the present invention, as shown in fig. 15 to 17, the connection part is formed in a quadrangular shape.

The operation of tightening and removing the fastener using the wrench device 3 is specifically described below:

when screwing, the ring-shaped member 2 is first sleeved, and the wrench device 3 is used to enable the joint part 33 of the ring-shaped member 2 to be matched with the outer side face of the regular prism of the screwing member 1, so that the screwing member 1 is screwed in until the second blocking surface 122 of the first joint part of the screwing member 1 abuts against the second blocking surface 222 of the second joint part of the ring-shaped member 2. At this time, according to an exemplary embodiment, as shown in fig. 3, for example, when the second blocking protrusion 320 and the first blocking protrusion have central angles of 20 ° with respect to the hexagonal nut, and the first blocking protrusion 23 is symmetrical in the circumferential direction with respect to the radial plane in which the corresponding regular prism side edges lie, that is, the first blocking protrusion 23 has both sides angles of 10 ° with respect to the radial plane in which the side edges lie, the second blocking surface 122 of the first joining portion of the tightening member 1 abuts against the second blocking surface 222 of the second joining portion of the ring member 2, and the side surface of the second blocking protrusion 320 located downstream in the tightening direction with respect to the radial plane in which the center point of the regular prism side of the joining portion 33 lies is deviated by 10 ° with respect to the side surface of the first blocking protrusion 23, which is shown in dotted line form in fig. 6, whereby the angle in which the second blocking protrusion 320 deviates from the radial plane in the center point of the regular prism side edge lies is 10 °, further tightening of the ring member 1 is achieved by the tightening device for the tightening of the ring member 2, and further tightening of the ring member 1 is achieved by the tightening device.

At the beginning of the disassembly, the second blocking surface 122 of the nut is distanced from the second blocking surface 222 of the second joint of the ring 2, due to the loosening of the nut during use, the nut having a relative movement with respect to the ring 2 along the first inclined joint surfaces 221, 121. At this time, the wrench device 3 is sleeved such that the coupling portion 33 of the wrench device 3 is coupled with the outer side surface of the regular prism-shaped tightening member, the wrench device 3 moves toward the fastener, and if the second blocking protrusion 320 of the wrench device 3 is not blocked by the first blocking protrusion 23 of the ring-shaped member, the second blocking protrusion 320 is interposed between the corresponding two adjacent first blocking protrusions 23; if the second blocking protrusions are blocked by the first blocking protrusions, the wrench device 3 is rotated in the same direction as the screwing direction of the mating screw, so that the nut is moved in the opposite direction to the unscrewing direction until the second blocking protrusions 320 of the second blocking protrusions of the wrench device 3 are brought between the respective two adjacent first blocking protrusions 23, after which the wrench device 3 is rotated in the disassembly direction until the second blocking protrusions 320 are pressed against the respective first blocking protrusions 23 located downstream in the disassembly direction, and the ring 2 and the nut are screwed with further rotation of the wrench device 3, synchronously disassembling the nut 1 and the ring 2. As an example, according to an exemplary embodiment of the present invention, for a hexagonal nut, since the angle of the recess 24 between the two first blocking protrusions 23 on the ring member in the circumferential direction of the ring member is 40 ° and the angle of the second blocking protrusion 320 in the circumferential direction is 20 °, the maximum rotation angle of the second blocking protrusion 320 in the circumferential direction in the recess before pressing against the first blocking protrusion 23 located downstream in the disassembly direction is 20 °, i.e., the maximum angle at which the wrench device rotates the tightening member 1 relative to the ring member 2 is 20 °, which is smaller than the maximum allowable loosening angle set so as not to damage the joint surface between the tightening member 1 and the ring member 2 and not to exceed the tensile allowable limit of the mating screw.

It will be appreciated by those skilled in the art that the above-described hexagonal nuts are used as examples, which are not limiting, and the number of regular prism sides of the nut, the number of first and second blocking protrusions, the central angles of the first and second blocking protrusions, and the central angle of the recess, respectively, may be specifically set as desired according to different nut types and different application needs. For example, the position of the first blocking protrusion 23 on the outer side surface of the second body portion may be different from the illustrated embodiment, and any position in the circumferential direction of the outer side surface may be provided, and the number thereof does not need to correspond to the number of sides of the regular prism. The central angle of the first blocking projection 23 and the central angle of the recess 24 can also be varied, and smaller or larger central angles of the first blocking projection 22 can be provided, as long as tightening of the fastening member and removal of the fastening member can be achieved without damaging the joint surface and the fastening member. It is also reasonable that the second blocking protrusion 320 may or may not be offset with respect to the radial plane in which the center point of the edge of the positive edge is located, as long as it is possible to achieve a synchronous rotation of the tightening member and the ring member when the first blocking surface and the second blocking surface are in contact with each other during tightening of the fastener by the wrench device.

In this process, an external tool may be used to insert the connecting portion 34, thereby tightening or removing the fastener by an external tool via the wrench device.

With the wrench device, no matter what use state the nut is in, within the range of the maximum loosening angle, the wrench device can be sleeved into the nut and the ring-shaped piece at any angle, and the nut and the ring-shaped piece are screwed out simultaneously. And damage to the joint surface during disassembly and assembly is avoided. The structure of the invention can avoid screwing the tightening piece back to the original position during the disassembly, thereby simplifying the operation. Meanwhile, damage to the joint surface during disassembly and assembly is avoided. And the wrench device can be used for realizing the installation pre-tightening of the fastener and the disassembly of the fastener.

FIG. 18 is a diagram illustrating another example according to the present invention an exploded view of the fastener of the exemplary embodiment. The fastener 20 shown in fig. 18 differs from the fastener 10 shown in fig. 1-11 in that, in the fastener 20 shown in fig. 18, the tightening member is a bolt head 200 integrally connected with the screw 201 and rotated together with the screw 201.

Referring to fig. 18, the fastener 20 includes a bolt including a bolt head 200 and a shank 201 having a threaded portion, which are integrally connected and rotated together, and a ring member 2. A first joint surface is formed on a first end surface (lower surface in fig. 18) of the bolt head. The ring 2 is arranged coaxially with the bolt head and the threaded rod 201 passes through the through hole of the ring. The first engagement surface engages the second engagement surface such that further loosening of the bolt head 200 is resisted when the bolt head 200 is loosened.

In the fastener 20, the structure and the combination of the ring-shaped member, the first combination surface of the bolt head and the second combination surface of the ring-shaped member are the same as those of the fastener shown in fig. 1 to 11, and will not be described again.

The wrench device described above is equally applicable to the installation and removal of the fastener 20, and the installation and removal process of the fastener 20 is the same as the installation and removal process of the fastener 10, and will not be described again.

According to the fastener disclosed by the various embodiments of the invention, through the matching action of the tightening piece and the annular piece, the tightening piece is loosened and retreated, the tightening force of the thread is tightened, and the tightening piece cannot be loosened, so that the effect of inhibiting the tightening piece from further loosening and retreating is achieved. And no matter what use state the nut is in, the wrench device can be sleeved into the nut and the ring-shaped piece at any angle within the range of the maximum loosening angle, and the nut and the ring-shaped piece are simultaneously screwed out. And damage to the joint surface during disassembly and assembly is avoided. The structure of the invention can avoid screwing the tightening piece back to the original position during the disassembly, thereby simplifying the operation. Meanwhile, damage to the joint surface during disassembly and assembly is avoided.

Those skilled in the art will appreciate that the embodiments described above are exemplary and that modifications may be made by those skilled in the art, and that the structures described in the various embodiments may be freely combined without conflict in terms of structure or principle.

Having described the preferred embodiments of the present invention in detail, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the scope and spirit of the following claims and that the invention is not limited to the implementations of the exemplary embodiments set forth in the specification.

Claims

1. A fastener, comprising:

a tightening member (1) configured to be combined with a mating screw to tighten a fastened member, the tightening member including a first body portion (11) of a regular prism shape, a first combining surface being provided on a first end surface of the tightening member; and

the annular piece (2), the annular piece with screw up the coaxial setting of piece and cooperation use, the annular piece includes:

an annular second main body portion (22) provided with a second joining surface on one end surface thereof, the first joining surface being joined with the second joining surface so as to hinder further loosening of the tightening member when the tightening member is loosened;

A flange portion (21) protruding radially outward from an end portion of the second main body portion (22) opposite to the second joint surface; and

a plurality of first blocking projections (23) disposed at intervals, the first blocking projections extending axially from the flange portion toward the second joining surface on the outer side of the second main body portion, wherein an outer diameter of the first blocking projections is larger than an outer diameter of the tightening member;

wherein the tightening member and the first blocking protrusion of the ring member are adapted to be coupled to a wrench device to achieve synchronized disassembly and assembly of the tightening member and the ring member,

wherein the first bonding surface includes at least two first bonding portions, the second bonding surface includes at least two corresponding second bonding portions, and the first blocking protrusions are positioned so as to be symmetrical in the circumferential direction with respect to a plane passing through the side edges of the regular prism in the radial direction, respectively, when the second blocking surfaces of the first bonding portions are in contact with the second blocking surfaces of the second bonding portions.

2. The fastener of claim 1, wherein,

the number of the first blocking protrusions corresponds to the number of sides of the regular prism.

3. The fastener of claim 2, wherein the first engagement portion includes a first angled engagement surface and a second blocking surface extending in a circumferential direction, the second engagement portion includes a first angled engagement surface and a second blocking surface extending in a circumferential direction, wherein the first angled engagement surface of the first engagement portion is configured to matingly contact the first angled engagement surface of the second engagement portion, and the second blocking surface of the first engagement portion is configured to matingly contact the second blocking surface of the second engagement portion to effect engagement of the tightening member with the ring.

4. The fastener according to claim 1, wherein a central angle of a recess (24) formed between two adjacent first blocking projections is larger than a central angle of the first blocking projections in a circumferential direction of the ring.

5. The fastener according to claim 4, wherein a central angle of a recess formed between two adjacent first blocking protrusions is twice as large as a central angle of the first blocking protrusions in a circumferential direction of the ring.

6. The fastener according to claim 5, wherein a central angle of the first blocking protrusion is 20 ° in a circumferential direction of the ring.

7. The fastener of claim 1, wherein the tightening member comprises:

an annular first projecting portion (12) extending coaxially and axially from the first main body portion (11), the first engaging surface being formed on a surface of the first projecting portion (12) remote from the first main body portion.

8. The fastener of claim 7, wherein the first projection (12) and the second body portion (22) have the same outer diameter.

9. A fastener according to claim 3, wherein the first inclined joining surface of the first joining portion and the first inclined joining surface of the second joining portion each form a helicoidal surface having the same lead angle for mutual engagement, the lead angle of the helicoidal surface being larger than the lead angle of the mating screw, and the direction of the rise of the helicoidal surface on the second joining portion of the ring member is opposite to the screwing direction of the mating screw.

10. A fastener according to claim 3, wherein the second blocking surface of the first junction and the second blocking surface of the second junction are at the same angle to the horizontal and are both obtuse or right angles.

11. The fastener according to claim 1, wherein a side of the ring member in contact with the fastened member is formed with a ratchet configured such that a friction force between the ring member and the fastened member is greater than a friction force between the tightening member and the ring member, so that the ring member is held stationary with respect to the fastened member and the screw when the tightening member is loosened with respect to the screw.

12. The fastener of claim 11, wherein the ratchet teeth are configured to be radially aligned on a surface of the second side of the ring.

13. The fastener of claim 1, wherein the tightening member has a regular quadrangular prism shape or a regular hexagonal prism shape.

14. The fastener of any one of claims 1-13, wherein the tightening member is a nut that is threadedly engaged with the engagement screw.

15. The fastener of claim 7, wherein the tightening member comprises:

-a second projection (13), the second projection (13) extending from one end of the first projection (12), the second projection being accommodated in the ring.

16. The fastener according to claim 15, wherein the second projection (13) extends obliquely radially outwardly from the first projection (12);

the second projection (13) cooperates with the inner bore of the ring such that the tightening member rotates relative to the ring but cannot be disengaged from the ring (2).

17. The fastener of claim 16, wherein the inner bore of the ring comprises a first bore (201) located on a first side of the ring proximate the tightening member, a second bore (202) having an inner diameter greater than the inner diameter of the first bore, and an inclined surface communicating the first bore and the second bore, the second bore being located on a second side of the ring distal from the tightening member; the inclined surface is configured to be capable of blocking the second protruding portion (13).

18. The fastener of claim 17, wherein the second projection is formed by a stamping process from a first side of the loop through the loop to the second side.

19. The fastener of claim 14, wherein the nut and the ring are separate pieces.

20. The fastener of any one of claims 1-13, wherein the tightening member is a bolt head integrally connected with and rotatable with the mating screw.

21. A wrench apparatus for use with the fastener of any one of claims 1-20 to effect simultaneous disassembly and assembly of the tightening member and the ring member, wherein:

the wrench device includes:

a tubular third body (31);

a plurality of second blocking protrusions (320) disposed at intervals inside the third body portion and configured to contact-mate with the first blocking protrusions of the ring; and

a coupling portion (33) provided inside the third main body portion and configured in a regular prism shape that matches the regular prism shape of the tightening member;

wherein the second blocking projections have an inner diameter that is larger than an outer diameter of the first body portion (22) such that when the wrench device is coupled to the fastener, the second blocking projections press fit against the corresponding first blocking projections to actuate the ring.

22. The wrench device of claim 21, wherein the first and second engagement surfaces of the fastener are tightly engaged with each other when one side of the second blocking protrusion is pressed against the corresponding side of the first blocking protrusion during tightening of the fastener by the wrench device to achieve synchronous rotation of the tightening member and the ring member.

23. Wrench device according to claim 21 or 22, wherein the central angle of a recess (24) formed between two adjacent first blocking protrusions is larger than the central angle of the second blocking protrusion (320).

24. The wrench device according to claim 23, wherein a difference between a central angle of a recess (24) formed between two adjacent first blocking protrusions and a central angle of the second blocking protrusion (320) is not greater than a maximum allowable loosening angle of the tightening member with respect to the ring member.

25. The wrench device according to claim 24, wherein the number of second blocking protrusions is the same as the number of first blocking protrusions (23), such that when the wrench device is coupled to the fastener, the second blocking protrusions (320) are interposed between respective two adjacent first blocking protrusions (23).

26. The wrench device of any one of claims 21-22 and 24-25 wherein a central angle of the second blocking protrusion in a circumferential direction of the third body portion is the same as a central angle of the first blocking protrusion in a circumferential direction of the ring.

27. The wrench device according to claim 23, wherein a central angle of the second blocking protrusion in a circumferential direction of the third body portion is the same as a central angle of the first blocking protrusion in a circumferential direction of the ring.

28. The wrench device according to claim 26, wherein a central angle of the second blocking protrusion in a circumferential direction of the third body portion and a central angle of the first blocking protrusion in a circumferential direction of the ring member are each 20 °.

29. The wrench device according to any one of claims 21-22 and 24-25, wherein the second blocking protrusion (320) is located at an angle with respect to a plane passing through a center point of a regular prism side of the joint in a radial direction in a circumferential direction of the third body portion, towards a tightening direction of the fastener.

30. The wrench device according to claim 23, wherein in the circumferential direction of the third body portion, the position of the second blocking protrusion (320) is offset at an angle to the tightening direction of the fastener with respect to a plane passing through the center point of the regular prism side of the coupling portion in the radial direction.

31. The wrench device of claim 29 wherein the angle of departure is 10 °.

32. The wrench device of claim 21, further comprising:

and a connecting portion (34) formed inside the third body portion (31) and configured to be connected with an external tool to screw the wrench device.

33. The wrench device according to claim 32, wherein a through hole extending in a radial direction of the third body portion for insertion of a handle is formed in the connection portion.