CN221035139U

CN221035139U - Shooting auxiliary rod

Info

Publication number: CN221035139U
Application number: CN202322628018.3U
Authority: CN
Inventors: 请求不公布姓名
Original assignee: Guangdong Sirui Optical Co Ltd
Current assignee: Guangdong Sirui Optical Co Ltd
Priority date: 2023-09-26
Filing date: 2023-09-26
Publication date: 2024-05-28
Anticipated expiration: 2033-09-26

Abstract

The utility model discloses a shooting auxiliary rod, which comprises an inner pipe, a switching pipe, an outer pipe and an end cover, wherein the end cover is provided with a first connecting hole, the moving direction of the inner pipe towards the first connecting hole is defined as a first direction, the switching pipe is provided with a first threaded connection part and a first clamping connection part, the first threaded connection part is in threaded connection with the inner pipe, the clamping connection part and the inner pipe are clamped to limit the inner pipe to move away from the switching pipe in the first direction, the outer pipe and the switching pipe are provided with a plurality of locking rods, and each locking rod extends through the outer pipe from outside to inside and is at least partially inserted into the switching pipe. According to the utility model, the shooting auxiliary rod is configured into the outer tube, the switching tube, the inner tube and the end cover, the switching tube in threaded connection with the outer tube, the inner tube and the end cover is provided with the first clamping part matched with the inner tube in a clamping way, and the outer tube and the switching tube are provided with the locking rod which extends from outside to inside to penetrate the outer tube and is at least partially inserted into the switching tube, so that the switching tube is stably connected with the inner tube/the outer tube, and the inner tube/the switching tube is prevented from falling off when threads fail or the bearing on the inner tube is overlarge.

Description

Shooting auxiliary rod

Technical Field

The utility model relates to the technical field of photographic equipment, in particular to a shooting auxiliary rod.

Background

The selfie stick is widely used as a photographic auxiliary device. The existing selfie stick comprises an outer tube, an inner tube and an end cover, wherein the inner tube is connected with photographic equipment, the inner tube and the outer tube are coaxially arranged and connected on the outer tube through the end cover, the inner tube is connected with the end cover through threads, and the end cover is connected with the outer tube through threads. Because the inner tube is connected to the outer tube through the end caps respectively in threaded connection with the inner tube and the outer tube, when the service time of the self-timer rod is long and/or photographic equipment carried on the inner tube is heavy, the inner tube and/or the end caps are easily separated from the outer tube due to the failure of the screw teeth, so that the photographic equipment is damaged.

Disclosure of utility model

The utility model aims to provide a shooting auxiliary rod, which solves the problem that when the use time of a self-timer rod is long and/or photographic equipment carried on the inner tube is heavy, the inner tube and/or the end cover are/is easily separated from the outer tube due to the failure of screw threads, so that photographic equipment is damaged.

The utility model is realized by the following technical scheme:

The shooting auxiliary rod comprises an inner pipe, a transfer pipe and an outer pipe which are sequentially sleeved from inside to outside, and an end cover which is abutted to the end part of the outer pipe, wherein the end cover is provided with a first connecting hole which enables the end part of the inner pipe to be exposed, the direction of movement of the inner pipe towards the first connecting hole is defined as a first direction, the transfer pipe is respectively in threaded connection with the inner pipe, the outer pipe is in threaded connection with the end cover, the transfer pipe is provided with a first threaded connection part and a first clamping connection part, the first clamping connection part is arranged on one side, far away from the end cover, of the first threaded connection part and is in clamping connection with the inner pipe to limit the inner pipe to move away from the transfer pipe in the first direction, the outer pipe and the transfer pipe are provided with a plurality of locking rods, the locking rods extend from outside to inside to penetrate the outer pipe and are at least partially inserted into the transfer pipe, and the locking rods are distributed at intervals in the circumferential direction of the outer pipe.

Further, the outer tube is provided with a plurality of second connecting holes, the switching tube is provided with a plurality of third connecting holes, the second connecting holes, the third connecting holes and the locking rods are in one-to-one correspondence, and the locking rods are inserted into the third connecting holes from the second connecting holes and are in threaded connection with the third connecting holes.

Further, the transfer pipe is provided with a plurality of positioning groove groups, each group of positioning grooves is composed of two positioning grooves which are oppositely arranged on the end face of the transfer pipe, which is opposite to the end cover, the bottom of each positioning groove is provided with a positioning hole, and a third connecting hole is arranged between any two adjacent positioning grooves.

Further, the inner annular wall of the transfer tube is provided with a first light wall area and an inner screw area, the first light wall area is far away from the end cover, the inner screw area is adjacent to the end cover and protrudes inwards to form the first clamping part at the juncture of the first light wall area and the inner screw area, and the inner screw area is provided with the first screw part; the outer annular wall of the inner tube is provided with a second light wall area and an outer screw area, the outer screw area is adjacent to the end cover and is provided with a second screw part in threaded connection with the first screw part, and the second light wall area is far away from the end cover and protrudes outwards to form a second clamping part in clamping fit with the first clamping part.

Further, the radial width of the overlapping part of the first clamping part and the second clamping part is far greater than the screw pitch of the first screw part and/or the second screw part.

Further, the radial width of the first clamping part accounts for 1/6 to 1/5 of the inner diameter of the switching tube.

Further, the first light wall area is abutted against the second light wall area, the first clamping portion is an annular plane extending from the first light wall area to the inner screw area, and the second clamping portion is an annular plane extending from the outer screw area to the second light wall area.

Further, the end cover is provided with an abutting portion and a plugging portion, the end face of the adapter tube, which is opposite to the end face of the end cover, is provided with a slot, the abutting portion is used for abutting against the end portion of the outer tube, the abutting portion extends around the axis of the outer tube to form the first connecting hole, and the plugging portion extends around the axis of the outer tube and stretches into the slot from the abutting portion to be in threaded connection with the slot.

Further, the slot is provided with an inner side wall and an outer side wall which are oppositely arranged in the radial direction, the inner side wall is inwards, the outer side wall is outwards, one side, opposite to the inner side wall, of the plug-in part is provided with a third screw-connection part in threaded connection with the slot, one side, opposite to the outer side wall, of the plug-in part is provided with a glue storage groove, and the glue storage groove extends around the circumference of the plug-in part.

Further, the adapter tube is provided with a fourth screw connection part positioned on the outer annular wall of the adapter tube, and the fourth screw connection part is an external thread extending from one end of the adapter tube to the other end of the adapter tube; the outer tube is provided with a plurality of guide strips which are arranged on the inner annular wall at intervals, the guide strips extend in the axial direction of the outer tube and are provided with fifth screw connection parts which are in threaded connection with the fourth screw connection parts, the inner annular wall of the outer tube is provided with sixth screw connection parts which are arranged around the second connecting holes, and the sixth screw connection parts are in threaded connection with the fourth screw connection parts.

The technical scheme has the advantages that the shooting auxiliary rod is configured into the outer tube, the transfer tube, the inner tube and the end cover, the transfer tube in threaded connection with the outer tube, the inner tube and the end cover is provided with the first clamping part matched with the inner tube in a clamping manner, and the outer tube and the transfer tube are provided with the locking rod which extends from outside to inside to penetrate through the outer tube and is at least partially inserted into the transfer tube, so that the connection between the transfer tube and the inner tube/the outer tube is stable, the inner tube is prevented from falling off when the screw tooth between the inner tube and the transfer tube fails or the bearing on the inner tube is overlarge, and the problem that photographic equipment is damaged when the screw tooth between the transfer tube and the outer tube fails or the bearing on the inner tube is avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are required to be used in the description of the embodiments will be briefly described below.

Fig. 1 is a perspective view of a photographing auxiliary lever according to an embodiment;

fig. 2 is an exploded view of a photographing auxiliary lever according to an embodiment of the present disclosure;

fig. 3 is a sectional view of a photographing auxiliary lever according to an embodiment;

FIG. 4 is an enlarged view of a portion of FIG. 3 at A;

FIG. 5 is a perspective view of a transfer tube in an embodiment;

FIG. 6 is a second perspective view of a transfer tube in an embodiment;

FIG. 7 is a perspective view of an inner tube in an embodiment;

FIG. 8 is a perspective view of an end cap in an embodiment;

FIG. 9 is a perspective view of an outer tube in an embodiment;

fig. 10 is a partial enlarged view at B in fig. 9.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Examples: as shown in fig. 1 to 10, the photographing auxiliary rod comprises an inner tube 1, a transfer tube 2 and an outer tube 3 which are sequentially sleeved from inside to outside, and an end cover 4 abutting against the end part of the outer tube 3, wherein the end cover 4 is provided with a first connecting hole 401 for exposing the end part of the inner tube 1, the direction in which the inner tube 1 moves towards the first connecting hole 401 is defined as a first direction, the transfer tube 2 is respectively in threaded connection with the inner tube 1, the outer tube 3 and the end cover 4, the transfer tube 2 is provided with a first threaded connection part 201 and a first clamping part 202, the first threaded connection part 201 is in threaded connection with the inner tube 1, the first clamping part 202 is arranged on one side of the first threaded connection part 201 away from the end cover 4 and is clamped with the inner tube 1 to limit the inner tube 1 to move away from the transfer tube 2 in the first direction, the outer tube 3 and the transfer tube 2 are provided with a plurality of locking rods 5, each locking rod 5 extends from outside to inside to penetrate the outer tube 3 and is at least partially inserted into the transfer tube 2, and the plurality of locking rods 5 are distributed at intervals in the circumferential direction of the outer tube 3. The present embodiment provides a photographing auxiliary rod to solve the problem that when the use time of the self-photographing rod is long and/or the photographing apparatus carried on the inner tube is heavy, the inner tube and/or the end cover are easily separated from the outer tube due to the failure of the screw thread, and the photographing apparatus is damaged, mainly by configuring the photographing auxiliary rod into the outer tube 3, the transfer tube 2, the inner tube 1 and the end cover 4, and configuring the first clamping portion 202 clamped with the inner tube 1 on the transfer tube 2 in threaded connection with the outer tube 3, the inner tube 1 and the end cover 4, and configuring the locking rod 5 extending from outside to inside to penetrate the outer tube 3 and at least partially inserted into the transfer tube 2 on the outer tube 3 and the transfer tube 2, the connection between the transfer tube 2 and the inner tube/outer tube is stable, so that the problem that the inner tube 1 is damaged when the screw thread between the inner tube 1 and the transfer tube 2 fails or the bearing on the inner tube 1 is excessively large is avoided, and the problem that the transfer tube 2 is damaged when the screw thread between the inner tube 3 and the outer tube 1 is excessively heavy is damaged is avoided, and the photographing apparatus is prevented.

In the embodiment of the present utility model, the outer tube 3 has a plurality of second connecting holes 301, the adapter tube 2 has a plurality of third connecting holes 203, the plurality of second connecting holes 301, the plurality of third connecting holes 203 and the plurality of locking rods 5 are in one-to-one correspondence, and the locking rods 5 are inserted into the third connecting holes 203 from the second connecting holes 301 and are in threaded connection with the third connecting holes 203. Since the locking lever 5 is inserted into the third coupling hole 203 from the second coupling hole 301 and is screw-coupled with the third coupling hole 203, the connection of the locking lever 5 with the outer tube 3 and the adapter tube 2 is stabilized.

In the embodiment of the present utility model, the portion of the locking rod 5 inserted into the third connecting hole 203 is at least 1/2 of the hole length of the third connecting hole 203, more preferably, the third connecting hole 203 is a through hole, and the locking rod 5 is inserted into the third connecting hole 203 from the second connecting hole 301 and abuts against the outer annular wall of the inner tube 1. Since the portion of the locking rod 5 inserted into the third connecting hole 203 occupies at least 1/2 of the hole length of the third connecting hole 203, the connection between the locking rod 5 and the outer tube 3 and the connection tube 2 are stable, and more preferably, the third connecting hole 203 is a through hole, and the locking rod 5 is inserted into the third connecting hole 203 from the second connecting hole 301 and is abutted on the outer annular wall of the inner tube 1, so that the connection between the locking rod 5 and the outer tube 3 and the connection tube 2 are stable, and the inner tube 1 has good assembly stability and is prevented from falling off.

In the embodiment of the utility model, the adapter tube 2 is provided with a plurality of groups of positioning grooves, each group of positioning grooves consists of two positioning grooves 204 oppositely arranged on the end surface of the adapter tube 2 facing away from the end cover 4, and the bottom of each positioning groove 204 is provided with a positioning hole 205. The positioning hole 205 is used in cooperation with the assembly rocker, and is used for screwing the adapter tube 2 into the outer tube 3 entirely, and aligning the third connecting hole 203 with the second connecting hole 301 during rotation. The positioning grooves 204 oppositely arranged on the end surface of the adapter tube 2 facing away from the end cover 4 are provided with the positioning holes 205, so that the adapter tube 2 can be conveniently screwed into the outer tube 3, and the third connecting hole 203 and the second connecting hole 301 can be conveniently aligned and installed.

In the embodiment of the utility model, the inner annular wall of the adapter tube 2 is provided with a first light wall area 206 and an inner screw area 207, the first light wall area 206 is far away from the end cover 4, the inner screw area 207 is adjacent to the end cover 4 and protrudes inwards to form a first clamping part 202 at the juncture of the first light wall area 206 and the inner screw area 207, the inner screw area 207 is provided with a first screw part 201, the outer annular wall of the inner tube 1 is provided with a second light wall area 101 and an outer screw area 102, the outer screw area 102 is adjacent to the end cover 4 and is provided with a second screw part 103 in threaded connection with the first screw part 201, and the second light wall area 101 is far away from the end cover 4 and protrudes outwards to form a second clamping part 104 in clamping fit with the first clamping part 202. The adapter tube 2 and the inner tube 1 adopt the clamping structure, the structure is compact and reasonable, and the space utilization rate is high.

In the embodiment of the present utility model, the radial width of the overlapping portion a of the first clamping portion 202 and the second clamping portion 104 is much greater than the pitch B of the first threaded portion 201 and/or the second threaded portion 103. Specifically, the radial width of the overlapping portion a is two to three times the pitch B. Since the radial width of the overlapping portion a of the first clamping portion 202 and the second clamping portion 104 is far greater than the pitch B of the first threaded portion 201 and/or the second threaded portion 103, that is, the bearing capacity of the clamping structure of the adapter tube 2 and the inner tube 1 is far greater than the bearing capacity of the threaded connection structure of the adapter tube 2 and the inner tube 1, the inner tube 1 can be prevented from falling off when the screw thread between the inner tube 1 and the adapter tube 2 fails or the bearing on the inner tube 1 is too large.

In the embodiment of the present utility model, the second light wall area 101 abuts against the first light wall area 206, the first clamping portion 202 is an annular plane extending from the first light wall area 206 to the inner screw area 207, and the second clamping portion 104 is an annular plane extending from the outer screw area 102 to the second light wall area 101. Since the second light wall region 101 is abutted against the first light wall region 206, the first clamping portion 202 is an annular plane extending from the first light wall region 206 to the inner threaded region 207, and the second clamping portion 104 is an annular plane extending from the outer threaded region 102 to the second light wall region 101, the contact area between the first clamping portion 202 and the second clamping portion 104 is maximized, and the bearing capacity of the clamping structure is improved.

In the embodiment of the present utility model, the radial width of the first clamping portion 202 occupies 1/6 to 1/5 of the inner diameter of the adapter tube 2. Since the radial width of the first clamping portion 202 occupies 1/6 to 1/5 of the inner diameter of the adapter tube 2, the clamping load-bearing capacity of the first clamping portion 202 and the second clamping portion 104 is good.

In the embodiment of the present utility model, the second clamping portion 104 abuts against the first clamping portion 202 when the inner tube 1 is partially inserted into the first connecting hole 401. Since the second engagement portion 104 abuts against the first engagement portion 202 when the inner tube 1 is partially inserted into the first connecting hole 401, the inner tube 1 can be prevented from falling off when the screw between the inner tube 1 and the adapter tube 2 fails or the load on the inner tube 1 is excessively large.

In the embodiment of the utility model, the end cover 4 is provided with an abutting part 402 and a plugging part 403, the end face of the adapter tube 2, which is opposite to the end cover 4, is provided with the slot 208, the abutting part 402 is used for abutting against the end part of the outer tube 3, the abutting part 402 extends around the axis of the outer tube 3 to form a first connecting hole 401, and the plugging part 403 extends around the axis of the outer tube 3 and extends from the abutting part 402 into the slot 208 to be in threaded connection with the slot 208. Since the end cover 4 has the abutting portion 402 and the plugging portion 403, and the adapter tube 2 has the slot 208 in threaded connection with the plugging portion 403, the end cover 4 and the adapter tube 2 have good connection stability, and are not easy to fall off.

In the embodiment of the utility model, the slot 208 is provided with an inner side wall 209 and an outer side wall 210 which are oppositely arranged in the radial direction, the inner side wall 209 is positioned inwards, the outer side wall 210 is positioned outwards, a third screw connection part 404 which is in threaded connection with the slot 208 is arranged on the side, facing the inner side wall 209, of the plug-in part 403, a glue storage groove 405 is arranged on the side, facing the outer side wall 210, of the plug-in part 403, and the glue storage groove 405 extends around the circumferential direction of the plug-in part 403. During assembly, glue is injected into the glue storage groove 405 before the end cover 4 is screwed into the slot 208, and the glue in the glue storage groove 405 overflows the glue storage groove 405 when the end cover 4 is screwed into the slot 208 and after the end cover 4 is screwed into the slot 208, so that the stability of connection between the end cover 4 and the adapter tube 2 is improved.

In the embodiment of the present utility model, the adapter tube 2 has a fourth screw connection portion 211 located on an outer circumferential wall thereof, the fourth screw connection portion 211 is an external screw thread extending from one end of the adapter tube 2 to the other end of the adapter tube 2, the outer tube 3 has a plurality of guide strips 302 spaced apart on an inner circumferential wall thereof, the plurality of guide strips 302 extend in an axial direction of the outer tube 3 and have a fifth screw connection portion 303 in screw connection with the fourth screw connection portion 211, the inner circumferential wall of the outer tube 3 has a sixth screw connection portion 304 disposed around the second connection hole 301, and the sixth screw connection portion 304 is in screw connection with the fourth screw connection portion 211. The external threads on the outer annular wall of the adapter tube 2 extend from one axial end to the other axial end, so that the distribution area is large, and the adapter tube 2 and the outer tube 3 have good connection stability. Since the outer tube 3 has the plurality of guide strips 302 (the guide strips 302 protrude from the inner annular wall of the outer tube 3) arranged at intervals on the inner annular wall thereof, the guide strips 302 have the fifth screw connection portion 303 in threaded connection with the fourth screw connection portion 211, thereby avoiding weakening of the deformation resistance of the outer tube 3 due to direct processing of the fifth screw connection portion 303 on the inner annular wall of the outer tube 3, and enabling the outer tube 3 to have good structural strength. The inner annular wall of the outer tube 3 is provided with a sixth threaded connection part 304 which is arranged around the second connecting hole 301 and is in threaded connection with the fourth threaded connection part 211, so that the outer tube 3 and the adapter tube 2 have good connection stability.

In the embodiment of the present utility model, the inner circumferential wall of the inner tube 1 has a seventh screw joint 105.

It should be understood that the terms "first," "second," and the like are used herein to describe various information, but such information should not be limited to these terms, which are used merely to distinguish one type of information from another. For example, a "first" message may also be referred to as a "second" message, and similarly, a "second" message may also be referred to as a "first" message, without departing from the scope of the utility model. Furthermore, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," and the like refer to an orientation or positional relationship based on that shown in the drawings, merely for convenience in describing the present utility model and simplifying the description, and do not denote or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present utility model.

The foregoing description of one or more embodiments provided in connection with the specific disclosure is not intended to limit the practice of the utility model to such description. Any approximation, or substitution of the technical deduction or substitution made for the technical deduction of the present utility model based on the inventive method, structure, etc. shall be considered as protection of the present utility model.

Claims

1. The shooting auxiliary rod is characterized by comprising an inner pipe, a switching pipe, an outer pipe and an end cover, wherein the inner pipe, the switching pipe and the outer pipe are sequentially sleeved from inside to outside, the end cover is abutted to the end part of the outer pipe, the end cover is provided with a first connecting hole for exposing the end part of the inner pipe, the moving direction of the inner pipe towards the first connecting hole is defined as a first direction, the switching pipe is respectively in threaded connection with the inner pipe, the outer pipe and the end cover, the switching pipe is provided with a first threaded connection part and a first clamping part, the first threaded connection part is in threaded connection with the inner pipe, and the first clamping part is arranged on one side of the first threaded connection part far away from the end cover and is clamped with the inner pipe to limit the inner pipe to move away from the switching pipe in the first direction;

The outer tube and the transfer tube are provided with a plurality of locking rods, each locking rod extends from outside to inside to penetrate through the outer tube and is at least partially inserted into the transfer tube, and the locking rods are distributed at intervals in the circumferential direction of the outer tube.

2. The photographing auxiliary lever according to claim 1, wherein the outer tube has a plurality of second coupling holes, the adapter tube has a plurality of third coupling holes, the plurality of second coupling holes, the plurality of third coupling holes and the plurality of locking levers are in one-to-one correspondence, and the locking levers are inserted into the third coupling holes from the second coupling holes and are screw-coupled with the third coupling holes.

3. The shooting auxiliary rod as defined in claim 2, wherein the adapter tube is provided with a plurality of positioning groove groups, each group of positioning grooves is composed of two positioning grooves oppositely arranged on the end face of the adapter tube facing away from the end cover, positioning holes are formed in the bottom of each positioning groove, and the third connecting hole is formed between any two adjacent positioning grooves.

4. The photographing auxiliary rod as claimed in claim 1, wherein an inner annular wall of the adapter tube has a first light wall region and an inner screw region, the first light wall region being remote from the end cover, the inner screw region being adjacent to the end cover and protruding inward to form the first clamping portion at a junction of the first light wall region and the inner screw region, the inner screw region having the first screw portion;

The outer annular wall of the inner tube is provided with a second light wall area and an outer screw area, the outer screw area is adjacent to the end cover and is provided with a second screw part in threaded connection with the first screw part, and the second light wall area is far away from the end cover and protrudes outwards to form a second clamping part in clamping fit with the first clamping part.

5. The photographing auxiliary lever according to claim 4, wherein a radial width of a superimposed portion of the first and second clamping portions is substantially larger than a pitch of the first and/or second screw portions.

6. The photographing auxiliary lever according to claim 4 or 5, wherein the radial width of the first clamping portion is 1/6 to 1/5 of the inner diameter of the adapter tube.

7. The photographing auxiliary lever according to claim 4 or 5, wherein the first light wall region abuts against the second light wall region, the first engaging portion is an annular plane extending from the first light wall region to the inner screw region, and the second engaging portion is an annular plane extending from the outer screw region to the second light wall region.

8. The shooting auxiliary bar as claimed in claim 1, wherein the end cap has an abutment portion for abutting against an end portion of the outer tube, and a socket portion extending around an axis of the outer tube to form the first connection hole, and an end face of the adapter tube facing the end cap is provided with a socket, and the socket portion extends around the axis of the outer tube and extends from the abutment portion into the socket to be screwed with the socket.

9. The photographing auxiliary rod as claimed in claim 8, wherein the socket has an inner sidewall and an outer sidewall disposed opposite to each other in a radial direction, the inner sidewall is disposed inward, the outer sidewall is disposed outward, a third screw portion screwed with the socket is disposed on a side of the socket facing the inner sidewall, a glue storage groove is disposed on a side of the socket facing the outer sidewall, and the glue storage groove extends around a circumference of the socket.

10. The photographing auxiliary lever according to claim 2, wherein the adapter tube has a fourth screw portion on an outer circumferential wall thereof, the fourth screw portion being an external screw thread extending from one end of the adapter tube to the other end of the adapter tube;

The outer tube is provided with a plurality of guide strips which are arranged on the inner annular wall at intervals, extend in the axial direction of the outer tube and are provided with fifth screw connection parts which are in screw connection with the fourth screw connection parts;

The inner annular wall of the outer tube is provided with a sixth threaded connection part which is arranged around the second connecting hole, and the sixth threaded connection part is in threaded connection with the fourth threaded connection part.