Shooting auxiliary rod

Abstract

A shooting auxiliary rod disclosed by the present invention comprises an inner tube, an adapter tube, an outer tube and an end cover, the end cover is provided with a first connecting hole, the moving direction of the inner tube towards the first connecting hole is defined as a first direction, the adapter tube is provided with a first screw joint part and a first clamping part, and the first screw joint part is in threaded connection with the inner tube; the first clamping part is clamped with the inner pipe to limit the inner pipe to move away from the adapter pipe in the first direction, a plurality of locking rods are arranged on the outer pipe and the adapter pipe, and each locking rod extends from outside to inside, penetrates through the outer pipe and is at least partially inserted into the adapter pipe. The shooting auxiliary rod comprises an outer pipe, an adapter pipe, an inner pipe and an end cover, the adapter pipe in threaded connection with the outer pipe, the inner pipe and the end cover is provided with a first clamping part in clamping fit with the inner pipe, and the outer pipe and the adapter pipe are provided with a locking rod which extends from outside to inside, penetrates through the outer pipe and is at least partially inserted into the adapter pipe. The connection between the adapter pipe and the inner / outer pipe is stable, and the inner pipe / adapter pipe is prevented from falling off when the screw teeth are invalid or the bearing on the inner pipe is too large.

Description

Technical Field

[0001] The invention relates to the technical field of photographic equipment, in particular to a shooting auxiliary rod. Background Art

[0002] As a kind of photography auxiliary equipment, the selfie stick is widely used. The existing selfie stick includes an outer tube, an inner tube and an end cap, the inner tube is used to connect with the photographic equipment, the inner tube is coaxially arranged with the outer tube and connected to the outer tube through the end cap, the inner tube is threadedly connected with the end cap, and the end cap is threadedly connected with the outer tube. Since the inner tube is connected to the outer tube through the end caps respectively threadedly connected with the inner / outer tubes, when the selfie stick is used for a long time and / or the photographic equipment carried on the inner tube is heavy, the inner tube and / or the end cap are easily separated from the outer tube due to the failure of the screw thread, causing damage to the photographic equipment. Summary of the invention

[0003] The object of the present invention is to provide a shooting auxiliary rod to solve the problem that in the existing selfie stick, the inner tube is connected to the outer tube through the end caps respectively threadedly connected to the inner / outer tubes. When the selfie stick is used for a long time and / or the photographic equipment carried on the inner tube is heavy, the inner tube and / or the end cap are easily separated from the outer tube due to the failure of the screw thread, causing damage to the photographic equipment.

[0004] The present invention is achieved through the following technical solutions:

[0005] A shooting auxiliary rod comprises an inner tube, an adapter tube and an outer tube which are sequentially sleeved from the inside to the outside, and an end cap abutting against the end of the outer tube, the end cap having a first connecting hole to expose the end of the inner tube, the direction in which the inner tube moves toward the first connecting hole is defined as a first direction, the adapter tube is threadedly connected to the inner tube, the outer tube and the end cap respectively, the adapter tube has a first screw connection portion and a first clamping portion, the first screw connection portion is threadedly connected to the inner tube, the first clamping portion is arranged on a side of the first screw connection portion away from the end cap and is clamped with the inner tube to limit the inner tube from moving away from the adapter tube in the first direction, a plurality of locking rods are provided on the outer tube and the adapter tube, each of the locking rods extends from the outside to the inside through the outer tube and is at least partially inserted into the adapter tube, and the plurality of locking rods are spaced apart in the circumferential direction of the outer tube.

[0006] Furthermore, the outer tube has a plurality of second connecting holes, the adapter tube has a plurality of third connecting holes, the plurality of second connecting holes, the plurality of third connecting holes and the plurality of locking rods correspond one to one, and the locking rods are inserted from the second connecting holes into the third connecting holes and are threadedly connected to the third connecting holes.

[0007] Furthermore, the adapter tube has a plurality of positioning groove groups, each group of positioning grooves consists of two positioning grooves arranged opposite to each other on the end surface of the adapter tube facing away from the end cover, a positioning hole is provided at the bottom of the positioning groove, and the third connecting hole is provided between any two adjacent positioning grooves.

[0008] Further, the inner annular wall of the transfer tube has a first plain wall area and an inner threaded area, the first plain wall area is far away from the end cover, the inner threaded area is adjacent to the end cover and protrudes inward to form the first clamping portion at the junction of the first plain wall area and the inner threaded area, and the inner threaded area has the first threaded portion; the outer annular wall of the inner tube has a second plain wall area and an outer threaded area, the outer threaded area is adjacent to the end cover and has a second threaded portion threadedly connected to the first threaded portion, and the second plain wall area is far away from the end cover and protrudes outward to form a second clamping portion that is clamped and matched with the first clamping portion.

[0009] Furthermore, a radial width of an overlapping portion of the first clamping portion and the second clamping portion is much larger than a pitch of the first threaded portion and / or the second threaded portion.

[0010] Furthermore, the radial width of the first clamping portion accounts for 1 / 6 to 1 / 5 of the inner diameter of the adapter tube.

[0011] Furthermore, the first light wall area abuts against the second light wall area, the first clamping portion is an annular plane extending from the first light wall area to the inner spiral area, and the second clamping portion is an annular plane extending from the outer spiral area to the second light wall area.

[0012] Furthermore, the end cover has an abutment portion and an insertion portion, and a slot is provided on the end surface of the adapter tube facing the end cover, the abutment portion is used to abut against the end of the outer tube, the abutment portion extends around the axis of the outer tube to form the first connecting hole, and the insertion portion extends around the axis of the outer tube and extends from the abutment portion into the slot to be threadedly connected to the slot.

[0013] Furthermore, the slot has an inner wall and an outer wall which are arranged opposite to each other in the radial direction, the inner wall is closer to the inside, and the outer wall is closer to the outside, a third threaded portion which is threadedly connected to the slot is provided on the side of the plug-in portion facing the inner wall, and a glue storage groove is provided on the side of the plug-in portion facing the outer wall, and the glue storage groove extends around the circumference of the plug-in portion.

[0014] Furthermore, the adapter tube has a fourth threaded connection portion located on its outer annular wall, and the fourth threaded connection portion is an external thread extending from one end of the adapter tube to the other end of the adapter tube; the outer tube has a plurality of guide strips spaced apart on its inner annular wall, and the plurality of guide strips extend in the axial direction of the outer tube and have a fifth threaded connection portion threadedly connected to the fourth threaded connection portion, and the inner annular wall of the outer tube has a sixth threaded connection portion arranged around the second connecting hole, and the sixth threaded connection portion is threadedly connected to the fourth threaded connection portion.

[0015] The advantage of the technical solution is that by configuring the shooting auxiliary rod into an outer tube, an adapter tube, an inner tube and an end cap, and arranging a first clamping portion that is clamped and cooperates with the inner tube on the adapter tube that is threadedly connected to the outer tube, the inner tube and the end cap, and arranging a locking rod that extends from the outside to the inside, penetrates the outer tube and is at least partially inserted into the adapter tube on the outer tube and the adapter tube, the connection between the adapter tube and the inner / outer tube is stabilized, and the inner tube is prevented from falling off when the screw thread between the inner tube and the adapter tube fails or the load on the inner tube is too large, and the adapter tube is prevented from falling off when the screw thread between the inner tube and the adapter tube fails or the load on the inner tube is too large, thereby damaging the photographic equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0018] Figure 1 is a stereoscopic diagram of a shooting auxiliary rod disclosed in an embodiment;

[0019] Figure 2 is an exploded view of a shooting auxiliary lever disclosed in an embodiment;

[0020] Figure 3 is a cross-sectional view of a shooting auxiliary rod disclosed in an embodiment;

[0021] Figure 4 yes Figure 3 A partial enlarged view of the middle A;

[0022] Figure 5 The three-dimensional diagram of the transfer tube in the embodiment Figure 1 ;

[0023] Figure 6 The three-dimensional diagram of the transfer tube in the embodiment Figure 2 ;

[0024] Figure 7 is a perspective view of the inner tube in the embodiment;

[0025] Figure 8 is a three-dimensional diagram of the end cap in the embodiment;

[0026] Fig. 9 is a perspective view of the outer tube in the embodiment;

[0027] Fig.10 yes Fig. 9 A partial enlarged view of point B in the middle. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Example: Figure 1-10As shown, the shooting auxiliary rod includes an inner tube 1, an adapter tube 2 and an outer tube 3 which are sequentially sleeved from the inside to the outside, and an end cover 4 abutting against the end of the outer tube 3, the end cover 4 has a first connecting hole 401 to expose the end of the inner tube 1, and the direction in which the inner tube 1 moves toward the first connecting hole 401 is defined as a first direction, the adapter tube 2 is threadedly connected to the inner tube 1, the outer tube 3 and the end cover 4, respectively, the adapter tube 2 has a first screw connection portion 201 and a first clamping portion 202, the first screw connection portion 201 is threadedly connected to the inner tube 1, the first clamping portion 202 is provided on a side of the first screw connection portion 201 away from the end cover 4 and is clamped with the inner tube 1 to limit the inner tube 1 from moving away from the adapter tube 2 in the first direction, a plurality of locking rods 5 are provided on the outer tube 3 and the adapter tube 2, each locking rod 5 extends from the outside to the inside, penetrates the outer tube 3 and is at least partially inserted into the adapter 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 shooting auxiliary rod to solve the problem that in the existing selfie stick, the inner tube is connected to the outer tube 3 through the end cap 4 threadedly connected to the inner / outer tube respectively. When the selfie stick is used for a long time and / or the photographic equipment carried on the inner tube is heavy, the inner tube and / or the end cap is easily separated from the outer tube due to the failure of the screw thread, causing damage to the photographic equipment. The shooting auxiliary rod is mainly configured to include the outer tube 3, the adapter tube 2, the inner tube 1 and the end cap 4, and the first clamping portion 202 clamped with the inner tube 1 is arranged on the adapter tube 2 threadedly connected to the outer tube 3, the inner tube 1 and the end cap 4, and the locking rod 5 extending from the outside to the inside through the outer tube 3 and at least partially inserted into the adapter tube 2 is arranged on the outer tube 3 and the adapter tube 2, so that the connection between the adapter tube 2 and the inner / outer tube is stable, and the inner tube 1 is prevented from falling off when the screw thread between the inner tube 1 and the adapter tube 2 fails or the load on the inner tube 1 is too heavy, and the adapter tube 2 is prevented from falling off when the screw thread between the inner tube 1 and the outer tube 3 fails or the load on the inner tube 1 is too heavy, thereby damaging the photographic equipment.

[0030] In the embodiment of the present invention, 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 correspond to each other, and the locking rods 5 are inserted from the second connecting holes 301 into the third connecting holes 203 and are threadedly connected with the third connecting holes 203. Since the locking rods 5 are inserted from the second connecting holes 301 into the third connecting holes 203 and are threadedly connected with the third connecting holes 203, the connection between the locking rods 5 and the outer tube 3 and the adapter tube 2 is stable.

[0031] In the embodiment of the present invention, the portion of the locking rod 5 inserted into the third connecting hole 203 accounts for at least 1 / 2 of the 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 accounts for at least 1 / 2 of the length of the third connecting hole 203, the connection between the locking rod 5 and the outer tube 3 and the adapter tube 2 is stable. 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. Therefore, the connection between the locking rod 5 and the outer tube 3 and the adapter tube 2 is stable, and the inner tube 1 has good assembly stability to prevent it from falling off.

[0032] In the embodiment of the present invention, the adapter tube 2 has a plurality of groups of positioning grooves, each group of positioning grooves is composed of two positioning grooves 204 arranged opposite to each other on the end surface of the adapter tube 2 facing away from the end cover 4, and a positioning hole 205 is arranged at the bottom of the positioning groove 204. The positioning hole 205 is used in conjunction with the assembly rocker to screw the adapter tube 2 into the outer tube 3 and align the third connecting hole 203 with the second connecting hole 301 during the rotation process. Since the positioning grooves 204 arranged opposite to each other on the end surface of the adapter tube 2 facing away from the end cover 4 are provided with the positioning holes 205, it is convenient to screw the adapter tube 2 into the outer tube 3 and to facilitate the alignment and installation of the third connecting hole 203 and the second connecting hole 301.

[0033] In the embodiment of the present invention, the inner ring wall of the adapter tube 2 has a first plain wall area 206 and an inner thread area 207, the first plain wall area 206 is far away from the end cover 4, the inner thread area 207 is adjacent to the end cover 4 and protrudes inward to form a first clamping portion 202 at the junction of the first plain wall area 206 and the inner thread area 207, the inner thread area 207 has a first threaded portion 201, the outer ring wall of the inner tube 1 has a second plain wall area 101 and an outer thread area 102, the outer thread area 102 is adjacent to the end cover 4 and has a second threaded portion 103 threadedly connected to the first threaded portion 201, and the second plain wall area 101 is far away from the end cover 4 and protrudes outward to form a second clamping portion 104 clamped and matched with the first clamping portion 202. The adapter tube 2 and the inner tube 1 adopt the above-mentioned clamping structure, which is compact and reasonable in structure and has high space utilization.

[0034] In the embodiment of the present invention, the radial width of the overlapping portion A of the first clamping portion 202 and the second clamping portion 104 is much larger 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 much larger than the pitch B of the first threaded portion 201 and / or the second threaded portion 103, that is, the load-bearing capacity of the clamping structure of the adapter tube 2 and the inner tube 1 is much larger than the load-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 thread between the inner tube 1 and the adapter tube 2 fails or the load on the inner tube 1 is too large.

[0035] In the embodiment of the present invention, 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 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, the contact area between the first clamping portion 202 and the second clamping portion 104 is maximized, thereby improving the load-bearing capacity of the clamping structure.

[0036] In the embodiment of the present invention, the radial width of the first clamping portion 202 accounts for 1 / 6 to 1 / 5 of the inner diameter of the adapter tube 2. Since the radial width of the first clamping portion 202 accounts for 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.

[0037] In the embodiment of the present invention, 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 clamping portion 104 abuts against the first clamping 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 thread between the inner tube 1 and the transfer tube 2 fails or the load on the inner tube 1 is too large.

[0038] In the embodiment of the present invention, the end cap 4 has an abutment portion 402 and an insertion portion 403, and the end surface of the adapter tube 2 facing the end cap 4 is provided with a slot 208, the abutment portion 402 is used to abut against the end of the outer tube 3, the abutment portion 402 extends around the axis of the outer tube 3 to form a first connecting hole 401, and the insertion portion 403 extends around the axis of the outer tube 3 and extends from the abutment portion 402 into the slot 208 and is threadedly connected to the slot 208. Since the end cap 4 has the abutment portion 402 and the insertion portion 403, and the adapter tube 2 has the slot 208 threadedly connected to the insertion portion 403, the end cap 4 and the adapter tube 2 have good connection stability and are not easy to fall off.

[0039] In the embodiment of the present invention, the slot 208 has an inner side wall 209 and an outer side wall 210 which are arranged opposite to each other in the radial direction, the inner side wall 209 is closer to the inside, and the outer side wall 210 is closer to the outside, a third threaded portion 404 which is threadedly connected to the slot 208 is provided on the side of the plug-in portion 403 facing the inner side wall 209, and a glue storage groove 405 is provided on the side of the plug-in portion 403 facing the outer side wall 210, and the glue storage groove 405 extends around the circumference of the plug-in portion 403. During assembly, glue is first 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 from the glue storage groove 405 when and after the end cover 4 is screwed into the slot 208, thereby improving the stability of the connection between the end cover 4 and the adapter tube 2.

[0040] In the embodiment of the present invention, the adapter tube 2 has a fourth threaded portion 211 located on its outer ring wall, and the fourth threaded portion 211 is an external 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 bars 302 arranged at intervals on its inner ring wall, and the plurality of guide bars 302 extend in the axial direction of the outer tube 3 and have a fifth threaded portion 303 threadedly connected to the fourth threaded portion 211. The inner ring wall of the outer tube 3 has a sixth threaded portion 304 arranged around the second connecting hole 301, and the sixth threaded portion 304 is threadedly connected to the fourth threaded portion 211. Since the external thread on the outer ring wall of the adapter tube 2 extends from one axial end to the other axial end thereof, the distribution area is large, so that the adapter tube 2 and the outer tube 3 have good connection stability. In addition, since the outer tube 3 has a plurality of guide strips 302 arranged at intervals on its inner ring wall (the guide strips 302 protrude from the inner ring wall of the outer tube 3), and the guide strips 302 have a fifth threaded portion 303 threadedly connected to the fourth threaded portion 211, it is avoided that the fifth threaded portion 303 is directly processed on the inner ring wall of the outer tube 3, which would weaken the anti-deformation ability of the outer tube 3, and the outer tube 3 has good structural strength. In addition, since the inner ring wall of the outer tube 3 has a sixth threaded portion 304 threadedly connected to the fourth threaded portion 211 arranged around the second connecting hole 301, the outer tube 3 and the transfer tube 2 have good connection stability.

[0041] In the embodiment of the present invention, the inner annular wall of the inner tube 1 has a seventh threaded portion 105 .

[0042] It should be understood that the terms "first", "second", etc. are used in the present invention to describe various information, but such information should not be limited to these terms, and these terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, the "first" information may also be referred to as the "second" information, and similarly, the "second" information may also be referred to as the "first" information. In addition, the terms "center of a circle", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0043] As described above, one or more implementation methods are provided in combination with specific contents, and the specific implementation of the present invention is not limited to these descriptions. Any similarity or similarity with the method, structure, etc. of the present invention, or any technical deduction or replacement based on the concept of the present invention shall be regarded as the protection of the present invention.

Claims

1. A shooting auxiliary lever, characterized in that: The invention comprises an inner tube, a transfer tube and an outer tube which are sleeved in sequence from the inside to the outside, and an end cap abutting against the end of the outer tube, the end cap having a first connecting hole for exposing the end of the inner tube, the direction in which the inner tube moves toward the first connecting hole is defined as a first direction, the transfer tube is threadedly connected with the inner tube, the outer tube and the end cap respectively, the transfer tube has a first screw connection part and a first clamping part, the first screw connection part is threadedly connected with the inner tube, the first clamping part is arranged on a side of the first screw connection part away from the end cap and is clamped with the inner tube to limit the inner tube from moving away from the transfer tube in the first direction; A plurality of locking rods are provided on the outer tube and the adapter tube. Each of the locking rods extends from the outside to the inside, penetrates the outer tube and is at least partially inserted into the adapter tube. The plurality of locking rods are spaced apart in the circumferential direction of the outer tube.

2. The shooting auxiliary lever according to claim 1, characterized in that: The outer tube has a plurality of second connecting holes, the adapter tube has a plurality of third connecting holes, the plurality of second connecting holes, the plurality of third connecting holes and the plurality of locking rods correspond one to one, and the locking rods are inserted from the second connecting holes into the third connecting holes and are threadedly connected with the third connecting holes.

3. The shooting auxiliary lever according to claim 2, characterized in that: The adapter tube has a plurality of positioning groove groups, each group of positioning grooves consists of two positioning grooves arranged opposite to each other on the end surface of the adapter tube facing away from the end cover, a positioning hole is provided at the bottom of the positioning groove, and the third connecting hole is provided between any two adjacent positioning grooves.

4. The shooting auxiliary lever according to claim 1, characterized in that: The inner ring wall of the transfer tube has a first plain wall area and an inner thread area, the first plain wall area is far away from the end cover, the inner thread area is adjacent to the end cover and protrudes inward to form the first clamping portion at the junction of the first plain wall area and the inner thread area, and the inner thread area has the first threaded portion; The outer annular wall of the inner tube has a second plain wall area and an outer threaded area, the outer threaded area is adjacent to the end cover and has a second threaded portion threadedly connected to the first threaded portion, and the second plain wall area is away from the end cover and protrudes outward to form a second clamping portion that is clamped and matched with the first clamping portion.

5. The shooting auxiliary lever according to claim 4, characterized in that: The radial width of the overlapping portion of the first clamping portion and the second clamping portion is much larger than the pitch of the first threaded portion and / or the second threaded portion.

6. The shooting auxiliary lever according to claim 4 or 5, characterized in that: The radial width of the first clamping portion accounts for 1 / 6 to 1 / 5 of the inner diameter of the adapter tube.

7. The shooting auxiliary lever according to claim 4 or 5, characterized in that: The first light wall area abuts against the second light wall area, the first clamping portion is an annular plane extending from the first light wall area to the inner spiral area, and the second clamping portion is an annular plane extending from the outer spiral area to the second light wall area.

8. The shooting auxiliary lever according to claim 1, characterized in that: The end cover has an abutment portion and an insertion portion, and a slot is provided on the end surface of the adapter tube facing the end cover. The abutment portion is used to abut against the end of the outer tube, and the abutment portion extends around the axis of the outer tube to form the first connecting hole. The insertion portion extends around the axis of the outer tube and extends from the abutment portion into the slot to be threadedly connected to the slot.

9. The shooting auxiliary lever according to claim 8, characterized in that: The slot has an inner wall and an outer wall which are arranged opposite to each other in the radial direction, the inner wall is closer to the inside, and the outer wall is closer to the outside. A third threaded portion which is threadedly connected to the slot is provided on the side of the plug-in portion facing the inner wall, and a glue storage groove is provided on the side of the plug-in portion facing the outer wall. The glue storage groove extends around the circumference of the plug-in portion.

10. The shooting auxiliary lever according to claim 1, characterized in that: The transfer tube has a fourth threaded portion located on its outer ring wall, and the fourth threaded portion is an external thread extending from one end of the transfer tube to the other end of the transfer tube; The outer tube has a plurality of guide strips spaced apart on its inner ring wall, the plurality of guide strips extending in the axial direction of the outer tube and having a fifth threaded portion threadedly connected to the fourth threaded portion; The inner annular wall of the outer tube has a sixth threaded connection portion disposed around the second connecting hole, and the sixth threaded connection portion is threadedly connected to the fourth threaded connection portion.

Images