CN113967899B

CN113967899B - External screw lifting type section bar support

Info

Publication number: CN113967899B
Application number: CN202111331135.2A
Authority: CN
Inventors: 崔鲁彬
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-11-11
Filing date: 2021-11-11
Publication date: 2022-12-09
Anticipated expiration: 2041-11-11
Also published as: CN113967899A

Abstract

The invention discloses an external screw rod lifting type joint rod support, which belongs to the field of supports and comprises a driving main part, a sliding duplex sleeve, a group of duplex tight pipe sleeves, a lifting joint pipe, a locking structure and a limiting structure; the driving main part is driven by a lead screw, two ends of the lead screw are divided into a lead screw polished rod part and a lead screw thread part according to the existence of threads, and the lead screw polished rod part is close to the driving main part; the sliding duplex sleeve bearing is connected to the screw rod and is fixedly connected with the driving main part; can be when the support need extend, stretch out interior joint pipe one by one through the screw thread portion on the lead screw and the cooperation of nut, on the one hand, guaranteed interior joint pipe and stretching out the stability of in-process, on the other hand, can produce the condition of rocking after having avoided the lead screw overlength, solved the lead screw under the condition of fixed length, the problem that the support extending distance is limited has reduced the wasting of resources of lead screw under the prerequisite of guaranteeing lead screw intensity.

Description

External screw lifting type section bar support

Technical Field

The invention relates to the field of supports, in particular to an external screw rod lifting type section rod support.

Background

The bracket is a tool for facilitating the placement of the desired item. In the using process, the support is often adjusted in a manner that the extending length cannot meet the using requirement and is extended or retracted, the support is usually lifted in a lead screw manner, and the extending length of the support is longer, so that the support is easy to shake if the length of the lead screw is too long, and the support is easy to bend due to insufficient supporting strength of the middle part. Meanwhile, the connection mode that the support can realize is single, so that the connection modes of straight line connection, article word connection and square connection cannot be embodied on the same support, and need to be replaced according to the actual situation, which is very inconvenient, and the balance reached by the connection of different structures is different and is difficult to control.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide an outer lead screw lifting type joint rod support, which can be used for extending inner joint pipes one by one through the matching of a lead screw thread part on a lead screw and a nut when the support needs to be extended, so that on one hand, the stability of the inner joint pipes in the extending process is ensured, on the other hand, the situation that the lead screw shakes after being overlong is avoided, the problem that the extending distance of the support is limited under the condition that the lead screw is in a fixed length is solved, and the resource waste of the lead screw is reduced on the premise that the strength of the lead screw is ensured.

In order to solve the above problems, the present invention adopts the following technical solutions.

The external screw rod lifting type joint rod support comprises a driving main part, a sliding duplex sleeve, a group of duplex tight sleeves, a lifting joint pipe, a locking structure and a limiting structure; the driving main part is driven by a lead screw, two ends of the lead screw are divided into a lead screw polished rod part and a lead screw threaded part according to the existence of threads, and the lead screw polished rod part is close to the driving main part; the sliding duplex sleeve bearing is connected to the screw rod, and the sliding duplex sleeve is fixedly connected with the driving main part; the lifting joint pipe comprises an outer joint pipe fixed outside and an inner joint pipe lifted inside, and at least one inner joint pipe is arranged; the group of duplex tight pipe sleeves are arranged in the axial direction of the lifting joint pipe, each group of duplex tight pipe sleeves comprise at least two fixed pipe sleeves and at least two movable pipe sleeves capable of moving along with the inner joint pipe, the fixed pipe sleeves at the bottom ends are fixedly connected to the bottom ends of the outer joint pipes, the fixed pipe sleeves at the top ends are fixedly connected to the top ends of the inner joint pipes in the extending direction, and the movable pipe sleeves are arranged on the outer surface of the lifting joint pipe; the fixed pipe sleeve and the movable pipe sleeve which are fixedly connected to the top end of the inner joint pipe in the extension direction are matched with the threaded part of the screw rod through nuts, when the sliding duplex sleeve moves to the movable pipe sleeve along with the driving main part, the inner joint pipe extends step by step and stretches out under the action of the driving main part, and the radial directions of the middle part and the two end parts of the inner joint pipe are limited through the matching between the limiting structure and the duplex tight pipe sleeve; the locking structures are arranged in the movable pipe sleeve and the sliding duplex pipe sleeve; the limiting structures are arranged on the radial direction of the lifting joint pipes, and the limiting structures are arranged at the two ends and the middle position of each joint pipe.

Furthermore, the driving main part is a motor, and the motor is connected with the screw rod and is close to one end of the sliding duplex sleeve; the motor is fixedly provided with a battery, the battery is electrically connected with the motor, and the outer surface of the battery is provided with a power switch.

Further, an arc-shaped cover is arranged on the outer surface of the fixed pipe sleeve at the top end; the top end of a screw thread part on the screw rod is spherical, and the spherical part is positioned in the arc-shaped cover, so that the screw rod is in contact with a fixed pipe sleeve at the top end to push or the screw rod and the fixed pipe sleeve are separated.

Furthermore, the locking structure comprises a lock catch pin hook, a lock catch limiting groove, a spring and a pipe tightening sleeve groove part; the locking pin hook is arranged in the movable pipe sleeve and the sliding duplex pipe sleeve in a sliding mode, a locking release wrench is fixedly arranged on the end face, located in the sliding duplex pipe sleeve, of the locking pin hook, and the locking release wrench extends out of the sliding duplex pipe sleeve; the lock catch limiting groove is arranged in the side end face of the lock catch pin hook and is positioned in the axial direction of the lifting joint pipe; one end of the spring is connected to the latch pin hook, and the other end of the spring is connected to the side end wall of the movable pipe sleeve or the sliding duplex pipe sleeve; the pipe tightening sleeve groove part is fixedly arranged on the side end face of the movable pipe sleeve in the axial direction and is positioned in the opposite direction with the lock catch limiting groove, and the pipe tightening sleeve groove part and the lock catch limiting groove are matched with each other to limit the separation of the movable pipe sleeve.

Furthermore, a control switch is arranged in the movable pipe sleeve close to the fixed pipe sleeve side; a positive and negative rotation switch is arranged on the end face of the movable pipe sleeve side close to the fixed pipe sleeve side; a stop switch is arranged on the end face of the fixed pipe sleeve at the bottom end, which is close to the side end face of the sliding duplex sleeve; the control switch, the forward and reverse rotation switch and the stop switch are connected with the driving main part through electric signals.

Further, the stop switch is divided into a forward rotation start switch and a reverse rotation start switch.

Furthermore, the limiting structure comprises a pair of main lock pin holes, an auxiliary lock pin hole and a reverse pin hole; the pair of main lock catch pin holes are arranged on the inner joint pipes and are respectively positioned at the bottom end position and the middle part of each inner joint pipe; the auxiliary lock pin hole is arranged on the inner joint pipe and is positioned at the top end of each inner joint pipe; the reverse pin hole is arranged on the outer surface of the outer joint pipe.

Furthermore, the limiting structure further comprises a limiting piece, and the limiting piece is arranged on the inner section pipe and is positioned in the opposite direction of the main lock catch pin hole.

Further, the inner joint pipe comprises a first pipe, a second pipe and a third pipe, wherein the diameters of the first pipe, the second pipe and the third pipe are increased one by one.

Furthermore, tight pipe fittings are arranged on the group of duplex tight pipe sleeves at intervals, and the tight pipe fittings are connected with the outer surface of the outer joint pipe and the outer surface of the inner joint pipe step by step; the pipe tightening piece adopts a pipe tightening screw.

Compared with the prior art, the invention has the advantages that:

1. this scheme is when the support need extend, stretches out interior joint pipe one by one through lead screw thread portion on the lead screw and nut cooperation, on the one hand, has guaranteed interior joint pipe and is stretching out the stability of in-process, and on the other hand can produce the condition of rocking after having avoided the lead screw overlength, has solved the lead screw under the condition of regular length, and the problem that support extending distance is limited has reduced the wasting of resources of lead screw under the prerequisite of guaranteeing lead screw intensity.

2. When the support extends, the movable pipe sleeve is adopted to match with the limiting structure through the locking structure, so that the strength of the extending part is increased, the limit on the middle part of the inner pipe is increased, the strength after the inner pipe is extended is ensured, and the accident that the middle of the inner pipe is broken due to the overlong length of the inner pipe is avoided. Through adopting the lift festival union coupling of multiunit as required, solved a word connection, article word connection and mouth word connection to and guarantee its balance when connecting, its manufacturing approach is simple simultaneously, and required maintenance means is more simple.

3. When the support extends, the inner joint pipe can be extended out only by forward rotation and reverse rotation of the screw rod. When the lead screw corotation, the arc cover on through fixed pipe box contacts with the globular part on the lead screw most advanced, forms and skids, on the one hand, can reduce the friction between lead screw and the fixed pipe box, avoids the direct contact of lead screw most advanced and arc cover, leads to both contact parts to appear damaged easily. On the other hand, the tip of the screw rod is directly covered by the arc cover, and the fixed pipe sleeve and the lifting joint pipe can be pushed out during screw rod transmission without redundant parts. When the screw rod rotates reversely, the screw thread part of the screw rod can sequentially separate the fixed pipe sleeve 21 and the movable pipe sleeve 22 at the top end one by one under the action of the nut, so that the inner joint pipe extends out to prolong the support.

4. In the extension process of the inner-section pipe, the pipe tightening sleeve groove parts on the adjacent movable pipe sleeves are in locking fit with the lock catch limiting grooves in the lock catch pin hooks, so that the lock catch pin hooks can be locked and separated with the main lock catch pin holes and the auxiliary lock catch pins Kong Kuaisu, and the locking and separating modes are simple.

5. This scheme is when the support extends and contracts, whether the start-up and the condition of turning to of motor are controlled through control switch, positive reverse switch and stop switch, need not unnecessary manual control and can extend the support and withdraw to when user self-regulation as required, the accessible presses corotation start switch and the reversal start switch on the stop switch that is closest to the user, controls the extension and the shrink condition of support, convenient operation.

6. This scheme has increased the support intensity of interior nodal pipe after stretching out through ending the position piece, has guaranteed that each in situ nodal pipe can and adjacent interior nodal pipe between the friction after stopping extending, has directly improved the support intensity after interior nodal pipe extends to and the indirect intensity limit that has improved the whole ability of support, guarantee the stable effect of support.

Drawings

FIG. 1 is a schematic front view of the present invention;

FIG. 2 is a schematic view of the structure of the present invention at A;

FIG. 3 is a schematic view of the structure of the present invention at B;

FIG. 4 is a schematic cross-sectional view of FIG. 3 according to the present invention;

FIG. 5 is a schematic view of the structure of the present invention at C;

FIG. 6 is a schematic front view of the first view after the exercise of the present invention;

FIG. 7 is a schematic front view of the present invention at a second perspective after movement;

FIG. 8 is a schematic front view of the present invention at a third viewing angle after movement;

FIG. 9 is a schematic front view of a fourth perspective of the present invention after movement;

FIG. 10 is a schematic front view of the present invention at a fifth perspective after movement;

fig. 11 is a front view of the sixth view after the exercise of the present invention.

The numbering in the figures illustrates:

the locking device comprises a driving main part 1, a locking release wrench 10, a battery 11, a motor 12, a screw 13, a sliding duplex sleeve 14, a duplex locking sleeve 2, a fixed sleeve 21, an arc cover 211, a movable sleeve 22, a tube tightening part 3, a lifting joint tube 4, a first tube 41, a second tube 42, a third tube 43, an outer joint tube 44, a locking structure 5, a locking pin hook 51, a locking limit groove 511, a spring 52, a tube tightening sleeve groove part 53, a control switch 6, a forward and reverse switch 7, a stop switch 8, a limit structure 9, a main locking pin hole 91, a stop piece 92, an auxiliary locking pin hole 93 and a reverse pin hole 94.

Detailed Description

Referring to fig. 1-11, the external lead screw lifting type section bar support comprises a driving main part 1, a sliding duplex sleeve 14, a group of duplex tightening pipe sleeves 2, a lifting section bar 4, a locking structure 5 and a limiting structure 9; the driving main part 1 is driven by a lead screw 13, two ends of the lead screw 13 are divided into a lead screw polished rod part and a lead screw threaded part according to the existence of threads, and the lead screw polished rod part is close to the driving main part 1; the sliding duplex sleeve 14 is connected to the lead screw 13 through a bearing, and the sliding duplex sleeve 14 is fixedly connected with the driving main part 1; the lifting joint pipe 4 comprises an outer joint pipe 44 fixed outside and an inner joint pipe lifted inside, and at least one inner joint pipe is arranged; the group of duplex tight pipe sleeves 2 are arranged in the axial direction of the lifting joint pipe 4, the group of duplex tight pipe sleeves 2 comprises at least two fixed pipe sleeves 21 and at least two movable pipe sleeves 22 capable of moving along with the inner joint pipe, the fixed pipe sleeve 21 at the bottom end is fixedly connected to the bottom end of the outer joint pipe 44, the fixed pipe sleeve 21 at the top end is fixedly connected to the top end of the extension direction of the inner joint pipe, the extension direction and the retraction direction of the inner joint pipe respectively point to the bottom end at the top end, and the movable pipe sleeves 22 are arranged on the outer surface of the lifting joint pipe 4; the fixed pipe sleeve 21 and the movable pipe sleeve 22 which are fixedly connected to the top end of the inner joint pipe in the extension direction are matched with the threaded part of the screw rod through nuts, when the sliding duplex sleeve 14 moves to the position of the movable pipe sleeve 22 along with the driving main part 1, the inner joint pipe is extended step by step and extended out under the action of the driving main part 1, and the radial directions of the middle part and the two end parts of the inner joint pipe are limited through the matching between the limiting structure 9 and the duplex tight pipe sleeve 2; the locking structures 5 are arranged in the movable pipe sleeve 22 and the sliding duplex pipe sleeve 14; the limiting structures 9 are arranged on the radial direction of the lifting joint pipes 4, and the limiting structures 9 are arranged at the two ends and the middle position of each joint pipe. The group of duplex tight pipe sleeves 2 are provided with tight pipe fittings 3 at intervals, and the tight pipe fittings 3 are connected with the outer surface of the outer joint pipe 44 and the outer surface of the inner joint pipe step by step; the pipe tightening piece 3 adopts a pipe tightening screw. The inner joint pipe comprises a first pipe 41, a second pipe 42 and a third pipe 43 which are increased in diameter one by one.

Referring to fig. 1, the driving main part 1 is a motor 12, the motor 12 is connected to a lead screw 13 and is close to one end of the sliding duplex sleeve 14; the motor 12 is fixedly provided with a battery 11, the battery 11 is electrically connected with the motor 12, a power switch is arranged on the outer surface of the battery 11, and the power switch controls the motor 12 to operate.

Referring to fig. 5, an arc cover 211 is disposed on the outer surface of the fixed pipe sleeve 21; the top end of the screw thread part on the screw 13 is spherical, and the spherical part is positioned in the arc-shaped cover 211, so that the screw 13 is contacted with and pushed by the fixed pipe sleeve 21 at the top end or the fixed pipe sleeve 21 at the top end is separated from the fixed pipe sleeve.

Referring to fig. 2, the locking structure 5 includes a locking pin hook 51, a locking limiting groove 511, a spring 52 and a pipe tightening sleeve groove 53; the locking pin hook 51 is arranged in the movable pipe sleeve 22 and the sliding duplex sleeve 14 in a sliding manner, the side end face, positioned in the sliding duplex sleeve 14, of the locking pin hook 51 is fixedly provided with the unlocking wrench 10, and the unlocking wrench 10 extends out of the sliding duplex sleeve 14; the lock catch limiting groove 511 is arranged in the side end face of the lock catch pin hook 51 and is positioned in the axial direction of the lifting joint pipe 4; one end of the spring 52 is connected to the latch pin hook 51, and the other end is connected to the movable pipe sleeve 22 or the side end wall of the sliding duplex pipe sleeve 14, and the spring 52 is in an elastic compression state; the pipe tightening sleeve groove part 53 is fixedly arranged on the side end surface of the movable pipe sleeve 22 in the axial direction, and is positioned in the opposite direction to the lock catch limiting groove 511, and the pipe tightening sleeve groove part 53 and the lock catch limiting groove 511 are matched with each other to limit the separation of the movable pipe sleeve 22.

Referring to fig. 5-6, a control switch 6 is disposed in the movable pipe sleeve 22 near the fixed pipe sleeve 21; a positive and negative rotation switch 7 is arranged on the end face of the movable pipe sleeve 22 close to the fixed pipe sleeve 21; a stop switch 8 is arranged on the end face of the fixed pipe sleeve 21 at the bottom end, which is close to the side end face of the sliding duplex sleeve 14; the control switch 6, the forward and reverse rotation switch 7 and the stop switch 8 are in electric signal connection with the driving main part 1. The stop switch 8 is divided into a forward rotation start switch and a reverse rotation start switch.

Referring to fig. 5-6, the limiting structure 9 includes a pair of primary locking pin holes 91, secondary locking pin holes 93 and reverse pin holes 94; the pair of main lock pin holes 91 are arranged on the inner joint pipes and are respectively positioned at the bottom end and the middle part of each layer of inner joint pipe; the auxiliary lock pin hole 93 is arranged on the inner joint pipe and is positioned at the top end of each inner joint pipe; a reverse pin hole 94 is provided in the outer joint tube outer surface. The position limiting structure 9 further comprises a position limiting sheet 92, and the position limiting sheet 92 is arranged on the inner tube section and is located in the opposite direction of the main lock catch pin hole 91.

When the bracket needs to be extended, a user can press a power switch on the battery 11 to enable the motor 12 to be started, the lead screw 13 generates positive rotation, the motor 12 and the sliding duplex sleeve 14 can move in the axial direction through transmission between the threaded part of the lead screw and the nut, and meanwhile, the spherical part at the tip of the lead screw 13 can provide force required by movement for the fixed sleeve 21 close to the threaded part side of the lead screw through contact with the arc-shaped cover 211, so that the fixed sleeve 21 close to the threaded part side of the lead screw is driven to move away from the fixed sleeve 21 close to the polished rod part side of the lead screw.

Meanwhile, in the moving process of the fixed pipe sleeve 21 close to the screw thread part side of the screw rod, the first pipe 41 is driven to move, so that the first pipe 41 extends out of the outer joint pipe 44, when the latch pin hook 51 in the movable pipe sleeve 22 at the outermost end is contacted with the main latch pin hole 91 at the middle part of the first pipe 41, the latch pin hook 51 is promoted to be separated from the adjacent pipe tightening sleeve groove part 53 under the elastic restoring action of the spring 52, until the latch pin hook 51 is embedded into the main latch pin hole 91, so as to increase the strength of the middle part of the first pipe 41, and then the movable pipe sleeve 22 at the outermost end moves along with the first pipe 41 in the same direction, when the first pipe 41 moves to a position where the main lock pin hole 91 near the side of the feed screw polished rod portion is close to the movable pipe sleeve 22 at the adjacent side, the main lock pin hole 91 on the first pipe 41 near the side of the feed screw polished rod portion coincides with the auxiliary lock pin hole 93 on the second pipe 42, so that the next auxiliary lock pin hook 51 is embedded into the main lock pin hole 91 on the first pipe 41 near the side of the feed screw polished rod portion and the auxiliary lock pin hole 93 on the second pipe 42 under the action of spring return 52, through the auxiliary lock pin hole 93 on the second pipe 42 and the main lock pin hole 91 on the first pipe 41 near the side of the feed screw polished rod portion, and the lock pin hook 51 is simultaneously connected to the first pipe 41 and the second pipe 42, so that the second pipe 42 can move.

Just before the second tube 42 moves, the sliding duplex sleeve 14 abuts against the forward and reverse rotation switch 7 by moving on the outer joint tube 44, and the locking pin hook 51 in the sliding duplex sleeve 14 is embedded into the reverse rotation pin hole 94 under the action of the elastic force recovery of the spring 52, so that the positioning and the pause movement of the sliding duplex sleeve 14 are realized, meanwhile, under the condition that the forward and reverse rotation switch 7 is pressed, the forward and reverse rotation switch 7 controls the motor 12 to rotate reversely, because the lead screw 13 pauses to move, under the action of the nut, the next group of movable sleeves 22 moves along with the second tube 42, and the lead screw is separated from the fixed sleeve 21 close to the thread side of the lead screw, so that the second tube 42 is led with the first tube 41 to extend together.

Then, the above steps are repeated, the second tube 42 and the third tube 43 are extended step by step, when the latch pin hook 51 in the movable pipe sleeve 22 near the side of the feed screw rod portion is embedded in the main latch pin hole 91 near the side of the feed screw rod portion in the third tube 43, the latch pin hook 51 is not contacted with the control switch 6, so that the control switch 6 controls the motor 12 to stop.

When the bracket needs to be retracted, a user can press the stop switch 8 to start the motor 12, and the steps are repeated in the reverse direction, so that the third tube 43, the second tube 42 and the first tube 41 are retracted into the outer joint tube 44 one by one, when the bracket is retracted to the state shown in fig. 7, the user manually pulls the unlocking wrench 10 to move, so that the locking pin hook 51 in the sliding duplex tube 14 is separated from the reverse pin hole 94, so that the sliding duplex tube 14 is urged to contact with the stop switch 8 under the action of the motor 12 and the lead screw 13, and the stop switch 8 controls the motor 12 to stop.

Claims

1. Outer screw over-and-under type festival pole support, its characterized in that: the device comprises a driving main part (1), a sliding duplex sleeve (14), a group of duplex tight sleeves (2), a lifting joint pipe (4), a locking structure (5) and a limiting structure (9); the driving main part (1) is driven by a lead screw (13), two ends of the lead screw (13) are divided into a lead screw polished rod part and a lead screw thread part, and the lead screw polished rod part is close to the driving main part (1);

the sliding duplex sleeve (14) is connected to the screw rod (13) through a bearing, and the sliding duplex sleeve (14) is fixedly connected with the driving main part (1); the lifting joint pipe (4) comprises an outer joint pipe (44) fixed outside and an inner joint pipe lifted inside, and at least one inner joint pipe is arranged;

a group of duplex tight pipe sleeves (2) are arranged in the axial direction of the lifting joint pipe (4), the group of duplex tight pipe sleeves (2) comprises at least two fixed pipe sleeves (21) and at least two movable pipe sleeves (22) capable of moving along with the inner joint pipe, the fixed pipe sleeves (21) at the bottom end are fixedly connected to the bottom end of the outer joint pipe (44), the fixed pipe sleeves (21) at the top end are fixedly connected to the top end of the inner joint pipe in the extending direction, and the movable pipe sleeves (22) are arranged on the outer surface of the lifting joint pipe (4); the fixed pipe sleeve (21) and the movable pipe sleeve (22) at the top end are matched with the threaded part of the screw rod through nuts, when the sliding duplex sleeve (14) moves to the position of the movable pipe sleeve (22) along with the driving main part (1), the inner joint pipe extends step by step and extends out under the action of the driving main part (1), and the radial directions of the middle part and the two end parts of the inner joint pipe are limited through the matching between the limiting structure (9) and the duplex tight pipe sleeve (2);

the locking structures (5) are arranged in the movable pipe sleeve (22) and the sliding duplex sleeve (14); the limiting structures (9) are arranged on the radial direction of the lifting joint pipes (4), and the limiting structures (9) are arranged at the two ends and the middle position of each joint pipe.

2. The external screw rod lifting type section bar support according to claim 1, wherein: the driving main part (1) is a motor (12), and the motor (12) is connected with a lead screw (13) and is close to one end of the side of the sliding duplex sleeve (14);

the motor (12) is fixedly provided with a battery (11), the battery (11) is electrically connected with the motor (12), and the outer surface of the battery (11) is provided with a power switch.

3. The external screw rod lifting type section bar support according to claim 1, wherein: the outer surface of the fixed pipe sleeve (21) at the top end is provided with an arc cover (211); the top end of a screw thread part on the screw (13) is spherical, and the spherical part is positioned in the arc-shaped cover (211) so that the screw (13) can be contacted with and pushed by a fixed pipe sleeve (21) at the top end or the screw and the fixed pipe sleeve are separated.

4. The external screw rod lifting type section bar support according to claim 1, wherein: the locking structure (5) comprises a locking pin hook (51), a locking limiting groove (511), a spring (52) and a pipe tightening sleeve groove part (53);

the locking pin hook (51) is arranged in the movable pipe sleeve (22) and the sliding duplex sleeve (14) in a sliding mode, a side end face, located in the sliding duplex sleeve (14), of the locking pin hook (51) is fixedly provided with a locking release wrench (10), and the locking release wrench (10) extends out of the sliding duplex sleeve (14);

the lock catch limiting groove (511) is arranged in the side end face of the lock catch pin hook (51) and is positioned in the axial direction of the lifting joint pipe (4);

one end of the spring (52) is connected to the locking pin hook (51), and the other end is connected to the side end wall of the movable pipe sleeve (22) or the sliding duplex pipe sleeve (14);

the pipe tightening sleeve groove part (53) is fixedly arranged on the side end surface of the movable pipe sleeve (22) in the axial direction and is positioned in the opposite direction with the lock catch limiting groove (511), and the pipe tightening sleeve groove part (53) is matched with the lock catch limiting groove (511) to limit the separation of the movable pipe sleeve (22).

5. The external lead screw lifting type section bar support as claimed in claim 1, wherein: a control switch (6) is arranged in the movable pipe sleeve (22) close to the fixed pipe sleeve (21); a positive and negative rotation switch (7) is arranged on the end face of the movable pipe sleeve (22) close to the fixed pipe sleeve (21); a stop switch (8) is arranged on the end face of the fixed pipe sleeve (21) at the bottom end, which is close to the side end face of the sliding duplex sleeve (14); the control switch (6), the forward and reverse rotation switch (7) and the stop switch (8) are in electric signal connection with the driving main part (1).

6. The external screw rod lifting type joint rod support frame according to claim 5, wherein: the stop switch (8) is divided into a forward rotation start switch and a reverse rotation start switch.

7. The external screw rod lifting type section bar support according to claim 1, wherein: the limiting structure (9) comprises a pair of main lock catch pin holes (91), an auxiliary lock catch pin hole (93) and a reverse pin hole (94);

a pair of main lock catch pin holes (91) are formed in the inner joint pipes and are respectively located at the bottom end and the middle part of each inner joint pipe;

the auxiliary lock catch pin hole (93) is arranged on the inner joint pipe and is positioned at the top end of each inner joint pipe;

the reverse pin hole (94) is arranged on the outer surface of the outer joint pipe.

8. The external lead screw lifting type section bar support as claimed in claim 7, wherein: the limiting structure (9) further comprises a stopping sheet (92), and the stopping sheet (92) is arranged on the inner joint pipe and is positioned in the opposite direction of the main lock catch pin hole (91).

9. The external screw rod lifting type section bar support according to claim 1, wherein: the inner joint pipe comprises a first pipe (41), a second pipe (42) and a third pipe (43) which are increased in diameter one by one.

10. The external screw rod lifting type section bar support according to claim 1, wherein: the tight pipe fittings (3) are arranged on the group of the duplex tight pipe sleeves (2) at intervals, and the tight pipe fittings (3) are connected with the outer joint pipe (44) and the outer surface of the inner joint pipe step by step.