CN211169644U

CN211169644U - Automatic tightening winch

Info

Publication number: CN211169644U
Application number: CN201921928549.1U
Authority: CN
Inventors: 李忠伴
Original assignee: Taizhou Volla Fire Fighting Equipment Co ltd
Current assignee: Taizhou Volla Fire Fighting Equipment Co ltd
Priority date: 2019-11-09
Filing date: 2019-11-09
Publication date: 2020-08-04
Anticipated expiration: 2029-11-09

Abstract

The utility model discloses an automatic shrink capstan winch relates to capstan winch technical field, and its technical scheme main points are: the winch comprises a mounting frame, a motor and a winch barrel, wherein a rope is wound on the winch barrel, a traction main body is arranged on the mounting frame, a movable mechanism and a pressing piece are arranged on the traction main body, the movable mechanism comprises a roller and a driving piece, the roller is rotatably connected in the traction main body, the driving piece is arranged on the traction main body, the rope penetrates through the roller and the pressing piece, and the driving piece is used for driving the roller to be close to or far away from the pressing piece. The motor drives the winding drum to rotate, so that the recovery of the rope is realized; when the driving part on the traction main body drives the roller to be close to the pressing part, the rope is pressed by the pressing part and the roller, the rope between the traction main body and the winding drum is always kept in tension, and the recovered rope can be tightly coiled on the winding drum, so that the purpose of conveniently coiling the rope tightly on the winding drum is realized.

Description

Automatic tightening winch

Technical Field

The utility model relates to a capstan winch technical field, in particular to automatic crimple capstan winch.

Background

The winch is mainly used for self-protection and traction devices of off-road vehicles, agricultural vehicles, yachts and other special vehicles. When traction operation, rescue and field self rescue are needed, the electric winch plays a great role.

At present, chinese patent publication No. CN201942458U discloses an electric winch. The air pump type winch comprises an air pump, a motor, a speed reducer, a winch drum and a transmission mechanism, wherein the input end of the transmission mechanism is connected with an output shaft of the motor, the output end of the transmission mechanism is located on the side face of the motor, and the output end of the transmission mechanism is connected with the input shaft of the air pump.

The technical scheme has the following defects: the cable is wound on the winding drum, the cable is separated from the winding drum to be sequentially discharged when the cable is discharged, after the cable is used, the winding drum needs to be driven by the motor to rotate, so that the cable is wound back to the winding drum, in order to ensure that the cable can be tightly wound on the winding drum, a user needs to hold the cable and apply pressure to the cable far away from one side of the winding drum, the cable is tensioned, and great inconvenience is brought to the user in the process.

And in the process of retracting the rope to the winding drum, the rope cannot be tightened because the rope has no tension, and the rope which is not tightened is directly wound back to the winding drum, so that the rope is easy to loosen. The rope wound in this way is not tight, and the service life of the rope is seriously affected.

SUMMERY OF THE UTILITY MODEL

Not enough to prior art exists, the utility model aims to provide an automatic crimple capstan winch, it has can be comparatively convenient with the inseparable dish of hank rope advantage on a hoist section of thick bamboo.

The above technical purpose of the present invention can be achieved by the following technical solutions: the winch comprises a mounting frame and a motor arranged on one side of the mounting frame, wherein an output shaft of the motor penetrates through the mounting frame and a winch barrel fixedly connected with the mounting frame, a rope is wound on the winch barrel, a traction main body is arranged on the mounting frame, a movable mechanism and a pressing piece are arranged on the traction main body, the movable mechanism comprises a roller and a driving piece, the roller is rotatably connected in the traction main body, the driving piece is arranged on the traction main body, the rope penetrates through the roller and the pressing piece, and the driving piece is used for driving the roller to be close to or far away from the pressing piece.

Through the technical scheme, the motor drives the winding drum on the output shaft of the motor to rotate, so that the recovery of the rope is realized; the traction main body is arranged on the mounting frame, when the driving piece on the traction main body drives the roller to be close to the pressing piece, the rope is pressed by the pressing piece and the roller, in the process that the rope is driven by the winding drum to be recovered, the tension is always kept on the rope between the traction main body and the winding drum, and the recovered rope can be tightly coiled on the winding drum, so that the aim of conveniently coiling the rope tightly on the winding drum is fulfilled; in the process that the driving piece drives the roller to be far away from the pressing piece, the gap between the pressing piece and the roller is increased, and the rope on the winding drum can more easily penetrate between the pressing piece and the roller, so that the rope can be conveniently released from the winding drum.

Preferably, a support is fixedly connected to the mounting frame, a sliding rod for the traction main body to slide is arranged on the support, at least two sliding rods are arranged on the sliding rod and are parallel to the hoisting drum, and the traction main body can slide along the axial direction of the sliding rod.

Through the technical scheme, the traction main body slides on the slide bar, so that the rope between the traction main body and the winding drum can be always perpendicular to the winding drum, and the rope is not easy to wind in one position in the process of recovering the rope by the winding drum.

Preferably, the central axis of the roller is parallel to the central axis of the winding drum, and a groove for accommodating the peripheral wall of the cable is concavely formed on the peripheral wall of the roller.

Through above-mentioned technical scheme, the recess on the gyro wheel is used for supporting the noose, and the in-process of noose motion, and the noose drives the gyro wheel and rotates, guarantees that the noose can not break away from the gyro wheel.

Preferably, the outer wall of the sliding rod is provided with a fixing sleeve, the fixing sleeve is fixedly connected inside the traction main body, and the fixing sleeve slides on the outer wall of the sliding rod.

Through above-mentioned technical scheme, fixed cover is fixed with the main part of pulling, pulls the main part alright drive fixed cover and slides in the slide bar outer wall, has avoided pulling main part and slide bar outer wall direct contact, and slide bar or fixed cover damage back only need change slide bar or fixed cover, and need not change whole capstan winch.

Preferably, the compressing part comprises an upper movable wheel and a lower movable wheel, the upper movable wheel and the lower movable wheel are respectively sleeved with two outer walls of the fixed sleeve, the central axis of the upper movable wheel and the central axis of the lower movable wheel are both parallel to the central axis of the roller, the cable passes through the position between the upper movable wheel and the lower movable wheel, and the cable is located between the roller and one of the roller and the movable wheel.

Through the technical scheme, the cable penetrates between the two movable wheels, the shifting block drives the idler wheel to tightly press the cable on the outer wall of the upper movable wheel or the outer wall of the lower movable wheel, so that the cable can be tightly coiled on the winding drum in the process of retracting the cable by the winding drum.

Preferably, movable blocks are symmetrically arranged on two sides of the traction main body, guide holes I are formed in the movable blocks, guide posts I are arranged in the guide holes I, and the guide posts I are fixedly connected to the traction main body; draw the main part both sides and all seted up guiding hole two, the gliding is connected with guide post two in the guiding hole two, the gyro wheel rotate connect in guide post two, just guide post two fixed connection in the movable block.

Through above-mentioned technical scheme, driving piece drive movable block slides along guiding hole one and two directions of guiding hole, and the gliding in-process of movable block, guide post two and gyro wheel slide along with the movable block, and then change the interval of gyro wheel and last loose pulley or lower loose pulley.

Preferably, the driving piece includes shifting block and air spring, the shifting block articulate in pull the main part, just be formed with the extrusion section on the shifting block, the extrusion section is used for contradicting the movable block and right the movable block is applyed with decurrent pressure, the air spring set up in pull the main part with between the movable block, just the air spring is used for right the movable block is applyed with ascending elasticity.

According to the technical scheme, the shifting block is hinged to the traction main body, the shifting block can press the movable block downwards conveniently through the extrusion section, so that the distance between the roller and the upper movable wheel is increased, and meanwhile, the distance between the roller and the lower movable wheel is reduced; after the limit of the shifting block is lost, the air spring applies upward elastic force to the movable block, so that the movable block moves upwards, the distance between the roller and the upper movable wheel is further reduced, and the distance between the roller and the lower movable wheel is increased; no matter the cable is positioned between the roller wheel and the upper movable wheel or between the roller wheel and the lower movable wheel, the adjusting shifting block can compress or release the cable.

Preferably, both sides of the traction main body are provided with return springs, the return springs are sleeved on the sliding rod, one ends of the return springs are abutted against the support, and the other ends of the return springs are abutted against the traction main body.

Through the technical scheme, the reset springs on the two sides of the traction main body can effectively ensure that the traction main body slides back and forth at a constant speed in the process of sliding the traction main body.

Preferably, the rope guider is arranged on the mounting frame and used for uniformly winding the rope on the hoisting drum, and comprises a fixing plate arranged on the mounting frame, a rope guide frame hinged on the fixing plate, a rope guide rod arranged on the rope guide frame and used for supporting the rope, and a control cylinder fixedly connected to the fixing plate, wherein the rope guide rod is rotatably connected to the rope guide frame, and the control cylinder drives the rope guide rod to be tightly attached to the rope on the hoisting drum.

Through the technical scheme, the rope guide frame is hinged to the fixing plate, the rope guide rod is connected to the rope guide frame in a rotating mode, the control cylinder on the fixing plate drives the rope guide frame to move downwards, one end, provided with the rope guide rod, of the rope guide frame is tilted and tightly attached to the rope winch on the rope winch barrel, the rope winch on the rope winch barrel is tightly attached to the rope winch barrel, the rope guide rod is used for supporting the rope winch and rotates along with the movement of the rope winch, and excessive abrasion of the rope winch and the rope guide rod is avoided.

Preferably, the traction main body is provided with at least two rotating rollers, and a limiting space for the rope to pass through is formed between the rotating rollers.

Through the technical scheme, the limit space effectively ensures the retracting direction of the rope, and the rope can rotate along with the rotating roller when the rope touches the rotating roller in the retracting process of the rope, so that excessive friction between the rope and the rotating roller is avoided.

To sum up, the utility model discloses the beneficial effect who contrasts in prior art does: in the process of recovering the rope, the rope can be tightly coiled on the winding drum, and the recovery effect of the rope is good; the friction between the rope and the traction main body is small; the use is more convenient.

Drawings

FIG. 1 is a schematic external structural view of an embodiment;

FIG. 2 is a schematic structural diagram of an exemplary box rolling cylinder;

FIG. 3 is an external view of the traction body in the embodiment;

FIG. 4 is a schematic view of the internal mechanism of the traction body in the embodiment;

FIG. 5 is a schematic structural view of one side of the traction body in the embodiment;

FIG. 6 is a schematic structural view of a rotating roller in the embodiment;

FIG. 7 is an exploded view of the tow body of the example;

FIG. 8 is a bottom view of the embodiment;

fig. 9 is a schematic structural diagram of the rope guide in the embodiment.

Reference numerals: 1. a mounting frame; 11. a support; 111. a slide bar; 112. a limiting member; 1111. fixing a sleeve; 2. a motor; 3. a hoisting drum; 4. a rope is twisted; 5. a traction body; 51. a movable mechanism; 511. a roller; 5111. a groove; 512. a drive member; 5121. shifting blocks; 5122. a gas spring; 5123. an extrusion section; 52. a compression member; 521. an upper movable wheel; 522. a lower movable wheel; 53. a movable block; 531. a first guide hole; 5311. a first guide post; 54. a second guide hole; 541. a second guide post; 55. a rotating roller; 551. a limiting space; 56. an inner cavity; 6. a return spring; 7. a rope guide; 71. a fixing plate; 72. a rope guide frame; 73. a rope guide rod; 74. and (4) controlling the cylinder.

Detailed Description

In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention.

The present invention will be described in further detail with reference to the accompanying drawings.

An automatic tightening winch is shown in figures 1 to 9 and comprises an installation frame 1 and a motor 2 arranged on one side of the installation frame 1, wherein an output shaft of the motor 2 penetrates through the installation frame 1 and is fixedly connected with a winch drum 3, an output shaft of the motor 2 can drive the winch drum 3 to rotate, and a rope 4 is wound on the winch drum 3.

The mounting frame 1 is provided with a traction main body 5, preferably, the mounting frame 1 is fixedly connected with a support 11, the support 11 is provided with a slide bar 111, and the slide bar 111 is provided with at least two slide bars which are parallel to the winding drum 3; the outer wall of the sliding rod 111 is provided with a fixed sleeve 1111, the fixed sleeve 1111 is fixedly connected inside the traction main body 5, and the fixed sleeve 1111 slides on the outer wall of the sliding rod 111. Preferably, the pulling body 5 is fixedly connected to the outer wall of the fixing sleeve 1111, and the pulling body 5 can slide along the axial direction of the sliding rod 111 following the fixing sleeve 1111. Preferably, the length of the sliding rod 111 is equal to the length of the winding drum 3, alternatively, the length of the sliding rod 111 is greater than the length of the winding drum 3, and when the length of the sliding rod 111 is greater than the length of the winding drum 3, the bracket 11 may be provided with a limiting member 112, the limiting member 112 includes a bolt, the limiting member 112 limits the traction main body 5, so as to ensure that the sliding length of the traction main body 5 along the sliding rod 111 is equal to the length of the winding drum 3, and avoid that the sliding distance of the traction main body 5 is too far, so that too many winding turns of the rope 4 are formed at two ends of the winding drum 3, and the problem that the rope 4 cannot be uniformly wound.

An inner cavity 56 is formed in the traction main body 5 in a hollow mode, a movable mechanism 51 and a pressing piece 52 are arranged on the traction main body 5, the movable mechanism 51 comprises a roller 511 and a driving piece 512, the roller 511 is connected into the traction main body 5 in a rotating mode, the central axis of the roller 511 is parallel to the central axis of the winding drum 3, and a groove 5111 for accommodating the outer peripheral wall of the rope 4 is formed in the outer peripheral wall of the roller 511 in a concave mode; the driving member 512 is disposed on the traction body 5, the cable 4 passes between the roller 511 and the pressing member 52, and the driving member 512 is used for driving the roller 511 to approach or separate from the pressing member 52.

The pressing member 52 comprises an upper movable wheel 521 and a lower movable wheel 522, the upper movable wheel 521 and the lower movable wheel 522 are both cylindrical, the upper movable wheel 521 and the lower movable wheel 522 are respectively sleeved on the outer walls of the two fixed sleeves 1111, the central axes of the upper movable wheel 521 and the lower movable wheel 522 are both parallel to the central axis of the roller 511, the cable 4 passes through the space between the upper movable wheel 521 and the lower movable wheel 522, and the cable 4 is located between the roller 511 and one of the movable wheels. When the hoist cable 4 is positioned between the roller 511 and the upper movable wheel 521, the driving element 512 drives the roller 511 to move upwards so as to compress the hoist cable 4, the motor 2 drives the hoisting drum 3 to recover the hoist cable 4, and the recovered hoist cable 4 can be tightly wound on the hoisting drum 3; when the rope 4 is located between the roller 511 and the lower movable wheel 522, the driving element 512 drives the roller 511 to move downwards so as to press the rope 4 tightly, the motor 2 drives the winding drum 3 to rotate, and the rope 4 can be tightly wound on the winding drum 3 after being recovered.

The two sides of the traction main body 5 are symmetrically provided with movable blocks 53, the movable blocks 53 are respectively provided with a first guide hole 531, a first guide post 5311 is arranged in the first guide hole 531, the first guide post 5311 is fixedly connected to the traction main body 5, preferably, the first guide post 5311 comprises a bolt, and the first guide post 5311 is connected to the side wall of the traction main body 5 through the bolt; two guide holes 54 are formed in two sides of the traction main body 5, preferably, the two guide holes 54 comprise kidney-shaped holes, two guide posts 541 are connected in the two guide holes 54 in a sliding mode, the roller 511 is connected to the two guide posts 541 in a rotating mode, the two guide posts 541 are fixedly connected to the movable blocks 53, and preferably, the two guide posts 541 are fixed between the two movable blocks 53 through screws.

The driving member 512 comprises a shifting block 5121 and a gas spring 5122, the shifting block 5121 is hinged to the upper end of the traction main body 5, an arc-shaped extrusion section 5123 is formed on the shifting block 5121, the extrusion section 5123 is used for abutting against the movable block 53 and applying downward pressure to the movable block 53, the gas spring 5122 is arranged between the traction main body 5 and the movable block 53, preferably, one end of the gas spring 5122 is in threaded connection with the movable block 53, the other end of the gas spring 5122 is in threaded connection with the side wall of the traction main body 5, and the gas spring 5122 is used for applying upward elastic force to the movable block 53.

The two sides of the traction main body 5 are both provided with a return spring 6, the return spring 6 is sleeved on the sliding rod 111, one end of the return spring 6 abuts against the support 11, and the other end of the return spring 6 abuts against the traction main body 5. The traction body 5 is provided with at least two rotating rollers 55, a limit space 551 for the rope 4 to pass through is formed between the rotating rollers 55, and the rotating rollers 55 are arranged on the side far away from the roller 511.

The mounting frame 1 is also provided with a rope guider 7, the rope guider 7 is used for winding the rope 4 on the winding drum 3 evenly, the rope guider 7 comprises a fixing plate 71 fixed on the mounting frame 1, a rope guide frame 72 hinged on the fixing plate 71, a rope guide rod 73 arranged on the rope guide frame 72, a control cylinder 74 arranged on the fixing plate 71, the rope guide rod 73 is rotationally connected with the rope guide frame 72, and the rope guide 73 is arranged far away from the fixed plate 71 to ensure that the rope 4 slides on the outer peripheral wall of the rope guide 73 in the process of winding and unwinding the rope 4, the rope guide frame 72 is positioned below the winding drum 3, the output shaft of the control cylinder 74 is connected with the rope guide frame 72, and the control cylinder 74 applies a downward force to the rope guide 72, the end of the rope guide 72 with the rope guide 73 is tilted upward, the peripheral wall of the rope guide rod 73 is tightly attached to the rope 4 on the winding drum 3, and the rope 4 can be sequentially wound on the winding drum 3 in the process of withdrawing the rope 4.

The specific working mode of the automatic tightening winch is as follows:

leading out the rope end of the rope 4 from the winding drum 3, enabling the rope 4 to pass through the upper part of the rope guide rod 73, supporting the rope 4 by the rope guide rod 73, lifting the shifting block 5121 at the moment, enabling the shifting block 5121 to drive the movable block 53 to move downwards, enabling the rope 4 to pass through the space between the roller 511 and the upper movable wheel 521, enabling the rope 4 to be placed in the groove 5111 on the roller 511, enabling the rope 4 to pass through the space between the upper movable wheel 521 and the lower movable wheel 522, supporting the rope 4 by the lower movable wheel 522, enabling the rope 4 to pass through the limiting space 551 between the two rotating rollers 55, enabling the rope 4 to touch the rotating rollers 55 in the process of separating from the winding drum 3, and enabling the rotating rollers 55 to rotate along with the moving direction of the rope 4.

After the rope 4 is used up, the output shaft of the motor 2 drives the winding drum 3 to rotate, so that the recovery of the rope 4 is realized; the control cylinder 74 always applies a downward force to the rope guide frame 72, so that one end of the rope guide frame 72, which is provided with the rope guide rod 73, is tilted and tightly abuts against the ropes 4 coiled on the surface of the winding drum 3, and the recovered ropes 4 are orderly and uniformly coiled on the surface of the winding drum 3. Before the rope 4 is recovered, the shifting block 5121 is pressed downwards, so that the gas spring 5122 acts on the movable block 53, the movable block 53 drives the roller 511 to move towards the upper movable wheel 521, finally, the rope 4 between the roller 511 and the upper movable wheel 521 is pressed tightly, at the moment, the rope 4 between the traction main body 5 and the winding drum 3 is tightened, after the motor 2 works, the winding drum 3 recovers the rope 4, the rope 4 recovered by the winding drum 3 is sequentially distributed on the surface of the winding drum 3 because the rope guide rod 73 is abutted against the rope 4 wound on the surface of the winding drum 3, the rope 4 can drive the traction main body 5 to slide along the direction of the slide rod 111, the elastic force of the reset springs 6 at the two sides of the traction main body 5 acts on the traction main body 5 to ensure that the traction main body 5 slides on the peripheral wall of the slide rod 111 at a constant speed, after the traction main body 5 slides to the end part of the slide rod 111, the side wall of the traction main body 5 with the, the traction main body 5 slides back, the rope 4 is always vertical to the winding drum 3 in the process, and the recovered rope 4 can be tightly and uniformly coiled on the surface of the winding drum 3.

The above description is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention, which is defined by the appended claims.

Claims

1. The utility model provides an automatic shrink capstan winch, includes mounting bracket (1), sets up in motor (2) of mounting bracket (1) one side, motor (2) output shaft runs through mounting bracket (1) and fixedly connected with hoist section of thick bamboo (3), the winding has cable (4), characterized by on hoist section of thick bamboo (3): be provided with on mounting bracket (1) and pull main part (5), it is provided with movable mechanism (51) and compresses tightly piece (52) to pull on main part (5), movable mechanism (51) include gyro wheel (511), driving piece (512), gyro wheel (511) rotate connect in pull in main part (5), driving piece (512) set up in pull on main part (5), noose (4) pass gyro wheel (511) with compress tightly between piece (52), driving piece (512) are used for the drive gyro wheel (511) are close to or keep away from compress tightly piece (52).

2. The automatic retraction winch of claim 1, wherein: the traction device is characterized in that a support (11) is fixedly connected to the mounting rack (1), a sliding rod (111) for the traction main body (5) to slide is arranged on the support (11), at least two sliding rods (111) are arranged on the sliding rod (111) and are parallel to the hoisting drum (3), and the traction main body (5) can slide along the axial direction of the sliding rod (111).

3. The automatic retraction winch of claim 1, wherein: the central axis of the roller (511) is parallel to the central axis of the winding drum (3), and a groove (5111) for accommodating the peripheral wall of the cable (4) is concavely formed on the peripheral wall of the roller (511).

4. The automatic retraction winch of claim 2, wherein: slide bar (111) outer wall all is provided with fixed cover (1111), fixed cover (1111) fixed connection in draw inside main part (5), just fixed cover (1111) slide in slide bar (111) outer wall.

5. An automatic retraction winch according to claim 4, wherein: pressing member (52) include loose pulley (521), loose pulley (522) down, go up loose pulley (521) and loose pulley (522) down and overlap respectively and locate two fixed cover (1111) outer wall, the central axis of going up loose pulley (521) and loose pulley (522) down all is on a parallel with the central axis of gyro wheel (511), between loose pulley (521) and loose pulley (522) down is passed in noose (4), just noose (4) are located gyro wheel (511) and one of them between the loose pulley.

6. An automatic retraction winch according to claim 5, wherein: the two sides of the traction main body (5) are symmetrically provided with movable blocks (53), the movable blocks (53) are respectively provided with a first guide hole (531), a first guide post (5311) is arranged in the first guide hole (531), and the first guide post (5311) is fixedly connected to the traction main body (5); draw main part (5) both sides and all seted up guiding hole two (54), sliding connection is connected with guide post two (541) in guiding hole two (54), gyro wheel (511) rotate connect in guide post two (541), just guide post two (541) fixed connection in movable block (53).

7. An automatic retraction winch according to claim 6, wherein: the driving piece (512) comprises a shifting block (5121) and a gas spring (5122), the shifting block (5121) is hinged to the traction main body (5), an extrusion section (5123) is formed on the shifting block (5121), the extrusion section (5123) is used for abutting against the movable block (53) and applying downward pressure to the movable block (53), the gas spring (5122) is arranged between the traction main body (5) and the movable block (53), and the gas spring (5122) is used for applying upward elastic force to the movable block (53).

8. The automatic retraction winch of claim 2, wherein: the traction device is characterized in that reset springs (6) are arranged on two sides of the traction main body (5), the reset springs (6) are sleeved on the sliding rod (111), one ends of the reset springs (6) are tightly abutted to the support (11), and the other ends of the reset springs (6) are tightly abutted to the traction main body (5).

9. The automatic retraction winch of claim 2, wherein: the rope guide device is characterized in that a rope guide device (7) used for uniformly winding the rope (4) on the winding drum (3) is arranged on the mounting frame (1), the rope guide device (7) comprises a fixing plate (71) arranged on the mounting frame (1), a rope guide frame (72) hinged to the fixing plate (71), a rope guide rod (73) arranged on the rope guide frame (72) and used for supporting the rope (4), and a control cylinder (74) fixedly connected to the fixing plate (71), the rope guide rod (73) is rotatably connected to the rope guide frame (72), and the control cylinder (74) drives the rope guide rod (73) to be tightly attached to the rope (4) on the winding drum (3).

10. The automatic retraction winch of claim 1, wherein: the traction main body (5) is provided with at least two rotating rollers (55), and a limiting space (551) for the rope (4) to pass through is formed between the rotating rollers (55).