CN117361286A - Shear fork self-locking anti-drop limiting lifting appliance - Google Patents

Abstract

The utility model relates to a cut fork auto-lock anticreep spacing formula hoist, it includes the hoist body, including first hanging part and second hanging part, first hanging part with the second hanging part all includes hook clamping part, articulated portion and opening and shutting portion, first hanging part with the articulated portion of second hanging part articulates and forms and cuts fork structure, hook clamping part is used for stretching into the macropore of stove bottom and with the flange block of macropore bottom; the self-locking limiting assembly is arranged on the opening and closing part and comprises an active limiting piece arranged on the first hanging piece/the second hanging piece and a passive limiting piece arranged on the second hanging piece/the first hanging piece and used for being matched with the active limiting piece, and the connection state of the active limiting piece and the passive limiting piece is controlled to lock the relative positions of the first hanging piece and the second hanging piece. The single crystal furnace bottom hoisting operation safety protection device has the effects of guaranteeing single crystal furnace bottom hoisting operation safety and reducing potential safety hazards.

Description

Shear fork self-locking anti-drop limiting lifting appliance

Technical Field

The application relates to the field of lifting equipment, in particular to a shear fork self-locking anti-drop limiting lifting appliance.

Background

At present, when the bottom of a single crystal furnace is hoisted, two annular heads of a hoisting rope are usually utilized to enable the two annular heads to sink to the lower surfaces of large holes at two ends of the bottom of the furnace respectively, and then a steel rod penetrates through the space between the two annular heads, so that the steel rod transversely abuts against the lower surfaces of flanges of the two large holes of the bottom of the furnace. When in hoisting, an operator uses a lifting hook of the hoisting equipment to hang on the middle section of the hoisting rope to carry out hoisting operation. At this time, the stress points of the furnace bottom act on the two steel bars, but the axial direction of the steel bars is not limited, and if the steel bars are separated from the annular heads of the hoisting ropes, safety accidents are caused, and the hoisting operation process is not standardized.

Disclosure of Invention

In order to standardize operation, ensure single crystal furnace bottom hoist operation's safety, reduce the potential safety hazard, this application provides a shear fork auto-lock anticreep spacing formula hoist.

The application provides a shear fork auto-lock anticreep spacing formula hoist adopts following technical scheme:

a scissors self-locking anti-drop limit spreader, comprising:

the lifting appliance comprises a lifting appliance body, a lifting appliance body and a lifting appliance control device, wherein the lifting appliance body comprises a first lifting appliance and a second lifting appliance, the first lifting appliance and the second lifting appliance comprise a hooking clamping part, a hinge part and an opening and closing part, the hinge parts of the first lifting appliance and the second lifting appliance are hinged to form a scissor type structure, and the hooking clamping part is used for extending into a large hole of the bottom of a furnace and is clamped with a flange at the bottom of the large hole;

the self-locking limiting assembly is arranged at the opening and closing part and comprises an active limiting piece arranged on the first hanging piece/the second hanging piece and a passive limiting piece arranged on the second hanging piece/the first hanging piece and used for being matched with the active limiting piece, and the connection state of the active limiting piece and the passive limiting piece is controlled to lock the relative positions of the first hanging piece and the second hanging piece.

Through adopting above-mentioned technical scheme, before this application is through setting up the hoist body of cutting fork structure, hoist body is the lax state to with first hanging piece and second hanging piece stretch into the macropore of stove bottom, later control the open and shut portion that first hanging piece and second hung piece are close to each other and make the hoist body open, the angle of adjustment makes the hook clamping part of first hanging piece and second hanging piece all block with the flange of stove bottom macropore lower surface, guarantee with the connection stability of stove bottom; then maintaining the tensioning state of the lifting tool body, connecting the upper edge of the opening and closing part of the lifting tool body by using lifting equipment, and lifting the furnace bottom; due to the fact that the self-locking limiting assembly is arranged, after the hooking clamping portion and the flange are clamped, the active limiting piece and the passive limiting piece are connected, so that the angle between the first hanging piece and the second hanging piece is limited, the hooking clamping portion is always kept in a clamping state with the flange, safety and stability in hoisting are guaranteed, potential safety hazards are reduced, after hoisting is completed, connection between the active limiting piece and the passive limiting piece is released, and the hanger body is pulled out from a large hole.

Preferably, the active limiting piece is clamped or inserted with the passive limiting piece.

Through adopting above-mentioned technical scheme, be convenient for realize the connection of initiative locating part and passive locating part through block or grafting form, ensure the quick locking of hoist body angle of opening and shutting.

Preferably, the active limiting part is a limiting plate, the limiting plate is hinged to one side of the first hanging part/one side of the second hanging part and can rotate around a hinge point in a vertical plane, the passive limiting part is fixed on the second hanging part/the first hanging part and is on the same side as the active limiting part, and a limiting groove for the passive limiting part to be clamped in is formed in one side of the limiting plate.

Through adopting above-mentioned technical scheme, during the locking, around limiting plate and the articulated point rotation limiting plate of first hanging the piece/second for in the spacing groove of limiting plate is gone into to passive locating part card, in order to realize the block of initiative locating part and passive locating part, convenient connection.

Preferably, the active limiting part is fixedly/movably arranged at one side of the first hanging part/the second hanging part, an insertion hole for the passive limiting part to be inserted is formed in the second hanging part/the first hanging part, and a limiting hole for the passive limiting part to be inserted is formed in the active limiting part.

Through adopting above-mentioned technical scheme, when initiative locating part is fixed state, initiative locating part is the platy that extends to passive locating part direction, during the locking, inserts jack and spacing hole with passive locating part along the axis direction (the direction that hangs the piece with perpendicular to first hanging the piece/second hanging the piece), realizes the locking of hoist body angle that opens and shuts, and the installation is convenient.

Preferably, the limiting groove/limiting hole is formed in a plurality of positions along the length direction of the active limiting piece, and the position of the passive limiting piece clamped into the limiting groove/limiting hole controls the opening and closing angle of the first hanging piece and the second hanging piece.

Through adopting above-mentioned technical scheme, through adjusting the position that passive locating part card goes into (or inserts) spacing groove/spacing hole, can adjust the angle that opens and shuts of first piece and second piece that hangs, be convenient for find the hoist body with the best angle of bottom flange block, guarantee the safety and the stability of lifting by crane, reduce the probability of taking place the incident.

Preferably, the self-locking limiting assembly further comprises an anti-falling part for preventing the limiting plate from being separated from the passive limiting part, the anti-falling part is fixed on the limiting plate and located on one side of the notch of the limiting groove, the anti-falling part is used for guaranteeing that the notch of the limiting groove is opened before hoisting, and the notch of the limiting groove is blocked after the hooking clamping part is clamped with the flange at the bottom of the big hole.

Through adopting above-mentioned technical scheme, set up anticreep spare on the limiting plate, and set up the anticreep spare in one side of spacing groove notch, after limiting plate and passive limiting piece block, utilize the notch shutoff of anticreep spare with the spacing groove to the free rotation of restriction limiting plate avoids leading to limiting plate and passive limiting piece to break away from because of taking place to rock or unexpected circumstances such as collide with in the process of lifting by crane, guarantee the security of lifting by crane the in-process.

Preferably, the anti-falling piece comprises a sleeve fixed on one side of the limiting plate, an anti-falling long rod slidingly connected in the sleeve, and a control piece for controlling the extension or retraction of the anti-falling long rod.

Through adopting above-mentioned technical scheme, control piece pulling anticreep stock is in intraductal round trip sliding in order to control the top of anticreep stock and stretch out or retract intraductal, stretches out when the anticreep stock, then the notch shutoff of spacing groove, when the anticreep stock withdrawal, then opens the notch of spacing groove, be convenient for operation and control.

Preferably, the control member comprises a sleeve connected with the sleeve and a handle connected with the anti-falling long rod in the sleeve in a sliding manner, a deep groove is formed in the side wall of the sleeve along the axial direction of the sleeve, a shallow groove is formed in the bottom wall of the sleeve along the direction perpendicular to the axial direction of the sleeve, and the anti-falling long rod is retracted into the sleeve when the handle is clamped into the shallow groove.

Through adopting the technical scheme, the handle is vertically arranged with the anti-falling long rod, and can slide in the sleeve and rotate around the axis of the sleeve, when the handle is clamped in the shallow groove of the bottom wall of the sleeve, the anti-falling long rod is retracted in the sleeve, when the handle is rotated around the axis of the sleeve to enable the handle to fall out of the shallow groove and be clamped in the groove bottom of the deep groove, the top end of the anti-falling long rod is pushed out of the sleeve so as to seal the notch of the limiting groove; by arranging the shallow groove and the deep groove on the sleeve, the bottom of the deep groove is closer to the sleeve than the bottom of the shallow groove, the position where the handle is placed is controlled, the extension or retraction of the anti-drop long rod can be controlled, and the operation and control are convenient.

Preferably, the anti-falling part further comprises a pressure spring, one end of the anti-falling long rod, which is close to the sleeve, is annularly cut off along the direction perpendicular to the axis of the anti-falling long rod to form an avoidance groove, the pressure spring is sleeved outside the anti-falling long rod, and two ends of the pressure spring are respectively abutted to the groove wall of the avoidance groove and the top wall of the sleeve.

Through adopting above-mentioned technical scheme, set up the pressure spring, when the shallow slot is gone into to the handle card, anticreep stock withdrawal sleeve pipe is intraductal for the pressure spring compression, when needs are locked spacing stock, only need deviate from the shallow slot with the handle, and rotate the deep slot corresponding position with the handle, can drive the top of anticreep stock and stretch out under the restoring force effect of pressure spring, the handle card is gone into the deep slot and is butt at the tank bottom of deep slot.

Preferably, the hooking clamping part is in an outward L shape, the extension of the hooking clamping part extends upwards to form a supporting flanging, so that the hooking clamping parts and the connecting parts of the first hanging part and the second hanging part are combined to form a shape like a Chinese character 'ji', and the vertical section of the hooking clamping part extends to two sides to form abutting edges;

and a rubber pad is arranged at the position of the hook clamping part, which is abutted with the flange.

By adopting the technical scheme, the support flanging is arranged, so that the inner side edge of the flange at the bottom of the large hole can be clamped firmly, and the contact area with the outer side edge of the flange is increased by extending the two sides of the vertical section to form the abutting edge, so that the clamping part can be hooked firmly; the friction resistance between the hook clamping part and the flange is convenient to increase due to the arrangement of the rubber pad, and the probability of slipping in the lifting process is reduced.

In summary, the present application includes at least one of the following beneficial technical effects:

1. according to the lifting appliance, the opening and closing angle of the lifting appliance body can be adjusted by arranging the lifting appliance body with the scissor type structure, so that the hook clamping part can conveniently extend into the large hole in a loose state, the opening and closing angle is adjusted to enable the hook clamping part to be clamped and tensioned with the flange at the bottom of the large hole, the opening and closing angle of the lifting appliance body at the moment is locked through the self-locking limiting assembly, the hook clamping part and the flange are kept in a fastening and clamping state in the lifting process, the falling probability of the furnace bottom during lifting is reduced, the lifting safety is guaranteed, and the potential safety hazard is reduced;

2. by arranging a plurality of limiting grooves along the length direction of the limiting plate, the lifting appliance body can be conveniently locked at different opening and closing angles, and the opening and closing angles when the hook clamping part is fastened and matched with the flange can be conveniently found;

3. through the setting of anticreep spare, after limiting plate and passive locating part block, utilize the notch shutoff of anticreep spare with the spacing groove, avoid the limiting plate to rotate to lead to the breaking away from of limiting plate and passive locating part, guarantee the safety of lifting by crane in-process.

Drawings

Fig. 1 is a schematic view of the state of the present application during lifting.

Fig. 2 is a schematic view showing a state when the flange is engaged by the hooking and clamping portion.

Fig. 3 is a schematic view of the overall structure of the spreader of the present application.

Fig. 4 is a schematic partial cross-sectional view of a sleeve partially broken away to reveal the structure of the self-locking stop assembly.

Reference numerals illustrate: 01. a furnace bottom; 02. a large hole; 03. a flange; 1. a hanger body; 11. a first hanger; 12. a second hanger; 13. a hook clamping part; 131. supporting and flanging; 132. an abutting edge; 133. a rubber pad; 14. a hinge part; 15. an opening/closing section; 16. a pin shaft; 2. the self-locking limiting assembly; 21. an active limiting piece; 211. a limiting plate; 212. a limit groove; 22. a passive stop member; 23. plugging a screw; 24. an anti-falling member; 241. a sleeve; 242. an anti-drop long rod; 2421. an avoidance groove; 243. a control member; 2431. a sleeve; 2432. a handle; 2433. a deep groove; 2434. shallow grooves; 2435. a compression spring.

Detailed Description

The present application is described in further detail below in conjunction with figures 1-4.

Example 1

The embodiment of the application discloses a shear fork self-locking anti-drop limiting lifting appliance. Referring to fig. 1, 2 and 3, the scissor self-locking anti-drop limit type lifting appliance comprises a lifting appliance body 1 and a self-locking limit assembly 2 arranged on the lifting appliance body 1.

The lifting appliance body 1 comprises a first lifting element 11 and a second lifting element 12, wherein the first lifting element 11 and the second lifting element 12 respectively comprise a hook clamping part 13 which is used for extending into a large hole 02 of the furnace bottom 01 and is clamped with a flange 03 at the bottom of the large hole 02, a hinge part 14 which is used for being connected with each other, and an opening and closing part 15. The hinge parts 14 of the first and second crane parts 11, 12 are hinged by means of a pin 16, so that the spreader body 1 forms a scissor fork structure freely rotatable about the pin 16. In order to facilitate the hinging, the first hanger 11 and the second hanger 12 are both plate-shaped, and the hinge portion 14 forms a triangle with opposite sharp corners.

Before hoisting, the hook clamping part 13 of the hoist body 1 is kept in a loose state to extend into the large hole 02 of the furnace bottom 01, then the two opening and closing parts 15 of the first hoist part 11 and the second hoist part 12 are mutually close, and the opening and closing angle of the hoist body 1 is adjusted, so that the hook clamping part 13 is gradually opened, and the opening and closing angle of the hoist body 1 is continuously adjusted until the hook clamping part 13 is clamped with the flange 03 at the bottom of the large hole 02. The opening and closing angle of the lifting appliance body 1 at the moment is locked by using the self-locking limiting assembly 2.

Referring to fig. 3, the self-locking spacing assembly 2 includes an active spacing member 21 mounted on the opening and closing portion 15 of the first hanger 11/second hanger 12 and a passive spacing member 22 mounted on the opening and closing portion 15 of the second hanger 12/first hanger 11 for cooperation with the active spacing member 21. The locking of the relative positions of the first hanging piece 11 and the second hanging piece 12, namely the locking of the opening and closing angles of the hanger body 1, can be realized through the connection of the active limiting piece 21 and the passive limiting piece 22.

In order to facilitate the quick locking of the opening and closing angle, the connection mode of the active limiting piece 21 and the passive limiting piece 22 is a clamping or plugging mode or other modes which are convenient for quick connection. The present embodiment will be described by taking the example of the engagement connection between the active limiter 21 and the passive limiter 22.

Referring to fig. 3, at this time, the active limiting member 21 is a limiting plate 211, and the limiting plate 211 is hinged to one side of the first hanger 11/second hanger 12 by a stopper screw 23, and the limiting plate 211 can rotate in a vertical plane around the stopper screw 23. The second limiting member is fixed on the second hanger 12/the first hanger 11 and is located on the same side as the active limiting member 21. A limit groove 212 into which the passive limiting member 22 is engaged is formed in one side of the limit plate 211. Specifically, the passive limiting member 22 is a limiting pin fixed on the second hanging member 12/the first hanging member 11, and the limiting groove 212 is a U-shaped groove with a notch communicated with the outside and the notch faces the limiting pin. When the opening and closing angle of the lifting appliance body 1 is required to be locked, the limiting plate 211 is rotated around the stopper screw 23, so that the limiting pin is clamped into the limiting groove 212 of the limiting plate 211, and the clamping of the active limiting piece 21 and the passive limiting piece 22 is realized, so that the connection is convenient.

Referring to fig. 3, preferably, the limiting groove 212 may be formed in a plurality along the length direction of the active limiting member 21, and the opening and closing angles of the first hanging member 11 and the second hanging member 12 may be adjusted by adjusting the position of the passive limiting member 22 that is clamped (or inserted) into the limiting groove 212, so as to find the optimal angle of the hanger body 1 for clamping the bottom flange 03, ensure the safety and stability of the lifting, and reduce the probability of safety accidents.

In order to reduce the probability of the separation of the limiting plate 211 and the passive limiting piece 22 caused by shaking or accidental collision in the lifting process, the safety in the lifting process is ensured. The self-locking spacing assembly 2 further includes an anti-drop member 24 for preventing the spacing plate 211 from disengaging from the passive spacing member 22. The anti-falling member 24 is fixed on the limiting plate 211 and located at one side of the notch of the limiting groove 212. Before lifting, the notch of the limiting groove 212 is in an open state; after the hooking clamping part 13 is clamped with the flange 03 at the bottom of the large hole 02, the notch of the limiting groove 212 is blocked by the anti-falling piece 24 so as to limit the rotation of the limiting plate 211 and reduce the probability of the limiting plate 211 separating from the passive limiting piece 22.

Referring to fig. 3 and 4, in detail, the escape prevention member 24 includes a sleeve 241 fixed at one side of the limiting plate 211, an escape prevention long rod 242 slidably coupled in the sleeve 241, and a control member 243 controlling the escape prevention long rod 242 to be extended or retracted. When the top end of the control anti-drop long rod 242 extends out of the sleeve 241, the notch of the limit groove 212 is blocked; when the tip of the control anti-drop rod 242 is retracted into the sleeve 241, the notch of the limit groove 212 is opened. The anticreep piece 24 can be fixed in the one end that is close to stopper and beats screw 23 of limiting plate 211, also can set up in the one end of keeping away from stopper and beat screw 23, in order to be convenient for the operator to operate, this application is fixed anticreep piece 24 in the one end that stopper and beat screw 23 was kept away from to limiting plate 211, and the distal end of anticreep piece 24 is unsettled.

To facilitate defining the position of the anti-run bar 242 when extended or retracted, the control member 243 includes a sleeve 2431 coupled to the sleeve 241 and a handle 2432 slidably coupled within the sleeve 2431 and fixedly coupled to the anti-run bar 242. The handle 2432 is provided perpendicular to the anti-drop long rod 242, and the handle 2432 can slide in the axial direction of the sleeve 2431 and can rotate around the axial direction of the sleeve 2431. The side wall of the sleeve 2431 is provided with a deep groove 2433 with an extending direction parallel to the axis direction, and the bottom wall of the sleeve 2431 is provided with a shallow groove 2434 with an extending direction perpendicular to the axis direction. The bottom of the deep groove 2433 is closer to the anti-falling long rod 242 than the bottom of the shallow groove 2434, before hoisting, the handle 2432 is clamped into the shallow groove 2434, the top end of the anti-falling long rod 242 is retracted into the sleeve 241, and at the moment, the notch of the limiting groove 212 is opened, so that the clamping of the passive limiting piece 22 is not influenced. When the hook clamping portion 13 is engaged with the flange 03, the handle 2432 is pulled out of the shallow groove 2434, the handle 2432 is rotated to rotate the handle 2432 to the corresponding position of the deep groove 2433, and then the handle 2432 is pushed to the bottom of the deep groove 2433, so that the top end of the anti-drop long rod 242 can be driven to extend out to seal the notch of the limiting groove 212.

Referring to fig. 4, in order to prevent the handle 2432 from sliding along the axial direction of the deep groove 2433 under the external force, the anti-drop member 24 further includes a compression spring 2435. One end of the anti-drop long rod 242, which is close to the sleeve 2431, is annularly cut to a certain depth along the direction perpendicular to the axis of the anti-drop long rod to form an avoidance groove 2421, the compression spring 2435 is sleeved outside the part, and two ends of the compression spring 2435 are respectively abutted on the groove wall of the avoidance groove 2421 and the top wall of the sleeve 2431. When the handle 2432 is clamped into the shallow groove 2434, the anti-falling long rod 242 is retracted into the sleeve 241, so that the pressure spring 2435 is compressed, and when the opening and closing angle of the lifting appliance body 1 is required to be locked, the handle 2432 is driven to be clamped into the bottom of the deep groove 2433 under the action of the restoring force of the pressure spring 2435, so that the top end of the anti-falling long rod 242 extends out.

Referring to fig. 2 and 3, the hooking clamping portion 13 is L-shaped with an outward opening, and in order to ensure the fastening clamping of the hooking clamping portion 13 and the flange 03, the extension of the hooking clamping portion 13 is extended upward to form a support flange 131, so that the hooking clamping portion 13 and the connecting portion of the first hanger 11 and the second hanger 12 are combined to form a "table" shape. This arrangement facilitates the firm clamping of the inner side edges of the bottom flange 03 of the large hole 02. The vertical section of the hooking clamping part 13 extends to two sides to form the abutting edge 132, so that the contact area with the outer side edge of the flange 03 is increased, and the hooking clamping part 13 can be clamped stably.

Further, in order to reduce the possibility of slip occurring during lifting of the furnace bottom 01, a rubber pad 133 is fixed to the hooking and holding portion 13 at a position where it abuts against the flange 03.

The implementation principle of the shear fork self-locking anti-drop limiting lifting appliance is as follows: before hoisting, the active limiting piece 21 is not connected with the passive limiting piece 22, the opening and closing angle of the hanger body 1 can be freely adjusted, the hook clamping portion 13 of the hanger body 1 is in a loose state and stretches into the large hole 02 of the furnace bottom 01, after stretching into the large hole 02, the opening and closing portions 15 are controlled to be close to or far away from each other, and the opening and closing angle of the hanger body 1 is adjusted, so that the hook clamping portion 13 and the flange 03 are clamped. After the hook clamping parts 13 of the first hanging part 11 and the second hanging part 12 are clamped with the flange 03, an operator rotates the limiting plate 211 to clamp the passive limiting pin into the limiting groove 212, then the handle 2432 is pulled out of the shallow groove 2434, the handle 2432 is clamped into the bottom of the deep groove 2433 under the action of the restoring force of the pressure spring 2435, the top end of the anti-falling long rod 242 extends out to block the notch of the limiting groove 212, the rotation of the limiting plate 211 is limited, and the probability that the passive limiting part 22 is separated from the limiting plate 211 is reduced. After the lifting operation is completed, the handle 2432 is pulled back and snapped into the shallow slot 2434. The notch of the limit groove 212 is opened to disconnect the limit plate 211 from the passive limit piece 22 to pull out the spreader body 1 from the large hole 02.

Example 2

The embodiment of the present application differs from embodiment 1 only in that: the connection form of the active limiting member 21 and the passive limiting member 22 is different, and the active limiting member 21 and the passive limiting member 22 in the embodiment of the present application are connected in a plug-in form (not shown in the figure).

Specifically, the active limiting member 21 may be a plate fixedly or movably disposed on one side of the first hanger 11/the second hanger 12, and the distal end of the active limiting member 21 faces the direction of the second hanger 12/the first hanger 11. The passive stop 22 is a separate pin or spring pin arranged on the side of the second hanger 12/first hanger 11 facing away from the active stop 21. The second hanging piece 12/the first hanging piece 11 is provided with an inserting hole for inserting the passive limiting piece 22. The active limiting piece 21 is provided with a limiting hole for inserting the passive limiting piece 22. When in locking, the passive limiting piece 22 is inserted into the jack and the limiting hole along the axial direction of the jack (the direction perpendicular to the first hanging piece 11/the second hanging piece 12), so that the locking of the opening and closing angle of the hanger body 1 is realized, and the installation is convenient.

In order to reduce the probability of the passive limiting piece 22 falling out of the limiting hole, the top end of the passive limiting piece 22 is provided with external threads, and after the passive limiting piece 22 passes through the limiting hole, the top end of the passive limiting piece 22 is screwed with a nut, so that the nut and the active limiting piece 21 are tightly propped against each other.

The foregoing are all preferred embodiments of the present application, and are not intended to limit the scope of the present application in any way, therefore: all equivalent changes in structure, shape and principle of this application should be covered in the protection scope of this application.

Claims (10)

1. A shear fork auto-lock anticreep spacing formula hoist, its characterized in that: comprising the following steps:

the lifting appliance comprises a lifting appliance body (1), and comprises a first lifting appliance (11) and a second lifting appliance (12), wherein the first lifting appliance (11) and the second lifting appliance (12) comprise a hook clamping part (13), a hinge part (14) and an opening and closing part (15), the hinge part (14) of the first lifting appliance (11) and the second lifting appliance (12) are hinged to form a scissor type structure, and the hook clamping part (13) is used for extending into a large hole (02) of a furnace bottom (01) and is clamped with a flange (03) at the bottom of the large hole (02);

the self-locking limiting assembly (2) is arranged on the opening and closing part (15) and comprises an active limiting piece (21) arranged on the first hanging piece (11)/the second hanging piece (12) and a passive limiting piece (22) arranged on the second hanging piece (12)/the first hanging piece (11) and used for being matched with the active limiting piece (21), and the connection state of the active limiting piece (21) and the passive limiting piece (22) is controlled to lock the relative positions of the first hanging piece (11) and the second hanging piece (12).

2. The scissors self-locking anti-drop limit type lifting appliance according to claim 1, wherein: the active limiting piece (21) is clamped or inserted with the passive limiting piece (22).

3. The scissors self-locking anti-drop limit type lifting appliance according to claim 2, wherein: the active limiting piece (21) is a limiting plate (211), the limiting plate (211) is hinged to one side of the first hanging piece (11)/the second hanging piece (12) and can rotate around a hinge point in a vertical plane, the passive limiting piece (22) is fixed on the second hanging piece (12)/the first hanging piece (11) and is on the same side as the active limiting piece (21), and a limiting groove (212) for the passive limiting piece (22) to clamp in is formed in one side of the limiting plate (211).

4. The scissors self-locking anti-drop limit type lifting appliance according to claim 2, wherein: the active limiting piece (21) is fixedly/movably arranged on one side of the first hanging piece (11)/the second hanging piece (12), an inserting hole for inserting the passive limiting piece (22) is formed in the second hanging piece (12)/the first hanging piece (11), and a limiting hole for inserting the passive limiting piece (22) is formed in the active limiting piece (21).

5. The scissors self-locking anti-drop limit sling according to any one of claims 3 and 4, wherein: the limiting grooves (212)/limiting holes are formed in a plurality of positions along the length direction of the active limiting piece (21), and the positions of the passive limiting pieces (22) clamped into the limiting grooves (212) control the opening and closing angles of the first hanging pieces (11) and the second hanging pieces (12).

6. The scissors self-locking anti-drop limit sling according to claim 3, wherein: the self-locking limiting assembly (2) further comprises an anti-falling part (24) used for preventing the limiting plate (211) from being separated from the passive limiting part (22), the anti-falling part (24) is fixed on the limiting plate (211) and located on one side of a notch of the limiting groove (212), the anti-falling part (24) is used for guaranteeing before lifting, the notch of the limiting groove (212) is opened, and the notch of the limiting groove (212) is blocked after the hooking clamping part (13) is clamped with a flange (03) at the bottom of the large hole (02).

7. The scissors self-locking anti-drop limit sling according to claim 6, wherein: the anti-falling piece (24) comprises a sleeve (241) fixed on one side of the limiting plate (211), an anti-falling long rod (242) which is connected in the sleeve (241) in a sliding mode, and a control piece (243) for controlling the anti-falling long rod (242) to extend or retract.

8. The scissors self-locking anti-drop limit sling according to claim 7, wherein: the control member (243) comprises a sleeve (2431) connected with the sleeve (241) and a handle (2432) connected with the anti-drop long rod (242) in the sleeve (2431) in a sliding manner, a deep groove (2433) is formed in the side wall of the sleeve (2431) along the axial direction of the sleeve (2431), a shallow groove (2434) is formed in the bottom wall of the sleeve (2431) along the direction perpendicular to the axial direction of the sleeve (2431), and the handle (2432) is clamped into the shallow groove (2434) when the anti-drop long rod (242) is retracted into the sleeve (241).

9. The scissors self-locking anti-drop limit sling according to claim 8, wherein: the anti-drop piece (24) further comprises a pressure spring (2435), one end of the anti-drop long rod (242) close to the sleeve (2431) is annularly cut off along the direction perpendicular to the axis of the sleeve to form an avoidance groove (2421), the pressure spring (2435) is sleeved outside the anti-drop long rod (242), and two ends of the pressure spring (2435) are respectively abutted to the groove wall of the avoidance groove (2421) and the top wall of the sleeve (2431).

10. The scissors self-locking anti-drop limit type lifting appliance according to claim 1, wherein: the hooking clamping part (13) is in an L shape with an outward opening, a supporting flanging (131) is formed by extending the extension of the hooking clamping part (13) upwards, so that the hooking clamping parts (13) of the first hanging piece (11) and the second hanging piece (12) are combined with the connecting part to form a shape like a Chinese character 'ji', and the vertical section of the hooking clamping part (13) extends to two sides to form a butting edge (132);

a rubber pad (133) is arranged at the position of the hooking clamping part (13) which is abutted against the flange (03).