CN113800446A

CN113800446A - High-strength anti-breaking lifting equipment locking device convenient to limit

Info

Publication number: CN113800446A
Application number: CN202111169875.0A
Authority: CN
Inventors: 范林; 蔡卫东; 程圣; 杨本志; 王海峰; 陈为; 马飞
Original assignee: Haian Aoke Machinery Manufacturing Co ltd
Current assignee: Haian Aoke Machinery Manufacturing Co ltd
Priority date: 2021-10-08
Filing date: 2021-10-08
Publication date: 2021-12-17

Abstract

The invention relates to the technical field of lifting equipment, in particular to a high-strength anti-breakage lifting equipment locking device convenient to limit, which comprises a four-wheel drive operation conveying plate, wherein a cross rod is rotatably arranged at the top end of the four-wheel drive operation conveying plate, a telescopic cylinder is rotatably arranged at the top end of the four-wheel drive operation conveying plate, one side of the telescopic cylinder is rotatably connected with one side of the cross rod, a top plate is rotatably arranged at the top end of the cross rod, and one end of the cross rod is respectively and slidably arranged at the inner sides of the top plate and the four-wheel drive operation conveying plate. According to the invention, the self-locking mechanism is arranged, the auxiliary gear drives the centrifugal wheel in the centrifugal disc on one side to rapidly deviate and displace through the rotating rod, and the centrifugal wheel is clamped in the centrifugal disc through the engagement of one side of the centrifugal wheel and the inner clamping teeth, so that the rotation of the auxiliary gear on the same shaft is limited reversely, the auxiliary gear clamps the rack plate, the cross rod is limited, the top plate is prevented from rapidly descending, the safety of equipment is improved, and the damage of a bearing object is avoided.

Description

High-strength anti-breaking lifting equipment locking device convenient to limit

Technical Field

The invention relates to the technical field of lifting equipment, in particular to a high-strength anti-breaking locking device for the lifting equipment, which is convenient to limit.

Background

The lifting equipment is a multifunctional lifting mechanical equipment which can be divided into a fixed type, a movable type, a guide rail type, a crank arm type, a scissor fork type, a chain type, a loading and unloading platform and the like. The elevator is generally used in the fields of rescue, decoration and the like, and the lifting equipment frame is a lifting platform which can be adjusted up and down, and is mainly used for a mechanical working platform assembly and a lifting machine which can vertically convey people or objects. Also refers to equipment for vertical conveying in logistics systems such as factories and automatic warehouses, and various plane conveying equipment is often arranged on the lifting platform and is used as a connecting device for conveying lines with different heights.

For example, the fire engine with the publication number of CN105169600B and the liftable equipment frame has the technical proposal that: the locking device is arranged on the equipment frame body, the end part of the bolt of the locking device is matched with the bolt hole on the lower front connecting rod or the lower rear connecting rod when the equipment frame body is lifted to the highest position, and the locking device plays a role in locking the equipment frame body lifted to the highest position, and the invention has the beneficial effects that: it has the equipment frame and goes up and down conveniently, is convenient for take the equipment, takes the advantage that can also the fast recovery normal position after the equipment. Liftable equipment frame takes and resets fast for the equipment provides powerful assurance, and its overall structure is firm reliable can ensure safety, and liftable equipment frame design is novel, and the flexibility that goes up and down is strong, provides convenience for taking fast of liftoff higher article in the fire engine. It can be seen that the existing lifting apparatus frame has satisfied the basic use requirement of recovery of orthopedic patients, but the following problems still exist.

Many current lifting device mainly go up and down through electrified equipment such as cylinder, electric telescopic handle and motor, work as these equipment failures, lead to the roof to descend fast easily, take place danger easily, cause the bearing object to damage, consequently, need design a high strength that is convenient for spacing and prevent breaking lifting device locking device in order to solve above-mentioned problem.

Disclosure of Invention

The invention aims to provide a high-strength anti-breaking lifting equipment locking device convenient for limiting, and aims to solve the problems that many existing lifting equipment in the background art are lifted mainly through powered equipment such as a cylinder, an electric telescopic rod and a motor, when the equipment fails, a top plate is easy to rapidly descend, danger is easy to occur, and a load is damaged.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a lifting equipment locking device that breaks is prevented to high strength convenient to it is spacing, includes:

the four-wheel drive operation conveying plate comprises a four-wheel drive operation conveying plate, wherein a cross rod is rotatably mounted at the top end of the four-wheel drive operation conveying plate, a telescopic cylinder is rotatably mounted at the top end of the four-wheel drive operation conveying plate, one side of the telescopic cylinder is rotatably connected with one side of the cross rod, a top plate is rotatably mounted at the top end of the cross rod, one end of the cross rod is respectively slidably mounted at the inner sides of the top plate and the four-wheel drive operation conveying plate, a rectangular box is fixedly mounted at the top end of the top plate, an extension mechanism is fixedly mounted in the rectangular box, a lifting mechanism is fixedly mounted at the top end of the rectangular box, and a control box is fixedly mounted at the top end of the four-wheel drive operation conveying plate;

self-locking mechanism, including the rack board, the both sides on four-wheel drive operation transport plate top are all fixed mounting has the backup pad, two the top of backup pad is all fixed mounting has a set of cradling piece, two sets of the inside of cradling piece all rotates and installs the dwang, two the top of backup pad all fixed mounting has the centrifugal dish, and the inside of centrifugal dish passes the dwang, two the inside of dwang all fixed mounting has auxiliary gear, two the inside of centrifugal dish has all seted up interior latch, the outside block of dwang is installed and is equipped with centrifugal wheel, the both sides of roof all fixed mounting has the rack board, and auxiliary gear drives the centrifugal wheel of the inside centrifugal dish of one side through the dwang and takes place quick skew displacement, through one side and the meshing of interior latch of centrifugal wheel, makes centrifugal wheel block die in the inside of centrifugal dish to reverse restriction coaxial auxiliary gear rotates, the auxiliary gear clamps the rack plate, so that the cross rod is limited, the fast descending of the top plate is avoided, the safety of the equipment is improved, and the damage of a bearing object is avoided.

Preferably, the extension mechanism includes the slide rail, the spout has been seted up to the inside of rectangle case, the internal rotation of spout installs No. two threaded rods, No. two outside fixed mounting of threaded rod has No. two bevel gears and No. three bevel gears, No. two bevel gears and No. three bevel gear symmetric distribution are in the both sides of No. two threaded rods, No. one bevel gear is installed in No. two bevel gears's top meshing, No. one the threaded rod is installed in the top rotation of bevel gear, the screw thread piece is installed to all the screw threads in the both sides of No. two threaded rods, the bottom slidable mounting of screw thread piece is in the inside of spout, two the top of screw thread piece is all fixed mounting have the extension board for the extension board slides out the rectangle case, increases the extension area on rectangle case top, can place more article.

Preferably, two the top of extension board is all fixed mounting has the slipmat, the slipmat is the rubber material, and the slipmat increases and the object between the frictional property prevents the object landing.

Preferably, two the bottom of extension board is all fixed mounting have the supporting shoe, two the bottom of supporting shoe is all slidable mounting has the slide rail, and the supporting shoe slides in the inside of rectangular channel, and the supporting shoe can increase the support nature to the supporting shoe, prevents that the supporting shoe side atress is too much, increases the protection to the extension board.

Preferably, two rectangular channels have all been seted up to one side of slide rail, the bolt has been inserted to one side screw thread of supporting shoe, and the rotation bolt for the bolt is close to the rectangular channel, and the position of restriction supporting shoe prevents that the supporting shoe is unstable.

Preferably, the second threaded rod is provided with opposite threads on two sides of the shaft by taking the center as the center, and the threads of the second threaded rod are opposite, so that the threaded blocks can move in opposite directions.

Preferably, the lifting mechanism comprises a storage lifting barrel, a fixed plate is fixedly mounted at the top end of the rectangular box, the number of the fixed plates is two, two winding rollers are mounted on one sides, close to each other, of the fixed plates in a rotating mode, a motor is mounted on one side of each winding roller in a rotating mode, one side of the motor is fixedly connected with one side of the fixed plate, a pull rope is wound on the outer side of each winding roller, the storage lifting barrel is arranged in a clamping mode in one side of the pull rope in an extending mode, the pull rope is wound in a rotating mode through the winding rollers, the pull rope is upwards lifted, stored and lifted, articles can be conveniently transported to an upper end platform from a lower position, and the lifting mechanism is very practical and convenient for lifting of the articles in construction.

Preferably, the top of accomodating the lifting bucket is articulated installs the protective cover, accomodate one side of lifting bucket and protective cover all fixed mounting have a magnetic sheet, two the magnetic pole of magnetic sheet is opposite, with the protective cover card on accomodating the lifting bucket, the magnetic sheet adsorbs each other, prevents to accomodate that lifting bucket from promoting the process and taking place to rock and throw away article.

Compared with the prior art, the invention has the beneficial effects that:

1. through being provided with self-locking mechanism, the inside centrifugal wheel of centrifugal dish that auxiliary gear passes through the dwang and drives one side takes place quick skew displacement, and one side and the inside latch meshing through the centrifugal wheel for the centrifugal wheel card dies in the inside of centrifugal dish, thereby reverse restriction the coaxial auxiliary gear rotation of going up, auxiliary gear blocks the rack board, makes the crossbar by spacing, thereby has avoided the quick decline of roof, increases the security of equipment, has avoided the damage of carrier.

2. Through being provided with extension mechanism, a bevel gear takes place to rotate through rotatory No. two threaded rods that drive both sides, and No. two threaded rods drive the screw thread piece and rotate, and two screw thread pieces are to the slip of keeping away from the direction each other for the extension board slides out the rectangle case, increases the extension area on rectangle case top, can place more article, and the supporting shoe can increase the support nature to the supporting shoe, prevents that the supporting shoe side atress is too much, increases the protection to the extension board.

3. Through being provided with hoist mechanism for the rolling drum takes place to rotate, and the rotatory winding stay cord of rolling drum makes the stay cord upwards promote to accomodate and carry the stayguy, is convenient for transport article to the upper end platform from the low, promotes very practical convenient to article in the construction, with the protective cover card on accomodating and carry the stayguy, the magnetic sheet adsorbs each other, prevents to accomodate and carry the stayguy and promote the process and take place to rock and throw away article.

Drawings

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

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

FIG. 3 is a schematic cross-sectional view of the extension mechanism of the present invention;

FIG. 4 is a schematic top view of the gear and centrifugal plate of the present invention;

FIG. 5 is a schematic view of a centrifugal plate according to the present invention;

fig. 6 is a schematic front view of the lifting mechanism of the present invention.

In the figure: 110. four-wheel drive operation transport plate; 120. a cross bar; 130. a telescopic cylinder; 140. a control box; 150. a rectangular box; 160. a top plate; 200. a self-locking mechanism; 210. a rack plate; 211. an auxiliary gear; 212. a support rod; 213. a support plate; 214. a centrifugal pan; 215. rotating the rod; 216. an inner latch; 217. a centrifugal wheel; 300. an extension mechanism; 310. an extension plate; 311. a first threaded rod; 312. a first bevel gear; 313. a second threaded rod; 314. a second bevel gear; 315. a third bevel gear; 316. a chute; 317. a thread block; 318. a support block; 319. a rectangular groove; 320. a slide rail; 321. a bolt; 400. a lifting mechanism; 410. a pull-up barrel is accommodated; 411. pulling a rope; 412. a motor; 413. a winding roller; 414. a fixing plate; 415. a protective cover; 416. a magnetic sheet.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-6, an embodiment of the present invention is shown:

the utility model provides a lifting equipment locking device that breaks is prevented to high strength convenient to it is spacing, includes:

the four-wheel drive operation transport plate 110, the telescopic cylinder 130 and the motor 412 used in the present invention are all commercially available models, and the specific working principle thereof is well known in the art, and therefore, it will not be described herein, the output end of the control panel at one side of the four-wheel drive operation transport plate 110 is electrically connected to the input ends of the telescopic cylinder 130 and the motor 412 through wires, respectively, the cross bar 120 is rotatably installed at the top end of the four-wheel drive operation transport plate 110, the telescopic cylinder 130 is rotatably installed at the top end of the four-wheel drive operation transport plate 110, one side of the telescopic cylinder 130 is rotatably connected to one side of the cross bar 120, the top end of the cross bar 120 is rotatably installed with the top plate 160, one end of the cross bar 120 is slidably installed at the inner sides of the top plate 160 and the four-wheel drive operation transport plate 110, the top end of the top plate 160 is fixedly installed with the rectangular box 150, the extension mechanism 300 is fixedly installed inside the rectangular box 150, the top end of the rectangular box 150 is fixedly provided with a lifting mechanism 400, and the top end of the four-wheel drive operation transport plate 110 is fixedly provided with a control box 140;

the self-locking mechanism 200 comprises a rack plate 210, wherein two sides of the top end of the four-wheel drive operation conveying plate 110 are fixedly provided with supporting plates 213, the top ends of the two supporting plates 213 are fixedly provided with a group of support rods 212, the insides of the two groups of support rods 212 are rotatably provided with rotating rods 215, the top ends of the two supporting plates 213 are fixedly provided with centrifugal discs 214, the insides of the centrifugal discs 214 penetrate through the rotating rods 215, the insides of the two rotating rods 215 are fixedly provided with auxiliary gears 211, the insides of the two centrifugal discs 214 are respectively provided with inner clamping teeth 216, the outer sides of the rotating rods 215 are clamped and provided with centrifugal wheels 217, two sides of a top plate 160 are fixedly provided with the rack plate 210, a control box 140 starts a telescopic cylinder 130, a cross rod 120 moves up and down under the driving of the telescopic cylinder 130, when the telescopic cylinder 130 normally moves up and down, the descending speed of the telescopic cylinder 130 is slow, the self-locking mechanism 200 cannot be triggered, when the telescopic cylinder 130 fails, when the cross bar 120 descends rapidly, the rack plate 210 can drive the auxiliary gear 211 to rotate rapidly, the auxiliary gear 211 drives the centrifugal wheel 217 inside the centrifugal disc 214 on one side to generate rapid deviation displacement through the rotating rod 215, one side of the centrifugal wheel 217 is meshed with the inner clamping teeth 216, so that the centrifugal wheel 217 is clamped inside the centrifugal disc 214, the auxiliary gear 211 on the same shaft is limited to rotate reversely, the auxiliary gear 211 clamps the rack plate 210, the cross bar 120 is limited, the rapid descending of the top plate 160 is avoided, the safety of equipment is improved, and the damage of a bearing object is avoided.

Further, the extension mechanism 300 comprises a slide rail 320, a slide groove 316 is formed in the rectangular box 150, a second threaded rod 313 is rotatably installed in the slide groove 316, a second bevel gear 314 and a third bevel gear 315 are fixedly installed on the outer side of the second threaded rod 313, the second bevel gear 314 and the third bevel gear 315 are symmetrically distributed on two sides of the second threaded rod 313, a first bevel gear 312 is engaged with the top ends of the second bevel gear 314 and the third bevel gear 315, a first threaded rod 311 is rotatably installed on the top end of the first bevel gear 312, thread blocks 317 are threadedly installed on two sides of the second threaded rod 313, the bottom ends of the thread blocks 317 are slidably installed in the slide groove 316, extension plates 310 are fixedly installed on the top ends of the two thread blocks 317, a worker rotates the first bevel gear 312 by rotating the first threaded rod 311, the first bevel gear 312 rotates the second threaded rods 313 on two sides by rotating, the second threaded rod 313 drives the threaded blocks 317 to rotate, and the two threaded blocks 317 slide in the direction away from each other, so that the extension plate 310 slides out of the rectangular box 150, the extension area of the top end of the rectangular box 150 is increased, and more articles can be placed.

Further, the top ends of the two extending plates 310 are fixedly provided with non-slip mats, the non-slip mats are made of rubber, and the non-slip mats increase friction with an object to prevent the object from slipping off.

Furthermore, the bottom ends of the two extension plates 310 are both fixedly provided with supporting blocks 318, and the bottom ends of the two supporting blocks 318 are both slidably provided with sliding rails 320, so that the lateral surfaces of the supporting blocks 318 are prevented from being stressed too much, and the protection of the extension plates 310 is increased.

Further, rectangular channel 319 has all been seted up to one side of two slide rails 320, and one side screw thread of supporting shoe 318 has inserted bolt 321, prevents that supporting shoe 318 is unstable.

Furthermore, the second threaded rod 313 is provided with opposite threads on two sides of the center as an axis, so that the threaded blocks 317 can move in opposite directions.

Further, hoist mechanism 400 is including accomodating and carrying the pail 410, the top fixed mounting of rectangle case 150 has fixed plate 414, and the quantity of fixed plate 414 is two, two fixed plate 414 rotate one side that are close to each other and install winding drum 413, one side of winding drum 413 is rotated and is installed motor 412, one side of motor 412 and one side fixed connection of fixed plate 414, the outside winding of winding drum 413 has stay cord 411, one side extension block of stay cord 411 has accomodate and carries the pail 410, make stay cord 411 upwards promote to accomodate and carry the pail 410, be convenient for transport article from the low to the upper end platform, it is very practical convenient to promote article in the construction.

Furthermore, the top of accomodating the pail 410 is articulated to be installed protective cover 415, accomodates that one side of pail 410 and protective cover 415 is all fixed mounting has magnetic sheet 416, and the magnetic pole of two magnetic sheets 416 is opposite, prevents to accomodate that pail 410 promotes the process and takes place to rock and throw away article.

The working principle is as follows: when the device is used by a worker, firstly, the device is externally connected with a power supply, so as to provide electric support for the device, when the device is used, the control box 140 starts the telescopic cylinder 130, the cross rod 120 is driven by the telescopic cylinder 130 to move up and down, when the device normally moves up and down, the descending speed of the telescopic cylinder 130 is slow, the self-locking mechanism 200 cannot be triggered, when the telescopic cylinder 130 fails and the cross rod 120 descends rapidly, the rack plate 210 can drive the auxiliary gear 211 to rotate rapidly, the auxiliary gear 211 drives the centrifugal wheel 217 inside the centrifugal disc 214 on one side to generate rapid deviation displacement through the rotating rod 215, one side of the centrifugal wheel 217 is meshed with the inner clamping tooth 216, so that the centrifugal wheel 217 is clamped inside the centrifugal disc 214, the rotation of the auxiliary gear 211 on the same axis is limited reversely, the auxiliary gear 211 clamps the rack plate 210, and the cross rod 120 is limited, thereby avoiding rapid descent of the top plate 160.

The staff is through rotating threaded rod 311 No. one, make bevel gear 312 rotatory No. one, bevel gear 312 takes place rotatoryly through rotatory No. two threaded rods 313 that drive both sides, No. two threaded rods 313 drive screw block 317 and rotate, two screw block 317 are to the slip of the direction of keeping away from each other, make extension board 310 slide out rectangle case 150, increase the extension area on rectangle case 150 top, can place more article, supporting shoe 318 slides in the inside of rectangular channel 319, supporting shoe 318 can increase the support nature to supporting shoe 318, staff's swivel bolt 321, make bolt 321 be close to rectangular channel 319, the position of restriction supporting shoe 318.

The staff blocks protective cover 415 on accomodating and carry pull-up barrel 410, and magnetic sheet 416 adsorbs each other, and control box 140 starter motor 412 for take place to rotate winding drum 413, and winding drum 413 is rotatory to be twined stay cord 411, makes stay cord 411 upwards promote to accomodate and carry pull-up barrel 410, is convenient for transport article from the low to upper end platform.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims

1. The utility model provides a lifting equipment locking device that breaks is prevented to high strength convenient to it is spacing, its characterized in that includes:

the four-wheel drive operation conveying plate comprises a four-wheel drive operation conveying plate (110), wherein a cross rod (120) is rotatably installed at the top end of the four-wheel drive operation conveying plate (110), a telescopic cylinder (130) is rotatably installed at the top end of the four-wheel drive operation conveying plate (110), one side of the telescopic cylinder (130) is rotatably connected with one side of the cross rod (120), a top plate (160) is rotatably installed at the top end of the cross rod (120), one end of the cross rod (120) is respectively slidably installed at the inner sides of the top plate (160) and the four-wheel drive operation conveying plate (110), a rectangular box (150) is fixedly installed at the top end of the top plate (160), an extension mechanism (300) is fixedly installed inside the rectangular box (150), a lifting mechanism (400) is fixedly installed at the top end of the rectangular box (150), and a control box (140) is fixedly installed at the top end of the four-wheel drive operation conveying plate (110);

self-locking mechanism (200), including rack plate (210), the both sides on four-wheel drive operation transport plate (110) top are fixed mounting all has backup pad (213), two the top of backup pad (213) is fixed mounting all has a set of cradling piece (212), and is two the inside of cradling piece (212) is all rotated and is installed dwang (215), two the top of backup pad (213) is fixed mounting all has centrifugal disc (214), and the inside of centrifugal disc (214) passes dwang (215), two the inside of dwang (215) is fixed mounting all has auxiliary gear (211), two interior latch (216) have all been seted up to the inside of centrifugal disc (214), centrifugal wheel (217) are installed to the outside block of dwang (215), the both sides of roof (160) are fixed mounting all has rack plate (210).

2. The locking device of high-strength anti-break lifting equipment convenient for limiting as claimed in claim 1, wherein: the extension mechanism (300) comprises a slide rail (320), a slide groove (316) is arranged inside the rectangular box (150), a second threaded rod (313) is rotatably arranged in the sliding groove (316), a second bevel gear (314) and a third bevel gear (315) are fixedly arranged on the outer side of the second threaded rod (313), the second bevel gear (314) and the third bevel gear (315) are symmetrically distributed on two sides of the second threaded rod (313), the top ends of the second bevel gear (314) and the third bevel gear (315) are engaged with a first bevel gear (312), a first threaded rod (311) is rotatably arranged at the top end of the first bevel gear (312), both sides of the second threaded rod (313) are provided with threaded blocks (317) in a threaded manner, the bottom end of each threaded block (317) is slidably mounted in the corresponding sliding groove (316), and the top ends of the two threaded blocks (317) are fixedly provided with extension plates (310).

3. The locking device of high-strength anti-break lifting equipment convenient for limiting as claimed in claim 2, wherein: the top ends of the two extension plates (310) are fixedly provided with non-slip mats, and the non-slip mats are made of rubber materials.

4. The locking device of high-strength anti-break lifting equipment convenient for limiting as claimed in claim 2, wherein: the bottom ends of the two extension plates (310) are fixedly provided with supporting blocks (318), and the bottom ends of the two supporting blocks (318) are provided with sliding rails (320) in a sliding manner.

5. A high strength anti-break lifting device locking apparatus convenient to it is spacing of claim 4, characterized by: rectangular grooves (319) are formed in one sides of the two sliding rails (320), and bolts (321) are inserted into threads on one side of the supporting block (318).

6. The locking device of high-strength anti-break lifting equipment convenient for limiting as claimed in claim 2, wherein: the second threaded rod (313) takes the center as two sides of the shaft and is provided with opposite threads.

7. The locking device of high-strength anti-break lifting equipment convenient for limiting as claimed in claim 1, wherein: the lifting mechanism (400) comprises a containing lifting barrel (410), fixing plates (414) are fixedly mounted at the top end of the rectangular box (150), the number of the fixing plates (414) is two, a winding roller (413) is rotatably mounted on one side, close to each other, of the two fixing plates (414), a motor (412) is rotatably mounted on one side of the winding roller (413), one side of the motor (412) is fixedly connected with one side of the fixing plates (414), a pull rope (411) is wound on the outer side of the winding roller (413), and the containing lifting barrel (410) is clamped on one side of the pull rope (411) in an extending mode.

8. A high strength anti-break lifting device locking apparatus convenient to limit as claimed in claim 7, wherein: the top end of the storage lifting barrel (410) is hinged with a protective cover (415), magnetic sheets (416) are fixedly mounted on one sides of the storage lifting barrel (410) and the protective cover (415), and the magnetic poles of the two magnetic sheets (416) are opposite.