CN219646807U

CN219646807U - Portable waterproof coating filter-pressing equipment

Info

Publication number: CN219646807U
Application number: CN202321287546.0U
Authority: CN
Inventors: 廖庆灯; 李娟�
Original assignee: Zhejiang Wofu Building Materials Technology Co ltd
Current assignee: Zhejiang Wofu Building Materials Technology Co ltd
Priority date: 2023-05-25
Filing date: 2023-05-25
Publication date: 2023-09-08
Anticipated expiration: 2033-05-25

Abstract

The utility model belongs to the technical field of waterproof paint production, and particularly relates to a convenient waterproof paint filter pressing device, which comprises: the device comprises a waterproof coating filter pressing box, a filter plate, an extrusion plate and a lifting device; the filter top lateral cycle removes and is provided with the loose mechanism in filter top, the inside upside lateral shifting of waterproof coating filter-pressing case is provided with a set of stripper plate bottom clearance mechanism, stripper plate bottom clearance mechanism groove has been seted up on the waterproof coating filter-pressing case inner wall that stripper plate bottom clearance mechanism both sides correspond, the loose mechanism groove in filter top has been seted up on the waterproof coating filter-pressing case inner wall that filter top loose mechanism both sides correspond, stripper plate bottom clearance mechanism one end is connected with the clearance mechanism power pack of setting in waterproof coating filter-pressing case inner wall, loose mechanism power pack in waterproof coating filter-pressing case inner wall is set up in loose mechanism one end in filter top is connected with, this equipment automation operation moves, the periodic control clearance, it is abundant to filter, fast, and high efficiency.

Description

Portable waterproof coating filter-pressing equipment

Technical Field

The utility model belongs to the technical field of waterproof coating production, and particularly relates to a convenient waterproof coating filter pressing device.

Background

The waterproof coating is prepared by mixing a base material with other additives, and the waterproof film formed by curing the waterproof coating has certain extensibility, elastoplasticity, crack resistance, impermeability and weather resistance, can play roles in waterproof, impermeable and protective, and needs to filter-press materials in the production process, so that impurities in the materials are filtered, and the production quality is improved.

The prior patent application number is: 2021105037869 the utility model discloses a convenient waterproof coating filter-pressing equipment, including waterproof coating filter-pressing equipment base station, the top of waterproof coating filter-pressing equipment base station is provided with waterproof coating filter-pressing equipment frame, the one end fixedly connected with controlling means of waterproof coating filter-pressing equipment frame, the inboard of waterproof coating filter-pressing equipment frame is fixedly installed hydraulic means, through supplementary push pedal and spacing pressurization board cooperation, drive cambered surface clamp plate and convex piece and extrude the coating, cooperate hydrophobicity and elasticity platform and the resilience of expansion bag of convex piece, make the filter effect of equipment more high-efficient, the impurity of avoiding most equipment to adopt the mode of direct screening and get the clear away of unnecessary moisture, owing to filter-pressing means, its meaning is to carry out the extrusion when filtering waterproof coating increases the efficiency of filtration, but during operation of above-mentioned equipment, owing to dead center in the waterproof coating production and other additives itself have certain viscosity, filter-pressing equipment is when carrying out the filter-pressing to it, to the pressure structure of exerting pressure and the filter screen structure of filtering, its surface all very easily bonds some raw materials of coating, and be difficult to with the clearance, the filter-pressing effect of continuous waterproof coating can be difficult to take place, the filter-pressing effect is not fully or filtration raw materials that the filter-pressing is not influenced by the realization of continuous filtration;

therefore, in view of the above-mentioned problems, the present utility model proposes a new and convenient waterproof paint filter pressing apparatus.

Disclosure of Invention

The embodiment of the utility model aims to provide convenient waterproof coating filter pressing equipment, and aims to solve the problems.

The utility model is realized by the following steps of: the device comprises a waterproof coating filter pressing box, a filter plate, an extrusion plate and a lifting device; the filter is installed in waterproof coating filter-pressing case inside one side for to the waterproof coating raw materials that inputs into it filters, filter plate over the elevating system is provided with the stripper plate, the stripper plate top is connected with elevating gear, start elevating gear control stripper plate and move towards the filter direction promptly, the waterproof coating raw materials of filtering on the opposition filter board extrudes, then cooperate with the filter to realize the operation to waterproof coating filter-pressing, filter top horizontal circulation movement is provided with filter top loose mechanism, filter top loose mechanism is used for carrying out the loosening and stirring to the waterproof coating raw materials that is in the filter-pressing on the filter, reduce the probability of waterproof coating raw materials adhesion at the filter top when increasing waterproof coating raw materials fluffy form, thereby improve filter to waterproof coating raw materials filtration's sufficiency, be located waterproof coating filter-pressing case inside upside lateral movement and be provided with a set of stripper plate bottom clearance mechanism, when elevating gear control stripper plate moves to stripper plate bottom clearance mechanism upside, stripper plate bottom lateral movement is followed the stripper plate bottom contact, then, under the action of gravity, the waterproof coating raw materials of scraping falls on the filter plate, and keep the filter bottom of the waterproof coating raw materials of being in the filter-pressing on the filter plate to be convenient for carrying out the filter-pressing mechanism and setting up the filter-pressing mechanism on the filter plate bottom the filter-pressing case, the filter plate is had corresponding to the filter-pressing mechanism of the filter-pressing mechanism is cleared up on the filter plate bottom the filter-pressing case bottom, the filter plate bottom clearance mechanism is had, the filter-pressing mechanism is had corresponding to the filter-pressing mechanism is had been had to the filter-pressing mechanism on the filter plate bottom on the bottom side of the bottom side, the loose mechanism inslot portion in filter top is used for depositing the loose mechanism in filter top, the setting in the loose mechanism groove in stripper bottom clearance mechanism groove in filter top, the loose mechanism in filter top groove in setting up mainly used prevents the smooth lift of stripper bottom clearance mechanism, the loose mechanism in extension influence stripper top in filter top, stripper bottom clearance mechanism one end is connected with the clearance mechanism power pack of setting in waterproof coating filter-pressing case inner wall, loose mechanism power pack in filter top is connected with the loose mechanism power pack of setting in waterproof coating filter-pressing case inner wall, clearance mechanism power pack and loose mechanism power pack drive respectively the stripper bottom clearance mechanism that corresponds, the loose mechanism lateral cycle of filter top removes, carry out corresponding clearance and loose to stripper bottom and filter top, realize the function of automated control operation.

According to the portable waterproof coating filter pressing equipment provided by the utility model, the upper side of the filter plate and the bottom of the extrusion plate are respectively provided with the extrusion plate bottom cleaning mechanism and the filter plate top loosening mechanism which are circularly and transversely moved, the bottom of the extrusion plate is regularly cleaned, the waterproof coating raw materials at the top of the filter plate are stirred and loosened, the sufficiency of filtering the waterproof coating raw materials and the accuracy of extrusion of the waterproof coating raw materials by falling of the extrusion plate are maintained, so that the automatic and efficient operation function of the device is increased, and meanwhile, the automatic operation is realized, and the convenience of use is increased.

Drawings

Fig. 1 is a schematic diagram of a partial front view internal structure of a portable waterproof coating filter pressing device.

Fig. 2 is a schematic view of a local connection structure of a filter plate and a waterproof coating filter-pressing box in the portable waterproof coating filter-pressing device.

Fig. 3 is a schematic view of a local connection structure of the extrusion plate and the waterproof coating filter-pressing box in the portable waterproof coating filter-pressing device.

Fig. 4 is a schematic structural view of a top loosening mechanism of a filter plate in the portable waterproof coating filter pressing equipment.

Fig. 5 is a schematic structural view of a mechanism for cleaning the bottom of an extrusion plate in a portable waterproof coating filter pressing device;

FIG. 6 is an enlarged schematic view of structure A in FIG. 4;

in the accompanying drawings: the waterproof coating filter pressing box 10, a filter plate 11, a squeeze plate 12, a lifting device 13, a squeeze plate bottom cleaning mechanism groove 14, a filter plate top loosening mechanism groove 15, a squeeze plate bottom cleaning mechanism 16, a filter plate top loosening mechanism 17, a scraping plate 18, a clamping pin 19, a clamping hole 20, a loosening rod 21, a connecting rod 22, a first spring 23, a first lead screw 24, a first nut 25, a first servo motor 26, a second lead screw 27, a second nut 28, a second servo motor 29, a roller 30, a wavy track 31, a buffer rod 32, a buffer cavity 33 and a second spring 34.

Detailed Description

The present utility model will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present utility model more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

Specific implementations of the utility model are described in detail below in connection with specific embodiments.

As shown in fig. 1, the structure diagram of the portable waterproof coating filter pressing device provided by the embodiment of the utility model includes: a waterproof coating filter pressing box 10, a filter plate 11, an extrusion plate 12 and a lifting device 13; the filter plate 11 is arranged at one side of the inside of the waterproof coating filter pressing box 10 and is used for filtering waterproof coating raw materials input into the filter pressing box, the extruding plate 12 is arranged in a lifting manner right above the filter plate 11, the top of the extruding plate 12 is connected with the lifting device 13, namely, the lifting device 13 is started to control the extruding plate 12 to move towards the direction of the filter plate 11, the waterproof coating raw materials filtered on the filter plate 11 are extruded and then matched with the filter plate 11 to realize the operation of filtering the waterproof coating, the top of the filter plate 11 is horizontally and circularly moved and is provided with the loosening mechanism 17 at the top of the filter plate, the loosening mechanism 17 at the top of the filter plate is used for loosening and stirring the waterproof coating raw materials which are in filter pressing on the filter plate 11, the probability that the waterproof coating raw materials are adhered at the top of the filter plate 11 is reduced while the loosening shape of the waterproof coating raw materials is increased, and the filtering sufficiency of the waterproof coating raw materials of the filter plate 11 is improved, a group of extrusion plate bottom cleaning mechanisms 16 are arranged on the upper side of the inside of the waterproof coating filter pressing box 10 in a transverse moving manner, when the lifting device 13 controls the extrusion plate 12 to move to the upper side of the extrusion plate bottom cleaning mechanisms 16, the extrusion plate bottom cleaning mechanisms 16 transversely move along the bottom of the extrusion plate 12 in a contact manner, the waterproof coating raw materials adhered to the bottom of the extrusion plate 12 are scraped, then the scraped waterproof coating raw materials fall on the filter plate 11 under the action of gravity, the bottom of the extrusion plate 12 is kept clean, the waterproof coating raw materials on the filter plate 11 are conveniently and fully extruded again, extrusion plate bottom cleaning mechanism grooves 14 are formed on the inner walls of the waterproof coating filter pressing box 10 corresponding to the two sides of the extrusion plate bottom cleaning mechanisms 16, the extrusion plate bottom cleaning mechanism grooves 14 are used for storing the extrusion plate bottom cleaning mechanisms 16, the inner wall of the waterproof coating filter pressing case 10 corresponding to the two sides of the filter top loose mechanism 17 is provided with a filter top loose mechanism groove 15, the inside of the filter top loose mechanism groove 15 is used for storing the filter top loose mechanism 17, the setting of the filter top loose mechanism groove 15 is mainly used for preventing the smooth lifting of the extrusion plate 12 due to the extension of the extrusion plate bottom cleaning mechanism 16 and the filter top loose mechanism 17, one end of the extrusion plate bottom cleaning mechanism 16 is connected with a cleaning mechanism power assembly arranged in the inner wall of the waterproof coating filter pressing case 10, one end of the filter top loose mechanism 17 is connected with a loose mechanism power assembly arranged in the inner wall of the waterproof coating filter pressing case 10, the cleaning mechanism power assembly and the loose mechanism power assembly respectively drive the corresponding extrusion plate bottom cleaning mechanism 16 and the filter top loose mechanism 17 to transversely circulate, and correspondingly clean and loose the bottom of the extrusion plate 12 and the top of the filter 11, and the function of automatic control operation is realized.

In the embodiment of the present utility model, the lifting device 13 may be configured as a hydraulic cylinder-hydraulic rod, a lifting motor or an electric telescopic rod, and the specific selection is determined according to practical situations, which will not be described herein, and the problems of outputting and cleaning the waterproof coating filtered by the filter plate 11 and the impurities remained on the filter plate 11, which are filtered, all belong to the prior art, and will not be described in detail in the present technical scheme;

the extrusion plate 12 is made of metal material, and has good corrosion resistance while keeping a large weight; the area of the extrusion plate 12 is the same as that of the filter plate 11, when the extrusion plate 12 moves towards the filter plate 11, the waterproof coating raw material on the upper side of the extrusion plate can be fully extruded and filtered, and the height set by the extrusion plate bottom cleaning mechanism groove 14 is the same as the highest height of the extrusion plate 12 controlled by the lifting device 13, so that the extrusion plate bottom cleaning mechanism 16 is accurately controlled to move from the extrusion plate bottom cleaning mechanism groove 14, and then the bottom of the extrusion plate 12 is scraped and cleaned.

In one example of the present utility model, referring to fig. 5, the bottom cleaning mechanism 16 for squeeze plate includes a base for scraping plate having the same length as the width of squeeze plate 12, the top of the base for scraping plate is detachably provided with a scraping plate 18, the vertical section of the scraping plate 18 is configured as a right triangle structure, when the squeeze plate 12 moves to the highest position, the scraping plate 18 is moved to the outside of the bottom cleaning mechanism groove 14 for squeeze plate, at this time, the top of the scraping plate 18 contacts with the bottom of squeeze plate 12, and then the scraping plate 18 is controlled to scrape the raw material adhered to the bottom of squeeze plate 12 in a horizontal circulation movement manner under the driving of the power component of the cleaning mechanism;

specifically, the top of the scraping plate base is provided with a plurality of clamping holes 20 at equal intervals along the length direction of the scraping plate base, the bottom of the scraping plate 18 is fixedly provided with clamping pins 19 corresponding to the positions of the clamping holes 20, and the clamping pins 19 are clamped in the clamping holes 20, so that the scraping plate 18 and the scraping plate base are detachably mounted;

referring to fig. 3, the power assembly of the cleaning mechanism includes a first nut 25 installed on one side of the base of the scraping plate, the first nut 25 is disposed in the inner wall of the filter pressing case 10 of the waterproof coating, the middle thread of the first nut 25 is connected with a first screw 24 horizontally and rotatably disposed in the wall of the filter pressing case 10 of the waterproof coating, one end of the first screw 24 is rotatably connected in the filter pressing case 10 of the waterproof coating through a bearing, the other end is connected with a first servo motor 26, the wall of the filter pressing case 10 of the waterproof coating corresponding to the first screw 24 is provided with a slide way, a phase guiding device for limiting rotation of the first nut 25 is disposed on the first nut 25, that is, the first servo motor 26 is started to drive the first screw 24 to rotate, then the first nut 25 is synchronously controlled to move along the first screw 24 horizontally and circularly, then the scraping plate 18 on the base of the scraping plate is driven to scrape the bottom of the extruding plate 12, one end of the base of the scraping plate, which is far from the first nut 25 is connected with a slide way, and the wall of the filter pressing case 10 of the corresponding waterproof coating is provided with a slide way, that slides in the slide way, and the base of the sliding bar is kept to move horizontally and stably under the driving of the first nut 25.

Referring to fig. 4, the loosening mechanism 17 at the top of the filter plate comprises a loosening plate with the same length as the width of the filter plate 11, a plurality of loosening rods 21 are elastically arranged at equal intervals along the length direction of one side of the loosening plate facing the filter plate 11, the bottom ends of the loosening rods 21 are in non-contact connection with the top of the filter plate 11, the distance between the loosening rods is smaller than 1 cm, the loosening rods 21 are driven to transversely move along the filter plate 11 under the action of a power component of the loosening mechanism, the waterproof coating raw materials on the loosening rods are continuously stirred and loosened, the filtering speed and the filtering quality of the loosening rods are increased, the loosening rods 21 are elastically connected with the loosening plate, and when the transverse movement encounters an object impurity with certain excessive hardness, the loosening rods 21 and the loosening plate are longitudinally buffered with certain capacity, so that the damage degree to the loosening rods 21 and the loosening plate is reduced;

specifically, the bottom end of the loosening rod 21 is of an arc structure, resistance applied during transverse movement is reduced, the top end of the loosening rod 21 is connected with a connecting rod 22 arranged in the loosening plate, a telescopic cavity is formed in the loosening plate corresponding to the connecting rod 22, the top end of the connecting rod 22 is connected with a first spring 23 arranged in the telescopic cavity, namely, the elastic effect of the first spring 23 is utilized to provide a longitudinal buffering function for the loosening rod 21;

referring to fig. 2, the power assembly of the loosening mechanism comprises an elastic connecting piece arranged at one side of a conveying plate, the end part of the elastic connecting piece is connected with a second nut 28, the middle part of the second nut 28 is transversely connected with a second screw 27 arranged in the inner wall of the waterproof paint filter-pressing box 10 in a threaded manner, one end of the second screw 27 is connected with a second servo motor 29, the other end of the second screw is rotatably connected in the wall of the waterproof paint filter-pressing box 10 through a bearing, a phase guiding device for limiting the rotation of the second screw 28 is arranged on the second nut 28, a roller 30 is arranged at the other side of the loosening plate, a wavy track 31 is arranged on the wall of the waterproof paint filter-pressing box 10 corresponding to the roller 30, the roller 30 rolls along the wavy track 31, namely, the second servo motor 29 is started to drive the second screw 27 to rotate, then the second nut 28 is controlled to circularly reciprocate along the second screw 27, thereby driving the loosening plate to transversely move along the top of the filter plate 11, and under the action of the elastic connecting piece, the roller 30 transversely moves synchronously along the wavy track 31, keeps the loosening rod 21 and circularly oscillates along the length direction of the loosening plate, thereby bidirectionally stirring and loosening waterproof paint on the filter plate 11;

specifically, referring to fig. 6, the elastic connection piece includes a buffer rod 32 connected to one side of the second nut 28, one end of the buffer rod 32 facing the loosening plate is elastically connected with a second spring 34, an end of the second spring 34 is connected to the loosening plate, a buffer cavity 33 is installed on the loosening plate located outside the second spring 34, the second spring 34 is disposed in the buffer cavity 33, the buffer cavity 33 is used for limiting the left-right swing of the second spring 34, that is, by using the connection between the buffer rod 32 and the second spring 34, the retaining roller 30 and the wavy track 31 can synchronously move under the operation of the second nut 28, when the second spring 34 is in a free state, the control roller 30 contacts with a recess of the wavy track 31, thereby when the retaining roller 30 moves to a protrusion on the wavy track 31, the second spring 34 is in a compressed state, and thus the loosening plate is controlled to perform cyclic swing by a certain distance.

In the above embodiment of the utility model, the convenient waterproof paint filter pressing device is provided, when in use, the waterproof paint to be filter-pressed is placed in the waterproof paint filter pressing box 10, then falls onto the filter plate 11 under the gravity, the waterproof paint is automatically filtered by the filter plate 11, in the filtering process, the bottom cleaning mechanism 16 of the extrusion plate and the loosening mechanism 17 at the top of the filter plate are all positioned in the corresponding groove 14 of the bottom cleaning mechanism of the extrusion plate, at this time, the lifting device 13 is started to drive the extrusion plate 12 to fall down, the waterproof paint raw material on the filter plate 11 is extruded, the filter plate 11 is matched for filter pressing operation, after each specified filter pressing time, the lifting device 13 controls the extrusion plate 12 to move back to the highest position, at this time, the first servo motor 26 and the second servo motor 29 are started at the same time, the bottom cleaning mechanism 16 of the extrusion plate and the loosening mechanism 17 at the top of the filter plate are driven to respectively reciprocate along the bottom of the extrusion plate 12 and the top of the filter plate 11, the bottom cleaning mechanism 16 of the extrusion plate is controlled to scrape the bottom of the extrusion plate 12 when the extrusion plate is moved, the loosening mechanism 17 at the top of the filter plate is driven to clean the bottom of the extrusion plate 12, the loosening mechanism 21 is driven to move around when the loosening mechanism 17 at the filter plate moves, the waterproof paint raw material on the filter plate 11 is driven to move back and the waterproof paint raw material on the filter plate 11 to the bottom and the filter material is fully filtered by the stirring mechanism of the filter plate and the bottom and the water-proof paint is repeatedly cleaned by the lifting device at the bottom speed of the bottom 16.

The foregoing description of the preferred embodiments of the utility model is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the utility model.

Claims

1. Portable waterproof coating filter-pressing equipment, its characterized in that, portable waterproof coating filter-pressing equipment includes: a waterproof coating filter pressing box (10), a filter plate (11), an extrusion plate (12) and a lifting device (13); the filter (11) is installed in inside one side of waterproof coating filter-pressing case (10), over-and-under type is provided with stripper plate (12) directly over filter (11), and stripper plate (12) top is connected with elevating gear (13), the lateral cycling in filter (11) top is provided with filter top loose mechanism (17), is located inside upside lateral shifting of waterproof coating filter-pressing case (10) and is provided with a set of stripper plate bottom clearance mechanism (16), has seted up stripper plate bottom clearance mechanism groove (14) on waterproof coating filter-pressing case (10) inner wall that is located stripper plate bottom clearance mechanism (16) both sides correspondence, has seted up filter top loose mechanism groove (15) on waterproof coating filter-pressing case (10) inner wall that filter top loose mechanism (17) both sides correspond, stripper plate bottom clearance mechanism (16) one end is connected with the loose mechanism power pack of setting in waterproof coating filter-pressing case (10) inner wall, and loose mechanism power pack in filter top loose mechanism (17) one end is connected with the setting in waterproof coating filter-pressing case (10) inner wall.

2. The portable waterproof coating filter pressing equipment according to claim 1, wherein the area of the extrusion plate (12) is the same as that of the filter plate (11), and the height of the extrusion plate bottom cleaning mechanism groove (14) is the same as that of the lifting device (13) for controlling the extrusion plate (12) to be lifted to the highest height.

3. The portable waterproof coating filter pressing device according to claim 2, wherein the squeezing plate bottom cleaning mechanism (16) comprises a scraping plate base with the same length as the squeezing plate (12) in width, the scraping plate (18) is detachably mounted on the top of the scraping plate base, and the vertical section of the scraping plate (18) is in a right triangle structure.

4. A portable waterproof paint filter pressing device according to claim 3, wherein the top of the scraping plate base is provided with a plurality of clamping holes (20) at equal intervals along the length direction, the bottom of the scraping plate (18) is fixedly provided with clamping pins (19) corresponding to the positions of the clamping holes (20), and the clamping pins (19) are clamped in the clamping holes (20).

5. The portable waterproof coating filter-pressing device according to claim 4, wherein the power component of the cleaning mechanism comprises a first nut (25) arranged on one side of the scraping plate base, the first nut (25) is arranged in the inner wall of the waterproof coating filter-pressing box (10), a first screw (24) horizontally rotatably arranged in the box wall of the waterproof coating filter-pressing box (10) is connected in a threaded manner in the middle of the first nut (25), one end of the first screw (24) is rotatably connected in the waterproof coating filter-pressing box (10) through a bearing, the other end of the first screw is connected with a first servo motor (26), a slideway is formed in the box wall of the waterproof coating filter-pressing box (10) corresponding to the first screw (24), and a phase guiding device for limiting the rotation of the first screw is arranged on the first nut (25).

6. The portable waterproof paint filter pressing apparatus as claimed in claim 5, wherein the filter plate top loosening mechanism (17) comprises a loosening plate with the same length as the width of the filter plate (11), a plurality of loosening rods (21) are elastically arranged on one side of the loosening plate facing the filter plate (11) at equal intervals along the length direction, and the bottom ends of the loosening rods (21) are in non-contact connection with the top of the filter plate (11).

7. The portable waterproof coating filter-pressing equipment according to claim 6, wherein the loosening mechanism power assembly comprises an elastic connecting piece arranged on one side of the conveying plate, a second nut (28) is connected to the end portion of the elastic connecting piece, a second screw (27) arranged in the inner wall of the waterproof coating filter-pressing box (10) is connected to the middle portion of the second nut (28) in a threaded manner, one end of the second screw (27) is connected to a second servo motor (29), the other end of the second screw is connected to the inner wall of the waterproof coating filter-pressing box (10) in a rotating manner through a bearing, a phase guiding device for limiting rotation of the second screw is arranged on the second nut (28), a roller (30) is arranged on the other side of the loosening plate, a wavy track (31) is formed in the inner wall of the waterproof coating filter-pressing box (10) corresponding to the roller (30), and the roller (30) rolls along the wavy track (31).

8. The portable waterproof paint filter pressing device according to claim 7, wherein the elastic connecting piece comprises a buffer rod (32) connected to one side of the second nut (28), one end of the buffer rod (32) facing the loosening plate is elastically connected with a second spring (34), the end of the second spring (34) is connected to the loosening plate, a buffer cavity (33) is arranged on the loosening plate outside the second spring (34), the second spring (34) is arranged in the buffer cavity (33), and when the second spring (34) is in a free state, the control roller (30) is in contact with the concave part of the wavy track (31).