94results about "Work manipulation" patented technology

The utility model discloses a high-speed wire rod air cooling roller way roll shape adjusting device which comprises a bottom frame, a plurality of sets of roller seats are arranged at the top end of the bottom frame, a plurality of sets of roller shafts are arranged in the roller seats, driving motors are arranged at the bottom ends of the roller seats, one ends of the driving motors are in transmission connection with the roller shafts, and adjusting structures are arranged at the front ends of the driving motors. Adjusting devices are arranged on one sides of the roll shafts on the two sides, side edge fine adjusting devices are arranged on the two sides of the roll seat, driving can be conducted in the mounting frame by controlling the multiple sets of air rod structures, a baffle is driven to move up and down through a blocking head structure, the advancing direction of a wire rod is blocked and dredged, and the position distribution of the wire rod on the roll shafts can be changed; deviation caused by a spinning drop point and a conveying device during roller way transportation is reduced, the phenomenon that a roll type is prone to layer staggering after roll collection is avoided, the quality of finished products is improved, the position of the baffle can be adjusted at the top end of the roller shaft, the advancing direction of a wire rod is adjusted and changed in cooperation with an adjusting structure, and the effect of changing the drop point is achieved.

The invention relates to the technical field of plate roughing mills, in particular to a plate roughing mill with a feeding and discharging structure, which comprises a bottom plate, a shell is mounted at the top of the bottom plate, two rollers are mounted in the shell, an automatic feeding mechanism and an automatic discharging mechanism are respectively arranged on two sides of the shell, and the automatic feeding mechanism comprises a plurality of upright posts; two moving plates are arranged between the multiple stand columns, multiple feeding rollers are installed between the two moving plates, a limiting mechanism is arranged above the multiple feeding rollers, and a driving mechanism is further arranged between the two moving plates. According to the metal plate rough rolling device, in the process that the feeding roller automatically feeds a metal plate, the two sides of the metal plate can be pushed through the arranged limiting mechanism, and the deviation rectifying effect is achieved, so that the metal plate can be located in the middle of the two rollers to be roughly rolled in the process that the metal plate enters the shell; the rough rolling accuracy of the two rollers on the metal plate is improved, and then the rough rolling quality of the metal plate is improved.

The utility model provides a material turnover device of a steel pipe cold-rolling mill. The material turnover device comprises a first rotating cylinder, a supporting sleeve and a guide sleeve, the first rotating cylinder is provided with an accommodating hole penetrating in the axial direction; the supporting sleeve is fixed to the end of the first rotating cylinder, a groove is formed in the supporting sleeve, the groove is sleeved with the containing hole, and a through hole is formed in the bottom of the groove; the guide sleeve is detachably fixed in the groove and provided with a rectangular hole penetrating in the axial direction of the first rotating cylinder, and the rectangular hole communicates with the penetrating hole. The utility model further provides a two-roller steel pipe cold-rolling mill which comprises the steel pipe cold-rolling mill material turnover device, a first roller, a second roller and a second rotating cylinder. The first rotating cylinder and the second rotating cylinder are oppositely arranged in the axial direction, and the first roller and the second roller are oppositely arranged between the first rotating cylinder and the second rotating cylinder and located on the two sides of the axial extending direction respectively. According to the two-roller steel pipe cold rolling mill, 180-degree overturning of round-to-rectangular materials can be achieved, and then continuous production can be achieved.

The utility model discloses a device for improving the quality of the inner surface of a hot-rolled seamless steel pipe, which comprises a track filling device, the track filling device comprises a transportation track and a movable filling device arranged on the transportation track, the filling device is a movable mechanical arm, the track filling device is adjacent to a secondary punching device, and the secondary punching device is connected with the transportation track. The tubular billet perforated by the secondary perforating equipment is transferred to the tubular billet rotating device through the transferring device, the tubular billet rotating device is arranged on the borax blowing station, and the tubular billet rotating device of the borax blowing station comprises two or more sets of rotating carrier rollers used for supporting the tubular billet to rotate on the rotating carrier rollers. A borax nozzle is arranged at the rear upper position of the middle side of the two rotating carrier rollers on the outer side, a rotary arm is further arranged on the outer side of the borax injection station, and a conveying driving device is arranged on the side close to the rotary arm.

The invention relates to the technical field of angle steel production, and particularly discloses an automatic angle steel machining production line which comprises a heating mechanism, a feeding mechanism and a discharging mechanism. The forming mechanism is used for rolling the blank and rolling the blank with the rectangular section into the angle steel with the L-shaped section; the shearing mechanism is used for cutting off the formed angle steel; the cooling mechanism is used for intermittently conveying the cut angle steel; and the overturning mechanism is used for overturning the angle steel in the conveying process. According to the angle steel production line, the working procedures of heating, forming, shearing, cooling, overturning and the like are integrated, full-process automation of angle steel production is achieved, the problems of low efficiency and high manual dependence degree caused by traditional sectional type production are solved, the production efficiency is improved, and the labor intensity is reduced.

The invention relates to the technical field of rolling, in particular to a steel plate rotating device for angular rolling of a medium-thickness plate and a using method of the steel plate rotating device, and high-precision angular rotation of a steel plate is achieved through the linkage design of a longitudinal lead screw transmission module and a transverse lead screw transmission module in combination with a cam-spring reset structure of a hydraulic push rod assembly and feedback of an angle sensor. The device is simplified in structure, high in adaptability and capable of remarkably improving the rolling efficiency and the plate shape quality.

The invention discloses a slab rotation and centering control method, which comprises the following steps that: at least two cross beams which move in a direction perpendicular to the rolling direction are arranged at the bottoms of steel rotating roller ways in front of and behind a rolling mill, and the cross beams can move up and down; after the plate blank enters the steel rotating roller way, a side guide plate is adopted for centering the plate blank; after centering of the plate blank is completed, at least two steel rotating cross beams are determined in the cross beams according to the physical parameters of the plate blank to conduct steel rotating on the plate blank; the physical parameters at least comprise size parameters of the plate blank; when steel rotating is conducted on the plate blank, the steel rotating cross beam is lifted upwards to support the plate blank, then the steel rotating cross beam is controlled to move by a preset distance in the direction perpendicular to the rolling direction, and therefore the plate blank is driven to rotate by a target angle. Large-angle angular rolling steel rotating can be achieved, meanwhile, the production efficiency of angular rolling broadening and transverse rolling broadening is improved, and the product quality is guaranteed.

The present invention provides a swing-lifting spring-damping gravity billet tilter. The sliding spiral cam adjustment mechanism is connected to the variable four-link swing mechanism, and the swing power mechanism is connected to the variable four-link swing mechanism. The lifting power mechanism is respectively connected to the variable four-link swing mechanism and the adjustable tensioning sprocket lifting mechanism. The lifting power mechanism is used to provide power for the adjustable tensioning sprocket lifting mechanism. The adjustable tensioning sprocket lifting mechanism is arranged on the column and is connected to the gravity spring tilting mechanism. This swing-lifting spring-damping gravity billet tilter can perform a 90° flip on the high-temperature billets discharged from the heating furnace of the section / bar hot rolling production line before rolling, meet the on-site rolling deformation process requirements, can remove the overheated iron oxide on the surface of the billets, improve the surface appearance quality of the rolled materials, increase the on-site production rhythm, and reduce process failures.

The invention provides an intelligent steel transfer control method and system for a thick plate production line. The method comprises the following steps: acquiring standard data of a rough rolling link of the thick plate production line and acquiring a standard image in a steel transfer area through image acquisition equipment; inputting the standard image into the target detection model, and outputting feature data; inputting the standard data and the characteristic data into a rotating speed prediction generation model, and outputting a rotating speed control curve of the steel rotating roller way; and a steel rotating request signal in the rolling process state data is extracted, a control command and a rotating speed given instruction of a steel rotating roller bed are generated according to the rotating speed control curve, and the steel rotating roller bed is controlled to drive the intermediate billet to rotate according to the rotating speed control curve. The rotating speed control curve is generated by extracting the standard data and the characteristic data in the rolling process state data, the steering command and the rotating speed given command are generated based on the rotating speed control curve, the steel rotating roller way is driven to operate according to the commands, and the problems that manual steel rotating is low in precision, lagged in response and low in efficiency are solved.

A tipping device suitable for a steel coil comprises a turning part, a first turning plate, a second turning plate, an arc face lifting part and a side face positioning part. One end of the first turning plate is connected with one end of the second turning plate, and a combined body of the first turning plate and the second turning plate is L-shaped; the cambered surface lifting part is arranged on the second turning plate, and the side surface positioning part is arranged on the first turning plate; and a combined body of the first turning plate and the second turning plate is arranged on the turning part. According to the utility model, the overturning efficiency of the steel coil is improved, and the abrasion on the surface of the steel coil is reduced as much as possible in the overturning process.

The invention belongs to the technical field of wire rolling, and particularly discloses a rod and wire rolling method for eliminating steel billet corner defects and a rolling mill stand. The method comprises the following steps that firstly, a heated steel billet is conveyed to a steel rotating device; then the steel billet enters a steel rotating roller way under the action of a guide and guard guide plate, the steel billet is rotated by 45 degrees through a steel rotating device, and the corner of the steel billet is aligned with a groove hole in a roller; then the steel billet is conveyed to a rolling mill through a conveying roller way and a V-shaped anti-torsion guide roller; and finally, the steel billet is rolled into a steel bar through seven passes of rough rolling, wherein large deformation is adopted in the first pass. In order to solve the problem of residual crack defects in billet corner rolling, a pass system is optimized, and the mode that upper and lower flat rollers and left and right vertical rollers are used for simultaneous pressing-down rolling in four directions is adopted, so that the problems that in the continuous casting process, due to the fact that the billet corner cooling speed is higher than that of other parts, shrinkage is uneven, and tensile stress is generated on the surface are solved; therefore, cracks are generated at the corners of the steel billets, and the product quality is influenced.

The utility model discloses a steel ingot turnover mechanism for a rolling mill, which belongs to the technical field of steel ingot rolling and comprises a first vertical plate and a second vertical plate, a conveying roller is rotatably arranged between the first vertical plate and the second vertical plate, an electric push rod is fixed on the front side of the second vertical plate, a sliding seat is fixed at the output end of the electric push rod, and a plurality of groups of turnover components are arranged on the sliding seat. A knocking mechanism is arranged above the overturning assembly and comprises a sliding rod, a mounting plate is fixed to the rear end of the sliding rod, a knocking hammer is fixed to the rear side of the mounting plate, a baffle is fixed to the front end of the sliding rod, a spring is fixed between the baffle and the second vertical plate, and the knocking mechanism further comprises a power assembly. After the steel ingot is overturned to be in a vertical blank state, the baffle is driven by the power assembly to move forwards, then the baffle is released, the baffle drives the sliding rod to drive the mounting plate and the knocking hammer to rapidly move backwards under the action of the elastic force of the spring, the steel ingot is knocked, the steel ingot vibrates, slag crust on the surface of the steel ingot is knocked off, and the quality of the rolled steel ingot is guaranteed.

The application discloses a graphite cladding device for an inflation evaporator aluminum plate inflation pipeline, which comprises an oven, a clamping assembly, a turnover assembly, a pushing assembly, a rotating assembly, a positioning assembly and a cladding assembly. The oven is used for drying and transmitting the first and second raw aluminum plates in sequence to the rotating assembly. The rotating assembly comprises a rotating roller, one side of the rotating roller is provided with a follow-up roller, and the two ends of the rotating roller are fixedly connected with inclined baffles. The follow-up roller rotates around the rotating roller as an axis to form state one and state two. The side of the rotating roller away from the oven is provided with a driving roller. The follow-up roller and the driving roller are on the same vertical line when in state one. The pushing assembly is arranged on the lower side of the rotating assembly. The first raw aluminum plate after drying first contacts the inclined surface of the inclined baffle in state one and moves to fall on the pushing assembly. The application realizes the automatic cladding function conveniently and efficiently.

This invention belongs to the field of metallurgy and rolling technology, specifically relating to a high-strength, high-toughness, low-temperature resistant hot-rolled H-beam for floating oil storage and transportation vessels and its preparation method. Its chemical composition by weight percentage is: C: 0.07–0.11%, Si ≤ 0.2%, Mn: 1.5–1.9%, V: 0.06–0.10%, Nb: 0.02–0.05%, Ni: 0.1–0.4%, B: 0.001–0.002%, Alt: 0.025–0.045%, P ≤ 0.015%, S ≤ 0.006%, N: 0.01–0.015%, O ≤ 0.003%, with the remainder being Fe and unavoidable impurities. This invention's H-beam is based on green and environmentally friendly principles, emphasizing lightweight technology. It reduces the overall transportation cost of floating vessels, improves material utilization efficiency, and achieves a 15–30% weight reduction target for the floating oil storage and transportation vessel structure. It provides product and technical support for steel structures used in some hull modules.

The invention relates to the technical field of roll forging of aluminum alloy bars, in particular to roll forging equipment for aluminum alloy bars, which comprises a roll forging device, a driving structure and a clamping structure. The upper end of a first base in the roll forging device is connected with a first telescopic base and a second telescopic base through bolts; one side of the second telescopic base is connected with a first rotating disc through a coupler, the outer side of the first rotating disc is movably connected with a first belt, one side of the first belt is movably connected to the outer side of a fourth rotating disc in the driving structure, and an electric telescopic rod can be protected by connecting a first connecting rod between a first connecting piece and a second connecting piece; the electric telescopic rod can be movably connected with the second telescopic rod through the telescopic cylinder, and can be connected with the clamping jaw through the second telescopic rod, so that the electric telescopic rod can drive the clamping jaw to clamp when the second telescopic rod stretches out and draws back, and a connecting ring connected with a third connecting piece is used for limiting the rear end of the clamping jaw.

The utility model discloses an automatic casting blank overturning device which comprises a material preparation frame, a material feeding device, a material discharging device, a material feeding device and a material discharging device, wherein the material preparation frame is provided with a working table top for overturning a milling surface pipe; the bumping post device is movably arranged on the material preparation frame and is used for preventing the milling surface pipe from automatically overturning and descending; and the stopper device is movably arranged on the material preparation frame and is used for assisting and stopping the milling pipe from automatically overturning and descending. The utility model has the beneficial effects that: single milling surface pipe material preparation is realized, and the labor intensity of workers is reduced through automatic overturning; and the operation risk that people are squeezed and injured in the overturning operation process is avoided.

The utility model discloses an automatic steel transfer conveying system of a roller bed before rough rolling, which comprises a rack and a rotary roller bed group, a motor group is arranged outside one side of the rack, and a cleaning component is arranged below the bottom of the rack and at a position corresponding to the rotary roller bed group. According to the utility model, through the three groups of motors in the motor group, the three No.1 motors control the three No.1 rotary rollers to rotate forwards, and the three No.2 motors control the three No.2 rotary rollers to rotate backwards and then rotate forwards, the combined motion mode can utilize the special structures and different rotation directions of the rotary rollers, so that the rotation efficiency is improved; compared with the prior art, the steel rotating device has the advantages that hot billet steel can quickly and accurately rotate by 90 degrees on the rotating roller way, steel rotating time is greatly shortened, the production rhythm is improved, and the first infrared sensor, the second infrared sensor and the third infrared sensor arranged above the rack can detect the position and the state of a slab.

The invention provides a method for improving the core quality of bearing steel, which specifically comprises the following steps of: (1) controlling the number of cogging rolling passes to be 9 when the bearing steel is produced; and (2) in the first five passes of cogging rolling, at least three passes adopt a high-pressure rolling mode with the reduction rate being larger than or equal to 20%. According to the method, the rolling process is optimized, the rolling reduction rate is improved by low times, the bearing super-superior level is achieved, and the bearing steel quality is improved.

The invention relates to the technical field of metallurgical equipment, in particular to a rotary feeding mechanism of a cold pilger mill, which comprises a mounting frame and a movable frame, a positioning ball is movably arranged in the mounting frame, the outer surface of the positioning ball is tightly attached to the outer surface of a pipe blank, and a detection control assembly is arranged in the movable frame. The compensation rotation unit is arranged on the mounting frame and is used for enabling the detection control assembly to control the compensation rotation unit to work after the positioning ball is matched with the detection control assembly to detect the slipping phenomenon at the position, and then compensation is carried out; according to the rotary feeding mechanism of the cold pilger mill, when the arranged positioning ball makes contact with a pipe blank which is not rolled, the detection control assembly is in a non-working state, after the rotary device and the feeding device are started, the positioning ball can move along with the pipe blank, at the moment, the detection control assembly can rapidly detect abnormal conditions, and the situation of secondary reworking of the pipe blank is effectively reduced.

The present application relates to a kind of wide and thick plate product circulation efficiency promotion system and process, system includes: hot cutting roller, hot cutting section, cooling bed, shear line, first plate turnover machine, detection module, shear second line, extension roller, detection module is set on shear line, by newly adding extension roller on shear second line, make shear second line form first path and second path, shear line and shear second line carry out sampling inspection to wide and thick plate, the sampling inspection wide and thick plate that flows into shear line is turned over by first plate turnover machine, it does not belong to the direct circulation of sampling inspection wide and thick plate, the wide and thick plate that flows into shear second line belongs to the sampling inspection wide and thick plate is turned over by second plate turnover machine on second path, it does not belong to the direct circulation of sampling inspection wide and thick plate by first path extension roller.This application has improved the finishing logistics efficiency of wide and thick plate, reduced the turnover frequency of wide and thick plate, thereby reduce the scratch on the surface of wide and thick plate due to plate turnover machine, avoid leading to product quality problem, and the beneficial effects of cost reduction and efficiency improvement.

To provide a steel material transfer device which is effective for transferring a steel material with a higher degree of freedom.SOLUTION: A steel material transfer device 10 includes: a carriage 111 reciprocating along a horizontal circular orbit 114 between a carry-in position where a steel material 9 having a longitudinal direction LD is carried in in a state where the longitudinal direction LD is in a first horizontal direction, and a carry-out position where the steel material 9 is carried out in a state where the longitudinal direction LD is in a second horizontal direction crossing the first direction; an arm 14 provided on the carriage 111 so as to swing around a horizontal base axial line 141 crossing the circular orbit 114; a saddle 15 connected to the end of the arm 14 so as to swing around an end axial line 151 parallel to the base axial line 141; and a driving device 20 for driving the carriage 111, the arm 14 and the saddle 15 so as to arrange the saddle 15 at a receiving position P21 where the steel material 9 is received from the carry-in position, and delivery positions P31, P32 and P33 where the steel material 9 is delivered to the carry-out position.SELECTED DRAWING: Figure 3

The invention relates to a device (1) for turning plate-shaped components (2), comprising: - a rotating unit (3) in order to turn a component (2) with respect to a rotational axis (R) during a turning process; and - a conveyor unit (4) which is received in the rotating unit (3) and which can be rotated by means of the rotating unit (3), said conveyor unit (4) comprising at least one first conveyor means (5) and a second conveyor means (6) arranged opposite the first conveyor means, wherein a first conveyor plane (7) is defined by the first conveyor means (5), and a second conveyor plane (8) arranged parallel to the first conveyor plane (7) is defined by the second conveyor means (6). The conveyor unit (4) is designed to receive the component (2) between the first and second conveyor plane (7, 8) such that the component (2) is received between the first and second conveyor means (5, 6) for the turning process. At least one of the two conveyor means, comprising the first and second conveyor means (5, 6), is designed to be movable with respect to the conveyor plane thereof along a conveyor direction (F).

The utility model discloses a waste box device applicable to a high-speed area of high-speed bars, which is mounted on a fixed base at the rear end of a modular rolling mill and comprises a waste box base, a waste box cover and a red steel guide groove. The multiple waste box covers are all rotationally connected with the waste box base, and the red steel guide groove is fixedly formed in the waste box base. The red steel guide groove comprises a guide groove base, a turning plate guide groove, a back flushing module and a circular guide groove, the turning plate guide groove and the circular guide groove are fixedly installed on the guide groove base, the guide groove base is fixedly connected with the waste box base, one end of the turning plate guide groove is communicated with a module rolling mill, and the other end of the turning plate guide groove is communicated with the back flushing module. The other end of the turning plate guide groove is communicated with the reverse blowing module, the reverse blowing module is communicated with the circular guide groove, and the rolling mill has the advantages that the rolling mill is protected, the manual cleaning frequency is reduced, the labor intensity is reduced, and the like.

The utility model discloses a tilting gear which comprises a tilting frame used for placing a steel coil; the tipping hydraulic cylinder is used for driving the tipping frame to turn over by 90 degrees, so that the steel coil is turned over from a horizontal coil to a vertical coil or turned over from the vertical coil to the horizontal coil; the clamping device comprises a pair of clamping mechanisms which are fixedly installed on the two sides of the tipping frame respectively, any clamping mechanism comprises a clamping hydraulic cylinder and an arc-shaped support, each arc-shaped support comprises an arc-shaped plate, a third pin shaft and a rotating arm, the arc-shaped supports are rotatably installed on the two sides of the tipping frame through the third pin shafts, the arc-shaped plates are provided with arc inner surfaces, and the rotating arms are arranged on the arc-shaped plates. And the arc-shaped support is hinged to the third pin shaft, cylinder barrels of the clamping hydraulic cylinders are rotationally installed on the two sides of the tipping frame, one end of the rotating arm is hinged to the third pin shaft, and the other end of the rotating arm is hinged to the telescopic end of each clamping hydraulic cylinder. According to the overturning device, the steel coil is clamped in the overturning process through the clamping device, and the horizontal coil can be stably overturned into the vertical coil when the steel coil overflows.

The invention relates to a production process for rolling round steel through a universal mill, and belongs to the technical field of steel ingot pouring equipment in the metallurgical industry. According to the technical scheme, a blooming mill BD, a universal mill UR, a torsion mill E and a universal mill UF are included, in the rough rolling stage, a rectangular intermediate billet is rolled through a box-shaped hole in the BD mill, and after rolling, the rectangular intermediate billet is overturned by 90 degrees through a tilting gear to enter a finish rolling area; in the finish rolling stage, a head universal rolling mill and a tail universal rolling mill (UR and UF) and a middle torsion rolling mill (E) are used for continuous rolling one pass to obtain a finished product, the UR rolling mill is used for rolling a flat hexagonal cross section through a hexagonal universal pass, the cross section is twisted by 90 degrees before a rolled piece enters an inlet guide of the UF rolling mill, the UF rolling mill is used for finish rolling forming through a round universal pass, and finally high-precision rolling of the round steel is achieved. The universal rolling mill has the beneficial effects that large-specification round steel can be rolled and formed on the universal rolling mill in the vertical direction and the horizontal direction at the same time, and the size precision of the round steel is guaranteed.

The present application relates to the technical field of profile steel conveying, in particular to a forklift gantry profile steel diverging guiding device, which comprises a guiding support mechanism, a fixed-point transposition mechanism arranged on the guiding support mechanism, a profile steel width adapting mechanism arranged on the fixed-point transposition mechanism, and four sets of assisting mechanisms arranged on the profile steel width adapting mechanism; the guiding support mechanism comprises a crossbeam, a base mounted inside the crossbeam, and a bottom rail mounted inside the base. By arranging an independent guiding support mechanism on the existing steel conveying system, and arranging a fixed-point transposition mechanism on the guiding support mechanism, the profile steel is precisely clamped by the fixed-point transposition mechanism cooperating with the profile steel width adapting mechanism and the four sets of assisting mechanisms. After the clamped profile steel is rotated and lifted upward at the fixed-point position, the profile steel can be precisely put into the next conveying equipment, thereby avoiding larger angle deviation of the profile steel after being divergently guided to the next conveying system.

The present invention discloses a device and an operation method for realizing the rotation function by OAL, including a bottom plate, a cold-rolled product channel, and an adjustment component. It is characterized in that: a furnace grate and a zinc pot are arranged on the bottom plate, the bottom end of the furnace grate abuts against the top end of the zinc pot, a galvanized product channel is arranged above the zinc pot, a cold-rolled product channel is arranged on one side of the galvanized product channel, and the adjustment component includes an electric hoist and a transition connection channel; the output end of the electric hoist is connected to the transition connection channel through a traction rope, a transfer channel is arranged at one end of the cold-rolled product channel close to the galvanized product channel, and one end of the transition connection channel is rotationally connected to the cold-rolled product channel through a rotating shaft. The present invention adjusts and rotates the position of the transition connection channel by installing an adjustment component and an electric hoist. The transition connection channel rotates around the rotating shaft to the required position through the electric hoist or its own weight, realizing the rapid and safe switching of the product channel.

The utility model discloses a rocker arm frame device for a feeding slewing mechanism of a seamless steel tube cold-rolling mill. The rocker arm frame device comprises a rocker arm frame and a rocker arm crank throw, the frame body is defined by a front end plate, a rear end plate and two side plates, a concave portion is arranged in the middle of the frame body, a first pin shaft and a second pin shaft are arranged on the two sides of the concave portion, the two side plates serve as the first side plate and the second side plate, the two ends of the two pin shafts are located on the two side plates respectively, the first pin shaft is close to the side of the front end plate, and a first through hole is formed in the front end plate. The rocker crank consists of two clamping plates and a connecting plate for connecting the two clamping plates; the inner side distance of the two clamping plates is greater than the outer side width of the two side plates; the two clamping plates are clamped outside the two side plates and connected through a first pin shaft, the connecting plate is located on the outer side of the front end plate, and a second through hole corresponding to the first through hole is formed in the connecting plate; a bolt is further included, the head of the bolt is limited to the inner side end of the front end plate, a bolt rod body is inserted from the first through hole and extends out of the connecting plate after passing through the second through hole, a stop piece is arranged on the extending section, and a compression spring is arranged on the bolt rod body between the stop piece and the second through hole.