112results about How to "Change the tightness" patented technology

A sealing assembly including a sealing component and a structural member. The sealing component has a first surface structure. The structural member has a second surface structure. A portion of the second surface structure is in contact with at least a portion of the first surface structure. The first surface structure and / or the second surface structure is a nano-textured surface. Interaction of the first surface structure with the second surface structure dynamically reduces friction, leakage of a fluid, and / or wear between the sealing component and the structural member.

The invention discloses a hand rehabilitation device for interventional radiology department stroke patient nursing, which comprises a frame body, the inner side of the frame body is provided with a rotating ring, the inner side of the rotating ring is provided with a training device, and the middle position of the front end surface of the training device is rotatably connected with an adjusting button. According to the hand rehabilitation device for interventional radiology department stroke patient nursing, the rotating ring, the training device and other structures are arranged, when rehabilitation treatment is carried out on some stroke patients, five fingers of a patient only need to be respectively inserted into the upper placing hole and the lower placing hole, a telescopic column and a second spring are arranged on the training device, the patient pulls the placing holes, through the connecting columns on the two sides of the training device and the training device rotationallyconnected into the rotating ring, the training device is driven by the connecting columns and the rotating ring to rotate in the frame body, the wrist movement capacity of the patient is exercised, and the effect of effectively conducting rehabilitation training on the patient is achieved.

The invention relates to the field of doors, and discloses a waterproof safety door. The waterproof safety door comprises a door frame and a door sash; an adjustable sealing mechanism is arranged between the door frame and the door sash; the adjustable sealing mechanism comprises a waterproof groove annularly formed in the door sash, a mounting groove formed in the door sash and corresponding to the waterproof groove, an adjusting ring arranged in the mounting groove and locally extending out to insert in the waterproof groove or totally shrinking into the mounting groove, and an elastic airbag arranged between the inner wall of the mounting groove and the adjusting ring; the extension and the shrinkage of the adjusting ring are controlled by a first driving mechanism; the inflation or thedeflation of the elastic airbag is controlled by a second driving mechanism; and after the door sash is closed, the first driving mechanism drives the adjusting ring to extend into the waterproof groove, and the second driving mechanism drives the elastic airbag to expand for interference fit with the waterproof groove. The waterproof safety door maintains an indoor ventilation state in daily life; and if water is accumulated, a sealing state can be maintained between the door sash and the door frame through the structure to prevent the accumulated water from entering indoors, so that the structure is skillful, the door opening and closing power is saved, and the waterproof effect is excellent.

The invention discloses an intelligent induction adjusting helmet for an AR all-in-one machine. The intelligent induction adjusting helmet comprises an AR head display, two head belts, a fixed frame and an adjusting assembly; one ends of the two head belts are symmetrically fixed on one side of the AR head display, and the other ends are connected with the adjusting assembly; one end of the fixedframe is fixed with the top of the AR head display, and the other end is fixed with the adjusting assembly; a supporting assembly is fixed at the bottom of the adjusting assembly; the supporting assembly is composed of a lifting part, a connecting block, two supporting frames and a shoulder pad plate, wherein the top of the lifting part is fixed with the adjusting assembly, and the bottom of the lifting part is in sliding connection with the connecting block; the two supporting frames are symmetrically distributed on the two sides of the connecting block; the supporting frames and the shoulderpad plate are additionally arranged under the AR head display, so that the shoulder is used for bearing a part of the weight, and pressure of cervical vertebra is reduced, the wearing is more comfortable, and the helmet can be well worn by a user by adjusting the head belts through the adjusting assembly, thereby adjusting the tightness of the head belts in an intelligent induction mode.

The invention discloses a double-scraper diaphragm butterfly valve. The double-scraper diaphragm butterfly valve is characterized in that a valve body, a support and an execution mechanism are included, and the support and the execution mechanism are sequentially connected with the valve body; a butterfly plate is arranged in the valve body; a tetragonal-prism-shaped groove ring lug and a cylindrical groove ring lug which are parallel to the plane of the butterfly plate are arranged above and below the rear end of the butterfly plate; a tetragonal-prism-shaped upper valve rod is arranged in the tetragonal-prism-shaped groove ring lug; a cylindrical lower valve rod is arranged in the cylindrical groove ring lug; the butterfly plate is further connected with a sealing structure, and the sealing structure comprises a valve seat pressing plate, a valve seat, a diaphragm ring, a pressing plate ring, a butterfly plate sealing pad, a front pressure cavity and a rear pressure cavity; and a diaphragm front end thrust groove, front through-flow holes and pressing plate bolt holes are formed in the pressing plate ring. The elastic diaphragm pressure self-sealing structure is adopted, the diaphragm front end thrust groove and a diaphragm rear end thrust face achieve the function of scrapers, and special connection of the upper valve rod and the lower valve rod and locking prevention are achieved; low twisting force and the small structure are achieved, and compressive resistance is high; and the butterfly valve has the beneficial effects of being reliable in performance and long in service life.

The invention discloses an aluminum electrolytic cell closed gas collecting device. At least two electrolytic chambers are formed inside an aluminum electrolytic cell through an anode and a cathode; the anode is a self-baking anode, and an anode paste discharging system is arranged above the anode; three groups of flue gas gathering pipelines are arranged on the aluminum electrolytic cell, the first-stage flue gas gathering pipeline directly communicates with an inner space of a cell body, the second-stage flue gas gathering pipeline extends to the position, above the anode, inside the cell body, and the third-stage flue gas gathering pipeline extends into the cell body and is in butt joint with an anode paste feeding port in the top of the self-baking anode through the anode paste discharging system; and the aluminum electrolytic cell is provided with a two layers of sealing structures including the outer sealing structure and the inner sealing structure. By means of the aluminum electrolytic cell closed gas collecting device, the centralized treatment and recovery of the exhaust gas and the waste heat generated by the aluminum electrolytic cell adopting the multiple continuous operation chambers are realized, the ultra-low controllable discharge of air pollutant in the electrolytic cell is realized, the heat preservation state of the electrolytic cell is improved, the heat loss of the electrolytic cell is reduced, and the energy efficiency level of the electrolytic cell is effectively increased.

The invention relates to the technical field of wire and cable production equipment, in particular to an adjustable wire and cable pay-off device. The adjustable wire and cable pay-off device comprises a supporting shaft; a rotating shaft is fixedly connected with one end of the supporting shaft, and is rotationally connected to a supporting plate; a plurality of evenly arranged tight ejecting plates are arranged in the peripheral direction of the supporting shaft, and are arranged in the length direction of the supporting shaft; a plurality of outer barrels are arrayed on the supporting plate along the circumference; the ends, close to the supporting shaft, of the outer barrels are provided with push rods; the face, away from the supporting shaft, of the supporting plate is provided with a threaded barrel; one end of the threaded barrel is fixed to the supporting plate; the other end of the threaded barrel is sealed through a threaded cover; the threaded barrel, the threaded cover and the supporting plate form a sealed gas cavity; and the ends, away from the push rods, of the outer barrels are communicated with the gas cavity through through holes. The adjustable wire and cable pay-off device is simple in structure and convenient to use, the pay-off tightness degree is changed by means of the gas pressure principle, and the wire and cable machining procedure is greatly improved.

The invention discloses a correctable automatic adjustment double-plug linkage liquid leakage prevention exhaust valve. The valve comprises a valve body, an upper-stage cavity and a lower-stage cavityare formed in the valve body, a piston pipe is installed at the upper end of the valve body in a sealed and threaded mode, and the lower end of the piston pipe extends into the upper-stage cavity andis provided with a synchronous pipe in a sealed and sliding insertion mode. The synchronous pipe sleeves a sealing plug, and the lower end of the synchronous pipe extends into the lower-stage cavityand is provided with a floating ball plug. Linkage sealing is achieved through the sealing plug and the floating ball plug under the action of the synchronous pipe, the liquid leakage degree is sensedthrough a pressure regulating floating ball, and a pressure regulating air hole is opened through a piston column to release high-pressure gases in the floating ball plug into the upper-stage cavityto restrain rising of the liquid level and increase buoyancy of the floating ball plug. Reinflation correction reuse is achieved through the piston pipe and a one-way inflation nozzle, the service life of the exhaust valve is prolonged, the liquid leakage prevention effect is improved, the liquid conveying cost is saved, and resource waste is avoided.

The invention discloses an on-line detecting and sorting device for defects of stamping parts. The on-line detecting and sorting device comprises an outer shell body, a conveying mechanism, a visual inspection mechanism and an inferior-quality product classification executing mechanism, an installation station used for installing the conveying mechanism is arranged on the outer shell body, the visual inspection mechanism is arranged on the upstream of the outer shell body and used for carrying out image processing on to-be-detected stamping parts, and the inferior-quality product classification executing mechanism is arranged on the outer shell body and on the downstream of the conveying mechanism, and is used for receiving an instruction from the visual inspection mechanism, a processor sends the instruction to a inferior-quality product classification mechanism according to a machine vision algorithm, and the stamping parts passing through the visual inspection mechanism enter two recovery boxes along a classification guide plate correspondingly to complete detection and sorting of the stamping parts. According to the on-line detecting and sorting device for the defects of the stamping parts, the stamping parts with the defects can be effectively detected, sorting can be carried out on the stamping parts, and therefore the manpower can be saved, the production speed can be increased, the detection efficiency can be improved, and the device is particularly suitable for detecting and sorting small stamping parts.

The invention discloses a hydraulic locking device for flexible seal of a conical surface. The hydraulic locking device comprises a first blank cover, a shell, a first hydraulic control one-way valve core, a second hydraulic control one-way valve core, a second blank cover and a reset spring. The hydraulic locking device is capable of realizing high-reliability flexible seal of the conical surface; the valve cores are integrally stressed by pressure impact from an actuator so as to realize own balance; by cooperation of the reset spring, a zero offset problem generated because of leakage caused by poor sealing is solved in a locked state, namely in a nonworking process of a thrust liquid oxygen kerosene engine, and the conventional sealing structure and sealing way are changed.

The invention relates to a novel magnetic attraction type wall climbing robot for sand blasting and rust removal of a ship. The robot comprises a walking device, an auxiliary sucker device, a power system and a wall climbing robot frame body. Magnet mounting plates for mounting rectangular permanent magnet blocks are made by stamping, magnet fixing plates are machined in the middle, and the bending resistance can be enhanced so that the rectangular permanent magnet blocks with a large attraction force can be installed without being deformed. An auxiliary sucker system is arranged at the frontend of the wall climbing robot body to increase the attraction torque, so that the anti-overturning capability is improved to adapt to climbing at different negative angles, and the load of the wall climbing robot is increased; an auxiliary sucker adopts permanent magnets and electromagnets for cooperative installation, a certain attraction force can be ensured under the condition of sudden powerfailure, and the power can be cut off when the auxiliary sucker needs to be removed. At the same time, universal wheels are arranged on the front and rear sides to decrease a frictional force during walking, a walking system is provided with spring dampers which automatically expand and retract to change the tightness degree of crawler belts when the robot climbs an obstacle, and therefore a stable attraction state can be maintained.

The invention discloses intrusion detection equipment convenient to mount or dismount. The equipment comprises a shell and a mounting base. A power port is formed in the left side of the front end face of the shell. A plurality of wiring holes are formed in the middle of the front end surface of the shell; a data hole is formed in the right side of the front end surface of the shell; an open groove is formed in the middle of the upper end face of the mounting base, sleeves are arranged at the four corners of the lower end face of the mounting base, fixing discs are arranged at the bottoms of the sleeves, air suction cups are arranged below the fixing discs, and adjustable fixing blocks are arranged at the positions, corresponding to the sleeves, of the upper end face of the mounting base.According to the intrusion detection equipment convenient to mount or dismount, the mounting base capable of being conveniently fixed is arranged below the shell, the air suction cups are arranged atthe corners of the lower end face of the mounting base, the position of the detection equipment can be fixed through the air suction cups, so that the intrusion detection equipment can be directly fixed to a wall, and mounting and dismounting of the intrusion detection equipment are facilitated.

The invention discloses an anti-seismic support for civil engineering and an assembly method thereof, and relates to the technical field of anti-seismic supports. The anti-seismic support solves the problem that an existing anti-seismic support cannot simultaneously meet the simultaneous support and connection of equipment and pipelines and is inconvenient to adjust and use. The anti-seismic support for civil engineering and the assembly method thereof comprise a support connection mechanism, an equipment connection mechanism is fixedly mounted at one end of the support connection mechanism, two main body support pipes are fixedly mounted on the inner side of the other end of the support connection mechanism, a third spring is arranged on the inner side of one end of each main body supportpipe, one end of each third spring is slidably connected with a length adjustment rod, and one end of each length adjustment rod is provided with a movable connection foot plate. Pipelines are clamped and buffered, support use of pipelines with different sizes and different angles can be effectively realized, meanwhile, equipment connection can be realized, the application range is wider, and thelocking effect is good.

The invention provides a winder and electric equipment with the winder. The winder comprises a rotary shaft, a rotary wheel and a power line. The rotary wheel is rotatably disposed around the rotary shaft. The rotary wheel comprises a peripheral accommodating groove. The power line comprises an inserting end and a wiring end opposite to the inserting end. The power has a complete retraction state and a complete extraction state. In the complete retraction state, the power line completely winds in the accommodating groove. In the complete extraction state, one part, close to the inserting end, of the power line extends out of the accommodating groove. During switching between the complete retraction state and the complete extraction state, the tightness of the power line winding in the accommodating groove changes while the positioning of the wiring end is unchanged. Due to the fact that the wiring end of power line is fixed during extraction and retraction of the power line and only the tightness of the power line is changed, an elastic piece and a contact structure are not needed, and electric safety and reliability of the winder and the corresponding electric equipment can be increased.

The invention discloses an electrician insulating tape processing device with an automatic winding function. The electrician insulating tape processing device comprises a base, the upper end of the left side of the base is fixedly connected with a shell, the left end and the right end of the shell are fixedly connected with supporting strips correspondingly, telescopic rods are rotatably connectedto the inner sides of the supporting strips, the exteriors of the telescopic rods are movably connected with rollers correspondingly, and bare adhesive tape is arranged on the inner side of the shell; and the upper side of the inner surface of the shell is fixedly connected with an adhesive spraying device, a soft brush and a scraper in sequence from left to right, an air-drying fan is arranged on the right side of the scraper and fixedly connected with the upper side of the inner surface of the shell, the upper end of the middle of the base is fixedly connected with an oblique plate, the right side of the oblique plate is fixedly connected with a sectioning device, and a finished product box is arranged on the lower part of the front side of the sectioning device and fixedly connected with the upper end of the right side of the base. The electrician insulating tape processing device has the advantages that adhesive coating rewinding and adhesive tape sectioning processes are integrated, adhesive coating is uniform and flat, coating is saved, and fully-automatic equidistant sectioning is achieved.

The invention discloses a roller micromotion adjusting device of an elasticizer, and belongs to the field of elasticizers. The roller micromotion adjusting device comprises a support frame, a roller,a leather roller and a thread moving device. The roller is connected to the support frame rotationally, the leather roller is connected to the support frame rotationally and abutted against the outerwall of the roller, and the thread moving device slides along the axial direction of the roller. The roller micromotion adjusting device is characterized in that a mounting frame is hinged to the support frame; the leather roller slides along the axial direction of the roller to fit the mounting frame; a linkage rod is connected to the mounting frame rotationally; one end of the linkage rod is connected to the thread moving device detachably, and the other end of the linkage rod is stressed by the thread moving device to drive the leather roller and the thread moving device to slide oppositely. The roller micromotion adjusting device has the advantages that surface utilization rate of the leather roller can be increased, and service life of the leather roller can be prolonged.

The invention discloses an oil scraping device for wastewater treatment. The device comprises a device shell, a motor, a driving roll, a driven roll, a driving belt, an oil scraping belt, an oil scraper and a bracket, wherein the motor, the driving roll and the driving belt are arranged on the device shell; the motor is connected with the driving roll through the driving belt; the driving roll is connected with the driven roll through the oil scraping belt; the device shell is mounted at the upper part of the bracket; the driven roll is fixed at the lower part of the bracket; the oil scraper comprises two scraping blades positioned on the two sides of the oil scraping belt; a knife rest is correspondingly fixed at the bottom of each scraping blade; a distance regulating mechanism is arranged between the two knife rests. The device overcomes the defects that the oil scraping belt and the scraping blades need replacing frequently, and oil contamination is collected not thoroughly.

The present invention relates to an inflatable sealing device, in particular to a movable inflatable sealing device and a method of using the same, the sealing device is installed on a mobile processstation, the mobile process station is connected with the fixed process station through a double linear guide rail, the bottom surface of the inflatable sealing ring is pasted into the sealing ring fixing groove through adhesive tape, the upper surface of the inflatable sealing ring is lower than the sealing ring fixing groove when the inflatable sealing ring is exhausted, and the pulling operation of the mobile process station can be carried out at this time; The inflatable sealing ring expands the upper surface of the sealing ring higher than the height of the sealing ring fixing groove in the inflatable state, so that the sealing effect can be achieved by tightly fitting the sealing sheet metal of the fixing process station. The movable inflatable sealing device adopts the movable inflatable sealing device, which can not only ensure the good sealing effect between the two process stations, but also enable the fixed process station to enter from the mobile process station for good maintenance when the fixed process station fails.

The invention discloses a rapid knitting method for a bond-head ribbon. The method comprises steps as follows: (1) feeding of weft and warp: a weft feeding mechanism feeds weft to a knitting mechanism and a warp feeding mechanism feeds warp to the knitting mechanism; (2) loose knitting of a ribbon part: the knitting mechanism knits the warp and the weft to form the ribbon part; (3) close knitting of a bond head part: the weft feeding speed of the weft feeding mechanism, the warp feeding speed of the warp feeding mechanism and the winding speed of a winding mechanism are decreased, and the knitting mechanism knits the weft and the warp to form the bond head part; (4) fusion cutting. The bond-head ribbon is rapidly knitted once, a bond head gluing procedure is omitted, the method is more environment-friendly, the product structure is more diversified, the production efficiency is greatly improved, the product variety is enriched, the product comfort is improved, bond heads are soft and touch good, the increasingly improved aesthetic standard of people is met, and the functionality and safety of the product are better.

The invention discloses a double-channel metal pipeline joint for cold and hot water mixed flow based on hot expansion and cold rotation. The double-channel metal pipeline joint structurally comprisesan intermediate metal pipe, a hot water inlet pipe, a hot water connecting head, a mixed flow port, a cold water inlet pipe, a cold water connecting head, a threaded water outlet port, a reinforcingnut and a hot expansion and cold rotation tightening device. According to the double-channel metal pipeline joint, through the arrangement of a cold water flow pushing mechanism, rubber rings can be pushed by the pushing force of water flow when cold water is discharged, so that the rubber rings are expanded to be closely attached to water outlet port gaps, and water leakage is prevented when thecold water is discharged; and through a heat expansion tightening ring, water outlet port gaps can be compensated by utilizing the heat expansion characteristic of rubber when hot water is discharged,water leakage is prevented when hot water is discharged, the problem that the rubber rings in joints can only tighten hot water or cold water discharging gaps when the hot water or cold water is discharged because the size is changed as the temperature changes is solved, and the purpose that the tightness of the joints is not changed as the temperature changes is achieved.

The invention relates to the technical field of steel wire ropes, and discloses a marine steel wire rope maintenance device which comprises a base, three supporting rods are fixedly connected to the top face of the base, a lubrication detection cylinder is fixedly connected to the top face of the supporting rod located on the right side, and clamping rings are arranged on the inner walls of the front side and the rear side of the lubrication detection cylinder. The clamping rings are fan-shaped bodies, and the concave faces of the two clamping rings correspond to each other. Through the arrangement of the lubrication detection cylinder, whether lubricating oil needs to be smeared on all positions of a steel wire rope passing through the lubrication detection cylinder again or not is automatically detected by utilizing the friction force change generated by whether the lubricating oil exists on the outer wall of the steel wire rope or not, the problems of waste and inconformity to use requirements due to the fact that excessive lubricating oil is smeared on the portion, still with enough lubricating oil, of the steel wire rope are avoided, and the device has the advantages of integrating detection and maintenance, is quick in response and high in stability and has the advantage of improving the working efficiency compared with an existing common detection mechanism.

The invention discloses the wire dividing device of a plastic flat wire drawing machine group. The device comprises a side plate. The side surface of the side plate is provided with an elastic adjusting structure. The elastic adjusting structure comprises a first chute and a second chute arranged on one side of the side plate. The internal portions of the first chute and the second chute are slidably connected to first slide blocks. The first slide block in the first chute is connected to a first fixed plate through a first electric telescopic rod. The first slide block in the second chute isconnected to the first fixed plate through a second electric telescopic rod. The side surface of each first slide block is connected to a connection plate. By using the wire dividing device of the plastic flat wire drawing machine group, a control switch group controls the work of the first electric telescopic rod and the second electric telescopic rod so that a relative distance between first adjusting rollers is adjusted and an elastic degree during a wire dividing process can be changed; and operation is simple and a user can conveniently use the device.

The invention discloses a monitoring camera fixing seat for firefighting. The monitoring camera fixing seat comprises a firefighting helmet, a dust removal structure, a camera body, a protective shell, cleaning sponge, a supporting rod, a threaded ring, a rotating block, a clamping block, a first spring, a guide rod, a mounting structure and an adjusting structure. The monitoring camera fixing seat has the beneficial effects that the lens of the camera body is protected through the transparent protective shell fixed at one end of the lens of the camera body, and in order to prevent dust from being attached to the camera body to influence the shooting work of the camera body, a threaded ring is in threaded connection with the outer side of the rotating block by rotating the rotating block rotationally connected with the protective shell; a supporting rod rotationally connected to the threaded ring is rotated by rotating a rotating block, cleaning sponge is fixed to the outer portion ofthe supporting rod and abuts against the protective shell, the supporting rod drives the cleaning sponge to rotate to wipe and clean the surface of the protective shell, the threaded ring is rotated to slide on a rotating block, and the abutting tightness degree of the cleaning sponge and the protective shell is changed.

The invention relates to the technical field of food purification, and discloses an easy-to-clean food purification water tank, which includes a water tank, a disinfection lamp is fixedly installed on the inner wall of the back of the water tank, and a vegetable dish composed of two left and right corresponding rectangular plates is inserted into the inner wall of the water tank The bottom of the vegetable storage column is fixedly connected with a filter screen, and the bottom of the inner wall on the left and right sides of the vegetable storage column is fixedly connected with several connecting plates at equal intervals. There is a water injection port on the right side of the water injection cylinder, and the inner wall of the water injection cylinder is inserted with an insert plate. Through the setting of the vegetable storage column, the vegetable storage column is cleaned by injecting water, and the power of the clean water injection is used to drive the vegetable storage column. The reciprocating shaking makes the bottom surface of the vegetable tray and the cleaning rod scrape each other, so as to achieve the function of automatically cleaning the vegetable tray carrying fruits and vegetables. Compared with manual cleaning, the cleaning range is guaranteed, and it has high cleaning efficiency and effect. benefit.

The invention discloses a flexible seal coal powder injection ball valve. The ball valve comprises a valve body, a valve cover and a sphere, and further comprises an insert, a sealing ring supportingring, an air bag, an air valve and a sealing ring. The insert comprises a concave torus, and the concave torus is of the step structure and integrated with a step-shaped structure. One end of the step-shaped structure is in contact with the valve body. The concave torus is in contact with the inner side surface of the valve cover. The sealing ring supporting ring is a circular annular half-ring surface, the outer sphere surface of the sealing ring supporting ring is in contact with the insert and the valve cover in a sliding mode, the head of the sealing ring supporting ring is loaded with thesealing ring, and the side surface of the sealing ring supporting ring is loaded with an O-shaped sealing ring. The sealing ring is opposite to the sphere. The air bag is a ring type sealing body made of rubber, the air bag is loaded with the air valve, and the air bag is loaded between the valve cover and the sealing ring supporting ring. The valve cover and the valve body are connected to forma valve inlet and outlet end face. The valve body is provided with a structure for removing dust accumulation in a valve body cavity, and the structure is through holes arranged on the left and rightbodies of the valve body. The flexible seal coal powder injection ball valve has the advantages of simple structure, reliable operation and long service life.

The invention discloses a tensioning wheel capable of changing the elastic degree of a belt at an original position. The tensioning wheel comprises a drive wheel body, a driven wheel body, a tensioning wheel body and the belt. The left and right ends of the belt are sleeved with a corresponding belt mounting groove in the driven wheel body and a corresponding belt mounting groove in the drive wheel body respectively. According to the tensioning wheel, the tensioning wheel body movably sleeves a rotation rod and is limited on the rotation rod through limit circular plates of the two sides, thetensioning wheel body and the rotation rod can keep relative rotation, and it is guaranteed that when the belt passes through the tensioning wheel body, the tensioning wheel body can rotate, and the belt smoothly passes through the tensioning wheel body; since the tensioning wheel body is of a circular-truncated-cone-shaped structure, when the tensioning wheel body moves front and back, the aim ofadjusting the elastic degree of the belt is achieved, the elastic degree of the tensioning wheel body can be changed at the original position, the tensioning wheel is conveniently adjusted and stablyfixed, and the situation is avoided that when the elastic degree is adjusted, the position of the tensioning wheel is freely moved, and accordingly the tensioning wheel is inconveniently fixed, or the space is wasted.