3672 results about "Crank" patented technology

A powered ratchet tool includes a housing and a motor disposed within the housing. The motor has an output shaft rotatable about a first axis. The powered ratchet tool further includes a ratchet mechanism supported by the housing and operably coupled to the output shaft to be driven by the motor. The ratchet mechanism has a crankshaft assembly defining a variable crank radius configured to change an extent of each rotational stroke of the ratchet mechanism. Moreover, the powered ratchet tool includes an output drive operably coupled to the ratchet mechanism to be rotated about a second axis perpendicular to the first axis.

The utility model relates to the technical field of electrical switches, in particular to an opening and closing device of a pole-mounted switch, which comprises a shell, a sliding rod, a crankshaft and a connecting rod. The linkage control device further comprises a driving mechanism, and the driving mechanism can drive the crankshaft to swing in a limited mode so as to drive the sliding rod to be switched between the upper limit position and the lower limit position, so that the pole columns are switched between the closed state and the separated state, and the linkage control device has the advantages that linkage control over the multiple pole columns is achieved through a mechanical structure based on the crank connecting rod principle; and the reliability and the convenience of opening and closing control of the pole are greatly improved. Due to the fact that linkage control is achieved, it can be guaranteed that the pole columns can be switched to the needed working state at the same time, and the use reliability and the on-off accuracy of the pole column module are greatly improved.

The utility model discloses a punching machine for power distribution cabinet production, which comprises a workbench, one side of the workbench is provided with a lubricating mechanism, the lubricating mechanism comprises a material box, the bottom of the left side of the material box is provided with a fixing pipe, one side of the fixing pipe is communicated with a frame body, one side of the frame body is movably connected with a crank shaft, and the crank shaft is movably connected with the workbench. The right side of the bottom of the workbench is fixedly connected with a double-shaft motor. According to the punching machine for production of the power distribution cabinet, the lubricating mechanism is arranged, an electric telescopic rod drives an adjusting plate to move, the adjusting plate drives a spray head to move, so that the spray head moves to the position between an upper die and a lower die, a double-shaft motor drives a crankshaft to rotate, the crankshaft drives an adjusting rod to move, the adjusting rod drives a fixing rod to move, and the fixing rod drives a sealing plate to move; when the sealing plate moves towards the inner side, the lubricating liquid can be pumped out through a fixing pipe, and when the sealing plate moves towards the outer side, the lubricating liquid can be discharged into a discharging pipe and then sprayed out through a spray head, so that the lubricating liquid makes contact with the upper mold and the lower mold.

The invention discloses multi-station welding equipment for automobile part machining and a method of the multi-station welding equipment, and relates to the field of automobile part machining. The multi-station welding equipment comprises a supporting table and a welding table rotationally installed at the top of the supporting table, a plurality of clamps are installed at the top of the welding table, a control cabinet is installed on one side of the supporting table, and a welding machine is installed on one side of the control cabinet; two transfer assemblies are installed on one side of the top of the supporting table. The driving block is driven by the crank to slide in the groove of the rotating plate, so that rotating motion is converted into intermittent indexing rotation of the rotating plate, the welding table is finally driven to rotate, the indexing precision is determined by the number of the driving grooves and strictly corresponds to a clamp station, it is ensured that each part can be accurately stopped below the welding machine, and the welding efficiency is improved. In order to guarantee the stability during machining, after the welding table rotates and is positioned, the locking mechanism can be immediately started to firmly fix the welding table, displacement in key welding and drilling procedures is effectively prevented, and therefore the accuracy and consistency of final machining are guaranteed.

The invention discloses a body position fixing device for radiology department examination, which comprises a bed body, a limiting mechanism, an unlocking mechanism and a plurality of fixing units, the limiting mechanism, the unlocking mechanism and the plurality of fixing units are arranged on the bed body, and the limiting mechanism and the unlocking mechanism are matched with the fixing units. Each fixing unit comprises a clamping plate, a first connecting rod, a second connecting rod, a crank, a movable block, a cylinder and a base, a movable groove is formed in the base, the cylinder is arranged in the movable groove and connected with the movable block, the second connecting rods are symmetrically arranged on the two sides of the movable block, the crank and the movable block are rotationally connected with the second connecting rods, and the crank is rotationally connected with the clamping plate; the clamping plate and the base are both rotationally connected with the first connecting rod. Through the application of the body position fixing device for examination in the radiology department, the operation process is simplified, the operation burden of medical staff is relieved, and the working efficiency of the medical staff is improved.

The application discloses a raw material sampling device for photoresist production and relates to the photoresist production field.The raw material sampling device comprises a bottom plate and a storage box fixedly installed on one side of the top of the bottom plate.In the sampling process, the driving motor drives the first crank through the belt transmission member, the first push rod is prompted to perform the circular motion, and then the first driving block is driven to slide, the mechanism ensures the swing of the swing rod, thereby causing the reverse force of the second driving block, the second crank is also moved, the rotating rod transmits the force to the sliding block, and the swing of the movable rod is caused, the movement directly controls the movement of the second fixed rod and the sampling member, the sampling tube can be accurately cut into the inside of the sample storage box, stable and consistent sampling is realized, sampling is carried out under the same standard and condition each time, the consistency of the sampling amount is ensured, the reliability of data is improved, and in addition, the automatic sampling process in the closed environment maximally reduces the external pollution risk.

The application discloses a kind of automobile seat slide rail structures, it is related to the technical field of automobile accessories, it includes outer rail, inner rail, rocker mechanism and guiding limiting mechanism;Rocker mechanism includes the rod body being arranged in inner rail, the proximal end of rod body is connected with crank after extending out of inner rail, the distal end of rod body is provided with locking plate and torsion spring;The side of locking plate is connected with rod body, the other side of locking plate is provided with several clamping teeth;The side wall of outer rail is provided with locking hole compatible with clamping tooth;Guiding limiting mechanism includes fixed plate, limiting pin and limiting block;Fixed plate is arranged in inner rail and below rod body, the middle part of fixed plate is provided with guiding slot along the axial direction of inner rail;The lower end of limiting pin is connected with the inner bottom wall of outer rail, the upper end of limiting pin is passed through guiding slot and then abuts on rod body;Limiting block is provided with through hole for rod body to pass through, and the upper end of limiting block is connected with inner rail, the lower end of limiting block is connected with fixed plate;Limiting pin and limiting block are made of rubber material.

The utility model relates to the field of agricultural machinery, in particular to a residual film picking and recycling straw beating machine, which comprises a main frame, a traction frame and traveling wheels, and a straw beating device, a residual film picking roller, a packing device and a transmission device are arranged on the main frame. The plastic film residue picking roller is characterized by structurally comprising a track disc device, a roller body, a center transmission rotating shaft, a shaft disc, a roller side plate, a film picking elastic tooth set, a film picking crank and a crank roller. The machine is reasonable in structure, economical and practical, and can realize the combined operation of picking, recycling and packaging the residual films and smashing and returning the straws to the field; in the picking process, the residual film picking roller can be utilized, the burden is small, the overall flexibility of the picking roller can be effectively improved, and the residual film picking operation efficiency is greatly improved; the special suspension traction frame is utilized to solve the actual problem that an included angle formed between power input and a transmission shaft is too small, and backward transmission of the locomotive is not facilitated, and flexible connection steering and transmission between the traction locomotive and the operation agricultural machine can be achieved.

A symmetrical link servo driving device, relating to the technical field of servo motors. The symmetrical link servo driving device comprises a driving mechanism, an electric motor, a gear reduction mechanism and a servo shaft rocker arm mechanism, wherein the gear reduction mechanism is in transmission connection with an output shaft of the electric motor, a servo shaft rocker arm mechanism is provided on the side of the gear reduction mechanism facing away from the electric motor, the servo shaft rocker arm mechanism comprises a base body, a servo shaft is rotationally connected to an inner cavity of the base body, and a crank is provided at a shaft body of the servo shaft; a self-locking mechanism capable of locking the servo shaft is provided at the bottom of the inner cavity of the base body; and a driving mechanism is provided on one side of the electric motor, the driving mechanism comprises a housing, a lead screw is rotationally connected in the housing, and the lead screw is correspondingly in transmission connection with an output gear of the gear reduction mechanism. The present invention has a simple structure, and the electric motor and the driving mechanism are arranged in parallel to effectively reduce the overall volume, such that the whole device is compact and small. The self-locking mechanism capable of locking the servo shaft is provided at the bottom of the inner cavity of the base body, that is, when the servo shaft stops rotating, the servo shaft can be locked by means of the self-locking mechanism, thereby preventing an external force from being transmitted to the driving mechanism by means of the servo shaft.

The invention discloses a multi-degree-of-freedom clamping mechanism of an industrial robot. The multi-degree-of-freedom clamping mechanism comprises a control base, a shaft base set and a clamping assembly. A first driving motor and a second driving motor are mounted on the bottom surface of the control seat; the shaft seat group is rotationally mounted on the inner side of the control seat and consists of a ring seat, a first transmission gear, a second transmission gear, a roll shaft and a shaft rod, the first transmission gear is meshed with the first driving motor to realize integral deflection, and the second transmission gear is meshed with the roll shaft through a bevel gear to realize rotary transmission; the clamping assembly comprises a swing seat, a clamping seat and a clamping lug, and a crank gear is driven by a shaft rod and a worm to drive the clamping lug to be opened and closed. And a touch switch is arranged on the guide cover and is matched with the servo control module to realize limiting protection and automatic resetting. The multi-posture clamping mechanism is compact in structure, high in degree of freedom and stable in transmission, multi-posture clamping and intelligent safety control of workpieces can be achieved, and the operation flexibility and safety of the industrial robot are remarkably improved.

The utility model discloses a safety hand-cranking mechanism for a point switch, which relates to the technical field of railway turnout switching equipment and comprises a fixing sleeve, a first bevel gear and a second bevel gear, two holes are arranged on the fixing sleeve, and the axes of the two holes are intersected; the end of the hand-cranking projecting shaft is located in one hole of the fixing sleeve, and the first bevel gear is arranged at the end of the hand-cranking projecting shaft; the other hole of the fixing sleeve is used for inserting the hand crank, and the second bevel gear is arranged at the end of the hand crank; the hand crank is inserted into the other hole of the fixing sleeve, so that the first bevel gear is meshed with the second bevel gear, and the switch machine is driven by rotating the hand crank; an identification ring is mounted in a hole, into which the hand crank is inserted, in the fixing sleeve; and an identification column is arranged on the hand crank in series with the second bevel gear. The included angle between the hand-cranking handle and the hand-cranking projecting shaft can be designed as required, so that the selection flexibility of the insertion position of the hand-cranking handle is greatly enhanced. Corresponding identification of the point switch and the hand crank is achieved, and safety is improved.

An aircraft wing includes a fixed structure and a linear hydraulic slat actuator attached to the fixed structure. The linear hydraulic slat actuator is oriented spanwise along the aircraft wing. The aircraft wing also includes an actuator output link and a slat attached to the actuator output link. The aircraft wing also includes a bell-crank coupled to the linear hydraulic slat actuator and to the actuator output link. In response to spanwise movement of the linear hydraulic slat actuator, the bell-crank is configured to move the actuator output link in a different direction that enables the slat to move between a retracted position and an extended position.

The invention belongs to the technical field of defect detection, and particularly relates to a forging part surface defect detection device which comprises a base, a controller is connected to the side wall of the base, a moving assembly is arranged in the base, and crankshafts are clamped by the moving end of the moving assembly and the surface of the base through clamping assemblies. The upper side wall of the base is fixedly connected with a mounting frame. When the surface defects of the crankshaft are detected, the surfaces of a journal, a crank arm and a balance block are synchronously detected in different areas, the device is adaptive to crankshafts of different models, detection blind areas caused by a complex structure can be greatly eliminated, and it is ensured that the defects such as microcracks and scratches of all key parts are not missed; meanwhile, the detection efficiency can be remarkably improved, and time loss caused by single-region successive detection is avoided; and the debugging period of tool clamps and parameters during detection of crankshafts of different models can be shortened, the equipment investment and the production cost are reduced, and the universality and the flexibility of the detection system are enhanced.

The invention discloses a pipe welder online inner crator and burr removing equipment device, and relates to the technical field of steel pipe welding, the pipe welder online inner crator and burr removing equipment device comprises a fixing frame, two sliding rails are symmetrically and fixedly mounted at the top of the fixing frame, a plurality of mounting frames and moving frames are slidably mounted at the tops of the two sliding rails respectively, and the mounting frames and the sliding rails are fixed through bolts; and a feeding mechanism, a delivery mechanism and a conveying mechanism are arranged on one side of each of the multiple mounting frames and the movable frame. A second air cylinder, a lead screw and a crank of the high-pressure inner burr blowing mechanism can adjust the position of an air nozzle body, adapt to steel pipes of different specifications and cooperate with a first air cylinder and a lower pressing plate to achieve stable positioning, and inner burrs are efficiently removed; a fourth motor, a sixth gear and a rack of the driving mechanism drive a moving frame to slide along a sliding rail to flexibly adapt to steel pipes with different lengths; a first gear, a second gear and a third gear of the delivery mechanism are linked to drive a first clamping piece on a moving plate to synchronously transfer multiple sets of steel pipes, and it is guaranteed that the rhythms of all procedures are matched.

The utility model discloses a film covering, fixed-point film breaking and soil covering all-in-one machine, which comprises a moving unit, a film covering unit and a soil covering unit, and is characterized in that the moving unit comprises a frame, a first gasoline engine arranged on the frame, walking wheels arranged on the frame, and a transmission part provided with a first transmission wheel; the film breaking unit comprises a second transmission wheel rotatably mounted on the frame, a crank rocker arm mechanism connected with the second transmission wheel, a film breaking rod mounted on the crank rocker arm mechanism and a drill bit mechanism mounted on the film breaking rod, and a transmission chain is mounted between the second transmission wheel and the first transmission wheel; the film mulching unit comprises a film cylinder frame, a film pressing wheel and a soil guiding wheel which are sequentially installed below the frame and in front of the drill bit mechanism from front to back, and the film pressing wheel and the soil guiding wheel are located on the two sides of the frame respectively; according to the equipment, two links of film mulching and fixed-point soil covering are seamlessly integrated, the soil filling and hole sealing operation procedure is moved forwards, the problem that labor is difficult to use in the links is effectively solved, and meanwhile convenience is provided for subsequent transplanting operation.

The application belongs to the technical field of crankshaft turning, in particular to a crankshaft machining and turning device, which comprises a lathe base, a fixing base is fixed to the top end of the lathe base, a sliding base is slidably connected to one side of the lathe base away from the fixing base through a No.1 electric sliding block, two V-shaped clamping blocks are arranged to clamp the outer wall of the crankshaft during turning, two conical rods are arranged to clamp the two ends of the crankshaft, the two V-shaped clamping blocks can clamp crankshafts of different thicknesses for turning, after the two ends of the crankshaft raw material are clamped by the two conical rods, four clamping plates are arranged at the crank wall on both sides of the turning position to clamp, which replaces the traditional clamping mode of the two ends of the crankshaft, can self-adaptively adjust the clamping position to clamp both sides of the turning position, improves the stability of clamping the eccentric crankshaft, reduces the situation of falling off of the crankshaft, improves the machining quality and the safety of the equipment, and reduces the failure rate and maintenance cost in the production process.

The invention relates to the technical field of heat exchange reaction kettles, in particular to a reaction kettle convenient to clean and a using method thereof.A kettle body rotates, a stirring shaft is static, and a centering eccentric disc slowly cuts an eccentric rotating shaft from a coaxial state to an eccentric state and approaches a kettle wall in an arc shape through the rotation difference of a friction wheel, a worm and a worm gear; the interactive pipeline is axially pushed and pulled to switch on and off, and synchronously drives the blade shell to flatten and stir or fold to scrape the wall through the connecting column, the movable sliding seat and the shifting column; the self-adaptive double cranks stretch and retract along with the eccentric distance, the kettle body is continuously rotated and conveyed to the two reverse thread conveying shafts at a constant speed, an upper-inlet lower-outlet independent channel is formed, fresh cleaning liquid goes deep from the gradually-expanded interaction groove, waste liquid is synchronously pumped back, and short-circuit-free circulating cleaning is achieved. Progressive scraping soft start is achieved, impact is small, the service life of the kettle wall and the service life of the scraper are remarkably prolonged, cleaning is efficient and water-saving, the structure is all integrated in the shaft, and switching of stirring, wall scraping and cleaning is completed without external power.

The invention relates to a drive device (2) for a bicycle (1), comprising a pedal crank shaft (19), a first electric machine (18), a first partial transmission (6), a second electric machine (49), and a second partial transmission (7), wherein a first transmission element of the first partial transmission (6) is operatively connected to the first electric machine (18), wherein a second transmission element of the first partial transmission (6) is operatively connected to a second transmission element of the second partial transmission (7), wherein a third transmission element of the first partial transmission (6) is operatively connected to an output gear (8), wherein a first transmission element of the second partial transmission (7) is operatively connected to the second electric machine (49), and wherein a third transmission element of the second partial transmission (7) is fixed to a housing (3), and wherein a freewheel (14) is arranged between the pedal crank shaft (19) and the second transmission element of the first partial transmission (6).Furthermore, the invention relates to a bicycle (1) with such a drive device (2).

The invention provides a cleaning device with an adjustable screening behavior suitable for densely-planted corn, and belongs to the field of corn harvesting machinery. Comprising an upper screen box, a shaking plate, a centrifugal fan, a crank connecting rod mechanism and a lower screen box, the centrifugal fan is fixedly connected with a harvester, the shaking plate is arranged above the centrifugal fan, one end of the shaking plate corresponds to a discharging port of a threshing device, the other end of the shaking plate is provided with the upper screen box, and the lower screen box is arranged below the upper screen box. The ends, close to the centrifugal fan, of the upper screen box and the lower screen box are connected through crank connecting rod mechanisms, the crank connecting rod mechanisms are symmetrically arranged on the two sides of the upper screen box and the two sides of the lower screen box, and a structural unit of the vibrating screen with the adjustable screen penetrating behavior is composed of an upper-section screen plate, a middle-section screen plate, a lower-section screen plate and an inclination-angle-adjustable screen plate. The throwing force of the front end area of the vibrating screen on mixture particles and the vertical speed of air flow on the screen are increased, the separation effect of impurities and grains is promoted, the grain penetrating through the screen is improved, and the low-loss and high-cleanliness purposes of corn grain cleaning are achieved.

The application discloses a circuit breaker and isolating switch linkage device for pole-mounted circuit breaker, wherein a main shaft rotates, and an insulating pull rod assembly is driven to move through a main shaft crank; a shift fork block in the insulating pull rod assembly pushes an isolating pin shaft in an isolating transmission assembly to move, and an isolating switch contact is driven to move through an isolating connecting rod and an isolating clamp; when an isolating limiting crank arm contacts a support, the isolating switch is closed to a position, the shift fork block is disengaged from the isolating pin shaft, and the isolating transmission assembly is no longer pushed. Through the connection relationship among the main shaft assembly, the insulating pull rod assembly, the isolating transmission assembly and a circuit breaker transmission assembly, the linkage of the circuit breaker and the isolating switch and the required action time interval of normal operation are realized, and the influence of the electric force of the isolating switch contact on the action of the circuit breaker is avoided. The application has the advantages of simple structure, small size, small number of components, high reliability and long service life.

The invention belongs to the technical field of kidney puncture, and particularly relates to kidney puncture equipment for living body examination, which comprises a crank assembly, a connecting rod assembly, a variable precision driving assembly, a lifting puncture assembly, a sampling pump, a double-shaft platform and a sliding plate, the sliding plate is arranged on the double-shaft platform, and the crank assembly and the variable precision driving assembly are arranged on the sliding plate. The connecting rod assembly is arranged between the crank assembly and the variable-precision driving assembly, the lifting puncture assembly is arranged in the middle of the sliding plate, and the sampling pump is arranged on the lifting puncture assembly. Under the condition that the precision and the speed of the driving motor are not changed, at the initial stage of descending of the hollow pipe, the relatively high puncture speed is obtained in a precision sacrificing mode, and at the tail stage of descending of the hollow pipe, the relatively high position control precision is obtained in a speed sacrificing mode.

The invention relates to a vehicle seat support structure (1). A seat cushion frame element (2) is supported by a front link (4) and a rear link (10). The rear link (10) is pivotally linked by a second rear link joint (11) to a vehicle seat base (8). The front link (4) is pivotally linked by a second front link joint (5) to a crank (6). The crank (6) is pivotally linked by a crank joint (7) to the vehicle seat base (8). A first actuator (18) is linked to the crank (6). An actuation of the first actuator (18) is in particular used for adjusting a tilt angle of the seat cushion frame element (2). A second actuator (19) is linked to the rear link (10). An actuation of the second actuator (19) is in particular used for adjusting the height of the seat cushion frame element (2).

The invention discloses an automatic detection and control method for a pressing roller in an SSP area. The automatic detection and control method comprises the following steps that S1, strip steel enters a waiting position; s2, whether the strip steel enters a pressing roller or not is judged, if yes, the step S3 is executed, and if not, the step S1 is executed again; s3, whether the main crank is at a set angle or not is judged, if yes, the step S4 is executed, and if not, the main crank is located at a second load position; s4, the main crank is located at a first load position; s5, whether the pressure of the pressing roller is larger than a set threshold value or not is judged, if yes, the step S6 is executed, and if not, the step S4 is executed again; s6, the pressing roller executes pressure control; and S7, whether the strip steel leaves the pressing roller or not is judged, if yes, the step S1 is executed, and if not, the step S6 is executed. It is guaranteed that the pressing roller of the strip steel does not slip, impact can be greatly reduced, roller face abrasion of the pressing roller is reduced, and the service life of the pressing roller is prolonged.

The application provides a cast power end frame including a pair of end plates and an outer casing extending between the end plates and defining an interior therein; a crank shaft housing extending between the end plates and within the interior of the outer casing, and a plurality of crosshead tubes, each crosshead tube extending substantially perpendicular to the crank shaft housing, wherein the outer casing, crank shaft housing, and crosshead tubes are cast as a single part comprising steel comprising a carbon constituent of 0.06%-1.99% carbon.

A bicycle includes a suspension system of the rear wheel, where the crankset and the hub and sprocket each include at least one chainring engaged by the chain and a rotation shaft. A compensation device is interposed between the toothed plate and the shaft to allow an angular compensation stroke between them from a rest position corresponding to the absence of the pulling of the chain, to a compensation position, corresponding to a pulling action of the chain generated by the rear suspension. The compensation device includes a plurality of pairs of brake elements and respective compensation end elements where at least one shock-absorbing element is operationally interposed between at least one pair capable of deforming only in correspondence with a final portion of the compensations stroke and between at least another pair where at least one limiting element is interposed to limit the maximum deformation of the shock-absorbing element.

The utility model relates to a belt slip detection protection device which comprises a speed measuring mechanism and a controller, the speed measuring mechanism comprises a fixed support, the fixed support is arranged on the inner side of a belt of a belt conveyor, a crank arm is installed on the fixed support, one end of the crank arm is rotatably connected with the fixed support, and the other end of the crank arm faces the surface of the belt and is provided with a synchronous wheel. The synchronous wheel is rotatably connected with the crank arm, a tension spring is further installed between the fixing support and the crank arm and used for pressing the synchronous wheel on the surface of a belt, a plurality of sensing parts are evenly distributed on the synchronous wheel along the circumference, a supporting rod is installed on one side of the crank arm, a photoelectric sensor is installed on the supporting rod, and the photoelectric sensor corresponds to the circumferential line position where the sensing parts are located. The photoelectric sensor is used for detecting the rotating speed of the synchronous wheel and is in signal connection with the controller, and the controller is in signal connection with a main control system of the belt conveyor; according to the utility model, whether the belt slips or not is effectively detected, and the conditions of heavy slipping and light slipping can be distinguished.

The invention belongs to the technical field of high-voltage electrics, and particularly discloses a transmission structure of a high-speed circuit breaker and the high-speed circuit breaker. A transmission mechanism is arranged between an operating mechanism and a moving contact, a transmission rod, a crank arm and a pull rod are matched to convert force of the operating mechanism in the vertical direction into force of the pull rod in the vertical direction, the operating mechanism drives the moving contact and a static contact to make contact or break through the transmission mechanism, closing or opening of the circuit breaker is achieved, and the transmission rod is in sliding connection with the crank arm. Force of the operating mechanism in the up-down direction is transmitted to the crank arm through the transmission rod, the crank arm rotates clockwise or anticlockwise to drive the pull rod to slide in the up-line direction, then the moving contact and the static contact are driven to be in contact or disconnected, linear motion of the operating mechanism and rotation of the crank arm do not interfere with each other and are not blocked, and the operating efficiency is improved. The high-speed circuit breaker solves the problem that the high-speed circuit breaker is prone to clamping stagnation during switching on or switching off, the high-speed performance of the circuit breaker is guaranteed, and the reliability of the high-speed circuit breaker and the safety of a system during operation are improved.

The utility model provides an elliptical machine with an adjustable step pitch. The elliptical machine comprises a machine frame, a flywheel assembly fixedly arranged on the machine frame and two swing assemblies symmetrically arranged on the two sides of the machine frame. The swing assembly comprises a swing arm rod rotationally connected to the machine frame and a pedal rod hinged to the swing arm rod, a crank is connected to a driving wheel rotating shaft of the flywheel assembly, the free end of the crank is connected with an extension rod used for prolonging the length of the crank, and a plurality of installation holes evenly distributed in the length direction of the extension rod at intervals are formed in the extension rod. And the free end of the foot rest lever is rotatably connected to one of the mounting holes. The step pitch of the elliptical machine is adjusted by adjusting the free end of the foot rest lever to be connected to different mounting holes, so that the elliptical machine is suitable for users with different step pitches, and the use experience of the users is improved.

A portable fence reel has a reel spool, and a frame including at least one arm, where the reel spool is rotatably mounted to the at least one arm. The fence reel also has a crank shaft, where rotation of a crank shaft results in rotation of the reel spool, and a winding handle. An automatic engaging mechanism includes a coupler rotationally fixed to the crank shaft, and a clutch portion configured to be driven by the winding handle and, in use, move along a longitudinal axis of the crank shaft to engage or disengage with the coupler.

A glider seating unit with a selectively powered gliding motion is provided. The glider seating unit includes a base frame and a glide assembly movably connected to the base frame. The glide assembly is configured to glide in a forward direction and in a backward direction relative to the base frame. A glider drive mechanism is connected to the base frame and includes a motor, a drive shaft connected to the motor, a crankshaft releasably connected to the drive shaft at a joint, and a linkage connected between the crankshaft and the glide assembly. Operation of the motor in a first rotational direction connects the drive shaft to the crankshaft to rotate the crankshaft to thereby induce reciprocating forward and backward gliding motion of the glide assembly relative to the base frame. Operation of the motor of the glider drive mechanism in an opposite, second rotational direction disconnects the drive shaft from the crankshaft to permit the glide assembly to glide freely forward and backward relative to the base.