6888 results about "Wheel drive" patented technology

The invention discloses a chassis coordination control method and system based on tire side deviation state evaluation, and relates to the technical field of four-wheel steering four-wheel drive vehicle dynamics control. The method comprises the steps that an expected front wheel rotation angle is determined based on an expected steering wheel rotation angle input by a driver, and a front wheel rotation angle is determined; further determining a feed-forward front wheel steering angle, a feed-forward rear wheel steering angle and an additional yaw moment based on feed-forward control and feedback control, determining a first tire slip angle and a second tire slip angle based on a road adhesion coefficient, and further determining a wheel torque control weight, a feedback front wheel steering angle control weight and a feedback rear wheel steering angle control weight; and further determining a driving yaw moment, a feedback front wheel steering angle and a feedback rear wheel steering angle, determining a total longitudinal force based on an expected longitudinal acceleration input by a driver, and performing four-wheel torque distribution based on the total longitudinal force and the driving yaw moment to obtain a four-wheel driving torque. The driving stability of the vehicle under the limiting working condition can be improved.

The invention discloses an intelligent automobile cooperative cruise safety control method under Dos attacks and physical faults, and relates to automobile intelligent safety and automatic driving. A hierarchical control framework is adopted and comprises an observer layer and a tracking layer. The method comprises the following steps: establishing a vehicle longitudinal dynamics model and a DoS attack model for DoS attack in a V2X communication network and the problems of sensor and actuator faults and parameter isomerism of a vehicle; a completely distributed self-adaptive preset time observer based on event triggering is designed for each following vehicle in the observer layer, and rapid and accurate estimation of the state of the pilot vehicle is achieved; the method comprises the following steps: constructing an augmentation system at a tracking layer, designing a distributed intermediate observer, carrying out online estimation and compensation on faults of a sensor and an actuator, designing a distributed active fault-tolerant controller based on a fault estimation value and a pilot vehicle state estimation value, and calculating a wheel driving torque to realize safe cruise control. Multiple threats of coexistence of network attacks and physical faults are effectively handled, and the stability and safety of the cooperative cruise system are ensured.

The invention discloses an air-ground multi-mode cross-domain robot system with a clutch structure and a control method. The air-ground multi-mode cross-domain robot system comprises a machine body, wings, clutch assemblies and rotor assemblies. The aircraft body drives the connecting rod mechanism through the steering engine to control the bilateral wings to move. Rotor driving motors, wheels and transmission gear sets are integrated on the wings, and motor power can be distributed to wheel driving shafts and propeller shafts. The clutch assembly is connected with a motor and a propeller shaft through a ratchet wheel meshing mechanism, and power on-off control is achieved, in the ground running process, a clutch is separated to stop rotation of a propeller, power is fully output to wheels to serve as driving wheels, and in the flight mode, the clutch is meshed to synchronously drive rotors and the wheels. According to the system, bimodal power distribution is achieved through a single motor, a driving wheel motor does not need to be additionally arranged, the structural complexity is effectively reduced, the moving speed and controllability are remarkably improved through the ground mode propeller static design, the advantage of cross-domain operation is achieved, and the system is suitable for complex task scenes.

Disclosed in the present invention is a flexible robot welding system for a middle rotary displacement pipe fitting. The flexible robot welding system comprises a clamp-type positioner and two welding systems located on two sides of the clamp-type positioner, wherein the clamp-type positioner comprises a driving wheel mechanism for driving pipe fitting to rotate and displace, and a clamp mechanism for pressing the pipe fitting; the clamp mechanism comprises a pressing wheel in contact with the pipe fitting, and a pressing-wheel driving device for driving the pressing wheel to ascend and descend, the pressing wheel rotating along with rotation of the pipe fitting and pressing the pipe fitting; the two welding systems are respectively located at two ends of the pipe fitting, and each welding system comprises a welding robot and an end pressing mechanism; and the end pressing mechanism comprises a pressing first roller in contact with the pipe fitting, and a roller driving device for driving the pressing first roller to ascend and descend, the pressing first roller rotating along with rotation of the pipe fitting and pressing the pipe fitting. The middle part and the two ends of the pipe fitting are pressed at the same time by means of the clamp-type positioner and the end pressing mechanism, such that straightness correction of the pipe fitting is achieved, thereby guaranteeing the welding quality.

The invention discloses a mahjong machine and a slope tile playing device thereof, which are characterized in that a planet carrier and a planet wheel which rotate actively rotate around a fixed sun wheel, and a tile feeding push rod is driven by the planet carrier, the planet wheel and a turntable to rotate to push and feed tiles; a mahjong lifting swing arm is driven by a planet carrier, a swing rod, a rack and a mahjong lifting gear to swing to drive a mahjong lifting supporting plate to lift mahjong; two transmission paths of a planet carrier and a planet wheel are ingeniously utilized, so that a mahjong feeding push head does not push mahjong tiles when a mahjong tile lifting supporting plate is controlled to descend only through mechanical transmission cooperation by a motor, and the mahjong tile lifting supporting plate does not move when the mahjong tile feeding push head pushes the mahjong tiles; when the tile lifting supporting plate is lifted, the tile feeding pushing head does not push tiles, after the tile lifting supporting plate is lifted, the tile feeding pushing head moves out of the tile storage groove, the lifting action of the tile lifting supporting plate and the tile pushing action of the tile feeding pushing head do not interfere with each other, the structure is simple and reasonable, action connection is good, operation is stable and reliable, the mahjong machine is coherent and smooth in action, noise is low, and the user experience is good.

The invention relates to the technical field of constructional engineering, and discloses bar planting integrated equipment and an operation method thereof.The bar planting integrated equipment comprises a bearing mechanism which comprises a machine shell, a storage groove formed in the outer side of the machine shell, telescopic supporting legs rotationally installed in an inner cavity of the storage groove and universal wheels fixedly installed at the bottom of the machine shell; the driving mechanism comprises a three-section type hydraulic telescopic column located in the center of an inner cavity of the machine shell, a ball bearing seat fixedly installed at the end of the three-section type hydraulic telescopic column and a jacking buffering assembly fixedly installed at the top of the ball bearing seat. And the integrated mechanism is used for integrated punching operation and comprises an operation support fixedly installed on the outer surface of the innermost section of the three-section type hydraulic telescopic column. An integrated platform is provided for the punching assembly, the hole cleaning assembly, the glue injection assembly and the steel bar planting assembly through the integrated mechanism, the assemblies can be reasonably distributed around operation points, operation of all steps is rapidly achieved, and therefore the operation efficiency is effectively improved.

The utility model relates to the technical field of cleaning equipment, in particular to a cleaning robot which comprises a robot body and an advancing assembly, the advancing assembly comprises a driving wheel, a supporting unit and an obstacle crossing wheel, the obstacle crossing wheel is arranged on the supporting unit, the supporting unit can rotate around the driving wheel, and the obstacle crossing wheel is arranged on the robot body. The driving wheels are arranged on the machine body so that the advancing assembly can be switched between an advancing state and an obstacle crossing state, and when the advancing assembly is in the advancing state, the driving wheels abut against the ground so as to drive the machine body to advance; when the advancing assembly is in the obstacle crossing state, the supporting units drive the obstacle crossing wheels to make contact with the ground, the driving wheels are made to break away from the ground, the obstacle crossing wheels drive the robot body to advance, and the obstacle crossing capacity of the cleaning robot is improved.

The invention relates to the technical field of furnace shell welding, in particular to a gas industrial furnace shell welding device which integrates a radial circular seam and an axial longitudinal seam, a servo motor drives a planetary gear train through an intermittent sheave, a rotating shell drives a clamped furnace shell to rotate, and radial welding is completed; after a bottom clamping jaw instantly locks a shell, power is switched to a planet carrier, an outer mounting arm drives a driven scraping arm to grind the inner wall while axially moving, welding and grinding synchronization is achieved, a bidirectional pushing seat crank sliding block mechanism continuously rotates in a one-way mode to push and pull the furnace shell in a two-way mode, whole-circle accurate grinding is achieved during resetting, and six sets of air cylinder lead screw adjustable clamping jaws conduct internal and external synchronous supporting. The outer supporting cylinder is prevented from deformation, secondary clamping is not needed in the whole process, butt joint of multiple sections of furnace shells is completed at a time, continuous filling of a longitudinal weld bead can be completed when a circular seam is still in a high-temperature plastic stage through instantaneous switching of clamping and stopping, and the welding quality of a T-shaped connector area is improved.

In one aspect, an in-wheel drive assembly is provided that includes a stator configured to form a non-rotatable connection with a spindle of a vehicle and be positioned outboard of the spindle. The in-wheel drive assembly includes a stator retainer configured to extend in an interior of the spindle and inhibit movement of the stator in an outboard direction relative to the spindle. The in-wheel drive assembly further includes a rotor rotatably supported by the stator, an output housing to be connected to a wheel hub, and a planetary gear assembly operatively connecting the rotor and the output housing. The planetary gear assembly is configured to cause rotation of the output housing and wheel hub connected thereto in response to rotation of the rotor.

The invention discloses an aircraft landing gear shimmy test bed and a test method, the aircraft landing gear shimmy test bed comprises a main body rack, a hanging basket system, a large flywheel, a flywheel driving system, an excitation device and a follow-up displacement measurement system.The aircraft landing gear shimmy test bed can simulate the shimmy of an aircraft after undercarriages of different design configurations are subjected to interference excitation force or interference torque in the process of takeoff, taxiing, landing and the like of the aircraft; the control effect of the shimmy damping system on the stability of the undercarriage has short excitation time so as to simulate real working conditions, the shimmy stability performance of the undercarriage can be accurately detected, excitation is continuously carried out under the condition that the test state is continuously changed, and the working efficiency is greatly improved. The follow-up displacement measuring system designed by the invention can enable the exciting force and the center of the axle to be always kept on the same horizontal plane, can apply torque control and torque excitation control, is suitable for undercarriage shimmy tests with different axle heights, different tire diameters and different excitation modes, and has certain universality.

The present invention relates to the technical field of cable surface repair, and particularly relates to a surface repair device for overhead insulated cables; it includes a support frame, a bidirectional motor, an arc-shaped plate, a transmission shaft, a transmission gear, a turnover assembly, a runner bracket, a rotating shaft, a moving wheel, a driving motor, a cleaning assembly, and a winding assembly; the present invention can solve the following problems existing in the prior art during the repair of the surface of overhead insulated cables: it is impossible to clean the dirt and loose materials at the damaged part of the insulated cable; only coating the outer wall of the insulated cable with a waterproof insulating paint cannot guarantee the repair quality; through the cooperation of the turnover assembly and the cleaning assembly, the present invention can clean the dirt and loose materials at the damaged part of insulated cables with different diameters; through the cooperation of the turnover assembly and the winding assembly, the present invention drives the insulating tape to wind around the outer wall of the insulated cable and simultaneously rolls the insulating tape, so that the bonding effect between the insulating tape and the insulated cable is better.

The invention discloses a mobile robot control method and system, and relates to the technical field of mobile robot intelligent motion control, and the method comprises the steps: collecting environment feature data and motion state data; performing preprocessing and feature fusion to generate standardized state data; constructing a reinforcement learning training environment in an offline simulation environment, and obtaining a convergent reinforcement learning strategy model; inputting the current robot standardized state data into the reinforcement learning strategy model, and obtaining and outputting a preliminary motion control instruction and a reference trajectory; a prediction control model MPC is established, current robot standardized state data are input, short-time motion prediction and optimization are carried out, and a final control instruction meeting constraint conditions is obtained through solving; instructions are distributed to the four Mecanum wheel drivers, and the rotating speed and the direction of each wheel are adjusted. According to the invention, high-precision trajectory tracking, adaptive obstacle avoidance and energy efficiency optimization of the mobile robot in a complex dynamic environment are realized, and the system stability and the intelligent level are improved.

The invention discloses a wheel-driven bearing cable type gravity flow energy storage system and an energy storage method, and relates to the technical field of gravity energy storage. The wheel-driven bearing cable type gravity flow energy storage system comprises a first steering wheel, a second steering wheel, a carrying device, an energy storage device, a driving device, a power generation device, a bearing cable and a traction cable, the energy storage device is detachably connected to the carrying device; the driving device drives the traction cable to operate in the first direction so as to convey the multiple energy storage devices to the high altitude position, and electric energy is converted into gravitational potential energy to be stored. A plurality of carrying devices loaded with energy storage devices walk along the bearing cable and are conveyed to a low altitude position successively to form a continuous gravity flow so as to drive the power generation device to discharge continuously. The energy storage method is suitable for the wheel-driven bearing cable type gravity flow energy storage system. The invention provides a wheel-driven bearing cable type gravity flow energy storage system and an energy storage method, and aims to solve the technical problem of discontinuous charging and discharging caused by intermittent load generated by lifting energy storage blocks one by one in the prior art.

The invention belongs to the technical field of mowing machines, and particularly discloses a wheel-foot combined type all-terrain mowing machine and an active obstacle crossing control method thereof.The mowing machine comprises a rack, a mowing device is installed on the rack, four bionic feet are installed on the rack, each bionic foot comprises a thigh part, the first end of each thigh part is hinged to the rack, and the second end of each thigh part is hinged to the rack; the second ends of the thighs are hinged to the shank parts, walking wheels are rotationally installed at the ends, away from the thighs, of the shank parts, thigh part driving devices are arranged between the rack and the thighs, shank part driving devices are arranged between the thighs and the shank parts, and walking wheel driving devices are installed on the shank parts. Through cooperative work of the bionic feet and the walking wheels, high-speed movement and complex terrain adaptability are both considered; dynamic adjustment of the mowing height can be achieved, the operation scene is expanded, and the mowing knife is protected against collision; according to the improved mower, manual intervention can be reduced, and the risk of equipment damage caused by complex terrain is reduced.

A coaxial asynchronous motor drive system, including a speed reducer, an electric motor and a main housing, and further including a motor controller, wherein the electric motor and the speed reducer are connected to form a motor reducer assembly and mounted inside the main housing, and the motor controller is fixed to the main housing and connected to the motor reducer assembly. The system reduces parasitic loss of an auxiliary motor drive system of a battery electric four-wheel-drive vehicle and increases the range per charge of the vehicle, and the compact and integrated coaxial motor drive system facilitates maximum utilization of available space of the vehicle.

In some aspects, a speed reducer includes an inner gear having an inner gear hole; an outer gear having an outer gear hole, arranged in the inner gear hole and meshing with the inner gear; an eccentric wheel rotatably supported in the outer gear hole, the outer gear being driven by the eccentric wheel to revolve around the rotation axis of the eccentric wheel while rotating around its own axis; a brake block arranged on the eccentric wheel to rotate together with the eccentric wheel, the brake block being movable relative to the eccentric wheel between a braking position and a release position; an elastic member coupled to the eccentric wheel and the brake block, and configured to press the brake block towards the braking position; and a drive member coupled to the eccentric wheel, a rotation axis of the drive member being coaxial with the rotation axis of the eccentric wheel.

The invention discloses an automobile part aluminum plating tool with overturning and clamping functions, and relates to the technical field of film plating tools, the automobile part aluminum plating tool comprises a driving assembly, a fixed outer frame and a plurality of overturning and clamping assemblies, and each overturning and clamping assembly comprises a deflection connecting rod, a telescopic rod, a workpiece chuck and a guide sleeve rod; when the driving assembly ascends and descends, the deflection connecting rod is driven by the first hinge shaft to deflect, the telescopic rod is forced to slide in the radial direction of the guide sleeve rod, and the workpiece chuck generates clamping / releasing displacement. An inner transmission ring is arranged on an inner ring of the fixed outer frame, a transmission wheel is installed at the lower end of the guide sleeve rod, and when the driving disc rotates, a planetary gear train enabling the overturning clamping assembly to rotate is formed through transmission of the inner transmission ring and the transmission wheel. A multi-drive structure is replaced with mechanical layout, modular layered layout improves efficiency, structural innovation guarantees stability, integration of self-adaptive clamping, composite motion and batch processing is achieved in the field of vacuum coating, and the bottleneck that a traditional tool is insufficient in flexibility and poor in uniformity is broken through.

The invention relates to the technical field of galvanized coiled plate machining, in particular to a galvanized coiled plate edge cutting device and an edge cutting method thereof.The galvanized coiled plate edge cutting device comprises an operation table, two rotating holes are formed in the upper side of the operation table, edge cutting and polishing assemblies are rotationally installed in the two rotating holes, and spraying assemblies are fixedly installed on the two sides of the operation table; an adjusting knob is manually rotated, the manual adjusting knob drives a worm to rotate, the worm drives a worm gear to rotate, the worm gear drives a first-stage half gear to rotate, the first-stage half gear drives a second-stage half gear to reversely rotate, the first-stage gear drives a driving block to move, and the driving block drives a driving plate to horizontally move under the limiting action of two sliding rails; the polishing support drives the polishing rollers to move, the two polishing rollers abut against each other correspondingly, after the cutter completes edge cutting, the two polishing motors are started, the output ends of the two polishing motors drive the polishing rollers to rotate at a high speed, and the cut edge area is polished to remove burrs.

The invention discloses a flexible exoskeleton execution device and a flexible exoskeleton system for upper limb training, and relates to the technical field of robots. The problems that an existing exoskeleton robot is complex in mechanical structure, large in size, heavy in weight and large in inertia due to the fact that rigid driving is adopted for achieving actions such as joint bending and stretching or unfolding and folding are solved. The device comprises a bandage, a forward line wheel, a reverse line wheel, a line wheel driving mechanism and Bowden lines, the bandage is fixed to a limb, one end of one Bowden line is wound around the forward line wheel, the other end of the Bowden line is fixed to the bandage, one end of the other Bowden line is reversely wound around the reverse line wheel, and the other end of the other Bowden line is fixed to the bandage; the line wheel driving mechanism is arranged on the trunk and can drive the forward line wheel and the reverse line wheel to rotate reversely in the pre-tightening stage so as to achieve line winding and pre-tightening, the forward line wheel and the reverse line wheel are driven to rotate synchronously in the same direction in the working stage, and correction force is applied to the force exerting muscle group through the two Bowden lines which are wound and unwound alternately so as to correct the action of a wearer.

The invention relates to an all-drive unmanned vehicle tracking control and torque control method based on a residual error model. The method comprises the following steps: establishing a nonlinear vehicle dynamics model and a Gaussian process-based residual error model; combining the two models to obtain a vehicle dynamics model based on the residual error model; establishing a Gaussian-model predictive control GP-MPC controller for path tracking by taking transverse compensation and course angle minimization as optimization targets and taking a vehicle dynamics model based on a residual model as a prediction model; a multi-target torque control algorithm is designed, the optimal control quantity output by the GP-MPC controller is distributed, and the expected longitudinal force of each tire is obtained; and designing a tire longitudinal force observer and an anti-interference current control law. According to the invention, the defects of poor tracking precision and poor stability of an all-drive unmanned vehicle are effectively overcome.

The present disclosures relate to methods and systems for a hybrid powertrain. The hybrid powertrain system includes an integrated axle configured to provide mechanical power to a first pair of wheels, the integrated axle comprising a first motor-generator and a first drive axle such that the first motor-generator and at least a portion of the first drive axle are mechanically coupled to a common housing. The system also includes a second motor-generator configured to be mechanically coupled with an engine via a first clutch and mechanically coupled with a second drive axle via a second clutch, the second drive axle mechanically coupled with a second pair of wheels. A controller is electrically coupled with the first and second motor-generators, the engine, and the first and second clutches, the controller configured to enable a fully electric mode, a series hybrid mode, a parallel hybrid mode, and a regenerative mode of operation.

The invention belongs to the field of vacuum pumps, and provides a vacuum pump and application thereof in refrigerators.The vacuum pump comprises a pump body, the pump body is composed of a bottom cover, a middle cover and an end cover, the middle cover is located between the bottom cover and the end cover, a motor is arranged on the side, away from the middle cover, of the bottom cover, and an output shaft of the motor extends to the inner side of the bottom cover to be connected with an eccentric wheel; the outer edge of the eccentric wheel is in contact with a leather cup support slidably connected with the bottom cover, and a guide hole is formed in the middle of the leather cup support. A leather cup and a steel needle linkage mechanism are adopted to replace an electromagnetic valve, a motor drives an eccentric wheel to drive a leather cup support to do reciprocating motion, a pull cup is pulled to do reciprocating deformation in the motion process, reciprocating air exhaust is conducted by changing the size of the space of a pump body cavity, working noise is effectively controlled, and meanwhile the air exhaust speed is increased; and compared with a traditional electromagnetic valve, the volume of the low-oxygen fresh-keeping electromagnetic valve is effectively reduced, and the space utilization rate in the working process is improved.

The invention relates to the technical field of wood strength detection, in particular to a strength testing device for a wood composite board and a detection method.The strength testing device comprises a base table and a driving base fixed to the base table, and is characterized by further comprising symmetrical supporting mechanisms; a driving mechanism is arranged in the driving base so as to drive the two sets of supporting frames to be close to or away from each other. A centering roller and first pressure sensor cooperation mechanism of the transverse centering mechanism is adopted, a roller driving mechanism is combined to drive a driving roller to rotate, a plate is driven to transversely move through friction force, two sets of first pressure sensors detect the pressure bearing value of the roller in real time, and rotation is stopped when the numerical values on the two sides are equal; the transverse center of the plate is aligned with the axis of the driving roller, and personal errors are eliminated.

The invention discloses a four-wheel drive lifting type agricultural universal chassis with an adjustable wheel tread. The four-wheel drive lifting type agricultural universal chassis comprises a frame and four groups of leg-wheel assemblies, the vehicle leg-wheel assembly comprises a vehicle leg assembly, the vehicle leg assembly comprises a vehicle leg support and a wheel assembly, and a lifting adjusting mechanism is arranged between the vehicle leg support and a wheel; the vehicle leg support is in running fit with the vehicle frame through a fixed shaft, wheel track adjusting driving mechanisms are arranged on the vehicle frame in one-to-one correspondence with the vehicle leg assemblies, and the wheel track adjusting driving mechanisms are used for adjusting the wheel track between the wheel assemblies; the lifting adjusting mechanism comprises an electric cylinder and a sliding square tube guide structure, the sliding square tube guide structure comprises an outer square tube fixedly connected to the vehicle leg support and an inner square tube capable of sliding in the outer square tube, one end of the electric cylinder is connected with the vehicle leg support, and the other end of the electric cylinder is connected with a welding plate integrally welded with the inner square tube; a steering execution mechanism is arranged in the inner square tube; the wheel assembly comprises a wheel support and wheels installed on the wheel support, and hub motors are integrated in the wheels to achieve four-wheel independent driving.

The invention discloses a control method, device and equipment of a hydrogen engine and a storage medium. The control method comprises the steps that the engine rotating speed and the engine torque are obtained; under the transient working condition of the engine, the operation area of the engine is determined according to the engine rotating speed and the engine torque; and controlling the driving motor, the mechanical transmission assembly or the exhaust gas turbine according to the operation area. According to the technical scheme, the engine rotating speed and the engine torque are obtained in real time, the operation area of the engine is judged, different supercharging modes are determined through the waste gas turbine, the driving motor and the mechanical transmission assembly according to the operation area of the hydrogen engine, the problem that the transient dynamic performance is poor is effectively solved, and the application range is wide. The transient dynamic performance of the hydrogen internal combustion engine is improved, and efficient cleaning application is achieved.

The utility model relates to the technical field of stainless steel plate polishing, and discloses a stainless steel plate surface polishing treatment device which comprises a main body structure and a cleaning structure, the cleaning structure is arranged at the bottom of the main body structure, the main body structure comprises a polishing box body, and a stainless steel plate to be polished is placed in the polishing box body. Two clamping plates are driven by an electric push rod to clamp a stainless steel plate, a telescopic air cylinder is started to drive a limiting plate to downwards limit and fix the stainless steel plate, displacement of the stainless steel plate in the polishing process is avoided, and polishing equipment is driven by a driving motor, a screw rod, a moving seat and an electric telescopic rod to polish the stainless steel plate. After the single face of the stainless steel plate is polished, the servo motor is started to drive the first rotating wheel to rotate, the rotating first rotating wheel drives the second rotating wheel to rotate through the crawler belt and drives the shaft rod and the rotating rod to rotate at the same time, and in this way, the stainless steel plate is turned over, and other surfaces are polished.

The utility model discloses an expansion joint width gauge for bridge detection, which belongs to the technical field of bridge detection and comprises a distance sensor, a distance measuring piece, a main body, a first rotating wheel, a second rotating wheel, a driving piece, a first connecting rod and a second connecting rod. The first connecting rod and the second connecting rod are symmetrically arranged on the two sides of the cavity, the middles of the first connecting rod and the second connecting rod are rotationally connected with the through groove, the first rotating wheel is rotationally connected to the end, away from the cavity, of the first connecting rod, the driving part is fixedly connected to the end, away from the cavity, of the second connecting rod, and the second rotating wheel is fixedly connected to the output end of the driving part. According to the bridge expansion joint width gauge, the problems that an existing width gauge cannot carry out whole-line detection on a bridge expansion joint, installation is extremely inconvenient, and then the bridge detection effect is affected are solved.

The invention relates to the technical field of valves, in particular to a high-pressure-resistant quick opening and closing flat valve which comprises a valve body, a first valve seat, a second valve seat, a valve plate and a valve rod. The first valve seat and the second valve seat are arranged in a medium channel of the valve body, the valve plate is arranged between the first valve seat and the second valve seat in a sealing and sliding mode, and the valve rod is in driving connection with the valve plate. The middle of the valve rod is slidably connected to a valve deck in the middle of the top of the valve body, the hand wheel driving mechanism is connected to the upper portion of the valve deck, a pressure relief pipeline is arranged on the valve body, and the two ends of the pressure relief pipeline are communicated with a high-pressure side cavity, back to the valve plate, of the first valve seat and a low-pressure side cavity, back to the valve plate, of the second valve seat respectively. The pressure relief pipeline is provided with a pressure relief control valve used for controlling connection and disconnection of the pressure relief pipeline. The pressure difference generated by high-pressure fluid on the two sides of the valve plate can be balanced before the valve plate is opened, the main factor causing huge operation torque is fundamentally eliminated, opening and closing of the valve plate are extremely labor-saving and rapid, and rapid opening and closing under the high-pressure working condition are achieved.

A riding lawn mower comprising, a pair of rear drive wheels, a pair of front wheels, a deck positioned between the pair of front wheels and the pair of rear drive wheels, a rotatable cutting blade, and multiple battery packs removably coupled to the riding lawn mower and structured to provide power to the riding lawn mower, each battery pack graspable and removable by a user, wherein the multiple battery packs sequentially provide power to the riding lawn mower.