101results about How to "Achieve the purpose of braking" patented technology

The invention relates to the technical field of petroleum drilling safety, in particular to a safe monitoring and protection device for drilling and an intelligent protection system of the safe monitoring and protection device. The safe monitoring and protection device for drilling comprises a data acquisition unit, a control processing unit and a safe protection execution unit; the control processing unit comprises an PLC (programmable logic controller) and an industrial personal computer, the PLC is connected with the industrial personal computer through a serial port; various kinds of sensors of the data acquisition unit acquire on-site operation data and transmit the data to the PLC and the industrial personal computer in real time; the safe protection execution unit comprises a pumping pressure protection mechanism and a runner wagon protection mechanism; a pressure sensor mounted on a vertical pipe or a slurry pump, a winch sensor mounted on a winch barrel and a weight transducer mounted on a deadline anchor output signals to be connected with the PLC; the PLC is in control connection with the pumping pressure protection mechanism and the runner wagon protection mechanism. According to the safe monitoring and intelligent protection device for drilling, the safe protection execution unit comprises a pumping pressure protection sub-system which mainly adopts an active response type safe protection method, and when pumping pressure reaches a set protection value, the pump stops firstly and then pressure relief is performed.

The invention relates to a power-losing trigger type steel wire rope brake and a braking method thereof. According to the structure of the steel wire rope brake, a rope channel is arranged in a frame; braking clamp blocks are arranged on the two sides of the rope channel respectively; friction plates are arranged on clamping faces of the two braking clamp blocks respectively; at least one of the two braking clamp blocks is a movable clamp block; tension springs are arranged on the frame, so that the back faces of the movable clamp blocks are attached to the inner edge of the frame; longitudinal sliding grooves are formed in the back faces of the clamping faces of the movable clamp blocks; power-losing trigger braking electromagnets are arranged on the frame and provided with braking push rods abutting against the interiors of the sliding grooves in the back faces of the movable clamp blocks; and E-shaped faces with the middles protruding are arranged on the back faces of the movable clamp blocks, and a conical face with the middle concaved is arranged on the inner edge of the frame. An elevator car or a weight can be immediately clamped by the steel wire rope brake during upward heading and downward sliding, and malignant consequences caused by accidents are avoided.

The embodiment of the invention provides an air braking system and a control method of the air braking system. The air braking system comprises a redundancy channel, a distribution valve and a braking vitrified clay pipe, wherein one end of the redundancy channel is connected with a main blast line and the other end of the redundancy channel is connected with the braking vitrified clay pipe; when a railway locomotive is emergently braked, the redundancy channel receives main blasts in the main blast line; when the air pressure of the main blasts received by the redundancy channel is higher than the air pressure of compressed air in the braking vitrified clay pipe for a preset threshold value, the redundancy channel conveys the received main blasts into the braking vitrified clay pipe, and the air pressure in the braking vitrified clay pipe is increased. The distribution valve is connected with a control vitrified clay pipe and used for inflating the braking vitrified clay pipe with the compressed air, so that the air pressure in the braking vitrified clay pipe is increased. When the value of the air pressure in the braking vitrified clay pipe is not smaller than a preset numerical value, the railway locomotive is braked.

This invention relates to one clamp disc brake, which comprises card clamp rack, card clamp part, friction bus, upper cover, pressure arm with other end fixed on the cover and rotation socket, wherein, the racket two sides have screw holes connected with screw bar with its down end through axis socket connected with pressure block; the block bottom and friction bus block surface are contacted together; the one screw bar has adjusting gap drive axis automatic structure; the other screw bar has adjusting gap passive axis structure bus connected through one simultaneous drive structure.

The invention discloses a speed retarder of a proportional valve control pump type medium and low power vehicle, comprising a hydraulic pump driving gear, a hydraulic pump and a proportional overflow valve; wherein an inlet of the hydraulic pump is connected with an oil tank; a rotor of the hydraulic pump is mechanically connected with a hydraulic pump driving gear shaft; and the proportional overflow valve 7 is electrically connected with an ECU and connected with an outlet of the hydraulic pump and a heat exchanger by a hydraulic pipeline. The speed retarder has the beneficial effects that 1. the heat generated by energy loss can be taken away by the hydraulic oil while the vehicle is auxiliarily braked by the speed retarder; 2. the speed retarder is easy to be controlled by a computer so as to provide a stable and accurate braking torque; 3. wear is basically not generated and the service life is long; and 4. power source is not needed and the structure is simple.

The invention relates to a rope gripper. According to the structure of the rope gripper, two braking and clamping blocks with opposite clamping faces are arranged in a frame. A rope channel is formed between the clamping faces of the two braking and clamping blocks. The clamping faces of the braking and clamping blocks are provided with friction plates. At least one of the braking and clamping blocks is a movable clamping block capable of moving in the frame up and down. Tension springs capable of pulling the movable clamping blocks so that the back faces of the movable clamping blocks can be attached to the inner edge of the frame are arranged between the movable clamping blocks and the frame. The back faces, opposite to the corresponding clamping faces, of the movable clamping blocks are inclined faces so that the movable clamping blocks can form wedge-shaped blocks. The inner edge, attached to the back faces of the movable clamping blocks, of the frame is an inclined face combined with the back faces of the movable clamping blocks. By the adoption of the rope gripper, a lift car or a hoisted heavy object can be clamped immediately by the rope gripper no matter in the upward hoisting process or the downward sliding process, and vicious consequences caused by accidents are prevented.

The invention discloses an intermediate shaft brake of a proportional valve control pump type automatic speed changer, comprising a hydraulic pump and a proportional overflow valve; wherein an inlet of the hydraulic pump is connected with an oil tank; and the proportional overflow valve is electrically connected with a TCU of the automatic speed changer and connected with an outlet of the hydraulic pump and the oil tank by a hydraulic pipeline. The intermediate shaft brake has the beneficial effects that 1. the heat generated by energy loss can be taken away by the hydraulic oil while the intermediate shaft of the automatic speed changer brakes so as to provide a stable and accurate braking torque; 2. wear is basically not generated, the service life is long and the maintenance cost is effectively reduced; and 3. power source is not needed and the structure is simple.

The invention relates to an electronic fetter, in particular to an electronic fetter for controlling the action of controlled personnel within small area range. The electronic fetter comprises a transmitter part and a receiver part, wherein the transmitter part consists of a wireless transmission module and an electric shock switch; and the receiver part consists of a metal fetter, a metal lock catch, a wireless receiving module, an audible alarm module and a high-voltage electric shock module. According to the electronic fetter, wireless data is transmitted outwards by a transmitter and is received by a receiver, so that distance between the transmitter and the receiver is calculated; and when the distance exceeds a preset value, the receiver part produces sound to alarm the controlled personnel, and supervisors can send instructions by the transmitter to perform electric shock on the controlled personnel, so that the aim of controlling the action of the controlled personnel is fulfilled.

The invention discloses a brake which belongs to a brake on an aluminum extrusion production line and particularly belongs to a brake adopting high pressure oil or compressed air as brake power for braking and a disk spring for returning, in order to solve the problem of inaccurate stop position of a tractor. The brake at least comprises a cylinder (1), a piston (2), a support plate (5), a support (6), a locking block (8) and a brake pad (9). When the brake is in work, hydraulic oil or compressed air enters the cylinder (1) through a hole (10) of the cylinder (1) and pushes the piston (2) to drive the brake pad (9) onto a braking surface, thereby implementing rapid braking. According to the brake, the tractor can rapidly, accurately and safely stop at a position required by a process; and the brake is high in automatic degree, reliable in braking, and convenient to operate.

The invention discloses a permanent magnet powerless magnetic brake which comprises a stator assembly and a rotor assembly, wherein the stator assembly comprises a coil assembly, an inner yoke, an outer yoke and a permanent magnet, one end of the inner yoke is fixedly connected with one magnetic pole end of the permanent magnet, the other magnetic pole end of the permanent magnet is fixedly connected with one end of the outer yoke, and the coil assembly is arranged in a gap between the inner yoke and the outer yoke; the rotor assembly comprises a flange, a face-shaped spring and an armature, and the flange is connected with the armature through the face-shaped spring; and the other end of the inner yoke and the other end of the outer yoke are in tight surface-to-surface contact with the armature. The permanent magnet powerless magnetic brake provided by the invention has the advantages that the permanent magnet generates magnetic force to absorb the armature, thus realizing braking; and the structure is stable, the service life is long, the processing is simple, and the cost is low.

The invention discloses a drum brake of an electric vehicle and a control method thereof. A brake shoe assembly and a cam are mounted on a brake bottom plate; then an electromagnetism actuator is connected with the cam through a connecting rod, wherein the electromagnetism actuator comprises a base, one end of the base is provided with a base mounting hole used for being fixedly mounted on a vehicle body, and the other end of the base is provided with an electromagnet left sucking disc; the base is connected with one end of an electromagnet right sucking disc through a connecting device; by adjusting the size of the current in electromagnetic coils of the left and right electromagnet sucking discs, under the effect of the connecting rod, the spring axial force is turned into the rotation couple moment of the cam; brake shoe pieces are driven by rotation of the cam to open, so that the purpose of braking is achieved; return springs are mounted between two brake shoes, so that the brake shoes are in a closed state when the brake does not work; and the electromagnetic induction principle is utilized to replace a pneumatic brake device, so that the braking performance of the electric vehicle is greatly improved, and the limitation of application of the electric vehicle is relieved.

This invention relates to braking system of all kinds of autos. The existing braking equipment as brake disc and brake drum all adopts friction theory, but this invention adopts electromagnetic induction theory. Moment on auto half way around axis is transferred to reluctance machine after accelerated by accelerator, then energy brought by auto inertia is transformed into electrical energy by reluctance machine, the electrical energy is then transformed into heat energy of stator and rotor and other resistance of electric machine, so velocity of energy transform is accelerated greatly, braking distance is shortened and auto safety is increased.

The invention discloses a brake, comprising a mechanical driving mechanism and a braking rack push-rod mechanism, wherein the mechanical driving mechanism comprises a drive motor, a first driving gear, a driving belt and a second driving gear; and the braking rack push-rod mechanism comprises a first sun wheel driven by the second driving gear, a speed-reduction incremental size mechanism connected with the first sun wheel, a first reducing gear extended out from the speed-reduction incremental size mechanism, a second reducing gear mutually engaged with the first reducing gear and a third reducing gear driven by the second reducing gear. The third reducing gear drives a rack acting on a brake block to move by engagement. The brake adopts the non-thread gears and a rack driving mechanism. When reaction force is larger than forward propulsion, a propulsion unit of the mechanism can realize automatic backtracking, so that brake output is regulated by controlling the size of brake output torque, the non-self-locking function is realized, and the response performance of power conditioning of the brake is improved.

The invention relates to the technical field of automobile braking and energy recycling and provides an automobile and a turbine braking system. The turbine braking system comprises a turbine braking device and an energy recycling system. The turbine braking device comprises a movable hub and a fixed hub. A closed cavity is defined by the movable hub and the fixed hub and filled with a fluid medium. The movable hub is provided with movable blades for driving the fluid medium. The fixed hub is provided with fixed blades for guiding the fluid medium. An inlet and an outlet are formed in the fixed hub. The energy recycling system comprises a drive pipeline, a circulating pipeline, a throttling device and a hydraulic motor. A circulating loop is formed by the drive pipeline, the circulating pipe and the closed cavity through the inlet and the outlet. By the adoption of the turbine braking system, the fluid medium is used as an energy transmission medium, the turbine braking device and the energy recycling system contain and are filled with the fluid medium, the braking energy generated by the turbine braking device is transmitted into the energy recycling system through the fluid medium and recycled, and the system has the beneficial effect that the energy consumption of the automobile is reduced.

The invention discloses a main shaft double-position positioning device for a rhombic metal mesh knitting machine, belongs to the technical field of rhombic metal mesh knitting machines, and aims to solve the problems of large impact force, inaccurate positioning and difficulty in repair in the existing positioning way. The main shaft double-position positioning device comprises a main shaft sensor system, a main shaft upper-position positioning electromagnet push rod system, a main shaft upper-position positioning electromagnet push rod system bracket, a main shaft low-position positioning electromagnet push rod system, a main shaft lower-position positioning electromagnet push rod system bracket and a molded structure of two interwoven flat spiral steel wires. By adopting the main shaft double-position positioning device for the rhombic metal mesh knitting machine, the problem that impact and vibration are generated since an electromagnet push rod is directly pressed against the radial surface of a cam without any energy dissipation process, the problems that positioning is inaccurate and adjustment is difficult since an electromagnetic brake has an energy dissipation process as well as a positioning function, and the problems of gasification of oil, pitting corrosion of material surfaces and difficulty in replacing sealing parts in the positioning way of a crank slider mechanism are solved.

The invention belongs to the field of transmission mechanisms for electric carriers, in particular to a power transfer mechanism of an electric carrier, which uses single rotating power source for respectively driving two planetary reduction modules and two output shafts to perform the differential output. The power transfer mechanism of the electric carrier comprises a shell, a motor stator, a first output shaft, a motor rotor, a first planetary reduction module, a second output shaft and a second planetary reduction module, wherein the motor stator, the motor rotor, the first planetary reduction module and the second planetary reduction module are respectively accommodated in the shell; the first planetary reduction module is connected with the first output shaft; the second planetary reduction module is connected with the second output shaft; and the first output shaft and the second output shaft are connected by a movable positioning mechanism, so that the first output shaft and the second output shaft respectively perform the differential output by the first planetary reduction module and the second planetary reduction module to achieve a differential effect of double output power sources by single power source.

The invention discloses a vacuum pipeline magnetic levitation train braking system and method. Inflation ports are arranged on a vacuum pipeline at intervals. When the pressure inside the pipeline reaches the atmospheric pressure is detected, the inflation ports are closed and the inflation is stopped; and brake wing plates are arranged at the top portions of train compartments, and the opening and closing of the brake wing plates are in cooperation with the opening and closing of the inflation ports for control. When a train sends an emergency braking signal, an air compressor inflate the pipeline through the inflation ports, meanwhile the brake wing plates at the top portions of the train are quickly opened, the air resistance is increased when the train moves, and the train deceleratesto achieve the braking purpose. The vacuum pipeline magnetic levitation train braking system has simple structure, safety and reliability. The emergency braking problem of the vacuum pipeline magneticlevitation train is solved, and stable, safe and effective braking of the train in a vacuum environment and without train wheels is ensured.

The invention relates to a dual-use device for shoveling and bulldozing, comprising a cab and a steering gear. The steering gear is provided with a shoveling device and a bulldozing device. The cab is internally provided with a brake gear and a seat positioning device. The shoveling device comprises a shoveling arm and a bucket which is detachably mounted on the shoveling arm. The steering gear is provided with a shoveling arm connecting device, and the shoveling arm is mounted on the shoveling arm connecting device. The bulldozing device and the shoveling device are mounted on a same shop truck at the same time, so that a shovel and a bulldozer are integrated, and manpower and material resources are saved; a supporting arm and air cylinder mounting shafts are connected through bolts and other equipment in the bulldozer, so that the dual-use device for shoveling and bulldozing can move more freely, and operation can be quite convenient.

The invention discloses a suspension system for an unmanned vehicle. The suspension system comprises a suspension axle, a driving axle and a braking axle; the suspension axle comprises a swing arm, two cross pull rods and a spring shock absorber assembly; the driving axle comprises a cage universal constant speed transmission shaft, a bearing, a handlebar head and wheels; and the braking axle comprises a brake caliber, a brake pad and a brake disc. The system well bears impact and torque under the combined action of the swing arm for bearing a longitudinal force, the cross pull rods for bearing lateral forces of the wheels and the spring shock absorber assembly for bearing the longitudinal force; and the driving axle and the braking axle are directly connected with the wheels through the swing arm, so that the structure is simplified and the transmission link is reduced. The suspension system has the advantages of simple, reasonable and compact structure, good shock absorption performance and the like, and can be applied to the unmanned vehicle or other independently driven vehicles.

The invention discloses a rotation door drive device. The rotation door drive device comprises a door frame and a drive device body arranged in the door frame. Left-right-symmetry first transmission cavities are formed in the door frame. The door frame is internally provided with cavities located in the lower sides of the first transmission cavities. A drive body sliding cavity located between thefirst transmission cavities in the left side and the right side is formed in the door frame. Second transmission cavities located in the upper sides of the first transmission cavities are formed in the door frame. A third transmission cavity located in the lower side of the drive body sliding cavity is formed in the door frame. The drive device body is arranged in the first transmission cavities.A drive body which is in sliding connection with the inner wall of the rear side of the drive body sliding cavity is arranged in the drive body sliding cavity, and the top wall of the drive body sliding cavity is fixedly provided with an electromagnet.

The invention discloses a braking system of an electric skateboard and belongs to the technical field of braking devices. The braking system comprises a rear wheel and a rear fork, wherein the rear wheel is installed on the rear fork, a connecting base is arranged on the rear fork, a braking plate is arranged on the connecting base and acts on the surface of the rear wheel, a torsional spring is arranged in the connecting base and acts on the braking plate, a plurality of braking rollers are arranged at the bottom of the braking plate, included angles formed by rolling trajectories of the braking rollers and the rolling trajectory of the rear wheel are greater than 0 degree but are smaller than 90 degrees, and an included angle formed by the rolling trajectories of every two adjacent rollers is greater than 0 degree but is smaller than 90 degrees. Abrasion caused by using a frictional brake is avoided, a protection effect is played on parts in the braking system, the service life is prolonged, and the riding safety is improved. In addition, the braking system is simple in structure, low in manufacturing cost and convenient to install and maintain, adopts a treaded braking plate and makes the braking plate in contact with the rear wheel, the braking rollers can brake the rear wheel, the braking flexibility is high, and operation is convenient.

The invention discloses a safe landing device adopting permanent magnets variable in magnetic field and magnetorheological fluids variable in area. The safe landing device is characterized by comprising a base, a worm, a worm wheel, winding drums and a deceleration descending device, the worm wheel and the worm are meshed together, the right end of the worm is connected with the winding drums, thedeceleration descending device is located on one side of the worm, and comprises a first shell, a second shell, a screw, a rotating disc and a moving disc, the two ends of the screw are connected with the first shell and the second shell correspondingly, moreover, the screw is connected with the worm wheel, the rotating disc is close to the second shell, the moving disc and the screw are meshed together, a sealing ring is arranged between the rotating disc and the moving disc, the portion among the first shell, the second shell, the rotating disc, the moving disc and the sealing ring is filled with the magnetorheological fluids, and one permanent magnet is arranged on each of the sides, deviating from each other, of the rotating disc and the moving disc. The safe landing device has the advantages that the structure is simple, the landing distance is large, moreover, adjustment can be performed according to actual conditions, the adaptability is higher, the comfort is good, moreover, the safety is higher, and the stability is better.

The invention discloses an anti-falling wall-attached elevator for a construction site. The anti-falling wall-attached elevator comprises a main frame body, a lifting frame, an elevator main body, ananti-falling structure and a protective fence, wherein a wall-attached mounting frame is arranged on the back of the main frame body, elevator guide rails are arranged on the left side and the right side of the main frame body, two speed reducing motors are arranged inside the lifting frame, a counterweight block is hung inside the main frame body through a sling, the anti-falling structure is arranged at the top of the elevator main body, and a sliding convex block is arranged on one side, close to the main frame body, of the elevator main body. According to the anti-falling wall-attached elevator for the construction site, a rack, the anti-falling structure, a main gear and an auxiliary gear are arranged, when the falling speed of the elevator main body is too high, a centrifugal block overcomes the elastic force of a pressure spring piece to be thrown outwards, a brake drum is driven to rotate, the brake drum can move towards the right side when rotating on a screw rod, moreover, acopper nut is driven to move rightwards, the copper nut presses a disc spring, the process of moving the brake drum rightwards is slowed down, and the purpose of braking is achieved.

The invention relates to a high-power hybrid braking expander. The high-power hybrid braking expander comprises an expander spindle, an expansion end and a fan braking end. The expander spindle comprises a spindle and a spindle housing. The two ends of the spindle are correspondingly and rotationally connected with the two ends of the spindle housing through bearings and are correspondingly connected with the expansion end and the fan braking end in a transmission manner. The expander spindle is provided with at least one spindle oil brake. Each spindle oil brake comprises an annular braking body and a braking body oil inlet pipeline. The spindle is rotationally connected with the annular braking bodies. An annular braking oil groove communicating with the corresponding braking body oil inlet pipeline is formed in the inner ring wall of each annular braking body. An oil supply and return opening is formed in the spindle housing. Compared with the prior art, according to the high-power hybrid braking expander, the spindle oil brakes and the fan braking end are utilized comprehensively for braking; and when by means of a low-temperature device process design, a pressurizing braking expander cannot be used and the high-power braking effect is needed, the requirement of the expansion end on the large load operation can be well met, and the braking power can reach 200 kw and can be adjusted according to the actual operation load of the expansion end.

The invention relates to the field of mechanical vibration and particularly relates to an electromagnetic vibrating feeder. The electromagnetic vibrating feeder comprises an electromagnetic vibrator (1), an electromagnetic vibrator base (2), a feeder bracket (3), a feeding hopper (4), a sieve plate (5), a vibration adsorber (6) and a feeding groove (7). By improving the electromagnetic vibrating feeder and additionally mounting the sieve plate (5) and the feeding hopper (4), purposes of separating materials and performing vibrating feeding are achieved. By improving a half-wave rectifying circuit of the electromagnetic vibrator and reversely connecting a diode, purposes of braking quickly and protecting a coil can be achieved.

The invention discloses an air exhaust brake butterfly valve control system and control method. The control system comprises an air exhaust brake butterfly valve, a PWM electromagnetic valve on a pressure relief pipe segment and an electronic brake pedal, wherein a pneumatic actuator of the air exhaust brake butterfly valve communicates with a driving air inlet pipe segment, the driving air inletpipe segment communicates with both an air supplying pipe segment and the pressure relief pipe segment, the air supplying pipe segment communicates with an air source device, the pneumatic actuator orthe driving air inlet pipe segment is provided with a pressure sensor, and the pressure sensor, the PWM electromagnetic valve and the electronic brake pedal are all in electric connection with an engine ECU. According to the air exhaust brake butterfly valve control system and control method, on base of the position of the electronic brake pedal, the engine ECU finds out the driving air inlet pressure calibration value and the pulse width value in sequence, the opening of the PWM electromagnetic valve is adjusted in real time till a pressure actual measurement valve is equal to the driving air inlet pressure calibration value, the air exhaust brake butterfly valve blocks air exhaust to achieve the purpose of braking under driving of air inlet pressure, and by means of the air exhaust brake butterfly valve control system and control method, the opening of the air exhaust brake butterfly valve can be controlled on base of brake requirement power.

The invention relates to a bogie for container transferring. Two walking wheel sets of the bogie are arranged oppositely in the length direction of a framework, each walking wheel set comprises two walking wheels, and the two walking wheels in each walking wheel set are rotatably arranged on the two sides of the width direction of the framework respectively; two driving motors are arranged at thetwo ends in the length direction of the framework respectively, and two gear boxes are fixed to the framework; each gear box is arranged between the corresponding driving motor and the walking wheel set, an input shaft of each gear box is in transmission connection with an output shaft of the corresponding driving motor, and two output shafts of each gear box are in transmission connection with rotating shafts of the two walking wheels of the corresponding walking wheel set; a braking part of each braking mechanism is arranged between the output shaft of the corresponding driving motor and theinput shaft of the corresponding gear box. The space of the bogie compact in structure can be reasonably utilized, so that the purpose of braking the bogie is achieved.

The invention relates to a brake mechanism of a baby stroller, which comprises a wheel bracket, wheels, a press block arranged on the wheel bracket in a mode of allowing for sliding up and down, and a lock rod arranged on the wheel bracket in a slidable mode; the wheels are connected with the wheel bracket in a rotatable mode; the wheels are provided with a plurality of locking grooves; the side part of the press block is in contact with one end of the lock rod; the side face of the press block is provided with a second guide inclined plane which pushes a connecting rod to slide along the horizontal direction; a reposition mechanism for locating the press block is arranged between the press block and the wheel bracket; the reposition mechanism for positioning the press block comprises a locating block arranged on the press block, a blocking piece, a poking hook arranged on the wheel bracket, and a pressure spring arranged between the wheel bracket and the press block to provide elastic force for the press block; a locking mechanism provided with a locking mode and a free mode allows the locking mechanism to carry out switch between the locking mode and the free mode by manipulation of the press block, thereby the application is convenient.

The invention discloses a single-damper single-resistor star-connection non-vibration brake frequency conversion device which comprises a frequency converter. The frequency converter comprises a power circuit, a rectifying circuit, an inverter circuit, a main control circuit, a driving circuit, a voltage sampling circuit and a current sampling circuit. The single-damper single-resistor star-connection non-vibration brake frequency conversion device further comprises a damping circuit and an electromagnetic valve. The three output ends of the damping circuit are connected with the electromagnetic valve in series and connected with the three output ends of the inverter circuit correspondingly, and the control input end of the electromagnetic valve is connected with the damping control signal output end of the main control circuit. The damping circuit comprises three resistors, one end of each resistor is connected with one end of another resistor, and the other ends of the three resistors respectively serve as the three output ends of the damping circuit. According to the single-damper single-resistor star-connection non-vibration brake frequency conversion device, the resistors in the damping circuit are used for consuming energy at the output ends, namely the load ends, of the inverter circuit so as to achieve the braking purpose, and no vibration, no noise, no overvoltage, no overcurrent and no temperature rise exists in the braking process. The single-damper single-resistor star-connection non-vibration brake frequency conversion device is an upgraded product of a traditional frequency converter.

The invention discloses a hydraulic brake circuit and a brake method. The hydraulic brake circuit comprises a motor, an energy accumulator, a front pump / motor, a rear pump / motor, a front pilot operated check valve, a rear pilot operated check valve and an electromagnetic reversing valve. On one hand, the motor is sequentially connected with the front pump / motor, the front pilot operated check valve and the energy accumulator, and on the other hand, the motor is sequentially connected with the rear pump / motor, the rear pilot operated check valve and a wellhead hydraulic cylinder. The electromagnetic reversing valve, the front pump / motor and the rear pump / motor are connected with an oil tank. The energy accumulator, the front pilot operated check valve and the rear pilot operated check valve are connected with the electromagnetic reversing valve. By the adoption of the hydraulic brake circuit, through the electromagnetic reversing valve and by the utilization of high-pressure loop fluid of the energy accumulator, the work states of the pilot operated check valves are controlled. The two pilot operated check valves are adopted to act synchronously, a hydraulic loop of the wellhead hydraulic cylinder and a hydraulic loop of the energy accumulator are closed and opened, and a wellhead hydraulic cylinder plunger can start and stop in any position.