165 results about "Retarder" patented technology

The utility model discloses a reaction kettle material adding and quantitative feeding device which comprises a reaction kettle main body and a feeding pipe installed on the top of the reaction kettle main body, a feeding bin is arranged on the top of the reaction kettle main body, a circular groove is formed in the feeding bin, a retarding motor is fixedly installed on the right side of the feeding bin, and the retarding motor is fixedly installed on the right side of the circular groove. An output shaft of the retarding motor penetrates through and extends into the circular groove, a rotating shaft is fixedly connected to the output shaft of the retarding motor, and the other end of the rotating shaft penetrates through and extends out of the feeding bin. According to the utility model, the slow-speed motor and the partition plate are matched to realize slow and equal-quantity conveying of materials and ensure that the feeding is accurate and controllable, and meanwhile, the single-time feeding quantity can be flexibly changed by adjusting the position of the movable seat, so that different process requirements are met; and through rotary sliding sealing treatment of a limiting plate and a circular groove and tight attachment of a through groove and a partition plate, it is guaranteed that no leakage exists in the conveying process, attached materials are convenient to clean through the left-right moving design of a movable base, and the equipment maintenance efficiency is improved.

The utility model relates to the technical field of vehicles, and particularly discloses a separation structure of a hydraulic retarder, the hydraulic retarder and a vehicle, a center shaft is provided with a matching groove, the extension direction of the matching groove is parallel to the axial direction of the center shaft, and a rotor assembly is provided with a matching block. The matching block is attached to the groove wall of the matching groove and can slide along the groove wall of the matching groove, and when the center shaft drives the rotor assembly to rotate, the groove wall of the matching groove pushes the matching block to slide in the direction close to the stator assembly. And the matching groove and the matching block are arranged, the extending direction of the matching groove is parallel to the axial direction of the center shaft, the structure is simpler, the requirements for machining equipment and personnel skills are low, and the machining cost is reduced.

The energy-saving speed reducer device comprises a speed reducer, a heat dissipation set is arranged on one side of the speed reducer, a pressure pump is arranged on the upper portion of one side of the heat dissipation set, the input end of the pressure pump is connected with the heat dissipation set, and the output end of the pressure pump is connected with an oil inlet of the speed reducer through a connecting pipe. An oil outlet in one side of the speed reducer is connected with the radiating group through an oil discharge pipe; according to the speed reducer, through arrangement of the pressure pump, lubricating oil in the speed reducer shell can be pumped out for cooling, so that the lubricating quality is improved, through arrangement of the heat dissipation set, the lubricating oil can be cooled, the service life of gears in the speed reducer is prolonged, and the energy loss is reduced; the outer side heat dissipation set can be fixed to the speed reducer and can be adjusted according to the size of the speed reducer, the height of the installation set can be adjusted through the arrangement of the adjusting set, and therefore the heat dissipation device is suitable for speed reducers of different sizes.

The application discloses a kind of air path structure and method for inhibiting pump gas loss of hydraulic retarder, belong to vehicle hydraulic auxiliary braking technical field;Air path structure includes air compressor and several air inlet jet devices;Several installation holes and several blades are processed on the fixed wheel of hydraulic retarder;Several blades are evenly distributed on the inner circumferential surface of fixed wheel along the circumference of fixed wheel;Several installation holes are evenly distributed between every two adjacent blades, one end of installation hole is connected with air path structure, and the other end is communicated with the working cavity of hydraulic retarder;Through hole is processed on each air inlet jet device;One end of all air inlet jet devices is merged into a pipeline, and is connected to the air outlet of air compressor by a gas pipe;The other end of each air inlet jet device is respectively and one-to-one installed in the installation hole of fixed wheel.The application injects high-speed air inlet jet into the inside of the working cavity of hydraulic retarder by air inlet jet device, reduces the flow speed of circulating air flow, to inhibit pump gas loss.

The invention provides a speed reducer, a vehicle and a quality detection method. The speed reducer comprises a speed reducer shell, and a containing cavity is formed in the speed reducer shell; the gear shaft is located in the containing cavity, bearing assemblies are arranged at the two ends of the gear shaft, the gear shaft is connected with the speed reducer shell through the bearing assemblies, the bearing assemblies and the gear shaft are arranged in an interference fit mode, and first mounting grooves are formed in the end faces of the bearing assemblies; and the elastic assembly is located in the first mounting groove, part of the elastic assembly protrudes out of the first mounting groove, and the elastic assembly makes contact with the speed reducer shell. The problems that in the prior art, a bearing outer ring creeps along with operation of a speed reducer, and abrasion is generated are solved.

The invention discloses a vehicle braking control method and device, a power domain controller and a vehicle, and relates to the field of vehicle control. The method comprises the steps that whether the execution condition of a downhill constant speed function is met or not is judged; if the execution condition is met, total braking force needed by the vehicle is determined; determining an electric braking force which can be provided by the vehicle at the current vehicle speed; controlling an electric brake to brake so as to provide electric braking force; and controlling the hydraulic retarder to brake so as to compensate the difference value between the total braking force and the electric braking force. The defect that the braking force of the electric brake is insufficient is made up through compensation of the hydraulic retarder besides the braking dominated by the electric brake. The braking force is distributed, so that the vehicle can run downhill at a heavy load according to a set vehicle speed, the economical efficiency of the whole vehicle is guaranteed, electricity feedback is utilized to the maximum extent, and the safety of the vehicle is also guaranteed.

According to the multi-medium circulating system based on the hydraulic retarder, a large circulating oil way, a small circulating oil way and an exhaust passage are highly integrated on a retarder shell and a heat exchanger bottom plate, and the large circulating oil way and the small circulating oil way share a large circulating oil outlet channel, a small circulating oil outlet channel and a heat exchanger; an oil outlet exhaust passage, a large-small circulation oil outlet passage and a heat exchanger bottom plate covered channel form an independent exhaust passage, so that gas and oil media achieve efficient cooperation in large-small circulation and exhaust circulation, and meanwhile all-working-condition performance optimization of high torque precision and high continuous braking capacity under the braking working condition and low air loss and low temperature under the idling working condition is achieved. Meanwhile, the oil way is integrally formed on the inner side of the retarder shell, so that the sealing reliability and the structural strength of the system are remarkably improved; the oil leakage and oil pumping faults of the oil duct are completely eradicated from the source, the idling loss and the working temperature are remarkably reduced, the torque control precision is improved, the system integration degree and the operation reliability are improved, and cost reduction and efficiency improvement are achieved.

The utility model relates to a railway retarder puller, including two connecting frames, the outside of connecting frame is all equal interval and is opened with adjusting hole, the inside of adjusting hole is all and is connected with the pivot of sliding, and the pivot is rotatably connected with two connecting rods between corresponding two, and the recess of two connecting frames is close to and is equipped with the first handle, and the top of first handle is rotatably connected with the first connecting rod. The utility model has the advantages that the cooperation and design of adjusting hole, pivot and connecting rod make the puller can adapt to different specifications of retarder, enhance the versatility of the device, the lever linkage structure that connecting rod, first handle and second handle form effectively reduces the force required for puller operation, improves the operation efficiency, and the cooperation mode of multi-component hinging guarantees the stability of clamping and puller process, prolongs the service life of the device.

The invention provides a lubricating structure of a retarder, which enhances the lubricating effect on a side oil seal of the retarder, reduces the ablation condition of the oil seal and prolongs the service life of the retarder. The retarder comprises: a retarder housing; the outer end of the transmission shaft is sleeved with a first bearing, and the inner end, corresponding to the position of the gearbox, of the transmission shaft is sleeved with a gear and a second bearing; a gearbox side oil seal; a retarder side oil seal; an oil seal seat; the pump comprises a pump shaft and a vane pump wheel; a partition sleeve; and a pump chamber mounting assembly.

The invention provides an underground trackless transport vehicle with an electromagnetic retarding system, and belongs to the technical field of mining transport vehicles. According to the underground trackless transport vehicle, vehicle operation parameters are collected in real time to establish a dynamic state matrix, speed and acceleration change characteristics are extracted by using a sliding time window method, risk working condition points are identified and are subjected to space-time alignment with a roadway position, and the risk working condition points are determined; a dominant working condition and a disturbance working condition are separated through singular value decomposition, a Pareto optimization model is adopted to solve a braking torque reference value, then a Stackelberg game model is utilized to carry out two-layer hierarchical collaborative optimization on an electromagnetic retarding device and a hydraulic braking system, and control parameters are corrected in real time through a dynamic compensation mechanism. The technical problem that an underground trackless transport vehicle is difficult to realize collaborative optimization control of an electromagnetic retarding device and a hydraulic braking system in a complex and changeable roadway slope environment is solved.

1. The name of the design product: hoisting tool (automatic transmission retarder). 2. The use of the design product: hoisting for retarder assembly, housing and main shaft. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view.

The present application relates to the technical field of hydraulic retarder, and particularly relates to an explosion-proof hydraulic retarder and a control method, which comprises a box, a rotor and a stator, the box is provided with an oil storage cavity for storing working oil, the rotor and the stator are provided with a working cavity in communication with the oil storage cavity, the box is provided with an air inlet and a plurality of air outlets, the air inlet is connected with an external air source to input compressed gas into the oil storage cavity, so that the working oil enters the working cavity, and the plurality of air outlets are used for combined exhaust to reduce the input amount of the working oil in the working cavity; the compressed gas input into the air inlet makes the working oil enter the working cavity to produce a retarding effect, then the exhaust of different air outlets is controlled to reduce the input amount of the working oil; since each air outlet is directly communicated with the oil storage cavity, when the exhaust valve acts, the air pressure in the oil storage cavity changes rapidly, and then the braking force of the retarder changes rapidly, so that the response speed is improved, and the use safety of the retarder is improved.

This invention relates to a controllable, low-loss hydraulic retarder, comprising a housing and a cover, an output shaft, and a fixed wheel, a driven wheel, a first clutch, and a second clutch disposed within the housing. The output shaft passes through the housing and the cover and is connected in series to the vehicle's main drivetrain. The driven wheel is fixedly connected to the output shaft. The first clutch is mounted on the inner wall of the housing and connected to the fixed wheel. The second clutch is mounted on the output shaft and connected to the fixed wheel. Under braking conditions, the engagement of the first clutch and the disengagement of the second clutch keep the fixed wheel stationary relative to the housing. Under non-braking conditions, the disengagement of the first clutch and the engagement of the second clutch cause the fixed wheel to rotate synchronously with the output shaft and the driven wheel. A second control valve is provided on the housing to regulate the pressure and oil volume within the housing. This invention controls the engagement and disengagement of the two clutches to change the motion state of the fixed wheel, thereby minimizing losses under non-braking conditions.

The scheme relates to the field of rail transit locomotive braking, and discloses a rail transit mechanical, electrical and hydraulic three-stage combined braking control method and a control system. The control method steps are as follows: a power split motor train unit including two or more than two power sources of internal combustion and electricity is used, one or several brakes of mechanical braking, electrical braking and hydraulic braking are selected according to the opening degree of the brake handle on the motor train unit, and the selected brake is used for braking. The control system includes a hydraulic retarder, a traction motor, a traction inverter, a mechanical transmission box, a clutch, an axle gear box, mechanical brake shoes, an energy storage device and a controller. Through the mechanical, electrical and hydraulic three-stage combined braking mode, the risk of braking failure caused by mechanical braking wear is further reduced, and the reliability and comfort of the braking system are improved.

The invention discloses a hydraulic retarder for a special vehicle based on oil pump control, and relates to the technical field of vehicle braking, the hydraulic retarder comprises a working assembly, an oil storage tank and an oil pump, a stator and a rotor are arranged in the working assembly, the rotor is connected with a vehicle transmission system through a power output shaft, and one end of the oil pump is connected with an oil inlet of a proportional pressure reducing valve; compared with an existing hydraulic retarder, the hydraulic retarder is provided with the transmission mechanism and the gear assembly, the power of a vehicle transmission system can be efficiently and controllably transmitted to the oil pump through the power output shaft, the transmission mechanism and the gear assembly, and the oil pump can efficiently receive the power and drive oil liquid to circulate; and through cooperation of the proportional pressure reducing valve and the transmission mechanism, bidirectional control over the oil supply amount of the oil pump is achieved, the braking reliability is greatly improved, the situation that the braking efficiency is reduced due to faults of a single adjusting mechanism is effectively avoided, and the braking requirement of the special vehicle under the complex working condition is met.

The invention discloses an electric retarding control system and method and a pure electric vehicle. The system comprises a vehicle control unit, a motor controller and an electronic braking system. The vehicle control unit is used for calculating real-time deceleration according to wheel speed information fed back by an electronic braking system when an electric retarding function is started, the vehicle control unit is located at the maximum retarder gear and brake pedal information exists, filtering the real-time deceleration, and outputting the filtered real-time deceleration to the electronic braking system. Calculating a target deceleration according to the filtered real-time deceleration and the deceleration compensation value, and sending the target deceleration to the electronic braking system to enable the electronic braking system to perform smooth braking; wherein the electric braking torque corresponding to the maximum retarder gear is smaller than the current maximum available torque of the motor. According to the invention, the idle stroke phenomenon of the brake pedal generated when a driver steps on the brake pedal due to electric braking saturation and the problem of braking force step caused by abrupt intervention of air braking are avoided.

A multi-speed transmission including a plurality of planetary gearsets and a plurality of selective couplers is disclosed. The multi-speed transmission may include a retarder including a retarder housing, a rotor positioned in the retarder housing and fixedly coupled to a portion of the plurality of planetary gearsets, and a stator positioned in the retarder housing and fixedly coupled to at least one stationary member.

The invention relates to the technical field of hydraulic retarders, and discloses a shell structure of a hydraulic retarder, which comprises a front shell, a sealing base plate and a rear shell, the front shell and the rear shell are buckled in a matched mode, and the sealing base plate is clamped, sealed and fixed between the front shell and the rear shell through bolts. The front shell comprises a first cavity and a second cavity, and the first cavity is formed in the outer surface of the front shell; a second cavity is formed in the inner surface of the front shell; the first cavity and the second cavity are directly communicated through a first inter-cavity communication part, a second inter-cavity communication part and a third inter-cavity communication part respectively; the surrounding part structure of the second cavity of the front shell, the sealing base plate and the surrounding part structure of the inner surface of the rear shell jointly form a control oil duct of the hydraulic retarder. A first cylindrical oil duct and a second cylindrical oil duct are formed in the outer surface of the rear shell, and the first cylindrical oil duct and the second cylindrical oil duct can communicate with the heat exchanger; high-integration design of the retarder can be achieved, and the response speed and reliability of a retarder assembly are improved.

The application discloses a kind of pure electric wide-body car downhill active speed stabilization safety control system, method and vehicle, comprising: slope sensor, for real-time acquisition vehicle driving road slope signal;Vehicle speed acquisition module, for real-time acquisition vehicle driving speed signal;Vehicle controller is electrically connected with the slope sensor, vehicle speed acquisition module, vehicle energy recovery system, electric eddy current retarder and emergency brake solenoid valve respectively;The vehicle controller built-in control program is used to receive the slope signal and speed signal, according to the intervention condition judgment logic of pre-set, automatically control the intervention or exit of energy recovery system, electric eddy current retarder and emergency brake solenoid valve, realize the active speed stabilization when vehicle heavy downhill.This application can actively control each set of brake system, and realize the linkage between each brake system, make full use of each set of brake system characteristics, achieve speed stabilization effect.

This invention provides a method and system for life testing of a transmission mechanism in a vehicle reducer. The method includes: assembling the transmission mechanism under test with a braking mechanism; placing a load on a track, such that the load can be subjected to force by the braking mechanism in a braking state, wherein the load simulates a vehicle, and the load's velocity relative to the track along the track's extension direction is 0 when placed on the track; controlling the transmission mechanism under test to drive the braking mechanism to move, causing the braking mechanism to continuously switch between a braking state and a releasing state; collecting state data of the transmission mechanism under test when it drives the braking mechanism; and determining the lifespan of the transmission mechanism under test based on the state data. The method provided by this invention can relatively accurately simulate the actual working state of the transmission mechanism under test, obtain state data of the transmission mechanism under test, and, by analyzing the state data, can relatively accurately detect the lifespan of the transmission mechanism.

An NBR composition, that is excellent in rubber material processability and vulcanized rubber hardness, comprising 93 to 105 parts by weight of carbon black with a carbon black grade of N330 or N550, 1.0 to 4.0 parts by weight of a vulcanization retarder, 2.0 to 5.0 parts by weight of thiazole-based and thiuram-based vulcanization accelerators, and 1.0 to 4.0 parts by weight of a sulfur-based vulcanizing agent, based on 100 parts by weight of NBR. The vulcanized molded product obtained from the NBR composition has a rubber hardness (Duro A, instant) of 85 or more according to JIS K6253 corresponding to ISO 18517, and can be effectively used as an automobile buffer material such as a stopper for electric power steering, a buffer material for nailers, a buffer material for devices equipped with hydraulic cylinders, or the like.

The invention relates to methods for limiting the braking power of a motor vehicle braking system with a hydrodynamic retarder having a working chamber arranged between two paddle wheels, which can be filled with a working medium or is filled to transfer drive power hydrodynamically from one paddle wheel to the other, thereby braking one paddle wheel and a drive shaft connected to one paddle wheel; with an external working fluid circuit connected to the working chamber via a working fluid inlet and a working fluid outlet, comprising an oil-water heat exchanger with which heat is transferred from the working fluid, which comprises oil, to a vehicle cooling circuit; wherein the braking power of the hydrodynamic retarder is reduced depending on a detected current temperature in the vehicle braking system. The method according to the invention is characterized in that the current temperature of the working medium is detected and, if the detected temperature of the working medium exceeds a predetermined constant working medium temperature limit, the current braking power of the retarder is reduced in such a way that the working medium temperature adjusts to the predetermined working medium temperature limit.

The application provides a control method and a control device for a high-viscosity oil retarder, comprising the following steps: in response to a received first gear engagement operation, determining a first retarder gear position of the high-viscosity oil retarder; then determining a first initial opening degree of a first flow control valve and a second initial opening degree of a second flow control valve according to the first retarder gear position; and by controlling the on-off electricity of a first electromagnetic valve, a second electromagnetic valve and a third electromagnetic valve, changing the pressure in a working cavity in the retarder body in the process of sucking or pumping the high-viscosity oil into the working cavity in the high-viscosity oil retarder body according to a target pump oil amount corresponding to the first initial opening degree and discharging the high-viscosity oil from the working cavity according to a target oil discharge amount corresponding to the second initial opening degree, so as to slow down the speed of the vehicle to a driving speed corresponding to the first retarder gear position. In this way, by controlling the on-off electricity of the electromagnetic valves and adjusting the opening degrees of the flow control valves, the pressure in the working cavity is adjusted, so that different braking effects are realized, and different braking requirements are met.

The utility model discloses a railway station yard speed regulation hydraulic parking device relates to railway parking field. The utility model discloses a railway station yard speed regulation hydraulic parking device, and the quick detachable parking device support subassembly including support base plate, slope type guide side plate, bottom limit clamp, detachable limit clamp, support base, concave type installation slot and U type limit installation board that set up can carry out sectional type alignment installation to hydraulic parking device, is convenient for its transportation and installation work has better deployment efficiency, and the two -stage speed regulation buffer type hydraulic parking subassembly including middle part hydraulic buffer base, secondary buffer base, connecting base, hydraulic oil tank, middle part hydraulic extension rod, lateral hydraulic extension rod, limit ring, limit sliding sleeve and parking support plate that set up can carry out sectional type absorption work according to the kinetic energy of vehicle transmission when using, and the energy absorption parking effect of improving is improved through the secondary kinetic energy absorption to it.

A drive motor and a retarder in a powertrain meet a condition that a harmonic order of the drive motor is the same as a quantity of gear teeth of an input shaft gear in the retarder such that a frequency of an electromagnetic noise harmonic generated by the drive motor is the same as a frequency of a noise harmonic generated by the retarder. When the drive motor and the retarder are coupled using a connection structure, a phase of the electromagnetic noise harmonic generated by the drive motor differs from a phase of the noise harmonic generated by the retarder by a set angle.

This application relates to a retarder power master switch, comprising a housing and a bracket. The housing is hollow, forming a receiving cavity. Two stationary contacts are disposed on the bottom wall of the receiving cavity, extending out of the housing as a first contact and a second contact. The housing is fixedly connected to the bracket, which has a fixing block. A fuse and a protective shell are mounted on the fixing block, and multiple spare fuses are disposed on the protective shell. A third contact and a fourth contact are disposed on the fixing block, with both ends of the fuse fixedly connected to the third and fourth contacts. A power line is disposed between the first and third contacts. The fourth contact is used for a secure connection to the positive or negative terminal of the battery, and the second contact is used for connection to the main circuit of automotive electrical equipment or a relay control terminal. This application effectively solves the problem of the vehicle's electrical system being unable to quickly restore power after a traditional power master switch fuse blows, through the use of a protective shell and spare fuses.

The application discloses a pinion shaft for an electric vehicle speed reducer and belongs to the technical field of pinion shafts.The pinion shaft comprises a pinion shaft body, wherein the pinion shaft body comprises a positioning portion, a fixing portion and a connecting portion, the bottom of the positioning portion is fixedly provided with a shaft tooth seat, the outer wall of the positioning portion is provided with a positioning groove, the shaft tooth piece is slidably sleeved with the positioning groove through the positioning groove, and the bottom of the shaft tooth piece abuts against the top of the shaft tooth seat.The positioning groove is used for facilitating the sliding sleeve connection of the shaft tooth piece on the outer surface of the positioning portion, the fixing screw is used for facilitating the fixed assembly of the fixing piece and the fixing portion, the shaft tooth piece is abutted against by the shaft tooth seat and the fixing piece, the fixed installation between the shaft tooth piece and the positioning portion can be completed, the shaft tooth piece is conveniently installed and dismounted, when the shaft tooth piece is worn after the long-time use of the pinion shaft, the shaft tooth piece only needs to be replaced, the whole pinion shaft does not need to be replaced, the pinion shaft can be repeatedly used, and cost is saved.

The utility model provides an electromagnetic retarding four-motor two-gear mining dump truck gearbox. The electromagnetic retarding four-motor two-gear mining dump truck gearbox comprises motors, an input tooth set, a connecting tooth set, a transmission tooth set and an output tooth set which are connected in sequence, the multiple motors are converged into the connecting tooth set through the input tooth set and transmitted to the transmission tooth set through the connecting tooth set, the transmission tooth set is provided with two gear shifting mechanisms, and the two gear shifting mechanisms are connected with the output tooth set. The gear shifting mechanism is connected with the output gear set, and the output gear set is provided with an electromagnetic retarder. The electromagnetic retarding four-motor two-gear mining dump truck gearbox solves the problem that an existing product cannot meet the use requirement.

The magnetic car arrester comprises a triangular base, magnets are arranged at the bottoms of the two sides of the triangular base, baffles are laid on the two sides of the inclined face of the triangular base, wheel clamping grooves are oppositely formed in the middles of the baffles on the two sides, wheel blocking strips installed on the surfaces of the baffles are arranged on the sides, close to the edge of the triangular base, of the wheel clamping grooves, and fan-shaped baffles are arranged on the two sides of the triangular base. The circle center point end of the fan-shaped baffle is rotationally connected to the side face of the triangular base through a bolt. The magnet is arranged at the bottom of the triangular base for adsorption, the car stopping effect is stable, and the situation that the car stopper is propped out of a rail when a car moves is avoided. The wheel clamping grooves are grooved according to the distance positions of the wheels of the mine vehicle, the wheels are clamped into the grooves during vehicle stopping, the cross sections of the wheels can make contact with the vehicle stopping strips more quickly, and rapid vehicle braking and stopping are achieved. The vehicle stopping strip adopts a step-shaped surface, so that the sliding allowance of the vehicle can be effectively buffered. The design of the fan-shaped baffles on the two sides can effectively avoid the technical problem that the car arrester slides off from a rail due to accidental movement of a car or external touch.

The invention relates to the technical field of automobile auxiliary braking, and discloses an electro-hydraulic composite retarder with a straight blade structure, which comprises a rotor, a stator, a stator connecting piece and a magnet exciting coil. The rotor is of a double-tooth type structure, radial blades and semicircular hydraulic circulation liquid channels are arranged on the two end faces of the rotor, and salient pole teeth are arranged on the outer circumferential end face of the rotor. A hydraulic circulation liquid channel matched with the rotor liquid channel is formed in the end face of the stator, and a hydraulic working cavity is formed; the stator connecting piece is of a hollow cylinder structure, the two ends of the stator connecting piece are fixedly connected with the left stator and the right stator respectively, and a liquid outlet is formed. The excitation coil is fixed on the inner side of the stator connecting piece and located at an axial gap of rotor teeth, the rotor and the stator connecting piece are made of magnetic and conductive materials, the synergistic effect of hydraulic braking and eddy current braking is achieved, and the composite retarder which is high in braking power density at the full-speed section, fast in response, compact in structure and convenient to machine and assemble is obtained.