143results about How to "Avoid brake failure" patented technology

This invention provides caliper covers having vent openings, caliper cover kits, and methods for cooling caliper brake mechanisms that prevent brake fade and prevent brake malfunction caused by debris from the road, while improving the appearance of the caliper braking mechanism and preventing transfer of braking dust from the brake pads to the wheels.

The invention relates to an automobile hub temperature anomaly detection and early warning method and system. The system comprises a surveillance camera, a thermal infrared imager, a control host and a variable information board. The surveillance camera is installed above a road, the thermal infrared imager is installed on the road side, and the variable information board is arranged on the downstream of the surveillance camera. When a vehicle arrives at a detection area, the surveillance camera and the thermal infrared imager collect images of the vehicle and send the images to the control host; the control host carries out vehicle license plate recognition on the image shot by the surveillance camera; the control host extracts and fuses the SBDD, HOG and LBP features of a hub in the thermal imaging image and then judges whether the temperature of the hub is abnormal or not in a classified mode through an incremental support vector machine; when it is found that the temperature of the hub is abnormal, vehicle information is sent to the variable information board for early warning reminding. By means of the automobile hub temperature anomaly detection and early warning method and system, whether the temperature of the hub of an automobile is abnormal or not can be effectively detected, and early warning can be effectively carried out, so that traffic accidents caused by brake failure, fire breakout, tire burst and the like are avoided.

The invention discloses a vehicle braking stability control method and system. The method includes the following steps that the actual yaw velocity of a vehicle is acquired; a target yaw velocity of the vehicle is calculated; the difference between the target yaw velocity and the actual yaw velocity and the absolute value of the difference are calculated; according to the absolute value, the braking states of the vehicle are judged, wherein the braking states includes stable braking and instable braking; when the braking state of the vehicle is instable braking, braking instability types of the vehicle are judged according to the difference, wherein the braking instability types include over-steering and insufficient steering; the slip rate of wheels is calculated; according to the brakinginstability type of the vehicle and the slip rate of the wheels, the brake force of the wheels on one side is controlled to be increased or the brake force of the wheels on the other side is controlled to be reduced. According to the method, when the vehicle is instable in the steering braking process, the situation that the brake force is excessively increased, an anti-lock braking system of thevehicle is activated and accordingly braking fails is avoided, and the stability of a vehicle body is greatly improved.

The invention provides a high-voltage circuit of an electric vehicle power battery and a failure processing method. The failure processing method is applied to a battery management system of an electric vehicle without depending on a vehicle control unit. The failure processing method includes the steps that when the power battery has a serious failure, if the speed of the electric vehicle is larger than a speed threshold value, the failure duration of the power battery is larger than first preset duration, connection between first-grade electric parts, such as a power-assisted steering pump and a brake air pump, of the electric vehicle and the power battery is kept by controlling a contactor in the high-voltage circuit of the electric vehicle power battery, it is avoided that the power battery has the failure to cause the vehicle high-voltage outage leading to steering failure or brake failure, and drive safety is ensured; meanwhile second-grade electric parts of the electric vehicle are disconnected from the power battery to ensure safety of the power battery.

The invention relates to a heat pipe radiation and thrust generation device and a production method thereof, which not only can be used for rapidly transmitting heat generated in a braking process outside to rapidly radiate heat for cooling, but also can be used for generating the directional thrust simultaneously while radiating the heat. An evaporation end and a condensation end of the heat pipe are cylindroid box-shaped cavities which are connected by a round connection pipe. A liquid suction core is arranged at the inner side of the connection pipe, the evaporation end is provided with a hole through which an infusion pipe is conveniently inserted and tightly welded, and the infusion pipe is sealed by a way of cold-welding sealing at first and welding later. The invention further provides a production method of a heat pipe applied to an automotive brake pad. The method comprises the steps of: material selecting, mechanical processing, cleaning, assembling, leakage detecting, vacuumizing, working medium injecting, sealing-in and inspecting. By applying the heat pipe to a brake pad heat radiator, not only can the problem about the heat fading of the brake pad be effectively solved, but also the new direction for developing a bake pad heat radiator is provided.

The invention discloses a brake fluid filling device and method. The brake fluid filling device comprises a fluid storage tank, and the fluid storage tank is connected with a raw fluid barrel through a fluid inlet pipe; the upper part of the fluid storage tank is connected with a vacuum pumping device; the outlet end of the fluid inlet pipe enters the fluid storage tank; a fluid-air dispersing mechanism is arranged at the outlet of the fluid inlet pipe in the fluid storage tank. The filling method is realized through the filling device. According to the brake fluid filling device and method, when complementing the raw braking fluid, the raw fluid enters the fluid inlet pipe from the raw fluid barrel to enter the fluid storage tank; the raw braking fluid falls or sprays to the fluid-air dispersing mechanism, and water molecules and air in the raw braking fluid are discharged into the fluid storage tank after being dispersed; the vacuum pumping device pumps air from the fluid storage tank and discharges the air and water molecules in the air from the fluid storage tank, the dry degree and pure degree of the braking fluid are improved, the vehicle braking effectiveness is improved, and the vehicle performance is improved.

The invention provides a fault early warning trailer axle, which belongs to automobile components, and in particular relates to an automobile trailer axle. The device comprises an outer bearing and an inner bearing which are sleeved on two ends of an axle, wherein hubs are sleeved on the outer bearing and the inner bearing respectively; a brake drum and the hubs are pressed together through bolts; a brake sheet is arranged on a brake bottom plate; the brake bottom plate is fixed on the axle; a camshaft is clamped by the brake sheet; the camshaft is movably arranged on the brake bottom plate; and an adjusting arm is sleeved on the camshaft. The trailer axle is characterized in that a heat sensor seat is arranged in a cavity formed by the brake drum and a dust cover; a heat sensor is arranged in the heat sensor seat; and the heat sensor is in electrical connection with a vehicle instrument panel. The trailer axle has the advantages that the heat sensor can rapidly sense the temperature change of the bearings and the brake drum in time, so as to effectively prevent axle overheat from damaging components, reduce the fault rate of vehicles, reduce the cost for maintaining and treating vehicle faults, prevent the brake sheet from being overheated and softened so as not to cause brake failure and guarantee driving safety; and the trailer axle is compact and reasonable in structure, easy to machine and implement, strong in practicability, stable in performance, safe and reliable.

The invention discloses an electric automobile and a brake control method. According to the electric automobile, an electronic control unit is connected with a main brake system, an auxiliary brake system, a brake execution system and a range radar; the main brake system and the auxiliary brake system are connected in parallel and then connected with the brake execution system; the main brake system is connected with a pedal through a brake rod and drives the brake execution system to execute a brake instruction transmitted by the pedal; a pipeline through which the main brake system is connected with the brake execution system is provided with a pressure sensor; the electronic control unit receives a distance abnormal signal of the range radar and a main brake system hydraulic abnormal signal sent by the pressure sensor, and the auxiliary brake system is controlled to drive the brake execution system to carry out braking. According to electric automobile and the brake control method through cooperation of the main brake system and the auxiliary brake system, the brake safety performance of the automobile is improved.

The invention discloses a liquid damping type braking system which comprises at least one pair of engaged gears arranged in a sealed gearbox, a gear axle penetrating out of the gearbox and connected with an external driving shaft, flowing channels arranged on the two sides of the gears, a braking liquid circulating channel which is formed in the manner that the braking liquid circulating channel penetrates out of the gearbox and is connected with a braking liquid storing box, and at least one braking switch valve arranged on the liquid inlet flowing channel of the braking liquid storing box. The purpose of decelerating braking is achieved by controlling the opening and closing states of the braking switch valve. The gearbox is structurally transformed and then applied to the braking field, the problems that a traditional friction braking material is large in abrasion, poor in braking effect, high in braking cost and the like are solved, and the phenomenon that braking fails due to heating in traditional friction braking is effectively avoided; and the liquid damping type braking system is simple in structure, low in manufacturing cost, convenient to use and maintain, easy to operate, capable of easily conducting braking, easy to control and safe and reliable in braking, any braking characteristic curve needed by equipment can be formed, and practical needs are met.

The invention discloses a motor vehicle emergency alarming and brake stopping device. A signal output end of a sensor is connected with a signal input end of a signal receiver, a signal output end of the signal receiver is connected to two ends of a coil of a contactor D through a switch K3, one end of a normally-open contact D1-1 of the contactor D is connected to the positive electrode of a direct current power source E through a power source switch K1, the other end of the normally-open contact D1-1 of the contactor D is connected to one end of a coil of a relay J, and the other end of the coil of the relay J is connected to the negative electrode of the direct current power source E. One end of a normally-open contact J1-1 of the relay J is connected to the positive electrode of the direct current power source E, and the other end of the normally-open contact J1-1 of the relay J is connected to one end of an electromagnet coil L on a vehicle brake. Two ends of a normally-closed contact J1-1 of the relay J are parallelly connected with a switch K2 and then connected to the positive electrode of a motor vehicle computer or the positive electrode of an ignition coil. By arranging the motor vehicle emergency alarming and brake stopping device on a motor vehicle, when the distance between barriers and vehicle is within the sensing range of the sensor, the vehicle can automatically perform emergency brake or flame out timely to avoid traffic accidents.

The invention relates to an electric pneumatic breaking type rapid air charging device for a replenishing compressed air. The electric pneumatic breaking type rapid air charging device is characterized in that two locomotive air compressors are connected in parallel and are connected with a total air cylinder; the total air cylinder is connected with a serial maneuvering device; the serial maneuvering device is connected with a braking main pipe; a relief air cylinder is connected with an electric pneumatic distribution valve through a relief air pipe; a control cable is connected with the electric pneumatic distribution valve through a branched control bypass A and is connected with an air compressor capable of stabilizing output pressure through a branched control bypass B; an air compressor body is connected with an air compressor motor, and a motor support seat is arranged under the air compressor motor; electric power connectors A are arranged at two ends of a locomotive or a vehicle; electric power connectors B are arranged at two ends of the locomotive or the vehicle; a bridging wire A is connected with the electric power connectors A of the locomotive and the vehicle or two adjacent vehicles; a bridging wire B is connected with the electric power connectors B of the locomotive and the vehicle or two adjacent vehicles; and the control cable is connected with the bridging wire B through the electric power connectors B at the joints of sections of the vehicle.

The invention provides a high-performance non-asbestos brake pad, and further provides a method for preparing the high-performance non-asbestos brake pad. The high-performance non-asbestos brake pad is at least prepared from the following components in parts by weight: 40-60 parts of fibers, 10-15 parts of resin and 35-40 parts of frictional powder. The non-asbestos brake pad is free of asbestos and is healthy and environmentally friendly, meanwhile, waste of non-asbestos clutch surface production is used as the frictional powder to turn the waste into treasure, the production cost, and wastedischarge is reduced.

A cooling system for the engine and hubs of car is composed of water cooling mechanism, temp control unit, water level controller and indicator unit. All the units are controlled by electric controller. Its advantages are high automatic level, adjustable pressure of cooling water, high cooling effect and less consumption of water.

The invention relates to an automatic water cooling device of a vehicle bridge, belongs to an automobile accessory, and in particular relates to a vehicle bridge cooling device. The device comprises a vehicle water tank; and a water pipe is respectively connected with the water tank and a nozzle. The vehicle bridge cooling device is characterized in that an electromagnetic valve is arranged on the water pipe; one end of the electromagnetic valve is connected with the water tank; the other end of the electromagnetic valve is connected with the nozzle; the nozzle is fixed on a vehicle bridge dustproof hood and faces towards a brake drum; a temperature sensor is fixed on a vehicle axle in the brake drum of the vehicle bridge; the temperature sensor is externally connected with an amplifying circuit; and the amplifying circuit is connected with the electromagnetic valve. When the temperature of the vehicle bridge is abnormal, the electromagnetic valve is automatically opened, and water is injected out for cooling; and when the temperature is normal, the electromagnetic valve is automatically closed. The vehicle bridge cooling device has the advantages of novel concept, simple and reasonable structure, easy processing and convenient maintenance, can accurately detect the temperature of the brake drum of the vehicle bridge and a bearing in time, cool the vehicle bridge in time when the temperature is abnormal, effectively avoid the faults that the bearing is burned down, a brake is out of order and a tire is blown out caused by abnormal temperature of the vehicle bridge and ensure safety of vehicle driving.

The invention discloses a high-reliability EMB brake-by-wire system and a control method thereof. The high-reliability EMB brake-by-wire system comprises an electronic control unit, a braking unit andan auxiliary energy recovery unit, wherein the electronic control unit receives a brake pedal signal to control the brake-by-wire system to perform braking, the braking unit comprises a first motor and a second motor, is used for performing braking force and reset, and completes the braking process; and the auxiliary energy recovery unit is composed of a rubber disk, a bevel gear group and a third motor, and recovers part energy in the braking process to charge a battery. A double-motor redundant structure is adopted by the braking unit of the brake-by-wire system, the first motor rotates positively and the second motor rotate reversely during normal working, the frequent positive and reverse rotation of the motors is avoided in the braking process, the service life of the motors is prolonged, and the braking response rate of the motors is improved; one motor fails and the other motor brakes alone to ensure the braking reliability; and the auxiliary energy recovery unit is adopted tocharge the battery of the drive-by-wire system to ensure the stability of the electric quantity of the braking system, energy is saved, and the energy consumption of the system is reduced.

The invention discloses a rotary braking system and a tower crane control system. The rotary braking system comprises a rotary braking circuit and a rotary eddy current braking circuit, wherein the rotary braking circuit comprises a switch, a first transformer, a rectifying circuit, a brake switch and a first storage battery; the switch is automatically switched on when sudden power failure of the power grid is caused or when the power grid fails; the first transformer is connected in series between the power grid and a rotary braking power supply of the tower crane; the first storage battery is connected to the rotary braking power supply by virtue of the switch and the brake switch; the rotary eddy current braking circuit comprises a power grid power supply circuit and a storage battery power supply circuit; and the storage battery power supply circuit comprises a second transformer connected in series between the power grid and an eddy current coil of the eddy current motor, a rectification filter circuit, a charging circuit, a second storage battery, an internal control relay, and a relay control circuit connected with the internal control relay. According to the systems disclosed by the invention, the eddy current braking failure and out-of-control risk caused by the power failure or fault of the power grid can be effectively avoided.

Provided is an airtightness detection system of an automobile pneumatic brake system. The system comprises a pneumatic brake system and an Internet of Vehicles system, the pneumatic brake system comprises an air pressure sensor used for acquiring air pressure data of a brake system front loop, a brake system back loop, and a brake system parking loop, the Internet of Vehicles system comprises a vehicle terminal and a networking platform, the vehicle terminal is electrically connected with the air pressure sensor, the vehicle terminal is connected with the networking platform in a signal manner, the vehicle terminal is used for receiving air pressure data transmitted by the air pressure sensor during vehicle shutdown and re-start and transmitting the air pressure data and moment data corresponding to the vehicle shutdown and re-start to the networking platform, and the networking platform is used for calculating a parking duration and an air pressure drop during a parking period, comparing the air pressure drop with a set threshold, and making an airtight determination. According to the design, the accuracy of airtightness detection of the pneumatic brake system is improved, and thereliability is high.

The invention discloses a parking brake device and a road roller. The parking brake device is mounted on a frame and is close to a bulge wheel of the road roller. The parking brake device is composedof a mounting base, a stopping shaft, a positioning spring, a positioning pin, retainer springs, a cylinder sleeve and a handle, wherein a guide groove is formed in the cylinder sleeve and is composedof an upper stop position, a lower stop position, a mounting groove, an upper rotating groove, a lower rotating groove and a moving groove; the upper rotating groove and the lower rotating groove communicate with the moving groove; the mounting groove is positioned on the moving groove; an axial distance exists between the upper stop position and the lower stop position; under the action of the spring force of the retainer springs, the stopping shaft can be locked on the upper stop position and the lower stop position so as to realize extension and retraction of the stopping shaft; when the stopping shaft extends to a gap between two bulges of the bulge wheel, the rotation of the bulge wheel is stopped so as to realize brake; and when the stopping shaft retracts, the brake is relieved. The parking brake device provided by the invention is simple in structure, easy to operate, reliable in brake and convenient to maintain and can avoid brake failure caused by vibration so as to improvethe safety of the road roller.

The invention discloses an air-cooling and water-cooling double-acting disc type braking device which comprises a brake disc and a brake block, wherein the brake disc comprises a brake disc substrate; the brake disc substrate comprises an inner side annular disc part and an outer side annular disc part; a hub is fixedly connected with the inner side annular disc part; a plurality of fan-shaped grooves are distributed in each of the two sides of the outer side annular disc part; fan-shaped bulges are arranged on one side of a asbestos-free friction plate and mounted in the fan-shaped grooves; a plurality of axial through holes are uniformly distributed in the inner side annular disc part; radial through holes are formed in each of the inner side annular disc part and the outer side annular disc part; one end of each of the radial through holes is communicated with the corresponding axial through hole; the other ends of the radial through holes directly penetrate through the outer circular surface of the outer side annular disc part; a plurality of cooling water channels are formed in the brake block. According to the air-cooling and water-cooling double-acting disc type braking device, during the braking process, heat absorbed by the brake block is taken away by cooling water, heat absorbed by the brake disc is taken away through heat dissipation channels formed by axial ducts and radial ducts, so that the brake disc can maintain a lower temperature.

The invention discloses a brake block holder and a braking device. The brake block holder comprises a holder body, a roller and a roller shaft, wherein the holder body is provided with an anti-run wing plate which is used for blocking the roller from rolling out of a side frame chute of a bogie. Through the anti-run wing plate arranged on the holder body, no matter what adverse working condition is, the brake block holder can ensure that the roller always rolls inside the side frame chute of the bogie, thereby effectively avoiding brake beam component falling caused by the roller rolling out of the chute, preventing braking failures, and improving the driving safety.

The invention discloses a safety vehicle speed prediction method and system and a vehicle-mounted terminal. The method comprises the following steps of acquiring road condition information and vehicleinformation of a tested vehicle on a continuous downhill road section; obtaining the initial brake drum temperature, the initial coordinate position and the emergency braking frequency of the testedvehicle running at the preset distance interval; according to the road condition information, the vehicle information, the initial coordinate position, the initial brake drum temperature and the emergency braking frequency, calculating second brake drum temperature after the preset distance interval is completed; acquiring the second coordinate position of the vehicle after the vehicle completes the preset distance interval; calculating the safety speed of the tested vehicle according to the road condition information, the vehicle information, the second brake drum temperature, the second coordinate position and the preset temperature threshold; calculating the brake drum temperature of the tested vehicle after each preset distance interval, then calculating the safety speed of the testedvehicle through the follow-up road section according to the preset temperature threshold value, and enabling the tested vehicle to safely and efficiently pass the continuous downhill road section.

The invention belongs to the technical field of brake materials, and particularly relates to a friction material, a carbon ceramic brake pad formed through preparing of the friction material, and a preparing method of the carbon ceramic brake pad. The friction material comprises, by weight, 8-16 parts of carbon ceramic fiber, 1-6 parts of steel fiber, 3-12 parts of mineral fiber, 8-16 parts of chemigum modified phenolic resin, 5-11 parts of powder chemigum, 4-11 parts of petroleum coke, 9-22 parts of barium sulfate, 1-5 parts of polyacrylonitrile fiber, 6-16 parts of heavy magnesium oxide, 4-12 parts of kaolin and 2-8 parts of silicon dioxide. The above raw materials are mixed to form the mixture and placed into a die to be pressed and cured into a blank, the blank is heated and cured, andthe carbon ceramic brake pad is obtained. The brake pad has the beneficial effects of being small in abrasion thickness and long in service life; the tolerable temperature of the friction material ishigh, the problem of brake failures caused by the high brake pad temperature during frequent braking is solved, and the driving safety is ensured.

The invention relates to the technical field of container front cranes, in particular to a hydraulic braking system of a container front crane. The hydraulic braking system is provided with a vehicle body, wherein a left pedal plate valve, a right pedal plate valve, a liquid charging valve, energy accumulators, a front-axle brake and a rear-axle brake are arranged on the vehicle body. The hydraulic braking system is characterized in that: the right pedal plate valve is formed by connecting a front-axle braking oil-way and a rear-axle braking oil-way in parallel; a slow-action valve is arranged on the left pedal plate valve; a valve core of the slow-action valve is connected with a valve core of a braking valve in series; the upper end of the valve core of the slow-action valve is connected with pedals; an oil inlet of the slow-action valve is communicated with a variable control port of a variable pump; an oil return port of the slow-action valve is communicated with an oil storage tank; when the left pedal plate valve is pedaled, oil at a braking port of the left pedal plate valve is communicated to a hydraulic control port of the right pedal plate valve, equivalently, the left pedal plate valve has a power cutoff effect at the same time of pedaling the right pedal plate valve. An oil outlet of the liquid charging valve is respectively connected with the energy accumulators of a parking braking valve, the left pedal plate valve and the right pedal plate valve, and the parking braking valve is integrated on the liquid charging valve. The hydraulic braking system disclosed by the invention has the advantages of novel structure, high safety, braking stability and the like.

The invention relates to a spiral ventilation radiating brake drum which comprises a brake drum body. A brake friction face is arranged in the middle of the brake drum body, 4-10 rows of radiating holes series evenly distributed spirally are formed in the brake friction face, each row of radiating hole series comprises 4-8 radiating holes, and each row of radiating hole series are arranged linearly in the cross section of the brake drum body. The brake drum is light in weight, reduces the steps in the radiating process aspect of the existing brake drum, reduces production cost and greatly improves the braking capability foremost.

The invention discloses a service brake system for a wheel loader. The system comprises an air compressor, an unloading valve, an air cylinder and a safety valve. The air compressor is connected withthe air cylinder through the unloading valve; the safety valve is arranged on the air cylinder and is used for limiting the highest pressure of the system. The service brake system is characterized byfurther comprising an air brake valve, a relay valve, a brake air chamber and a brake, an outlet of the air cylinder is connected with an air inlet of the air brake valve and an air inlet of the relay valve, an air outlet of the air brake valve is connected with a control air pressure input port of the relay valve, and an air outlet of the relay valve is connected with the brake through the brakeair chamber. The system cancels the brake fluid to thoroughly solve a gasification problem of the brake fluid and improve the safety of the service brake system. The relay valve is used in the system, the position is reasonably arranged, the inflation time of a brake air chamber is shortened, the brake lag time is shortened, and brake is more sensitive.

The invention provides application of an electric pneumatic braking rapid air charging device with an air pressure supplement function, and relates to the technical field of application of carriage braking release. The application of the electric pneumatic braking rapid air charging device with the air pressure supplement function is characterized in that a locomotive supplies air to carriages; a control cable transmits a release instruction electric signal to an electric pneumatic distribution valve through a secondary control branch A, the electric pneumatic distribution valve obtains the release instruction electric signal to work, a release air pipe is connected to a braking branch pipe, and a release air cylinder conducts air charging on a braking main pipe through the release air pipe, the electric pneumatic distribution valve and the braking branch pipe; when the electric pneumatic distribution valve has a sense that the pressure of the braking main pipe is increased, and has obtained the release instruction electric signal from the secondary control branch A, a braking cylinder pipe is connected to the atmosphere; a, phase release of train braking is conducted, and b, direct release of train braking is conducted; and air charging is conducted, wherein air charging begins when train braking is released, in the process that an air compressor which conducts stable pressure output conducts air charging on the braking main pipe, when a serial control device enters the pressure maintaining position, air charging temporarily stops, and when the serial control device is located at the release position all the time, air charging is conducted to enable the constant pressure of the braking main pipe to be achieved.

The invention discloses a vehicle brake-by-wire system overheating protection control method and system and a storage medium. The method comprises the steps: obtaining the vehicle speed and pedal displacement information; when it is detected that the vehicle speed and the pedal displacement information meet the thermal protection starting condition, sending an overheating protection instruction to a vehicle brake-by-wire system; and according to the received overheating protection instruction, controlling an electronic parking actuator to conduct parking braking on the vehicle, and controlling an electronic booster to reduce the output torque. After braking force is applied through the electronic parking actuator, the output torque and power of the electronic booster can be greatly reduced, and braking failure caused by overheating of the electronic booster can be remarkably avoided.

The invention discloses a normally-locked hydraulic disc brake device which comprises main clamp body, adjusting screw plug, limit screw, piston, limit location step, first sealing ring, second sealing ring, spring, third sealing ring, fourth sealing ring and positioning screw, step guiding hole and threaded hole are arranged in the main clamp body, adjusting screw plug is connected at bottom of the main clamp body through the threaded hole, adjusting gasket is arranged between the adjusting screw plug and the main clamp body, piston is pressed into the step guiding hole through matching, limit screw is connected at bottom of the adjusting screw plug through threads, spring is arranged in step guiding hole of the large shaft end, the piston is provided with first groove and second groove outside the large shaft end, first sealing ring and second sealing ring are respectively arranged in the first groove and the second groove, the piston is provided with third groove and fourth groove outside the small shaft end, and third sealing ring and fourth sealing ring are respectively arranged in the third groove and the fourth groove. The overall structure design of the invention is ingenious and convenient to use.

The invention discloses a safety protection device suitable for belt transmission. The device comprises a fixed plate, wherein an electromagnet I, a large belt wheel, a torque sensor, a motor and a PLC (Programmable Logic Controller) are arranged on the fixed plate, a small belt wheel on an output shaft of the motor is connected with the large belt wheel through a belt, and the torque sensor is also arranged on an output shaft of the motor. The invention further discloses a control method of the safety protection device suitable for belt transmission. When accidents such as power failure, beltbreakage and the like happen, by controlling the on-off of the current of the electromagnet, the electromagnet locks a driven belt wheel, so braking of a driven part mechanism is realized, and a problem that when the power is suddenly cut off or a belt is broken, if a load exists on the driven side and a corresponding safety protection device does not exist, safety accidents are possibly caused is solved.