197results about How to "Avoid injury accidents" patented technology

The invention relates to an online detection electric-loading test bed for a car hand-gear gearbox and an operating method thereof. The test bed comprises a test bed main body and a motor case body, an electric driving control system, a computer measurement and control system, and an oil supply system, and is characterized in that a clutch unit is connected behind a torque revolution speed transducer of the test bed, a tray sliding table is arranged under a tested gearbox, and the tested gearbox has a structure with two output shafts. The test bed and the operating method thereof have the following advantages: conductively closed power feedback loading is adopted for saving energy sources; an input shaft driving motor and an output shaft driving motor of the tested gearbox on the test bed are the power input and the power output of each other; and under the state of seamless smooth conversion electric driving and regenerative power generation, the four-quadrant work is realized; a structure that motors are separated from a machine tool main body is adopted, and the motors are arranged in an independent case body; the test bed is applicable to the tests of various models of hand-operated and automatic gearboxes; an industrial control computer system and a measurement and control instrument are adopted to realize the automatic control for test procedures; the test bed has perfect interlocking protection function; and a quantitative oil feeding and discharging system is adopted.

The invention relates to a double-layer or multi-layer scalable foot-miss prevention plate mechanism for removing clearance between a rail transit carriage and a platform. The foot-miss prevention plates are overlaid and can move mutually. When a train arrives and stops stably, the foot-miss prevention plates are pushed forward until touching an outer casing of the carriage. When train doors are closed, the foot-miss prevention plates are withdrawn backward totally. The invention has the advantages of simple structure, low cost, easy maintenance and long service life and can totally put an end to passenger hurt accidents caused by the clearance between the carriages and the platform.

The invention relates to a control method and system for elevator safety operation. The control method comprises the following steps of: obtaining a depth image inside an elevator car; obtaining a target depth value of an identified object in the depth image when image information of the identified object exists in the depth image; and sending prompting information of leaving an elevator when the target depth value is smaller than a preset depth threshold value. According to the scheme adopted by the invention, the depth image inside the elevator car is identified, analyzed and processed, so that the target depth value of the identified object inside the elevator car can be obtained; when the target depth value is smaller than the preset depth threshold value, the identified object is indicated to be not suitable for taking the elevator, and promoting information of leaving the elevator can be sent to prompt the identified object to leave the elevator, so that occurrence of an injury accident possibly due to the fact that the identified object is not suitable for individually taking the elevator is avoided, and safety of elevator operation is improved.

The invention relates to a screw mounting device which comprises a bracket body (1), wherein the lower part of the bracket body is provided with a worktable (2); the upper part of the bracket body is provided with a plurality of rail slots (3); one side of the rail slots (3) is provided with a screw gun (4); a laser sensor (31) is arranged on the rail slots; and the screw gun is provided with a photosensitive plate (41) matched with the laser sensor. The invention is provided with a mistaken impact prevention mechanism; and before mounting the screw, the laser sensor can allow the screw gun to be electrified only after sensing that the screw gun has been adjusted to the designated position, thereby preventing personnel injury accidents caused by misoperation in the screw gun adjustment process.

The invention discloses a visual intercom indoor terminal with a security and protection function. The visual intercom indoor terminal comprises a microprocessor, a security monitoring module and a smoke detection circuit, wherein the microprocessor is connected with a visual intercom module, the security monitoring module, an emergency power supply automatic switching module, an emergency evacuation module and a communication interface respectively, the security monitoring module comprises the smoke detection circuit, a temperature detection circuit and a fuel gas leakage detection circuit, the smoke detection circuit comprises a detection passage circuit and a reference passage circuit which are respectively connected into two input ends of a differential amplification circuit I, and the output end of the differential amplification circuit I is connected with a threshold comparing circuit I in series. The visual intercom indoor terminal has the beneficial effects that on one hand, danger situations can be accurately and quickly forecast by utilizing a multi-sensor fusion technology, and on the other hand, the visual intercom indoor terminal is arranged at vantage positions close to gates or passages, when accidents happen, emergency switches are automatically switched, and trapped personnel can be emergently guided and evacuated, so that great property loss and personnel injury accidents are prevented from occurring.

The invention discloses a silage feed fine strip kneading machine. The silage feed fine strip kneading machine comprises a machine frame, wherein a conveying device, a feeding device, a crushing device and a power device are arranged on the machine frame; an outlet of the conveying device is connected with an inlet of the feeding device; an outlet of the feeding device is connected with an inlet of the crushing device; the crushing device comprises a crushing supporting frame which is fixed to the machine frame; a main shaft is mounted on the crushing supporting frame; a crushing chamber is arranged under the main shaft; a plurality of toothed plates are fixed to the bottom of the crushing chamber; a plurality of rotor web plates are axially mounted on the main shaft; each of pin shafts isarranged in each rotor web plate; and a plurality of hammer pieces are mounted on each pin shaft in a sleeving manner. According to the silage feed fine strip kneading machine disclosed by the invention, forage is automatically transported to the feeding device through the conveying device; after treatments of extruding, flattening and the like are performed on the forage by the feeding device, the forage is further transported to the crushing device by the feeding device to be subjected to treatments of kneading, crushing and the like, and the kneading effect of the forage is greatly improved; and the forage can be crushed into the fine strip-shaped forage of which the length is 100-250mm, and the fine strip-shaped forage is directly subjected to silage to be eaten by livestock.

A paper cutter with cutting knife moving vertically is composed of support frame consisting of vertical piles and top beams, air-cushion bench, paper pusher with more vacuum sucking disks, motor-leading screw drive mechanism, knife holder, and knife. Said knife is linked to a electric hydraulic cylinder mounted to top beam for moving up and down. Its advantages are high cutting precision and high safety.

The invention relates to a driving auxiliary calibration detection system, which is characterized in that an industrial computer is connected with an automobile CAN bus through a CAN module; a PLC isconnected with the industrial computer; a servo driver is connected with the PLC (programmable logic controller); a transmission mechanism is connected with the servo driver; a centering mechanism isarranged at a vehicle calibration station and is connected with a transmission mechanism; a V-shaped groove is formed in the vehicle calibration station; a calibration block is arranged in the vehiclecalibration station and is connected with the transmission mechanism; the vehicle calibration station is installed. A machine is used for replacing labor; the calibration time is greatly shortened; through the V-shaped grooves and the centering mechanism, the positioning accuracy of the vehicle is ensured; 360, LDW (lane departure warning) and FCW (forward collision warning) are completed on onecalibration table; after the calibration is completed, the calibration result is printed and stored into a database; the repair and the checking are convenient; a wrong entering detection function isset; when people enter the system by mistake in the calibration process, all mechanisms immediately stop; the occurrence of personnel injury accidents is avoided.

The invention discloses a silage rubbing filament machine, which comprises a rack, a conveying device, a feeding and cutting device, a pulverizing device and a power device. The feeding and cutting device comprises a grass feeding roller upper roller assembly, a grass feeding roller lower roller assembly and a cutting assembly. The grass feeding roller upper roller assembly comprises an upper roller movable support, an upper roller bearing seat and a grass feeding roller upper roller. Since the upper roller movable support is movably mounted on a feeding mechanism rack, the distance between the grass feeding roller upper roller and a grass feeding roller lower roller can be adjusted up and down according to the amount of forage, which avoids the phenomenon of accumulation and jamming during the conveying process. At the same time, a moving blade in the cutting assembly realizes the up and down reciprocating motion under the action of an eccentric wheel and a connecting rod, and the moving blade and a fixed blade are engaged to cut the forage cut into desired short sections before entering the pulverizing device, which can greatly improve the rubbing effect of the forage. In addition, the length of the cut forage can be adjusted by adjusting the rotation speed of a cutting shaft, and the cut forage can be processed into the required short filament forage by the pulverizing device and directly stored for feeding the livestock after silaging.

The invention discloses a thermoelectrically separated type PCB member and a processing method thereof. The PCB member comprises a metal substrate; depth-controlling etching is carried out on the middle part of the metal substrate to form a boss bonding pad and a PP layer is arranged around the metal substrate; and a circuit layer is arranged on the PP layer and is formed by etching of a metal foil layer laminated on the PP layer and the boss bonding pad. In addition, the preparation method includes: S1, a metal substrate is made to form an inner pattern and etching is carried out on the substrate to form a salient point bonding pad; S2, a PP layer and a metal foil are excavated; S3, the metal substrate with the salient point bonding pad etched, the PP layer, and the metal foil are laminated to form a half-finished laminated multi-layer board product; S4, mechanical grinding is carried out to grind the salient point bonding pad to expose the salient point bonding pad; and S5, the circuit is etched. The method aims at realizing processing of a thermoelectrically separated type PCB member. According to the thermoelectrically separated type PCB member, components are connected with the copper substrate directly to realize a direct cooling effect, so that the heat dissipation effect is improved substantially, the light output rate of the LED is enhanced, and the high stability of the lighting effect is guaranteed.

The present invention provides a kind of car that prevents children from accidentally locking or forgetting to cause injury accidents in the car, including a car body, an infrared sensor, a sound sensor, an image collector, and a controller; the infrared sensor, the sound sensor, and the image collector are all It is connected with the controller through the analog-to-digital conversion module; the controller can also be connected with the car ECU controller in the car body, and also includes an alarm device connected with the controller, and a display connected with the controller; it also includes a connection with the controller The SIM communication module, the handheld terminal connected to the SIM communication module through 2G / 3G / 4G network; when the car is in use, it can automatically monitor whether there are people in the car when the car is locked, and automatically send out an alarm message , to remind passers-by to pay attention, and to send reminder information to car owners to remind car owners to pay attention. At the same time, this design can also realize the function of opening the door in the car, so as to avoid the phenomenon of people being locked in the car and causing injury accidents. .

The invention provides a brand-new intelligent air cylinder mounting and dismounting device which comprises a control system, a running system, a lifting system, a power air cylinder clamping system and an air cylinder positioning system, wherein an electric cabinet in the control system is connected with a PLC (programmable logic controller); the PLC receives signals of an encoder in the running system and a photoelectric sensor in the air cylinder clamping system; the signals are transmitted to the electric cabinet and converted into electric signals; the electric cabinet controls a start or stop command of a driving motor, an electric hoist, a positioning driving motor and an electromagnetic pneumatic valve; and a mounting or dismounting process of an air cylinder can be accomplished automatically by pressing down a mode button of a remote controller according to an actual condition. Multiple actions in a cycle only require once command of field personnel; a working cycle is accomplished within 3min in a slow state; and a working cycle is accomplished within 2min in a fast state. The device is high in efficiency, safe in mounting and dismounting process, low in labor cost and simple in structure, and raw materials are easy to obtain and manufacture.

The invention provides a righting type downhole cable protector, which is provided with a tubular body, wherein the inner side surface of the tubular body protrudes outwardly along the radial direction to form an internal cable groove, a plurality of righting rib plates are evenly distributed on the outer side surface of the tubular body along the circumferential direction, the righting rib plates are arranged along the radial direction of the tubular body, the inner end of each righting rib plate is connected with the outer side surface of the tubular body, the outer end of each righting rib plate is connected with a drag reduction roller, and the inner side surface of the tubular body is provided with a rubber cushion layer on the part except the internal cable groove. The righting type downhole cable protector can be used for righting an oil pipe column effectively, and reduces the frictional resistance between the protector and the inner wall of a casing pipe, thereby ensuring effective protection of the downhole cable, and prevents the occurrence of downhole accidents such as the cable is cut off by clamping and pulled off.

The invention relates to quick arc-shaped raised-edge drill rod dismounting device and method. The quick arc-shaped raised-edge drill rod dismounting device comprises a three-edge shaft and a trigonal shaft, wherein the three-edge shaft is divided into a cylinder section, a limit disc, a prism section and an external thread section, the cylinder section is used for being connected with a drilling machine chuck so as to perform circumferential rotation or axial movement along with the drilling machine chuck, and the external thread section is used for being connected with an arc-shaped raised-edge drill rod; and the section shape and size of the prism section are identical with those of the arc-shaped raised-edge drill rod. The dismounting method of the device comprises the following steps of: after the drilling construction is completed, installing the three-edge shaft and the trigonal shaft on a drilling machine power head chuck, pushing the power head chuck to a drill rod position, forwarding the chuck so as to enable the three-edge shaft and the drill rod to be connected and not to be screwed up tightly, dragging the drill rod to the drill rod position, sliding the trigonal shaft to be sheathed at the position at which the three-edge axis and the drill rod are connected, clamping a drilling machine holder, reversing the drilling machine chuck, opening the connection between the first drill rod and the second drill rod, manually reversing and taking down the first drill rod, and repeating the steps until all the drill rods are dismounted. The device can be used for greatly reducing the safety dismounting danger while improving the drill rod dismounting efficiency.

The invention discloses a hydraulic damper sealing double-medium detection apparatus and a detection method thereof. The hydraulic damper sealing double-medium detection apparatus comprises an apparatus main body and further comprises a work module arranged inside the apparatus main body, and the work module comprises a hydraulic detection unit, an air pressure detection unit, a vacuum-pumping unit and a reversing valve; and the top portion of the apparatus main body is also provided with a detection work platform, a hydraulic damper is fixedly placed on the detection work platform, the work module is connected with an inner cavity of the hydraulic damper through the reversing valve, and by use of motion of the reversing valve, the hydraulic detection unit, the vacuum-damping unit or the air pressure detection unit can be respectively controlled to act on the hydraulic damper so that sealing performance of the hydraulic damper can be detected through a liquid medium and a gas medium. According to the invention, the accuracy of a detection result is guaranteed, the detection steps are simple and convenient, the detection time is shortened, and the detection efficiency is improved.

A connecting rod seat automatic loading and welding device used for electric resistance welding solves the problems of manual feed and manual penetration into a core shaft which are required during the resistance welding of the connecting rod seat. The device comprises a core shaft penetration mechanism and a connecting rod seat ordering and feeding mechanism, the connecting rod seat ordering and feeding mechanism is positioned on a mounting seat and comprises a connecting rod seat conveying passage, a connecting rod seat conveying air cylinder and a feed limiting plate, the connecting rod seat conveying passage comprises an inclined passage connected with a horizontal passage, the connecting rod seat conveying air cylinder is positioned at the front part of the horizontal passage, a connecting rod seat conveying cylinder rod extends into the horizontal passage from the top down, the feed limiting plate is positioned at the end part of the horizontal passage, and a to-be-weld connecting rod seat conveying position is positioned between the feed limiting plate and the connecting rod seat conveying cylinder rod. According to the invention, the actions of the air cylinder and relevant components are used for replacing the operations of backward manual feeding and manual core shaft penetration, the labor intensity of workers is alleviated greatly while the production efficiency is improved, personnel injuries and accidents are avoided, and the welding quality is enabled to be ensured.

The present invention relates to a water tank in automobile cooling system, particularly a automobile water tank cover intelligent locking apparatus, which includes a water tank and a water tank cover, wherein the cylinder on lower end of the water tank cover is provided with screw thread part, and the screw thread part fits with the screw thread part on opening of the water tank, characterized in that the cylinder on the lower end of the water tank cover is provided with a bolt hole, the water tank corresponding to the bolt hole is provided with a bolt, the bole controlled by a electric machine moves forward or backward; the electric machine is controlled by a control unit and the control unit connects with the automobile engine and the temperature detector in the water tank respectively. The invention mainly solves technical problem that existing automobile water tank safety cover in the water tank can be opened when in high temperature or the automobile is still running, and a display apparatus can help to remind people of the high temperature environment inside the water tank to ensure security.

One embodiment of the invention discloses a well lid capable of monitoring the state of a well. The well lid comprises a liquid level monitoring module, a well lid state monitoring module, a main control module, a wireless communication module and a well lid body; the liquid level monitoring module is used for monitoring the liquid level height of a well and generating liquid level information; the well lid state monitoring module is used for monitoring the state of a well lid and generating well lid state information; the main control module is used for receiving the liquid level informationand the well lid state information; and the wireless communication module sends the liquid level information and the well lid state information to a server. According to the well lid, the liquid levelheight and the well lid state of an underground pipeline such as a rain sewage well can be monitored in real time, remote alarming is conducted in time when problems occur, then a municipal administration department can handle the problems in time, and damage accidents caused by abnormality of the well lid can be avoided.

The invention relates to a device for picking fruits on high branches through sleeving and cutting. The device comprises a high fruit picking rod, a sleeve type picking head and a soft body fruit guiding bag, wherein an orifice swinging device, a fruit body positioning device and a remote controlled fruit cutter are arranged between the high fruit picking rod and the sleeve type picking head; the orifice swinging device comprises an elastic shaft seat, a rope pulling coiling block and a swing pulling rope; the fruit body positioning device comprises a fruit body air sac, a control air sac and an extruding air conveying plate; the remote controlled fruit cutter comprises an orifice fruit picking cutter, a fruit cutting handle and fruit cutting pulling ropes; the orifice fruit picking cutter comprises two zigzag cutter bodies; the fruit cutting pulling ropes are connected between the zigzag cutter bodies and the fruit cutting handle. According to the embodiment of the invention, various obliquely hanged fruits can be picked conveniently through the orifice swinging device; the fruit body positioning device adjusts fruits to the optimum positions and picks the fruits; the remote controlled fruit cutter is arranged, so that fruit growers stand on the ground to cut fruit spurs conveniently, and the soft body fruit guiding bag automatically puts the fruits in a basket or other fruit holding apparatuses. Therefore, the device is reasonable in structure and convenient to use.

The invention provides an anti-blowout control valve. A lower locating seat is arranged at the lower part of the inner cavity of a valve body; a ball valve is arranged on the lower locating seat; an upper locating seat is arranged above the ball valve; the lower end of the upper locating seat is located on an inner shoulder of the valve body; a pressing cap is connected with the upper part of thevalve body and used for pressing the upper locating seat; a locating seat sealing ring is arranged between the upper locating seat and the valve body; an anti-blowout sealing ring is arranged betweenthe upper locating seat and the ball valve; a faucet is arranged on the side face of the valve body; the front end of the faucet is inserted into the ball valve; a faucet sealing ring is arranged between the faucet and the valve body; an inner through hole is formed on the ball valve; and an inner shoulder is arranged at the lower part of the valve body. If blowout exists, a suspension connector is arranged at the upper part of an oil pumping rod; the suspension connector is arranged on the inner shoulder at the lower part of the valve body, and a rod piece above the suspension connector is taken away; the faucet is rotated to make the ball valve rotate 90 degrees, so the inner through hole 10 on the ball valve is closed; therefore, the anti-blowout control valve prevents the blowout, avoids personnel injury accidents and crude oil loss and environmental pollution, and brings outstanding economic benefit and social benefit.

An anti-collision alarm device for a shopping cart according to the present invention comprises a vehicle frame, an anti-collision module, a power supply module and an alarm module are arranged on the vehicle frame, the anti-collision module includes an arc-shaped anti-collision plate, and the anti-collision plate Located at the front end of the shopping cart, an anti-collision spring is clamped between the anti-collision plate and the shopping cart; the alarm module includes a first induction switch, a second induction switch and an alarm; the anti-collision plate A first connecting rod is provided between one end and the first induction switch, a second connecting rod is provided between the other end of the anti-collision plate and the second induction switch, and the first induction switch and the The second induction switch is electrically connected to the alarm respectively; its anti-collision module is retractable, and when it hits a person or an object, the anti-collision module retracts to reduce the impact force, prevent collision accidents, and alarm The module will emit an alarm sound to remind the pusher and the hit person to pay attention to avoiding.

The invention relates to a method for assembling a large-area safety net. The method comprises the following steps: 1) building a row of floor type cross scaffolds in the center of an assembly hall; 2) assembling a steel wire rope and a counterweight, wherein one end of the steel wire rope is fixed with a central scaffold pole through a U-shaped buckle, while the other end is towed to the outside of a main body structure through a small hoist to drop to the ground, and the tail end suspends the cement counterweight; 3) sleeving a side rope of the safety net on the stretched steel wire rope by using a safety clasp; 4) binding a hemp rope at the upper end of the side rope of the safety net, and towing the upper end of the safety net to the central scaffold pole by a hemp rope through a fixed pulley; 5) binding and fixing the hemp rope with the central scaffold after the safety net is in place; and 6) binding and fixing the side rope between adjacent net pieces with the steel wire rope in the center from the top to bottom. Compared with the prior art, the method has the advantages of solving the problems of stretching and suspending the safety net under the condition of not building the scaffold and the like.

The invention discloses a software closed appliance gas leakage alarm device on the basis of a gas pressure sensor and a strain gauge and relates to a signal device which takes effects by the pressure of an inflatable object. The software closed appliance gas leakage alarm device comprises a gas leakage signal sending device, a gas leakage signal receiving device, an alarm device and a power supply system, wherein the gas leakage signal sending device mainly comprises the gas pressure sensor, a strain gauge device, a sent signal conditioning circuit, a sending device singlechip and a wireless data sender; the gas leakage signal receiving device mainly comprises a wireless data receiver, a received signal conditioning circuit, a receiving device signalchip, a keyboard and a liquid crystal display; the alarm device comprises an LED (Light-Emitting Diode) lamp and a buzzer; the power supply system mainly comprises a rechargeable battery and a solar cell panel. The device disclosed by the invention automatically gives an alarm when a software closed appliance has the phenomenon of gas leakage or is seriously deformed, solves the problem of incapacity of timely giving an alarm when an existing software closed appliance has the phenomenon of gas leakage or is seriously deformed, and overcomes the defect that in the prior art, an existing gas leakage alarm device can be only used in gas leakage alarm of a tire and has a narrow application range.

The invention discloses a control device for last strength in javelin throwing teaching. The control device comprises a vertical pillar A and a vertical pillar B, wherein the vertical pillar A and the vertical pillar B are fixedly arranged in a spaced mode and are different in height; the vertical pillar A is higher than the vertical pillar B by a certain size; a javelin guide steel rope is connected between the upper part of the vertical pillar A and the upper part of the vertical pillar B, and an exercise javelin is arranged on the javelin guide steel rope in a length direction in a sliding mode; and a height-angle regulating device, which is used for regulating the exercise javelin, is arranged on the vertical pillar A and the vertical pillar B. The control device disclosed by the invention has the technical characteristics and advantages that by virtue of the control device, students, in an exercise process, can master the last strength and throw the javelin by an appropriate angle; and through repeated training, a good muscle power exertion feeling can be established, so that stable dynamic finalization is formed, and the technical problem of old imitation which, through bare-handed exercise, is inconvenient to master transition of javelin running-up and last strength is solved.

The invention discloses an electromagnetic induction heating vacuum cup coaster. The electromagnetic induction heating vacuum cup coaster comprises a coaster body (1) and a coil (2) fixed on the coaster body and is characterized in that an output end of a medium-frequency power supply (3) is connected to two ends of the coil (2) through a switch K. The electromagnetic induction heating vacuum cup coaster has the advantages as follows: beverage is heated by the aid of a spoon in a cup, the injury accident caused by overhigh temperature of the cup due to heat conduction is avoided, and energy loss caused by low heat conductivity of materials is avoided.

The invention discloses an under-voltage protection circuit of a battery pack. The under-voltage protection circuit comprises a main board control system, a battery management system and a battery pack. The battery pack is a battery array formed by series connection of a preset number of battery groups. The battery management system is used for detecting the voltages of each battery group according a preset period; and when the voltage of the battery group is lower than or equal to a preset over-discharging protection voltage, the output of the battery pack is turned off. The main board control system is used for obtaining a lowest voltage in the preset number of battery groups from the battery management system; and when the lowest voltage is lower than or equal to a preset under-voltage protection voltage, the main board control system is turned off in a soft stop manner. The preset under-voltage protection voltage is lower than the preset over-discharging protection voltage. According to the under-voltage protection circuit, the stored energy of the battery pack can be utilized fully and the under-voltage protection function of the main board control system is superior to the battery management system, so that any injury accident caused by sudden outage of the battery management system can be avoided.

The invention relates to the technical field of a ground wire device in power system transformer substation, in particular to a ground wire automatic monitoring device, which comprises a central processing unit (CPU), a line communication module, an output relay, a warning lamp relay, a voice module, a first coupler, a second coupler, a loudspeaker, a net gate switch and a grounding terminal switch for ground wire signal collection, wherein the grounding terminal switch consists of a bolt, a spring, two nylon sleeves, a fixing electrode and a movable electrode; the fixing electrode and the movable electrode are provided with signal wire wiring holes; the end of the bolt for sheathing the movable electrode is meshed with a nut; and the nylon sleeve forms a concave shape to perform the insulation function. The fixing electrode and the movable electrode are in the shape of a groove for meshing with the nylon sleeves. When the ground wire is put on the movable electrode, the spring is pressed to make the movable electrode in contact with the fixing electrode, and the electrical signal is conducted. After the ground wire is disassembled, the movable electrode and the fixing electrode are separated and the electrical signal is disconnected, thus the functions of electrical signal outputting after the ground wire is connected and electrical signal disappearance after the ground wire is disassembled is achieved. The invention can prevent the accident caused by switching on with ground wire.