36results about How to "Reduce the chance of danger" patented technology

The invention belongs to the field of lifting equipment, and in particular relates to a pivot fixed multi-face constrained scissor-type lifting mechanism. Three groups of scissor-type trusses are vertical to a base; the bottom ends of the three groups of scissor-type trusses are connected with three epsilon-type connecting pieces which are fixed on the base in a regular triangle manner respectively so as to form rotation pairs, and the top ends of the three groups of scissor-type trusses are connected with three epsilon-type connecting pieces which are fixed on the lower plane of a supportingplatform in the regular triangle manner respectively so as to form rotation pairs; the three groups of scissor-type trusses are in regularly triangular prism arrangement between the supporting platform and the base; an angle between the plane on which each group of scissor-type truss is placed and the plane on which the adjacent scissor-type truss is placed is 60 degrees; among the three groups of scissor-type trusses, central hinging points of crossed connecting rods of scissor layers are connected with the corresponding peaks of the regularly triangular connecting pieces so as to form rotation pairs; and a driving device supports the regularly triangular connecting piece of the first scissor layer on the base so as to drive the whole lifting mechanism to lift. The pivot fixed multi-faceconstrained scissor-type lifting mechanism has a stable structure and high rigidity, and is applicable to environments having requirements such as large loading capacity, working height and the like which cannot be met by general lifting equipment.

The invention belongs to the field of lifting equipment, and in particular relates to a fulcrum fixed multi-surface over-constrained radial scissor type lifting mechanism. W-shaped connecting pieces are respectively fixed on the upper plane of a base and the lower surface of a bearing platform according to vertex positions of regular triangles; three groups of scissor type trusses are vertical to the base; the bottom ends and the top ends of the scissor type trusses are connected with the W-shaped connecting pieces through a bottom rotation pair respectively; an inclined angle of 120 DEG is formed by planes where every two groups of scissor type trusses are positioned; star-shaped connecting pieces are arranged among the three groups of scissor type trusses and among connecting rods with the same height on each layer; and a driving device is arranged at the central position of the base. Compared with a parallel type scissoring machine in the prior art, the invention has the advantages that: the mechanism has a stable structure, the weight of the mechanism can be reduced without the variation of intensity, the rigidity is improved, and high loads can be born, so that the maximum operation height of a lifting platform is increased; and the mechanism has the characteristics of high foldable ratio, compact structure, low dead weight, high bearing capacity, high throughput capacity and high operability.

The invention provides a head-up display device, a driving method, a vehicle and an electronic device. The head-up display device includes a display assembly, a control unit and an execution unit, wherein the display assembly is used to output a display image; the control unit is used to acquire a real-time vehicle speed of the vehicle and generate an image distance control signal according to thereal-time vehicle speed of the vehicle; the execution unit is connected to the display assembly for adjusting the display assembly according to the image distance control signal and controlling the image distance of the image displayed by the display assembly to change according to the change of the real-time vehicle speed; the control unit is further used to generate an angle control signal according to the real-time vehicle speed of the vehicle; and the execution unit is further used to drive the display assembly according to the angle control signal and adjust a top view angle of the imagedisplayed by the display assembly. The technical solution of the head-up display device can reduce the switching time between the normal driving and watching of the image displayed by the head-up display device for the driver, thus reducing the probability of occurrence of danger.

The invention provides an insulating hanging rack and a telescopic clamp for electrified connection and an operation method. The insulating hanging rack comprises a top end hanging seat, a lower end clamping seat, a hanging arm, a hanging arm fixing frame, a fixed clamp, a movable clamp, a locking switch, an outer sleeve, an inner pipe, a spring clamping sleeve and a pressure spring. The insulating hanging rack can be hung on large and small cross arm angle steel of two specifications, so that an operator keeps a certain distance from an electrified body. The insulating hanging rack is made ofinsulating materials, which provides safety guarantee for high-altitude live working. The telescopic clamp comprises a melon head, an outer pipe, an inner pipe, an inner pipe stretching grip, an outer pipe grip, an extrusion sliding block, a telescopic rod, a hanging seat, a pressure spring clamping sleeve, a pressure spring, a jackscrew and a steel ball. The telescopic clamp can be used for clamping and locking tools with different section shapes, is mainly used for transferring tools or cables to aloft work personnel by workers on the ground, is simple to operate, convenient to carry and firm in clamping, protects the tools, and is suitable for narrow areas where a lift truck cannot enter and being used with the insulating hanging rack.

The invention provides an intelligent driving training device, system and method, and belongs to the technical field of intelligent traffic training; the utility model can solve the problem that the existing users have poor training effect or high risk coefficient during driving training. The intelligent traffic training device is characterized by comprising a road condition identification modulefor acquiring and identifying current road condition information of the road on which the user is running; a roadblock setting module for identifying current road condition information identified byidentification module according to the road condition, and a pre-stored road condition adjustment mode to set a virtual roadblock in the current road condition; a driving state identification module for identifying a driving state of a vehicle drived by a user in a current road condition provided with the virtual roadblock; and a prompt module for sending prompt information to the user according to the driving state of the vehicle driven by the user identified by the driving state identification module.

The invention belongs to the technical field of medical equipment, and discloses an intelligent orthopedic surgery system. The intelligent orthopedic surgery system is provided with a preoperative detection module, an intra-operative intelligent control module, an intra-operative intelligent operation module, an intra-operative detection module and a postoperative conditioning solution module. Thepreoperative detection module, the intra-operative intelligent control module, the intra-operative intelligent operation module, the intra-operative detection module, and the postoperative conditioning solution module are sequentially executed, and the intra-operative intelligent control module and the intra-operative intelligent operation module are the same level programs. The required operative procedure is input by the intra-operative intelligent control module, and the surgical operation is performed by the intra-operative intelligent operation module. The surgical progress and the change of a surgical trauma along the operation are monitored by the intra-operative monitoring module to control the surgical trauma during the operation, and after the operation is completed, the postoperative conditioning solution module provides a suitable and accurate postoperative conditioning solution. The intelligent orthopedic surgery system has concise steps, the surgical trauma can be controlled after the operation is completed and the trauma is greatly reduced, and the adapted surgical conditioning solution can be given in time.

The invention discloses a reinforced fracture-resistant road-bridge pavement slab which comprises a first pavement slab and a second pavement slab. A second steel plate is mounted at the top end of each of the first pavement slab and the second pavement slab, a first concave block, a second concave block and a first inserting plate penetrate two sides of a second inserting plate, the bottom ends of two sides of a first steel plate are connected with the first pavement slab and the second pavement slab, a screw penetrates the first steel plate and the second inserting plate, a bearing is fixedon the front of a first fixing block through a rotating rod, a supporting rod is mounted at the left end of the bearing, a convex block is mounted on the left side of the top end of the supporting rod, and the outer wall of the convex block is connected with a third concave block. Through cooperation of the first concave block and the second concave block, the supporting rod clockwise rotates through the bearing to be buckled with the third concave block to mount a tension spring on the surface of the supporting rod to the end of the second inserting plate, so that probability of danger is lowered, and traffic accidents caused by fracture of the pavement slab are reduced effectively.

The invention discloses a teaching system and a teaching method based on an AR system, and belongs to the technical field of augmented reality; the teaching system based on the AR system comprises thefollowing components: a simulation module that is used for automatically selecting a corresponding simulation scene according to the accessed simulation equipment; a motion capture module that is used for capturing trainee motions, and calculating the position of the body of the trainee relative to the simulation equipment; a display module that is used for displaying a corresponding picture according to the simulation scene and displaying the corresponding picture according to the motion of the trainee captured by the motion capture module; and a sound playing module that is used for playingcorresponding sound according to the picture displayed by the display module; according to the invention, the trainee can watch teaching videos from multiple angles through the display module and themotion capture module, and can know motion exercises before practical training, so that the trainees can learn technical essentials without competing for surrounding teachers, and through the motionexercises before practical training, the probability of dangers caused by misoperation in practical training is reduced.

The invention discloses a safety prompting system of a pure electric vehicle, which comprises a vehicle body, a whole vehicle controller, a sounding device and a seat pressure device, wherein the whole vehicle controller, the sounding device and the seat pressure device are respectively arranged on the vehicle body; The sounding device comprises a sounding relay, a relay switch and a sounding device, the sounding relay, the relay switch and the sounding device are respectively arranged on the vehicle body, one end of the sounding relay is electrically connected with one end of the vehicle controller, and the other end of the sounding relay is grounded. The invention can judge whether the driver leaves the driving seat, and can carry out alarm operation to avoid automobile automatic drivingand safety accident. Moreover, it can be judged that the electric vehicle is in the running state, and the driver can prompt the driver to turn off the vehicle key power when he leaves the vehicle, so as to reduce the safety accident; Improving the safety of automobiles also improves the reliability of automobile monitoring and reduces the probability of hazards.

The invention, which relates to the novel technology of Beidoou satellite communication and industry information application combination, discloses a Beidou satellite-based metro construction hazard source checking method. The method comprises the following steps that: (1), field hazard source checking is carried out and hazard source report is written so as to determine whether a danger exists; if not, daily construction hazard source checking recording is carried out and the flow is stored to a server; and if so, the information is reported to an information service platform; (2), the reported information is classified and danger coefficient delimiting is carried out; the service platform submits a piece of processing suggestion and an information source to a service processing platform; a responsible worker issues a processing notice and analyzes whether the processing notice can be implemented; if not, the information is reported to the information service platform again to carry out analyzing processing; and if so, field processing is carried out and a processing result is reported; and (3), the responsible worker determines the hazard source and locks the contact, and stores the processing flow to the server. According to the invention, large data information sharing and interaction between the metro construction side and the management side can be realized.

The invention discloses a swing arm floor tile laying device, and relates to the technical field of tile laying equipment. The swing arm floor tile laying device comprises a tile laying vehicle and a tile conveying vehicle, the tile laying vehicle comprises a laying mechanism, a clamping mechanism, an adjusting mechanism and a tile laying vehicle body, the laying mechanism comprises swing arms symmetrically arranged on the two sides of the tile laying vehicle body, one ends of the swing arms on the two sides of the tile laying vehicle body are connected with the clamping mechanism, and the other ends of the swing arms on the two sides of the tile laying vehicle body are connected with a driving shaft close to the top end in the tile laying vehicle body; the clamping mechanism comprises a suction cup assembly used for sucking tiles; the adjusting mechanism comprises a first sliding block connected with the driving shaft, second sliding blocks arranged on the two sides of the first sliding block, and pulley assemblies used for sliding the first sliding block and the second sliding blocks; and the tile conveying vehicle comprises a tile conveying vehicle body, and a male cone arranged on the tile conveying vehicle body and a female cone arranged on the tile laying vehicle body are matched and connected through a magnetic attraction structure. Tile laying can be completed efficiently, and the tile laying position is more accurate.

The invention relates to the technical field of a synthesis method of 1-oxacephalosporin-3-epoxymethylene derivatives as a synthetic intermediate of 1-oxacephalosporin for resisting microbes and especially relates to a preparation method of 1-oxacephalosporin-3-epoxymethylene derivatives shown in the formula (I). The preparation method is characterized in that a 1-oxacephalosporin-3-methylene derivative shown in the formula (II) is efficiently and selectively epoxidized into a 1-oxacephalosporin-3-epoxymethylene derivative by hydrogen peroxide in the presence of a catalyst. The 1-oxacephalosporin-3-epoxymethylene derivative and a derivative of a mercaptotetrazole alkali metal salt shown in the formula (III) undergo a reaction and the reaction products are dehydrated under acidic conditions to form a corresponding 1-oxacephalosporin intermediate shown in the formula (IV). The preparation method has the advantages that a halogen addition reaction is avoided; the easily available catalyst is used; a clean and environmentally friendly oxygen source is used; a reaction process is not carried out at a low temperature; equipment corrosion caused by halogens in industrial production is avoided; an investment of expensive special-purpose equipment is reduced; a risk generation rate is greatly reduced; and 1-oxacephalosporin preparation processes are simple and can be operated easily. Therefore, the preparation method has large competitiveness in industrial production.

The invention relates to a pair of IoT (Internet of Things) based smart glasses for bicycling. The smart glasses comprise an observation mechanism, a central control mechanism and two reinforcing mechanisms, wherein the observation mechanism comprises a first drive assembly, a second drive assembly, a support rod, a drive block, a moving frame, a bearing seat, a rotating shaft, a first camera, a projector and two second cameras; each reinforcing mechanism comprises a third drive assembly, a third gear, a connecting rod, a fixing rod, a cushion block, a cushion pad, a pressure sensor and two springs. According to the IoT based smart glasses for bicycling, peripheral pictures can be projected on lenses of the glasses by an athlete through the observation mechanism during cycling, so that theathlete can concentrate during cycling, the probability of danger of the athlete during cycling is reduced, the glasses wearing firmness can be improved by the reinforcing mechanisms, the probabilityof glasses falling is reduced, and practicability of the glasses is improved.

The invention discloses an explosion-proof analysis cabin with an improved safety coefficient, and aims to solve the technical problems that an existing explosion-proof analysis cabin can convey toxicgas in the environment into the cabin, which threatens the health of analysts in the explosion-proof analysis cabin. According to the technical scheme, the explosion-proof analysis cabin with the improved safety coefficient comprises a cabin body, and a fan used for ventilation is arranged on the side wall of the cabin body; a harmful gas detection module is arranged on the outer side wall of thecabin body, the harmful gas detection device is electrically connected with a control module, and the control module is connected with a sealing module used for sealing the fan and an air purification module used for adjusting the air quality inside the cabin body; the sealing module comprises a sealing frame, a sealing plate and a driving piece which are arranged on the inner side of the fan; and the air purification module comprises an air storage unit, a compression unit and a switch unit, the compression unit and the switch unit are both electrically connected with the control module, andthe cabin body is also provided with an air pressure balance module. The effect of improving the safety coefficient of the explosion-proof analysis cabin in a complex environment is achieved.

The invention relates to a digital learning intelligent identification card, in particular to an intelligent identification card which integrates a campus management system and a digital learning real-time feedback system, thereby improving the convenience and practicability of the identification card and being characterized by the intelligent identification card.

The present invention relates to the technical field of the synthesis method of 1-oxacephalosporin-3-epoxymethylene derivatives (formula I), which can be used as intermediates for the synthesis of antimicrobial 1-oxacephalosporins. The method of the present invention is to epoxidize 1-oxacephalosporin-3-methylene derivatives (formula II) efficiently and selectively with hydrogen peroxide under the action of a catalyst to obtain 1-oxacephalosporin- 3-epoxymethylene derivatives. The corresponding 1-oxacephalosporin intermediate (formula IV) can be prepared by reacting the epoxide with a mercaptotetrazolium alkali metal salt (formula III) derivative, and then dehydrating under acidic conditions. The method of the present invention avoids the halogen addition reaction, the required catalyst is cheap and easy to obtain, the oxygen source used is clean and environment-friendly, the reaction process does not require low temperature, avoids the equipment corrosion caused by the passage of halogen in industrial production, and reduces the cost of expensive special equipment. The investment also greatly reduces the probability of danger, and makes the preparation of 1-oxacephalosporin simple and easy, so it has greater competitiveness in industrial production.

The invention discloses a sleeve buckle device with a waste recovery function for garment processing. The device comprises a bottom plate, and two sliding grooves are formed in the top face of the bottom plate. A horizontal first screw rod is movably mounted between the inner walls of the two sides of the front sliding groove; a movable plate is arranged above the bottom plate in a matched mode, vertical supporting rods are fixedly installed at the four corners of the bottom face of the movable plate respectively, screw holes are formed in one sides of the bottom ends of the two supporting rods located in the front, the first screw can penetrate through the screw holes, and the bottom ends of the two supporting rods located in the front can be in contact fit with the inner wall of the bottom end of the sliding groove located in the front. According to the invention, cloth can be flatly laid on the moving plate by an operator, as pressing rod flattens the cloth, presses the two ends ofthe cloth and then conducts button sewing operation, after the button sewing operation is finished, the cloth is driven by the moving plate to return to one side of the bottom plate, in the process, an operator can check sleeve buttons on the cloth, defective products are removed, and the percent of pass is increased.

A buckle device for garment processing with the function of recycling waste materials, comprising a bottom plate, two chute troughs are provided on the top surface of the bottom plate, and a horizontal first screw rod is movably installed between the inner walls on both sides of the chute in front, and the top of the bottom plate is equipped with The mobile plate, the four corners of the bottom surface of the mobile plate are respectively fixedly installed with vertical support rods, and screw holes are provided on the bottom side of the two support rods in the front, the first screw rod can pass through the screw holes, and the two support rods in the front are provided with screw holes. The bottom end can contact and cooperate with the bottom end inner wall of the chute positioned ahead. Through the present invention, after the operator lays the cloth on the moving plate, the pressing bar will smooth the cloth and press the two ends of the cloth, and then perform the buttoning operation, and after the buttoning operation is completed, the cloth is moving Driven by the board, it returns to one side of the bottom board. During this process, the operator can check the buckles on the fabric, remove defective products, and improve the pass rate.

The invention discloses a three-phase power factor correction device. The three-phase power factor correction device comprises a three-phase change-over switch group, three inductors and three filter capacitors, wherein the three-phase change-over switch group is coupled between a first output end and a second output end; all the inductors are coupled with the three-phase change-over switch group; the three-phase change-over switch group receives the three-phase electromagnetic interference filtering voltage through the inductor and converts the three-phase electromagnetic interference filtering voltage into a direct-current voltage; and all the filter capacitors are respectively coupled with all the inductors and are coupled with the second output end, each filter capacitor is connected between the corresponding inductor and the second output end, and all the filter capacitors filter common-mode noise of three-phase electromagnetic interference filtering voltage so as to reduce the probability of danger.

The invention discloses an explosion-proof analysis hut with improved safety factor, aiming to solve the problem that the existing explosion-proof analysis hut will transport toxic gas in the environment into the hut, which will threaten the health of analysts inside the explosion-proof analysis hut The main points of the technical solution are to include the house body, the side wall of the house body is provided with a fan for ventilation; the house body side wall is provided with a harmful gas detection module, the harmful gas detection device is electrically connected to a control module, and the control module is connected to a control module for sealing. The closed module of the fan and the air purification module for adjusting the air quality inside the house; the closed module includes a closed frame, a closed plate and a driving part arranged inside the fan; the air purification module includes an air storage unit, a compression unit and a switch unit , the compression unit and the switch unit are electrically connected to the control module, and an air pressure balance module is also arranged on the house. The effect of improving the safety factor of the explosion-proof analysis cabin in a complex environment is achieved.

The invention discloses a heat dissipation and anti-seismic protection device for a vehicle-mounted air conditioner compressor, which includes a box body, a support plate, a compressor, a ventilation pipe, a first runner, a first belt, a second runner, a motor, a second belt, and fan blades , base plate, bolts, columns, first spring, buffer pad, fixed column, fixed block, second spring and splint. The vehicle-mounted air-conditioning compressor heat dissipation and anti-seismic protection device has a simple structure and is easy to operate. Through the cooperation of the spring and the buffer pad, the vibration frequency of the compressor is reduced, and the damage to the compression caused by the bumps when the car is running is avoided. The risk of damage to the compressor is reduced, and the splint avoids the left and right shaking of the compressor when the car is bumped, which reduces the maintenance risk and improves the service life; when the compressor is working, it drives the fan blades to rotate at the same time, so that the inside of the box The air circulation avoids the damage to the compressor caused by the high temperature generated when the motor is working, and reduces the probability of danger.

The invention discloses an anti-falling LED hand lamp which comprises a lamp body and a pull rope. Three protection plates are evenly arranged on the outer side of the lamp body at equal intervals, springs are arranged between the protection plates and the lamp body, and when the lamp body falls down from a high position, the anti-falling LED hand lamp is different from the prior art; in the actual using process, the falling lamp body is protected against damage through cooperation of the protection plate and the spring, meanwhile, the protection plate is deflected by impacting the protection plate, then a first shaft is driven to rotate, a second fluted disc is driven to rotate, then a locking pin is driven to move to unlock a disc body, a tension spring drives a driving plate and a driving rod to move downwards, and then a first rack is driven to move; and then the first fluted disc is driven to rotate so that the blocking rod is driven to deflect and turn out, the lamp body is prevented from rolling or sliding, the distance that the lamp body continues to move along the slope after falling is shortened, the difficulty that a user recycles the lamp body is reduced, and meanwhile the probability that the user is in danger is decreased.

The invention discloses a fuel gas plug valve, and belongs to the field of plug valves. A plug protective sleeve of a gas sensor is mounted on the upper side of a plug valve body, and an open circuitcontroller in an external chamber is electrically connected with the gas sensor through an external controller. The gas sensor transfers fuel gas leakage information to the external controller, the external controller transfers alarm information to the open circuit controller in the external chamber, and the open circuit controller in the external chamber cuts off an indoor power supply to minimize the occurring probability of risks; a fuel gas leakage auxiliary alarm mechanism is additionally arranged on the plug valve body, so a alarm gas bag can be supported by a fuel gas when fuel gas leakage occurs, and thus the alarm gas bag is subjected to self deformation to extend to the outer side of the plug valve body, the reminder is timely and obvious, the fuel gas leakage alarm can be effectively assisted, users are reminded timely to take safety measures such as overhaul, and the potential safety hazard of the gas leakage caused by improper use or installation problems is greatly reduced.

The invention discloses a three-phase power factor correction device, which comprises a three-phase switch group, three inductors and three filter capacitors. The three-phase switch group is coupled between a first output terminal and a second output terminal. All inductors are coupled to the three-phase transfer switch group. The three-phase switch group receives the three-phase electromagnetic interference filtering voltage through the inductor, and converts the three-phase electromagnetic interference filtering voltage into a DC voltage. All filter capacitors are respectively coupled to all inductors and to the second output terminal, each filter capacitor is connected between the corresponding inductor and the second output terminal, and all filter capacitors filter out the common of three-phase electromagnetic interference filtering voltages Moderate noise to reduce the probability of danger.

The invention discloses a reinforced fracture-resistant road-bridge pavement slab which comprises a first pavement slab and a second pavement slab. A second steel plate is mounted at the top end of each of the first pavement slab and the second pavement slab, a first concave block, a second concave block and a first inserting plate penetrate two sides of a second inserting plate, the bottom ends of two sides of a first steel plate are connected with the first pavement slab and the second pavement slab, a screw penetrates the first steel plate and the second inserting plate, a bearing is fixedon the front of a first fixing block through a rotating rod, a supporting rod is mounted at the left end of the bearing, a convex block is mounted on the left side of the top end of the supporting rod, and the outer wall of the convex block is connected with a third concave block. Through cooperation of the first concave block and the second concave block, the supporting rod clockwise rotates through the bearing to be buckled with the third concave block to mount a tension spring on the surface of the supporting rod to the end of the second inserting plate, so that probability of danger is lowered, and traffic accidents caused by fracture of the pavement slab are reduced effectively.

The invention relates to a pair of IoT (Internet of Things) based smart glasses for bicycling. The smart glasses comprise an observation mechanism, a central control mechanism and two reinforcing mechanisms, wherein the observation mechanism comprises a first drive assembly, a second drive assembly, a support rod, a drive block, a moving frame, a bearing seat, a rotating shaft, a first camera, a projector and two second cameras; each reinforcing mechanism comprises a third drive assembly, a third gear, a connecting rod, a fixing rod, a cushion block, a cushion pad, a pressure sensor and two springs. According to the IoT based smart glasses for bicycling, peripheral pictures can be projected on lenses of the glasses by an athlete through the observation mechanism during cycling, so that theathlete can concentrate during cycling, the probability of danger of the athlete during cycling is reduced, the glasses wearing firmness can be improved by the reinforcing mechanisms, the probabilityof glasses falling is reduced, and practicability of the glasses is improved.

The invention provides an underwater steel platform dismantling device in a narrow and small space and belongs to the technical field of underwater construction devices. The underwater steel platform dismantling device in the narrow and small space comprises a support platform, a sliding platform and a lifting device. The support platform is used for being erected on the water and is convenient to operate. The sliding platform is slidably arranged on the support platform. The lifting device is fixedly connected to the sliding platform and is used for lifting a steel platform. The lifting device can conduct lifting operation on the water. The dismantling device is good in structure stability, the sliding platform can be adopted for conveying the dismantled steel platform, and the danger occurrence probability is reduced with operation on the platform. The dismantling device is convenient to install and disassemble and high in utilization ratio and can be suitable for lifting work under various scenes. A solar charging device is adopted, electricity can be stored at any time under the circumstance that sunlight exists, and energy conservation and environment protection effects are better.

The invention relates to the technical field of constructional engineering, and particularly relates to a desilting device for constructional engineering. The desilting device comprises a desilting shovel mechanism, the desilting shovel mechanism comprises a control rod and a wall body, a shovel head is fixedly mounted at one end of the control rod, extension plates are integrally mounted on two sides of the control rod, a protective shell is arranged on the outer surface of the shovel head, first bolts are mounted at the top ends of the extension plates in a threaded mode, a fixing plate is fixedly mounted at the bottom end of one side of the wall body, and a groove block is integrally mounted at the top end of the fixing plate. According to the desilting device for constructional engineering, by arranging the protective shell, the extension plates and the first bolts, the protective shell shields the whole shovel head, the first bolts are screwed into holes in the protective shell, the protective shell and the extension plates are fixed, and therefore the protective shell plays a good protective role, the shovel head does not accidentally injure staff when the control rod is placed against a wall, the protective performance is improved, and the risk occurrence probability is reduced.

The invention discloses a fuel gas plug valve, and belongs to the field of plug valves. A plug protective sleeve of a gas sensor is mounted on the upper side of a plug valve body, and an open circuitcontroller in an external chamber is electrically connected with the gas sensor through an external controller. The gas sensor transfers fuel gas leakage information to the external controller, the external controller transfers alarm information to the open circuit controller in the external chamber, and the open circuit controller in the external chamber cuts off an indoor power supply to minimize the occurring probability of risks; a fuel gas leakage auxiliary alarm mechanism is additionally arranged on the plug valve body, so a alarm gas bag can be supported by a fuel gas when fuel gas leakage occurs, and thus the alarm gas bag is subjected to self deformation to extend to the outer side of the plug valve body, the reminder is timely and obvious, the fuel gas leakage alarm can be effectively assisted, users are reminded timely to take safety measures such as overhaul, and the potential safety hazard of the gas leakage caused by improper use or installation problems is greatly reduced.