32results about How to "Conditions affecting normal operation" patented technology

The invention relates to an EHT (Extra High Tension) self-cleaning energy-saving environment-friendly device for strengthened heat transfer and descaling in a heat exchange pipe and a manufacture method thereof. The device comprises rotors, a rotating shaft, stoppers and hangers, wherein the plurality of rotors are fixed on the rotating shaft at segments, 2-200 rotors are arranged at each segment, rotors which are limited at each segment have the total length of 100-2000 mm, the rotating shaft is a flexible soft shaft, and the difference between the outside diameter of each rotor blade and the inside diameter of the heat exchange pipe is from 0.1 mm to 3 mm. The manufacture method comprises the following steps of: firstly, respectively manufacturing the rotors, the rotating shaft, the stoppers and the hangers; then, mounting the rotors on the rotating shaft segmentally; limiting the rotors with the stoppers at the tail ends of the rotors at each segment; penetrating the rotating shaft with the rotors into the heat exchange pipe; mounting the hangers at both ends of the heat exchange pipe; and fixing the rotating shaft on the hangers through the stoppers. The EHT (Extra High Tension) self-cleaning energy-saving environment-friendly device and the manufacture method thereof have the advantages of wide sphere of applications, remarkable strengthened heat transfer and descaling effects, convenient counting and measuring, high mounting efficiency and convenient and simple operation.

The invention provides a test bench for detecting a braking distance of a vehicle, and a method for determining he braking distance. The test bench comprises a vehicle supporting platform, and the vehicle supporting platform is used for placing a test vehicle body. The vehicle supporting platform comprises a base platform and a rail wheel set, wherein the rail wheel set is rotatingly disposed on the base platform, and the rail wheel set drives the wheels of the test vehicle body to rotate. An initial wheel set is connected with the rail wheel set, and synchronously rotates with the rail wheel set. The test bench also comprises a control system which is used for controlling the vehicle supporting platform and the test vehicle body. The test system is used for detecting the braking distance of the wheels. The test bench is used for measuring the braking distance of the vehicle, and avoids the impact on the normal operation of the vehicle from the operation of directly pulling the vehicle to an operating rail for the testing of the braking distance of the vehicle. The test bench can effectively shorten the test cycle of the braking distance of the vehicle, and improves the calculation precision and reliability of the braking distance of the vehicle.

The invention provides an overheating early-warning protection device for a computer host, belongs to the technical field of computer host overheating protection. The device comprises a case body, a movable column and a driving air bag, the movable column is sequentially sleeved with a driving ring, a magnetic part, an elastic reset part and a fixing part, an electromagnet corresponding to the magnetic part is arranged in the case body, and an adjusting connecting component is serially connected onto a circuit of the electromagnet. The invention discloses a computer host overheating early warning protection device. The movable warning piece is driven by the driving air bag through the magnetic piece corresponding to the electromagnet; therefore, a computer overheating warning signal can becontinuously and effectively sent to people; people can take corresponding treatment measures to guarantee normal movement of a computer, meanwhile, corresponding heat dissipation and cooling treatment can be carried out in the case body, the situation that normal operation of the computer is affected by overheating is further reduced, and the computer can be automatically powered off when neededso as to prevent internal elements of the computer from being damaged due to the too high temperature.

The invention provides a protection device of a boiler. The protection device comprises a controller, a temperature detector, an automatic adjusting valve, a liquid level detector, a pressure detector, an emptying valve and a safety adjusting valve, wherein the temperature detector, the liquid level detector and the pressure detector are in electric signal connection with a corresponding input end of the controller; the automatic adjusting valve and the emptying valve are connected with a corresponding output end of the controller; a valve hole is formed in the bottom of a valve body of the safety adjusting valve; a steam exhaust hole is formed in the side wall of the valve body of the safety adjusting valve; a limiting baffle plate is arranged at the upper end of an inner cavity of the valve body of the safety adjusting valve; the upper end of a valve rod penetrates through the limiting baffle plate; a valve core, which is propped against the steam exhaust hole, is arranged at the bottom of the valve rod in a sleeving manner; a spring is further arranged on the valve rod in a sleeving manner; the spring is arranged between the limiting baffle plate and the valve core; and a limiting rod horizontally penetrates through the side wall of the valve body and the upper end of the valve rod. According to the invention, the protection device has the advantages that the feedback and regulation are timely, the structure of a safety valve is simple, and the safety performance is high.

The invention provides a grinding device for a joint of a ceramic blank and an application method thereof and relates to the field of ceramic processing. The grinding device for the joint of the ceramic blank comprises a base. Supporting columns are fixedly connected to two sides of the top of the base, a clamping device is welded to the tops of the supporting columns, the clamping device comprises a supporting cover, a lifting mechanism is arranged on the inner side of the supporting cover, the lifting mechanism comprises a sliding cover, and the top of the sliding cover penetrates the bottomof the supporting cover and stretches into an inner cavity of the supporting cover. When the device is used, a ceramic blank body is placed to the top of a lifting table and the ceramic blank body isfurther lifted through the lifting table according to the shape of the ceramic blank body, so that the ceramic blank body can be clamped by the clamping device conveniently, and the ceramic blank body can be safely and conveniently fixed. A winching wheel can winch different positions of the ceramic blank body, so that the joint of the ceramic blank body is ground conveniently.

The invention discloses an anti-rotary type safety valve. A valve port is formed in the bottom of a valve body; a steam exhaust port is formed in the side wall of the valve body; a valve rod with a spring is arranged in the valve body; a valve element at the bottom of the valve rod is abutted to the valve port; first chutes are formed in the two sides of the valve element; limiting sliding blocks suitable for the corresponding first chutes are formed in an inner cavity of the valve body; a sliding rod is arranged at the top end of the valve rod; the interior of the sliding rod is of a cavity structure; second chutes are formed in the inner side wall of the sliding rod; the top end of the valve rod is arranged in the cavity of the sliding rod and is also provided with a protrusion part; and the protrusion part is clamped in the second chutes separately. The anti-rotary type safety valve is stable in structure, high in safety and long in service life and can effectively prevent the valve element and the valve rod from rotating.

The embodiment of the invention provides a flight control method and device for a manned aircraft and the manned aircraft, and the method comprises the steps: respectively calculating the flight state data of the manned aircraft through employing the sensing data collected by a sensor group, and obtaining the flight state data corresponding to each sensor group; identifying the sensor group in a normal state according to the flight state data of all the sensor groups; and controlling the flight of the manned aircraft by adopting the flight state data corresponding to the sensor group in the normal state. According to the method, the flight state data corresponding to the sensor group in the normal state can be selected from the at least two sensor groups to perform flight control on the manned aircraft, so that the manned aircraft can control the manned aircraft by using the redundant flight state data, the situation that errors of the sensor groups affects normal operation of the manned aircraft is avoided; and therefore, the safety of the manned aircraft can be effectively improved.

The invention discloses a sand-spitting cleaning device of dascillidae based on a shock force and warm water immersion method, and relates to the technical field of dascillidae. The sand-spitting cleaning device of dascillidae based on the shock force and warm water immersion method comprises a body, wherein the middle parts of the left and right sides of the inner wall of the body are fixedly connected with supporting blocks, and lower linkage mechanisms are symmetrically arranged at the bottom parts of the two supporting blocks; upper linkage mechanisms are symmetrically arranged at the topparts of the two supporting blocks, and the opposite sides of the two upper linkage mechanisms are respectively fixedly connected with the left and right ends of a cross beam. According to the sand-spitting cleaning device of dascillidae based on the shock force and warm water immersion method, after opening a tank cover by a handle, water is poured into a water tank through a screen, and then thedascillidae is put in a tank body; meanwhile, the tank body and the water tank can be effectively driven to repeatedly shake up and down through the matched arrangement of the lower linkage mechanisms and the upper linkage mechanisms, and the problem that the effect is not good when the sand inside the dascillidae is manually removed is effectively solved.

The invention discloses a bank-note box tongue positioning method, apparatus, equipment and storage medium. The method includes acquiring the positioning instruction of a fan-shaped slice in the bank-note box; controlling the periodical rotation of the fan-shaped slice according to the positioning instruction, controlling the fan-shaped slice in the first period after the preset running time length to turn off a motor, acquiring the level state of a fan-shaped slice sensor after the fan-shaped slice maintains still in the first period, and acquiring the running time length of the current period according to the level state of the fan-shaped slice sensor after the fan-shaped slice maintains still in the previous period in the subsequent period; and if the level of the fan-shaped slice sensor in the current period is at a low level and the level of the fan-shaped slice sensor in the previous period is a high level, turning off the motor according to the running time length of the current period, wherein the tongue in the bank-note box reaches the target position. According to the invention, the tongue positioning is accurate to guarantee the normal work of the bank-note box.

The invention discloses a northbound interface resource export system, which comprises a multi-instance export service and a unified report resource access service, and is characterized in that the multi-instance export service is used for exporting different resource data, generating a file, compressing the file and uploading the file to a cloud server according to different northbound interface standards; and the unified report resource access service is used for completing resource data synchronization, converting the resource data into a unified data model, persistently storing the unified data model in a local database, and ensuring the data instantaneity and the consistency of background data. When the unified northbound resource access module is started, background service data and equipment state data are synchronized to a local database, and local resource data are refreshed in real time; and after receiving the export task, the task assignment module divides the export task into different small tasks according to different resource types, and issues the small tasks to different distributed multi-instance export services. The repeated conversion of the data model is avoided, and the northbound interface resource export efficiency is improved.

The invention provides a die cutting machining center based on linear motor driving. The die cutting machining center comprises a machine tool base body, a lower workbench, an upper workbench, a linear motor and a magnetic plate, wherein the lower workbench is installed on the machine tool base body, the upper workbench is installed on the lower workbench and is used for allowing a die to be placed, the linear motor is installed on the lower workbench, faces the machine tool base body, and is used for driving the lower workbench to do linear motion on the machine tool base body, and the magnetic plate is arranged on the machine tool base body. According to the machining center, a workbench is improved to a split structure, so that the situations that the stress deformation of the workbenches are caused by huge magnetic attraction force generated between the linear motor and the magnetic plate, and then the machining precision and the normal operation condition of the workbenches are influenced are avoided.

The invention is suitable for the fuel cell field and provides a novel hydrogen fuel cell and a hydrogen storage tank. The hydrogen storage tank comprises a hydrogen storage tank body, a gas outlet pipe, a connection channel, an electromagnetic valve, a first inductor and a controller, wherein at least two hydrogen storage chambers for storing hydrogen are arranged in the hydrogen storage tank body; the gas outlet pipe is arranged on one end of the hydrogen storage tank body and is connected to the hydrogen storage chambers; the connection channel is connected between the two adjacent hydrogenstorage chambers; the electromagnetic valve is arranged in the connection channel; the first inductor is arranged in the hydrogen storage chambers and is electrically connected to the electromagneticvalve; and the controller is electrically connected to the electromagnetic valve and the first inductor, and when a first induction signal is received, the controller makes the electromagnetic valveopen. Through arranging the at least two hydrogen storage chambers, the first inductor is used to automatically control opening of the electromagnetic valve, artificial hydrogen supplementation is notneeded, and simultaneously a condition that when gas pressure in the main hydrogen storage chamber is lower than a first preset threshold, that is, when a hydrogen gas is about to be used up, timelysupplement cannot be performed so as to affect normal operation of load appliances connected to a hydrogen fuel cell is avoided.

The invention discloses an unmanned equipment road surface obstacle detection method and device, unmanned equipment and a storage medium. After the point cloud collected by the laser radar in the advancing process of the unmanned equipment is obtained, the suspected obstacle on the advancing path of the unmanned equipment is determined based on the point cloud, the laser radar is controlled to scan the area where the suspected obstacle is located at at least two different angles, at least two frames of target point clouds are obtained, and then the at least two frames of target point clouds are fused to obtain the target obstacle. And on the basis of the dense point cloud, determining a real obstacle on the advancing path of the unmanned equipment. The area where the suspected obstacle is located is scanned at at least two different angles, the density of light spots hit on the suspected obstacle is increased, the resolution of the laser radar and the coverage rate of the point cloud on the suspected obstacle are improved, then the obstacle detection precision is improved, the situation that normal operation of unmanned equipment is affected due to missing detection is avoided, and the detection efficiency is improved. And the safety of the unmanned equipment is improved.

The invention relates to the technical field of robots, and discloses a self-moving robot control method and device and the self-moving robot, which are used for quickly identifying obstacles shielding a cliff sensor and preventing the cliff sensor from continuously reporting abnormities. The self-moving robot control method comprises the steps: controlling the driving wheels to drive the self-moving robot to move to a first position; acquiring a first signal acquired by at least one of a plurality of cliff sensors of the self-moving robot at a first position; if it is judged that the first signal comprises the abnormal signal, controlling driving wheels to drive the self-moving robot to move to a second position according to the abnormal signal; acquiring a second signal acquired by at least one of a plurality of cliff sensors of the self-moving robot at a second position; determining whether the working states of the cliff sensors are abnormal or not according to the first signals and the second signals, and controlling the running state of the self-moving robot according to abnormal conditions.

The invention discloses a concussion force and warm water soaking method-based sand-spitting cleaning device and cleaning method for a nail, and relates to the technical field of nails. The concussionforce and warm water soaking method-based sand spitting and cleaning device for the nail comprises a device body, supporting blocks are fixedly connected to the middle of the left side and the rightside of the inner wall of the device body, lower linkage mechanisms are symmetrically arranged at the bottoms of the two supporting blocks, upper linkage mechanisms are symmetrically arranged at the tops of the two supporting blocks, and the opposite sides of the two upper linkage mechanisms are fixedly connected with the left end and the right end of a cross beam correspondingly. According to theconcussion force and warm water soaking method-based sand-spitting cleaning device for the nail, after the box cover is opened through the lifting handle, water is poured into the water tank throughthe screen, then the nails are put into the box body, meanwhile, the box body and the water tank can be effectively driven to repeatedly shake up and down through the matched arrangement of the lowerlinkage mechanisms and the upper linkage mechanisms, and the problem that the effect is poor due to the fact that sand in the nails is manually removed is effectively solved.

The invention provides a regulating type safety valve for a boiler. A slide rod with a sliding cavity and a limiting rod are arranged in an upper valve body, a valve rod is arranged in a lower valve body, the top end of the valve rod is locked in the sliding cavity in the slide rod, and a spring limiting buckle is fixedly arranged on the valve rod; a spring sleeves the valve rod, and the spring is located between the bottom plate of the upper valve body and the spring limiting buckle and leans against the bottom plate of the upper valve body and the spring limiting buckle; a valve core is further fixedly arranged at the bottom end of the valve rod; a valve port is formed in the bottom of the lower valve body, a steam exhaust port is formed in the side wall, and the valve core leans against the valve port; and the upper valve body and the lower valve body are in threaded connection. The regulating type safety valve for the boiler provided by the invention has the advantages of being simple and rapid to adjust the pressure, stable in structure and high in safety.

The invention provides a battery cell end face forming device. The battery cell end face forming device comprises: a tab alignment assembly, wherein the tab alignment assembly comprises a battery cellclamping arm used for clamping a battery cell, a tab detection sensor used for detecting a tab of the battery cell clamped by the battery cell clamping arm, and a battery cell rotating mechanism usedfor rotating the battery cell clamped by the battery cell clamping arm; a battery cell end face forming assembly, which comprises a first end face forming mold and a second end face forming mold thatare oppositely arranged, wherein the first end face forming mold and the second end face forming mold can move relatively so as to be pressed on the battery cell end face between the first end face forming mold and the second end face forming mold or to loosen the battery cell; and a forming and clamping manipulator, which is arranged between the first end face forming mold and the second end face forming mold and used for moving the battery cell to a position between the first end face forming mold and the second end face forming mold. With the battery cell end face forming device, thermal forming treatment can be conducted on the end face of the battery cell, the overall height of the battery cell can be reduced, and the battery cell is convenient to assemble.

The invention provides a test bench for detecting a braking distance of a vehicle, and a method for determining he braking distance. The test bench comprises a vehicle supporting platform, and the vehicle supporting platform is used for placing a test vehicle body. The vehicle supporting platform comprises a base platform and a rail wheel set, wherein the rail wheel set is rotatingly disposed on the base platform, and the rail wheel set drives the wheels of the test vehicle body to rotate. An initial wheel set is connected with the rail wheel set, and synchronously rotates with the rail wheel set. The test bench also comprises a control system which is used for controlling the vehicle supporting platform and the test vehicle body. The test system is used for detecting the braking distance of the wheels. The test bench is used for measuring the braking distance of the vehicle, and avoids the impact on the normal operation of the vehicle from the operation of directly pulling the vehicle to an operating rail for the testing of the braking distance of the vehicle. The test bench can effectively shorten the test cycle of the braking distance of the vehicle, and improves the calculation precision and reliability of the braking distance of the vehicle.

The invention relates to the field of robot technology, and discloses a control method and device for a self-moving robot, and the self-moving robot, which are used for quickly identifying obstacles blocking cliff sensors and preventing the cliff sensors from continuously reporting abnormalities. The control method of the self-mobile robot includes: controlling the drive wheel to drive the self-mobile robot to move to the first position; obtaining the first signal collected at the first position by at least one of a plurality of cliff sensors of the self-mobile robot; if it is judged that the first signal includes Abnormal signal, then control the drive wheel to drive the self-mobile robot to move to the second position according to the abnormal signal; obtain the second signal collected from at least one of the multiple cliff sensors of the mobile robot at the second position; according to the first signal and the second The signal determines whether the working status of multiple cliff sensors is abnormal, and controls the running status of the self-mobile robot according to the abnormal situation.

The invention relates to the technical field of pumping equipment. In order to solve the problem that the lift of the pumping equipment is too small, the pumping equipment for hole drilling pumping tests is provided. According to the technical scheme, the pumping equipment comprises a mounting bracket, a main rotating member rotating around the horizontal direction, a conveyor belt wrapping on themain rotating member and a main driving member for driving the main rotating member to rotate; the conveyor belt comprises a waterproof layer abutting against the main rotating member and a water absorbing layer located on the side, away from the main rotating member, of the waterproof layer, the mounting bracket is provided with an extruding assembly for extruding the conveyor belt, the extruding assembly comprises an auxiliary rotating member and a guiding member matched with the auxiliary rotating member to extrude the conveyor belt, and the mounting bracket is further provided with an auxiliary driving member for driving the auxiliary rotating member and the main rotating member to rotate in the same direction. Underground water is absorbed through the water absorbing layer of the conveyor belt and is transported to the extruding assembly, the water absorbing layer is extruded to extrude out the underground water absorbed in the water absorbing layer, the guiding member is used for flow guide and collection to bring out underground water in a deep drilled hole so as to conduct the hole drilling pumping tests.

The invention relates to a service scheduling method and device, electronic equipment and a storage medium. The method comprises the following steps: receiving a service calling request sent by a terminal; obtaining load information of each micro-service instance, wherein the load information is used for representing the capability of processing the service calling request of each micro-service instance and the processing state of the current service calling request; and determining a target micro-service instance in the micro-service instances according to the load information, and sending the received service calling request to the target micro-service instance. In this way, the micro-service instance with the good service calling request processing state and the good processing capacity can be effectively selected from the multiple micro-service instances, and then the situation that normal operation of the micro-service is affected due to the fact that the micro-service instance with the insufficient processing capacity is selected can be avoided.

The invention relates to a measured data-based doubtful point discrimination method, and aims at solving the disadvantage that the existing field measurement reported data is unreal so that the search of doubtful data is low in accuracy and low in speed. The method comprises the following steps of: 1, obtaining a matrix of distances between positions of n measured data; 2, when i is equal to 1, forming a class for each of the n measured data, wherein distances between the classes are the distances between the n measured data; 3, when i is equal to 2, combining two classes, the distance between which is the minimum, obtained in step 2 to form a new class, and calculating the distances between the new class and the other classes to obtain a matrix of new class distances; 4, when i is equal to m, combining two classes, the distance between which is the minimum, obtained when i is equal to m-1 to form a new class; 5, obtaining the number of the classes and members of each class; and 6, discriminating doubtful degrees of doubtful point data. The method provided by the invention is used for the field of data doubtful point discrimination.

The invention provides a regulating type safety valve for a boiler. A slide rod with a sliding cavity and a limiting rod are arranged in an upper valve body, a valve rod is arranged in a lower valve body, the top end of the valve rod is locked in the sliding cavity in the slide rod, and a spring limiting buckle is fixedly arranged on the valve rod; a spring sleeves the valve rod, and the spring is located between the bottom plate of the upper valve body and the spring limiting buckle and leans against the bottom plate of the upper valve body and the spring limiting buckle; a valve core is further fixedly arranged at the bottom end of the valve rod; a valve port is formed in the bottom of the lower valve body, a steam exhaust port is formed in the side wall, and the valve core leans against the valve port; and the upper valve body and the lower valve body are in threaded connection. The regulating type safety valve for the boiler provided by the invention has the advantages of being simple and rapid to adjust the pressure, stable in structure and high in safety.

The invention provides a die cutting machining center based on linear motor driving. The die cutting machining center comprises a machine tool base body, a lower workbench, an upper workbench, a linear motor and a magnetic plate, wherein the lower workbench is installed on the machine tool base body, the upper workbench is installed on the lower workbench and is used for allowing a die to be placed, the linear motor is installed on the lower workbench, faces the machine tool base body, and is used for driving the lower workbench to do linear motion on the machine tool base body, and the magnetic plate is arranged on the machine tool base body. According to the machining center, a workbench is improved to a split structure, so that the situations that the stress deformation of the workbenches are caused by huge magnetic attraction force generated between the linear motor and the magnetic plate, and then the machining precision and the normal operation condition of the workbenches are influenced are avoided.

The cell end face forming mechanism includes: a component mounting plate; a cell end face forming component arranged on the component mounting plate, the cell end face forming component includes a first end face forming die and a second end face forming die oppositely arranged, The first end face forming die and the second end face forming die can move relatively; the first end face forming assembly includes a first end face forming tooling, the second end face forming assembly includes a second end face forming tooling, and the first end face forming assembly includes a second end face forming tooling. The first end surface forming tool and / or the second end surface forming tool is provided with tab avoidance positions. The invention can perform thermoforming treatment on the end face of the electric core, which is beneficial to reducing the overall height of the electric core and facilitating the assembly of the electric core.

The invention discloses a bank-note box tongue positioning method, apparatus, equipment and storage medium. The method includes acquiring the positioning instruction of a fan-shaped slice in the bank-note box; controlling the periodical rotation of the fan-shaped slice according to the positioning instruction, controlling the fan-shaped slice in the first period after the preset running time length to turn off a motor, acquiring the level state of a fan-shaped slice sensor after the fan-shaped slice maintains still in the first period, and acquiring the running time length of the current period according to the level state of the fan-shaped slice sensor after the fan-shaped slice maintains still in the previous period in the subsequent period; and if the level of the fan-shaped slice sensor in the current period is at a low level and the level of the fan-shaped slice sensor in the previous period is a high level, turning off the motor according to the running time length of the current period, wherein the tongue in the bank-note box reaches the target position. According to the invention, the tongue positioning is accurate to guarantee the normal work of the bank-note box.

The invention relates to the technical field of pumping equipment. In order to solve the problem that the lift of the pumping equipment is too small, the pumping equipment for hole drilling pumping tests is provided. According to the technical scheme, the pumping equipment comprises a mounting bracket, a main rotating member rotating around the horizontal direction, a conveyor belt wrapping on themain rotating member and a main driving member for driving the main rotating member to rotate; the conveyor belt comprises a waterproof layer abutting against the main rotating member and a water absorbing layer located on the side, away from the main rotating member, of the waterproof layer, the mounting bracket is provided with an extruding assembly for extruding the conveyor belt, the extruding assembly comprises an auxiliary rotating member and a guiding member matched with the auxiliary rotating member to extrude the conveyor belt, and the mounting bracket is further provided with an auxiliary driving member for driving the auxiliary rotating member and the main rotating member to rotate in the same direction. Underground water is absorbed through the water absorbing layer of the conveyor belt and is transported to the extruding assembly, the water absorbing layer is extruded to extrude out the underground water absorbed in the water absorbing layer, the guiding member is used for flow guide and collection to bring out underground water in a deep drilled hole so as to conduct the hole drilling pumping tests.

The invention discloses an operation panel for a dyeing machine. The operation panel comprises a panel body, a temperature control panel is installed on the left side of the upper portion of the panel body, and a temperature display screen and temperature control keys are installed on the temperature control panel; a program setting panel is installed on the right side of the upper portion of the panel body, and a program display screen and program selection keys are installed on the program setting panel; five rows of components are transversely arranged in the middle and on the lower portion of the panel body and sequentially are the first-row components, the second-row components, the third-row components, the fourth-row components and the fifth-row components, and the first-row components, the second-row components, the third-row components and the fourth-row components are arranged in an array mode. The operation panel for the dyeing machine achieves the advantages of being compact in layout, reasonable in structure, safe and understandable in operation, high in practicability and convenient to use.