223results about "Mechanical audible signalling" patented technology

The invention discloses a printing machine accessory installation precision detection device and method, and belongs to the technical field of printing machine accessory detection, the printing machine accessory installation precision detection device comprises a working plate, a motor and a material box, the lower surface of the working plate is in threaded connection with a support, the interior of the working plate is fixedly connected with a limiting rod, and the working plate is symmetrically distributed about the center of the limiting rod; the motor is in bolted connection with the outer wall of the working plate on the left side; and the spray head is fixedly connected to the tail end of the inner connecting pipe of the vertical plate. When the printing machine accessory installation precision detection device works, printing machines provided with printing rollers are tidily placed in front of a detection high-definition probe, then a motor is started, when the motor works, an equipment box and the detection high-definition probe are driven to move in the horizontal direction through a threaded rod and a limiting rod, workpieces are detected, and when defective products are detected, the printing rollers are driven to move in the horizontal direction. And marking liquid is sprayed through the spray head to mark the defective products, so that the defective products can be conveniently treated by workers.

The mining lithium battery protection device comprises a battery box body, a fire extinguishing trigger mechanism, a fire extinguishing assembly and an acoustic early warning unit, the interior of the battery box body is divided into a battery cabin and an auxiliary cabin which are distributed up and down through a sealing partition plate, the interior of the battery cabin is used for containing a lithium battery pack, and the fire extinguishing trigger mechanism comprises a communicating pipeline and a valve; the fire extinguishing assembly comprises a fire extinguishing agent container, the output end of the fire extinguishing agent container is located on one side of the lithium battery pack, and the valve is used for controlling the output end of the fire extinguishing agent container to be opened and closed. The acoustic early warning unit comprises a brass whistle, the air inlet end of the brass whistle is communicated with the auxiliary cabin, and the sound outlet of the brass whistle is located outside the battery box body. A mechanical fire extinguishing and early warning triggering mechanism is adopted, electric power work is not depended, the structure is simple and stable, and the early warning and fire extinguishing actions are prevented from being influenced by factors such as power failure and electronic element damage.

The utility model discloses an air-breathing smoke-sensing fire alarm device, and relates to the technical field of fire alarm. The flash lamp comprises a mounting plate, a shell is fixedly connected to the front face of the mounting plate, a flash assembly is arranged on the front face of the shell, an air inlet is formed in the right side of the shell, a flowing pipe is fixedly connected to the inner wall of the shell, and an air outlet is formed in the left side of the mounting plate; a rotating ring is fixedly connected to the back face of the flash cover, and a round hole is formed in the front face of the shell. According to the utility model, the bell is arranged, specifically, the rotating ring can drive the knocking block to rotate together during rotation, the bell is knocked after the knocking block is in contact with the bell, so that vibration and sound production are generated, the bell can be continuously knocked and sound can be produced by such reciprocating operation, and the volume can be increased by the knocking mode, so that surrounding people can be better reminded; the warning effect can be effectively achieved in a noisy area with few crowds, and safety is improved.

The utility model discloses a lithium ion battery with a self-protection function, and relates to the technical field of lithium ion batteries. The lithium ion battery with the self-protection function comprises a battery box, an indicating lamp, a wiring port and a leakage protector are arranged at the front end of the battery box, main heat dissipation holes are formed in the bottom of the battery box, auxiliary heat dissipation holes are formed in the two sides of the battery box, and a heat dissipation fan and a control host are arranged at the inner bottom of the battery box; a hollow bottom plate is fixedly connected to the interior of the battery box, a heat conduction partition plate is arranged on the hollow bottom plate, a lithium ion battery is fixedly connected to the interior of the heat conduction partition plate, and a temperature sensor is arranged on the heat conduction partition plate. And when the heat dissipation fan still cannot meet the heat dissipation requirement after being started, the sliding plate can automatically move upwards to open the auxiliary heat dissipation holes to enhance heat dissipation, so that the lithium ion battery is prevented from being overheated.

The invention discloses a residence elevator shaft accumulated water measuring and alarming device which comprises a measuring and alarming box. A water level measuring line used for measuring the water level of accumulated water is engraved on the side face of the side, facing the middle of the elevator shaft, of the measuring alarm box, the knocking alarm mechanism is installed on the upper side in the measuring alarm box, the top of the knocking alarm mechanism communicates with an alarm water level inlet, and water collecting tanks installed at the bottom in the measuring alarm box are arranged at the bottom at intervals; an automatic drainage control system is arranged on the side, away from the one-way drainage valve port, of the water collection tank, the knocking alarm mechanism comprises a lifting type swing assembly arranged on the upper side in the measurement alarm box, the top of the lifting type swing assembly is communicated with the alarm water level inlet, and the lifting type swing assembly is provided with a knocking alarm part in a pressing contact mode. According to the device, mechanical structure matching is adopted in the whole process, and compared with electronic equipment, the device has extremely high safety and durability.

The present invention discloses a new energy vehicle charging pile anti-collision alarm device in the technical field of vehicle charging piles, comprising a charging pile base, a plurality of cams connected to the protective frame for uniform rotation, a plurality of movable plates arranged inside the protective frame, a bell installed at one end of the movable plate by screws, four drive switches evenly arranged around the bottom of the charging pile base, a first spring telescopic rod installed by screws at the positions of the drive switches around the inner wall of the protective frame. Compared with the prior art, the present invention has the following beneficial effects: the structure of the present invention is scientific and reasonable, and the use is safe and convenient: it is convenient to remind personnel by sound, and the buzzer and the alarm light are driven by electricity to turn on the driving buzzer and the alarm light, so as to further remind personnel by light and sound, realize multiple reminders to personnel, improve the use effect of the alarm device, and synchronously remind personnel by electric drive and mechanical means.

The invention relates to the technical field of gas sensors, and discloses a multifunctional gas sensor and a preparation method thereof.The gas sensor comprises a shell assembly and a fixing assembly, the shell assembly is used for protecting an internal circuit structure, and the fixing assembly is used for installing the shell assembly to an area needing to be detected; by arranging the elastic silk screen, the diameter of the through hole in the expansion pipe is increased in the expansion process of the expansion pipe, in this way, pulling force can be applied to the elastic silk screen, the elastic silk screen is completely unfolded, and in the expansion process of the expansion pipe, due to the fact that the size of the expansion pipe is increased all the time, the circulation amount of the expansion pipe is increased; furthermore, gas in the gas supply pipe can quickly pass through the expansion pipe, gas accumulation at the expansion pipe is relieved, the heat volatilization efficiency during gas flowing is improved, impurities in the gas can be filtered and blocked through expansion of the elastic silk screen, the impurities in the gas are prevented from entering the gas sensing element, and the gas sensing element is prevented from being damaged. The detection result of the gas concentration is influenced.

The invention relates to the technical field of attenuators, and discloses a conductor short circuit type mechanical adjustable attenuator which comprises an attenuator body, and a first interface and a second interface are arranged on the two sides of the attenuator body respectively. A concentric-square-shaped mounting plate is arranged in an inner cavity of the attenuator body, and a knocking plate is arranged in an inner cavity of the concentric-square-shaped mounting plate. According to the invention, when a worker debugs the attenuator body, and when the precision between the worm and the worm gear and the precision between the lead screw and the guide sleeve are not accurate, the number of turns of rotation of the worm is increased, so that the movement track of the concentric-square-shaped mounting plate arranged below becomes more accurate; a knocking plate can horizontally move between a convex block and a groove which are arranged on a mounting plate, so that the knocking plate is overturned, and a worker is reminded of inaccurate precision between a worm and a worm gear or between a lead screw and a guide sleeve and the like at the moment; therefore, workers can conveniently perceive in the debugging process at the first time, and maintenance and replacement are achieved.

The utility model discloses a built-in transformer type mechanical doorbell, which comprises a doorbell mounting casing and a mounting door frame, a mounting clamping plate is mounted at the embedded joint of the rear end of the doorbell mounting casing and the mounting door frame, and a first connecting rotating rod is mounted on the bottom side in the doorbell mounting casing. The middle of the first connecting rotating rod is sleeved with a rotating gear, the top end of the first connecting rotating rod is connected with a first conical tooth, the side face of the rotating gear is in engaged transmission connection with a multi-tooth push rod, and a connecting extrusion assembly is arranged at the rear end of the multi-tooth push rod. The beneficial effects of the utility model are that through the multi-tooth transmission structure and the elastic extrusion reset structure, when the doorbell breaks down, the doorbell can still make a sound, the use continuity is improved, the use effect of the doorbell is also improved by simultaneously reminding inside and outside the door, and the elastic connection mode enables the power transmission to be more stable, and the service life of the doorbell is prolonged. Meanwhile, potential safety hazards are reduced.

A ship navigation assisting device includes: an area setter 304 that sets, for a target ship, a polygonal safe navigation area defined by a plurality of vertices and surrounding the target ship; a collision point calculator 305 that calculates, based on a speed of the own ship, a relative position between the own ship and the target ship, and a velocity vector of the target ship, collision points between each of the plurality of vertices constituting the safe navigation area and the own ship; and a collision danger area calculator 306 that connects the plurality of collision points calculated by the collision point calculator 305 to calculate a collision danger area.

The utility model belongs to the field of municipal engineering, and provides a safety warning device for municipal engineering, which comprises a shell, a safety warning device and a safety warning device, the winding rod is rotatably arranged in the shell; the fluorescent isolation strip is wound on the winding rod, the inner end of the fluorescent isolation strip is fixedly connected with the side wall of the winding rod, and the outer end of the fluorescent isolation strip extends out of the window; the winding assembly is arranged in the shell and used for winding the fluorescent isolation strip; and the lighting assembly is arranged at the top end of the shell. When the safety warning device is used on a construction site at night, even if light is poor, the fluorescent isolation strip has a good warning effect. And the lighting assembly is arranged, so that a certain lighting effect can be achieved, passing personnel and vehicles can conveniently find the safety warning device shell body and the fluorescent isolation strip in time, and the warning effect is improved.

The invention belongs to the technical field of water conservancy projects, and particularly relates to a water level alarm device for water conservancy project construction, which comprises a base, one side of the upper end surface of the base is fixedly connected with a support column, one side of the upper end of the support column is rotatably provided with a rotating roller, the rotating roller is wound with a rope, and one side of the upper end of the support column is provided with a support roller. The rope is attached to the surface of one side of the supporting roller, a shell is fixedly connected to the end of the rope, an alarm is arranged on one side of the upper end of the shell, two first sliding rods are slidably connected to one side of an inner cavity of the shell, and a lifting plate is fixedly connected to the lower ends of the first sliding rods. By means of the water flow driving type alarm assembly, when the water level rises to the warning line, the edge of the mounting plate is flush with the impact ball, when water flow impacts the floating block, the edge of the mounting plate makes contact with the impact ball, and when the edge of the mounting plate makes contact with the impact ball, a sound is made to remind a construction party to take emergency measures in time.

The utility model belongs to the technical field of alarm equipment, and particularly relates to an anti-collision rope. Comprising an upper mounting plate, a lower mounting plate, an alarm mechanism and a rope body, the alarm mechanism is fixedly connected to the upper mounting plate and comprises an outer box body, a normally-closed switch is arranged at the top of the outer box body, a trigger block is arranged in the outer box body, the top end of the trigger block makes contact with the normally-closed switch, and a guide column is fixedly connected to the bottom end of the trigger block; the bottom end of the guide column downwards penetrates through the bottom wall of the outer box body to be fixedly connected with one end of a rope body, the other end of the rope body is fixedly connected with the lower mounting plate, the guide column is sleeved with a first spring, and an alarm is arranged on the outer wall of the outer box body and connected with an external power source through a normally-closed switch. The car washing rope can be installed on the two sides of a car washing shed, when the rope body is touched, the rope body can pull the trigger block downwards, the trigger block is made to be separated from the normally-closed switch, the alarm can give an alarm, and therefore a driver is reminded to stop the car immediately, and collision accidents are avoided.

The invention discloses a mining audible and visual alarm based on a mining area environment, and belongs to the technical field of alarm devices. The alarm comprises a box body, and a monitoring sensor and an alarm assembly are arranged in the box body; the alarm assembly performs corresponding actions by monitoring a vibration signal sent by the sensor, and the alarm assembly comprises a sound production assembly, a transmission mechanism and a hydraulic adjusting system; the sound production assembly comprises a plurality of iron pipes, and sound production holes are formed in the iron pipes; the plurality of iron pipes are annularly distributed in sequence according to the diameter size; the transmission mechanism comprises a knocking rod and can enable the knocking rod to knock the iron pipe; the hydraulic adjusting system comprises an oil cylinder and a fixing ring, and a round pipe connected with the fixing ring slides in the iron pipe, so that the round pipe is far away from or close to the sound production hole in the iron pipe; the mining audible and visual alarm solves the problem that a traditional mining audible and visual alarm cannot carry out distinguished early warning according to audible and visual signals with different intensities, and misjudgment is caused.

The invention relates to the technical field of hub detection, and discloses hub balance detection equipment which comprises a supporting unit, a roundness detection unit and a warning alarm unit. According to the marking device, when the roundness of the surface of a hub cannot meet the requirement, the hub can extrude an ejector rod to move downwards, the ejector rod moves downwards to drive a clamping block at the tail end to move, the clamping block slides on a guide block, then the position of a marking pen on the guide block is driven to change, a worm can further drive a lead screw shaft to rotate, and the marking pen is driven to rotate. The storage hopper and the grid paper are driven to move through the lead screw lantern ring, then a curve can be drawn on the grid paper through the marking pen, whether the roundness of the hub meets the requirement or not can be obtained by observing whether the difference between the highest point and the lowest point of the curve is within a reasonable range or not, it is guaranteed that the balance degree is kept when the hub rotates, and the service life of the hub is prolonged. The detection of the roundness can be completed in a mechanical mode, the reliability is higher, and the later maintenance cost is low.

The utility model discloses a CO2 capture and storage injection monitoring device which comprises a bottom plate, the top of the bottom plate is fixedly connected with a storage box, the top of the bottom plate is fixedly connected with a frame, the top of the bottom plate is fixedly provided with a motor through bolts, the output end of the motor is fixedly connected with a threaded rod, and the top of the surface of the threaded rod is in transmission connection with a second gear. The surface of the second gear is engaged with a first gear, and the bottom of the first gear is fixedly connected with a second rotating rod. The motor drives the threaded rod to rotate, the threaded rod drives the second gear to rotate, the second gear drives the first gear to rotate, the first gear drives the second rotating rod to rotate, the second rotating rod drives the rubber plate to rotate, and the rubber plate is in contact with the surface of the knocking plate and drives the knocking plate to rotate while rotating. When the knocking plate makes contact with the rubber plate, large knocking sound can be generated, an operator can be reminded through continuous knocking sound, and the monitoring efficiency is improved.

The present invention discloses a smart classroom interactive teaching platform, including a base and a mounting platform, wherein two moving wheels are installed at both ends of the bottom of the base by screws, and the mounting platform is fixedly installed on the top of the base, and also includes: a sleeve is installed on the upper screw of the mounting platform, and the internal slot of the sleeve penetrates through the sliding installation of a lifting platform, and the upper screw of the lifting platform is installed with a mounting plate. The smart classroom interactive teaching platform uses slots at both ends of the top of the first display screen to rotate and install limit blocks through the first extrusion spring. When the two second display screens are pulled to move their positions, the two first extrusion springs will automatically pop out the two limit blocks into a row of limit slots opened on the outside of the two rows of second display screens through their own elastic force. At this time, the two second display screens can be slidably limited to avoid the phenomenon of misalignment and offset of the two second display screens during teaching in the later stage.

The utility model discloses a central water outlet high-pressure pump with a pressure maintaining device for a machine tool, which relates to the technical field of high-pressure pumps and comprises a high-pressure pump body, a pressure relief pipe and a rotating shaft extending to the outer side of the pressure relief pipe, an impeller is mounted on the portion, located on the outer side of the pressure relief pipe, of the rotating shaft, and an elastic connecting assembly is mounted at the top end of the rotating shaft. A clicker is mounted at a pipe orifice on one side, close to the rotating shaft, of the pressure relief pipe. Through the arrangement of the impeller, a worker can know the pressure relief condition by observing the rotating speed of the impeller, through the arrangement of the elastic connecting assembly and the clicker, when the pressure relief amount of the high-pressure pump body is out of a preset range, airflow enables the impeller to rotate at a high speed, and the rotating shaft drives the elastic connecting assembly to rotate at a high speed; the elastic connecting assembly extends under the action of overlarge centrifugal force, the elongated elastic connecting assembly knocks the clicker to make a sound and give a noise alarm in the rotating process, even if sensor equipment in the prior art breaks down, the elastic connecting assembly can be matched with the clicker to give an alarm, and the alarm effect is more stable and reliable.

The invention relates to the technical field of mutual inductor detection, and particularly discloses a current transformer fault alarm device, which comprises a current transformer body and an alarm, and is characterized in that when the current transformer body is abnormal, the current transformer body can shake, and a driving mechanism in the alarm can be driven to work under the shaking condition, so that the current transformer body is prevented from being damaged. The driving mechanism is used for driving the striking mechanism to strike the alarm bell, so that a sound is made to attract a worker, mechanical alarm can be realized through synchronous transmission of the driving mechanism and the striking mechanism, and misjudgment and other conditions in a strong electromagnetic environment can be avoided through mechanical alarm. Moreover, the work of the alarm is not affected by the temperature and humidity of the environment, and meanwhile, the later maintenance is facilitated, and the maintenance cost is reduced.

The invention relates to a cooking vessel (1) comprising a cap (2) equipped with an end wall (3). According to the invention, the end wall (3) comprises a housing (6) accomodating at least one bimetallic element (30a, 30b) that adopts a cold stable first position when the temperature is below a predetermined temperature and toggles into a hot stable second position when the temperature is above the predetermined temperature, and vice versa, the transition from the first stable position to the second stable position generating an audible signal designed to be perceived by a user or by an external device.

The invention relates to the technical field of vacuum ring main units, and provides an air-insulated high-voltage vacuum ring main unit which comprises a ring main unit body, the inner wall of the ring main unit body is fixedly connected with an air pressure sensor and a positioning seat, and the inner side of the positioning seat is rotatably connected with an air collecting pipe; the support frame is fixedly connected to one side of the ring main unit main body, one side of the support frame is fixedly connected with a concentration box, and one end of the concentration box is fixedly connected with a control panel; the gas guide assembly is arranged at the top end of the concentration box and used for being matched with the supporting frame to guide the SF gas out of the ring main unit body; and the warning assembly is assembled at the top end of the concentration box and used for warning nearby personnel, and the air guide assembly comprises an air guide fan. According to the technical scheme, the problems that in the prior art, when SF gas in the device leaks, due to the lack of effective treatment measures, it is difficult for surrounding operators to find the leakage in time, and accidents are extremely likely to happen are solved.

The invention belongs to the technical field of electrician instruments and meters, and particularly relates to a charging pile safety detection and alarm device which comprises a box body and a box cover, a detection device is installed in the box body, an interface seat is arranged on the detection device, an insertion groove is formed in the interface seat, a protection cover is installed on the interface seat, and the protection cover is provided with an alarm device. A temperature sensor is mounted in the interface seat; a locking groove is formed in the inner wall of the inserting groove, a guiding inclined face is arranged at the lower end in the locking groove, a clamping block is slidably installed in the locking groove, and a silica gel layer is arranged on the surface of the clamping block; an electromagnet is installed in the detection device, and the clamping block is connected to the electromagnet through an ejector rod. The arc-shaped rod is made of shape memory alloy, and a heat pipe is installed in the ejector rod. The device is simple in structure, and can give an alarm in time and automatically disconnect the charging gun and the interface seat when an abnormal condition occurs.

The utility model discloses an automatic alarm precipitation well protection device, which comprises a bottom frame, a solar panel, an alarm and a storage battery, a bottom plate is fixed above the bottom frame, a hollow column is fixed in the middle above the bottom plate, a top plate is fixed at the top of the hollow column, the solar panel is arranged above the top plate, and the alarm is arranged above the solar panel. An alarm is fixed to the middle of the top plate, mounting nails are mounted on the surface of the bottom plate, a connecting rod is arranged on the surface of the hollow column, a movable rod is connected to the surface of the connecting rod, a supporting plate is fixed to the end of the movable rod, a clamping groove is formed in the surface of the supporting plate, and fixing blocks are fixed to the two ends of the surface of the connecting rod. According to the dewatering well protection device with the automatic alarm function, the adjustable connecting rod and the movable rod can be used in cooperation with the supporting plate and the vertical plate, the device can conveniently support the inner walls of dewatering wells with different diameters, and the protection effect of the device on the dewatering wells is improved.

The invention discloses a nitrogen pressure adjusting device based on a mainboard control electromagnetic valve, and relates to the field of pipeline pressure adjustment. A nitrogen pressure adjusting device based on a mainboard control electromagnetic valve comprises the electromagnetic valve, a mainboard box for controlling the mainboard is installed on the electromagnetic valve, the air inlet end and the air outlet end of the electromagnetic valve are connected with an air inlet pipe and an air outlet pipe respectively, and the nitrogen pressure adjusting device further comprises pressure sensors fixedly connected to the air inlet pipe and the air outlet pipe respectively. The pressure sensor is used for detecting nitrogen pressure in the gas inlet pipe and the gas outlet pipe; the air inlet end of the pressure relief tank is communicated with the air inlet pipe; through the arrangement of the pressure relief tank, when a nitrogen conveying pipeline is shut down through the electromagnetic valve, redundant air pressure at the air inlet end can be adjusted, sudden pressure increase caused by the water hammer effect is reduced, the influence of the sudden pressure increase on a sealing piece is reduced, the service life of the sealing piece is effectively prolonged, and the safety of the sealing piece is improved. And long-time use is facilitated.

The invention relates to the technical field of oil well dynamic liquid level measurement, in particular to an explosion-proof dynamic liquid level test device, which comprises: a liquid level measurement component, comprising a casing, a conical well cover and a liquid level meter, a pressure relief component, comprising an air pipe, a protective shell, a gas tank, a microphone, a pressure relief ring, a fixed shell, a push column and a mounting shell arranged at the upper end of the pressure relief ring, and an early warning component; a combination of mechanical and sensor measurement is adopted to increase safety protection, when the internal sensor is damaged and cannot test the accurate value in time, the height of the internal liquid level can be visually checked through a float, and through the pressure relief component, when the pressure inside the oil well suddenly increases, the pressure can be released to the outside through the movement of the internal blocking shell and the push column, so as to relieve the high pressure in the air pipe, and at the same time the early warning component will also emit a warning sound to remind the staff, thereby improving the safety of the device.

The utility model provides a substation high-voltage test safety protection device, and relates to the technical field of high-voltage test safety protection. Fixing bases are evenly and fixedly installed on the edge of the upper end of the fixing table, and the two ends of each fixing base are each provided with a row of connecting holes. All the fixed inner frames are mutually connected to form a layer of protection structure, high-voltage equipment can be directly isolated from the external environment, the firm structure can resist accidental collision, human climbing and the like, irrelevant personnel or objects are prevented from entering dangerous areas from the physical level, and the protection structure is a first firm barrier for guaranteeing the safety of the transformer substation and has good practicability. And then a layer of protection warning structure is formed on the outermost periphery of the high-voltage transformer substation by using the connecting net and the peripheral rods, so that the problem that two layers of protection structures need to be mounted on the periphery of the high-voltage transformer substation because safety protection is required during the test of the high-voltage transformer substation, otherwise, passers-by can easily get close to the high-voltage transformer substation to cause danger is solved.

The utility model discloses an anti-burnout junction box in a photovoltaic power generation system, which comprises a box body, the box body is made of flame-retardant materials, two wiring terminals are arranged in the box body, a diode is fixedly connected between the two wiring terminals, one end of each wiring terminal is fixedly connected with a cable, the side surface of the box body is provided with a raised box, and the raised box is fixedly connected with the two wiring terminals. A pulling sound device is arranged in the protruding box, and the cable is clamped in the pulling sound device. When the cable is excessively dragged, the dragging sound device generates vibration sound to remind installation personnel to pay attention to not causing connection loosening of the cable, so that the installation quality is ensured, and the burning risk increase caused by human factors is avoided.

The invention relates to the technical field of intelligent street lamps, in particular to an intelligent street lamp with a mounting structure. The lamp panel is arranged at the upper part of the lamp post; the maintenance box is arranged at the bottom end of the lamp post, and the maintenance box communicates with the lamp post; the three guide grooves are formed in the outer surface wall of the lamp post; and the three guide plates are slidably mounted on the inner side walls of the three guide grooves correspondingly. Compared with the prior art, through cooperative use of the rotating wheel and the winding disc, convenient lifting of the independent mounting frame is achieved, maintenance of different mounting devices is facilitated, winding and unwinding of the mooring rope can be controlled only through simple rotating operation, then the mounting frame is driven to move up and down along the guide groove, and meanwhile, the mounting frame is driven to move up and down along the guide groove. Unwinding of the winding disc can be limited by using the ratchet wheel and the pawl, so that the mounting frame can be stably used, the working efficiency is improved through the design, single maintenance of mounting equipment is facilitated, and using is more convenient.

A mechanical bell for generating an alert signal. A system for monitoring a person equipped with the bell, the system comprising a microphone and a central unit for analysing the sound detected by the microphone.

The utility model discloses a bird-shaped doorbell which comprises a connecting seat, the top of the connecting seat is fixedly connected with a bird body, the top of the connecting seat is fixedly connected with two rubber columns, the top ends of the two rubber columns are jointly fixed with a metal cylinder, and a connecting frame is rotatably inserted between the inner walls of the two sides of the bird body through a rotating shaft. One end of a rotating shaft of the connecting frame is in key connection with a transmission gear, the top end of the connecting frame is fixedly connected with a connecting spring, and the top end of the connecting spring is fixed with a bird head located at the top of the bird body. According to the utility model, the metal ball at the mouth part of the bird head is knocked on the metal cylinder to realize the door knocking operation, so that the bell knocking operation can still be realized in case of power shortage, and then the other teeth on the sliding block are meshed with the transmission gear again, and the metal ball at the mouth part of the bird head is knocked on the metal cylinder again under the action of the transverse spring, so that the door knocking operation is realized. Therefore, the continuous door knocking action is realized, the door knocking effect is improved, and then the electronic doorbell can make different birds' sounds.