The following is written by one person independently. How many such authors can you meet in your life?
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What is the brand, model and price of the lightest electric moped, and what stores sell it?
It is produced in Beijing, Beijing Shenzhou Judian New Energy Technology Co., Ltd., mainly producing power lithium batteries, with one of the smallest bicycles, ultra-light weight and aluminum alloy body.
The price is 3,000 yuan, and the battery accounts for 1500 yuan. The battery is in the middle of the bicycle bar and inside the bar. You can run 15km on a single charge, which is about 10 ampere-hour capacity, 24 volts. The front wheel drive is adopted, and the motor is installed on the front fork. The plastic rim on the front wheel has internal teeth, which are consistent with the gears on the motor.
Shenzhen ZOOM Ruim, Shenzhen Xinlong Health Industry Development Co., Ltd. (No.Longfa Road, Longhua Sub-district Office, Baoan District, Shenzhen 1 1 Store: No.35, Wenxin 1st Road, Nanhai Avenue, Nanshan District, Shenzhen, 0755-83131. Moped and electric vehicle are different in design, structure, technology, engineering difficulty and safety, so they cannot be confused. Here are their differences.
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Where can I find a Japanese Yamaha electric bicycle monopoly in Qingdao (telephone number)
At present, most of them are smuggled, and the price in 500 yuan is about 1000 RMB. Unlike domestic electric cars, this kind of car is power-assisted. If you don't ride a bike, its motor won't turn, and the riding torque is directly proportional to the driving current of the motor. When your riding torque exceeds a predetermined threshold, the driving current of the motor will linearly decrease. When your riding speed exceeds 16 km/h, the driving current of the motor will decrease linearly. When the bicycle speed exceeds 24 km/h, the driving current of the motor will drop to zero. If the wheel is stuck, you should apply a torque to the pedal of the bicycle for electric maneuver. If the car still doesn't move, cut off the input current of the motor, turn off the switch and restart it. The overall structure of this torque sensor is very reasonable, and it can transmit the torque of rotating transmission parts to a fixed angular displacement sensor, which shows that it has a solid industrial foundation in the material, design and processing of mechanical structure. Similarly, the internal transmission of bicycles was successfully copied in China 40 years ago, and was officially installed on commercial bicycles for sale. Due to the limitation of materials and processing conditions, this reverse engineering technology from physical mapping can never last long. Japanese law stipulates that bicycles should have headlights. Generally, generators driven by friction front wheels are used, and a few of them are drum generators with front wheels, rotating external permanent magnet tiles and fixed internal permanent magnets. A structure similar to the motor pulse tachometer generator in industrial control is adopted, and the generator coil is clamped by soft iron with thorns on both sides. Bicycle generators in the history of China were single-stage structures with external lines. Most mopeds in Japan are three-speed internal transmissions, usually with a central motor, a reduction gear and an overrunning clutch. Most smuggled Japanese moped batteries have reached the cycle life of charge and discharge, and there are original110v chargers. Generally speaking, Suzuki cars have the largest power.
Just entrust the sailor to buy it. Pay attention to taxes, stealing bicycles is a criminal offence in Japan! Japanese mopeds generally use brush motors, and the maximum power of motors on bicycles is stipulated by law. Hua 1.5 yuan to 15 yuan RMB can be converted into power-assisted and electric dual-purpose without changing the original controller. /question/68690 188.html？ si= 1
What kind of bike is the most labor-saving and fast?
700-type tire, 27-inch wheel diameter kilometer racing car is the most labor-saving, but the tire strength is low, and it is still the law that its spokes will prick two holes when embedding grooves, just two at a time, no more or less; You can't drive or pick up people on bumpy roads.
600 yuan/car, bearing material is poor. The normal price is 3,000 yuan/vehicle, at least for bearings in Taiwan Province Province.
Generally, it is recommended to use Japanese-made and smuggled second-hand bicycles, generally 300-500 yuan, ordinary tires with 24-inch, 26-inch, 1 and 3/8-inch sections, which are quite suitable for long-distance riding, such as salesmen who send plane tickets, photos and express delivery, and home appliance maintenance personnel. Imported ones with cross sections of 27 "/kloc-0" and 3/8 "are also very good. Suitable for tall people, generally similar to the front diagonal beam of women's cars. The disadvantage is that tires need to be purchased from rubber enterprises in Taiwan Province Province, such as Jianda Zheng Xin, Jianda and Huafeng, which are not available in many areas. The brand-new bicycles produced by China, a Japanese-funded enterprise, are not as good as the second-hand Japanese bicycles smuggled in. Pay attention to motorcycle locks and handcuff bicycles to fixed water pipes and traffic signs to prevent theft. Mountain bike tires are too wide, suitable for riding on rugged mountain roads, suitable for carrying heavy objects, and it is tiring to ride on urban roads.
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Hello, everyone, hehe, I'm 19 male, a college student. I go to school locally, my home is in the city and my school is in the suburbs, which is about 12 km. Do you recommend buying an electric car or a bicycle?
Please help me choose. Small electric cars are quite fashionable. The basement of electric cars similar to motorcycles is not convenient for road racing, bicycles and mountain bikes are a little heavy.
Thank you! Problem supplement: I don't live in school, get up early for school, come back at noon, and have no classes in the afternoon.
Road racing is preferred. Usually, 700 tires are as thin as sausages. Because the tires are thin and narrow, it is very labor-saving to ride. The vehicle is light in weight and cannot carry loads and goods. The advantage is that it can be conveniently carried in the dormitory and placed beside the corridor or stairs, so as to implement active anti-theft. The disadvantage is that the cross section of the inner tube is small, it is not resistant to vibration, and it is afraid of potholes on the road. Therefore, it is a road racing car, which requires high road quality, and all of them are ordinary brakes. There is no imported disc brake, so the riding speed is fast, the braking ability is weak, the braking sliding distance is long and the safety is poor. Domestic road racing cars are low-priced in 400 yuan, and the normal price is 3000 yuan. This kind of bicycle is sold by fewer people and lost less. Because it is expensive, even if the host goes out to eat food stalls, he will stay within the sight of the other party, always pay attention and take it home at night. Those 30,000-50,000 yuan carbon fiber road racing cars are surprisingly light.
Mountain bike tires are too wide for off-road use and are suitable for bumpy road conditions. Riding is heavier than ordinary 26-inch bicycles with 1 and 3/8 knots.
Battery car? Electric bicycles usually use 12 ampere-hour batteries, and the new batteries will run 15 kilometers. The charge and discharge life of batteries is generally one year. Generally, you will run 10 km continuously after half a year, which is not suitable for you. Besides, ordinary lead-acid batteries are heavy. If lithium batteries are used, in this case, two sets 10 km are needed. The battery is 3000 yuan. Ordinary electric vehicles also have a set of batteries, which need to be modified. There are few domestic enterprises that make power lithium batteries, only a few in Tianjin and Beijing. Ordinary lithium batteries, nickel-hydrogen batteries and nickel-cadmium batteries will explode when used in electric vehicles. Just like you, there is not enough charging time. Fast charging will shorten the charging and discharging cycle of any secondary battery, which is usually called service life. According to your specific situation, buy four sets of lithium batteries and put two chargers at home and school. The one in school is usually continuously charged, because the high-energy battery itself is a bomb. The charger of foreign original moped bicycle has a temperature sensor in the battery pack, and the foreign charger has no peak pulse ultra-high voltage output, so it is unattended when charging. Household chargers charge power lithium batteries, power nickel-hydrogen batteries and power nickel-cadmium batteries. You should not charge them in the dormitory. It is appropriate and safe to pay the person on duty at the door. If the battery is stolen, don't expect to claim compensation.
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Principle of Mechanical Work: Man and Bicycle
Compared with people walking, bicycles are obviously labor-saving and seem to save distance. What happened? Tell me what you know, be more specific!
There were public conclusions decades ago; When people walk, they should raise their center of gravity by 2 cm every step and move forward under the action of tendons and gravity. Cyclists do the same work in the same direction, and they can also slide.
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How to choose a bicycle?
I am a girl, I want to buy a bike to work, which is environmentally friendly and healthy, hehe ~ ~ Good idea!
How to choose a bicycle and what should I pay attention to?
Or do you have any good styles to recommend?
Please give some advice!
Supplementary question: brand? What brand is good?
Several decades ago, China imported bicycles from foreign brands such as Three Guns. Women's bicycles are characterized by high handlebars and distinctive body, which shapes the image of a lady. Please look at the old photos.
At present, Japanese bicycles are generally bought, which can be entrusted to seafarers, and high-end bicycle shops can also purchase imports. There are also smuggled ones.
The security guard in this community caught the car thief again and seized the hydraulic clamp. The ordinary lock broke after three shakes, and the clamp was one foot long. There are also various mandatory keys. After learning the news, I launched a social investigation again and saw several brand-new hydraulic pliers, so I decided it was appropriate to make my own locks. For ordinary citizens, the best policy is to buy idle locks, and then weld some steel bars or pipes on the lock body and hooks. The equivalent contour diameter and scale exceed the opening of ordinary hydraulic tongs, so don't worry. Pay attention to handcuff the car body to a fixed object.
Person in charge of report:
The following are practical and effective safety precautions, with no commercial content. They are updated according to my previous posts. They are all public welfare posts with wide application value. Please post them by the webmaster.
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If you are the police chief, what can you do to deal with bicycle theft?
Person in charge of report:
Responding to the instructions of the great leader Chairman Mao, selecting and training cadres is the key to the success or failure of the revolution. How you choose the car lock determines the safety of your personal property. Now serving the people, providing effective guidance, has a wide range of guiding significance, without any business information from manufacturers, please review in the future:
Now the wrongdoer is too bold to be afraid of your burglar alarm!
The wiring position of the electric car is open, cut off with one knife and become dumb on the spot! Or the rigid anti-theft device in the physical sense is reliable, and those "high-tech alarm products" are virtual. If you are indoors or connected to the local public security department when you call the police, it is ok for someone to check it immediately; With standard and familiar equipment, wiring mode, familiar alarm principle and familiar equipment appearance, no non-standard and self-made equipment is reliable.
You have completely answered the question "What feasible suggestions can relevant departments adopt to prevent bicycles from being stolen". ? Thank you ",because it involves the detailed information of the production enterprise, it was deleted by the network management and published an advertisement. Websites should also learn from Scientific Outlook on Development. For major topics involving public interests, the original investigation report shall be made public.
In the public security department, before the reform and opening up, there were lock detection and lock production management departments, and the locks produced had to be appraised by the public security department.
The public security department knows all kinds of ways for thieves to break locks.
In the early days of reform and opening up, many people called for strengthening the safety of bicycle locks, and there were indeed many such products. As long as I lock my bike on a fixed water pipe, a fixed traffic sign pole and a fixed handrail, thieves really can't open it, cut it and break it. Network management is not allowed to publish the specific contact addresses of related enterprises.
Now there are stainless steel bicycle locks, idling locks, Z-shaped keys, U-shaped keys and carburized and hardened lock hooks. Idle lock is characterized in that common tools, keys and iron sheets can turn the lock core, but keys made of high-strength steel cannot be forcibly opened; The original key can open this lock.
There are thick iron pipe locks, copper locks and locks produced by introducing German technology.
Generally, locks with wholesale price above 35 yuan will do, and locks with wholesale price to 70 yuan will be the highest security level.
There are motorcycle locks with wholesale price 100 yuan/piece in the market.
General wholesale price 50 yuan/lock. Buy 120 yuan/Lock to 180 yuan/Lock in the retail store. The ex-factory price of motorcycle locks hollowed out by Fangtie is more than 60 yuan/piece, compared with 20 yuan/piece in previous years; Motorcycle locks with copper lock bodies used to cost more than 30 yuan/piece, but now 100 yuan/piece. It will be more expensive if you use environmentally-friendly copper materials that meet the recent European requirements.
Taobao has a button digital password bicycle lock, which used to be 60 yuan.
Just look for it in the motorcycle parts wholesale city near your residence. Merchants won't tell the truth, so judge for yourself.
Bicycle locks sold in bicycle shops and bicycle repair shops are basically unsafe.
The locks of several brands recommended by netizens are only safe with high-grade locks from the original factory, and it is not possible to buy the same brand in the retail market.
Bicycle locks recommended by some local small public security bureaus are still low-grade locks, and the profits of merchants are half and half.
Therefore, there is no access system for the sale and production of low-grade bicycle locks, which endangers public interests.
Therefore, this is the work of the public security department, the industrial and commercial bureau and the quality supervision bureau, and should be led by the government.
A broken lock can only be opened with an electric grinder. You can choose an unconventional key to reduce the possibility of theft, or you can choose a lock with lower security to lock the bicycle with a fixed object.
The former has no jobs, but the latter monopolizes resources and power, which is endangering national security!
The biggest obstacle is that what can be done is not allowed to be done, and what cannot be done is in the hands of mediocrity. It's not a question of treatment, but there is no post at all, no access to the laboratory and no use of idle ordinary instruments. If your question recurs in Zhou Enlai, it will be easy to solve. And the locks that meet your requirements have been on the market for a long time, from molds to production lines. There is no need for scientific research, re-development and re-investment. There is nothing in the hardware market and bicycle retail market, and citizens have no ability to judge and investigate.
Some simple suggestions:
The lock hook is larger than 15mm in diameter and is generally made of low carbon steel. The wholesale price below 25 yuan is not carburized, and the hardness is not enough, so it can be cut. Carburizing is called "hardening type" in the commodity. Another way to judge whether carburizing is completed is to use a manual saw blade or a steel saw blade with a length of 300mm, a thickness of 0.64mm and a width of 12 or 13mm. The carburized lock hook can't be sawed in, and the saw blade slides straight on the lock hook. Accordingly, the effective diameter of the chain is generally not carburized, and stainless steel can be thinner, because stainless steel is soft and tough and sticky when cutting; Generally, metal pipes with a diameter greater than 20 mm and a wall thickness greater than 1.5mm will be cut continuously. At least, the opening of scissors is not that big. Even if the opening is large, there is not much shear force applied, because the levers are inclined to each other and it will slide. You can use the tap water pipe of the faucet.
Open the hook and turn the key, you can see the lock tongue, which is the part of the lock body that blocks the hook, and the steel ball with the diameter of 10 mm is reliable; Generally, the lock tongue is stamped with low carbon steel, with a thickness of less than 2 mm and a width of less than 15 mm, and the lock tongue protruding from the copper lock core is not resistant to impact.
Take a magnet to pick the lock body, and the lock body is made of iron. The thickness of the lock body tube should be greater than 2.0 mm, otherwise the pin will be weak. Those locks with embossed fonts are usually die-cast with zinc alloy, which is too fragile.
The whole copper lock body is basically not produced now, and the charge is 80 yuan/handle to 150 yuan/handle, which is quite heavy.
In reality, a better lock body is made of a whole piece of iron, and a cavity is dug in it with a milling machine or lathe, rather than a cheap product cut with a square tube or a round tube.
Originally, both the cross key and the crescent key can be used, but in fact, many locks have a small number of marbles, a small stroke range (large height difference between teeth), and even do not need spring reset. The bronze medal and material of copper lock core are poor, and the diameter of marble is small, the number of marble is small, and the height of marble is low and unreliable.
You can usually find a key with teeth on both sides, a square rod and a key with notches milled on both sides.
The key of sleeve shape also depends on the number of marbles, the height of marbles and the firmness of pins.
The best locks are original, which can improve the industrial base level of China. It is suggested to implement the national system, national competitions and competitions. I have seen some bicycle locks made by cyclists. This truly reflects the basic industrial level of the people. What is really confidential is the lock with high precision and abnormal structure made by ourselves, which is not in circulation in the market.
For example, the lock of the Beijing collider can only be opened by two people using mechanical keys at the same time, and the cockpit lock and prison lock of military aircraft are customized; The communication security machines of military, diplomatic and government departments in various countries are all designed and produced by themselves. As a sovereign country, this kind of equipment is not imported for key sectors.
I have published a paper on curbing crime in English at international academic conferences, which belongs to daily life knowledge.
Nowadays, hydraulic tongs are popular, and the common hook diameter is15 mm. When the blade of the hydraulic clamp is pressed into the hook less than half, the hook will break! ! ! Maximum opening of domestic hydraulic tongs 12 mm 360 yuan; A The maximum opening in 390 yuan is 16mm, and some openings are 14mm. Generally, the retail price of A with a maximum opening of 20mm can be one in 350 yuan, and that of imported manual hydraulic pressure is 80mm. Use hydraulic tongs in remote and dark places; Use a hard key to unscrew it in a crowded place.
The diameter of the self-made lock hook is greater than 20mm, which can be a pipe hook, or a good lock can be used. One or more steel bars are welded on the original lock hook, or the faucet iron pipe is put on. Nowadays, the blades of portable hydraulic tongs can't be opened that big. Note that the lock body and the lock hook are hinged or hinged, or the lock hook and the lock body can be separated, and there should be a hanging shielding widening reinforcement at their joint to prevent thieves from getting pliers from here. For the lock body of zinc alloy, the lock body of zinc alloy has been welded with an iron shell, the lock hook has been welded with three rebar strips with a diameter greater than 1.2mm for use in the construction site, and the keyhole has been welded with an elbow with a thickness greater than1.5mm. To unlock the lock with a key, it is necessary to rotate it from the side and extend it into the keyhole to prevent the straight rod from forcibly invading the key illegally. After being locked by a fixed object, people who stop at various occasions every day and deliver goods everywhere have experienced several years of actual combat. ! ! ! !
For the safety evaluation of the lock, the first step is to judge whether the lock core can be unscrewed by violence. After all, ordinary people cannot judge. You can enter the keyword "idle lock" online and buy this lock first. It is characterized in that a common key or screwdriver can freely rotate the lock core without opening the lock core. Then the lock body and the hook are welded and reinforced with iron pipes, steel bars and stainless steel pipes.
For the residents who live upstairs, we can see if we can make a lock hook with a tap water pipe, drill two big holes in the wall with an impact drill, put the lock hook through the other side of the wall, and lock the lock hook on the other side of the wall with a lock, but non-residents are required not to go to the other side of the wall. It should be noted that the tool for manually cutting pipes was born 50 years earlier than the hydraulic tongs. Although the lock hook made of water pipe is beautiful and neat, it should be welded with medium-diameter steel bars to prevent manual cutting of the pipe. Because the surface of water pipe is hot dip galvanized, direct welding needs to burn zinc and so on. , so it is impossible to weld. First, use an angle grinder to grind off the galvanized layer at the welding position.
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Does anyone know the principle of one key and one lock?
It's simple,
First, the manufacturing accuracy of lock cores, marbles and keys, such as the number of steps that can be subdivided in a specified stroke, that is, the difference from the highest tooth bottom to the highest tooth bottom may be 100, and the difference may be 20; No matter how high the accuracy is, it doesn't make sense. The keys of adjacent numbers are open to each other. There is little change in key tooth type (number of teeth), so it is very likely that keys with similar key tooth types will be opened to each other.
If there are two marbles, what is the arrangement and combination? What is the arrangement and combination of three marbles?
Middle school students can count. For example, each bead has 10 height levels, two beads have 100 combinations, and three beads have 1000 combinations.
One structure of those low-end bicycle locks may be hundreds of codes, that is, hundreds of keys; The structure of a high-grade lock can have hundreds of thousands of codes, that is, "numbers". For example, imported locks have high manufacturing accuracy, and each marble can have two layers; Large hollow marbles are covered with small solid marbles, and independent marbles swing by gravity to improve safety performance. Compared with the locks in Europe, America and Israel, the locks in Taiwan Province Province are less accurate.
Some low-gear bicycle locks can be opened by 70% immediately with high-strength keys, which has nothing to do with how many keys are arranged and combined in the lock design. As for the locking hook woven with steel wire, the effective diameter should be quite thick to be reliable. It is dangerous for the effective diameter to be less than 12 mm to 15 mm, and the apparent diameter cannot explain the actual effective diameter.
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Anti-theft doors and windows
We live in a bungalow, and now we want to install anti-theft doors and windows, but I don't know which one is better, stainless steel or aluminum alloy. Please analyze it if you are in trouble, thank you! ! !
If you have money, use hot-rolled solid stainless steel (exclusive, 20 yuan a kilogram) with a diameter greater than 10 mm and an oxide layer on the surface. The layman thinks it is ordinary low carbon steel and does not paint it. With 20 1 brand, the composition can be mixed and mixed, which is more difficult to cut. Mold materials can also be made of high carbon steel and alloy steel bars (there are exclusive stores), and attention should be paid to hardening when supplying. The thickness of the middle and upper and lower gaskets shall be greater than 3mm. Simple, drill a hole in the angle iron and pass through the iron bar. Specifically, it is safe to use an angle iron with a side length of 25 mm or more and a thickness of 2 mm or more as a gasket. Gaskets should be welded with iron bars. If it is high carbon steel, it will be difficult to weld and crack after welding. Unless heated in advance, the upper and lower ends of the steel bar will be lengthened.
The prices of anti-theft doors and windows of stainless steel and aluminum alloy are equivalent to the above standards, while the prices of ordinary low carbon steel are higher and the strength is lower. If you want to do it, you must first ensure that you are practical and secure.
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What equipment should be used for theft prevention?
I have an open-air courtyard with three walls. I want to install anti-theft equipment. No outsiders are allowed in!
I want to install an anti-theft device that can automatically call the police when someone passes by. What equipment should I use?
Buying stainless steel wires with a diameter of more than 0.8 mm is generally common in the specifications of 1 mm and 2 mm.
According to the environment, weave a large mesh to block possible passages.
The maximum aperture of the hole is smaller than the cross section of the human body. The exquisite method is that each intersecting longitude and latitude line is insulated from each other, and it is best to use ceramic mechanical connection and electrical insulation, or to use insulation materials that are resistant to sunlight and ultraviolet radiation and are not easy to age. Then every longitude and latitude line is interpreted by ordinary broken short circuit measuring circuit, which is a reliable anti-theft system and very reliable in the environment of heavy rain and snow hanging! ! ! ! 20 1 brand stainless steel wire will rust about one kilogram in 20 yuan, and 304 brand stainless steel wire will not rust about one kilogram in 40 yuan; Ordinary copper core wire and telephone line are all ok, but the weldability of iron wire is poor, so stainless steel is needed for gas shielded welding. The simplest method is to connect all the longitude and latitude lines in series. In the end, there are only two threads. If they are cut, they will call the police. For the advanced ones, the bridge will be used for balance interpretation, and the local short circuit will also give an alarm. Pay attention to the insulation between the nodes where latitude and longitude intersect, and tie them with insulating materials to prevent thieves from unlocking conveniently. Nail this net to the inner wall, and you can know whether someone is digging holes in the wall from the outside to steal livestock and other property. At this time, thin wires with poor mechanical strength will be used.
Self-made car theft prevention is the most reliable! ! ! ! ! ! ! !
Install alarm fireworks launch device, automatic smoke burning device and self-destruction device! ! ! ! Eject the radio into the air and send out an alarm signal.
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Is there any kind of guardrail that can prevent theft and is allowed to be installed in the property?
In many residential areas in Beijing, for the sake of beauty, it is not allowed to install anti-theft guardrail. At the same time, if the security net is installed outside, it will affect the harmony of the neighborhood and become a tool for thieves to climb! If the old security window can't be opened, and the maintenance of air conditioning is affected, is there a more humanized security window?
The net made of stainless steel wire can be curled and folded. In case of fire, the high-pressure and high-temperature jet generated by initiating explosive device is used to cut the anti-theft net, which is similar to explosive bolts. Or use electromechanical devices to open mechanical locks.
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Excuse me, what is the best intelligent anti-theft lock used on domestic household anti-theft doors without mechanical keyhole?
Design and manufacture by yourself, which is the embodiment of the real national quality, especially in the era when private individuals with ordinary wage levels can do it independently.
There is a keyhole, which provides opportunities for toothpicks, adhesives and others to destroy.
The input board and camera of fingerprint lock have poor damage resistance.
Because I have been laid off and unemployed, I can't guide students to implement it at my own expense. It's not my fault.
Relevant substantive information has been made public internally.
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The car is downstairs. It's unlocked. Who has a good idea to prevent theft?
Because there is no place to put the motorcycle battery car at home, I put it in front of my house. It's a two-story house in my own house and has been visited by thieves many times. I hate thieves now, and I can't sleep well every night. Now there is a three-wheeled motorcycle in front of my house, but there is no lock and no alarm. Who has a clever plan to guide me? ...
The easiest way to prevent your problem is to open two holes in the wall at proper positions, that is, buy a water pipe and a right-angle elbow thick enough, connect the water pipe into a ∏ shape, open a through hole at the opening position, insert the opening into the wall hole, lock the opening hole of the water pipe toward the inner wall, or insert a pin into the opening hole of the water pipe. Note that after the water pipes are assembled, the joints should be welded firmly to prevent opening, or a long pin passing through two water pipes should be inserted at the opening of the water pipes to prevent external disassembly. It can also be welded with steel bars, and the total equivalent diameter of steel bars is required to be greater than 20 mm
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Lock in the core price
Mechanical locks generally have a lock core, which can be turned with a specified key.
This kind of lock core is available in some lock factories and key repair workshops, and it has the highest versatility. Generally, the slightly better ones made in China are all made in 30 yuan, with different lengths. The invincible lock cylinder of Israel started from 300 yuan to 400 yuan, while both the lock cylinder of Israel and the lock cylinder of the United States are of full-body threaded structure, which is locked on the longitudinal groove on the outer surface with screws, and generally a lock cylinder costs more than RMB 1000.
The outer diameter of this lock core is the same, with several differences: the connecting rod driven behind the lock core and the lock core are concentric and eccentric. It is particularly important to note that the security of eccentricity is relatively higher, which enhances the resistance to thieves' hard unlocking. In addition, the length of the lock core is also different. For a long lock core with a thin door, it is necessary to use a professional thick gasket to pad the door. If you do it yourself, simply weld a thick iron ring (or several stacked rings), and the outside is longer than 10 cm. The bigger the better, the more resistant to damage and the safer the lock is. You can also pad the lock seat inside the door.
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What did Shenzhou VII fly out at the moment it opened the cabin?
Internal and external imbalance, the flow rate of the air release valve does not drop, the medium is not completely released, and the diffusion is determined by time and the cross-sectional area of the channel. Without backwashing, you need to use a vacuum pump for active exchange, which can't be done naturally in a short time. The vacuum system also needs to cascade pumps with different principles. Moreover, the porous materials, foaming materials, interlayers, thermal insulation materials and textiles in the space suit and cabin all have gas adsorption, which is not released immediately after decompression, and there is a delay. Technically speaking, the term is the diffusion rate of gas molecules, and the effective cross-sectional area of the communication hole between some cavity structures and cabin space is too small; Vacuum technology has the process of heating to remove metals and nonmetals to represent gas absorption. Electron tubes and incandescent bulbs have gas adsorbents. An electron tube is a small metal box with holes near the filament, which contains a gas adsorbent. Idiot light bulb coated with phosphorus getter on glass rod.
There are liquids in the cabin, such as sweat drops, water vapor, lubricants, grease, volatile organic compounds, fingerprints left in the process of processing and manufacturing, body fluids, etc., which evaporate rapidly in a vacuum environment and expand rapidly in volume. In the future, the cabin should be cleaned with solvent before liftoff, baked and degassed to minimize the residue of cleaning agent.
This is the reason why the hatch is forcibly opened by unknown pressure and the object flies out of the cabin, which shows the flow direction of the medium.
When the sealing rubber strip of the cabin door is under pre-pressure and one side is in vacuum environment, the gas release of the rubber strip will inevitably adhere to the airtight surface, which makes it difficult to open the cabin door after decompression. The solution is to change the opening mode of the door sealing strip from rigid integral opening displacement to flexible structure, and adopt non-planar integral displacement and non-circular local gradual displacement to open the door, which puts forward higher requirements for the design, processing and reliability of the door, and can partially establish gas microchannels to generate expansion space to reduce the difficulty, such as turning annular slots or drilling many fine holes on the annular sealing surface, and increasing the valve to release nitrogen to assist opening. In the future, these cabins will be sent to vacuum environment equipment for heating and baking before launch, so as to remove gas adsorption and pre-evaporation of evaporable substances, and increase the diameter and effective cross-section of the vent valve when the reliability and industrial basic conditions permit.
The electric energy storage shock absorber was notified to China Aerospace Department several years ago and used in astronaut seats.