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 there is a high probability 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. The key quantity of lock safety performance evaluation index is design accuracy, and the mutual opening rate reflects the actual machining accuracy.
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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 line 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 can give me some advice? ...
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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Some Problems about Invisible security window
1. The gap between steel wires is several centimeters. Can thieves come in without breaking the wire?
My home is on the second floor (the first floor is the garage). Is it suitable to install invisible anti-theft net?
3. Is the stealth anti-theft net 100% safe? Do thieves really sigh at the invisible anti-theft net?
Of course, security window, this strong thing is reliable. You spend money on electronic waste, which is not as trustworthy as traditional steel bars. If you have money, go to the mold material supplier to buy all kinds of mold steel bars. There are many materials and heat treatment effects that even hydraulic tongs can't stop cutting! ! ! ! ! ! ! Both the Yangtze River Delta and the Pearl River Delta (such as Dongguan) are heavily supplied. Your opponent is a hydraulic clamp.
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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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Family anti-theft
My house is always being stolen ~ ~ either locked or the door smashed. Report it to the police. Now the police do nothing unless they pay money. . . . . . It's farmers who don't care at all. I went out to work yesterday. I came back at night and found that the computer should not have been stolen. Call the police. The police asked me for a receipt, and I bought a computer without a receipt, so the police left it alone. I am sad. My house has been stolen four times. I have to go out to work. I can't watch it at home all day. So I want to install a monitor like that on TV, but I don't understand. What should I say? What to buy? What's the name of that monitor? Can you help me? Hey, the world is crazy. I want to install one of these things at home. Who can help me? thank you
I am a farmer's child, and I don't have much money at home just to fight for breath. I hope everyone will consider my financial situation and give me a suitable monitor, as long as it can record everything during the day, and it is best to be small and hidden. Thank you. I'm about to cry. Why didn't anyone give me a satisfactory answer?
Dig a cellar to bury the treasure while you are away. The standard saying is, be clear.
Or dig a tunnel under the police station and build a storage room to connect with the police station.
Or dig right in front of the police station. All burglar alarms, cameras, security guards, renting warehouses and renting bank safes are exempted. The security of locks, door locks and security doors is based on the time of dismantling, which is much stronger than them.
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The wall is a hollow brick, how can the expansion bolt be stressed?
I installed an invisible anti-theft net, which often touched the hollow brick wall, but the M6*80 expansion bolt was still loose after it was driven in. I wonder if there is any good way.
Grouting! ! ! ! ! ! ! !
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About impersonating security window.
The baby can already walk, and the window at home is quite low. It's impossible to watch him 24 hours a day for fear that he will climb the window. Do you think it is necessary to install security window?
Life is the most precious! ! ! ! ! ! ! ! !
First, use nylon rope as a net, multi-level, in order to prevent the metal wire from hurting the baby, it is easy to use a metal net with a small metal wire diameter.