The specific classification of electronic locks First, the cable lock According to the input password method, it can be divided into the following categories: 1, button type Use the keyboard (or combination button) to enter the unlock password, which is convenient to operate. Internal control circuits often use an electronic lock ASIC. The password preset is changed by changing the keyboard (or combination button) to the internal control circuit. Usually the computer memory password can reach more than 10,000 groups, and the number can be changed and combined at will. An alarm can also be set. Such locks are mostly used by security doors and anti-theft safes. 2, dial type Use the mechanical dial switch to enter the unlock code. Many push-button electronic locks can be converted into dial-type electronic locks. If the number is dialed incorrectly, the alarm circuit will automatically turn on and signal. However, this kind of lock is not as fast as the button type when it is opened. 3, electronic key type Use the electronic key to enter (or as) the unlock password. The electronic key is an important part of the control circuit. The electronic key can be composed of a component or a unit circuit composed of components, and is formed into a small handheld unit. The connection between the electronic key and the main control circuit can be various forms such as sound, light, and electromagnetic. The electronic key is an important part of the control circuit. The electronic key can be composed of a component or a unit circuit composed of components, and is formed into a small handheld unit. The connection between the electronic key and the main control circuit can be in various forms such as sound, light, electricity, magnetism and microwave. According to US Patent 4,786,900. The electronic key of this lock is assembled with an electronic watch or solar calculator. When unlocking, you must operate the buttons on the watch calculator to give the corresponding project name (such as valuables, door, box, car, office), password and password data. The optical signal corresponding to the name code, password and password is then output from an LED on the electronic key, sent to the keyhole, and converted into an electrical signal. These name codes, passwords and passwords are pre-stored in the memory of the electronic lock. The corresponding electronic lock can only be opened if the newly sent name code, password and password code are identical to the contents of the memory. 4, touch The touch method is used to input the unlock password, which is easy to operate. Compared with the push button switch, the touch switch has a long service life and low cost, so the electronic lock control circuit is optimized. The password is entered by using the bimetal touch point, which is concealed and has strong confidentiality. There is a pseudo key lock 5S function that can drive the alarm. Adopting CMDS circuit, the micro power consumption is strong. Second, password identification electronic lock This electronic lock controls the opening and closing of the lock by verifying the correctness of the input password. It has system self-locking and automatic alarm function when the input password is incorrectly exceeded. The input method of the password can be divided into two types: keyboard input and remote input. The keyboard type electronic lock mainly uses the keyboard to input the electronic lock password, and the electronic lock controller judges whether to open the door by comparing the customer password stored therein. It has the advantages of convenient operation, no need to carry cards, and low cost. However, it also has defects such as easy password leakage, no access records, and only one-way control. The remote control electronic lock uses a set of codec chips for remote transmission of password information. Different password locks adopt different port setting modes in the hardware circuit design, even if the remote controllers of the same chipset cannot be shared. Although this improves the security of the lock a lot, it also has signal coding that is easily intercepted by the space, the remote control method is easily interfered by the obstruction, and the remote control is lost and cannot be unlocked. Third, the card identification type electronic lock The card identification type electronic lock uses various types of cards (including a magnetic card, an IC card, etc.) as a code carrier, and controls the electronic lock through a corresponding card reader reading method. Magnetic card type electronic lock After the magnetic card is inserted into the card reader, the card reader reads the information in the magnetic strip and sends it to the electronic lock controller. The controller performs functions such as judging, executing, and recording according to the law. The magnetic card type electronic lock has lower cost, one person and one card, and is convenient to use. The microcomputer can record the opening event, but the magnetic card and the card reader are worn out, the life is short, and the magnetic card is easily copied, and the information in the card is susceptible to the external magnetic field. Interference, security is average. The working principle of the IC card type electronic lock is basically the same as that of the magnetic card type electronic lock, but since the IC card is not magnetized, especially the non-contact type IC card has no contact with the reading and writing device, and has a long service life, and can realize two-way control, card More difficult to copy, higher security. Fourth, biometric electronic lock The biometric electronic lock uses the biometric characteristics of the human body as a password input, and the identification and control of the electronic lock is controlled by the recognizer. Studies have shown that human fingerprints, palm prints, faces, pronunciation, iris, retina, etc. have the characteristics of uniqueness and stability, that is, each of these characteristics is different from others and remains unchanged for life. The identity is identified. Based on these characteristics of human beings, intelligent electronic locks with various biometric methods such as fingerprint recognition, facial recognition, and iris recognition have emerged. Because these biometric features have the advantage that other media cannot be replaced, the intelligent electronic lock based on this has excellent security and high reliability, but the cost is high and the environment requirements are high. Therefore, the application rate is relatively low in a small intelligent electronic lock system. Five, wireless locks Non-door lock electronic locks can be mainly used in transportation and transportation, warehousing, fresh milk transport vehicles, cash transport vehicles, refrigerated trucks, pharmaceutical transportation, tobacco transportation and other transportation fields. It is mainly used for transportation vehicle doors, special vehicle manhole covers and warehouse doors to ensure the safety of goods transported or guarded and to prevent theft. The electronic lock adopts a mechanical lock body combined with the Internet of Things related technology, and the lock body has a built-in wireless transceiver module. When the lock body is opened and closed, the wireless transceiver module transmits the open and close lock signals to the monitoring host remotely. If the unlock signal received by the monitoring host appears in the abnormal time period, the signal is judged as the stolen and beaconed signal, and the monitoring host immediately generates an alarm message, so that the relevant personnel can timely deal with it to prevent financial loss. Editor in charge: Zhou Jiao
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