How to choose the appropriate locking tongue?
The locking tongue, which may seem insignificant on smart locks, actually contains many benefits and has a significant impact on the performance of smart locks.
The locking tongue is the component in a lock that directly plays a locking role and is the ultimate executor of the entire door lock system. The recognition module, lock body, lock cylinder and other components have been busy for half a day, in order to make the lock tongue open and close as needed. So it is necessary to have a comprehensive understanding of the types of locking tongues and choose the appropriate one to use.
Locking tongue length
The national mandatory standard GB 21556-2008 "General Technical Conditions for Safety of Locks" has mandatory provisions that the length of the locking tongue of Class A locks must be greater than or equal to 20 millimeters. This requirement is relatively easy to implement, as a two centimeter long locking tongue is not a difficult task in production.
Locking tongue material
As an important load-bearing component, the locking tongue has high requirements for the firmness of the material. According to the mandatory national standard GB 21556-2008 "General Technical Conditions for Safety of Locks", the axial static load of the A-level lock tongue must be greater than 3000 N, and the lateral static load of the lock tongue must be greater than 6000 N. It can be seen that as long as the A-level lock meets the national standard, its lock tongue strength is very high.
On May 5, 2020, the China Consumer Association, Sichuan Provincial Consumer Committee, Foshan Municipal Consumer Committee, and Shenzhen Municipal Consumer Committee jointly released a comparative test report on smart door locks. A total of 29 sample locks were selected, and the lock tongue length of all sample locks met the requirement of 20 millimeters or more, but only 12 sample locks met the requirement for lock tongue strength. It can be seen that when selecting smart locks, paying attention to the strength and material of the lock tongue is a very important standard.
Common locking tongue materials include zinc alloy, stainless steel, etc. Zinc alloy has advantages such as easy processing, easy forming, and mature processing technology, while stainless steel has advantages such as high strength, less deformation due to impact, corrosion resistance, and high temperature resistance. Considering the high strength requirements of locking tongues, most of the locking tongues of well-known brands are made of stainless steel material.
Locking tongue shape
The locking tongue on the market has various shapes such as square tongue, oblique tongue, cylindrical tongue, hook tongue, crab claw tongue, etc. Among them, ordinary slanted tongues are equipped with springs, and criminals can easily push the slanted tongue back with a card to achieve the purpose of unlocking, which is a concern for safety performance. Once the owner forgets to lock the door and relies solely on the diagonal tongue for theft prevention, it will greatly increase the risk of encountering burglary.
In contrast, square and cylindrical tongues do not have spring components and will not retract due to external forces such as card compression, thus greatly increasing the safety index.
In addition, some brands of smart locks adopt specially constructed locking tongues, such as self popping locking tongues, flipping inclined tongues, anti tampering small locking tongues, reverse locking tongues, and other designs.
Taking reverse locking tongue as an example, for door locks equipped with reverse locking tongue, the locking tongue cannot be pressed down from one side. Only when the lock body is opened can the locking tongue in both directions be opened from the inside. These designs can more effectively prevent small cards from unlocking.
Number of locking tongues
The number of locking tongues may vary depending on the lock body, and can be divided into single locking tongues and multiple locking tongues. Compared to a single locking tongue, when multiple locking tongues are violently opened, prying open one locking tongue will not cause a fatal blow to the anti-theft function. Smart locks from well-known brands often use three or more locking tongues, which can more effectively resist violent unlocking behavior.
Although the locking tongue is small, it is also an important component of smart locks. Poor quality locking tongues can have a significant adverse impact on the performance of the lock body. Choose a smart lock with a high-quality tongue to better enjoy a smart new life.
*Originally from Intelligent Door Lock Research Pro, if involved in copyright issues, please contact us for prompt deletion.