Search results
Results from the WOW.Com Content Network
An electric current typically energizes the electromagnet to attract and hold the steel plate, keeping the door open. Unlike electromagnetic locks, the magnetic attraction of an electromagnetic door holder is usually weak enough that it can be manually overpowered at any time by anyone, allowing the door to close. [citation needed]
The principle behind an electromagnetic lock is the use of electromagnetism to lock a door when energized. The holding force should be collinear with the load, and the lock and armature plate should be face-to-face to achieve optimal operation. The magnetic lock relies upon some of the basic concepts of electromagnetism.
The other iron U will see exactly the opposite. In this way almost all the magnetic flux will be concentrated inside both iron U's creating a close circuit for the magnetic field (because the high permeability of the iron). Having all the flux confined inside the structure, the magnetic flux outside became almost nonexistent.
A magnetic keyed padlock A magnetic keyed padlock. A magnetic keyed lock or magnetic-coded lock is a locking mechanism whereby the key utilizes magnets as part of the locking and unlocking mechanism. Magnetic-coded locks encompass knob locks, cylinder locks, lever locks, and deadbolt locks as well as applications in other security devices.
The card stores a physical or digital pattern that the door mechanism accepts before disengaging the lock. There are several common types of keycards in use, including the mechanical holecard, barcode , magnetic stripe , Wiegand wire embedded cards, smart card (embedded with a read/write electronic microchip ), RFID , and NFC proximity cards.
A door chain, security chain, or security door chain or chain door interviewer [1] consists of a small chain attached to the door frame, which attaches to a track on the door for security purposes. It is a type of lock that is often used along with other types of locks to secure a door. [ 2 ]
"Soft" magnetic materials with low coercivity and hysteresis, such as silicon steel, or ferrite, are usually used in cores. Magnetic field (green) created by a current-carrying winding (red) in a typical magnetic core transformer or inductor, with the iron core C forming a closed loop, possibly with air gaps G in it. The drawing shows a section ...
A "horseshoe magnet" made of Alnico 5, about 1 inch high.The metal bar (bottom) is a keeper. A magnet keeper, also known historically as an armature, is a bar made from magnetically soft iron or steel, which is placed across the poles of a permanent magnet to help preserve the strength of the magnet by completing the magnetic circuit; it is important for magnets that have low magnetic ...