Latching Solenoids
Latching
Permanent Magnet-Type Solenoid is a variation of the rectangular electromagnet. Utilizing the advantages of permanent magnets, its operating principle is similar to all linear solenoids; when the coil is energized, it drives the movable plunger to move into the tube. The primary advantage of a permanent magnet-type solenoid is that once energized and the plunger has moved, the plunger will remain in the energized position even after the power is turned off.
This “holding” feature is achieved because the permanent magnet creates a magnetic field that holds the plunger in place. Once energized, the power can be cut off, and the magnet is utilized to maintain the position, achieving excellent energy-saving effects. By using higher power instantaneously to generate a strong force, and then relying on the magnet for long-term holding, it prevents the coil from burning out due to overheating.
Permanent Magnet-Type Solenoid (Pull Type) Diagram
Permanent Magnet-Type Solenoid (Push Type) Diagram
High Standard Quality Control
The holding force can vary based on several factors, including the flatness and smoothness of the contact surface, and even the thickness of the metal plating. In addition to strict component material controls, Magtek implements 100% online inspection during the manufacturing process to maximize product stability. This simultaneously ensures full compliance with client requirements for both holding force upper/lower limits and release current upper/lower limits.
· 100% holding force inspection via dead weight testing
· 100% inspection of maximum and minimum release current using dedicated test fixtures
· AQL outgoing inspection utilizing automated pull force testing machines
The housing design of permanent magnet-type electromagnets can be customized into rectangular, cylindrical, or specialized shapes to match the client’s mechanical mounting configurations.
For the coil design, it can be engineered as a single-coil, dual-coil, or specialized configuration to align with specific client product applications.
| Item | Insulation Class | Coil Temperature Rise | Insulation Resistance | Dielectric Strength | Ambient Temperature Range | Lifespan |
|---|---|---|---|---|---|---|
|
MTOK Series |
Class A (105°C) |
Maximum temperature rise of 65°C under continuous energization |
100MΩ/DC 500V (at ambient temperature and humidity) |
AC 1000V, 50/60 Hz, 1 minute (at ambient temperature and humidity) |
-20°C to +40°C |
500,000 cycles or more |
Single Coil
The permanent magnet single-coil type maintains a single-coil design. When energized, current flows through the coil to generate a magnetic field and pull the plunger in. Once the motion of the plunger actuates and opens or closes the mechanical mechanism, the coil can be de-energized, and the permanent magnet will hold the plunger in the same position to achieve energy-saving functionality. When the plunger needs to reset, a reverse voltage is applied to return the plunger to its original position.
Dual Coil
The permanent magnet dual-coil solenoid utilizes two layered coils to control the pulling and releasing actions of the plunger. It typically uses three control wires, one of which serves as a common wire. The configuration consists of an inner coil and an outer coil, allowing the system to switch between pulling and releasing the plunger through these two sets of coils.
Dual-Coil Assembly (Continuous Duty)
To enable continuous duty operation, the permanent magnet dual-coil assembly incorporates a two-phase coil design. The first coil (pull-in coil) generates a sufficiently strong push or pull force under high current. Once the plunger reaches the end of its stroke, the pull-in coil is de-energized, and the second coil (holding coil) takes over to reliably maintain the plunger's position. Because the holding coil draws very little current, this dual-coil solenoid can operate under continuous electrical power for extended periods.