How does the SM39 Absolute encoder achieve long-term memory and accumulation of multi-turn position information in a battery-free mechanical design?
Release Time : 2026-06-29
In industrial automation and precision motion control, the SM39 Absolute encoder is widely used because it retains absolute position information even after power failure. Especially in battery-free designs, the device must not only achieve high reliability but also avoid the lifespan limitations and maintenance costs associated with traditional batteries.
1. Mechanical Counting Structure for Multi-Turn Accumulation
In battery-free designs, multi-turn information is typically based on a purely mechanical or mechanically coupled counting structure. For example, a multi-stage gear reduction system progressively transmits the number of shaft rotations to a low-speed counting unit. Each rotation of the input shaft corresponds to a proportional rotation of the internal gear set, accumulating the number of rotations. This structure relies on mechanical position latching; even without power, the gear positions remain unchanged, thus achieving physical memory of multi-turn information.
2. Absolute Encoder Disk and Position Information Mapping
In addition to the mechanical counting component, the SM39 Absolute encoder typically incorporates an absolute encoder disk to record high-resolution positions within a single turn. The encoder disk converts position into a unique digital code through photoelectric or magnetic induction. When combined with a multi-turn counting structure, each single-turn position forms a unique combination with the current turn number, thus constituting a complete multi-turn absolute position system. This structure ensures that the system can accurately restore the current spatial position after restarting at any time.
3. Implementation Methods of Non-Battery Memory Mechanisms
To avoid using batteries, some high-end multi-turn encoders employ magnetic holding structures or self-powered technology. For example, a mechanical transmission gear combined with a magnetic encoder maintains the turn number information by relying on the magnetic state in the event of a power outage; or a miniature energy harvesting element is used to obtain a small amount of energy during shaft movement to update the turn number register state. The core idea of this type of design is "update as it moves, do not lose data when power is off," replacing the role of electrical memory at the structural level.
4. Mechanisms for Ensuring Shock Resistance and Long-Term Stability
Since multi-turn information relies on mechanical or magnetic structures for retention, vibration and shock resistance are particularly critical. Engineering designs typically employ high-strength metal gears, preloaded bearings, and sealing structures to reduce mechanical backlash and wear. Meanwhile, by optimizing coding redundancy and error verification mechanisms, it ensures that no rotation errors will occur due to the accumulation of minute displacements during long-term operation. This allows the battery-free SM39 Absolute encoder to maintain long-term stability and high reliability in industrial environments.
Overall, the battery-free SM39 Absolute encoder, through the synergy of mechanical counting, absolute coding, and structural preservation, achieves the ability to retain position information for extended periods without external power, providing a stable core sensing foundation for highly reliable industrial systems.
1. Mechanical Counting Structure for Multi-Turn Accumulation
In battery-free designs, multi-turn information is typically based on a purely mechanical or mechanically coupled counting structure. For example, a multi-stage gear reduction system progressively transmits the number of shaft rotations to a low-speed counting unit. Each rotation of the input shaft corresponds to a proportional rotation of the internal gear set, accumulating the number of rotations. This structure relies on mechanical position latching; even without power, the gear positions remain unchanged, thus achieving physical memory of multi-turn information.
2. Absolute Encoder Disk and Position Information Mapping
In addition to the mechanical counting component, the SM39 Absolute encoder typically incorporates an absolute encoder disk to record high-resolution positions within a single turn. The encoder disk converts position into a unique digital code through photoelectric or magnetic induction. When combined with a multi-turn counting structure, each single-turn position forms a unique combination with the current turn number, thus constituting a complete multi-turn absolute position system. This structure ensures that the system can accurately restore the current spatial position after restarting at any time.
3. Implementation Methods of Non-Battery Memory Mechanisms
To avoid using batteries, some high-end multi-turn encoders employ magnetic holding structures or self-powered technology. For example, a mechanical transmission gear combined with a magnetic encoder maintains the turn number information by relying on the magnetic state in the event of a power outage; or a miniature energy harvesting element is used to obtain a small amount of energy during shaft movement to update the turn number register state. The core idea of this type of design is "update as it moves, do not lose data when power is off," replacing the role of electrical memory at the structural level.
4. Mechanisms for Ensuring Shock Resistance and Long-Term Stability
Since multi-turn information relies on mechanical or magnetic structures for retention, vibration and shock resistance are particularly critical. Engineering designs typically employ high-strength metal gears, preloaded bearings, and sealing structures to reduce mechanical backlash and wear. Meanwhile, by optimizing coding redundancy and error verification mechanisms, it ensures that no rotation errors will occur due to the accumulation of minute displacements during long-term operation. This allows the battery-free SM39 Absolute encoder to maintain long-term stability and high reliability in industrial environments.
Overall, the battery-free SM39 Absolute encoder, through the synergy of mechanical counting, absolute coding, and structural preservation, achieves the ability to retain position information for extended periods without external power, providing a stable core sensing foundation for highly reliable industrial systems.