Rotary Impact Tool Phase-Based Torque Control

The patent segments the screw fixing process into two distinct phases: internal thread formation (where impact is beneficial and motor speed should be maintained) and tightening (where impact control is needed and motor speed should be reduced). This segmentation allows the system to apply different control strategies to different operational phases, resolving the contradiction by enabling high-speed operation during thread formation while still providing impact protection during tightening.

The patent implements dynamic control of motor rotation speed based on the operational phase and impact detection. During internal thread formation, the motor operates at high speed regardless of impact detection. During tightening, the motor speed is reduced when impact is detected. This dynamic adjustment of operational parameters resolves the contradiction by adapting the control strategy to the specific operational context.

The patent divides the screw fixing operation into distinct phases (internal thread formation and tightening) and applies different control strategies to each. During internal thread formation, the system maintains high motor speed to maximize productivity, as impact forces are beneficial for thread creation. During tightening, the system reduces motor speed when impact is detected to prevent screw head damage. This phase-based segmentation resolves the contradiction by enabling high productivity during thread formation while still providing protection during tightening.

The patent maintains continuous high-speed motor operation during the internal thread formation phase, even when impact is detected, because the impact is useful for forming threads. This continuous useful action maximizes productivity during the thread formation phase. The system only reduces speed during the tightening phase when impact becomes harmful, thus maintaining productivity overall while preventing damage.