Rotatable Lid Damper Regulates Opening Speed

The patent applies dynamics by making the damping force adjustable during the opening motion. The damper structure transitions from providing resistance to allowing free motion based on the lid part's position, enabling controlled opening speed that prevents toppling while maintaining ease of operation. The movable stopper and movable groove create a dynamic system where the damping characteristic changes throughout the opening sequence.

The patent changes the damping parameter dynamically during the opening process. Initially, the damper provides resistance to control opening speed and prevent toppling. As the lid part reaches a predetermined position, the parameter changes to allow free motion, enabling the lid to open completely without restriction. This parameter change resolves the contradiction between controlled opening and ease of operation.

The patent merges multiple regulatory functions into a single integrated damper structure. The movable stopper, movable groove, and biasing spring work together as one unified mechanism that provides both damping control and position-dependent motion control. This merging approach achieves stability during opening without proportionally increasing device complexity, as the components are functionally integrated rather than separate sequential regulators.

The patent segments the opening motion into distinct phases: an initial phase with damping control and a subsequent phase with free motion. The movable stopper and movable groove create spatial segmentation of the opening trajectory, with each segment having different control characteristics. This segmentation allows the system to achieve stability during the critical initial phase while maintaining simplicity through the unified damper structure design.