Medical Overtube Shape Fixing Mechanism

The overtube employs a dynamic structure that can switch between flexible and rigid states. The nested annular members are designed to be movable relative to each other, allowing the tube to be flexible during insertion and then lock into a rigid, shape-maintaining configuration once deployed. This dynamic transition resolves the contradiction between needing flexibility for insertion and rigidity for shape stability.

The overtube is divided into multiple nested annular members that can move independently. This segmentation allows each member to contribute to flexibility during insertion, while the collective interaction between members through frictional forces enables shape locking when deployed. The segmented structure thus simultaneously provides ease of insertion and shape stability.

The overtube transitions from a flexible, deformable state during insertion to a rigid, shape-fixed state during device insertion. This dynamic state change ensures the tube can adapt to body cavities initially, then maintain a fixed shape to prevent tissue load when the medical device is being inserted, thus resolving the contradiction between deformation capability and patient safety.

The overtube is inserted in a flexible, deformable state to navigate the body cavity, and only after proper positioning does it transition to the shape-fixed state. This preliminary deformation action allows the tube to reach the target location without causing tissue load, and then it locks into place to prevent deformation during subsequent medical device insertion.

A gate mechanism acts as an intermediary between the channel and the external environment. This gate can be controlled to open or close the channel, allowing medical devices to pass only when intended. The gate mechanism thus mediates between the need for easy device passage and the need to prevent premature or accidental insertion, improving both ease of operation and reliability.

The gate mechanism is integrated with the overtube's shape-fixing mechanism, so that the channel automatically opens or closes in response to the overtube's state changes. This self-service approach ensures the channel control is reliably linked to the overtube's functional state, reducing the risk of premature insertion while maintaining ease of device passage when appropriate.