Rotationally Locked Forceps Shafts With Jaw Over-Travel Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional medical devices, such as forceps, face challenges in reducing packaging space, simplifying design and manufacturing, enhancing user experience, increasing stability, and preventing damage during use.
Innovation Solution
The development of a medical device with a handpiece that includes a rotatable, openable, and closeable end effector, featuring a drive shaft motion transfer assembly with a rotational actuator and a force-limiting mechanism to prevent over-travel and protect the jaws from damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If conventional forceps design is used, then manufacturing and packaging are straightforward, but packaging space is excessive and design complexity cannot be reduced
Solution Approach 1:
The drive shaft is rotatably received within the outer shaft, creating a nested configuration where one shaft is housed inside another. This nesting arrangement reduces the overall volume of the forceps device, allowing for more compact packaging while maintaining the functional independence of each shaft component.
Solution Approach 2:
The motion transfer assembly serves multiple functions: it transfers rotational motion from the handpiece to the end effector, provides rotational locking between shafts, and enables independent rotation of the outer shaft relative to the drive shaft. This multi-functionality reduces the need for separate components, simplifying design while reducing packaging space.
2Ease of operation
If the outer shaft is allowed to rotate independently, then user experience and operational flexibility are improved, but stability and potential for damage increase
Solution Approach 1:
The force-limiting mechanism dynamically adjusts the interaction between the outer shaft and drive shaft. During normal operation, the outer shaft can rotate independently for flexibility. When excessive force is detected, the mechanism engages to provide rotational locking, preventing damage while maintaining operational flexibility throughout the range of motion.
Solution Approach 2:
The force-limiting mechanism is pre-configured to prevent over-rotation and excessive forces before they can cause damage. By establishing these protective constraints in advance, the system maintains stability and reliability while still allowing the outer shaft to rotate independently within safe operational parameters.
3Reliability
If rotational locking is implemented between shafts, then stability is increased, but device complexity and manufacturing difficulty increase
Solution Approach 1:
The rotational locking function is merged with the motion transfer mechanism itself. The same interface that transfers rotational motion from the handpiece to the end effector also provides the locking capability between the outer shaft and drive shaft. This integration eliminates the need for separate locking components, reducing manufacturing complexity while maintaining stability.
4Object-affected harmful factors
If a force-limiting mechanism is added, then damage prevention is improved, but device complexity increases
Solution Approach 1:
The force-limiting mechanism is merged with the rotational interface between the outer shaft and drive shaft. The same mechanical interaction that enables motion transfer and rotational locking also provides the force-limiting function. This multi-functional integration prevents damage without adding separate complex mechanisms, thereby limiting the increase in device complexity.
Data Source
AI summary
Medical devices, such as forceps including a handpiece having a housing and an inner shaft that extends out of the handpiece along a longitudinal axis to transfer motion to an end effector. The inner shaft being rotatable with respect to the handpiece. An outer shaft that is rotatable with respect to the housing is loated around the inner shaft. The medical device further including an end effector coupled to the inner shaft and the outer shaft. The outer shaft rotationally constrained to the inner shaft at a first longitudinal location and at a second longitudinal location.