Spindle-Nut Drive Mechanism for Excessive Load Recognition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drive devices for swinging vehicle doors or windows can be divided when excessive loads are applied, leading to obstruction of door closure and disturbance in base body movement, as they are not designed to recognize excessive loads without separation from either base body.
Innovation Solution
A drive device with a rotation regulating portion and a fragile portion that breaks under a predetermined force weaker than the nut member's breaking force, allowing the nut member to be pressed toward the drive portion, enabling recognition of excessive loads without separation from either base body, and maintaining screwing between the nut and spindle members.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a conventional drive device is used with connecting portions to allow swinging movement, then the drive device can enable base body swinging, but when excessive load is applied the drive device divides into base body side and housing side, causing obstruction and disturbance
Solution Approach 1:
The fragile portion is designed to break before the connecting portions separate, providing preliminary action that prevents the harmful division of the drive device. The fragile portion acts as a sacrificial element that fails first under excessive load, allowing the system to detect the overload condition while maintaining connection between the housing and base bodies.
Solution Approach 2:
The fragile portion serves as an intermediary element between the nut member and the connecting portions. It mediates the force transmission such that when excessive load is applied, the fragile portion breaks instead of allowing the connecting portions to separate, thus providing a detectable failure mode that maintains system integrity.
2Strength
If the drive device is designed to be strong enough to resist excessive loads, then the connecting portions remain intact, but the drive device cannot recognize excessive loads without dividing from the base body
Solution Approach 1:
The fragile portion is designed as a disposable, sacrificial element that is intentionally weaker than the connecting portions. It is designed to fail under excessive load to provide detection capability, while the main connecting portions remain intact and reusable. This allows the system to detect excessive loads through the breakage of the inexpensive fragile portion rather than through separation of the main connecting portions.
Solution Approach 2:
The fragile portion is designed with localized weakness at a specific position in the moving member. This local quality difference allows the system to have both strong connecting portions for maintaining integrity and a weak fragile portion for detection, creating different strength characteristics in different locations of the same component.
3Reliability
If a fragile portion is introduced to detect excessive loads, then excessive load recognition is enabled, but the device complexity increases
Solution Approach 1:
The fragile portion is merged into the existing moving member structure rather than being a separate component. The moving member is designed with a fragile portion as an integrated feature, combining the detection function with the existing mechanical structure. This reduces device complexity compared to adding a separate detection mechanism.
Solution Approach 2:
The fragile portion provides self-service detection of excessive loads through its own breakage. When excessive load is applied, the fragile portion breaks and this breakage itself serves as the detection signal. No additional sensors or detection systems are needed, as the fragile portion's failure mode provides the detection function automatically.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The drive device effectively recognizes excessive loads without dividing from either base body, preventing obstruction and maintaining operational integrity by suppressing nut member rotation and allowing controlled movement and closure of the door.
Implementation Method 1
a fragile portion to be broken by a predetermined force being weaker than a force required to break the nut member
Implementation Method 2
a spindle to be rotationally driven by a motor, a spindle nut to transform rotary motion of the spindle into displacement in the rotation axis direction
Data Source
AI summary
A drive device comprises a housing, a drive portion, a spindle member to rotate by driving of the drive portion, a nut member screwed with the spindle member); a moving member coupled to the nut member, and a rotation regulating portion which suppresses rotation of the nut member to move the nut member) in an axis X direction of the spindle member, wherein the moving member has a fragile portion to be broken by a predetermined force being weaker than a force required to break the nut member, and the fragile portion is configured that a fracture portion with which the nut member is pressable by the moving member toward the drive portion is formable when the fragile portion is broken.