Ball Lock Lever Cam Mechanism for One-Handed Operation

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Solution Overview

Problem

Existing quick-release fasteners, such as ball pins, are difficult to handle due to their bulkiness, especially in confined spaces, and require two-handed operation for locking and unlocking.

Innovation Solution

A redesigned ball pin with a compact body and ergonomic handle, featuring an anti-rotation mechanism using an oblong slot and transverse pin, and a compression spring to facilitate one-handed operation and reduced bulk, allowing the fastener to be used in tight spaces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the body length between radial openings and free end is reduced, then the bulk is reduced and it can be used in confined spaces, but the handling becomes more difficult

Engineering Contradiction:
Improvebulk of the fastenerVSAvoidhandling of the fastener
Core Design Contradiction:
Volume of moving objectVSEase of operation

Solution Approach 1:

The patent inverts the conventional sequence of operations by allowing the lever to be actuated before the body is fully inserted. The lever can be pulled to engage the ball with the cam surface during insertion, and pushed during extraction, enabling easy handling despite the compact body length. This reversal of the operational sequence resolves the contradiction between compact size and ease of operation.

Inventive Principle:
Principle #13The other way round (Inversion)

2Ease of operation

If the lever is made movable relative to the head, then one-handed operation is enabled, but the device complexity increases

Engineering Contradiction:
Improveone-handed operation capabilityVSAvoidmechanism complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The lever is designed to be movable relative to the head through a transverse axis, allowing it to pivot between locked and unlocked positions. This dynamic element enables one-handed operation by allowing the user to push or pull the lever to actuate the locking mechanism, while the anti-rotation means prevents unwanted rotation. The added complexity is minimal and justified by the significant improvement in ease of operation.

Inventive Principle:
Principle #15Dynamics

3Stability of the object's composition

If the anti-rotation means is added, then the lever rotation is controlled, but the device complexity increases

Engineering Contradiction:
Improvelever rotation controlVSAvoidmechanism complexity
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The anti-rotation means consists of an oblong slot in the lever and a transverse pin in the head, creating an asymmetric geometric constraint. The oblong slot allows linear movement of the lever relative to the head while preventing rotation. This simple asymmetric geometric feature provides effective rotation control with minimal added complexity, as it uses basic geometric shapes rather than complex mechanical constraints.

Inventive Principle:
Principle #4Asymmetry

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 solution enables easy handling and compact design, allowing the fastener to be operated with one hand and used in structures with limited space, improving usability and reducing bulkiness.

Implementation Method 1

a compression spring housed in the bore of the head

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

the lever is in contact with the handle in the unlocked position, the head comprises a bearing face intended to come into contact with a structure and a rear face disposed opposite the bearing face, the head being drilled longitudinally from the bearing face to the rear face, the cam surface bears against the rear face of the head

Methodology Applied
Scientific EffectCam mechanism: Cam

Data Source

PatentEP2863074B1Ball lock with lever
Publication Date: 2018.01.31 LISI AEROSPACE
  • EP2863074B1 patent drawingFigure 1~2
  • EP2863074B1 patent drawingFigure 3~4

AI summary

The invention relates to a quick-release ball-pin type fastener (100), comprising a tubular body (102) with a radial opening (108), an enlarged head (104), a rod (112) that can move axially within the body and through the head, a ball (110) capable of moving radially between an unlocked position where it rests in a reduced section (132) of the rod (112) inside the body, and a locked position where it protrudes radially from the body through the radial opening (108), a lever (114) pivoting about an axis (118), the lever comprising at least one cam surface (142) in contact with the head. Rotating the lever pulls the rod towards the head and brings the ball to the unlocked position.