Bi-directional Wedge Clutch Split Hub Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bi-directional clutches experience torque drag and efficiency loss due to frictional contact during transitions between free-wheel and locking modes, leading to energy dissipation.
Innovation Solution
A bi-directional wedge clutch design featuring an outer race, inner hubs, a wedge plate, and an axially displaceable activation hub, which allows for frictionless contact in free-wheel mode and non-rotatable connection in locking mode by rotating the inner hubs in opposite directions, utilizing slots and protrusions for smooth transitions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If frictional contact is maintained between components to enable transition from free-wheel mode to locking mode, then reliable mode switching is achieved, but torque drag and energy dissipation increase during free-wheel mode operation
Solution Approach 1:
The clutch is divided into two independent inner hubs (first and second inner hubs) that can rotate independently with respect to each other. This segmentation allows the clutch to achieve reliable mode switching while eliminating frictional contact during free-wheel mode, as each hub can rotate freely without dragging on the other.
Solution Approach 2:
The clutch design dynamically adjusts the engagement state of the wedge plate with the outer race based on rotational direction. During free-wheel mode, the wedge plate is disengaged from the outer race to eliminate friction. During locking mode transition, the wedge plate engages with the outer race through ramps to provide secure locking. This dynamic adjustment resolves the contradiction between reliability and energy loss.
2Stability of the object's composition
If the wedge plate maintains contact with the outer race during free-wheel mode, then structural stability is improved, but torque drag increases and efficiency decreases
Solution Approach 1:
The wedge plate's engagement state with the outer race is dynamically controlled based on operational mode. During free-wheel mode, the wedge plate is positioned to be free of contact with the outer race, eliminating torque drag while maintaining structural integrity through the hub configuration. During locking mode, the wedge plate engages with the outer race via ramps to provide stable locking. This dynamic behavior resolves the contradiction between structural stability and operational efficiency.
3Device complexity
If a single inner hub design is used, then device complexity is reduced, but the ability to achieve frictionless free-wheel mode and secure locking mode simultaneously is compromised
Solution Approach 1:
The single inner hub is segmented into two independent inner hubs that can rotate independently. This segmentation enables consistent transition between free-wheel and locking modes by allowing each hub to perform its specific function without interference from the other, thereby improving reliability while accepting increased structural complexity.
Solution Approach 2:
The wedge plate acts as an intermediary element between the two inner hubs and the outer race. It mediates the transition between free-wheel and locking modes by engaging or disengaging from the outer race based on the rotational direction, enabling consistent mode transitions while managing the complexity introduced by the dual hub design.
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 efficient torque transmission in both rotational directions with zero drag in free-wheel mode and secure locking in locking mode, enhancing operational efficiency and reducing energy loss.
Implementation Method 1
maintain some frictional contact between components of the clutch, such as the inner or outer race, and a rotationally displaceable locking element
Data Source
AI summary
A bi-directional wedge clutch, including: an outer race; first and second inner hubs; a wedge plate, radially located between the outer race and the inner hubs; and an axially displaceable activation hub engaged with the inner hubs and arranged to: for a free-wheel mode, rotate at least one of the inner hubs in a first rotational direction, with respect to the other of the inner hubs, such that the wedge plate is free of contact with the outer race; and for a locking mode, rotate the at least one of the inner hubs in a second rotational direction, opposite the first rotational direction, with respect to the other of the inner hubs, to non-rotatably connect the wedge plate with the outer race and the inner hubs.