Angled Locking Apertures for Valve Shaft Connection
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Solution Overview
Problem
Existing valve shaft connections, such as those using tapered pins or keys, often experience hysteresis and loosening under repeated cycles and higher torques, requiring precise matching and wedging for assembly, which can lead to unreliable operation.
Innovation Solution
A valve design featuring angled locking apertures and members that secure the shaft to a valve closure member, with internal pressure enhancing engagement, and a retainer for additional retention, allowing for secure rotation and minimizing the likelihood of loose connections.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If tapered pin or key connections are used to secure the shaft to the valve closure member, then the shaft connection can be assembled with simple geometry, but the connection allows hysteresis and loosens under repeated cycles and high torques
Solution Approach 1:
The connection structure is segmented into multiple locking members (typically three) distributed around the shaft circumference, each engaging with corresponding locking apertures in the valve closure member. This segmentation provides redundant locking points that prevent loosening while maintaining geometric simplicity of individual components.
Solution Approach 2:
The locking apertures are pre-formed at specific angles (typically 45 degrees) relative to the shaft axis during manufacturing. This preliminary action ensures that when locking members are inserted, they automatically engage at the correct angle to prevent both radial and axial movement, eliminating hysteresis without requiring complex adjustment mechanisms.
2Stability of the object's composition
If locked pin connections are used to secure the shaft, then the shaft position is fixed, but the pins come loose under repeated cycles and high torques
Solution Approach 1:
The locking apertures have non-uniform geometry with different sections: a first portion at a first angle (e.g., 45 degrees) for radial locking, and a second portion at a second angle (e.g., 15 degrees) for axial positioning. This local quality variation in the aperture geometry provides multi-directional stability while preventing loosening under cyclic loading and high torques.
Solution Approach 2:
The locking mechanism transitions from simple radial pin insertion to three-dimensional angular engagement. The locking members engage locking apertures that extend at angles to the shaft axis, creating stability in multiple dimensions (radial, axial, and rotational) simultaneously, which prevents loosening under complex loading conditions.
3Ease of manufacture
If tapered pin connections are used, then assembly is straightforward, but the connection requires matched sets and forcible insertion creating wedging effects
Solution Approach 1:
The locking members are designed as universal components that can be used with any shaft size within a range, eliminating the need for matched sets. The locking apertures are configured to accept standard locking members through simple insertion without forcible wedging, maintaining ease of manufacture while improving connection reliability.
4Ease of operation
If internal pressure is applied to the valve housing, then the valve operates under normal conditions, but wedged pins come loose under the pressure cycles
Solution Approach 1:
The locking mechanism is designed to be dynamic rather than static. The locking members engage with locking apertures at angles that allow the connection to adapt to pressure cycles. Internal pressure causes the valve closure member to move slightly, which tightens the engagement of the locking members in the angled apertures, improving retention rather than loosening the connection.
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 provides a secure, hysteresis-free connection that maintains engagement under pressure and torque, ensuring reliable operation and preventing loose connections, even under high internal pressures.
Implementation Method 1
internal pressure from within the valve housing increases the engagement between the locking members and the locking apertures
Data Source
AI summary
A valve having a valve closure member in a valve housing is provided. The valve closure member has a shaft received within an aperture of the closure member and extending out of the housing. One or more locking apertures are formed between an inner surface of the aperture of the valve closure member and an outer surface of the shaft, the locking apertures being angled outward from an axis of the shaft and toward the interior end of the shaft. One or more locking members are inserted into and engage each of the locking apertures, the locking members securing the position of the shaft relative to the valve closure member such that rotation of the shaft rotates the valve closure member between an open position and a closed position and such that internal pressure from within the valve housing increases the engagement between the locking members and the locking apertures.