Dielectric Cam Shaft Assembly for Insulated Ball Valve Torque Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In actuated ball valve systems, particularly in aircraft water supply systems, there is a need for a dielectric barrier to prevent electrical faults from the motor end from being transmitted to the metal ball shaft, while maintaining torque transmission, especially when the ball shaft experiences resistance or is jammed, and to avoid damage from water exposure.
Innovation Solution
A torque transfer assembly featuring a dielectric cam shaft made of non-conductive material, interfacing with a motor shaft and a ball shaft through a bushing with multiple points of contact, distributing loads and torque, and using a shear pin for secure rotation, ensuring insulation and reliable torque transfer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a metal shaft is used to transmit torque from the motor to the ball shaft, then torque transmission is reliable, but electrical faults from the motor can be transmitted to the ball shaft
Solution Approach 1:
A dielectric material is introduced as an intermediary component between the motor shaft and the ball shaft. This dielectric material provides electrical insulation to prevent fault transmission while still allowing mechanical torque to be transmitted through it, thus resolving the contradiction between electrical safety and power transmission.
Solution Approach 2:
The shaft assembly uses composite construction with dielectric material forming part of the torque transmission path. The dielectric material is combined with metal components to create a hybrid structure that provides both electrical insulation and sufficient mechanical strength for torque transmission.
2Reliability
If a dielectric barrier is introduced between the motor shaft and ball shaft, then electrical fault prevention is improved, but torque transmission capability may be reduced
Solution Approach 1:
The dielectric shaft is designed as a composite structure that combines insulating material with sufficient mechanical strength. The material selection and structural design ensure that the dielectric barrier does not compromise the torque transmission capacity required for reliable valve operation.
Solution Approach 2:
The design adjusts parameters such as the dielectric material's mechanical properties, shaft diameter, and engagement features to optimize both electrical insulation performance and torque transmission capability, ensuring neither function is compromised.
3Strength
If the ball shaft is made of metal for durability, then it can withstand mechanical loads, but it becomes vulnerable to electrical faults from the motor
Solution Approach 1:
The dielectric material serves as a protective intermediary between the metal ball shaft and the motor, allowing the ball shaft to maintain its metal construction for mechanical durability while preventing electrical faults from reaching it.
Solution Approach 2:
The electrical conductivity is extracted from the torque transmission path by removing the direct metal-to-metal connection between the motor shaft and ball shaft, while the mechanical strength function is preserved through the dielectric material and engagement features.
4Power
If direct metal-to-metal contact is used between drive components, then torque transmission is efficient, but water can cause corrosion and electrical faults
Solution Approach 1:
The dielectric material acts as an intermediary that replaces direct metal-to-metal contact, preventing water-induced corrosion and electrical faults while maintaining sufficient torque transmission efficiency through its mechanical engagement features.
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 dielectric cam shaft effectively prevents electrical faults from reaching the ball shaft, maintains torque transmission even under resistance, and protects against water damage, ensuring reliable operation and durability in wet environments.
Implementation Method 1
the cam shaft is formed of a dielectric material defining an insulating barrier between the drive and the driven shaft
Implementation Method 2
A shear pin may be provided through aligned bores in the bushing and the motor shaft to rotatable connect these components and transfer torque
Data Source
Figure 1
Figure 2
Figure 3A~4B
AI summary
According to the disclosure, there is provided a torque transfer assembly comprising a drive shaft (2) and a driven shaft (10), the drive shaft comprising a motor shaft configured to be connected to and rotated by a motor, and a cam shaft (4) connected to and rotatable with the motor shaft, the driven shaft being connected to and rotatable with the cam shaft, and wherein the cam shaft is formed of a dielectric material defining an insulating barrier between the drive and the driven shaft.