Torque-Limiting Coupler With Elastic Slip for Motor Shaft Overload
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric motor shafts in vehicles often apply excessive torque to camshaft phasers, causing stress and misalignment issues due to rigid connections, which can lead to damage and wear when the torque limit is exceeded.
Innovation Solution
A torque-limiting coupler system that includes an elastic member and a rigid frame, allowing the coupler to maintain a fixed relationship between the electric motor's output shaft and the vehicle's rotatable input until a predetermined torque limit is reached, at which point it permits angular displacement to prevent excessive torque transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a rigid connection is used between the electric motor output shaft and the rotatable input, then the torque transmission is efficient and reliable, but excessive torque causes stress and damage to components when the torque limit is exceeded
Solution Approach 1:
The coupling mechanism changes its physical state from rigid to flexible based on the torque parameter. When torque exceeds the predetermined limit, the elastic member deforms, changing the coupling parameter from fixed angular relationship to variable angular relationship, thereby limiting the transmitted torque and protecting components from excessive stress
Solution Approach 2:
The coupler transitions from a static rigid connection to a dynamic flexible connection. The elastic member allows the system to adapt its stiffness dynamically - maintaining rigidity under normal operating conditions for efficient torque transmission, and becoming flexible when torque exceeds the limit to prevent damage
2Manufacturing precision
If a rigid connection is used between the electric motor output shaft and the rotatable input, then the angular position relationship is fixed and precise, but misalignment between the output shaft and rotatable input causes stress and wear
Solution Approach 1:
The coupling mechanism changes its physical state from rigid to flexible based on the torque parameter. When torque exceeds the predetermined limit, the elastic member deforms, changing the coupling parameter from fixed angular relationship to variable angular relationship, thereby limiting the transmitted torque and protecting components from excessive stress
Solution Approach 2:
The elastic member acts as a flexible element that can deform to accommodate misalignment between the output shaft and rotatable input. This flexibility allows the system to absorb angular deviations without transmitting excessive stress to the components, while still maintaining precise angular position control under normal operating conditions
3Adaptability or versatility
If the camshaft phaser reaches an end of the range with stops, then the timing adjustment is limited, but a relatively large amount of torque is applied to the camshaft phaser causing unwanted stress
Solution Approach 1:
The elastic member serves as a pre-configured cushioning element that engages before excessive torque can be transmitted to the camshaft phaser. When the phaser reaches its timing range limits and encounters stops, the elastic member deforms to absorb the torque spike, preventing direct transmission of harmful forces to the phaser components
Solution Approach 2:
The coupling mechanism changes its physical state from rigid to flexible based on the torque parameter. When torque exceeds the predetermined limit, the elastic member deforms, changing the coupling parameter from fixed angular relationship to variable angular relationship, thereby limiting the transmitted torque and protecting components from excessive stress
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 torque-limiting coupler effectively limits the torque applied to the rotatable input, reducing stress and wear on components by allowing the output shaft to rotate independently when the torque limit is exceeded, thus protecting the motor and mechanical device from damage.
Implementation Method 1
an elastic member, configured to engage the other of the rotatable input or the output shaft of the electric motor, that engages the rigid frame such that the elastic member substantially maintains its shape and inhibits angular displacement between the rotatable input and the output shaft when an amount of torque received from the output shaft is below a predetermined torque limit, the elastic member changes shape permitting angular displacement between the rotatable input and the output shaft when an amount of torque received from the output shaft exceeds the predetermined torque limit
Data Source
AI summary
A torque-limiting coupler for connecting an electric motor to a rotatable input of a vehicle is provided, including: a rigid frame that is configured to be coupled to one of the rotatable input or an output shaft of the electric motor; and an clastic member, configured to engage the other of the rotatable input or the output shaft of the electric motor, that engages the rigid frame such that the elastic member substantially maintains its shape and inhibits angular displacement between the rotatable input and the output shaft when an amount of torque received from the output shaft is below a predetermined torque limit, the elastic member changes shape permitting angular displacement between the rotatable input and the output shaft when an amount of torque received from the output shaft exceeds the predetermined torque limit.