Spindle Motor Bushing for Shaft Coupling Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Miniaturization and slimming of spindle motors have led to a reduction in the length of their rotation shafts, resulting in a weakened coupling area between the rotation shaft and the rotor yoke, causing the rotor yoke to disengage from the rotation shaft when disks are mounted or removed.
Innovation Solution
A spindle motor design that includes a bushing coupled to the rotation shaft and a rotor yoke, increasing the coupling area and strength by using a press-fitted bushing to enhance the coupling between the rotation shaft and the rotor yoke, with a clamp and rubber liner to prevent disengagement and slippage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the rotation shaft is shortened to achieve miniaturization and slimming, then the size of the spindle motor is reduced, but the coupling area between the rotation shaft and rotor yoke is reduced, weakening the coupled strength
Solution Approach 1:
A bushing is introduced as an intermediary component between the rotation shaft and rotor yoke. The bushing is press-fitted onto the rotation shaft and receives the rotor yoke, thereby mediating the connection between these two components. This intermediary structure increases the coupling area and strength without requiring a longer rotation shaft, resolving the contradiction between miniaturization and coupling strength.
2Volume of moving object
If the rotation shaft is shortened, then the motor becomes more compact, but the rotor yoke is prone to disengage from the rotation shaft during disk mounting and removal
Solution Approach 1:
The bushing serves as a mediator that prevents direct contact between the rotor yoke and rotation shaft. By press-fitting the bushing onto the rotation shaft and having the rotor yoke interact with the bushing, the connection is stabilized, preventing disengagement during disk mounting and removal operations while maintaining compact dimensions.
3Volume of moving object
If the coupling area is reduced due to shorter rotation shaft, then the motor achieves miniaturization, but the friction and stability during disk operation are compromised
Solution Approach 1:
Instead of increasing the length of the rotation shaft (one dimension), the bushing introduces additional coupling surfaces in radial and axial directions. The bushing's outer surface contacts the rotor yoke while its inner surface is press-fitted to the rotation shaft, creating multiple contact areas that distribute forces and enhance stability without increasing the overall motor size.
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 design maintains the strength of the coupling between the rotor yoke and rotation shaft even with short rotation shafts, improving product reliability by preventing disengagement and enhancing disk alignment and friction prevention.
Implementation Method 1
a bushing coupled to the rotation shaft
Data Source
AI summary
A spindle motor is provided. The spindle motor includes a base, a bearing housing, a bearing, a rotation shaft, a stator, a bushing, and a rotor. The bearing housing is installed on the base. The bearing is fixed inside the bearing housing. The rotation shaft is installed to be supported by and rotate on the bearing. The stator is disposed around the bearing housing. The bushing is coupled to the rotation shaft. The rotor is coupled to the bushing to rotate through interaction with the stator.