Vibration Actuator Gap Damping for Wide-Band Haptic Output
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vibration actuators face challenges in generating a suitable vibration output across a wide frequency band while being reduced in size, which is essential for modern electronic devices to provide effective feedback and realism to users.
Innovation Solution
A vibration actuator design featuring a movable magnet with a pillar shape and a coil assembly, where the movable body is supported by elastic support parts and housed within a cylindrical case, generating a pipe resistance through fluid flow in a gap between the inner and outer surfaces, allowing for vibration in a wide frequency band without increasing size or weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the vibration actuator is reduced in size to fit modern electronic devices, then the device compactness is improved, but the vibration output and frequency band coverage deteriorate
Solution Approach 1:
The patent introduces a fluid (air) into the gap between the movable body and fixed body, using fluid dynamics to generate pipe resistance that enhances vibration output. The fluid flow creates drag force on the movable body, amplifying the vibration effect without requiring larger actuator dimensions, thus resolving the contradiction between compact size and vibration output capability
Solution Approach 2:
The patent changes the physical state and flow parameters of the fluid in the gap to optimize vibration performance. By controlling fluid flow rate, viscosity, and pressure, the system achieves enhanced vibration output in a compact configuration, addressing the limitation of small size while maintaining high vibration capability
2Volume of moving object
If the coil and magnet are positioned closer to reduce size, then the actuator compactness is improved, but the risk of coil damage from impact increases
Solution Approach 1:
The patent introduces fluid as an intermediary substance in the gap between the movable body (containing magnet) and fixed body (containing coil). This fluid layer acts as a cushion that absorbs impact energy, preventing direct contact between the magnet and coil during impact events, thus protecting the coil from damage while maintaining compact dimensions
Solution Approach 2:
The fluid in the gap provides beforehand cushioning by being pre-positioned between the movable and fixed bodies. When impact occurs, the fluid compresses and dissipates energy before the magnet can collide with the coil, providing proactive protection against damage while allowing compact component arrangement
3Volume of moving object
If the gap between movable body and fixed body is reduced to minimize size, then the actuator compactness is improved, but the vibration frequency band coverage deteriorates
Solution Approach 1:
The fluid in the gap provides variable resistance that can adapt to different vibration frequencies. The fluid's compressibility and flow characteristics allow the system to respond to a wide range of frequencies, enabling compact actuators to achieve broad frequency band coverage by utilizing fluid dynamic properties rather than relying solely on mechanical gap dimensions
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
This configuration enables the generation of a suitable vibration output across a wide frequency band, enhancing user feedback and realism in electronic devices while maintaining a compact size, without damaging the coil and ensuring durability.
Implementation Method 1
a coil and a main body part... the movable body is vibratable in an axial direction of the movable body
Implementation Method 2
configured to cause a flow of a fluid in a direction opposite to a direction of movement of the movable body in the gap and to generate a pipe resistance to the fluid
Implementation Method 3
supports the movable body via an elastic support part such that the movable body is vibratable
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is a vibration actuator including: a movable body (20) including a magnet (21) having a pillar shape; and a fixing body (40) including a coil (60) and a main body part (42). The main body part (42) includes an inner peripheral surface (42a), which surrounds the movable body (20) with a gap (G) between the inner peripheral surface (42a) and an outer peripheral surface (20a) of the movable body (20) inside the coil (60), and supports the movable body (20) via an elastic support part (81, 82) such that the movable body (20) is vibratable in an axial direction of the movable body (20). The vibration actuator is configured to cause a flow of a fluid in a direction opposite to a direction of movement of the movable body (20) in the gap (G) and to generate a pipe resistance to the fluid.