Bi-Stable Elevator Brake Actuator for Wide Guide Rail Gaps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Elevator safety brakes with magnetic actuators face inefficiencies due to varying gaps between actuators and guide rails, leading to noise and wear, as existing designs struggle to maintain effective braking across different gap sizes.
Innovation Solution
A bi-stable electromagnetic brake actuator with a movable core and permanent magnet assembly that allows orthogonal movement, enabling magnetic attraction and efficient braking across a range of gap sizes from 0.5 mm to 3.6 mm, using a coil and circuitry to control the movement and magnetic fields for effective engagement and disengagement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of stationary object
If sliding guides are used to reduce excessive gaps between actuators and rails, then the gap is reduced, but noise and wear are introduced
Solution Approach 1:
The patent replaces the mechanical sliding guide system with a magnetic field-based actuation system. The magnetic actuator uses electromagnetic fields to control the brake shoes, eliminating the need for physical sliding contacts and thereby reducing mechanical wear and noise while maintaining effective braking across varying gaps.
Solution Approach 2:
The patent employs a bi-stable magnetic actuator that can maintain stable magnetic fields at two different positions, allowing the system to adapt to varying gap conditions without requiring precise mechanical guidance. This parameter-based control enables effective braking across a range of gap sizes without introducing mechanical wear or noise.
2Reliability
If magnetic actuators are used in safety brakes, then braking efficiency is improved, but the gap between actuators and rails must be well defined
Solution Approach 1:
The patent uses a bi-stable magnetic actuator that can dynamically adjust and maintain stable magnetic fields at two different positions, allowing the system to adapt to varying gap conditions. This dynamic capability enables reliable braking efficiency without requiring precisely defined gap dimensions, as the magnetic field can compensate for manufacturing tolerances.
3Adaptability or versatility
If the gap between actuators and guide rails varies, then adaptability is improved, but braking efficiency deteriorates
Solution Approach 1:
The patent employs a bi-stable magnetic actuator that can maintain stable magnetic fields at two different positions, allowing the system to adapt to varying gap conditions. By changing the magnetic field parameters rather than relying on fixed mechanical positioning, the system maintains effective braking across a range of gap sizes from 0.5 mm to 3.6 mm.
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 bi-stable electromagnetic brake actuator improves braking performance by accommodating varying gaps, reducing noise and wear, and maintaining effective braking across large gaps, while ensuring controlled movement and efficient magnetic interaction.
Implementation Method 1
a coil disposed in the fixed core and configured to generate magnetic fields of opposite polarities when supplied with opposing currents, respectively
Implementation Method 2
enabling magnetic attraction and efficient braking across a range of gap sizes
Data Source
Figure 1
Figure 2A~2F
Figure 3
AI summary
A bi-stable brake actuator is provided and includes a fixed core movable in a first direction, a coil disposed in the fixed core and configured to generate magnetic fields of opposite polarities when supplied with opposing currents, respectively, a movable core disposed to move between retracted and extended positions with respect to the fixed core and the coil in exclusively a second direction defined orthogonally with respect to the first direction and a permanent magnet assembly. The permanent magnet assembly is disposed to move between first and second positions in accordance with the coil being supplied with the opposing currents, respectively.