Home Appliance Viewing Window with Vibration-Based Knock Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional home appliances face challenges in accurately detecting knock inputs due to vibration misinterpretation from various sources, especially in high-temperature environments, and require additional space for advanced sensors, leading to inefficient detection and installation limitations.
Innovation Solution
A home appliance with a 3-axis vibration sensor module installed on the rear surface of the front plate, connected via a hinge bracket, detects vibrations through solid media, considering directionality and temperature resistance, allowing precise knock detection and minimizing attenuation, integrated with a lamp control system for visibility through a viewing window.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a sound wave sensor is attached to the door to detect knock inputs, then knock detection is enabled, but the sensor malfunctions due to high-temperature heat transmission to the door
Solution Approach 1:
The patent introduces a hinge bracket as an intermediary component that transmits vibrations from the door to the sensor. The sensor is installed on the rear surface of the front plate rather than directly on the door, using the hinge bracket as a mediating structure to convey knock vibrations while isolating the sensor from direct heat exposure in the high-temperature environment
Solution Approach 2:
The patent replaces sound wave detection (acoustic method) with vibration detection (mechanical method). Instead of using a sound wave sensor that requires a single medium for sound transmission, the system uses a vibration sensor that detects mechanical vibrations transmitted through solid media (door → hinge bracket → sensor), which is more reliable in high-temperature environments
2Ease of operation
If a sound wave sensor is used to detect knock inputs, then knock detection is possible, but various vibrations from other sources are erroneously detected as knock inputs
Solution Approach 1:
The patent applies local quality by analyzing vibrations in specific directional components. The vibration sensor detects vibrations along multiple axes, and the control unit identifies knock inputs by examining the directional characteristics and temporal patterns of vibrations, distinguishing true knocks from other vibrations based on their localized directional properties
Solution Approach 2:
The system uses dynamic analysis of vibration patterns over time. The control unit monitors the temporal characteristics, frequency, and directional changes of vibrations, enabling dynamic discrimination between knock inputs (which have specific dynamic patterns) and other vibrations (which have different dynamic signatures)
3Reliability
If the sensor is installed away from the door to avoid heat, then heat interference is reduced, but the detection accuracy decreases due to vibration attenuation
Solution Approach 1:
The hinge bracket serves as an effective intermediary that maintains strong mechanical coupling between the door and sensor while providing thermal isolation. This mediating structure transmits vibrations with minimal attenuation despite the increased distance, because it provides a direct solid mechanical path for vibration transmission
Solution Approach 2:
The patent utilizes the rigid structural geometry of the hinge bracket and front plate assembly to efficiently transmit vibrations. The solid media connection through these structural components ensures that vibration energy is transmitted effectively over the distance from the door to the sensor location on the rear surface
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
Accurate detection of knock inputs is achieved, enabling doorless visibility into the appliance's interior, improving usability and reducing power consumption, while allowing sensor installation flexibility and reducing heat interference.
Implementation Method 1
a vibration sensor, which detects vibrations transmitted through solid media, is installed on the rear surface of the front plate
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Proposed is a home appliance in which a reception space defined in the home appliance can be seen from the outside through a viewing window without opening a door. In the home appliance, the viewing window is mounted to the door, and when a user knocks on the door, a knock input by the user is detected and the inside of the reception space is illuminated such that the inside of the reception space can be seen from the outside through the viewing window. Accordingly, a user can see the inside of the reception space by a simple motion without opening the door.