Plunger-Based Door Actuation Detection for Handle-Free Appliances
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing household appliances, particularly refrigeration appliances, often lack reliable methods to detect user actuation on door handles, leading to ergonomic issues and unreliable operation, especially for visually impaired users or those in low-light conditions, due to limited sensor regions and interference from door torsion.
Innovation Solution
A method and apparatus using a plunger influenced by a drive unit with a bracing force less than the door-opening force, detecting arbitrary strokes with a sensor, and comparing sensor signals to determine user actuation, independent of stroke direction, and a door opening apparatus with a mechanical bracing unit and circuit for detecting induced voltage without electrical energy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If a sensor unit is used to detect user actuation on the door, then the door opening can be automated, but the sensor region is limited and unreliable, especially for visually impaired users or in low-light conditions
Solution Approach 1:
The patent combines the sensor unit with the door opening mechanism into an integrated apparatus. The sensor unit is positioned to detect strokes on the door, and when actuation is detected, the door opening mechanism automatically opens the door. This merging eliminates the need for separate sensors and mechanical components, providing both automated operation and ergonomic usability through a unified system.
Solution Approach 2:
The patent introduces a plunger as an intermediary element between the door and the sensor unit. The plunger is movable relative to the door and transmits the stroke force from the user to the sensor unit, which detects the actuation. This intermediary mechanism expands the effective sensor region across the door surface, allowing users to actuate the door from various positions without needing to locate a specific small sensor area.
2Area of stationary object
If a plunger is used to detect door actuation, then the sensor region is expanded, but the device complexity increases
Solution Approach 1:
The patent merges the plunger, sensor unit, and door opening mechanism into a single integrated apparatus. The plunger is positioned within the door opening mechanism structure, and the sensor unit is integrated with the same mechanism. This consolidation expands the sensor region while minimizing the increase in overall device complexity by sharing structural components.
Solution Approach 2:
The door opening mechanism serves multiple functions: it acts as the actuating mechanism for opening the door, houses the sensor unit, and provides the structural framework for the plunger. This multi-functionality reduces the need for separate components, thereby expanding the sensor region without proportionally increasing device complexity.
3Reliability
If separate sensors are used to detect door actuation, then the detection reliability is improved, but the energy consumption increases
Solution Approach 1:
The patent combines the sensor unit with the door opening mechanism, allowing the same apparatus to both detect actuation and execute the door opening action. This integration eliminates the need for separate sensor systems and control mechanisms, maintaining reliable actuation detection while reducing overall energy consumption by sharing power requirements across functions.
Solution Approach 2:
The door opening mechanism itself serves as the actuating force source, eliminating the need for additional motors or actuators that would consume extra energy. The mechanism uses the door's own weight and the user's stroke force, combined with mechanical advantage, to open the door automatically upon detection, thereby reducing energy consumption while maintaining detection reliability.
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
Enhances reliable detection of user actuation on doors without handles, improving ergonomic usability and reducing energy consumption by expanding the sensor region and eliminating the need for separate sensors.
Implementation Method 1
A plunger (20) in a closed state of the door is movably arranged on the body (10) in a direction of a longitudinal axis of the plunger... the plunger is moved by means of a drive unit (22) until a plunger head (24) of the plunger braces against the door inner side (14)
Implementation Method 2
An arbitrary stroke of the plunger is detected by means of a sensor unit (26) and a sensor signal is allocated to the detected stroke
Implementation Method 3
a door opening mechanism of the household appliance is activated and owing to an opening signal the door opens at least by an angle that can be predetermined
Data Source
AI summary
A method determines an actuation of a door of a household appliance by a user. The door closes an access opening of a body of the appliance to an interior space by virtue of an elastic seal that is arranged on the door inner side and braces circumferentially against a region of an edge of the access opening. A plunger is moved by a drive unit until a plunger head braces against the door inner side. The plunger is influenced into an opening direction of the door by the drive unit using a bracing force that is smaller than a force for opening the door. An arbitrary stroke of the plunger is detected by a sensor and a sensor signal is allocated to the detected stroke. The sensor signal is compared with a comparison value and the actuation by the user is determined in dependence upon the comparison.