Pressure-Responsive Hair-Cutting Unit to Prevent Skin Irritation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hair-cutting appliances, particularly rotary shavers, cause skin irritation due to excessive pressure leading to skin cutting through hair-entry openings during shaving.
Innovation Solution
A hair-cutting unit with a safety mechanism that allows for stepped variation between discrete stages of the cutting track surface relative to the skin-supporting surface, activating a retracted stage when excessive pressure is detected, using sensors and actuators to instantaneously adjust the external cutting member's position.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the external cutting member is pressed with excessive force on the skin, then hair-cutting performance is improved, but skin cutting occurs causing irritation
Solution Approach 1:
The external cutting member is made dynamically adjustable in its position relative to the skin-supporting structure. A safety mechanism enables stepped variation between discrete stages of the level of the cutting track surface, allowing the system to transition from a static to a dynamic configuration that adapts to operating conditions.
Solution Approach 2:
A sensor detects the pressure exerted by the external cutting member on the skin and provides feedback to the control unit. The control unit processes this pressure information and activates the actuator to adjust the cutting member's position, creating a closed-loop feedback system that prevents skin cutting while maintaining optimal hair-cutting performance.
2Manufacturing precision
If the cutting track surface protrudes to maximum extent for optimal hair-cutting, then hair-cutting closeness is improved, but skin cutting risk increases under excessive pressure
Solution Approach 1:
The system dynamically adjusts the protrusion distance of the cutting track surface relative to the skin-supporting structure based on detected pressure conditions. The external cutting member can be positioned at a first distance for optimal hair-cutting performance or at a second distance (retracted) when excessive pressure is detected, eliminating the need to permanently compromise between performance and safety.
Solution Approach 2:
The system changes the positional parameter of the external cutting member based on pressure conditions. When pressure exceeds a threshold, the cutting member is retracted to a safer position, effectively changing the geometric parameter to prevent skin cutting while maintaining the ability to return to the optimal position when conditions are normal.
3Object-affected harmful factors
If a safety mechanism is added to prevent skin cutting, then skin comfort is improved, but device complexity increases
Solution Approach 1:
The patent replaces complex mechanical pressure-regulation mechanisms with a sensor-based detection system and an actuator-controlled positioning system. This substitution of mechanical systems with sensor-actuator systems provides more precise and reliable safety control while potentially reducing mechanical complexity through electronic control.
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
Prevents skin cutting and minimizes irritation by adjusting the cutting member's position in response to pressure, maintaining optimal hair-cutting performance without compromising skin comfort.
Implementation Method 1
A sensor is integrated in the skin-supporting structure and is configured to detect the pressure exerted by the external cutting member on the skin
Implementation Method 2
An actuator is integrated in the skin-supporting structure and is configured to displace the external cutting member relative to the skin-supporting structure
Data Source
AI summary
A hair-cutting unit (4) for use in a hair-cutting appliance comprises an external cutting member (5) having hair-entry openings in a cutting track surface (58), an internal cutting member (6) having at least one hair-cutting element and being movable with respect to the external cutting member (5), and a skin-supporting structure (7) having a skin-supporting surface (71) for contacting a portion of skin to be subjected to a hair-cutting action. The external cutting member (5) is displaceable relative to the skin-supporting structure (7), and the hair-cutting unit (4) further comprises a safety mechanism which is designed to enable stepped and instantaneous variation between at least two discrete stages of a level (lc) of the cutting track surface (58) with respect to a level (ls) of the skin-supporting surface (71), in relation to pressure exerted by the external cutting member (5) on the skin.