Laundry Dryer Steam Recirculation for Gentle Crease Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current steam generators in rotary-drum laundry dryers are expensive, require demineralized water, and can be dangerous due to high-pressure steam jets, which pose risks to fabrics and increase manufacturing costs.
Innovation Solution
A home laundry drier with an integrated steam generator that uses ambient-pressure steam produced from demineralized water, where the steam is generated within the hot-air generator and fed into the drying tub via a recirculating conduit, utilizing the airflow to distribute it safely and efficiently, and a process water recovery circuit to reuse condensed moisture.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If high-pressure steam is used to cover all laundry, then steam distribution effectiveness is improved, but fabric safety deteriorates due to potential damage to laundry items closest to the nozzle
Solution Approach 1:
The patent changes the pressure parameter of steam from high-pressure to ambient-pressure, fundamentally altering the delivery mechanism. Instead of forcing steam through pressure, the system uses a spray nozzle to atomize water into fine droplets that evaporate and form steam throughout the drum, eliminating the harmful high-pressure jet while maintaining effective steam distribution across all laundry items
Solution Approach 2:
The patent replaces the mechanical high-pressure steam generation system with a thermal evaporation system. Rather than using a pressurized boiler and high-pressure steam jet, the system uses a spray nozzle to deliver water droplets that are then evaporated by the heated air in the drum, substituting a mechanical pressure-based system with a thermal field-based system that is gentler on fabrics
2Power
If a separate boiler is used for steam generation, then steam production capability is improved, but device complexity and manufacturing cost worsen
Solution Approach 1:
The patent merges the steam generation function with the existing hot air generator system. The spray nozzle delivers water into the drum where it is evaporated by the heated air already present in the drying cycle, eliminating the need for a separate boiler and integrating steam production into the existing thermal processing system
Solution Approach 2:
The patent makes the hot air generator system multi-functional by enabling it to serve both as a drying heat source and as a steam generator. The same heated air that dries the laundry also evaporates the sprayed water to produce steam for fabric refreshment, allowing one system to perform multiple functions and reducing overall device complexity
3Reliability
If demineralized water is used in the boiler, then steam generator reliability is improved by preventing lime scale formation, but operational cost and water consumption worsen
Solution Approach 1:
The patent implements a self-service system where the steam generation process uses ordinary tap water sprayed into the drum, and the condensed moisture from the steam is automatically collected and recycled back into the system. The system serves itself by capturing and reusing its own water resources, eliminating the need for demineralized water while maintaining reliability through the closed-loop water management
Solution Approach 2:
The patent recovers the water that would otherwise be discarded as waste. The condensed moisture from steam condensation on the drum walls and laundry is collected and fed back into the spray nozzle for re-evaporation, creating a closed-loop system that continuously recycles water and eliminates the need for continuous fresh water input or demineralization
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 solution provides a gentler and cost-effective steam distribution method that reduces fabric creasing without the risks of high-pressure steam, utilizing ambient-pressure steam and recycled water to enhance drying efficiency and safety.
Implementation Method 1
an integrated steam generator that uses ambient-pressure steam produced from demineralized water
Implementation Method 2
the steam is generated within the hot-air generator and fed into the drying tub via a recirculating conduit, utilizing the airflow to distribute it safely and efficiently
Implementation Method 3
The air/air heat exchanger provides for rapidly cooling the airflow from the drying tub to condense the surplus moisture in the airflow
Implementation Method 4
the heater provides for rapidly heating the airflow from the heat exchanger back to the drying tub, so that the air flowing into the drying tub is heated rapidly to a temperature higher than or equal to that of the same air flowing out of the drying tub
Data Source
AI summary
A home laundry drier (1) having a drying tub (3) for housing the laundry to be dried, and a closed-circuit, hot-air generator (4) for circulating a stream of hot air into the drying tub (3). The hot-air generator (4) has a tank (16) containing a predetermined amount of water; an auxiliary heater (17) for converting the water in the tank (16) to steam; and a steam exhaust manifold (18) which communicates with the air recirculating conduit (7), between the condenser (9) and the main heater (10) of the hot-air generator (4), to feed the steam produced in the tank (16) into the drying tub (3) via the end portion of the air recirculating conduit (7).