Hot Beverage Boiler Control Using Downstream Thermostat Sensing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing coffee makers with sophisticated control systems for maintaining water temperature at 90°C to 96°C are costly due to the use of expensive components, and simple mechanical thermostats can lead to inconsistent behavior and thermal mixing issues.

Innovation Solution

A device with a boiler, a heating means, and a combination of a switching device and a detecting device that monitors the temperature downstream of the boiler, using a three-way valve to control the heating process based on the temperature influenced by liquid displacement, ensuring accurate termination of heating before the pump starts, thus avoiding thermal mixing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a sophisticated control system with electronic control device, temperature sensor, and water delivery counter is used, then temperature control precision is improved, but device cost increases

Engineering Contradiction:
Improvetemperature control precisionVSAvoiddevice cost
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces expensive electronic control devices, temperature sensors, and water delivery counters with a simple mechanical thermostat that can be easily replaced. The mechanical thermostat is a low-cost component that performs the essential temperature control function without requiring complex electronics or additional sensors.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent extracts the temperature control function from the complex electronic control system and isolates it to a dedicated mechanical thermostat component. This allows the thermostat to be positioned downstream of the boiler where it can directly sense water temperature and control the heating element without interference from other system components.

Inventive Principle:
Principle #2Taking out (Extraction)

2Device complexity

If a mechanical thermostat is used for temperature control, then device cost is reduced, but temperature control consistency deteriorates due to thermal mixing

Engineering Contradiction:
Improvedevice costVSAvoidtemperature control consistency
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent introduces a three-way valve as an intermediary component between the boiler and the thermostat. This valve creates a separate sensing pathway that allows the thermostat to monitor water temperature at a specific point in the dispensing process, preventing thermal mixing from affecting the temperature measurement and control accuracy.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent positions the thermostat downstream of the boiler to detect temperature changes before the water reaches the dispensing point. This preliminary detection allows the system to adjust heating in advance, ensuring consistent temperature control without the need for complex feedback systems.

Inventive Principle:
Principle #10Preliminary action

3Speed

If temperature is monitored inside the boiler, then heating control responsiveness is improved, but thermal mixing between hot and cold water occurs

Engineering Contradiction:
Improveheating control responsivenessVSAvoidthermal mixing
Core Design Contradiction:
SpeedVSObject-generated harmful factors

Solution Approach 1:

The patent moves the temperature monitoring point from the vertical dimension inside the boiler to a horizontal dimension downstream in the water pathway. By positioning the thermostat in the water flow path after the boiler, the system monitors temperature at a different spatial location where thermal mixing has already occurred naturally, allowing accurate sensing without causing additional mixing.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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

This solution allows for reliable temperature control without the need for expensive components, ensuring consistent brewing by deactivating the heating means when the liquid reaches a predetermined temperature influenced by displacement, thus maintaining the desired brewing temperature range.

Implementation Method 1

a heating means for supplying heat to the liquid

Methodology Applied
Scientific EffectJoule heating: Joule Heating

Implementation Method 2

a detecting device which is capable of monitoring the temperature of liquid that is present inside the transporting system

Methodology Applied
Scientific EffectTemperature detection: Temperature Gradient

Implementation Method 3

a three-way valve arranged at an outlet of the boiler

Methodology Applied
Scientific EffectFluid flow control: Valve

Data Source

PatentEP2040591B1Method for controlling the operation of a device for dispensing hot liquid
Publication Date: 2011.12.14 KONINKLIJKE PHILIPS NV
  • EP2040591B1 patent drawingFigure 1
  • EP2040591B1 patent drawingFigure 2
  • EP2040591B1 patent drawingFigure 3

AI summary

A beverage maker (1) for making a hot beverage comprises a boiler (30) for heating a quantity of water, and a pump (40). When the beverage maker (1) is operated, a heating element (32) of the boiler (30) is activated, and the water inside the boiler (30) is heated. When the temperature of the water has reached a predetermined value, a thermostat (63) which is arranged in an electronics circuit (41) for energizing the pump (40) is closed, and a pumping action is started. As a result, water exits the boiler (30), and passes a thermostat (62) which is arranged downstream of the boiler (30), and which is arranged in an electronics circuit (34) for energizing the heating element (32). Under the influence of the hot water, a set point of this thermostat (62) is reached, and this thermostat (62) opens, so that the electronics circuit (34) for energizing the heating element (32) is interrupted, and the heating element (32) is deactivated.