Automatic coffee machine equipped with a device for purging the coffee discharge duct

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Automatic coffee machines often leave residual brewed coffee in the dispensing system, which can affect the taste of subsequent brews, especially after extended periods of inactivity, and existing purging mechanisms can be complex and costly.

Innovation Solution

The implementation of a vent duct system connected to the solenoid valve, allowing the coffee evacuation conduit to be purged by gravity, synchronized with the stopping of the electric pump to ensure continuous flow without user disturbance, and utilizing a 3-way solenoid valve for both coffee and milk frothing systems to maintain a simple and economical design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a purging device is added to remove residual coffee from the evacuation conduit, then coffee quality is improved, but device complexity increases

Engineering Contradiction:
Improvecoffee qualityVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention extracts the purging function from a complex mechanical system and implements it through a simple gravity-based drainage mechanism with a solenoid valve-controlled air duct, removing residual coffee by creating a pressure differential that drives coffee out through the shortest path to the drain

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The purging system uses the machine's existing pump and solenoid valve to perform the purging operation automatically without requiring additional actuators or complex control mechanisms, making the system self-sufficient using already-available components

Inventive Principle:
Principle #25Self-service

2Reliability

If a purging mechanism is implemented to clear residual coffee, then coffee taste is improved, but manufacturing cost increases

Engineering Contradiction:
Improvecoffee tasteVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The solenoid valve serves dual functions: controlling coffee flow during normal operation and opening the air duct for purging operations, eliminating the need for a dedicated purging valve and reducing component count and manufacturing cost

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The invention uses a simple plastic drain tube and basic solenoid valve instead of expensive mechanical purging systems, opting for affordable components that achieve the purging function effectively without requiring precision engineering

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

3Device complexity

If the solenoid valve is used to open the air duct for purging, then device complexity is reduced, but the risk of coffee affecting the solenoid valve increases

Engineering Contradiction:
Improvedevice complexityVSAvoidcoffee contamination risk
Core Design Contradiction:
Device complexityVSObject-affected harmful factors

Solution Approach 1:

The air duct acts as an intermediary pathway that allows purging coffee to be directed away from the solenoid valve, creating a separate drainage route that protects the valve from coffee contamination while still enabling effective purging

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

Instead of trying to protect the solenoid valve from coffee by complex sealing mechanisms, the invention inverts the approach by creating a dedicated air duct that actively directs purging coffee away from the valve, using the valve's opening action to initiate a protective drainage flow

Inventive Principle:
Principle #13The other way round (Inversion)

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 effectively removes residual coffee without affecting the solenoid valve's function, ensuring consistent coffee quality and simplifying the machine's design while maintaining economic viability.

Implementation Method 1

l'orifice d'admission d'air est adapté pour créer une différence de pression capable de propulser le café résiduel vers le drain

Methodology Applied
Scientific EffectPressure differential: Pressure Gradient

Implementation Method 2

Le conduit d'évacuation du café est orienté en pente descendante pour faciliter l'écoulement du café sous l'effet de la gravité

Methodology Applied
Scientific EffectGravity: Gravitation

Data Source

PatentEP3878320B1Automatic coffee machine equipped with a device for purging the coffee discharge duct
Publication Date: 2022.08.10 SEB SA
  • EP3878320B1 patent drawingFigure 1~2
  • EP3878320B1 patent drawingFigure 3~4

AI summary

The invention relates to an automatic coffee machine (1) comprising a control circuit (60), a dispensing head (50) including at least one coffee outlet (51) and a brewing device (10), said brewing device (10) comprising a brewing chamber (12) having a top opening (16) for receiving ground coffee and a press piston (14) movable between a high retraction position in which it is located above the brewing chamber (12) and a low tamping position in which it enters the brewing chamber (12) through the top opening (16), said brewing chamber (12) being supplied with hot water by an electric pump (9) and being fluidly connected to at least one coffee outlet (51) by a coffee discharge conduit (30) passing through the press piston (14).According to the invention, a venting duct (40) is connected to the discharge duct (30) at a junction zone (49) arranged near the press piston (14) and the venting duct (40) includes a solenoid valve (47), the control circuit (60) controlling the solenoid valve (47) to move it from a closed position of the venting duct (40) to an open position of the venting duct (40), just after stopping the electric pump (9) at the end of the brewing of a coffee, so that the coffee, present in the discharge duct (30) after stopping the electric pump (9), flows by gravity, continuously following the coffee already dispensed.