Coffee grinding and proportioning device, especially for espresso machines

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Solution Overview

Problem

Existing coffee grinders lack the accuracy and homogeneity needed for espresso machines, as they either rely on inaccurate weight measurement methods or modify the grinding speed to achieve precision, affecting the final infusion quality.

Innovation Solution

A coffee grinder with a proportioner assembly using an Archimedean screw for precise powder evacuation and homogenization, combined with a programmable controller and modular configuration to ensure exact quantity and homogeneity, while preventing lump formation through adjustable disc devices and conical conveyors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If weight measurement is used to control coffee quantity, then quantity precision is improved, but measurement accuracy deteriorates due to variable grinding conditions

Engineering Contradiction:
Improvecoffee powder quantityVSAvoidweight measurement accuracy
Core Design Contradiction:
Quantity of substanceVSMeasurement precision

Solution Approach 1:

The patent replaces the mechanical weighing system with an optical measurement system. A photodetector measures the light intensity reflected from or transmitted through the coffee powder in the portafilter. Since the relationship between light intensity and coffee quantity is more stable and less affected by grinding variables than weight measurement, this substitution improves measurement precision while maintaining quantity control accuracy.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If grinding speed is reduced to improve weighing accuracy, then measurement precision is improved, but productivity deteriorates

Engineering Contradiction:
Improveweighing accuracyVSAvoidgrinding speed
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The patent eliminates the need to slow down grinding by replacing weight-based measurement with optical measurement. The optical sensor can accurately measure coffee quantity regardless of grinding speed, allowing the grinder to maintain high productivity while achieving precise quantity control through light intensity measurement rather than weight measurement.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Ease of operation

If coffee powder is held waiting for infusion preparation, then convenience is improved, but quality deteriorates due to hygroscopic properties

Engineering Contradiction:
Improvepreparation convenienceVSAvoidcoffee quality
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent divides the coffee delivery system into segmented portions, with the ability to prepare and dispense individual serving sizes on demand. The proportional dispenser allows coffee to be ground and delivered in precise, small quantities rather than preparing large amounts in advance, reducing the need to hold coffee powder waiting and minimizing quality degradation from hygroscopic absorption.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system performs preliminary grinding and immediate dispensing of the exact required quantity before the infusion preparation begins. By grinding and delivering coffee on-demand in precise proportions rather than pre-preparing bulk amounts, the coffee is held for minimal time, preserving quality while maintaining operational convenience through automated control.

Inventive Principle:
Principle #10Preliminary action

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 highly accurate and homogeneous coffee powder dispensing, maintaining optimal grinding speed and preventing lumps, ensuring consistent flavor and quantity for espresso preparation.

Implementation Method 1

a proportioner assembly (5) with a distributor compartment (5) closed on the upper part by a motor-holder head (81) supporting a motor (8) used to drive an Archimedean screw (7)

Methodology Applied
Scientific EffectArchimedean screw: Archimedes Screw

Implementation Method 2

The distributor compartment (5) is functionally associated with a loading cell (6) capable of exactly measuring any changes in weight

Methodology Applied
Scientific EffectWeight measurement: Balance

Implementation Method 3

a conical conveyor (51) whose inner surface is swept out by a doctor (52) coaxial to and integral with the Archimedean screw (7)

Methodology Applied
Scientific EffectMechanical sweeping: Brush

Data Source

PatentEP3214984B1Coffee grinding and proportioning device, especially for espresso machines
Publication Date: 2019.07.03 CGTECNICA SRL
  • EP3214984B1 patent drawingFigure 1
  • EP3214984B1 patent drawingFigure 2
  • EP3214984B1 patent drawingFigure 3

AI summary

A simple or multiple coffee grinder equipment, supplemented by a proportioner device, the latter equipped with means for measuring the weight of the ground product. The proportioner device controls the operation of the individual coffee grinders, and stops grinding upon reaching the desired weight of ground product for each individual quality. The proportioner device also includes a special mechanism to improve the mixing and homogenization of the ground product, as well as to prevent the formation of lumps.