Brewing Piston Deflection for Volume-Independent Pomace Ejection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing brewing groups in automatic coffee machines face challenges in ensuring complete ejection of pomace regardless of its volume, leading to potential jamming or incomplete ejection due to rigid kinematic coupling between the brewing piston and the brewing chamber.

Innovation Solution

The introduction of deflection means on the connecting link allows the control lever to deflect based on pomace volume, decoupling the brewing piston's movement from the brewing chamber's, ensuring uniform compression and complete ejection through staggered contact edges or detents, and optionally using an elastic element for additional compensation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a rigid kinematic coupling is used between the brewing piston and brewing chamber, then the structure is simple and reliable, but the pomace ejection is incomplete or causes jamming when pomace volume varies

Engineering Contradiction:
Improvepomace ejection completenessVSAvoidkinematic coupling structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies the dynamics principle by making the control lever deflectable rather than rigidly coupled. The control lever can rotate about an axis and deflect relative to the brewing chamber, allowing the brewing piston to achieve different positions based on pomace volume. This dynamic adjustment ensures complete ejection while maintaining structural simplicity.

Inventive Principle:
Principle #15Dynamics

2Reliability

If a safety distance is maintained between the brewing piston and brewing chamber upper part, then jamming is avoided, but the compression force is insufficient and pomace ejection is incomplete

Engineering Contradiction:
Improvepomace ejection completenessVSAvoidpomace jamming
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The deflection mechanism allows the brewing piston to dynamically adjust its position relative to the brewing chamber upper part. When pomace volume is small, the control lever deflects to allow the piston to reach closer to the upper part, eliminating the safety distance and ensuring complete ejection. When pomace volume is large, the piston naturally maintains an appropriate distance, avoiding jamming.

Inventive Principle:
Principle #15Dynamics

3Device complexity

If the brewing piston is directly driven by the control lever, then the structure is simple, but the compression force varies with pomace volume leading to inconsistent compression quality

Engineering Contradiction:
Improvedrive mechanismVSAvoidcompression uniformity
Core Design Contradiction:
Device complexityVSManufacturing precision

Solution Approach 1:

The patent applies parameter changes by modifying the control lever's rotational position and deflection angle based on pomace volume. The spring element provides a restoring force that adjusts the control lever's position, thereby changing the compression parameters to maintain uniform compression quality regardless of pomace volume variations.

Inventive Principle:
Principle #35Parameter changes

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 and complete ejection of pomace of varying volumes without jamming, ensuring efficient operation and maintenance by eliminating the need for a safety distance between the brewing piston and the brewing chamber's upper part.

Implementation Method 1

the spring device has a largely linear and flat spring characteristic in the compression load range

Methodology Applied
Scientific EffectSpring: Spring

Implementation Method 2

deflection means on the connecting link, which enable deflection of the control lever depending on the pomace volume

Methodology Applied
Scientific EffectMechanical deflection:

Implementation Method 3

an elastic element (42) arranged between the drive of the control lever (6) and the brewing piston (4)

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP2567644B1Device for volume-independent marc pressing
Publication Date: 2015.08.05 BSH HAUSGERATE GMBH
  • EP2567644B1 patent drawingFigure 1
  • EP2567644B1 patent drawingFigure 2
  • EP2567644B1 patent drawingFigure 3

AI summary

A brewing unit of a fully automatic coffee machine for household purposes with two parallel side walls (2), with a brewing chamber arranged between them with a brewing cylinder, with a brewing piston (4) slidably mounted therein, with a control lever (6) rotatably mounted on the brewing chamber for driving the brewing piston (4), with a cam (8) on the side walls (2) and with deflection means (10) on the cam (8) for deflecting the control lever (6) is further developed by a deflection of the control lever (6) that is dependent on the coffee grounds volume.