Bone Cement Mixing System With Gravity-Driven Monomer Transfer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing bone cement mixing systems face challenges in safely and reproducibly transferring monomer liquid into the powder component without air inclusion, conduit blockage, and uncontrolled mixing during storage, particularly in fully prepackaged systems.

Innovation Solution

A device utilizing a funnel-shaped outlet and inlet tube configuration for gravitational flow of monomer liquid into a cartridge containing PMMA bone cement powder, with features like a movable sphere to prevent powder bridges and a filter to prevent contamination, ensuring complete transfer without mechanical force.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If vacuum is applied to transfer monomer liquid into the cartridge, then complete transfer is achieved, but the system becomes more complex and requires additional vacuum generation components

Engineering Contradiction:
Improvemonomer liquid transfer completenessVSAvoidvacuum system complexity
Core Design Contradiction:
Quantity of substanceVSDevice complexity

Solution Approach 1:

The system uses the weight difference between the monomer liquid and air to create natural gravitational flow. The monomer liquid flows down the inclined funnel and into the cartridge automatically without requiring external vacuum or pressure systems. This self-service approach eliminates complex vacuum generation components while achieving complete liquid transfer.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The invention uses hydraulic principles by allowing the monomer liquid to flow under its own weight through a gravity-driven path. The inclined funnel geometry creates a continuous flow channel where liquid displacement occurs naturally, replacing the need for mechanical vacuum systems with a simpler gravity-based hydraulic flow mechanism.

Inventive Principle:
Principle #29Pneumatics and hydraulics

2Manufacturing precision

If manual mixing is used to combine powder and liquid, then complete mixing is achieved, but air bubbles are included in the bone cement paste

Engineering Contradiction:
Improvemixing completenessVSAvoidair bubble inclusion
Core Design Contradiction:
Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The invention replaces manual mechanical mixing with an automated gravity-driven flow system. The monomer liquid flows continuously down the inclined funnel and into the powder cartridge, creating a controlled mixing process that eliminates air bubble inclusion while maintaining mixing completeness through the natural flow dynamics of the system.

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

3Reliability

If the monomer liquid transfer conduit is made small to prevent powder penetration, then powder blockage is avoided, but transfer speed decreases

Engineering Contradiction:
Improveconduit blockage preventionVSAvoidmonomer liquid transfer speed
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The invention changes the geometry from a vertical narrow conduit to an inclined funnel structure. By utilizing the angular dimension of the funnel surface, the system achieves both adequate flow cross-sectional area for speed and sufficient inclination for gravity-driven flow. The funnel's sloped surfaces allow powder particles to be excluded while maintaining efficient liquid transfer through the inclined path.

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

4Stability of the object's composition

If fully prepackaged mixing systems are used, then uncontrolled mixing during storage is prevented, but safe and reproducible transfer of monomer liquid becomes difficult

Engineering Contradiction:
Improvecomponent separation stabilityVSAvoidmonomer liquid transfer ease
Core Design Contradiction:
Stability of the object's compositionVSEase of operation

Solution Approach 1:

The system is pre-assembled with the monomer liquid and powder cartridge in a stable, separated configuration. The inclined funnel is pre-positioned to receive the liquid, and the entire assembly is designed so that upon activation, the liquid automatically flows to the cartridge without requiring complex transfer operations. This preliminary arrangement maintains stability during storage while enabling easy, controlled transfer when needed.

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

Facilitates simple, reliable, and complete mixing of bone cement components by gravity, preventing air inclusion and conduit blockage, while maintaining sterility and ensuring consistent mixing ratios.

Implementation Method 1

the device is designed and configured to transfer a monomer liquid from the container into the cartridge by free gravitational flow via the funnel-shaped outlet and the inlet tube

Methodology Applied
Scientific EffectGravitational flow: Gravitation

Data Source

PatentEP4603176A1Bone cement mixing system with improved monomer fluid transfer
Publication Date: 2025.08.20 HERAEUS MEDICAL GMBH
  • EP4603176A1 patent drawingFigure 1
  • EP4603176A1 patent drawingFigure 2
  • EP4603176A1 patent drawingFigure 3

AI summary

The present invention relates to a device for mixing bone cement, comprising a cartridge 101 for holding a bone cement powder; a container 102 for holding a monomer liquid 118, wherein the container is fluidly connected to the cartridge 101; a cartridge head 104 arranged at a proximal end 103 of the cartridge, wherein the cartridge head has a passage 105; an inlet tube 106, wherein the inlet tube has a longitudinal axis 107; and a funnel-shaped outlet 108, wherein the funnel-shaped outlet has a funnel inner surface 109 which is at least partially arranged at an angle of no more than 60° to the longitudinal axis of the inlet tube; wherein the device is designed and configured to transfer a monomer liquid from the container into the cartridge by free gravitational flow via the funnel-shaped outlet and the inlet tube.