Infusion Pump Rotor Rotation Direction Detection

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Solution Overview

Problem

Existing infusion pumps cannot detect the reverse rotation of the drive motor's rotor, which is necessary for mitigating occlusions during drug delivery, limiting their ability to safely and accurately administer medication.

Innovation Solution

An infusion pump equipped with a rotational direction detection device that generates detection information for both forward and reverse rotations of the drive motor's rotor, allowing the control unit to differentiate between the two and adjust the motor's operation accordingly, including reversing it when occlusions are detected.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a rotational direction detection device is added to detect both forward and reverse rotations, then the reliability of drug delivery is improved, but the device complexity increases

Engineering Contradiction:
Improvereliability of drug deliveryVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The rotational direction detection device is designed to perform multiple functions: detecting forward rotation, detecting reverse rotation, and providing rotational speed information. This multi-functional approach improves reliability without requiring separate detection systems for each function, thereby limiting the increase in device complexity.

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

2Productivity

If the rotor is reversely rotated to mitigate occlusion, then the productivity of drug delivery is improved, but the measurement precision of rotational direction is worsened

Engineering Contradiction:
Improveproductivity of drug deliveryVSAvoidmeasurement precision of rotational direction
Core Design Contradiction:
ProductivityVSMeasurement precision

Solution Approach 1:

The control unit receives detection information from the rotational direction detection device and uses this feedback to determine whether the rotor is rotating forward or in reverse. This feedback mechanism enables precise measurement of rotational direction even during reverse rotation for occlusion mitigation, while maintaining the ability to quickly restore productivity.

Inventive Principle:
Principle #23Feedback

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

Enables safe and accurate drug delivery by detecting and responding to occlusions with reverse rotation, ensuring continuous and reliable infusion.

Implementation Method 1

an optical coupler which obtains a first output waveform signal and a second output waveform signal different from the first output waveform signal by irradiating the encoder plate with light

Methodology Applied
Scientific EffectOptical detection: Photoelectric Effect

Data Source

PatentEP3323447B1Infusion pump
Publication Date: 2021.06.09 TERUMO KK
  • EP3323447B1 patent drawingFigure 1
  • EP3323447B1 patent drawingFigure 2
  • EP3323447B1 patent drawingFigure 3

AI summary

[Problem] Provided is an infusion pump in which a forward rotation and a reverse rotation of a rotor of a drive motor can be detected so as to be able to safely deliver drug to a patient. [Means for Resolution] An infusion pump 1 includes a drive motor 61, a liquid delivering drive unit 60 that delivers drug inside an infusion tube by pressing an infusion tube 200 on account of a rotor of the drive motor 61 in forward rotation, a rotational direction detection device 700 that generates detection information 780 regarding a rotational direction for judging whether the rotor of the drive motor 61 is in the forward rotation or reverse rotation, and a control unit 100 that judges whether a rotor 161A of the drive motor 61 is in the forward rotation or the reverse rotation based on the detection information 780 regarding the rotational direction obtained from the rotational direction detection device 700.