Automatic Dispensing Device With Force-Controlled Tip Attachment

Solution Overview

Problem

In automatic dispensing devices, variations in the position reproducibility of the robot arm and dimensional errors lead to inconsistent fitting depths of pipette tips on the nozzle, causing either insufficient attachment or mechanical damage during liquid handling processes.

Innovation Solution

An automatic dispensing device equipped with a gripper, a tip rack arrangement portion biased by a compression coil spring, and a moving unit that ensures the discharge nozzle is pushed into the pipette tip with a constant force, maintaining a consistent fitting depth by moving the gripper and tip rack arrangement portion together.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the robot arm is controlled to lower the dispensing pipette by a predetermined distance to mount the pipette tip on the nozzle, then the attachment process is simple and efficient, but the fitting depth varies due to position reproducibility limits and dimensional errors, causing insufficient attachment or mechanical damage

Engineering Contradiction:

Improveattachment efficiencyVSAvoidfitting depth consistency

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The invention changes the control parameter from fixed distance to fixed force. The moving unit applies a predetermined constant force to push the discharge nozzle into the pipette tip, replacing the traditional fixed-distance control method. This force-controlled approach ensures consistent fitting depth despite variations in component dimensions or robot arm positioning accuracy.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention introduces a force control mechanism as an intermediary between the moving unit and the attachment process. This intermediary controls the pushing force applied to the discharge nozzle, ensuring that the nozzle is inserted into the pipette tip with a constant force. This force mediation resolves the contradiction by decoupling the attachment quality from positioning precision.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Device complexity

If the robot arm lowers the dispensing pipette by a fixed predetermined distance, then the control is simple, but dimensional errors of the pipette tip and tip rack cause variation in fitting depth

Engineering Contradiction:

Improvecontrol system complexityVSAvoidfitting depth consistency

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The invention changes the control parameter from fixed distance to fixed force. The moving unit applies a predetermined constant force to push the discharge nozzle into the pipette tip, replacing the traditional fixed-distance control method. This force-controlled approach ensures consistent fitting depth despite variations in component dimensions or robot arm positioning accuracy.

Inventive Principle:

Principle #35Parameter changes

3Ease of operation

If the robot arm positioning precision is limited, then the device is easier to manufacture and operate, but the bottom position of the nozzle and distance to pipette tip vary, causing attachment failures

Engineering Contradiction:

Improveoperation simplicityVSAvoidattachment reliability

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The invention changes the control parameter from fixed distance to fixed force. The moving unit applies a predetermined constant force to push the discharge nozzle into the pipette tip, replacing the traditional fixed-distance control method. This force-controlled approach ensures consistent fitting depth despite variations in component dimensions or robot arm positioning accuracy.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention introduces a force control mechanism as an intermediary between the moving unit and the attachment process. This intermediary controls the pushing force applied to the discharge nozzle, ensuring that the nozzle is inserted into the pipette tip with a constant force. This force mediation resolves the contradiction by decoupling the attachment quality from positioning precision.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 configuration ensures consistent attachment of pipette tips to the nozzle, preventing mechanical damage and ensuring accurate and precise liquid sampling or dispensing by maintaining a constant fitting depth, thereby enhancing the reliability of liquid handling operations.

Implementation Method 1

a biasing member configured to bias the tip rack arrangement portion from below

Methodology Applied

Scientific EffectElastic force: Elasticity

Data Source

PatentUS20240082848A1Automatic dispensing device

Publication Date: 2024.03.14 SHIMADZU CORP

AI summary

An automatic dispensing device includes a gripper configured to grip a dispenser having a discharge nozzle with the discharge nozzle facing downward, a tip rack arrangement portion configured to arrange a tip rack in which pipette tips to be attached to the discharge nozzle are accommodated, a biasing member configured to bias the tip rack arrangement portion from below, and a moving unit configured to move the gripper relative to the tip rack arrangement portion.