Conical Pipetting Needle Holder for Automated Analyzer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current pipetting systems in automatic analysis devices face challenges with precise positioning and frequent needle replacement, leading to potential crashes, errors, and the need for extensive readjustment, which is time-consuming and prone to inaccuracies.
Innovation Solution
A pipetting device with a fastening body designed as a truncated cone, allowing for exact positioning and secure attachment to a conical holder, eliminating the need for frequent readjustment by ensuring the needle's consistent position upon replacement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a pipetting needle is manually adjusted using gauges and wedge bearings, then the needle position can be adjusted, but the adjustment process is time-consuming, error-prone, and requires specially trained service technicians
Solution Approach 1:
The needle is pre-adjusted to the correct position during manufacturing with high precision. The conical fastening body is designed with a specific cone angle that ensures the needle tip aligns perfectly with the vessel opening when inserted into the conical cavity of the holder. This preliminary adjustment eliminates the need for time-consuming on-site calibration by trained technicians.
Solution Approach 2:
The conical fastening mechanism enables the needle to self-align and self-adjust to the correct position simply by being inserted into the conical cavity. The geometry of the cone automatically positions the needle tip at the correct height and angle, allowing any user to perform the adjustment without specialized training or tools.
2Reliability
If a pipetting needle is replaced frequently due to wear from piercing vessel closures, then the consumable part can be renewed, but the needle tip position deviates and requires extensive readjustment
Solution Approach 1:
The conical fastening body and cavity are manufactured with precise geometric tolerances to ensure that every new needle automatically aligns with the correct position when inserted. This preliminary precision engineering eliminates the need for complex adjustment procedures after needle replacement, maintaining simplicity while ensuring reliability.
Solution Approach 2:
The conical geometry with a specific angle (e.g., 60 degrees) transforms the adjustment parameter from a complex multi-dimensional alignment problem into a simple insertion action. The cone angle is designed to compensate for any minor variations in needle manufacturing, automatically bringing the needle tip to the correct position regardless of small deviations in the needle body.
3Strength
If the needle is secured using wedge bearings with set screws, then the needle can be fastened, but the mounting is not stable and the needle may slip out during operation
Solution Approach 1:
The conical fastening body and cavity provide a curved geometric interface that distributes mechanical stresses evenly around the needle shaft. This curved contact surface prevents stress concentration points that would cause the needle to slip or become loose during operation, providing both strong fastening and long-term stability.
Solution Approach 2:
The fastening system combines the conical geometric interface with appropriate material selection for the fastening body, holder cavity, and needle materials. This composite approach ensures compatible friction coefficients and mechanical properties that maintain stable fastening under the high forces involved in piercing vessel closures repeatedly.
4Ease of operation
If the needle tip position is adjusted by eye using frame struts as reference points, then the adjustment can be performed without specialized tools, but the method is error-prone and cannot achieve sufficient precision
Solution Approach 1:
The conical fastening geometry is pre-engineered to provide automatic mechanical alignment when the needle is inserted into the holder. This eliminates the need for visual estimation or manual alignment by the operator, achieving both ease of operation (simple insertion) and high precision (automatic geometric alignment) simultaneously.
Data Source
Figure 1~2
Figure 3~5
Figure 6
AI summary
The invention relates to a pipetting device (1) for an automated analyzer, which is particularly stable and allows for easy and error-free replacement of the pipetting device (1) and thus particularly reliable operation of the analyzer. For this purpose, a substantially frustoconical mounting body (6) is arranged around an axial region of the needle body (2).