Biopsy injector batch testing of trigger spring strength

Case study

Biopsy gun spring strength [PDV10011]

Biopsy spring force graph

Solution

Multitest-i (now OmniTest) computer-controlled test system
Custom fixture to to quickly engage and release the test specimen

Benefits

Independent, in-house, testing
Confident that their medical device is functioning to specification

The performance to standard of our biopsy devices is critical, and our MultiTest systems enable a rapid and accurate assessment of every one. The repeatability of the test cycle, and above all the traceability of each unit under test, gives us the guarantees we need.

Cliff Price, Director Technical Services
Bard Ltd

Requirement

Bard Limited (a UK division of C R Bard Inc.) services Bard® Magnum® biopsy needle injector guns for clients around the world. A prime component in the reusable handheld device is a powerful spring with a dual-action trigger for taking the biopsy sample. Primed by single-finger pressure, the resistance as the cocking slide locks the compressed spring in place must be within design specification. It cannot be too strong for the user’s finger, nor too weak to perform a full, effective insertion and withdrawal. Bard have defined tolerances for the force required to cock the gun, and needed a device to measure each unit for continued compliance.

Solution

Mecmesin supplied two MultiTest 1-i test stands, each with a custom-designed grip system for the sample. The gun under test is quickly clamped into a secure position, while an upper stirrup engages the cocking slide. Emperor™ software has been programmed to run batches of tests, displaying real-time characteristic graphs and instant green/red pass/fail indicators. Each unit is referenced, and all results are stored for analysis and reporting. The new equipment enables a rapid throughput, consistent testing and accurate reporting, saving Bard significant time and money.

The current OmniTest UTM range now fulfils this solution. In the medical sector, VectorPro software has security modules built on robust architecture to enable organisations to meet FDA 21 CFR Part 11 compliance for electronic signatures and records.