Miniature Heat Torch for Blood Analyzer

A newly designed Blood Analyzing Instrument required a very specialized miniature air heater and very precise performance. No Instrument had ever performed a process like this and there had never been a heater like this.

Project and Challenges

Our client needed to develop a very small precision heat torch to make film cuvettes in real-time for blood storage and testing onboard the Instrument.

Our client had very little space for this cuvette making station and the heater had to fit the small scale of the cuvette. The heater needed to have a profile of about 1".

The heater needed to heat a flow of .4 lpm to 380° F within 3.5 seconds. A thermocouple would have to be integrated into this small space to indicate when the 380° F target temperature is obtained.

The heat torch would need to be field replaceable and snap out and back into place. This meant that wire leads would be awkward and of little use.

Solutions and Their Impact

Farnam helped design a heater that has less than the desired 1" profile.  Our heater fits the package perfectly. The closest heater our client had been able to find was 400% larger.  We consistently achieve the 380° F rise in 3.5 seconds or less  and we built a test station to verify all production meets this standard.  A very small exposed thermocouple is integrated into the exhaust diffuser and is sensitive enough to give accurate and fast updates.