Type 1 diabetics are dependent on the steady flow of insulin. Portable insulin pumps allow an active, mobile life and can increase the quality of life of patients. The Swiss medical technology specialist Ypsomed is introducing a new pump known as the “mylife YpsoPump” into the European market. With a weight of just 83 grams—including the battery—and a thickness of just 16 mm, it is compact and comfortable to carry. The proven “Lube & Seal” concept from Freudenberg Sealing Technologies and lubricant manufacturer Klüber Lubrication, which is part of the Freudenberg Group, ensures the pump’s flawless functioning over its four-year lifespan. It aims at the perfect interaction of seal and lubricant.
Portable insulin pumps continually transport vital insulin into the patient. The dosing must be precise down to the microliter to keep the patient’s metabolism in balance. This is guaranteed by the extremely precise functioning of the new pump’s drive, which pushes a punch into the replaceable insulin carpule. The distance covered determines the delivery volume. A separately measured blood sugar level is the basis for controlling the pump. The target-actual comparison employs various parameters, which are measured within the pump itself—especially based on a force measurement within the drive. To facilitate a reliable measurement, as little friction as possible among all the drive’s components is important. This poses a major challenge especially for the feed seal. A rod seal seated on the driveshaft (threaded sleeve) for the punch seals the interior operation of the drive toward the carpule space and protects against the penetration of dirt particles or water.
Freudenberg Sealing Technologies was able to resolve the contradiction between minimal friction and high leak tightness with the combination of an innovative seal and a high performance lubricant from Klüber Lubrication. The rod seal also has a smooth, low-friction surface. A nanotechnology process developed by the company reduces roughness and decreases the tendency of the elastomer to adhere more strongly to the threaded sleeve when the device is stopped. This design allows even torque progression.
The already low frictional torque—four thousandths of a Newton meter— can even be cut in half with the application of a PFPE lubricant. PFPE stands for perfluorinated polyether oils, whose stability is significantly superior to that of conventional lubricants even under extreme conditions—they are even used in space flight.
Freudenberg Sealing Technologies
fst.com
Filed Under: Seals • gaskets • O rings, Medical-device manufacture, MORE INDUSTRIES, MOTION CONTROL