Vauth-Sagel Systemtechnik GmbH & Co. KG

Production of the Interface Heating Plate for Anaesthetic Devices

Heating Plate
This component – with the highest-possible function integrity – is used in anaesthetic devices.

To establish itself as a supplier to the medical technology industry, a company must bring both above-average quality standards and – above all – a sense of responsibility to the table, as medical technology is frequently used to save lives. Manufacturers of medical technology and rehabilitation/care products do not just distribute technical articles, they also dispense care and safety. Here, Vauth-Sagel believes that it has – as a supplier – a high degree of joint responsibility for the reputation of its customers and regards their requirements as a daily benchmark.

The “Interface Heating Plate” project is a great example of Vauth-Sagel’s work in medical technology, as it focuses on a highly-complex product with state-of-the-art function integrity for deployment in anaesthetic devices. To this end, the heating plate forms the interface to the patient unit with fast coupling-type connections for gas-bearing systems and electronic sensors.

As the interface heating plate contains heating elements for heating respiratory air when used, it must – for the entire life of the device – offer high dimensional stability and the lowest possible tendency to warp. To ensure this in the long term, Vauth-Sagel chose to use 40-percent fibre glass-reinforced polyphenylene sulphide (PPS GF40) in the development of this device.

Even before the tools were designed, state-of-the-art simula-tion processes were used to analyse both the mould filling by means of cascade controlling the needle valve nozzles and the anticipated warping behaviour of the special material. The find-ings subsequently formed an important foundation for the de-sign of the hot channel, of the choice of injection methods and of the dimensional tolerances within the tool. To secure the en-tire manufacturing process, Vauth-Sagel integrated two toolinternal pressure sensors and reprogrammed the machine control so that the machine is controlled by these sensors.

Tuning the part to neighbouring components within the product’s module was carried out while creating the tools. To this end, this is about patterning with as yet still incompletely provided contours directly following the activation of the secured process. After complete three-dimensional measurement, these were finally placed in warp-compensated positions.
In the case of the interface heating plate, this is the largest injection-moulded component ever manufactured from PPS GF40. Here, the special challenges are both the tool temperature of 180 °C and the tremendous flowability of the raw material.