Ventilator, small animal, valve head & drive.
Accession #: 2008022 (head); 2008023 (motor & gearbox)
Description: This mechanism, driven at various speeds by a multi-diameter drive belt system, uses a piston and a linked valve mechanism to deliver a predetermined tidal volume with a distorted half sinus flow pattern. The tidal volume is adjusted between 0 and 26 ccs. by changing the effective length of the crank by means of the threaded control in the foreground. The mechanism is driven by an electric motor and gearbox assembly that is illustrated separatel. Both would have been mounted on a frame and linked by a drive belt. It is classified as a time cycled variable flow generator. Manufactured by Harvard Apparatus Ltd., Fircroft Way, Edenbridge, Kent.
The motor and gearbox assembly is built by Parvalux and has a nominal shaft output speed of 56 rpm that is delivered to a multi-diameter 4-part pulley wheel. A drive belt between this pulley and the matching one on the ventilator valve head offers the opportunity to change speeds my manipulating the belt between levels of the pulleys. Manufactured to insulation Class B, BS 5000 Part 11 by Harvard Apparatus Ltd., Fircroft Way, Edenbridge, Kent. Catalogue #: 50-1718
Dimensions: Piston head: 325 x 150 x 140 mm; drive: 255 x 180 x 160 mm