Felt tubular filter for fuel - has longitudinal joint bonded by thermoplastics applied hot then rapidly cooled

摘要

A tubular felt filter is made by bending around a flat blank of the felt sheet into a cylindrical shape and gluing the abutting edges together. Liquid thermoplastics is applied as a thin strip of adhesive from a nozzle along the generator in which the joint of the tube lies thus covering the joint. The nozzle and the tube are moved relative to one another, e.g. the nozzle is stationary and the tube is moved. After the position at which the adhesive thread is applied, it is immediately cooled by cooling roller and pressed onto the felt. Pref., the cooling and pressing take place simultaneously, e.g. the roller is spring-loaded; in addition, further pressing may be applied immediately afterwards, esp. by a spring-loaded block. The adhesive is continuously applied in a simple manner and is immediately rapidly hardened by cooling and pressing on.