| 摘要 |
A method of making a liquid filter includes the steps of providing a spiral roll of filtering material on a central tubular member, providing a housing member into which the roll is to be placed and laying a bead of thermoplastic material having a given softening point on an outer surface of the roll at least around the circumference of the roll close to an end thereof. The bead is pressed with cooled forming jaws, while in a warm state, to suitable dimensions corresponding to inside dimensions of the housing member. The housing member is heated to a temperature above the softening point of the thermoplastic material, the roll is inserted into the housing member and thereafter, the housing member is cooled. The thermoplastic material cools, acts as a glue and constitutes a tight, rigid connection between the housing member and the roll of filtering material. |
