| 摘要 |
625,672. Extruding fuzes etc.; apparatus for manufacture of fuze cords. SOC. p.a. LAVORAZIONE MATERIE PLASTICHE. May 2, 1946, No. 13342. Convention date, Oct. 4, 1944. [Class 87 (ii)] [Also in Group XXI] A safety fuze is provided with a sheath of synthetic thermo-plastic material reinforced with longitudinal threads of synthetic material of high tensile strength and low elasticity incorporated in the sheath. An explosive charge 1 forming the core of the fuze is fed under pressure through an axial bore 7 in an extrusion head 10 to be coated with the plastic material 2 on emergence. Longitudinal reinforcement threads 3 are simultaneously fed through the head 10 to become embedded in the plastic material 2. The plastic material 2 is fed by a screw press, fixed at 6, into an annular chamber 4 surrounding the bore 7 and communicating with an annular pressure die 5 concentric with and surrounding the bore 7. The material 2 is distributed throughout the chamber 4 by a bush (not shown) described in Specification 624,699. Nylon threads 3 are threaded through longitudinal holes 8, equally spaced round the circumference of a circle of diameter equal to the mean diameter of the die 5. The threads 3 emerge from the die embedded in the material 2 which is drawn into cylindrical form contracting as it cools to exert a slight pressure on the explosive. The material 2 may be a polymerization product of vinyl compounds, acryl, styrol compounds and the like or softened cellulose acetate or ethylcellulose compounds. |
