Patent GB-102269-A (GB)
Title: Flexible Tubes and Apparatus for Making same.
Inventor: BRINKMAN LOUIS HERMAN
IPC: B21C37/12
Filed: 1916-11-17
Abstract: 102,269. Brinkman, L. H. Nov. 18,1915, [Convention date]. Cased or compound forms; pipes.-Relates to the construction of, and apparatus for making, flexible tubes from a. strip or ribbon of metal. The strip is composed of two or more layers of the same or different materials, and is given a longitudinal fold or groove before being helically wound into the form of a tube with the edges of adjacent convolutions interfolded. In the form shown in Fig. 10, the strip consists of two layers 98, 99 of brass with a transversely tapering layer 102 of steel interposed, the layer of steel being of less width than the brass, so as not to extend into the seam formed by the interfolded edges of brass. Fig. 14 shows a modification in which only two layers 101, 102 are employed, the inner layer 102 preferably being of spring brass. The apparatus for making the tube comprises a rotary spindie B, Fig. 1, formed in one with a screw rod E, and a die F which co-operates with the screw-thread 28<1> of the rod to form the strip into a tube. The die F, Fig. 6, consists of an outer metal casing 29, a metal bushing 31, and the die proper 30 having tube-forming threads 38, 39, 40, conforming threads 35, 36, 37 and unthreaded clearances 78, 79. The strip of metal passes to the rotary rod E through a preliminary former 45<1>, Figs. 3 and 5, which forms the fold or groove and also bends over the edge 46, and thence through an opening 43 in the casing 29. The strip is frictionally gripped by the screw-thread 28' and is carried round with it, the die F at the same time receiving a longitudinal movement. As the strip first enters the die, the groove coincides with the top of the thread 40, and the sides 47, 48 of the strip lie against the walls of the thread. The strip then passes through the tube-forming threads 38, 39, 40, which are shaped so as gradually to interfold the edges of adjacent convolutions and bend them into a final condition, indicated at 59, Fig. 7. When the die F has reached the limit of its tube-forming movement, the direction of rotation of the screw rod E is automatically reversed, thus releasing the frictional grip between the metal strip and the thread 28<1>, and allowing the die F and the portion of the tube already formed to move back to its initial position to re-commence a second tube-forming movement. The reversing is effected by means of a longitudinally-moving nut G operating, through links 25, levers 17, and forks 10, a clutch C splined on the spindle Band adapted alternately to engage oppositely rotating pulleys 3, 4. After passing through the forming die, the tube is pressed by means of rollers 60, 61, Fig. 3, which may at the same time give a crimp to the seam, as shown in Fig. 14. The longitudinal section of the completed tube may be that shown at 59, Fig. 7; or, by applying endlong pressure, the walls of the groove may be reflexed and the completed tube have a section as shown at 95. Specification 101,418 is referred to. Reference has been directed by the Comptroller to Specification 21076/02.