314,843. Still, W. J. April 3, 1928. Tubes. - In a machine for making heat radiating elements wherein a wire spiral is formed and wound round a tube, the spiral forming wire is taken directly from a swift and passed through a rotary member and then wound on to a stationary mandrel of the cross-section of the spiral to be produced. The binding wire b<1> within the wire spiral is drawn from a spool b<2> mounted in a stationary frame b, the spool shaft having brake discs b<3> engaged by brake members b<12>, b<15> carried on levers b<5> pivoted at b<6> to a rocking frame b' on a shaft b<8>. The rocking frame is controlled by springs b<9> around studs b<10> and adjusted by nuts b<11> to give the right amount of drag on the wire by the wedging action of the rollers b<13>, b<18> on the backs of the brake members b<12>, b<15>. The binding wire passes from the spool b<2> along a groove a<7> in the stationary mandrel shaft a<1> to the mandrel a. The spiral forming wire d is drawn direct from the swift a<2> and passes through a long guide channel c<8> on a rotating carrier C thence through the driven rotary member c<6> over a guide roller c<12> to the coiling rollers c<13>, c<20>, Fig. 3, on the rotary head c<23> which forms the spiral on the mandrel a; the wire d passes from the guide channel c<8> to the rotary member c<6> through a guide c<11> in a connecting member c<5> located in the angle of a swashing gear i working on a ball i<2> keyed to the mandrel shaft and engaging a fixed gear i<1>. A long weightsupported loop is provided in the spiral wire d between the swift and the rotary carrier C to enable the heavy swift to be started by the slight tension on the wire without breakage of the latter, the wire being carried upwards over a pulley n<2>, Fig. 11, on a slide n<4> moving on a guide n<5>. The slide n' is connected to a rope D secured to a pulley n<6> to which is fixed another pulley n<18> connected by a rope D<1> to a quadrant r on a shaft a<16>; the weight n<7> is hung on the sector by a rope D2. On starting the machine the pull on the wire d causes the pulley n<2> to descend and shortens the loop whilst the swift is gradually speeding up. A spring D3 is interposed between the rope D and pulley slide n<4> to even up shocks. The length of loop controls the unwinding of the wire from the swift by brake mechanism shown in Figs. 7, 11, by means of a Bowden wire m<20> attached at one end to a rocking member A15 on the quadrant shaft a<16> and at the other end to a lever m<17> linked to a lever m<1> actuating a brake band m<9> such that shortening of the loop causes an upward pull on the rope D' releasing the Bowden wire m<20> and brake band m<9>, allowing the swift to speed up, and vice versa. The wire passes from the swift to the looping mechanism through a staple m moving on a pivot m<1> and operating an arm m<2> influenced by a spring rod m<6> whereby in the event of the wire jamming on the swift, as shown in chain lines, Fig. 7, the kink formed in the wire pulls on the staple m which is then shot over by the spring rod m<6>; the staple m being linked to the brake lever m<14> by a link m<16> thus applies the brake suddenly to the swift. At the same time a Bowden wire m<5> attached to the arm m<2> and linked to the Bowden wire apparatus controlling the starting handle of the machine brings the latter to a stop. The delivery of the wire coil from the mandrel a is facilitated by a swashing plate s, Fig. 4, rocked on a ball a<10> by an inclined faced bush s<1>. The tube T on which the wire spiral is to be wound in continuously rotated and traversed by a carriage A<40>, and is cleaned on its entry into the machine by a rotary scratch brush. Soldering. The wire spiral is soldered to the tube by wire solder supplied from a spool and wound on the tube between the turns of the spiral. Milling-machines. A contact surface is formed on the wire spiral by a milling cutter A<20> driven by spiral gear in a casing A<21> and pressed against the wire spiral by a spring, the angle of the spiral gear being so arranged that the cutter moves back against the pressure of the spring if it tends to dig into the spiral. Stop-motions. The driving gear is thrown into operation by a starting handle A, Fig. 9, which raises a weight supported by a band B, Fig. 7. The handle is kept down by a detent A<2>, which is withdrawn to allow the handle to return to the off position if certain conditons prevent satisfactory operation of the machine, viz. length of tube completed, wire loop too long or short, spiral forming wire d broken, jammed or exhausted, solder wire broken or exhausted. A cord A<13> extending the length of the tube carriage has a stop engaged by an arm on the tube carriage at any desired position whereby when the winding of the tube is complete the cord is pulled, shaft A<4>, Figs. 9 and 10, is rotated and a stud A<30> thereon tilts a spring-pressed arm A<5> so that a detent on the arm moves away from the detent A<2> on the member A<3>, thus releasing the starting handle and stopping the machine. Too long or too short a loop in the wire d swings the quadrant r, causing projections A<6> or A<7> on rocking member A<15> to engage a roller A<8> and depress a rocker A<17> connected by a rod W<3> to the release arm A<5>, and if the wire is exhausted the rocker A<15> is actuated in similar manner. If the wire jams the machine is stopped without waiting for the undue shortening of the loop by the action of the staple m, Fig. 7, and arm m<2> pulling the Bowden wire m<5> attached to arm A<10> on shaft a", thus operating rollers A<8> on rocker A<17>. The weight of the solder wire spool acts on another arm on the shaft a<16> to stop the machine if the solder wire is exhausted, and the arm A<5> may be actuated also by a hand release. When the required length of wire spiral has been wound on the tube the rotary member c<6> is stopped, and a length of binding wire or.ly wound on the tube and fastened by a clip.