Patent GB-1011699-A (GB)
Title: Apparatus for the manufacture of heat exchange tubes
IPC: B21C37/26
Filed: 1964-08-04
Abstract: 1,011,699. Making gilled tubes, coiling, brazing. F. ROFFELSEN. Aug. 4, 1964 [July 20, 1963], No. 30614/64. Headings B3A, B3E and B3R. Apparatus for making metallic heat exchange tubes which have wound helically thereon a wire helix of acircular cross-section which is secured to the external surface of the tube by a rectilinear or inwardly arcuate portion of each of its convolutions comprises driving means 2 to continuously rotate and simultaneously axially feed the tube 3 to be wound, a stationary winding device 9 for the wire helix 10 having a mandrel, stationary relative to the tube axis, which has a plane or arcuate peripheral surface oriented approximately tangentially to the tube periphery, a winding head which revolves about the mandrel axis and draws off wire from a stationary mounted supply reel 16 to wind it about the mandrel to form the helix and simultaneously slide the latter therefrom, a device 12 for supplying a solder band 13 and a heating device 15 to heat the tube and helix to effect the soldering together thereof. The tube driving means comprises three gear-wheels 32, having shouldered tooth crests 34 which form sharpened edges which engage the tube. The gears, which also engage a scroll on the end plate 33 of a rotatable housing 28 driven by a gear 27, are rotatably mounted on three radially adjustable jaws 31 of a chuck 30 rotatably mounted on the housing 28 and driven by gear 29. Rotation of the chuck 30 effects rotation of the tube whilst the gears engaging the scroll are rotated thereby to axially advance the tube. Rotation of the housing and the plate 33 in either direction serves to accelerate, decelerate or stop the rotation of the gears and hence the axial feed of the tube. The wire 11 is drawn off by the winding device 9 from a supply reel 16 and passes over a series of rollers 18 and a spring supported tensioning roller 21. A reel brake comprises a pivoted lever 20a, loaded by a spring 20b which is also coupled to a spring- loaded wire guide roller 18a such that when tension is applied to the wire the spring 19 lifts the lever to release the brake. The spring 20b, 24 tensions are adjustable by controllers 22, 23. The winding device 9 comprises a driven mainshaft 35, mounted in a bushing 42 in which is rotatably mounted a chuck 36 supporting a mandrel 37, the shaft 35 being positively coupled to the chuck by a gear train 47, 49, 48, 46 so that the chuck rotates at the same speed as the mandrel in the opposite direction and the mandrel is stationary relative to the outer stationary housing 43 and the tube 3. The wire 11 passes through a bushing 52 and a slot 53 to the shaft 35 over a roller 54 and an exchangeable plate 53 fixed to the shaft to be wound about the mandrel, a ramp 56 equal in height and diameter to the wire to be wound on the plate securing to continuously push the convolutions up and off the mandrel towards the feed tube and serving to draw the wire from the supply reel. The convolutions formed on the mandrel may be formed to the required acircular shape by one or more elements 57 radially slidable once per revolution towards the mandrel by an annular grooved cam track 58a formed in the top of the main shaft 35. Adjustment of the bushing 42 in the housing 43 adjusts the attitude of the helix leaving the mandrel 37 to the tube 3. A solder band 13 is drawn from a supply reel about the tube and an inductive heating coil 15 arranged about the tube and helix to effect soldering thereof. The finished tube is supported by a device 14.