Patent GB-486002-A (GB)
Title: A method of and means for shaping metal tubes or containers
IPC: B21D22/18
Filed: 1936-09-25
Abstract: 486,002. Tube expanders. DOVE, J. A. Sept. 25, 1936, No. 26019. [Class 83 (iv)] Apparatus for shaping metal tubes or containers by expanding or bulging comprises, in combination, means for supporting the work, a rotating tool having one or more shaping elements which are displaced radially outwards to apply pressure to the interior of the work, means for effecting longitudinal movement of the work simultaneously with the rotation of the tool, and means to control automatically the outward displacement of said elements. A machine for shaping a container 19 by rollers 34 comprises a headstock 11 constituted by brackets 17, 18 which are slidable on bars 13 longitudinally of the stationary tool 12 by a rack and pinion. Screwed sleeves 24 enable the headstock to be adjusted to receive different sizes of work. The bracket 18 has a central aperture for the passage of the tool 12, and comprises a spigot 26 which receives one end of the container which is retained by a spring ring 27. The other end of the container is similarly received in a sleeve 28, which is mounted on a boss 29 by a pin-and-slot connection enabling it to be rapidly advanced or retracted for the insertion or removal of a container. One of the members engaging the ends of the container is milled or knurled. The balls 34 of the tool may fly outward under centrifugal force to a position limited by a stop or as illustrated, are moved positively outward by axial movement of a ring 37 and are returned by a spring-loaded roller 38. The ring 37 is moved by a rod 39 actuated by a cam 41 which is moved transversely of the machine by an adjustable chain 42 passing over pulleys and connected to the headstock. The rollers are thus displaced radially in agreement with the movement of the headstock. Adjustable stops 48, 49 limit the travel of the headstock in one direction, a further stop being provided at the opposite end of the machine. The cam 41 may be adjusted towards the headstock after one traverse to produce further expansion of the work by movement of a wedge 50 which slides on an inclined surface 51, this movement being produced by a handle 52 carrying a pin 53 engaging a pin 54<1> of an adjustable abutment on the member 50. To avoid cutting the work between the balls and the edge of the clamping sleeve in this second operation, the headstock is moved away from the work by a small amount, the handle 52 being adapted, for this purpose, to rotate the stop bar 49, this bar carrying a ramp 57 engaging a fixed ramp 58 to move the bar against the action of a spring 56. The tool is rotated by a motor mounted on the machine. In a modified machine which is arranged vertically, the headstock 111, Fig. 3, slides on bars 113, 114, the tool shaft being driven by a motor which also drives a crank-shaft 61 which reciprocates the headstock by means of a crank-pin 62 and a connecting rod 63. The headstock is counterweighted. The reciprocation is controlled by a clutch pedal 65 which, through linkage 66, 67, rocks a finger having an inclined face which moves the clutch to disengaged position. The control spindle 139 for the tool is moved by a cam 141 moved horizontally by a chain 142 from the cross-head. The cam has an inclined face slidable on the inclined surface of a member 151, and is moved thereon to adjust the height of the cam by a rack and pinion 75, 76. In a modification, at the commencement of each traverse a wedge is slid beneath the cam to determine its vertical position. In a further modification, a rotary cam is employed. A positive work clamping device, Figs. 3 and 5, adapted to grip or release both ends of the work simultaneously comprises a sleeve 28 as described above which is rotated to clamp the top of the container, the downward movement thereof depressing arms 86 and a ring 84, tapered surfaces on which move clamping segments 83 inwardly, against springs 82<1>, 87. A tool for use in either machine comprises rollers or balls 78, Fig. 5, mounted in carriages 77, diametrically opposed carriages being united by chains 79 which are adjusted by the rod 39, 391 to limit the outward travel of the rollers under centrifugal force. In a modified tool, the movement of the balls 34, Fig. 9, is positively effected or controlled by divergent prongs 92 on the rod 39, which pass through bores in the toolcarrying plungers 91. In a further modification, rollers are mounted on spring-pressed carriages which are moved radially by an enlarged extension on the rod 39. The working pressure may be applied by the ends 96<1>, Fig. 11, of levers 96, expanded by a sleeve 39<1>. Rollers may be fitted at the ends of the levers. An annular bulge at the end of a work-piece, as shown in Fig. 12, is produced by tools 98 actuated by the rod 39 against the action of counterweighted levers 99. A further form of tool, comprises balls 34, Fig. 14, traversed around a race of the same shape as the section of the container by a gear-wheel 101 on a rotary spindle 102. The position of the balls is varied by axial movement of a central member having an inclined face on which the balls run. Specification 486,083 is referred to.