Patent GB-521326-A (GB)
Title: Machine for raising spines from metal stock
IPC: B21C37/20
Filed: 1939-03-30
Abstract: 521,326. Making spined tubes &c. DEHN F. B. (Thermek Corporation). March 30, 1939 No. 10030. [Classes 83 (ii) and 83 (iv)] Barbing by cutting. In'a machine for cutting and raising spines on metal stock such as a tube 31 for a heat exchanger, the successive edges of a rotary cutter cut the spines 30 from the wall of the tube and push them into a raised position, the cutter having a planetary movement round .the work which is fed axially to form a helical series of spines as shown in Fig. 16. The cutters have a number of helicallyarranged blades c and the edge c<SP>2</SP>, Fig. 18, of each cutting blade starts the cut on the work on the leading side of the element at the point 32 and cuts deeper into the work towards the trailing side c<SP>4</SP> where the cut is terminated leaving the spine attached to the work the wall of which is not perforated. The face c<SP>1</SP> and the rounded portion c<SP>5</SP> of the blade push the spine into a raised position so that it clears the cutter. The successive cuts may overlap both circumferentially, Fig. 24, and longitudinally, Fig. 17. In a machine embodiment two planetary cutters b are arranged on opposite sides of the work. The machine frame has a number of cover plates a<SP>1</SP>-a<SP>6</SP> to facilitate access to the gearing. A pulley d driven from a motor 25 drives a main shaft d<SP>1</SP> geared to a countershaft d<SP>4</SP> connected by bevel gears 53, change gears 56, worm gearing 60, vertical shaft 61, and pinion 62 to gears 51 on the feed rolls. The feed rolls rotate on bearings 50 on eccentric portions 47a of stud shafts 47, these shafts being adjustable to vary the grip of the rolls on the tube. The speed of the feed rolls may be adjusted through the change gears 56 to vary the pitch of the helix on which the spines are cut and the feed rolls may be changed for feeding tubes of different sizes by removing them from driving pins 52a mounted in the gears 51. The planetary carrier e of the cutters is mounted in bearing rings 71, 73 at its enlarged forward end and the rear hub portion carries a ring e<SP>3</SP> running in a bearing 75. The carrier is driven from the countershaft d<SP>4</SP> through pinion 77, and ring gear 80. The cutter heads b are centred by conical studs and secured to shafts 81 journalled in pivoted arms f each of which consists of two connected parts fulcrumed to the carrier by a boss 88 and a stud 89 carried in a cover plate e<SP>6</SP>. Gears e<SP>7</SP> are carried on the cutter shafts 81 and are connected to a gear 97 on the shaft d<SP>4</SP> through gearing 98 gear ring 100 rotatable on the carrier, internal teeth 108 on the gear ring, gears 105 concentric with the fulcra of arms f, and gearing 107. The arms f are adjusted to set the cutters at the required radial distance from the work axis by pairs of screws 96 coacting with pins 94 on the parts f<SP>1</SP>. The gears 97, 98 are change gears located under a cover a<SP>5</SP> for varying the number of spines cut per revolution of the work and for lowering the cutting speed for cutting hard metals such as steel. An air blower g is provided for cooling the cutters. The blower is driven from a motor g<SP>1</SP> and delivers air to a space g<SP>5</SP> adjacent the cutters. Thence the air passes along the pipe 31 and also around the gears within the carrier e. Adjacent the cutters the work is guided by a collet h<SP>1</SP> mounted in a taper bored sleeve h. Axial springs h<SP>3</SP> tend to close the collet on to the work. An oil pump k for lubricating the gearing is driven from the shaft d<SP>1</SP> by a chain k<SP>1</SP>.