Patent GB-508630-A (GB)
Title: Improvement in hydraulic presses
IPC: B21D15/10
Filed: 1938-08-09
Abstract: 508,630. Corrugating tubes. FULTON SYLPHON CO. Aug. 9, 1938, No. 23485. Convention date, March 30. [Class 83 (iv)] Stamping.-In corrugating a tube by closing together the hinged halves of spaced collar dies and applying hydraulic pressure to the inside of the tube to bulge out the metal free of the collar pressure, the open end of the tube is automatically sealed by a piston-moved stopper, after the collar halves are locked together, whereupon a pressure booster automatically applies the internal pressure. After the preliminary bulging as in Fig. 15 a second piston withdraws the spacers from between the collars, which starts a ram to apply axial pressure to crowd the bulges and the collars towards each other so forming a corrugated tube. The compression of the collars actuates a pilot valve to remove the internal bulging pressure and unseal the tube end. When a tube 139 is placed in position, hand operation of lever 72 clockwise, Fig. 9, hinges the cradle 34, carrying the halves 36 of the collars to bring one set of halves to the other set, whereupon latches 50, Fig. 8, drop over tongues 51 on plates 36 and latch fingers 60, Fig. 9, engage in recesses at the top. As the cradle 34 thus reaches its locked position it operates lever 239-238 of a pilot valve 104, Fig. 13, the piston rod 107 of which moves clamp 119 so that the valve member 137 enters the tube, and clamp fingers 136 grip the tube. Further motion forces the tube against closure 137 to form a fluid tight joint. Fluid through valve 162 passes to booster 165. where it creates a higher pressure in the cylinder 176 which high pressure presses, through check valve 182, on piston 170 until piston 170 can no longer raise the plunger 171 in 176 so that pressure fluid passes through conduit 185 to 184 to open valve 183. At this time the tube ends have just been sealed so high pressure from cylinder 176 through 188, 130, 137 passes into the tube 139 to bulge in between the collars 29, 36. A pressure relief valve 186 drains off the excess fluid pressure to press on valve 200, opening valve 196 and then opening 200, allowing free exhaust from relief valve 186 to maintain constant the pressure in tube 139. As soon as valve 196 is opened, pressure fluid from 157 through 202 passes to raise plunger 205 and rotates arm 99 counterclockwise, Fig. 6 moving slide 85 to left and withdrawing the spacers 92 from between the collars 36 after which valve 200 opens and valve 196 closes. As slide 85, Fig. 6, moves to left, it moves arm 86 over cam 213 to depress plunger 212 to open valve 209 admitting pressure fluid to cylinder 16, Fig. 1, forcing its piston and ram 21 to move the collars nearer each other against the action of intermediate springs 45 thus corrugating the tube by-forcing its bulges into the recesses 411 and 42 of each pair of half collars 29, 36. At the end of this axial compression a finger 244 moves a bracket to the left and rotates pilot valve handle 238 to supply pressure fluid to the bottom of a fourway valve 155 which connects fluid pressure to move back to the right the piston cylinder 16 thus withdrawing the compressing ram 'from the end plate 246. At the same time fluid from conduit 215 passes into the top of the booster cylinder 165 and forces down the piston 170, Fig. 19, and plunger 171 moves down in cylinder 176 allowing supply water from main to fill 176 for the next cycle. Meanwhile fluid from conduit 215 forces piston 104 to the left drawing clampers 119 to the left disengaging the surface 124 from 136 and allowing fingers 135 to release the now corrugated tube. Clamp 119 continues to move to the left until the closure 137 is pulled out of the end of the tube 139 and the tube end sealing assembly is returned to its 'initial position. Counterclockwise hand rotation of lever 72, Fig. 9, starts pivot 76 down slot 75 and moves shoulder 82 away from under 73. Thereafter springs 69 rotate cradle latch 67 clockwise which frees fingers 60 from recesses', frees pin 61 from fingers and opens latches 50 so unlocking each half collar plates 29 and 36 and rotates cranks 67 releasing the tension in the springs 69. Further hand movement of 72, 73 rotates cradles 33, 34 , and separates each pair of collars and the operator then removes the finished tube. He then depresses locking lever 248, disengaging rod 247 and allows springs 45 to force the collars apart axially to their initial positions. Hand rotation of lever 98 clockwise, Fig. 6, closes valve 209 and inserts spacers 92 between the collars and allows hand rotation of lever 238 to rotate pilot valve 235 to its initial position.