Patent GB-956484-A (GB)
Title: Improvements in or relating to a boring machine
Inventor: SPENCER RONALD BRUCE
IPC: F27D25/00
Filed: 1961-07-27
Abstract: 956,484. Boring machines. GUY F. ATKINSON CO. July 27, 1961, No. 27263/61. Headings B3B and B3C. In a boring machine for removing metal which has been refined in a reactor 20, the rotatable boring tool 116, Figs. 1, 2, is carried by a carriage 27, the reactor is clamped in a trunnion 25 by a clamp assembly 26, and a vacuum operated hopper 243 is engaged with the end of the retort which allows tool 116 to pass therethrough, and removes the metal bored out from the reactor. Trunnion 25, Figs. 4, 5, 5A, comprises a pair of cradle members 35 forming a seat for rounded bottom 21 of the reactor, and an annular frame 37 which is journalled at 38, 39 in bearings 40 mounted on stationary supports 42. Trunnion 25 is pivoted by a reversible motor 50 which drives a pinion 45 through a reduction unit 51 and a brake 52 the pinion driving a gear wheel 44 on journal 38. Dogs 55, 56 on wheel 44 engage limit switches 57, 58, to stop motor 50 and set brake 52, when the reactor is in a horizontal working position and a vertical loading position respectively. The reactor is clamped by power operated clamps 62, and hand operated clamps 63 in frame 37, the clamps having pointers and gauges for indicating position of the clamp when it engages the reactor. Further hand operated clamps 82 are carried by a transverse frame 80, Fig. 9, and a pair of manually adjustable fluid pressure operated toggle clamps 84 are also carried by frame 80. Carriage 27, Figs. 1, 2 and 3, comprises a transverse member 105, which slides on rollers 106, engageable with tracks 107, and is fed by two racks and pinions 108, 140. Tool 116 is carried by a support 112 on the carriage and is driven by a shaft 113. Rotation of tool 116 and feed of carriage 27 are accomplished by one of three motors 122-124. Motor 122 drives a speed change gear-box 125 which drives a bull gear reduction unit 129 including a gear 127 on shaft 113. Gear-box 125 also drives a feed change gear-box 130 connected to a gear-box 133 which drives through a clutch 135 and thence to a pair of downwardly projecting shafts 137, which carry the pinions 140 for engagement with racks 108. Motor 123 drives a shaft 145 connected to a further shaft 146 through a gear-box 147 and is connected to shafts 137 by a clutch 150. Motor 124 feeds carriage 27 during a scraping operation carried out by tool 116 prior to the boring operation and the drive is through shafts 152, 153, clutch 154 and gear-box 147. Tool 116 comprises a tube having a spiral fin 158 for removal of cuttings and a cutter head 120. The cutter head 120 is of hemispherical shape and has screwed thereto a number of spirally shaped bars 170 which carry square sectional tooth bits 175, Fig. 13, arranged in staggered relation so as to travel in overlapping circular paths and to remove equal volumes of material. Prior to the boring out of materials, Fig. 8, the inside wall of the top of the reactor is cleaned by scrapers attached to tool 116. The cutter head 120, Fig. 12, has two casings 202 secured therein and mounted in each casing is a sleeve 205, Figs. 16-19, non- rotatably held in the casing by a spring urged key 206. Slidable in the sleeve is a spring urged push rod 210 having a clevis 219 pinned thereto at 221, and slidably connected to the clevis is an arm 225 which carries a scraper blade 230. Arm 225 is releasably held in a bracket 232 on head 120 by a pin 231, so that on completion of the scaping operation, the scraper assemblies are removed from casings 202 to allow the boring operation to be carried out by bits 175, and the casings are plugged by plugs 240, Fig. 19. In operation clamps 84, Fig. 9, are retracted and cradle 35 is rotated by motor 50 to a vertical position, Fig. 5, and reactor 20 is lowered into the cradle by an overhead crane. Clamps 62, 63, are actuated and the cradle is moved through 90 degrees until the open end of the reactor engages clamps 82 in assembly 26 and dog 55 actuates switch 57 to stop motor 50. Clamps 84 are actuated, hopper 243 is moved axially until it engages the reactor and scrapers 230 are attached to tool 116. Motor 123 is energized to rapidly advance carriage 27, clutch 150 being engaged and clutches 135, 154, disengaged and when scrapers 230 have entered the reactor, motor 123 is deenergized and motor 122 is energized thus stopping the feed and rotating the tool. Motor 124 is energized with clutches 150, 154, engaged and carriage 27 is advanced at the required rate, with motor 123 being driven at a slow idling speed. After completion of the scraping operation, motors 124, 122, are disengaged, clutch 154 is disengaged and motor 123 is energized in its reverse direction so that the tool is withdrawn, whereupon the scrapers are removed and plugs 240 inserted. Carriage 27 is again rapidly advanced by motor 123, with clutch 150 engaged and clutches 135, 154, disengaged and when the tool engages the material to be removed motor 123 is de-energized, clutch 150 is disengaged, motor 122 is energized and clutch 135 is engaged, thus rotating the tool and feeding carriage 27 slowly. When the material is removed through hopper 243, motor 122 is de-energized, clutch 135 is disengaged, clutch 150 is engaged and motor 123 is reversed to rapidly withdraw the tool. Clamps 84 are unlocked and the reactor is tilted back to a vertical position and removed. In a modification, Fig. 24, bits 310 are adjusted by a screw 314 and are clamped by a screw 316 and scrapers 320, Figs. 29-31 comprise a drag arm 321, a socket 322 and a link 323. Socket 322 is secured to a piston rod 340 by a bayonet slot 355, and the scrapers are urged into engagement with the work when fluid is introduced into a cylinder 353.