| 摘要 |
963,243. Tube extractors. CALIFORNIA RESEARCH CORPORATION. Oct. 2, 1962 [Oct. 2, 1961], No. 37427/62. Heading B4C. [Also in Division B8] A bundle of tubes 66, Fig. 1, for a heat exchanger is supported, whilst being inserted or withdrawn, by a beam 50 on which run trolleys 58, 60, 68. The weight of the tubes is supported by band slings 62, 64 and the tubes are moved by an air motor 196 through a bar 228. Whilst the pipe bundle is being moved the beam 50 is clamped to the shell 48 of the bundle by arms 70, 72, Fig. 3, which have parallel linkage rods 96 and are opened and closed by a hand wheel 124 and a screw and nut device 104, 106, 110, 112, 116. These arms are clamped to plates 132, 134, or 144, 146, which are bolted to the shell, by bolts 92 and cross-pieces 160, Fig. 4. In a first embodiment the air motor 196, Fig. 7, moves the rod 228 and with it the bundle of tubes, by concentric screws 206, 216, interconnected by recirculating balls 212. When the screw pulls or pushes on the tubes the carriage 68, Fig. 5, tilts, and bearing pads 178, 180, 182, 184 jam it in position on the beam. Formulµ are given for calculating the dimensions of the carriage to ensure this jamming. On reaching the end of its travel, limit switches 324, Fig. 7, or 326, are operated by members 314, 322 to reverse the direction of the air motor to turn the screw in the opposite direction. These limit switches also cause a wheel 240, Fig. 5, to be depressed by a pneumatic cylinder 244, thereby raising the carriage 68 until wheels 246, 250 abut the underside of the beam 50. In this condition the carriage is moved along the beam by the screw instead of jamming so that it becomes suitably positioned for another pull or push on the tubes. The pneumatic control circuit is diagrammatically illustrated in Fig. 15 (not shown). In a second embodiment the tubes are pulled or pushed by a bar 532, Fig. 18, pivoted to a carriage 502 which is moved along a beam 500 on wheels 522 by a screw 506 and a nut 538, driven by a reversible air motor 504. The screw is long enough to allow the tubes to be pulled completely out in one movement and is centrally supported by a spring-loaded arm 540, Fig. 23, which is cammed aside as the nut 538 approaches. The effective length of the sling 64, Fig. 16, is adjusted by a hand wheel 456 and a screw 448 mounted on the carriage 60. The carriage is raised and lowered with respect to the beam 50 by an hydraulic piston device 390, 396 controlled by a release handle 419 and a manual pump 418. An eye 474 on one end of the sling is releasably pinned to the carriage 60 by a pin 476 with a handle 488. |
