| 摘要 |
1,025,149. Jacks for erecting silos. A. O. SMITH HARVESTORE PRODUCTS Inc. Oct. 21, 1963 [Oct. 31, 1962], No. 41537/63. Heading B8J. [Also in Division E1] In the erection of a silo, to provide for circumferentially off-setting the vertical joints between the plates 5 of cylindrical sections 4 which form the shell 1 of the silo, lifting heads 43 of a ring of jack assemblies 12 are moved circumferentially as well as upwardly. Initially, the lowermost section 4 and jack columns 23 are secured to the foundation 2. After securing telescopic braces 29, 32 to the jack columns, lifting plates 62, Fig. 8 (not shown), of the lifting heads 43 are set at the same height with respect to the foundation section 4, and driveshaft assemblies 94 are installed between the jack operating shafts 91, Figs. 2, 6 (not shown). A drive motor 110 is air actuated but an hydraulic or electric motor may be used. Roof-supporting centre posts 36, 37 are next assembled and let-down blocks 120 are positioned adjacent the upper edge of the foundation section 4. Locating pins 80 are then inserted into the lifting plates 62 which are lowered to the proper level for installing the first or uppermost cylindrical section 4. The sheets 5 of this section are placed on the locating pins 80 and thereafter lifting pins 73, which also pass through vertically aligned slots 74 formed in the lifting plates, are inserted through aligned bolt holes in the vertical edges of the sheets 5. After the first cylindrical section has been assembled it is raised to the proper height for building the roof which comprises panels 10 connected to the roof cap 11. The structure so far completed is then elevated by operation of the motor 110 to a height sufficient to permit a second section 4 to be attached to the lower edge of the first section. After attachment of the second section to the first section, wedges 123 are positioned on the let-down blocks 120 and the structure is lowered on to the blocks. The lifting pins 73 are then removed from the bolt holes in the sheets 5 and the braces 29, 32 are disconnected so that the jack columns 23 can be pivoted toward the centre of the silo. The lifting heads 43 and lifting plates 62 can then be lowered such that the vertical slots 74 in the plates 62 are aligned with the bolt holes in vertical edges of the second cylindrical section 4. The lifting pins 73 are then inserted through the bolt holes and slots 74 and the entire structure is elevated to a position where a third cylindrical section can be attached to the lower edge of the second section. This procedure is repeated until the entire silo has been assembled. Circumferential and lifting action of jacks.- Each jack includes a vertical U-section column 23 having a cam track 81 which is engaged by a cam follower 82, Fig. 8, (not shown). A support member 83 for the follower is welded to the lifting plate 62. When the jack is operated the lifting plate 62 and the assembled portion of the silo will be lifted but will also rotate a small amount as the cam follower 82 moves upwardly in track 81. Other features of jack.-A nut housing 55 contains a ball-bearing type nut which engages a screw 51 and the housing is secured to the lifting head 43. The head is mounted for movement on the jack column 23 by a lower roller 46 and an upper roller 47, the latter being provided with outwardly extending shoulders which maintain alignment of the roller with respect to the edges of the jack column. The lifting plate 62 is supported for lateral movement on a curved front plate 44 of the lifting head 43 by a pair of rollers 64 which ride along the upper edge of the plate 44. In addition, a pair of rollers 65 ride on the rear surface of the plate 44. A pair of horizontal rollers 67 ride within curved recesses 69 formed adjacent the lower edge of the lifting plate 62. Screw 51 is driven by a worm 90 and worm gear 89 onctained in a gear-box 26, Figs. 5, 6 (not shown). A shaft 91 which carries the worm has spline adaptors 95 for engagement with sockets 96 of universal joint yoke members 97, Fig. 3 (not shown). These members are provided at each end of the drive shaft assemblies 94. A base plate 13 has a foot 14, and pins 15 locate the plate by engagement in openings in a base angle 8 secured to on the concrete foundation. The pins 15 are screwed to permit adjustment for levelling the plate 13 which is held down by a pair of brackets 17. |
