| 摘要 |
943,526. Engraving. GRAPHIC ELECTRONICS Inc. March 5, 1962 [Dec. 29, 1961], No. 8452/62. Heading B6J. [Also in Division B3] An engraving machine of the type comprising a scanning cylinder on which a photograph or other copy is mounted, an engraving cylinder on which a metal or plastic plate to be engraved is mounted, an engraving tool and scanning apparatus for sensing the light reflected from the copy and transmitting electrical impulses proportional thereto to the engraving tool, has a lead screw for simultaneously moving the engraving tool and the scanning apparatus along their respective cylinders, thrust bearing means preventing axial movement of the lead screw when the latter is rotated during an engraving operation. The thrust bearing is mounted in a housing 56 carried by the machine frame. One end of the lead screw 38 is secured to a shaft 92 journalled by means of a leather gasket 98 in a bore 60 in the housing 56. A reduced-diameter threaded portion 94 of the shaft 92 is received in a threaded hole 90 in one end of a shaft 47 which is journalled by means of a leather gasket 80 in an end-plate 84 of the housing 56. A reduced-diameter portion 62 of the shaft 47 has frictionally mounted thereon two inner races 70, 74 of roller bearings 66, 68. Cages 71, 76 carry inclined sets of rollers 72, 77 respectively which are interposed between the races 70, 74 and outer races 73, 78, the outer races being positioned in a bore 58 in the housing 56. The shaft 47 has a ratchet wheel 48 fixed thereon and is intermittently rotated by means of a pawl which coacts with the ratchet wheel. Such rotation is transmitted through the shaft 92 to the lead screw 38, the roller bearings 66, 68 constituting thrust bearing means which prevent axial movement of the connected members 47, 92, 38. |
