GB630363A - Sheet feeding mechanism - Google Patents

Abstract

630,363. Feeding sheets. ADDRESSO- ' GRAPH - MULTIGRAPH CORPORATION. July 14, 1947, No. 17600/49. Convention date, Feb. 8, 1941. Divided out of 630,336. [Class 100 (i)] A sheet separating and feeding mechanism for feeding sheets to an offset printing machine comprising cylinders 26, 27, 28 driven by a motor 30 as described in Specification 630,336 from which the present application is divided, is constructed with means for separating the sheets from the pile W in the form of a suction foot 60 carried by a shaft 66 pivotally mounted in arms 63 on a shaft 68 which is oscillated by a crank 21 driven by the printing-machine and link mechanism. As the foot 60 is raised from the top of the pile, a roller 76 mounted in the carrier 75 of the foot engages a guide 77 under action of a spring 78, and the foot is moved slightly rearwards and assumes the positions indicated at 79, Fig. 5, and then a roller 80 mounted in the carrier 75 engages an adjustable screw 81 and the separator with sheet attached is swung forwards to carry the sheet into the bite of rollers 61, 62. Double feed is prevented by adjustable scrapers 86 acting on the front edges of the sheets. The pump 90, which is connected by exhaust pipes to the separator, is connected by a pressure pipe to a blast pipe 110 which assists in the sheet separation. The suction to the foot 60 is cut off automatically by the opening of a valve 99, Fig. 4, by means of a screw 103 on a lever arm 101 on the shaft 68. The valve is held open by a catch 108 on a lever 106, which is automatically operated to release the catch on return of the arm 101. In a modification wherein printing is effected for each two revolutions of the press, means are provided for allowing the valve 99 to be kept open long enough to permit of the feeding of only one sheet for each two revolutions of the press.