| 摘要 |
499,938. Endless-belt conveyers. GRRER CO., J. W. June 14, 1938, No. 17641. Convention date, June 24, 1937. [Class 78 (i)] In means for spacing article's on convever belts two complementary moving conveyer sections separated by a transfer gap are provided in combination with means for varying inversely the relative lengths of the sections to increase the length of first one and then the other at a substantially uniform rate. Variable speed driving means is provided for driving each section at one rate while it is being increased in length and at a faster rate while it is being reduced in length, these rates being adjusted with relation to the rate of variation in length to prevent articles from crossing the transfer gap during the movement of the gap in the direction of feed, whereby a space is opened up between the articles grouped on opposite sides of the gap. The belt 12, Fig. 1, on which the articles are spaced passes over a knife edge 14 adjacent to a feeding conveyer 40, around a knife edge 18, take-up roller 16, and knife edge 20 forming a part of the compensating take-up, over an idler roller 22 adjacent to a delivery conveyer 44, around a driving drum 24 and idler roller 28 to a roller 32, take-up roll 30 and roller 34 forming another part of the compensating take-up, thence around an idler roller 36 to a driving drum 26 and back to the knife edge 14. The compensating take-up comprises two uprights 100 which are connected at their upper and lower ends by cross-members, and are formed with sleeves 108, 110, Fig. 4, which are in driving engagement with spiral cam shafts 112, 114. These shafts are connected by chain-and-sprocket gearing, and the shaft 114 is driven by a shaft 58 through similar gearing of such ratio that the take-up is reciprocated in the line of feed at substantially the same rate as the belt 12 is advanced. The driving drum 24 for the belt carries pawls 84 which are engaged by a ratchet wheel 82 fast on a shaft 66, Fig. 5. A shaft 64 in alignment with the shaft 66 is in driving connection with it through a spur gear 68, three planet gears 70, and three gears 76 which engage with a ring gear 78 secured to a housing 80 fast on the shaft 66. The shaft 64 is driven from a main drive shaft 48 through a clutch 50, shaft 52, gears 54, 56, shaft 58 and bevel gears 60, 62. A sprocket 74 fast on the shaft 66 carries the shafts 72 of the gears 70, 76 and is connected by a chain 90 to a sprocket 92 loose on the shaft 94 of the drum 26, Pawls 96 on the sprocket 92 engage a ratchet wheel 98 fast on the drum shaft. The take-up rollers 16, 30 are mounted in slidable members 140, 142, arranged in vertical guides formed in the uprights 100. The slides are moved up and down by the action of sloping rails 148 on blocks 144, 146. |
