GB1268981A - Seed tape manufacture - Google Patents

Abstract

1,268,981. Packaging seeds. UNION CARBIDE CORP. 13 Feb., 1970, No. 7000/70. Heading B8C. In the manufacture of seed tape, seed pick-up nozzles 75 mounted on an assembly 35 are rotated in an inclined plane to pick up seeds from a rotating annular seed tray 40 and to release the seeds above a continuously moving tape 20. The nozzles and the tray rotate in the same direction to avoid disturbance of the seed bed 24 at pick up, and the tape and nozzles move in the same direction at the release point 23 to promote accurate placing of the seeds on the tape. As each nozzle 75 moves through the bed 24, a passage 72 communicating with the nozzle moves into registry with an evacuated arcuate groove, Fig. 5 (not shown), formed on the lower face of a stationary plate 50 so that seed is picked up by the nozzle and lifted out of the bed. Each nozzle has a number of openings corresponding to the number of seeds to be picked up. After moving out of registry with the groove, the passage 72 communicates through a passage 60 with atmosphere, or with a source of pressure slightly above atmosphere, so that the seeds are released when they are above the tape 20. Thereafter, the passage 72 is brought into communication, through a further passage in the plate 50, with a source of compressed air to clear the nozzle. The seed bed is protected from the resultant air jets by a plate 71 (Fig. 1). While rising from the bed 24, the nozzles are cleared of any excess seeds by a compressed air nozzle 96. The surface of the seed bed is maintained level by a freely pivoted plate 104 which also acts through a micro-switch 106 to control the supply of seed to the bed from a reservoir 100 through a vibratory trough 101. A tape drive and sealing roller 21, the tray 40, and the nozzle assembly 35 are driven by the same motor 27 to ensure synchronization of their movement. A variable speed transmission 32 allows the seed spacing on the tape to be varied by adjustment of the speed of the nozzles relative to the tape, and a further variable speed transmission 38 allows adjustment of the speed of the nozzles relative to the seed bed. The tape is made of watersoluble polyethylene oxide and, prior to movement through a trough-shaped former 86, is slightly moistened by a spray 90. The spray moistens less than half the width of the tape so that seed deposited in the centre of the tape remains dry.