Patent GB-553447-A (GB)
Title: Improvements in or relating to decorticating machines
IPC: D01B1/10
Filed: 1942-01-12
Abstract: 553,447. Decorticating sisal &c. SIMONS, W. B. Jan. 12, 1942, No. 459. Convention date, Jan. 6, 1941. [Class 120 (i)] In a decorticating machine comprising a scutching drum 12, Fig. 2, co-operating with a breast plate 17 the blades 25 on the drum are mounted so that at the leading edge of the plate certain of the blades form an acute angle and act primarily to crush the non-fibrous material of the plant parts, Fig. 3, while other blades form an obtuse angle with the plate, Fig. 4, and serve to scrape the non-fibrous material from the fibres. The blades are mounted in pairs the leading blade forming an angle of about 75 degrees at the leading edge of the plate and the trailing blade an angle of about 105 degrees. The machine comprises the roll or drum 12, cover sections 16, 16a, Fig. 1, and a pair of rasping plates 17, 18 offset laterally. The body of the scutching roll is hexagonal and the blades 25 are formed by the flanges of channel members 24. Leaves or other plant parts to be treated are arranged lengthwise on tables 26, 28 and fed through openings 27, 29, freely-mounted rollers 30 being provided to prevent the escape of plant juices liberated in the operation. Alternatively a curtain formed of strips of rubber or other material may be substituted for the rollers 30. In operation the material is held by the point end and fed butt end foremost into the machine and then withdrawn. The material is then held by the treated butt end and the point treated to complete decortication. The openings 27, 29, are offset laterally so that plant parts inserted from opposite sides of the machine will not become entangled. If desired however the openings may extend the full length of the roll 12. The butt ends may be treated at one side of the machine and the point ends at the other the clearances between the roll 12 and the respective breast plates 17, 18 being appropriately set. The bearing blocks for the roll 12 are adjustable in the machine base and screws 37 are provided for use in adjusting the parts. In a modification the bearing blocks for the roll and the breast plate are adjustably mounted upon supports inclined at an angle of approximately 30 degrees to the horizontal. The plant parts may be fed into the machine mechanically by grippers 51, Fig. 7, provided at intervals on a chain 47. The grippers 51 comprise jaws 52, 53 normally closed by a spring but which may be held open for insertion of the material by a cam rail 58 engaging the tail-pieces of the jaws. The leaf 46 is advanced into the machine 42 and withdrawn therefrom as the gripper passes round the sprocket 50 the treated leaf passing down an inclined support 59 and between two bladed members 60, 61 which subject the fibres to a light beating action. The members 60, 61 are mounted on arms 74, 75 pivoted at 67 and, at intervals, the arms are separated by the action of a cam 78 to permit the passage of the grippers 51 which then pass into engagement with the rail 58 and deposit the fibres on a conveyor 84. After the butt end has been treated the fibres are preferably twisted into a compact stem before being gripped by the members 51. This may be effected manually or by means of a.rotating tubular element 85 formed with a flaring entrance which tapers to a bore having diametrically opposed channels.