Patent GB-676036-A (GB)
Title: Improvements relating to the mechanical dressing of fish
IPC: A22C25/14
Filed: 1950-01-18
Abstract: 676,036. Beheading fish. FISADCO, Ltd. (Baader, R.). Dec. 29, 1950 [Jan. 18, 1950], No. 1352/50. Class 28 (ii). A fish 53, Fig. 6, carried round on a rotating drum 10 or otherwise conveyed, is transversely cut or beheaded by a rotating disc knife 16 which is automatically swung into contact and travels along with the fish during cutting. The fish is drawn around by its tail, being gripped by a cam-operated tail clamp 12 as its back fits into a groove 14 in the rotated drum 10. The swing-in of the knife is effected by partially rotating the offset knife holder 18 in its boss 44 through a gear 50, Fig. 2, rotated by a sector gear 48 on a lever 46 rocked by a cam 51 in a rotated cam track 52. The detail of the knife and its mounting are as in Fig. 7 (not shown) the rotation being through reduction gear and a worm drive. The knife movement actually makes a curved cut 57 following close behind the curve of the gills. The knife can be adjusted to compensate for wear after grinding through bolts 49 in slots. A knife guard 45 accompanies the knife movement and carries a platform 47 to support the fish body during beheading. To provide an accurately positioned cut off, for varying lengths of fish a feeler 20 bears on the fish body and when it drops over the bony ridge at the eye on to the narrower snout it starts the swinging-in of the knife as follows. The drop of 20 causes a bolt 28 on a bellcrank 22, 26 to rock another bellcrank 30 to release a latch 32 from 34 whereby a lever 36 is rocked by a spring 38 to lower a pawl 40 into engagement with a continuously rotated toothed ring 42, the pawl being coupled to the cam track 52 operating the swing-in of the knife. Before the next fish comes round, the feeler 20 is partially raised by a cam on the drum face, to allow the tail to slip underneath 20 which then follows the body contour as above. The feeler shoe 20 should initiate the cutting mechanism just behind the gills when it drops over the bony ridge at the eyes. To compensate for the small extra distance from the eyes to the gills in a longer fish, the shoe is automatically drawn to the right in Fig. 2 to shorten the time of the drop and so actuate the cutter earlier. This is done by a continuously rotating cam 80 which depresses roller 78 so as to swing 26, about its upper shaft or pivot, to the right thereby carrying its other arm 22 and attached feeler 20 to the right. The cam 80 is on the same shaft as the cam 70 which initiates the movement of the cutting mechanism in accordance with the length of the fish so that the initiation of the cutting is accelerated by the cam 80, the amount of such adjustment being greater in the case of a longer fish, since the cam 80 will have rotated more in the time that the fish length would take to move under the feeler from tail to the bony step or ridge at the eye. After the knife 16 has been swung-in and out again by the rotation of the cam track 52 the mechanism is re-set for the next fish. A cam 86 on the toothed ring 42 lifts roller 82 and pawl 84 out of engagement with the teeth of ring 42, so disconnecting the drive to 52 for the knife movement. This disconnection starts just before the complete swing back of the knife but an automatic spring clutch (88, Fig. 4, not shown) in the drive applies sufficient torque to return the cam track 52 to exactly the same position