Patent GB-650162-A (GB)
Title: Machine tying of hams and the like
IPC: A22C11/00
Filed: 1948-01-06
Abstract: 650,162. Tying packages. BUNN CO., B. H. Jan. 6, 1948, No. 436. Convention date, Dec. 5, 1941. [Class 94(i),] A method of tying a package comprises locating one end of the package in a tying plane at a position remote from a twine anchorage point contiguous to the plane, tying the twine around this end, rotating the package by a right angle in a direction to cross the ends of the twine and to locate the length of the package in the tying plane with its other end adjacent the anchorage, tying the twine around the package lengthwise thereof and rotating it through a further right angle to cross the ends of the longitudinal tie and locate the second end in the tying plane and adjacent the point of anchorage, tying the twine around the second end and securing the free end of the last tie to the anchored end of the twine. As applied to a machine for tying hams, a main frame 11 is rigid with a table 36a which is separated by a gap 36b, Fig. 4, from a table 36. The latter is supported by arms 34, 35 secured to a member 33 journalled on a hub a carried by the frame 11. Movement of the table about the hub is prevented by means of an anchoring member 40, Fig. 8, journalled on the frame 11, which has wing-portions 43, 44 engageable with a channel formed in a member 38 rigid with the table 36. Twine is fed by an L-shaped twine arm 24 which is rotatable about the axis of the hub a so that its extremity, from which a reach 60 of twine passes to a twine catcher 86, Fig. 2, moves in a plane containing the gap 36b. The twine catcher and mechanism for subsequently knotting the tie comprising a knotting beak 80, may be as described in U.S.A. Specification 1,606,290 and Specification 449,019. The mechanism for rotating the twine arm at the desired intervals of the complete wrapping cycle of the machine comprises a mutilated gear 20 and driving pinion 23 and is as described in the above-mentioned Specifications. The mutilated gear 20 has a second unmutilated series of teeth which engage a pinion on a drive-shaft 19. The mutilated teeth of the gear 20 engage the pinion 23 which, however, is held against rotation while in engagement with the mutilated portions of the profile. This condition obtains at the end of each complete rotation of the twine arm 24 which is brought to rest at the correct point by a brake comprising a sheet metal bracket 29 over which is stretched a strap 27 of leather which the twine arm frictionally engages. The pinion 23 is in driving engagement with the arm 24. The twine arm makes three complete revolutions for each revolution of the mutilated gear 20. A shaft b rotatable by the mutilated gear 20 carries a cam block 25 having three projections 68, 69, 70, Fig. 2, which are engageable with an arm 71, Figs. 1, 3, to displace the actuating arm 78 of a clutch (not shown) so as to discontinue the drive to the shaft 19 from a main driving motor 16. The clutch arm 78 is set in the driving position at the commencement of the tying cycle by the depression of a foot treadle 76 which is connected to the arm 71 through linkage 75, 72. The wing-portions. 43, 44 are dimensioned so that on partial rotation of the member 40 to withdraw either wing-portion from the channel, both are in engagement with the channel at the instant of withdrawal. The member 40 is oscillated against the action of a spring 67 by the action of a pivoted lever 45 the other end of which engages a cam 59 on the main cam block 25. The profile of the cam 59 has three raised portions, Fig. 7, (not shown), engagement of which, with the arm 45 correspond to the full-line position of the member 40 in Fig. 8, the position otherwise being as shown dotted. The member 40 is in the full-line position prior to commencement of the tying cycle and the reach 60 of twine extends between it and the member 38. When the twine arm commences its rotation the member 40' is oscillated by the link 45 and thus allows the twine to pass upwards through the slot 36b as it is drawn around the article by the twine arm. Operation.-In tying up a ham 79 in the manner shown in Fig. 9, the ham is placed on the island table 36, with the shank end around which a first loop x is to be formed, lying over the gap 36b. The treadle 76 is depressed so as to initiate rotation of the shaft 19 and thereby the rotation of the twine arm 24. The twine passes up above the member 40 as described and is drawn around the shank end and comes to rest when the projection 68 initiates release of the clutch 78a, (not shown). The ham is then turned horizontally, clockwise (as viewed in Fig. 4) by the operator, about a central vertical axis in the plane of the loop x until the longitudinal axis of the ham lies parallel and above the gap 36b. The treadle is depressed and a longitudinal loop y is formed. The ham is then turned again clockwise, this time about a central vertical axis through the transverse plane of the ham in which the final loop z is to lie. The tie is then knotted by means described in the above-mentioned Specification and U.S.A. Specification. The larger angle between the projections 69, 70 on the cam block 25 (as compared with that between 68, 69 and 68, 70) allows for this mechanism to be actuated from the shaft 18. after the third complete rotation of the arm 24. It is necessary for the ham to be positioned in Fig. 4 with the shank end at a correct distance from the knotting beak 80 so that the final loop z will be formed slightly to the left of the knotter beak. If an article is to be tied with two loops instead of three, the treadle 76 is pressed to produce the first rotation of the twine arm before placing the article on the table 36. Similarly a single loop only may be tied by operating the treadle a second time following the first idle rotation.