Improvements in a packaging machine

摘要

724,559. Making, filling and closing bags. BARTELT, H. L. Feb. 26, 1953, No. 5433!53. Addition to 702,723. Class 94 (1). The machine described in the parent Specification is modified by the provision of two spaced filling stations 15 and 18, Figs. 1 and 2, to which the bags are moved in succession by the conveyer, a charge of material being fed into the lower portion of each bag at station 15, the bag sealed transversely at 17 above the charge at an intermediate station 16, a second charge fed into the upper portion of the bag at station 18, the mouth of the bag closed by a transverse seal 20 at station 19 and the upper and lower portions of the bag separated at station 21 by cutting along the centre line of the seal 17. The bags are made by feeding a folded web 11 of bag material intermittently between reciprocating heat-sealing jaws 36 which form seams 39 at intervals, each bag being severed from 'the web at station 13 after being received by grippers on an intermittently-operated endless chain conveyer as described in the parent Specification. The seams 39 terminate short of the free edges of the web to leave edge portions 47 which are held apart by a V-section bar 40 and subsequently by similar bars 48 and 69 arranged adjacent the conveyer. The grippers 49 are arranged in pairs so as to engage the upper and lower portions of the bags, each pair comprising flanges on a plate 54, Fig. 8, secured to the conveyer chain 51 and cooperating U-shaped springs 56 secured to the plate. A bar 57, located by pins 58 on the plate and provided with an operating arm 59 forms a lever for opening the grippers. A tappet 63 located adjacent station 13 is operated by a cam 60 on a main cam shaft 27 to actuate the arm so that the leading end of the web is fed between the open jaws of the grippers and then gripped prior to the severing of each bag. Filling spouts 68 and 70, Fig. 9, at stations 15 and 18, are mounted on members 75, 751 pivoted to parallel arms 79 and 80 which are pivoted at 81 and 82 to a fixed plate 83 and are swung upwardly and downwardly by linkage 87 operated by a cam 86 on the shaft 27, each spout comprising two tapered members 71 and 711, Fig. 10, of channel cross-section mounted on parallel shafts 72, 73 or 721, 731. The shafts are coupled for simultaneous rotation in opposite directions by a lever 92 or 921 connected by a spring toggle 98 or 981 to the member 75 or 751, a pin 105 or 1051 on the lever engaging a stop 102 or 1021 on the plate 83 as the spouts move upwardly to move the linkage through the dead centre position so that the members 71 or 711 are held closed for the reception of a measured charge from a hopper 90 or 901. As the spouts are moved downwardly into the bags, the pin engages a second stop 103 or 1031 and the linkage is again moved through the dead centre position so that the spring 102a operates to open the members 71 or 711 with a snap action, thereby spreading the bags and releasing the charges of material. In the lowered position of the arms, the spout 68 extends into the lower portion of the bag at station 15, whereas the spout 70 only extends into the mouth of the bag at station 18. The seal 17 is formed at station 16 by heated jaws 107, Fig. 15 carried by levers 108 operated by cams 110 on the shaft 27, similar mechanism being provided at station 19 for forming the seal 20. The upper and lower portions of the bag are separated by reciprocating knives at station 21 operated through linkage by a cam 123 on the shaft 27, and the two filled bags thus formed pass through an opening 124 into a delivery chute 25 and are released by the engagement of the arm 59, Fig. 8, with a roller 125.