GB1236251A - Improvements in or relating to packaging machines - Google Patents

Abstract

1,236,251. Filling bags. CARRINGTON & DEWHURST ENG. Ltd. 14 Aug., 1969 [15 May, 1968], No. 23042/68. Heading B8C. A machine for filling bags with articles, e.g. a sliced loaf or a group of cakes &c., comprises an in-feed station 1, an assembly station 2, article-transfer paddles 9, a filling station 3 and a bag-closing and discharging station 4. The infeed station 1 comprises a stepwisely movable endless chain conveyer 5 divided by adjustable flights 6 into pockets 7 which transfer the articles to the assembly station 2. The paddles 9 and a pressure plate 11 a attached to the piston of a cylinder all supported from a rod 10, Fig. 3, are moved in closed paths, as shown, by a crank 12, linkage 13-19 and a cam-wheel 20, so that the paddles 9 are clear of the articles during their return, idle stroke. During the forward stroke of the paddles, the articles are gripped between the paddles by inward movement of one (or both) of the paddles by a cylinder (22), (Fig. 4, not shown) and the articles are discharged on to a reciprocable front-part 8b of a two-part receiver 8, via its rear, stationary part 8a. Simultaneously, the uppermost bag of a stack is opened by a mechanism shown in Figs. (5), 6. Each bag of the stack has its lower wall longer than the upper one and the edge portions of the lower walls of all the bags are held on a platform 26a by a #-shaped wicket 25, Fig. 3, which passes through spaced holes in the lower walls. The bags are gussetted at the ends forming the bag bottoms and the central body of the stack is held on a vertically movable platform 26, the gussetted ends lying on a front platform. The platforms 26a, 26 and the front platform, on which the stack thickness is in the ratio of 1: 2: 4 are so coupled together that their vertical movement is always in this ratio, i.e. 1: 2: 4 so that the uppermost bag can always be kept at a constant level. The bag-opening mechanism has two air blowers 28 directed towards the bag mouth and two pairs of fingers 27 at the bag sides. During the forward stroke of the paddles 9, the air blowers partially open the top-bag mouth, the fingers 27 move into the bag and the upper fingers move outwards and upwards to fully open the bag as shown in Fig. 6. The receiver part 8b then withdraws, the articles being held in the bag by the plate 11a which further pushes them into the bag and then severs the filled bag from the wicket 25 along lines of weakening between the holes and the edge of the lower wall of the bag. The filled bag is then passed directly or via an outfeed conveyer similar to the infeed conveyer 5, to a bag-closing mechanism which necks the bag and winds a clip thereabout, straight seals the bag, or twist-ties it. The receiver part 8b may be driven by a cam mechanism. The vertical movement of the platform 26 is effected by an actuator which may be a lever/wedge mechanism, a cam/lever/clutch mechanism or a fluid pressure operated mechanism. The movement of the fingers may be cam controlled. The blowers 28 are time-controlled by camoperated valves. The machine may be modified in one or more of the following ways: (a) the rear receiver-part 8a may be replaced by a spring-loaded belt passing over guide rollers and attached to the front part 11(b) ; (b) the parts 10-20 may be replaced by a slide rod between the assembly and filling stations 2, 3, the slide rod mounting a carriage which carries spaced paddles 9 cam controlled in such a way that during their idle stroke, they pivot upwards to remain clear of the articles at the station 2. (c) The bag-stacking platform 26 &c. may be replaced by a bag-making device which employs an off-centre folded, continuous web.