Patent GB-648684-A (GB)
Title: Improvements in or relating to method of closing filled bags
IPC: B65B7/08
Filed: 1947-07-15
Abstract: 648,684. Closing filled bags. CONSOLIDATED PACKAGING MACHINERY CORPORATION. July 15, 1947, No. 18790. Convention date, May 22, 1940. [Class 94(i)] A method of closing a filled bag comprises the steps of folding and sharply creasing a marginal portion of the collapsed upwardly extending mouth portion along a line parallel with and close to the upper edges thereof to provide a narrow return fold portion, folding the mouth portion along a line parallel to the plane of the top of the contents and in a direction opposite to that of the return fold portion so as to bring the line of fold of the return portion adjacent the intersection of the shoulder of the bag and the upwardly extending mouth portion, restraining the return fold against unfolding, then folding the entire upstanding portion along said line of intersection and pressing the mouth portion against the top of the bag while releasing the end containing the return fold from restraint. Creasing bag mouth and forming upper fold.-The collapsed upstanding mouth portion of the bag is disposed between a creasing blade 10 and crease anvil 13 on one side and a creasing block 16 on the other. A thin tongue 17 on the block engages with a groove 14 in the anvil 13 when the block 16 is moved into operative position by cam .and follower mechanism and forms the lower crease in the bag mouth. The upper fold is formed by a V-shaped edge 11 on blade 10 which engages between a bevelled surface 19 on block 16 and a bevel-edged hinged plate 20 which is pressed upwardly by a spring 22. A roller 26 carried by an arm 28 rotated by further cam and follower mechanism depresses plate 20 and forms a sharply creased return fold portion 27 (see Fig. 3). Forming lower fold.-The bag mouth is folded over along the lower crease line by the forward and downward movement of a folding member 212 having spaced extensions 211 fixed to the upper ends of a yoke 213 pivoted at 209 to an extension of a plate 207 slidably mounted below the blade 10. The folding member is normally maintained in contact with the lower surface of the blade by means of a spring 214. After the creasing block 16 has been withdrawn to the position shown in Fig. 1 a link 216 actuated by cam and follower mechanism slides plate 207 forwards and causes the yoke 213 to strike against adjustable lock nuts 217 on a fixed bolt 215 thereby rocking the yoke and causing the folding member to drop forward to the position shown. Glueing, final folding and pressing.- ((Fig. 7). The bag is moved by feed means (not shown) to a position where glue is .applied to the shoulder of the bag by a glue blade 310, and a tucker blade 320 engages the end portion of the return fold 27 and tucks it tightly into the crease formed when a member 265 folds and presses the folded mouth portion against the adhesive coated shoulder to form a tight seal. The tucking blade 320 is carried by resilient fingers and is depressed by fins 291 on member 265 to ensure a tight fold when the member is moved by cam and follower mechanism (not shown) first forwardly and then downwardly, Fig. 8, (not shown). The member 265 is provided with a channelshaped upper end 290 which has. a flared mouth at one end to ensure guidance of the previously folded bag mouth into the channel as the bag is moved laterally into position. The folding and pressing movement of member 265 resembles the action of a person's hand. Trimming.-Fig. 9 (not shown) illustrates a modification of the crease forming mechariism when the bag ends have to be trimmed. Thus the blade 10 is replaced by a movable male creasing member the upper edge of which comprises a movable shear edge which co-operates with a stationary shear blade rigidly secured to the frame. The block 16 is provided with a female creasing member carried by arm 231 and adapted to register with the male creasing member. Specification 648,685 is referred to.