| 摘要 |
1,251,627. Closing packaging containers. DAREF GESELLSCHAFT FUR KUNST. STOFF - VERARBEITUNGS MASCHINEN m.b.H. 6 May, 1970 [13 May, 1969], No. 21715/70. Heading B8C. A machine for closing a packaging container 1 with a thermoplastic lid 2 comprises a stationary lid carrier 5, a displaceable heater 28, and upper and lower tools 3, 6 movable axially relative to each other against a spring 14 by means of control cams 8, 9 and 10, 11 respectively, the lower tool 6 accommodating a container carrier 7 which is movable vertically therein by means of a control cam 12, 13 and the upper tool 3 providing a housing for two roll membranes 15, 16. The latter form a closed container 18 which is filled with incompressible liquid 18 and which is divided by an intermediate plate 22 having fluid transfer openings 24. The volume of fluid within the membrane 16 can be varied by an upper disc 21 which is movable axially against a spring 20, the lower membrane 15 being supported by a pair of plates 19a, 19b which are carried by a rod slidable in a bush 23 in the plate 22 and which define a peripheral rollable extension. A package 1 to be closed is placed in the carrier 7 and the lid 2 is placed on the carrier 5 where it is retained by the upper tool 3 while it is softened by the heater 28. The latter is retracted and the lower tool 6 is moved upward until a seal 26 thereon contacts the carrier 5 to form a closed cavity 27 within the tool housing 6. The container carrier 7 is then raised to make contact with the disc 19a and lower the pressure in the cavity 27. Simultaneously the disc 21 is lowered so that the rollable extension of the membrane 15 wraps itself around the mouth of the container 1 and presses the lid 2 thereon, the vacuum in the cavity 27 assisting by pulling downwardly on the lid. The upper side of the lid 2 remains under atmospheric pressure by virtue of a duct 25. In the next stage the upper tool 6 is raised to release the lid 2, the carrier 7 following the upward movement so that the edge of the lid is wrapped completely around the mouth of the container 1 whereupon the components of the machine are returned to their original positions. |
