GB670078A - Packaging articles - Google Patents

Abstract

670,078. Wrapping machines. WING- FOOT CORPORATION, Sept. 7,1948 [April 3, 1948], No. 23503/48. Class 94(i) [Also in Group V] A process for packaging an article such as an orange, between two stretched, heatsealable and heat-shrinkable films, comprises covering with the stretched films opposite surfaces of the article, pressing the films tightly together around the peripery of the article and then applying heat and pressure to the films in the areas surrounding the portions which are pressed together to unite them. The pressure is subsequently relieved to allow the films to shrink into close contact with the article. In the apparatus shown, stretched rubber hydrochloride films 19 and 24 are fed over the peripheries of hexagonal drums 1 and 2, which are rotated intermittently in opposite directions to bring the faces A-F of the lower drum opposite the faces A<SP>1</SP>-F<SP>1</SP> of the upper drum in succession. The upper drum is mounted for vertical movement under the action of air cylinder 10 whereby opposed faces may be pressed together and then separated. Each face of the drum 1 is provided with a depression formed by a cup 30 resiliently mcunted by means of a spring 31, and each face of the drum 2 incorporates a similar cup 32. Each cup is connected by a pipe 34, port 36 and the hollow axle 35 of the drum to a source of vacuum, the ports being closed and opened in rotation by a stationary plate 37. Each cup 30 is slidable within a ring 63 of asbestos which is surrounded by a ring 62 of low heat-conductivity in contact with an electrically-heated metal ring 61. The corners of the drums are provided with rubber members 82, 83 which grip and prevent movement of the films. Assuming the drums are initially in the position shown in Fig. 1, hot air is supplied through a pipe 22 to heat the film 19 on face A and vacuum is simultaneously applied to the cup in that face to suck 'the heated film into the cup. The drums then rotate to the next station where hot air is supplied through a pipe 26 and the heated film 24 sucked into the cup in the face B<SP>1</SP>. At station C, an orange 41 is dropped into the film-lined cup, and at station B the opposed faces D and D' of the two drums are pressed together by operation of the air cylinders 10, thereby clamping the films between the rims of the cups 30D and 32D. At the same time, the cup 30D is moved downwardly against the action of its supporting spring so that the rings 62 and 61 are pressed against the lower film. The ring 62, which is at a lower temperature than the ring 61, seals the films together, and the ring 61 severs the films around the periphery of the heatsealed portions. The drums are then moved apart to allow the heated films to shrink into close contact with the orange, and the completed package is delivered from the lower drum at station E. In modifications, Figs. 9 and 10 (not shown), the heated ring is raised above the surface of the heatsealing ring or the rim of the cup 32 is inclined downwardly. The drums may be of sufficient length to enable several articles to be packaged simultaneously.