Fuente:
WIPO "dairy products"
864,856. Packaging. NATIONAL DAIRY PRODUCTS CORPORATION. Aug. 17, 1959, No. 28066/59. Class 94(1). Packages such as of cheese wrapped in film and enclosed in folded cardboard &c. blanks are subjected to mechanical pressure on all sides while in a chamber under subatmospheric pressure to remove air from them. Apparatus for performing the above comprises a chamber 16 having reciprocatable false sides 31, 34 and base 23 and closeable by a lid 41. The base 23 is raised to approximately the level of the chamber rim and a number of packages 8 arranged on it. Guide rails 88, 89, 92 (the last being shown in a retracted position in Fig. 10) assist in positioning the packages. The base is then lowered, the lid closed and pressure reduced in the chamber. The base 23 and sides 31, 34 move inwards to compress the packages. After a given period the sides 31, 34 withdraw, the lid is opened and the base 23 rises to present the packages for removal. All moving elements of the apparatus are operated by pneumatic or hydraulic piston and cylinder means. Packages which the apparatus is adapted to handle may comprise wrapped cheese wedges assembled in groups separated by partitions 6 in a corrugated cardboard member 1 having a closure sheet 7. The assembly so formed is placed in a partially folded wrapper 9, also of corrugated cardboard, and flaps 10, 13, 14 folded down and secured by adhesive strip 15 and slow setting adhesive, the latter finally setting during compression. Integral tabs may be provided in lieu of the strip 15. The treated package is finally sealed with adhesive strip.