Elektrische Heizeinrichtung fuer verpackte Lebensmittel

摘要

1,180,958. Electric heating. P. TANGUY, P. CARRE, and J. LE BOULBOUECH. 14 Dec., 1967, [15 Dec., 1966], No. 56878/67. Heading H5H. [Also in Divisions G3, H1] A device for heating food contained in packages is automatically controlled in response to the reading of coded irregularities on the surface of the package. A coded food package, Fig. 1, comprises a bottom 1 and a cover 2. The edges of the bottom on which the cover is glued are cut away as shown, a jag 4 determining the heating time and jags 3, 5 set the intensity of heating and control of other apparatus connected with the heating. The coding may also be effected by recessing the bottom or, for cans where indentations are formed to compensate for the partial vacuum created during sterilization, by additional coding indentations formed during stamping. As shown, Fig. 6, a package 12 is introduced into an oven on a support 13 between infra-red emitting elements 14, 15. The oven shell 16 is insulated by glass-wool. The package is introduced into the oven through an insulated door 18, locked by an electromagnet, having a pressure blade 19 retaining the package in place. Each line of indentations on the package 12 is sensed by a feeler 22, pivoted about a shaft 24 and loaded by a spring 25, the tension of which is adjusted by a cross-piece 26 cooperating with a variable stop 27. An end 28 of the feeler 22 bears on an adjustable rod 29 which exerts a load, when the feeler is not engaging an indentation, on a switch 30 controlling resistances 32. The resistances are placed in series when the feeler engages an indentation and are placed in parallel when it does not. The resistances 32, through a capacitive circuit, determine the time of heating of the coded package. The feelers are arranged along the shaft 24 and through a linkage operated by the package, Figs. 7-9 (not shown), are lowered during insertion of the package and only touch the bottom of the package when it is in the stop position. Current for pre-heating the oven is determined by a contact inserting, through an electromagnetic relay, resistances in the capacitive circuit, a lamp being energized on release of the relay to denote the oven is ready for operation. At the end of a heating cycle the door 19 opens, on release of the electromagnetic lock, by the pressure of a bar 39 on the package. In another embodiment, a package, coded as in Fig. 1, is positioned between a pair of highfrequency electrodes, the lower one of which is positionable in dependance on the length of a jag to vary the intensity of heating. Additional feelers, responsive to the package code, are stated to modify the programme of a device for making pancakes. In a further embodiment, the door is retained by an electromagnet against the pressure of a spring, which, when the electromagnet is deenergized, opens the door and ejects the package.