Patent GB-912162-A (GB)
Title: Improvements in or relating to apparatus for treating food
IPC: A23B4/052
Filed: 1960-09-30
Abstract: 912,162. Oven stoves. NORRMALMS INDUSTRIER A.B. Sept. 30, 1960 [Oct. 3, 1959], No. 33706/60. Class 126. [Also in Groups VI, XIII, XXVI and XXIX] Apparatus for treating food, e.g. sausages and other meat products, with air, steam, smoke or other gaseous media, comprises a compartment for the food to be treated, a blower-unit cooperating with the compartment to circulate the treating medium through the compartment and including a reversible motor coupled to a rotatable driving shaft on which a fan provided with radial vanes rotates, and a valve arrangement to reverse the direction of circulation of the treating medium through the compartment comprising a housing partially enclosing the fan and rotatable about the driving shaft in response to a change of direction of rotation of the shaft and a stop arranged to co-operate with the housing to arrest rotation of the housing in each of two alternative operative positions according of the direction of rotation of the driving shaft. Food is treated in the central compartment 2, Fig. 1, of a heat-insulated cabinet 1 by gas circulated by a blower-unit 6 across the central compartment from one lateral compartment 4 to the other, either counter-clockwise (as depicted in Figs. 1 and 2) or clockwise (Fig. 3). Fresh air, steam, smoke or mixtures of these, as the case may be, is introduced through openings 9, Fig. 1, while surplus medium escapes through a valve 12 at a rate corresponding to that of the supply of fresh medium ; tubular gas burners, electric heating elements or cooling coils 10 may be provided for adjustment of the temperature of the medium on entering, but alternatively heating elements and cooling coils may be placed on both sides of the blower-unit under the bottom 5 of the central compartment or built into the walls 3 of the central compartment. The blower-unit comprises a horizontal driving-shaft 13 extending the full length of the cabinet, coupled to a reversible electric motor; the driving-shaft carries a number (Fig. 4, not shown) of axially-spaced centrifugal fan wheels 15, each partially enclosed by trough-like casings 16 mutually interconnected by casings 17 and the housing thus formed by the casings is rotatably mounted on the driving-shaft 13. Thus, on reversing the rotational direction of the fan(s) the housing will also rotate between its two terminal positions (as depicted in Figs. 2 and 3). This rotation is facilitated by the provision of wings or flanges 20a, 20b, upon which the flow of gaseous medium impinges when the reversal is effected; the wings or flanges act also as stops and co-operate with the surroundring walls to prevent excess leakage around the blower-unit. ' The cabinet depicted in Fig. 5 is provided with a central, vertically extending partition 31 so that the gaseous medium may circulate upwards through one-half of the compartment and downwards through the other, and the blower-unit comprises a rotatable cylindrical barrel 21 having broad slots 211 and 21<SP>11</SP> extending peripherally over each one-half of the circumference of the barrel; fresh treating medium admitted through the slots 211<SP>1</SP> is blown into the treating compartments through the slots 21<SP>1</SP> by rotary fan wheels 25 coupled to the rotor 28 of an electric motor 26. The stator 26 of the motor, which has two diametrically opposite projections 29 for cooperation with an abutment 30, enables the barrel 21 when rigidly connected to the stator, to move to and fro by approximately half a revolution on reversal of the rotor, whereby the direction of flow of the treating medium through the compartments may be reversed. Alternatively, the turning of the barrel may be effected by incorporating a simple mechanical gear between the stator 26 and the barrel 21; the gear ratio may be such that a small rotational movement of the stator will be enough to complete the full change of position of the barrel. Smoke may be generated by pressing blocks 35 of wood by cup-like weights 34 against the rotating roller 33; the smoke produced passes a curtain 36 of water and a filtering screen 37 before entering the barrel. Steam or other gaseous medium may be supplied in a similar manner in combination with smoke, if desired, and the circulating gaseous medium may be heated to a suitable temperature. The blower-unit may alternatively be located near the top of or outside the treating apparatus and its driving shaft may be vertically disposed.