| 摘要 |
<p>1507371 Forced-flow ovens ZANUSSI GRANDI IMPIANTI SpA 24 April 1975 [18 May 1974] 17099/75 Heading F4W In a forced-flow oven comprising a combustion chamber 10 housing a burner 13, a food heating chamber 8 and a chamber 9 housing a fan impeller 17, having an inlet 16 in communication with the chamber 8, and having outlets communicating with an oven gas outlet 11 and with the chamber 8; a duct 15 directs a mixture of combustion products and heated air from the burner 13 to the chamber 8, and extends through the chamber 9, whereby the impeller 17 draws the mixture through the duct 15, chamber 8 and inlet 16 and directs the mixture into the chamber 8, towards outlet 11 and into admixture with the flow from the burner 13 to cool the flow. In the form shown, the flow from chamber 9 towards the outlet 11 is subdivided into flows 26, 27 through outlet 11 and duct 15 respectively by impact with a wall 14, which may include one or more baffles (Figs. 4, 5). The flow 27 forms a screen which prevents flow directly from the burners 13 to the outlet 11. A thermostatic device is located in the outlet 11 to detect temperature rise, which will occur if the fan impeller fails, and to cut-off fuel supply to the burner. In another embodiment (Fig. 6), the outlet 11 leads directly from the fan chamber 9, and the duct 15 is perforated so that the gases in chamber 9 flow directly into contact with the flow through duct 15. In the latter embodiment, two impellers 17 may be provided in, chamber 9, with the duct 15 extending between the impellers (Fig. 7).</p> |
