FR2715030A1 - Cooking oven vapour generator with blown burner - Google Patents

Abstract

A cooking oven comprising a cooking compartment capable of receiving water vapour from a vapour generator, the vapour generator comprising a boiler for water which can be heated by means of a heat exchanger through which pass the combustion products from a gas burner of blown type, said heat exchanger comprising a combustion chamber and a series of tubes which connect the combustion chamber to an outlet, the combustion chamber having a first end at which the blown burner is disposed, wherein the combustion chamber has a second end opposite to said first end, connected to the tubes by collector means in such a way that the combustion products flow from the blown burner to the outlet by passing in a unidirectional mode through the combustion chamber.

Description

COOKING OVEN WITH BURNER STEAM GENERATOR

BREATH

  The present invention relates to a steam cooking oven, in particular of the professional and S type, provided with an improved steam generator, of the type

including a blown burner.

  As you know, the cooking ovens of the cited type essentially include a piece of furniture in which are mainly housed a food cooking chamber and a steam generator. The latter is able to produce steam at high temperature, which is sent to the interior of the cooking chamber for food processing. In particular, the steam is produced in the generator by means of a boiler containing water, which is heated through a heat exchanger through which the combustion products of a blown type gas burner. This exchanger generally includes a combustion chamber associated with the burner, as well as a series of tubes able to transport the fumes from the combustion chamber.

  combustion towards an exhaust outlet.

  Normally, the combustion chamber is roughly shaped like a horizontal axis cylinder, with a

  open end and an opposite closed end.

  The open end of the combustion chamber, opposite that which is arranged axially, the blown burner communicates with the inlet of the smoke tubes, while the opposite end, preferably curved, is able to deflect 180 degrees the flow of combustion gases produced by the blown burner. However, in the combustion chamber, the burnt gases circulate according to a flow which extends in the central position from the burner to the aforesaid opposite wall, from where the gases flow again towards the open end, and therefore towards the tubes. of the heat exchanger, with a substantially perimeter flow which encircles the central flow against the current. This composite circulation of combustion products requires the use of a combustion chamber of relatively high diameter, which results in a much too high space requirement for the entire steam generator, and, consequently, for the oven. Cooking. In addition, the reversal of flow of the combustion products mentioned above causes an overheating of the burner and of the adjacent support walls, from which it follows that it is necessary to use means of thermal insulation and / or cooling. costly to minimize damage to various components, including any electronic and / or electromechanical controls. As a result, ultimately, the

  structure of the steam generator is too complex.

  The main object of the present invention is to provide a compact cooking oven, in particular an oven provided with a steam generator with a blown burner, in which the overall dimensions are

reduced.

  Another object of the invention is to provide a cooking oven of the cited type, provided with a steam generator having a particularly simple and economical structure. According to the invention, these objects are achieved in a

  cooking oven comprising a metal cooking chamber

  sure to receive water vapor from a gen-

  steam generator, the latter comprising a boiler

  for water able to be heated by means of

  re of a heat exchanger through which the combustion products of a blown type gas burner pass, said exchanger comprising a combustion chamber and a series of tubes which connect the combustion chamber to an outlet, the combustion chamber having a first end opposite which is blown burner, characterized in that the combustion chamber

  has a second end opposite to said first end

  mite, connected to the tubes by means

  collectors, so that the combustion products

  tion flow from the blown burner to the outlet passing unidirectionally through the combustion chamber. Preferably, means of diversion are

  housed in the combustion chamber.

  The characteristics and advantages of the invention

  will appear clearly on Reading the description

  which follows, given purely by way of nonlimiting example, referring to the appended drawings, in which: FIG. 1 schematically shows in section a top view of a baking oven according to the invention; Figure 2 shows schematically in longitudinal section a preferred embodiment of the

  steam generator provided in the oven of figure 1.

  Referring to the figures, the cooking oven mainly comprises a cabinet 3 provided with a door 4 through which it is possible to access a cooking chamber 5. The cabinet 3 also houses a steam generator 6 having an outlet 7 for steam, communicating

  with the interior of the cooking chamber 5.

  In particular, the steam generator 6 comprises a boiler 8, partially filled with water, from the top of which extends the outlet 7 for water vapor. In a known manner and not illustrated, the boiler 8 is preferably provided with hydraulic connections suitable for the water supply, as well as control means capable of automatically maintaining the level of the water in the boiler, above the '' a predetermined level of security. The water in the boiler 8 is able to be heated by means of a heat exchanger mainly comprising a combustion chamber 9 and a plurality of tubes 10 able to transport, to an outlet 11, the products of -4 combustion from chamber 9. The combustion chamber 9 is formed by a tube, substantially cylindrical, which extends horizontally over the bottom of the steam generator. The tube 9 has a first open end 12 opposite the lacqueLLe is placed a gas burner 13 of the blown type, which is, for example, associated according to a known technique

  per se, to a suitable blower 14.

  According to the invention, the end 15 of the tube 9 opposite the end 12 is connected to the tubes 10, and therefore to the outlet 11, via a manifold 16 or the like. On the contrary, the end 12 of the combustion chamber 9 is in direct communication only with a chamber 17, separate from the outlet 11, which houses the burner 13 and is put into operation.

blower pressure 14.

  Consequently, the products of combustion flow from the burner 13 to the outlet 11, passing through, in a single direction, the entire heat exchanger, in particular the combustion chamber 9. More specifically, the products of combustion flow along the combustion chamber

  9, the collector 16, the tubes 10 and the outlet 11.

  As has also been verified experimentally, due to the unidirectional flow of burnt gases along the combustion chamber, it is possible to achieve this with a passage cross section of the tube 9 significantly reduced compared to traditional solutions, flow reversal. In addition, and this is an advantage, the diameter of the combustion chamber 9 can be correspondingly reduced, reducing the overall dimensions of the entire

steam generator 6.

  In addition, since the combustion products in Chamber 9 are not deflected towards the burner 13, the latter and the adjacent components are subjected to relatively reduced thermal stresses. This is -5 - translates into better reliability of the components, which, moreover, do not require any special precautions

for their thermal insulation.

  The general operation of the cooking oven is substantially traditional and will not be described in detail in 1U. Naturally, the oven described can undergo numerous modifications coming within the scope of

  the invention. For example, the cooking chamber 5 can be of the type, known per se, with combined cooking of food, with steam and with forced convection.

  In addition, inside the combustion chamber 9 are preferably placed diversion means 18, known in themselves and able to regulate, in an appropriate manner, The phenomenon of combustion in

  this same chamber 9, minimizing harmful emissions of U2 gas at exit 11.

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Claims (2)

  1. Cooking oven comprising a cooking chamber (5) able to receive water vapor from a steam generator (6), the latter comprising a boiler (8) for water capable of be heated by means of a heat exchanger through which the combustion products of a gas burner (13) of the blown type pass, said exchanger comprising a combustion chamber (9) and a series of tubes (10) which connect the combustion chamber to an outlet (11), the combustion chamber having a first end (12) opposite which the blown burner is arranged, characterized in that the combustion chamber (9) has a second end (15 ) opposite to said first end (12), connected to said tubes (10) by means of collecting means (16), so that the products of combustion flow from the blown burner (13) towards the outlet ( 11) crossing unidirectionally the combustion chamber (9).   2. Cooking oven according to claim 1, characterized in that in the combustion chamber (9)   are diverted means (18).