DE3216008C2 - Oven with heat storage - Google Patents

Abstract

An oven with at least one stove and a heat accumulator and a heating medium channel is created. To save energy, the heat accumulator is subdivided into areas (4, 5) so that, in spite of the minimum temperature of the heat accumulator corresponding to the baking temperature, only the energy corresponding to the expected baking volume has to be used.

Description

The invention relates to an oven according to the preamble of claim 1.

There has always been a need to use as little energy as possible when baking. To this Purpose was created, for example, in ovens with several cookers, to switch off some cookers, if these are not required for the respective baking process. One wanted for such a Cooker at the same time use the advantages of a heat storage device, so there was the possibility of energy saving very reduced, because the heat storage, which was designed for the entire furnace, had to be independent of the number of stoves actually used are heated to a minimum temperature in order to ensure a flawless To achieve baking. In the same way, the advantages of a heat accumulator could then not be exploited if an oven is used for several consecutive times, for example during the weekend Loadings, on the other days, however, for considerably less and perhaps only for a single one Charge was used. In the latter case, too, the heat accumulator had to be set to a minimum temperature be heated to produce a sufficiently high temperature for proper baking to be able to.

From the book "5000 year oven" by Blümel-Boog, Deutsches Brotmuseum e.V., Ulm, there is an oven known according to the preamble of claim 1, in which the air flow by means of a flap either can be returned to the baking chamber through the memory or via a bypass, in order to set the baking chamber temperature to control. Although this allows energy to be saved, the entire memory must also be heated to a minimum temperature here in order to generate a sufficiently high baking temperature can.

From DE-AS 25 28 435 an oven is known in which the oven temperature is controlled by the Flow through the heating gas ducts surrounding the baking chamber can be regulated. Furthermore, the

ίο Heating gas supply completely shut off by flaps will.

In the case of the furnace according to DE-AS 15 79 958, finally a second storage tank can be connected upstream of the storage tank, which controls the inlet temperature of the storage tank raises and enables the generation of a hotter mixed air. The two stores are not in terms of temperature isolated from each other. A switching possibility of the memory as in the invention is not with these memories possible.

The object of the invention is to create a baking oven of the type described at the outset, with which various Operating modes such as different numbers of loading processes or during operation only single cookers in ovens with several cookers a significant energy saving is possible.

This object is achieved by an oven according to the preamble of claim I, which according to the The invention is characterized by the features of the characterizing part of claim 1.

jo Other features and usefulness of the invention result from the description of exemplary embodiments on the basis of the figures. From the figures shows

1 shows a cross section through a schematically illustrated oven with two cookers; and

2 shows a schematic representation of a cross section by a rack oven with heat storage.

In the following, the first in FIG. 1 described embodiment shown. The oven 1 includes two stoves 2, 3 and a heat storage unit with a first area 4 and a second area 5. The heat accumulator 4, 5 is connected to the herds 2, 3 via a heating medium duct 6. The heating medium duct comprises one of the heat accumulator 4, 5 leading to the herds 2, 3 flow section 7 and one of the herds 2, 3 to the heat accumulator 4, 5 leading return section 8. In the flow section 7 is a circulation device 9 provided with a circulation fan 10, through which the heating medium in the heating medium duct 6 can be circulated.

The flow section 7 ends with respective feed lines 11, 12, 13, 14 to the herds 3 and 2 at their respective bottom and top surrounding sections of the heating medium channel. Each of the sections ends from another end via leads 15, 16; 17,18 in the return section 8. In each supply line and Valves 19, 20 are provided in each discharge line, via which the feed for regulating the respective lower heat or top heat can be set for each stove.

The two areas 4, 5 of the heat accumulator are designed to be separate from one another and are separated from one another heated. The first area 4 is on the input side via feed lines 21 with the return section 8 and on the output side via discharges 22 with the flow drain

b5 section 7 of the heating medium channel 6 connected.

In the direction of flow downstream from the supply lines 21 leading to the first region 4 is the return section 8 of the heating medium channel 6 via supply lines 23

out on the input side in the second section 5 of the heat accumulator. The circuit is over at the exit side discharged discharges 24, which open into the flow section 7, are closed. Between the supply lines 21 to the first area 4 and the supply lines 23 to the second area 5 or the corresponding leads Check valves 25, 26 are provided in each case 22 and 24. The shut-off valves 25, 26 are via a servomotor 27 or via a facility not shown by Adjustable by hand.

In Fig. 1 is in addition to the Heizmediumkana! a separate heating device 28, 29 is also provided, with which direct heating of the stove is possible independently of the storage heater. This heater 28, 29 can be designed in a known manner.

Temperature sensors 30, 31 for measuring the temperature of the upper heat and temperature sensors 32, 33 for measuring the respective temperature of the lower heat are provided for each oven. The output signal of the respective temperature sensors is fed via controllers to the respective servomotors 34-37 , by means of which the associated valves 20 and 19 can be controlled.

The respective hotplates 38,39 are designed so that they themselves have the lowest possible heat capacity. For example, they are preferably made of one 2 mm thick sheet steel designed as a baking tray.

The above-described device from the herds and the heat storage is as shown by one Surrounding thermal insulation compound 40 so as to prevent radiation.

The storage capacity of the heat accumulator 4.5 is dimensioned so that the oven I with all stoves 2, 3 in Can be operated at full capacity. For this purpose, both areas 4, 5 of the heat accumulator are in It is heated up at night and the heat is then fed to the stoves during the baking time. Since the Hotplates 38, 39 themselves have a low heat capacity, the heat transfer is quick and loss-free possible. The desired lower and upper heating temperature is set via the temperature sensors 30-33 regulated.

Is it now intended, for example, on certain working days, If only part of the oven range is to be used, then only the first area 4 of the heat accumulator will be used heated up during the night. The second area 5 is not heated, and the corresponding one Part of the heating medium channel 6 is switched off via the valves 25, 26.

Even in the event that on certain days all of them Stoves of the oven are to be used, but only a part of that which has to be carried out in full operation Loads of the oven are to be baked, only the first area 4 is also heated and the second area is switched off in the manner described above. The first area is always on one of the Baking temperature corresponding storage temperature heated up. Because the second area is no longer heated must be, considerable energy is saved. Of course, the two are separated from each other t> o usable areas of the heat accumulator are thermally insulated from one another.

In Fig. 2, an oven 4J is shown which, instead of the several cookers open a baking space through which hot air flows horizontally to accommodate a rack shows. Those of the F i g. I corresponding parts are designated by the same reference numerals. The oven 41 has a baking chamber 42. which is designed to receive a stick 43. The rack 43 carries in Usually a number of baking product carriers 44, 45 arranged one above the other. The lead section 7 of the The heating medium channel 6 opens into the side of the oven as in the case of a conventional circulation heating system of a rack oven Oven. On the essentially opposite side, the return section 8 is on the side wall connected. While in the embodiment described with reference to FIG. 1, a closed There was a heating medium duct and thus different heating media could be selected, takes place here in the usual way direct heating through direct contact of the heating medium with the baked goods during the horizontal flow of the heating medium through the baking chamber. The heating medium is in this case be in the usual way in the heat storage air heated.

Although this is shown in FIG. 2 is not shown. can, as in the case of the herds in FIG. 1, on the input side and / or on the output side 42 valves on the baking chamber and if desired a thermostat control can be provided in order to adjust the flow of the heating gas medium.

The storage capacity of the heat accumulator consisting of the first and the second area 4, 5 is like this dimensioned that the heat accumulator heated up during the night is sufficient for the full operation of the oven 41 can give off required heat during baking. Is now to be expected that in relation to the If only one or a few loads are to be baked on a day at full operation, then only the first one will be baked Area 4 of the heat storage tank to the full storage tank temperature corresponding to the baking temperature during the night heated up. The second area 5 remains switched off and via the valves 25, 26 from the heating medium channel 6 separated. In this way it is achieved that considerably less energy is used and nevertheless a perfect baking result can be achieved.

In the above embodiments, the heat storage each formed from a first and a second area 4, 5. In principle, it is possible to use the Subdivision not only into two but into several thermally insulated against each other and in the heating medium duct 6 areas connected in parallel to be subdivided. The individual areas are then each separate can be heated and switched on individually or in combination with one another in the heating medium duct. To this In this way, depending on the expected baking performance, desired amounts of heat can be provided.

For this purpose 2 sheets of drawings

Claims (5)

Patent claims: 1. Oven with at least one stove or a baking chamber, a heat store and a via the heat accumulator and the lower and / or upper side of the stove or through the baking chamber leading heating medium channel with a flow section and a return section, thereby characterized in that the heat accumulator has a first area (4) and at least one against it thermally insulated second area (5), which can be heated separately from one another and individually or in Combination with one another between the flow section and the return section can be switched on. 2. Oven according to claim 1, characterized in that that the first and the second area (4, 5) are connected in parallel between the flow and return sections are. 3. Oven according to claim 2, characterized in that in which the second area (5) with the line section connecting the heating medium duct (6) to a valve (25, 26) for switching it off Area is provided. 4. Oven according to one of claims 1 to 3, characterized in that at least two cookers (2, 3) are provided, the baking temperature of which can be set separately from one another. 5. Oven according to one of claims 1-4, characterized in that the stove or the cookers (2, 3) or the baking chamber (42) via the heat storage (4, 5) and / or additional direct heating (28,29) are heatable.