JPS6137257Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a steam oven with a movable steaming container that uses a combination of steam and combustion gas for heating.

Conventionally, when confectionery and food materials that have not been heat-treated are steamed, saturated steam or superheated steam has been used.

When using saturated steam, it is called condensation heat transfer,
As is well known, condensation of water vapor dramatically increases the rate of heat transfer, but at the cost of this, the condensed water wets the object to be treated. For example, in the case of food stored in a cup, water drips onto the top of the cup. Since it accumulates, it is necessary to remove or evaporate it.

In order to prevent the formation of water droplets or to remove them by evaporation, it is sufficient to use superheated steam, which was conventionally produced by superheating using an indirect heat exchanger or by squeezing and expanding high-pressure steam. .

Even if steam and combustion gas, such as propane, are mixed instead of superheated steam, a gas (unsaturated gas) having a temperature higher than the dew point is generated, and the same effect can be obtained.

For example, JP-A-55-156545 discloses a method of treating dough for bread, confectionery, etc. with high-temperature steam superheated to the baking temperature at the beginning of the heating and baking process, which falls within the category of superheated steam. contains high-temperature unsaturated gases.

The effects of superheated steam and high-temperature unsaturated gas include, in addition to the above-mentioned water droplet prevention and removal effects, an effect of increasing heat transfer rate due to high temperature. If the heat transfer rate is too fast, the temperature of the surface layer will rise excessively before the center of the material to be processed reaches the appropriate temperature, and if it is slow, the oven volume will become too large, so the optimum range is This range is based on the state of the material to be treated (temperature: in the preheating stage, the faster the heat transfer rate is, the better.
Moisture content: The surface is completely wet. It is desirable to sequentially lower the heat transfer rate according to the so-called constant rate drying period, the partially wet lapse rate first stage drying period, and the dry lapse rate second stage drying period. ) Therefore, when processing with a tunnel kiln method, it is not possible to obtain a high-quality product and it is not possible to downsize the apparatus unless adjustments are made for each position along the direction of movement. Moreover, it is desirable that this type of steam oven be made to be able to process a wide variety of materials, and it is necessary to adjust heat transfer according to the season and temperature, so adjustments can be made for each position. The need will continue to grow.

However, there is no conventional tunnel kiln type steam open that allows the heat transfer rate to be independently adjusted at each position along the direction of movement, which has implications for the quality of food products, miniaturization of ovens, and cost reduction. , the problem remains until now.

The purpose of the present invention is to overcome the above-mentioned problems by changing the amount of fuel, preferably combustion gas such as LNG, LPG, city gas, and water vapor, and their mixing ratio as appropriate depending on the position in the oven. ,
This allows the temperature and water vapor content of the hot water-containing steam gas to be varied to adjust the rate of heat transfer and the rate of water movement within the material for each location and therefore for each finishing stage. The goal is to provide a steam oven that is now available. It goes without saying that heating can be done with steam or combustion gas alone.

Another object of the present invention is to increase the amount of combustion gas in the hot gas at an appropriate time during the steaming operation to add a roasting effect. The purpose of the present invention is to provide a mobile steam opener for steaming containers.

This invention will be specifically explained below with reference to Examples. FIG. 1 is a front sectional view thereof, and FIG. 2 is a side (partial sectional) view schematically showing its internal structure.

The steam open 1 has a horizontal duct-like casing 2 that is long in the rigid direction (transport direction of the steam container), and the steam container is fed into the steam open 1 and transported.
The main components include a conveyor 3 for taking out the steam, a plurality of steam blowing pipes 4 installed in the casing 2, and a plurality of combustors 5a and 5b.

Casing 2 is a nearly horizontal, rigid, duct-shaped hollow box that is insulated with heat insulating material, and is installed at an appropriate distance from the ground. ) is provided with an inlet 6 for feeding the steaming container and an outlet 7 for taking out the steamed container at the other end (right end), and partition doors 6a and 7a are suspended by hinges attached to the upper part of each. In order to minimize air leakage, in this example,
The heights of the portions 6b and 7b near the inlet and outlet are made small to match the height of the steaming container. (If the height of the steaming container is small and the adjacent parts 6b and 7b are quite long, the partition doors 6a and 7a can be omitted.)
A stack 8 with an adjustable damper is protruded from the upper part of the casing 2 to discharge waste gas at an appropriate position, and to maintain the pressure inside the oven 1 to be approximately the same as the atmospheric pressure and to avoid blowing out high temperature gas outside the oven. can be,
Furthermore, a protection plate 2a is attached to the lower part of the side wall of the casing 2 to protect piping for gas and steam and the return portion of the conveyor 3. Similarly, protect plates 2 are placed on the inlet and outlet sides of the oven.
b, 2c are attached. Casing 2 is
Needless to say, it is used to securely attach the above-mentioned piping and conveyor.

The casing 2, protection plates 2a, 2b, 2c include
A viewing window, a peephole, a manhole, a handhole, etc. are provided as necessary, and a drain hole is provided at the bottom of the casing 2, but this is omitted because it is a commonly used means.

As the conveyor 3, a slat conveyor, a net conveyor, etc. are used, and as shown in FIG. It is supported and rotates in the direction of the arrow, and in the conveyance process, the steaming container is conveyed from left to right.

The steaming container is placed on the conveyor 3 in an appropriate manner at the left end of the conveyor 3 in FIG. While being roasted, move to the right and exit through the exit partition door 7a.
It passes through, reaches the right end of the conveyor 3, and is taken out by an appropriate method.

A plurality of steam blowing pipes 4 are arranged in the lower part of the conveyor 3 at an appropriate distance from the conveyance section 3a, and combustors 5a and 5b are arranged above and below at an appropriate distance from the conveyance section 3a. is supported and installed on the wall of the casing 2.

As shown in FIG. 1, the steam blowing pipe 4 is a hollow cylinder with a sealed tip, and a plurality of small holes 4a are bored in the cylinder at appropriate intervals.
Steam is introduced from the steam main pipe 11 via the control valve 11a, and is blown out from the small hole 4a.
It is desirable that the steam blowing pipe 4 is rotatable and that the direction of steam blowing is variable.

The combustors 5a and 5b have a concentric double pipe structure, as the cross section is shown in FIG.
A mixture of fuel such as LPG or city gas and primary air passes through the inner pipe, and secondary air passes through the annular part made up of the inner and outer pipes.
They are mixed and burned in burner sections 5a and 5b. The mixture of fuel and primary air flows through the main gas pipes 12a, 12b.
The secondary air is passed from the inner pipe of the main gas pipe through the control valves 12a and 12b, and the secondary air is passed from the annular part of the main gas pipe to the control valve 12.
a″, 12b″ to the combustor. It goes without saying that replacing the fuel/primary air mixture and secondary air passages will have little effect on the burner's combustion, and there is no harm in using separate pipes instead of double pipes. We do not care about the detailed structure of the system.

A shielding plate 1 is installed at the bottom of the combustor 5a installed at the top.
3 is installed, but its function is to prevent radiant heat from the combustor 5a from being directly applied to the conveyor 3, and is not essential.

Incidentally, rotatable joints 14a, 14b are provided in the casing 2 penetrating portions of the combustors 5a, 5b, so that the direction of the flame of the burners 5a, 5b can be changed.

As explained in the above specific example, the gist of this invention is to include a nearly horizontal duct-like casing having an inlet for feeding the steaming container at one end and an outlet for taking out the steaming container at the other end; a conveyor capable of conveying from the inlet to the outlet; a plurality of combustion chambers each having an adjustable flow rate and connected in the traveling direction of the conveying section of the conveyor at an upper portion at an appropriate distance from the conveying section of the conveyor; a plurality of steam suction pipes, each of which can independently adjust the flow rate, and a plurality of combustors, which are connected in the traveling direction of the conveyor at a lower part thereof at an appropriate distance from the conveyance section of the conveyor; and a plurality of combustors. A steam oven characterized by having:

Since the present invention has the above-described structure, it is possible to perform various types of steaming (roasting) work while the steaming container moves inside the steam open from the entrance to the exit. (nearby) performs steaming using only saturated steam, causes condensation heat transfer to increase the steaming rate, and removes condensed water dripping.
When the temperature of the steaming container increases, the temperature difference decreases, and the effect of condensation heat transfer decreases, heating with high-temperature gas containing steam and combustion gas increases the temperature difference and increases the heat transfer rate. It can be widely used for steaming, steaming, or roasting raw materials, such as drying the container or browning with just combustion gas, improving the type, flavor, appearance,
Products with different moisture contents can be mass-produced.

Furthermore, since combustion gas is directly mixed to raise the temperature of steam, equipment costs are low and thermal efficiency is high.

[Brief explanation of drawings]

Figure 1 is a front cross-sectional view of an embodiment of this invention;
The figure shows a side view (partial cross section) of the internal structure.
It is a diagram. 1...Steam open, 2...Casing,
3...Conveyor, 4...Steam blowing pipe, 5a, 5
b...Combustor, 6...Steaming container inlet, 7...Steaming container outlet, 8...Stack, 9a, 9b, 9c,
9d, 9e, 9f...Sprocket wheel, 1
0a, 10b...Rail, 11...Steam main pipe,
12a, 12b... gas main pipe, 13... hood.

Claims (1)

[Scope of utility model registration request] a substantially horizontal duct-like casing having an inlet for feeding the steaming container at one end and an outlet for removing the steaming container at the other end; a conveyor capable of conveying the steaming container from the inlet to the outlet within the casing; a plurality of combustors each having a flow rate adjustable, arranged in a row in the direction of travel at an upper part of the conveyor at an appropriate distance from the transport part; A steam oven characterized by having a plurality of steam blowing pipes and a plurality of combustors, each of which is independently adjustable in flow rate.