JPS6151848B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bread baking oven, and more particularly to a gas-fired bread baking oven for both loaf bread and sweet bread.

Conventionally, electric ovens and gas ovens have been used for baking bread and pastries, but the former requires relatively high costs for ancillary equipment and energy, and the skin of the baked product becomes thick due to excessive drying, making it difficult to satisfy tastes. Recently, gas-fired ovens have been widely used, and the energy cost is about half that of electric ovens, and the moisture in the combustion gas moistens the bread in the oven, resulting in moderately dry baking. It has reached the point where

In conventional gas ovens for baking bread, the burner is placed only below the operating hearth to raise the heat while avoiding overheating. High-temperature air that has been refluxed is blown from above and below the product on the operating hearth (forced convection). If you try to bake sweet bread or bread rolls using this type of gas oven, the color and luster on the top of the product will deteriorate because there is no overheat, and if you bake with forced convection applied, the surface of the product will become too dry and the skin will become thick. For this reason, when forced convection is stopped, a one-sided heating condition occurs in which the heat only increases, resulting in not only frequent operations such as poor baking on the top side of the product, but also problems in baking. There was a problem that it was difficult to avoid product defects and unevenness. In order to solve this problem, if burners are placed both above and below the hearth, if the operation is combined with forced convection when baking bread, the upper surface will become too brown, and if forced convection is stopped when baking sweet bread, the upper temperature will increase. It was impossible to use it for both purposes because the value rose too much.

On the other hand, gas ovens for sweet bread have burners placed both above and below the operating hearth, and gaps between the slats and other components of the hearth are minimized to prevent ventilation between the upper and lower parts of the hearth, allowing the heat below the hearth to be heated. The structure is designed to prevent water from rising upward. This type of oven does not have forced convection, so when baking bread, it not only takes too long to bake, but also tends to discolor the sides.
In addition, even if forced convection is installed, there is a problem in that the hearth interferes and the convection from above and below does not reach the sides of the bread, and this is also one of the reasons why it is impossible to bake both sweet breads and bread. It was hot. That is, in the past, it was essential for bread factories to have two types of ovens installed depending on the type of baked goods.

The present invention overcomes the difficulties of the conventional apparatus as described above, and makes it unnecessary to install two ovens for sweet bread and white bread, making it possible to perfectly bake these different types of products with a single oven. The purpose is to provide a dual-purpose gas oven that can be seasoned.

In order to achieve this objective, the present invention provides burners both above and below the operating hearth, provides high-temperature air through forced convection in the same way as in a bread oven, and provides communication between the lower burner and the hearth. By installing a baffle plate with an opening, heat is stored in the lower part of the hearth, creating an optimal baking temperature environment in the upper and lower parts of the oven, so that both loaves and pastries can be baked. In this case, the arrangement structure of the baffle plate relative to the blow-off pipe should be selected so that the blow-off of the forcedly recirculated high-temperature air is not obstructed by the baffle plate even if the direction of the blow-off port is appropriately changed. is convenient.

In summary, the present invention consists of an oven body, a grid-type moving hearth through which high-temperature air moves longitudinally inside the oven body, and a convection blower that circulates high-temperature air inside the oven and blows the high-temperature air onto the baked product. An oven for baking bread and pastries, comprising: an apparatus, the burners and a lower burner arranged above and below the operating hearth, and a baffle plate installed between the operating hearth and the lower burner and having a communication port. It is something.

A baffle plate can be installed near the blow-off pipe of the oven or convection blowing device according to the present invention so that there is no problem in changing the blowing direction of high-temperature air from the blow-off port.

Embodiments of the invention will be described in detail below with reference to the accompanying drawings.

Figure 1 shows a conventional gas oven for pastry bread, and Figure 2 shows a conventional gas oven for bread.As mentioned above, it has been difficult for the bread making industry to install both series together. It was essential. The bread oven 1 shown in FIG. 1 defines a furnace chamber with an oven top wall 2, a bottom wall 3, and side walls (not shown), and a hearth 4 extends in the longitudinal direction (in the direction of arrow A) within the furnace chamber. Runs endlessly.
The hearth 4 is generally made of an endless belt, called a slat, attached to a moving chain, as shown in FIG. 3a, which is made by bending a flat steel plate to minimize the gap. Furthermore, as shown in Figure 3b, a model is also used in which the sides of thick steel plates are cut diagonally and connected, and the gaps attached to the movement chain are made even smaller to block ventilation in the hearth and prevent heat from rising. . The hearth 4 is driven by a drive wheel 5, for example of the sprocket type.

A moving hearth 4 in the pastry oven 1 (in this case refers to the hearth moving upward on which the spreading plate 9 is placed)
Burners 7 are arranged above and below at approximately predetermined intervals, and heat is applied to the product on the spread plate 9 from above and below, and the burners on the top burn it in a manner that colors it with radiation. Zone partition plates 8 may be provided in the furnace at appropriate intervals in the longitudinal direction to facilitate temperature control of the high-temperature air. When bread is baked in the sweet bread oven shown in FIG. 1, the coloring of the product is poor, especially on the sides, and the baking time is extremely long.

Fig. 2 shows a gas oven 1' for bread, in which the burner 7 is arranged only under the operating hearth 4, and high-temperature air convection tubes 6 are installed at appropriate intervals on both sides of the operating hearth 4. Furthermore, a zone partition plate 8 largely divides the baking area within the oven 1' in the same manner as described above. The operating hearth 4 is a case 9'
In order to thoroughly toast the whole surface of the loaf of bread inside, especially the sides, a material is used that allows high-temperature air to easily pass through so that the heat from the burner 7 located only on the lower side also hits the side of the case 9'. Usually, inside the furnace 4, a lattice-like structure called a grid is used, which is made by combining round steel and interconnecting them, as shown in Fig. 3c. The tube 6 for high-temperature air convection receives high-temperature air forcibly sucked in by a fan 20 from inside the furnace through an in-furnace duct 15 and a suction duct 18 through a passage 16 in the furnace side wall, and receives it from a small hole 12 connected to the tube surface. Case 9' blows high-temperature air as blowout F onto the upper and lower surfaces of the hearth.
Heat is also supplied to the sides. This allows the lower burner 7
In a chisel oven, increase the heat by increasing only the top heat to prevent uneven coloring (Figure 4). In FIG. 4, the tube 6 has one end loosely fitted into the right side wall as if it were a header 14, and a tube rotation nut 1 at the other end.
3 with a suitable jig and rotated, the direction of the small hole 12 and the direction of the air outlet can be freely adjusted with respect to the hearth 4 whose side end is supported by a roller chain 10 and runs on a track rail 17. being done.

When baking sweet breads and rolls in the gas bread oven 1' shown in Figures 2 and 3, the color and luster of the products are poor because there is no overheat while forced convection of high-temperature air is applied through the tube 6. In order to avoid this, the surface of the product becomes over-dry, and conversely, when forced convection is stopped, hot air rises through the hearth and passes through the cuts in the rolling plates (gaps between the rolling plates), causing the top of the product to burn. When products are charged in rows in succession, the rise of the lower flames is blocked, causing only the lower flames to become stronger, resulting in poor baking on the upper side of the products. Therefore, attempts were made to install burners above and below the hearth in an oven equipped with a forced convection device, but this resulted in the problem that the top surface of the product would become too brown when baking bread.

FIG. 5 shows a partial side sectional view of a bread baking oven 30 for both loaf bread and sweet bread according to the present invention. The oven 30 defines a furnace chamber with a top wall 31 in which a heat insulating material 33 is wrapped with an outer plate 32, a bottom wall 31' similar to the same, and side walls (not shown), and the inside of this furnace chamber is shown in the direction of arrow A as described above. Grit type operation hearth 3
4 are arranged as if running endlessly. The burners 37 are arranged perpendicularly to the longitudinal direction of the oven at appropriate intervals in both the upper and lower parts, and the convection blowing tubes 36 for hot air are also arranged perpendicularly to the longitudinal direction of the oven at appropriate intervals. ing. A blowout port is opened on the surface of the tube 36, and convection is made to blow out in the direction F from above and below.
The pipe-shaped burner 37 surface may also be of a type having continuous pores. In FIG. 5, the baffle plate 3 is placed so as to cover the lower burner 37 at the middle stage of the oven.
5 is provided. It is preferable that the baffle plate 35 is formed by bending a plate-like material such as metal and having a slit-like or small-hole-like upper and lower communication opening or gap 40 that extends to the entire width of the oven. Further, it is desirable that the baffle plate 35 be bent so as not to block the outlet of the lower convection outlet tube 36 within its rotation range. Directly above the upper burner 37 is provided a heat shield 38 for the flame tip, which is made of angle iron or the like and is attached horizontally.

According to the above configuration, although the baffle plate 35 in the gas oven 30 according to the present invention opens the gap 40, it cuts the oven vertically, and therefore, during combustion in the lower burner, the hot air generated by the combustion gas The heat is stored under the baffle plate 35 and then passes through the gap 40 and hits the spreading plate or case 39 on the hearth, and the radiant heat of the upper burner 37 and the heat of the convection air from the upper convection blowing tube 36 are absorbed by the baffle plate 35. The heat is reflected to some extent and can be transferred to the product on the hearth surface.

The above-described dual-purpose oven according to the present invention has a hearth that is easy to ventilate high-temperature reflux air of the grid type used exclusively for bread ovens, and has barteaus arranged above and below the hearth, particularly between the lower burner and the hearth. Baffle plates with narrow or small communication holes 40 are arranged in a row to act as an obstacle to excessive heat loss to the upper part of the oven or as a heat storage body in the lower part of the oven, and to further equalize the temperature inside the oven, The outlet of the high-temperature convection tube from below is installed so that the direction can be changed freely to allow high-temperature air to pass through. Therefore, when using the oven of the present invention for baking bread, the upper burner is turned off and the convection fan is operated to blow high-temperature convection onto the product from above and below the hearth. By stopping the original fan and igniting both the upper and lower burners instead and adjusting their combustion separately to create the optimal baking conditions, both can produce high-quality baked bread in continuous operation. It is.

As described above, the present invention incorporates a unique configuration into a bread baking oven, eliminates the need for two separate conventional ovens for baking white bread and ovens for baking pastries, and enables a simple system with a single system. It is designed so that it can be freely switched to any purpose by operation, and by switching, the optimal firing conditions can be achieved according to each purpose.
This makes it possible not only to reduce the equipment and the area it occupies by almost half, but also to reduce the amount of fuel required and to produce homogeneous, high-quality fired products.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view schematically showing a conventional gas oven for pastry bread, Fig. 2 is a side sectional view schematically showing a conventional gas oven exclusively for bread, Fig. 3a,
b and c are examples of constituent pieces of the hearth, Fig. 4 is a detailed cross-sectional view of a conventional bread oven with the burner omitted, and Fig. 5 is a partial side view of a food and confectionery oven according to the present invention. FIG. 30... Oven, 34... Operating hearth, 36...
... Convection blowing device (tube), 37 ... Burner, 35 ... Baffle plate, 40 ... Communication port.

Claims (1)

[Scope of Claims] 1. An oven body, a moving hearth having a structure through which high-temperature air moving longitudinally inside the oven body can easily pass through, and a moving hearth that circulates the high-temperature air in the oven and directs the high-temperature air to the product to be baked. a convection blowing device that sprays the air, upper and lower burners arranged above and below the operating hearth, respectively, and a baffle plate installed between the operating hearth and the lower burner and having a communication port. A bread baking oven that can be used for making white bread and pastries. 2. In the oven according to claim 1,
A bread-baking oven for bread and sweet bread, characterized in that the baffle plate is installed in the vicinity of the blow-off pipe of the convection blow-off device so as not to interfere with changing the blowing direction of high-temperature air from the blow-off port.