JPH08159475A - Oven for cooking food with hot air injection - Google Patents

Abstract

PURPOSE: To provide a small-sized hot air injection part, prevent a loss of heat and to enable a heating efficiency to be improved by a method wherein a transferring device of a heater is provided with some fine holes for injecting hot air against a transporting device within a heating and cooking chamber and further the surface of the heater is formed with a far-infrared ray radiating surface. CONSTITUTION: In the case that hot air is dispersed from an inlet duct 8 toward a plurality of heaters 10, a pressure at each of the heaters becomes equal from each other, so that hot air can be uniformly dispersed. The heaters 10 are in parallel with a transporting device 2. Even if there occurs a difference in amounts of hot air injection injected from the heaters 10, there occurs no difference in finished baking of a food in response to a location where the food is placed. In addition, since there is provided an outlet duct 9 so as to form a hot air circulating passage not passing through the heating and cooking chamber 1 and an amount of hot air injected into the heating and cooking chamber 1 is reduced, resulting in that an amount of hot air leaked out of the device is reduced. In the case that a piza or the like is heated, an upper-side heater is not provided with a fine hole for injecting hot air, but with a far-infrared ray injection and in turn a lower heater is provided with some fine holes 10 so as to perform a hot air injection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a food cooking oven for heating food by blowing hot air.

[0002]

2. Description of the Related Art As an oven for heating food with hot air jet and far-infrared radiation, there is an apparatus described in JP-A-63-263326. In the case of this device, a duct having a hot air blowing means is provided in a direction perpendicular to the carrying direction, and the hot air is blown into the cooking chamber through the holes provided in the duct by feeding the hot air into the duct. When hot air is blown from a duct with high pressure to a heating chamber with low pressure, if the diameter of the duct is constant, the amount of hot air jetted near the tip of the duct is less than the amount of hot air jetted near the root of the duct. Therefore, there is a difference in baking depending on the place of the food placed on the conveyor. Therefore, the hot-air injection amount is adjusted by making the diameter of the duct thick at the base and thin at the tip, and the hot-air injection unit becomes large.

Further, all of the hot air supplied to the upper and lower ducts is jetted to the heating and cooking chamber, and the hot air is collected from the heating and cooking chamber. The amount of hot air escaping to the outside through the opening of the was increased, resulting in deterioration of working environment and reduction of thermal efficiency.

Further, in the case of the above-mentioned oven, there is a problem that it takes a long time to prepare for heating for raising the temperature from a low temperature state such as starting up to a temperature at which cooking can be performed.

[0005]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to improve the heating efficiency by reducing the size of the hot-air injection unit in an oven in which heating is performed by hot-air injection to prevent heat loss. It is to provide an oven that can improve the environment and shorten the preparation time for heating.

[0006]

[Means for Solving the Problems] A box-shaped heating and cooking chamber for heating food is formed, and a conveying device that horizontally penetrates the heating and cooking chamber is provided. Two heating openings, a combustion chamber provided close to the cooking chamber, an air heating unit with a burner and air flow forming means are provided, and hot air is sprayed onto the food in the cooking chamber to heat the food. In the oven in which the hot air sprayed into the heating cooking chamber is recovered from the suction port connecting the heating cooking chamber and the combustion chamber, in the vicinity of one opening in the upper and lower portions of the heating cooking chamber, connected to the air flow forming means An inlet duct extending in the direction perpendicular to the transport direction,
An outlet duct connected to the combustion chamber and extending in a direction perpendicular to the conveying direction of the conveying device near the other opening in the upper and lower portions of the cooking chamber, and a plurality of thin hot air passages between the inlet duct and the outlet duct. There is a heater to connect with,
On the transfer device side of the heater, fine holes for injecting hot air toward the transfer device in the cooking chamber are provided, and a far infrared radiation surface is formed on the heater surface. Further, for heating pizza and the like, a suction port is provided above the conveying device, a heater provided in the upper portion is not provided with pores, and only a heater provided in the lower portion is provided with pores.

Further, a temperature detecting device is provided in the air heating section and the cooking chamber, an air flow rate adjusting means for adjusting the flow rate of the air formed by the air flow forming means, and a burner combustion control means are provided. When the air heating unit is overheated, the burner combustion is adjusted based on the temperature detected by the temperature detection device installed in the air heating unit, and the temperature detection device installed in the heating chamber during normal operation. Burner combustion control is performed based on the temperature detected at. Further, when the detected temperature is low, the air flow rate is reduced by adjusting the discharge amount adjusting device and the circulation fan rotation speed, and when the temperature is high, the normal air flow rate is obtained.

[0008]

When the hot air is distributed from the inlet duct to the plurality of thin heaters, the pressures of the heaters are equal, so that the hot air can be evenly distributed to the heaters. The heater is installed in parallel with the conveyor, and even if there is a difference in the amount of hot air sprayed from the heater, there is no difference in the baking depending on the place where the food is placed. There is no need to change the diameter. Further, the outlet duct is provided to form a circulation path of the hot air that does not pass through the heating cooking chamber, and the amount of hot air injected into the heating cooking chamber is small, so that the amount of hot air leaking to the outside is reduced. When the amount of food from the top of the food, such as pizza heating, is less than that from the bottom, the heater on the upper side is not provided with holes for hot air injection but only far-infrared radiation, and the heater on the lower side has holes. It is possible to make a difference in the heating amount by providing a hot air jet and to adjust the heating amount by adjusting the size and number of the pores.

The cause of the increase in the temperature rising time is the loss of heat due to the escape of hot air from the opening of the conveying device. When the temperature is low and when the temperature is high, there is a difference in the air flow rate even when the fan is operated, and when the temperature is low, the air flow rate increases and the amount of air escaping from the opening also increases. Since the food is not heated during the temperature rising time, the hot air injection amount may be small, and if the heat loss is reduced by reducing the air flow rate, the temperature rising time becomes shorter. Also, normally, by adjusting the temperature based on the temperature of the cooking chamber, it is possible to maintain an appropriate temperature for heating cooking, but when raising the temperature rapidly, adjust the temperature with the temperature of the cooking chamber. If so, the temperature of the air heating section may rise excessively. Therefore, by adjusting the temperature based on the temperature of the air heating section only when the temperature is raised, it is possible to rapidly heat up to a certain temperature and then to prevent overheating, and in a short time without overheating. It can be raised to the required temperature.

[0010]

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of an embodiment of the present invention, and FIG. 2 is A- of FIG.
A sectional view, FIG. 3 is a sectional view taken along line BB of FIG. 1, and FIG. 5 is a schematic perspective view of a main part of one embodiment. The rectangular parallelepiped heating cooking chamber (1) is provided with a conveying device (2) that horizontally penetrates the heating cooking chamber (1), and an opening (3) is formed on a side surface of a pair of opposing heating cooking chambers. Has been opened. An air heating unit (4) including a burner (5), a combustion chamber (6), and a circulation fan (7) as an air flow forming means is provided on the side of the heating and cooking chamber. Near the one opening (3) at the top and bottom of the cooking chamber (1),
An inlet duct (8), which is connected to the circulation fan (7) and extends in a direction perpendicular to the carrying direction of the carrying device (2), a cooking chamber (1)
An outlet duct (9) connected to the combustion chamber (6) and extending in a direction perpendicular to the transfer direction of the transfer device (2) is provided near the other opening (3) in the upper and lower parts of the inside. . Entrance duct
A heater (10) consisting of five thin hot air passages is provided between the (8) and the outlet duct (9), and the hot air generated in the combustion chamber (6) is circulated fan (7) and inlet duct (8). ), Heater (10),
A first circuit is formed through the outlet duct (9) and back to the combustion chamber (6). The surface of the heater (10) is coated with a far-infrared radiation material, and a large number of pores (11) for jetting hot air are opened on the upper surface of the heater provided on the lower side. A suction port (12) connecting the cooking chamber (1) and the combustion chamber (6) is provided at a higher position than the transfer device (2) on the wall surface of the heating chamber (1) on the combustion chamber (6) side. The second circulation path in which the hot air generated in the combustion chamber (6) returns from the heater (10) to the combustion chamber (6) through the pores (11), the cooking chamber (1), and the suction port (12). Is formed. The air heating part temperature detection device (13) for detecting the temperature of the air heating part and the heating cooking chamber temperature detection device (14) for detecting the temperature of the heating cooking chamber are
Control unit that controls the burner (5) and circulation fan (7)
Connected to (15).

When the food conveyed by the conveyor (2) is heated and cooked, the burner (5) is burned to heat the air in the combustion chamber (6) and the circulation fan (7) is turned on. By rotating, the heated air is sent to the upper and lower inlet ducts (8). The hot air sent from the circulation fan (7) to the inlet duct (8) is the heater connected to the inlet duct (8).
Disperse and flow into (10) to heat the surface of the heater (10). Since the hot air passage in the heater (10) is thin, the hot air flows along the surface of the heater (10), and the heat of the hot air is easily transferred to the heater (10), and the heater (10) is heated. The far-infrared radiation is emitted from the surface of the heater (10) toward the food on the conveyor. Lower Heater (10)
A pore (11) for jetting hot air is provided in the hot air flowing through the heater (10) into the cooking chamber (1) through the pore (11), and the transport device ( 2) Hot air is blown onto the lower surface of the upper food. The jetted hot air passes between the food placed on the transfer device (2), is returned to the combustion chamber (6) from the suction port (12) above the transfer device (2), and the heater (10 ) And reaches the outlet duct (9), the hot air is returned to the combustion chamber (6) through the outlet duct (9). The hot air returned to the combustion chamber (6) is heated again by the heat from the burner (5), and the circulation of the hot air is repeated.

The burner (5) and the circulation fan (7) are control units.
It is controlled by the temperature input to (15). When the temperature is raised from a low temperature state such as at the time of start-up or when stopped halfway, the burner (5) is controlled by the temperature of the air heating unit temperature detection device (13). FIG. 4 shows an air heating part temperature detected by the air heating part temperature detecting device (13) and a heating cooking chamber temperature detecting device (1
It shows the change in the temperature of the cooking room detected in 4). Temperature t1 and temperature t2 are set in the control unit (15), and immediately after the temperature rise is started, the temperature of the air heating unit is the temperature t1.
The burner (5) is continuously burned until Combustion of the burner (5) is controlled so that the heating section temperature is maintained at the temperature t1 from the time when the temperature of the air heating section reaches the temperature t1 until the temperature of the heating chamber reaches the temperature t2. When the temperature of the heating cooking chamber reaches the temperature t2, the combustion control of the burner is changed to the control based on the temperature of the heating cooking chamber, and the combustion of the burner (5) is controlled so that the temperature of the heating cooking chamber is kept at the temperature t2. The temperature of the cooking chamber is also used for controlling the rotation speed of the circulation fan (7), and when the temperature of the heating chamber is low, the rotation speed is controlled to decrease.

[0013]

EFFECT OF THE INVENTION By implementing the present invention, an oven capable of heating in a short time by hot air jetting and far-infrared radiation, the hot air jetting section can be downsized, and the amount of hot air escaping from the cooking chamber can be reduced. Since it can be reduced, the thermal efficiency is improved and the working environment can be improved. Also,
The time required for raising the temperature can be shortened and the heating preparation time can be shortened.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an embodiment of the present invention.

2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a graph showing temperature changes.

FIG. 5 is a schematic perspective view of a main part of one embodiment.

[Explanation of symbols]

 1 Heating / Cooking Room 2 Conveyor 3 Opening 4 Air Heating 5 Burner 6 Combustion Chamber 7 Circulation Fan 8 Inlet Duct 9 Outlet Duct 10 Heater 11 Pore 12 Suction 13 Air Heating Part Temperature Detector 14 Heating Cooking Chamber Temperature Detector 15 Control unit

Claims (4)

[Claims] 1. A transport device that forms a box-shaped heating and cooking chamber for heating food and horizontally penetrates through the heating and cooking chamber, and two places for carrying in and out the food provided on the side of the heating and cooking chamber. An air heating unit having a combustion chamber, a burner and an air flow forming means is provided in the vicinity of the opening and the heating cooking chamber, and hot air is sprayed onto the food in the heating cooking chamber to heat the food and then to the heating chamber. In the oven that collects the generated hot air from the suction port that connects the cooking chamber and the combustion chamber,
An inlet duct connected to the air flow forming means and extending in a direction perpendicular to the transport direction of the transport device near one opening in the upper and lower portions of the cooking chamber, and another opening in the upper and lower portions of the cooking chamber. An outlet duct connected to the combustion chamber and extending in the direction perpendicular to the conveying direction of the conveying device, and a heater that connects the inlet duct and the outlet duct with a plurality of thin hot air passages are provided near the heater. An oven for food cooking by hot-air jetting, characterized in that pores for jetting hot air toward the carrying device in the heating cooking chamber are provided on the carrying device side, and further a far-infrared radiation surface is provided on the heater surface. 2. The hot-air jet food cooking oven according to claim 1, wherein the suction port is provided above the conveying device, the upper heater is not provided with pores, and only the lower heater is provided with pores. An oven for food cooking with hot air jets, characterized by being provided with. 3. A box-shaped heating and cooking chamber for heating food, and a conveying device that horizontally penetrates the heating and cooking chamber, and two places for carrying in and out food provided on the side of the heating and cooking chamber. An air heating unit having a combustion chamber, a burner and an air flow forming means is provided in the vicinity of the opening and the heating cooking chamber, and hot air is sprayed onto the food in the heating cooking chamber to heat the food and then to the heating chamber. In the oven that collects the generated hot air from the suction port that connects the cooking chamber and the combustion chamber,
When a temperature detection device is installed in the air heating unit and the cooking chamber, the burner combustion is adjusted based on the temperature detected by the temperature detection device in the heating chamber during normal operation, and the air heating unit is overheated immediately after startup. In the food cooking oven, the burner combustion is adjusted based on the temperature detected by the temperature detecting device provided in the air heating unit. 4. A transport device that forms a box-shaped heating and cooking chamber for heating food and horizontally penetrates the heating and cooking chamber, and two places for carrying in and out the food provided on the side of the heating and cooking chamber. An air heating unit having a combustion chamber, a burner and an air flow forming means is provided in the vicinity of the opening and the heating cooking chamber, and hot air is sprayed onto the food in the heating cooking chamber to heat the food and then to the heating chamber. In the oven that collects the generated hot air from the suction port that connects the cooking chamber and the combustion chamber,
An air flow rate adjusting means for adjusting the air flow rate formed by the temperature detecting device and the air flow forming means is provided in the air heating unit or the cooking chamber, and the air flow rate is reduced when the detected temperature is low. Characteristic food cooking oven.