JPS5916715B2 - microwave heating device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a microwave heating device.

Heating methods using microwave power have recently been used in a wide range of fields.

One example is the use of microwave power to heat hamburger bread. This is done by setting up hamburger shops on the streets and selling hamburger buns cut in half and bread perk to customers' orders, heating them up and then sandwiching the hamburger bread between two pieces of bread and selling them as hamburgers. It is something that exists. Conventionally, commercially available microwave ovens are generally used to heat bread. The hamburger bread is then cut into two pieces and the cut sides are pressed against a hot iron plate to brown them. This is because it is difficult to brown the cut surface of bread using microwave power alone. The disadvantages of this method of heating and browning bread are as follows. (Because the heating and browning of bread are separate processes, the equipment for processing them is also separate equipment, which requires a large area to install the equipment.
(2) '0 when the heated item was put in or removed from the microwave oven.
It is often unsanitary to brown the heated items on a hot iron plate, which is done by humans.

(3) Since the microwave oven is a batch type microwave oven, it is not possible to heat the object continuously.

j5 The present invention has been made in view of the above circumstances and provides a microwave heating device suitable for heating bread with microwaves and browning the bread at the same time.

Embodiment υ of the present invention will be described in detail below with reference to FIGS. 1 and 2.

An inlet portion T and an outlet portion 6 for the object to be heated 4 are provided at both ends of the enlarged opening of the inverted quadrangular pyramid-shaped microwave opener 3 to protrude outward. Above the microwave oven 3 in the drawing, there is provided a ceiling oven 9 which has a built-in heater 5 such as an electric heater or a gas burner J5 for browning bread. In order to protect the heater 5 from the microwave power, a shield plate 9 is provided between the heater 5 and the microwave opener 3, which allows the heating wire to pass through and blocks most of the microwave power.
A is provided. Microphone ■0 A rectangular waveguide 2 is fixed below the mouth wave open 3, and a micro-wave oscillation source 1 is connected to this waveguide 2. A drive drum 11 and an idler drum 10 are provided near the inlet T and outlet 6 of the microwave opener 3, respectively, and two metal wire ropes 8 are placed between the drums 10 and 11. It's being thrown around. A sprocket 12 is fixed on the rotating shaft of the driving drum 11, and the two wire lobes 8 are caused to travel via a roller chain 13 or the like by a driving device (not shown). Then, the object to be heated 4 is placed on the wire lobe 8 and the inlet portion 7
The object to be heated 4 is heated and browned by the microwave power and the heat rays radiated from the heater 5 by passing the microwave through the microwave opening 3 to the outlet portion 5. The microwave oven 3 made of a rectangular waveguide has an electric field E surface 31 wall expanded in sequence, and a metal wire rope 8 running parallel to the magnetic interface wall 32 so as to be almost perpendicular to the electric field E. It is provided.

This prevents the metal wire rope 8 from disturbing the microwave electric field. In this embodiment, the magnetic field H-plane wall 32 is also expanded somewhat toward the end, but this is not an essential condition, and various designs can be made depending on the size of the object to be heated. However, the conveyor is not limited to wire lobes, but may also be a thin metal chain.

Next, the reason for using a metal wire rope or a thin chain as a conveyor will be described below.

In our experiments, in order to brown the bread, the distance between the browning surface of the bread and the heater was approximately 20 mm, and in order to brown the bread in approximately 10 seconds, the heater had to produce approximately 6 children of heat. I got the results I needed. By the way, the conveyor material normally used in a microwave heating device is a dielectric material having a small microwave loss coefficient, such as rubber or glass fiber impregnated with tetrafluoroethylene. These materials have a high heat resistance temperature of 240°C. However, the heat generator is 6W/
If a heat ray is emitted with the calorific value of Cli, the belt temperature will be 3
A metal wire rope was used because the dielectric material was not heat resistant as the temperature reached 00°C or higher. In our experiments, we found that the heat resistance limit of a dielectric belt is when the distance from the heater to the belt surface is about 40 degrees, and the heat output of the heater is about 3W. In order to heat and brown the bread, which is the object to be heated 4, using the apparatus according to the embodiment of the present invention, a conveyor drive device (not shown) is driven, the wire rope 8 is run, and the object to be heated is is sent into the microwave oven 3.

At that time, when the microwave power generated by the microwave oscillation source 1 is input into the microwave oven 3 via the waveguide 2, the microwave power is absorbed by the object to be heated 4, and the object to be heated generates heat. At the same time, the radiant heat of the heating device 5 causes the top surface of the bread, which is the object to be heated 4, to brown. Needless to say, the microwave power is not transmitted into the ceiling open 9 due to the shield plate 9a, and the heater 5 stably generates heat without discharging. Generally, it is avoided to run metal such as the wire rope 8 inside the microwave oven 3, but the wire rope 8
If a radio wave leakage prevention mechanism and a discharge prevention device such as a λ/4 chain yoke is used in the portion 3a that penetrates the microwave opening 3, and if proper spacing is maintained so that the wire ropes 8 in the microwave open 3 do not interfere with each other, relatively large microwave power can be generated. It was found that there was no problem in running metal under such conditions, and it did not significantly affect heating efficiency.

By using the apparatus of the present invention as described above, it is possible to simultaneously heat and brown the object to be heated, and to process the object continuously, making it possible to streamline the work process.

In particular, if the loading and unloading of the object to be heated into this device is carried out automatically, there is no need for people to come into contact with the object to be heated, and the heating effect of both microwave heating and radiant heat generated by the heater allows the object to be heated to be heated. It is also very hygienic because it can kill the mold that is present in heated foods.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical cross-sectional view showing one embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view taken along line 2-2 in FIG. DESCRIPTION OF SYMBOLS 1... Microwave oscillation source, 3... Microwave open, 4... Wave heating object, 8... Wire rope, 8...
・Conveyor, 5... Heater.

Claims (1)

[Claims] 1. A microwave oscillation source, a microwave open consisting of a rectangular waveguide into which microwaves are introduced from the microwave oscillation source and at least the electric field E surface is sequentially expanded, and a microwave open provided on the electric field E surface wall of the microwave open. A conveyor made of a metal wire rope or chain is provided with an entrance/exit for conveying the object to be heated, and a conveyor made of a metal wire rope or chain is provided so as to pass through the entrance/exit and be substantially orthogonal to the direction of the electric field E, and is close to the conveyor and not on the side of the microwave oscillation source. A microwave heating device characterized in that a heating source other than microwave power is provided on the opposite side.