JPH0811029B2 - Tunnel kiln for baking sweets and bread - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tunnel kiln for baking sweets and breads.

(B) Conventional technology Conventionally, an efficient tunnel kiln has already been developed for baking baked confectioneries.

(C) Problems to be solved by the invention However, in the conventional firing kiln, an electric resistance heating element, a gas burner, or the like is used as a heat source. In addition to increasing the electrical resistance heating element, heating is performed by near-infrared radiation emitted from the heating element, and in the ultraviolet region emitted from flame in the gas burner, etc. The surface of the object is heated, and the inside of the object to be fired is heated by heat conduction.

On the other hand, the material to be baked is mainly made of starch, sugar and water, and these materials have low thermal conductivity,
Furthermore, since the material is formed into a sponge shape, the material has an extremely low thermal conductivity. For this reason,
There is a drawback that a large temperature difference occurs between the surface and the inside of the object to be fired, so that the surface is overbaked and the inside is unbaked.

If the baking temperature is lowered to try to avoid the above drawbacks by slowly baking, the dough becomes too dry and the flavor is lost.

(D) Means for Solving the Problems In the present invention, the object to be fired is to be fired by the upper and lower heat sources arranged above and below the carrier while the object to be fired is being conveyed by the carrier. In the configured tunnel kiln for baking confectionery and bread, a ceramic far-infrared radiation plate is placed above the upper heat source with an appropriate distance from the object to be baked, and the ceramic far-infrared radiation plate is made of aluminum alloy. We provide a tunnel kiln for baking confectionery and bread, which is a ceramic far-infrared radiation surface with a metal oxide and far-infrared radiation material particles coated on the underside of a metal substrate using a binder to make a rough finish coating by a melting method. It is something to do.

(E) Action In this invention, far infrared rays from the ceramic far infrared radiation plate above the inside of the tunnel kiln heated by the upper heat source penetrates into the inside of the dough and directly heats the inside of the dough, The dough is heated almost uniformly on the surface and inside.

The far-infrared ray used here has a wavelength of 5 to 15 μm, and the far-infrared ray in this band excites the rotational vibration of the dough material molecules to heat the dough itself. The longer the wavelength, the longer the wavelength. There is little attenuation in the middle, and the reaching distance to the inside of the cloth becomes large, and this wavelength and intensity can be adjusted by controlling the radiation surface temperature of the ceramic far infrared radiation plate.

(F) Effect According to the present invention, the ceramic far-infrared radiation plate is disposed above the inside of the tunnel kiln at a proper distance from the object to be fired on the transfer device and the radiation plate. While being transported in the tunnel kiln by the transport device, it will be fired by appropriate irradiation of far infrared rays and heating according to the conventional method, the inside will completely pass through the fire, and the surface will have an appropriate burn color. There is an effect that a product can be obtained. Moreover, since the aluminum alloy is used for the metal substrate of the ceramic far-infrared radiation plate, and the radiant surface is used for the rough surface finishing, the temperature distribution of the radiant plate is made uniform and even in each part of the furnace. It has the effect of emitting far infrared rays of wavelength and intensity.

(G) Embodiments The embodiments of the present invention will be described in detail with reference to the drawings.
(A) shows a tunnel kiln for baking sweets and breads, and a kiln (4) having a substantially rectangular cross section with a wall body in which a heat insulating material (1) is covered with inner and outer covering plates (2) and (3). ) And the same kiln (4)
Is horizontally installed on the leg part (5), the carrier device (6) is inserted into the kiln body (4), and the carrier surface (7) of the device (6) is inserted.
The upper and lower heat sources (8) and (9) are arranged above and below the substrate so that the material to be fired placed on the same surface (7) is conveyed and fired.

Electric resistance heating elements such as nichrome wire are used for the upper and lower heat sources (8) and (9), and 6 pieces each are placed inside and below the kiln body (4) in the longitudinal direction of the kiln body (4). The temperature of each heat source (8), (9) is controlled by an external controller.

In particular, a ceramic far-infrared radiation plate (11) is horizontally stretched above the upper heat source (8) with a hanging metal fitting (10) at a predetermined interval. The radiation plate (11) is made of an aluminum alloy. On the lower surface of the metal substrate (12) made of metal, metal oxides such as silicon oxide, boron oxide, aluminum oxide, sodium oxide, and titanium oxide, and far-infrared radiation material particles such as rare earth oxides are bound with sodium silicate. As a ceramic far-infrared radiation surface (13) by coating with a thermal spraying method, the radiation surface (13) is heated by near infrared rays and convection from the heat source, and is emitted from the radiation surface (13). It emits far infrared rays.

Since the metal substrate (12) of the ceramic far-infrared radiation plate (11) is made of a highly heat-conductive aluminum alloy, the temperature distribution of the radiation plate (11) is made uniform, so that radiation is emitted from the radiation plate (11). The wavelength and intensity of the far infrared rays generated are
It is uniform over each part of 3).

For coating the far-infrared radiation material, a construction method such as enameling can be used. The point is that the surface of the metal substrate can withstand high temperatures and the heat transfer from the substrate to the same material is in good condition. Should be attached. However, in order to promote the scattering of the emitted far-infrared rays and make the far-infrared intensity in front of the radiation surface uniform, it is desirable that the radiation surface is a rough surface. From this point, in this embodiment, the radiation surface is a rough surface. It employs a thermal spraying method that finishes with.

The conveyor device (6) supports the pulleys (15) on the frame bodies (14) extending outward from the front and rear ends of the kiln body (4), respectively, so that the pulleys (15) are endless. It is constructed by suspending the carrier strip (16) of
Chains with attachments for transportation are arranged on the left and right side edges of the strip (16), and the chains are connected by a large number of short-faced steel plates to form the upper surface of the steel plate as the transportation surface (7). Yes,
In addition, as the type of the transfer device (6), there are a type such as a net conveyor and a steel belt conveyor.

In the figure, (17) is a guide rail for preventing the conveyor belt (16) from hanging, (18) is a vertically movable partition plate for dividing the inside of the kiln (4) into three zones, and (19). ) Indicates a motor for driving the transfer device (6).

[Brief description of drawings]

Fig. 1 is a longitudinal sectional view of a tunnel kiln according to the present invention (I-I sectional view of Fig. 4). Fig. 2 is a transverse sectional view of the same (II-II sectional view of Fig. 5). Partial cross-sectional view of the infrared radiation plate FIG. 4 is an overall plan view of the tunnel kiln according to the present invention FIG. 5 is an overall side view of the same (1): Tunnel kiln (6): Conveying device (8), (9) : Upper and lower heat sources (11): Ceramic far infrared radiation plate

Continuation of the front page (56) Reference JP-A-54-17172 (JP, A) Actually opened 60-179182 (JP, U) Actually opened 58-91611 (JP, U) JP-B-60-40573 (JP , B2) Microfilm (JP, U) Jpn. App. No. 56-187586 (Jp. U), which is a photograph of the contents of the specification and drawings attached to the application of Jpn. A microfilm (JP, U) of the contents and drawings attached to the application of Kaisho 58-91611)

Claims (1)

[Claims] 1. A transfer device (6) is used to transfer an object to be fired, while upper and lower heat sources (8) and (9) disposed above and below the transfer device (6) to fire the object to be baked. In the tunnel kiln (A) for baking confectionery and breads configured to perform the above, a ceramic far-infrared radiation plate (11) is arranged above the upper heat source (8) with an appropriate distance from the object to be baked. Moreover, the ceramic far-infrared radiation plate (11) is coated on the lower surface of the metal substrate (12) made of an aluminum alloy with a metal oxide and far-infrared radiation material particles by using a binder to make a rough surface coating. Ceramic far infrared radiation surface (1
3) A tunnel kiln for baking confectionery and bread.