JP2805971B2 - Cooker - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooking device having an oven, a grill, a microwave oven and the like, and more particularly to a deodorization and deodorization for purifying and removing smoke and odor discharged during cooking. The present invention relates to improvement of a microwave oven having a function.

2. Description of the Related Art In recent years, there has been proposed a household appliance, particularly a cooking appliance, equipped with a smoke removing mechanism using an oxidation catalyst, reflecting a clean orientation.

Examples of this type of heating cooker include the oven microwave oven shown in FIGS. 4 and 5, wherein FIG. 4 is a sectional view and FIG. 5 is an upper sectional view of FIG. In FIG.
Denotes a heating chamber, which has a heater 2 for cooking, a shelf 3 on which the food is placed, and an exhaust gas passage 4 composed of a plurality of pores. 5 is an opening / closing door. Reference numeral 6 denotes a magnetron for performing microwave cooking.
Is irradiated with microwaves. Numeral 8 is a cooling fan for preventing the temperature of the magnetron 6 and a control circuit (not shown) from rising. The cooling air passing through the magnetron 6 flows into the heating chamber 1 through the hood 9. Reference numeral 10 denotes an exhaust passage for guiding the exhaust gas from the heating chamber 1 to the outside. An oxidation catalyst 11 for purifying the exhaust gas and an auxiliary heater 12 for heating the catalyst are provided downstream of the exhaust gas passage 4 inside the exhaust passage. I have. 13 is an outer casing, 14 is a heat insulating material.

In the above-described configuration, when performing microwave cooking, microwaves are irradiated to the food from the magnetron 6 to be heated, and when performing oven cooking or grill cooking, the magnetron 6 does not operate, and the heater 2 is energized to supply electricity to the cooking chamber. While the inside of the furnace 1 is heated, a part of the cooling air from the cooling fan 8 flows into the cooking chamber 1 from the hood 9, and the heated exhaust gas reaches the exhaust passage 10, passes through the oxidation catalyst 11, and smokes. And deodorization is performed.

Generally, unless the oxidation catalyst is heated to about 300 ° C. or more, its function cannot be sufficiently exhibited. Although there is a limit, the higher the temperature of the catalyst, the higher the activity and the smaller the oxidation catalyst 11. With this configuration, the auxiliary heater 12 is used during cooking.
, The oxidation catalyst 11 is heated by both the heat of the exhaust gas and the auxiliary heater 12, and the temperature of the catalyst can be sufficiently increased. As a result, a small catalyst body can be obtained.

Problems to be Solved by the Invention However, such a conventional cooking device requires an auxiliary heater, so that the cost is increased to realize a control device and a mounting configuration such as insulation.

In the case of a cooker that uses electricity as an energy source, it is necessary to supply sufficient electric energy to a cooking heater in order to heat the food quickly and quickly, but energize an auxiliary heater for heating the catalyst. As a result, the energy of the cooking heater decreases, and the cooking performance decreases. That is, since the cooking time increases and the heating is performed at a low temperature, there is a problem that the finish is not finished.

The present invention has been made to solve the above-mentioned problems, and reduces the heat radiation of a catalyst body heated by a heating source for cooking, thereby eliminating the need for an auxiliary heater, realizing a low cost, and achieving cooking performance, smoke emission, and odor. It is an object of the present invention to provide a heating cooker which is excellent in purification performance.

Means for Solving the Problems In order to achieve this object, a cooking device according to the present invention comprises a heating chamber for storing food, a heating source for food, and an exhaust gas passage provided in a side portion of the heating chamber. An exhaust hole for discharging exhaust gas to the outside, an exhaust duct provided between the exhaust gas passage and the exhaust hole, and through which exhaust gas from the heating chamber passes, and a gas purifying catalyst disposed inside the exhaust duct. And a catalyst holder for holding the catalyst body, wherein a downstream end face of the catalyst holder is provided with a predetermined gap from an end face of the discharge hole, and a space is provided between the catalyst holder and the exhaust duct. A layer is formed, and the cooking exhaust gas is configured to be able to flow into the space layer through the gap,
An ejector hole for sucking air is provided near the downstream end surface of the catalyst holder on the upper surface of the exhaust duct.

The exhaust gas heated by the heating source flows into the catalyst through the exhaust gas through hole, the catalyst receives the heat and is heated, and the exhaust gas oxidized and purified by the catalyst passes through the catalyst holder and the exhaust duct to the exhaust hole. Although it is discharged from the outside, a predetermined gap is formed between the downstream end face of the catalyst holder and the end face of the discharge hole, and a space layer is provided between the catalyst holder and the exhaust duct so that they can communicate with each other. Because of the configuration, a part of the heated exhaust gas also flows into the space layer from the gap, and the temperature of the space layer increases due to the thermal energy of the exhaust gas.
As a result, heat release of the catalyst is prevented by the combined effect of the temperature rise of the space layer and the air insulation effect, and an eject hole for sucking air is provided only near the downstream end surface of the catalyst holder and only on the upper surface of the exhaust duct. Therefore, air is attracted from the ejector holes by the flow of exhaust gas passing through the catalyst body, the flow direction of the exhaust gas is corrected downward by the Coanda effect, and the temperature distribution of the catalyst body is made non-uniform by the draft effect (the upper part has a high temperature, the lower part has the lower part). Becomes low temperature). As a result, the catalyst can be effectively and uniformly heated to the required activation temperature by the thermal energy of the cooking exhaust gas.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a sectional view of an oven microwave oven according to the present invention, and FIG. 2 is a partially enlarged sectional view of FIG.

In the figure, reference numeral 15 denotes a heating chamber for storing food, and a heating source 16 composed of a flat heater for heating the food is provided on an upper surface thereof. An exhaust gas through hole 17 composed of a plurality of pores for exhausting exhaust gas generated during heating and cooking is provided on a side surface of the heating chamber 15, and a predetermined gap is provided downstream thereof to reduce pressure loss. An oxidation catalyst 18 for purifying the exhaust gas by providing a catalyst is fixed by a catalyst holder 19. Here, the catalyst body 18 is made of Cu-Mo-Co on a honeycomb-shaped carrier composed of fibers composed of SiO ₂ and Al ₂ O _3.
It carries a system catalyst. Reference numeral 20 denotes an exhaust duct provided so as to surround the catalyst holder 19, one end of which is in contact with a wall surface of the heating chamber 15, and the other end of which is in contact with an outer casing 22 provided with an exhaust hole 21 for discharging exhaust gas to the outside. . The downstream end face 23 of the catalyst holder 19 is located at a gap 24 from the end face of the discharge hole 21, and a space layer is provided between the catalyst holder 19 and the exhaust duct 20.
25 are formed, and the gap 24 and the space layer 25 are configured to be able to communicate with each other.

The other configuration is the same as that of the conventional example shown in FIG. 4, and the same reference numerals are given and the description is omitted.

Next, the operation of the above configuration will be described. When the food is placed in the heating chamber 15 and the power is turned on to the heating source 16, the food is heated, and when the temperature of the heating chamber 15 is around 100 ° C., the moisture contained in the food is generated as water vapor. At this stage, the cooling fan 8 does not rotate. This is to increase the temperature of the heating chamber 15 efficiently. At this time, the air in the heating chamber 15 expands as the temperature of the heating chamber 15 rises, and the air flows through the exhaust gas passage 17 even if the cooling fan 9 does not rotate. Therefore, the catalyst 18 is heated by the exhaust gas and the temperature gradually rises. In addition, since the space layer 25 is provided, the air layer has an air heat insulating effect, and heat radiation to the periphery of the catalyst body 1 is reduced as compared with the related art, so that the temperature is efficiently increased.

When the temperature of the heating chamber 15 rises to about 300 ° C., the cooling fan 8 operates, and a flow of air from the heating chamber 15 to the discharge hole 21 is generated. At this time, the heated air in the heating chamber 15 flows into the catalyst 18 through the exhaust gas passage 17 and the temperature of the catalyst 18 rapidly rises. Further, as shown in FIG.
Some of the high-temperature exhaust gas that has passed through
25, and the temperature of the air layer 25 rises. That is, the combined action of the temperature rise of the space layer 25 and the air heat insulating effect prevents the heat release of the catalyst 18 and reaches the required activation temperature without the auxiliary heater. As a result, cooking smoke of foods generated from around 300 ° C. is oxidized and purified by the catalyst body 18, and if the exhaust portion including the catalyst body is provided above the heating chamber from the discharge hole 21, the temperature becomes high. The cooked exhaust gas has a reduced specific gravity and flows upward due to the draft effect, and is discharged to the outside from the discharge hole without flowing into the space layer 25, and cannot contribute to prevention of heat radiation of the catalyst body 18. Therefore, the exhaust portion needs to be provided on the side surface of the heating chamber 15.

As described above, according to this embodiment, the space layer 25 is provided by the catalyst holder 19 and the exhaust duct 20 and the catalyst holder 19
Are arranged with a gap 24 therebetween and communicate with the space layer 25, thereby preventing heat radiation of the catalyst body 18 and improving the heat insulation effect by guiding a part of the heat energy of the exhaust gas which has been conventionally discarded outside to the space layer 25. Therefore, the catalyst 18 can be brought to the activation temperature without the auxiliary heater, that is, by utilizing the heat energy of the heating source 16 for cooking. Thereby, a small catalyst body 19 can be realized and an electric circuit for mounting the auxiliary heater,
Cost reduction can be achieved because an insulating configuration is not required. Further, since the heat insulation effect is improved by utilizing the waste heat, the heating and cooking performance is not impaired. Further, since the space layer 25 is provided on the entire circumference of the catalyst body 18, the temperature distribution of the catalyst body 18 can be improved.

FIG. 3 is a sectional view of a main part showing another embodiment of the present invention, in which a downstream end face 23 of a catalyst holder 19 on an upper surface of an exhaust duct 20 is shown.
An ejector hole 26 for sucking air is provided at a position close to the exhaust duct 20. When waste gas passes through the exhaust duct 20, emptying is induced by the ejector effect.

According to this configuration, when the exhaust gas passes through the exhaust duct 20, the air is sucked from the ejector holes 26 and acts on the exhaust gas flow, and the third air is applied by the Coanda effect (jet wall adhesion effect).
As shown in the figure, there is an action to change the flow of the exhaust gas.

In general, when air is heated, its specific gravity becomes smaller and has a property of flowing upward due to a draft effect. That is, the exhaust gas that has passed through the exhaust gas passage 17 mainly passes above the catalyst body 18, so that the temperature of the lower surface portion 18b is lower than that of the upper surface portion 18a of the catalyst body 18, and the effective volume having catalytic activity decreases.

With this configuration, the exhaust gas flows downward as shown in FIG. 3, and there is an effect that the lower surface portion 18a is efficiently heated through the space layer 25 and the effective catalyst volume can be increased.

Effects of the Invention As described in detail above, according to the present invention, the following effects can be obtained.

(1) Since the space layer is provided, the temperature rise of the space layer due to the inflow of the high-temperature exhaust gas and the heat insulation effect of the air in the space layer prevent heat radiation of the catalyst body, and at the downstream side of the catalyst holder,
In addition, since the ejector holes for sucking air are provided only on the upper surface of the exhaust duct, air is drawn from the ejector holes by the flow of the exhaust gas, the flow direction of the exhaust gas is corrected downward by the Coanda effect, and the catalyst body by the draft effect is formed. Non-uniformity of the temperature distribution is prevented. As a result, the temperature of the catalyst body can be effectively and uniformly raised by the thermal energy of the cooking exhaust gas, and the cooking smoke and odor can be effectively oxidized and decomposed without an auxiliary heater.

(2) Since the nonuniform temperature distribution of the catalyst body due to the draft effect is prevented, the active volume of the catalyst increases. As a result,
The purification efficiency is improved, and the size of the catalyst body can be reduced.

(3) Since the temperature can be raised to the activation temperature of the catalyst body by effectively utilizing the waste heat, an auxiliary heater is not required, so that the cost can be reduced and the cooking performance is not impaired.

[Brief description of the drawings]

FIG. 1 is a sectional view of a cooking device showing one embodiment of the present invention,
FIG. 2 is an enlarged sectional view of the essential part, FIG. 3 is an enlarged sectional view of an essential part showing another embodiment, FIG. 4 is a sectional view of a conventional cooking device, and FIG. It is sectional drawing. 15 ... heating room, 16 ... heating source, 17 ... exhaust gas passage, 18 ...
... catalyst, 19 ... catalyst holder, 20 ... exhaust duct, 21 ...
... discharge hole, 23 ... downstream end face, 24 ... gap, 25 ... space layer, 26 ... ejector hole.

──────────────────────────────────────────────────の Continued on the front page (72) Inventor Ikuo Matsumoto 1006 Kadoma, Kazuma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (56) References JP-A-52-30569 (JP, A) JP-A-51-13152 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F24C 15/20

Claims (1)

(57) [Claims] 1. A heating chamber for storing food, a heating source for heating the food, an exhaust gas hole provided in a side surface of the heating chamber, an exhaust hole for discharging exhaust gas to the outside, An exhaust duct provided between the hole and the exhaust hole, through which exhaust gas from the heating chamber passes, and a gas purifying catalyst body disposed inside the exhaust duct and a catalyst holder holding the catalyst body, A downstream end face of the catalyst holder is provided with a predetermined gap from an end face of the discharge hole,
A space layer is formed between the catalyst holder and the exhaust duct, and cooking exhaust gas is configured to be able to flow into the space layer through the gap, and air is supplied to the upper surface of the exhaust duct near the downstream end surface of the catalyst holder. A cooking device with an ejector hole for suction.