JPH06103099B2 - Hot air circulation cooker - Google Patents

Description

Description: [Object of the Invention] (Industrial field of application) The present invention relates to a hot-air circulation type cooker in which hot air is circulated in a heating chamber using a centrifugal fan for heating and cooking.

(Prior Art) In a hot-air circulation type microwave oven (cooker), a casing 2 is provided on the outer surface of the rear wall of the heating chamber 1 as shown in FIG. There is one in which a fan 3 and a heater 4 are provided.

In such a microwave oven, conventionally, as shown in FIG. 6, a suction port 5 (consisting of a large number of punching holes) is provided in the center of the rear wall, and the suction port 5 is blown to even upper and lower positions. A structure in which the outlets 6 (consisting of a large number of punching holes) are formed in strips is adopted.

Specifically, in the casing 2 of the rear wall, the suction port 5 and each outlet
A fan chamber communicating with 6, 6 is formed, and a hot air circulation fan 3 is provided in the fan chamber so as to face the suction port 5 as shown in FIG. A structure in which a substantially annular heater 4 is disposed between and is adopted. However, the hot air circulation fan 3 is rotated by a fan motor 3a provided outside the casing 2.

Then, by operating the hot air circulation fan 3 and the heater 4, the air in the heating chamber 1 is sucked from the suction port 5 to heat it into hot air, and then it is blown into the heating chamber 1 from the outlets 6 and 6. The hot air is circulated.

Reference numeral 8 denotes a main body of the microwave oven, and 9 denotes a door for opening and closing the opening of the heating chamber 1.

However, these microwave ovens have a hot air circulation fan 3
Has a problem that the hot air from the air outlets 6, 6 is blown toward the rotational direction side while being biased toward the rotational direction.

(Problems to be solved by the invention) For this reason, food products (not shown) using a rotating dish
The type that tries to cook is still good, but the square shelf
The type in which 10 is provided on the peripheral wall of the heating chamber 1 in two stages (between the suction port 5 and the outlets 6 in the upper and lower stages) to enable large-scale cooking at one time is Burn unevenness is likely to occur due to the unbalance of the hot air amount on the left and right of 6. In particular,
When the rotation direction of the hot air circulation fan 3 is left (see the arrow in FIG. 7), the left side of the upper outlet 6 indicated by A and the right side of the lower outlet 6 indicated by D are other B and The amount of hot air tends to increase as compared with the portion indicated by C, and the uneven heat generated uneven baking of the food on the shelves 10,10.

The present invention has been made in view of such problems, and an object thereof is to provide a hot air circulation type cooking device capable of improving uneven heating.

[Structure of the Invention] (Means and Actions for Solving Problems) The present invention is designed to traverse the inner surface of the casing 2 facing the air outlet 6 to a portion opposite to the rotation of the centrifugal fan 3. The first airflow direction plate 15 is provided so as to project, and the first airflow direction plate 15 is connected to the first airflow direction plate 15 and is inclined toward the axial center portion of the centrifugal fan 3 in the inner surface portion between the heater 4 and the fan outer peripheral portion. The second wind direction plate 16 is provided so as to project the air from the centrifugal fan 3 toward the fan reverse rotation direction side of the air outlet 6 to make the amount of hot air uniform.

(Embodiment) Hereinafter, the present invention will be described based on an embodiment shown in FIGS. 1 to 4. However, in FIG. 1 to FIG. 4, the same parts (or parts) as the parts (or parts) described in the above-mentioned “Prior Art” are given the same reference numerals, and the description thereof will be omitted. Sections will describe different parts.

That is, one embodiment is different in the structure that guides the air from the hot air circulation fan 3 toward the fan reverse rotation direction side of the discharge port 6 and in the dimension related thereto. Here, first, in terms of the structure in which the wind is guided in the reverse rotation direction of the fan, 15 is the first
And 16 is a second wind direction plate.

The wind direction plate 15 is formed in a triangular shape corresponding to the inclined portion 2a that guides the blowing air of the casing 2. And this wind direction board 15 is, as shown in FIG. 1, FIG. 3 and FIG.
On the inner surface of each inclined portion 2a of the casing 2 facing the air outlet 6, two B and C (opposite to the rotation direction of the fan) side where the amount of hot air is small are point-symmetrically projected two by two. Has been done. For details, for each of the wind direction plates 15, B of each inclined portion 2a,
It is attached to the inner surface portion on the C side so as to cross the opening of the air outlet 6.

On the inner surface between the heater 4 and the outer peripheral portion of the fan, the second wind direction plate 16 is provided so as to extend from the end of each wind direction plate 15. More specifically, the second wind direction plate 16 is composed of two rectangular plate bodies having different lengths at the B and C (opposite to the rotation direction of the fan) sides and at the axial center of the hot air circulation fan 3. Inclined toward each other and arranged side by side. Of course, the second wind direction plates 16 and 16 are provided point-symmetrically with respect to the axial center portion of the hot air circulation fan 3, like the first wind direction plates 15. Then, by using the second wind direction plate 16 having a short inner overall length as the auxiliary wind direction plate 16a, a part of the wind directed to A and D is divided into the first and second wind direction plates 16a.
The wind direction plates 15 and 16 are used to catch and guide the air to the blower outlet 6 toward the fan reverse rotation direction.

The dimensions of each part shown in FIG. 1 are set to required values so that the wind guiding effect of the first and second air flow direction plates 15 and 16 can be satisfactorily obtained.

That is, the outer diameter a of the hot air circulation fan 3 is set within a range of approximately 1/2 to 1/3 of the lateral width b of the heating chamber 1. Specifically, when the width b is 300 mm (general width value), the outer diameter a is 150
It is set to ~ 100mm. In this embodiment, the outer diameter a is 130 mm.

The distance c between the second wind direction plate 16 and the hot air circulation fan 3 arranged outside is approximately 1 / outer diameter a of the hot air circulation fan 3.
It is set in the range of 10 to 1/20. Specifically, 13-6.
The distance c is 5 mm, and the distance c is 9 mm in this embodiment.

Further, the distance d between the second wind direction plate 16 and the inward auxiliary wind direction plate 16a is approximately 1/3 to 1/6 of the outer diameter a of the hot air circulation fan 3.
It is defined in the range of. Specifically, it is 43.3 to 21.7 mm, and the distance d is 33 mm in this embodiment. And
The distance d and the interval between the two first wind direction plates 15 and 15 are set to be substantially the same.

In addition, the distance e between the auxiliary airflow direction vane 16a and the hot air circulation fan 3 is set within a range of approximately 1/5 to 1/10 of the outer diameter a of the hot air circulation fan 3. Specifically, it will be 26 to 13 mm,
In this embodiment, the distance e is 19 mm.

In addition, the distance f between the auxiliary wind direction plate 16a, the wind direction plate 16 and the heater 4 is set within the range of approximately 1/2 to 1/10 of the outer diameter g of the heater 4. Specifically, when the outer diameter g is 7 mm (general heater diameter), the distance f is set to 3.5 to 0.7 mm. In this embodiment, the distance f is 1 mm.

Of course, each part on the C side is also set to have the same dimensions as the B side.

In addition, the width h of each of the outlets 6, 6 is set to be 2/3 or more (the width h ≧ 200 mm) of the width b of the heating chamber 1, and the hot air is blown to the left and right ends in the heating chamber 1. I'm trying to keep up. In addition, the horizontal width h is equally distributed to the left and right.

Then, when a large amount of food (not shown) is cooked at one time using the hot air circulation type microwave oven configured as described above, the shelves 10 on which the food (not shown) is placed are placed on the upper and lower shelves. Set them on the supports 11 and 11, respectively. Then,
After closing the door 9, the operation section (not shown) is operated. As a result, the fan motor 3a and the heater 4 are energized, and the central air in the heating chamber 1 is first sucked into the casing 2 from the suction port 5 by the hot air circulating fan 3 rotating leftward. Next, a counterclockwise air vortex is drawn and flows out to the inside of the casing 2, whereupon it is heated by the heater 4 and becomes hot air. Then, the hot air is blown from the outlets 6, 6 to the door 9 side using the inclined surfaces of the inclined portions 2a, 2a as guides. Then, as shown by the arrows in FIG. 3, each hot air is sucked into the suction port 5 above the upper shelf 10, below the lower shelf 10, and further between the intermediate shelves 10 and 10. The circulation of the hot air heats the food.

Here, during such cooking, the blowing direction of the hot air blown out from each of the outlets 6 tends to be biased by the counterclockwise vortex generated inside the casing 2 even if it is rectified by the punching holes. That is, as described above, the hot air from the lower outlet 6 is blown toward the right wall of the heating chamber 1, and the hot air from the upper outlet 6 is blown toward the left wall of the heating chamber 1. , A hot air flow tends to increase at points A and D.

However, the hot air that tends to flow toward the points A and D is guided to the points B and C by the first wind direction plate 15 and the second wind direction plate 16. That is, the amount of hot air blown out from points B and C of the outlets 6 and 6 increases due to the rectifying effect of the first wind direction plate 15 and the second wind direction plate 16, and accordingly, each A that causes uneven baking, The amount of hot air blown from point D decreases. In particular, the second wind direction plate
Since 16 is inclined with respect to the axial center of the hot air circulation fan 3 and is located up to the outer periphery of the fan, the hot air circulation fan 3
The rectifying effect by the second wind direction plate 16 comes to be exerted in the vicinity of, so that the amount of hot air blown out from the points B and C of the air outlets 6,6 can be increased more reliably, and Accordingly, the amount of hot air blown from points A and D can be reduced more reliably. As a result, it is understood that the unbalance of the hot air amounts on the left and right of the air outlets 6, 6 is corrected and a uniform hot air amount is sent into the heating chamber 1.

Therefore, unlike the conventional case, hot air is not strongly blown to the food locally, and uneven baking in the blowing direction can be effectively improved. In particular, when the dimensions a to g of the respective parts were set in the ranges described above, the left and right balance of the hot air amount could be most effectively and effectively balanced.

As a result of examining the dimensions of each part by experiments, in the hot-air circulation fan 3, when the outer diameter a exceeds approximately half the lateral width b of the heating chamber 1, the distance to the heater 4 decreases (distances c and e). Then, due to the overwhelmingness of the wind direction plates 15 and 16, a large heating unevenness appeared. Moreover, there is a problem that the air volume decreases as the outer diameter a increases. Further, when the outer diameter a was set to be smaller than the lateral width b was about 1/3, the air volume of the hot air circulation fan 3 decreased and the rising tendency tended to be slow.

In the distance c (between the second wind direction plate 16 and the hot air circulation fan 3), the distance c is approximately 1/10 of the outer diameter a of the hot air circulation fan 3.
When the temperature exceeds, the food color placed on the left side of the upper shelf 10 of the heating chamber 1 becomes darker in color (due to the weak action of the wind direction plates 15 and 16), and when the distance c becomes smaller than about 1/20, Upper shelf
10 The food on the left front is extremely light-colored (the food on the right is darker).

At the distance d (between the air flow direction plates 16 and 16a), when the distance d exceeds approximately 1/3 of the outer diameter a of the hot air circulation fan 3, the air flow direction plates 15 and 16 become too handy and hot air is blown to one place of the food. When the distance d is smaller than about 1/6, unevenness in heating occurs due to the concentration of the air flow, and even if there is a wind direction plate, it is in a state where it does not matter.

At the distance f (between the wind direction plates 16 and 16a and the heater 4), the distance f
When the diameter exceeds about 1/2 of the outer diameter g of the heater 4, hot air leaks.
If the foods on the A and B sides are darkened in color and are smaller than about 1/10, they may come into contact with the heater 4.

From these, it can be seen that the left-right balance of the hot air volume can be optimized by setting the dimensions within the above-mentioned range. However, the distance e defined in the range of approximately 1/5 to 1/10
The tendency (between the wind direction plate 16a and the hot air circulation fan 3) was substantially the same as the distance c.

In addition, although the second wind direction plate having a two-piece structure is used in one embodiment, there is no second inner wind direction plate that serves as an auxiliary wind direction plate.
A single wind vane may be used. In this case, the dimensional relationship such as the width of the heating chamber, the hot air circulation fan, the distance between the hot air circulation fan and the second wind direction plate, the distance between the second wind direction plate and the heater, and the first and From the balance of the size of the second wind direction plate, the mounting position, the mounting angle of the second wind direction plate with respect to the heater, and the like, the blowing characteristic that can effectively improve the uneven heating is determined.

[Effects of the Invention] As described above, according to the present invention, the amount of hot air from the fan reverse rotation direction side of the air outlet increases and the amount of hot air from the fan rotation direction side accordingly decreases, so that the air is blown out. The amount of hot air can be made uniform.

As a result, uneven heating can be improved. Moreover,
Since the second wind direction plate inclined toward the axial center of the centrifugal fan is provided, a large amount of hot air can be effectively guided to the fan reverse rotation side of the air outlet.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention.
The figure is a front view showing the structure around the wind direction plate of the hot air circulation type cooking device which is the main part, FIG. 2 is a front sectional view of the hot air circulation type cooking device, FIG. 3 is a side sectional view thereof, and FIG. FIG. 5 is a front sectional view showing the surroundings of the casing, FIG. 5 is a side sectional view showing a conventional hot air circulation type cooking device, FIG. 6 is a front sectional view thereof, and FIG. 7 is a front view showing the casing surroundings thereof. DESCRIPTION OF SYMBOLS 1 ... Heating chamber, 2 ... Casing, 2a ... Inclined part, 3 ... Hot air circulation fan (centrifugal fan), 3a ... Fan motor, 4 ... Heater, 5 ... Suction port, 6 ... Air outlet, 10 ... Shelf, 15 ... No. 1st wind direction plate, 16 ... 2nd wind direction plate, 16a ... Auxiliary wind direction plate.

Claims (6)

[Claims] 1. A heating chamber, a suction port provided at the center of one wall surface of the heating chamber, an outlet port provided in parallel at a position sandwiching the suction port on the same wall surface, and one of the heating chambers. A casing provided at the back of the wall surface for communicating the inlet and the outlet, a centrifugal fan provided in the casing so as to face the inlet, and a fan outer peripheral portion of the centrifugal fan in the casing and the centrifugal fan. A heater provided along with the air outlet and a portion of the inner surface of the casing facing the air outlet, which is provided at a portion opposite to the rotation of the centrifugal fan so as to cross the portion. No. 1 wind direction plate, and a second wind direction inclined toward the axial center portion of the centrifugal fan projecting from the inner surface portion of the casing between the heater and the fan outer peripheral portion in a continuous manner with the first wind direction plate. Heat characterized by having a plate Circulation type cooker. 2. The hot air circulation according to claim 1, wherein the outer diameter of the centrifugal fan is set in the range of approximately 1/2 to 1/3 with respect to the lateral width of the heating chamber. Cooker. 3. The distance between the second wind direction plate and the centrifugal fan is set within the range of about 1/10 to 1/20 of the outer diameter of the centrifugal fan. The hot-air circulating cooker according to the first item of the range. 4. The second wind direction plate has auxiliary wind direction plates arranged in parallel with each other at a distance of approximately 1/3 to 1/6 of the outer diameter of the centrifugal fan on the rotation direction side of the centrifugal fan. The hot-air circulation type cooking device according to claim 1, wherein 5. The distance between the auxiliary wind vane and the centrifugal fan is set within a range of approximately 1/5 to 1/10 of the outer diameter of the centrifugal fan. The hot air circulation type cooker according to the fourth aspect. 6. The distance between the second wind direction plate, the auxiliary wind direction plate and the heater is set within a range of about 1/2 to 1/10 of the outer diameter of the heater. Claim 4 to
The hot air circulation type cooker according to the item.