JPH089542Y2 - Microwave with range hood - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a microwave oven with a range hood.

<Prior Art> FIG. 6 is a view for explaining the configuration of a conventional microwave oven with a range hood, in which (a) is a front view, (b) is a plan view excluding a cabinet top plate, c) is a front view without a door, (d) is a side view without cabinet side plates, (e) is a side view without an intake duct in (d), and FIG. 7 is an explanatory view of a steam duct. , (A) is a side sectional view, and (b) is a schematic perspective view.

Microwave oven with range hood (hereinafter referred to as microwave oven)
10 is a heating chamber 20 in a cabinet 11 that has a substantially rectangular parallelepiped appearance.
And a power supply unit 30, and the heating chamber 20 is provided in front of the heating chamber.
A door 12 with a window for opening and closing 20 is provided, and an operation unit 13 for selecting a cooking course is provided at the front of the power supply unit 30 (Fig. 6 (a)).

The power supply unit 30 is provided with a magnetron 31, a high-voltage transformer 32, a cooling fan 51 arranged between the high-voltage transformer 32 and the front of the cabinet, and electric parts such as a condenser (not shown).

The heating chamber 20 is adjacent to the power supply unit 30 and has an inner wall made of a metal plate. A partition wall 21 is formed between the heating chamber 20 and the power supply unit 30 by sandwiching a heat insulating material (not shown) between the metal plate and a heat shield plate (not shown) forming an inner wall of the power supply unit 30. Is provided. The partition wall 21 is provided with a large number of punching holes and a damper 22 for opening and closing the punching holes. Further, the heating chamber 20 is provided with a heater unit 23 on the side opposite to the power supply section 30. An intake port 14 is provided at the bottom of the front of the cabinet 11, and a hood louver 15 is provided at the upper front, top, or back of the cabinet 11. The exhaust air from the hood louver 15 is connected to the exhaust duct already installed in the house or is exhausted indoors.

The ventilation passage of the microwave oven 10 is composed of two passages, a ventilation passage for the range hood and a ventilation passage for cooling the components. The ventilation passage for the range hood is the range hood intake ducts 41 and 42,
It is provided with a hood fan 43, a range hood exhaust duct 44, and a charcoal filter 45.

It goes through the range hood intake ducts 41 and 42 arranged on the left and right in the cabinet 11, and reaches the hood fan 43 provided at the rear part on the top plate 20a of the heating chamber 20. And food fans
The air is exhausted in any direction such as forward, upward, and backward by 43.

FIG. 6D shows a case where the cooling air A passing through the hood fan 43 is guided to the range hood exhaust duct 44, passes through the charcoal filter 45, and is exhausted forward through the hood louver 15. There is.

On the other hand, the component cooling air passage includes a cooling fan 51, a magnetron exhaust duct 52, and a magnetron exhaust guide 53. The cooling air B drawn from the right end of the hood louver 15 shown in the figure passes through a cooling fan 51 provided at the bottom of the cabinet 11 to cool the high-voltage transformer 32, the magnetron 31, etc., as shown in FIG. 6 (e). To do. And cooling air B
Is guided to the magnetron exhaust guide 53 through the magnetron exhaust duct 52 and exhausted forward through the hood louver 15. The cooling air C separated from the cooling air B (6th
As shown in FIG. 6C, the gas flows into the heating chamber 20 through the punching holes which are not closed by the damper 22. Further, the microwave oven 10 is provided with a steam duct 61 as a discharge path for the warm air D such as steam generated from the object to be heated such as food. The steam duct 61 is adjacent to the front magnetron exhaust duct 52 in front of the heating chamber 20 on the top plate, and one end of the steam duct 61 communicates with the heating chamber 20 through the heating chamber exhaust port 24 provided on the heating chamber top plate 20a. are doing. The other end of the steam duct 61 is connected to the hood louver 15 from the front surface of the cabinet 11 (see FIG. 7 (a)).

During microwave cooking of the microwave oven, that is, during microwave oscillation, the damper 22 is opened and the cooling air C flows into the heating chamber 20 through the punching holes. The warm air D such as steam generated inside the heating chamber 20 passes through the steam duct 61 and is discharged from the hood louver 15 to the outside.

Also, during convection cooking, that is, when the heater unit 22 is energized and hot air is circulated in the room, the damper is
22 is closed so that the cooling air C does not flow into the heating chamber 20.

<Problems to be Solved by the Invention> However, the above-described ventilation passage has the following problems.

During convection cooking, the hot air D, which is a considerably high temperature steam due to natural convection in the heating chamber 20, passes through the steam duct 61 and reaches the hood louver 15, so that the temperature of the hood louver 15 also rises. However, the hood louver 15 is a molded product of synthetic resin, and even if a heat-resistant resin is used, it may melt or deform depending on the temperature of the warm air D. Further, during micro cooking, the damper 22 is opened and the cooling air C flows into the heating chamber 20, and the warm air D is discharged. However, when the timer is set for a long time by mistake and the object to be heated begins to burn, the flame may pass through the steam duct 61 and go out from the hood louver 15 to the outside.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a microwave oven with a range hood in which the temperature rise of the hood louver is reduced and the flame is not emitted to the outside.

<Means for Solving the Problems> A microwave oven with a range hood according to the present invention includes a hood louver provided at an upper part of a cabinet, a heating chamber having a heater unit housed in the cabinet, and a partition wall of the heating chamber. Adjacent to the heating chamber via a power supply unit having a magnetron and a high-voltage transformer, a cooling fan for cooling the power supply unit, a magnetron exhaust duct for guiding the cooling air cooling the power supply unit to the hood louver, and a heating unit. A steam duct is provided on the ceiling plate of the room and guides hot air in the heating room to the hood louver. Further, the magnetron exhaust duct is formed with a notch and an opening that communicate with the steam duct, and the steam duct has a first straightening vane that divides the warm air that has flowed in through the opening into two directions and a heating chamber. A second straightening vane that guides the hot air rising through the steam duct to the hood louver in a labyrinth, is provided between the second straightening vane and the hood louver, and the steam duct and the hood are provided based on the temperature of the hot air. A shutter for opening and closing the louver is provided.

<Operation> The magnetron cooling air passing through the magnetron exhaust duct is divided into three parts by the notch and the opening.

 A part of it flows out from the hood louver.

Some others enter the steam duct through the notches. Then, it flows along the hood louver and flows out from the hood louver while cooling it.

Also, the rest flows into the steam duct through the opening,
It is further divided into two by the first straightening vane.

Then, a part of the air flows from the side opposite to the cutout through the space between the first straightening vanes and flows out to the outside while cooling the hood louver on the side opposite to the cutout.

The remaining part flows into the steam duct and is ejected from the heating chamber to the steam duct, forming hot air and pushing in the temperature that rises due to natural convection.

Further, the second rectifying plate guides the warm air generated from the heating chamber in a labyrinth. The hot air that has passed through the second baffle plate does not flow out by the shutter that closes the steam duct when the temperature becomes equal to or higher than the set value.

<Embodiment> An embodiment according to the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic external perspective view of a magnetron exhaust duct and a steam duct, FIG. 2 is a configuration explanatory view of the steam duct, (a) is a side sectional view, (b) is a front view, and FIG. 3 is a schematic view. In the external perspective view, (a) shows a steam duct,
(B) shows the 1st current plate, (c) has shown the 2nd current plate, respectively. FIG. 4 is a sectional explanatory view showing a structure of the shutter, and FIG. 5 is a sectional explanatory view showing a closed state of the shutter. In the following description, the same parts as those in the prior art are designated by the same reference numerals.

The main structure of the microwave oven 10 of the present invention is a cabinet 11
It has a heating chamber 20 and a power supply unit 30 adjacent to the heating chamber 20. The power supply unit 30 is provided with a magnetron 31, a high voltage transformer 32, and electric parts such as a capacitor.

The heating chamber 20 is provided with a partition wall 21, a damper 22 and a heater unit 23 having the same structure as the conventional one shown in FIG. 6 (c). Further, the ventilation passage for the range hood of the microwave oven 10 of the present invention includes the range hood intake ducts 41 and 42, the hood fan 43, the range hood exhaust duct 44, and the charcoal filter 45 as in the conventional case. Further, the component cooling air passage includes a cooling fan 51, a magnetron exhaust duct 52, and a magnetron exhaust guide 53.

The microwave oven 10 of the present invention is different from the conventional one in the steam duct 61. That is, the conventional steam duct has the notch 62, the opening 63, the first straightening vane 64, and the second straightening vane 65.

The cutout 62 is formed by cutting out one side surface of the front end portion of the magnetron exhaust guide 53 over a portion indicated by a broken line in FIG. Further, the opening 63 is formed at the upper end of the steam duct 61 along with the cutout 62. All of them are connected to the magnetron exhaust duct 52 so that the cooling air B can flow in.

The first straightening vane 64 has a vertical wall as shown in FIG. 3 (b).
It has a vertical wall 64a and an inclined wall 64b bent in the longitudinal direction at an acute angle. The vertical wall 64a is connected to the ceiling surface of the steam duct 61, and is arranged so as to divide the cooling air B flowing from the opening 63 into two (see FIG. 2 (a)).

As shown in FIG. 3 (c), the second rectifying plate 65 has a vertical wall 65a and an inclined wall 65b which conform to the above description.
And the vertical walls 64a and 65a of the second straightening vanes 64 and 65 are also inclined walls.
64b and 65b are arranged in the steam duct 61 so as to be substantially parallel to each other (see FIG. 2 (a)).

The shutter 66 is a lid-shaped plate that opens and closes the steam duct 61, and is provided between the second rectifying plate 65 and the hood louver 15. As shown in FIG. 4, the upper end of the shutter 66 is rotatably suspended at a fulcrum 61a provided on the ceiling of the steam duct 61. Further, the lower end thereof is attached to the side wall 61b of the vertical portion of the steam duct 61 via a shape memory alloy 67 formed in a coil shape, for example. And the shutter 66 is always pulled by the shape memory alloy 67, and the steam duct
61 is open and communicates with the hood louver 15. Further, when the temperature of the shape memory alloy 67 rises and exceeds the transition point, the shape memory alloy 67 extends and the shutter 66 hangs down, its lower end abuts the inner edge 11a of the cabinet 11, the steam duct 61 is closed, and the hood is closed. The louver 15 is blocked.

Next, the ventilation operation of the microwave oven of the present invention will be described in more detail.

(B) In the case of micro cooking Cooling air B sucked from the hood louver 15 to cool the magnetron 31 along the ventilation passage for cooling the components passes through the magnetron exhaust duct 52 (see FIG. 1) and hits the hood louver 15. . However, since the temperature of the cooling air B is 90 ° C. or lower, it does not affect the resin material.

Cooling air C flowing into the heating chamber 20 through punching holes
Becomes hot air D containing water vapor and the like and flows into the steam duct 61 from the heating chamber exhaust port 24. However, since the temperature of the warm air D is relatively low, the shape memory alloy 67 does not reach the temperature exceeding the transition point, and has the initially memorized shape as shown in FIG. Therefore, the shutter 66 remains open.
Then, the warm air D is discharged from the hood louver 15.

(B) During convection cooking Since the magnetron 31 is not energized, the cooling air B having a relatively low temperature flows out from the magnetron exhaust duct 52. Part of this cooling air B is the magnetron exhaust guide.
Steam duct 61 is provided as a cooling air flow E through a notch 62 provided in 53 and as a cooling air flow F through an opening 63, respectively.
Flows into. The cooling air B other than the cooling air E and the cooling air F is discharged from the hood louver 15 to the outside as it is.

Cooling wind E flowing into the steam duct 61 from the notch 62
Flows along the hood louver 15 as it is, and cools the hood louver 15. However, the cooling air E does not reach the opposite side (left side in the drawing) of the notch 62 of the hood louver 15 sufficiently.

On the other hand, the cooling wind F flowing into the steam duct 61 from the opening 63 is further branched into two cooling winds G and H. The cooling air G passes between the vertical wall 64a and the bent wall 64b of the first straightening vane 64, and flows out from the tip end blowing portion 64c (the left side in FIG. 2B) of the first straightening vane 64. Cool the hood louver 15 from the left side. With this cooling air G and the cooling air E, the hood louver
15 will be cooled from both ends.

As shown in FIG. 2 (b), the cooling air H branched in the preceding paragraph flows into the steam duct 61 without passing between the vertical wall 64 a and the bent wall 64 b of the straightening vane 64.

The warm air D heated by the heater unit 23 in the heating chamber 20 becomes hot air by natural convection, rises from the exhaust port 24 of the top plate 20a of the heating chamber 20, and flows into the steam duct 61. However, the cooling air H of the preceding paragraph acts so as to push in the warm air D that is going to rise (see FIG. 2 (b)). Further, since the ventilation path for the warm air D is formed in a labyrinth shape by the second straightening plate 65, the temperature D of the heating chamber 20 is less likely to be released.

When the hot air D flowing into the steam duct 61 reaches a high temperature and exceeds the transition point of the shape memory alloy 67, the shape memory alloy 67 extends and the shutter 66 hangs down, as shown in FIG.
Close the steam duct 61. Therefore, since the warm air D is not discharged to the outside, the hood louver 15 is not deformed by the hot air.

When the temperature of the warm air D falls below the transition point, shape memory alloy
67 returns to its original shape and steam duct 61 opens.

(C) In the case of food ignition Since the same as (b) above applies, the description is omitted.

In each of the above items, the cooling air A passing through the ventilation passage for the range hood is the same as the conventional one. With the above-mentioned configuration, the temperature of the hood louver 15 which was conventionally about 180 ° C can be lowered to about 120 ° C.

In the above embodiment, the shape memory alloy is used as the temperature detection actuating means, but it is not limited to this and may be the one shown in FIG. 5, for example. That is, the thermistor 68 may be provided in the steam duct 61 near the heating chamber discharge port 24, and the shutter 66 may be opened and closed by a motor (not shown) that rotates a certain angle based on the temperature detection signal of the thermistor. .

<Effects of the Invention> As described above, in the microwave oven with a range hood according to the present invention, the magnetron is cooled and the cooling air exhausted from the magnetron exhaust duct is branched into three directions. That is, a part of the cooling air is guided to the steam duct and the other part is directly guided to the hood louver, and the cooling air guided to the steam duct is divided into two directions by the first straightening vane.

First, the cooling air directly guided to the hood louver cools the hood louver from the magnetron exhaust duct side. In addition, the cooling air that has flowed into the first straightening vane in the steam duct through the opening provided in the magnetron exhaust guide, that is, the cooling air separated by the first straightening vane, has an opening formed by the first straightening vane. The hood louver is guided to the side opposite to the side where it is provided and cools the hood louver from the side opposite to the side where the magnetron exhaust duct is provided. Further, the cooling air that has flowed into the steam duct through the notch provided in the magnetron exhaust guide cools the entire hood louver.

That is, as described above, since the hood louver is cooled from three directions, the hood louver can be made of a low-cost resin that does not have high heat resistance, so that the cost of the microwave oven with a range hood can be reduced. Contribute to.

On the other hand, when the heating chamber is heated by convection cooking, hot air from the heating chamber flows into the steam duct through the exhaust port. Here, since the second straightening vane is formed in a labyrinth, the temperature drops to some extent before reaching the hood louver. Therefore, the hood louver can be made of low-cost resin.

In addition, the hot air from the heating chamber has a predetermined temperature or higher, for example,
If the temperature does not drop even if it is guided in a labyrinth by the baffle plate of, or if the food in the heating chamber ignites and hot air is accompanied by flames, the shutter operates and the hood Since the louver and the steam duct are closed, hot air does not blow out from the hood louver.
Therefore, the hood louver can be made of a low-cost resin, and even if the food in the heating chamber ignites, the hood louver does not emit a flame, which is very safe.

[Brief description of drawings]

1 to 5 are drawings relating to the present invention, and FIG. 1 is a schematic external perspective view of a magnetron exhaust duct and a steam duct,
FIG. 2 is a configuration explanatory view of a steam duct, (a) is a side sectional view, (b) is a front view, FIG. 3 is a schematic external perspective view, (a) shows a steam duct, and (b) shows The first rectifying plate and the second rectifying plate are shown in (c). Fourth
FIG. 5 is a sectional explanatory view showing the structure of the shutter, and FIG. 5 is a sectional explanatory view showing the closed state of the shutter. FIG. 6 is a drawing for explaining the structure of a conventional microwave oven with a range hood, in which (a) is a front view, (b) is a plan view excluding the top plate of the cabinet, and (c) is a door. The removed front view, (d) is a side view without the side plate of the cabinet, (e) is a side view without the intake duct of (d), FIG. 7 is an explanatory view of the steam duct, and (a) is A side sectional view, (b) is a schematic perspective view. 10 …… Microwave oven of the present invention 14 …… Intake port 15 …… Hood louver 20 …… Heating chamber 22 …… Damper 23 …… Heater unit 24 …… Heating chamber exhaust port 30 …… Power supply section 31 …… Magnetron 43… … Hood fan 51 …… Cooling fan 52 …… Magnetron exhaust duct 53 …… Magnetron exhaust guide 61 …… Steam duct 62 …… Notch 63 …… Opening 64 …… First straightening plate 65 …… Second straightening plate 66 ……Shutter

Claims (1)

[Scope of utility model registration request] 1. A hood louver provided in the upper part of a cabinet, a heating chamber having a heater unit housed in the cabinet, and a heating chamber having a partition wall adjacent to the heating chamber, a magnetron and a high-voltage transformer. A power supply unit having a cooling fan that cools the power supply unit, a magnetron exhaust duct that guides the cooling air that has cooled the power supply unit to the hood louver, and a ceiling plate of the heating chamber. The magnetron exhaust duct is formed with a notch and an opening communicating with the steam duct, and the steam duct flowing in the steam duct in two directions. First to divide
Baffle plate and a second baffle plate that guides the hot air rising from the heating chamber through the steam duct to the hood louver in a labyrinth.
A microwave oven with a range hood, which is provided between the second rectifying plate and the hood louver, and is provided with a shutter which opens and closes between the steam duct and the hood louver based on the temperature of the hot air.