JPH062860A - Microwave oven with electric heater - Google Patents

Abstract

PURPOSE:To obtain a cooked result with less stickiness by providing an air guide device equipped with a shutter to regulate influent air into a heating compartment corresponding to cooking method and sort of food. CONSTITUTION:An air flow is generated by a cooling fan 4b with a driving motor 4a and guided into a heating compartment 1 by an air guide device. An openable shutter 10 with a driving motor is provided on the air guide device and can be held at any intermediate position between the full open and closed position. Therefore, the shutter 10 is held at an intermediate position during combination cooking in which a high-frequency oscillator 2 and an electric heater are energized simultaneously or alternately, and small portion of air generated by the cooling fan 4b with the driving motor 4a is introduced into the heating compartment 1 to expel steam and odor generated from food. Thereby, a delicious cooked result with less stickiness can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency heating device with an electric heating device, and more particularly to a shutter capable of opening and closing an opening to the heating chamber for controlling the air flowing into the heating chamber according to the cooking contents of food. The present invention relates to a high-frequency heating device with an electric heating device, which has an air guide device provided with.

[0002]

2. Description of the Related Art Conventionally, in a high-frequency heating device with an electric heating device, an air provided with a shutter capable of opening and closing an opening to the heating chamber in order to allow the air generated by a fan to flow into the heating chamber or to block the air. Many guide devices are in practical use.

That is, in the high-frequency cooking, the oven is opened to open the shutter in order to discharge the steam and the odor generated from the food, and the air generated by the cooling motor and the fan is introduced into the heating chamber to energize only the electric heating device. During cooking or grill cooking, or in combination cooking in which the high-frequency oscillator and the electric heating device are energized at the same time or alternately, the shutter is closed to prevent the air from the fan from flowing into the heating chamber. It is common to prevent temperature drop. Further, in a high-frequency heating device with an electric heating device that does not have a shutter that opens and closes, the number of rotations of the cooling motor is reduced by a means such as intermittent energization during cooking using the electric heating device to flow into the heating chamber. A means for controlling the air volume is also put to practical use.

Next, a conventional example of an air guide device having a shutter for opening and closing will be described.

First, a conventional example shown in FIG. 9 is one in which the shutter 32 is opened and closed by using a solenoid 31, and when the solenoid 31 is not energized, the shutter 32 is closed by a holding spring 33. The shutter 32 is moved by the coil spring 34 by energizing the solenoid 31 to open the opening of the heating chamber 35 to the intake port 36.

The method disclosed in Japanese Utility Model Laid-Open No. 58-188505 and Japanese Utility Model Laid-Open No. 63-46708 attempts to open and close the shutter by utilizing temperature deformation of bimetal or shape memory alloy.

Further, Japanese Utility Model Publication No. 62-160211,
The method disclosed in Japanese Utility Model Laid-Open No. 63-5302 is to use a motor that rotates only in one direction to operate a shutter only in an open / closed position through a linear cam groove.

[0008]

However, the conventional example has many problems as follows.

For the purpose of shortening the cooking time, a combination cooking in which the high frequency oscillator and the electric heating device are energized at the same time or alternately are energized has been put into practical use in recent years. A lot of water vapor is generated because it is heated by electromagnetic waves, but even if a shutter is provided, the shutter can be positioned only in the open position and the closed position, so the shutter is closed for cooking. Therefore, there are problems to be solved, such as the steam generated from the food is filled in the heating chamber and the food becomes sticky, or the door becomes cloudy and the cooking state of the food cannot be sufficiently grasped to obtain the desired finish. It was

Further, in the method in which the cooling motor is intermittently rotated to send a slight breeze into the heating chamber, the number of rotations of the cooling motor is reduced and the air volume for cooling the electric components and the outer shell is also reduced. If you try to maintain the performance, you will have to use parts with higher heat resistance, which will increase the cost, or the temperature will become too high to be dangerous to the user, and the cooling effect will decrease. Therefore, since the heating temperature by the electric heating device is set low, there is a problem that the food cannot be sufficiently cooked.

That is, when the method using the solenoid 31 shown in FIG. 9 or the bimetal or shape memory alloy found in Japanese Utility Model Laid-Open No. 58-188505 and Japanese Utility Model Laid-Open No. 63-46708 is used, the solenoid, the bimetal, Since the operation source of the shape memory alloy can only be ON and OFF, the shutter can be positioned only in the open position and the closed position, and the shutter cannot be held at the intermediate position between the open position and the closed position. There wasn't.

Further, in the methods of Japanese Utility Model Laid-Open No. 62-160211, and Japanese Utility Model Laid-Open No. 63-5302, a motor rotating only in one direction is used to open and close the shutter by a linear cam groove. However, the shutter is not held at the intermediate position. Even if the shutter is held at an arbitrary intermediate position between the open position and the closed position, many sensors for positioning are required, resulting in high cost and because the motor rotates only in one direction. There was a problem that the operation time of was long. FIG. 10 shows an operating state of the shutter 38 in the linear cam groove 37 into which the guide pin that is circularly moved by the rotation of the motor is inserted.

According to the present invention, steam, etc., in the heating chamber can be discharged to perform cooking with less stickiness, food can be sufficiently cooked, and the outside temperature can be kept low. A first object is to provide a high frequency heating device with an electric heating device.

A second object of the present invention is to provide a high-frequency heating device with an electric heating device, which can be expected to shorten the operation time of the shutter, is easy to position the shutter, and has a cost-effective construction. A third object is to provide a high-frequency heating device with an electric heating device that can open and close the shutter by detecting the humidity in the heating chamber with a sensor.

[0015]

In order to achieve the above first object, a high frequency heating apparatus with an electric heating device of the present invention includes an air guide device for guiding air generated by a cooling motor and a fan into a heating chamber to open and close. The shutter is operable and a motor for driving the shutter is provided, and the shutter can be held at any intermediate position between the open position and the closed position.

In order to achieve the second object, the high frequency heating device with an electric heating device of the present invention comprises an air guide device for guiding the air generated by a cooling motor and a fan into the heating chamber, and a shutter capable of opening and closing. A motor that rotates the shutter in both forward and reverse directions and a motor shaft that is attached to the motor shaft to transmit the motor rotation to the shutter via a cam groove formed on the shutter. A cam groove formed on the shutter, which is composed of a rotating plate equipped with a detecting means, has two arc portions corresponding to the open position and the closed position of the shutter, and an arbitrary intermediate position between the open position and the closed position of the shutter. A straight or curved portion for holding the shutter is formed outside the two arc portions, and the straight or curved portion is
The shutter can be held at the same intermediate position regardless of the rotation direction of the motor by energizing the motor for the same time from any detection point of the open position and the closed position of the shutter by the sensor.

In order to achieve the third object, the high-frequency heating device with an electric heating device of the present invention detects the humidity in the heating chamber with a humidity sensor depending on the selected cooking means, and when the humidity reaches a set level. The motor is energized to open and close the shutter.

[0018]

According to the high frequency heating apparatus with an electric heating device of the present invention, the shutter for opening / closing operation provided in the air guide device has an intermediate position between the open position and the closed position of the shutter. Since it can also be held at the position, when the high frequency oscillator and the electric heating device are energized at the same time, or when the combination is energized alternately, the shutter is held in the intermediate position and generated by the cooling motor and fan. Let the air flow slightly into the heating chamber,
The steam and odor generated by food can be discharged, and more delicious cooking with less stickiness can be performed. Further, even if the shutter is held at the intermediate position, most of the wind is applied to the electric components and the external cooling, which is advantageous in terms of durability, safety and cost of the components.

Further, with the structure for achieving the above second object, a motor capable of rotating in the forward and reverse directions is used for driving the shutter, and the cam groove formed on the shutter is opened and closed by the shutter. And two straight and curved portions that hold the shutter at an intermediate position are formed on the outer side of these two circular arc portions and the straight or curved portion of the shutter is in the open position or the closed position. Even from the detection point, regardless of the motor rotation direction, by energizing the motor for the same time and holding it in the same intermediate position, after detecting with the sensor whether it is the open position or the closed position of the shutter, By simply energizing the motor for a certain period of time, the shutter can be moved and positioned and held at another position, which is advantageous in terms of cost. That. Further, since the motor can rotate in both forward and reverse directions, the shutter operation time can be shortened and the cooking speed can be further improved.

Furthermore, a humidity sensor for detecting the humidity in the heating chamber is attached by the structure for achieving the third object, and when the detection level of the humidity sensor reaches a predetermined value, the control unit energizes the motor to operate the shutter. Due to the constitution, the food can be cooked quickly and deliciously. In combination cooking, the shutter is closed until the food is heated and a large amount of water vapor is generated, and the temperature in the heating chamber is not quickly lowered by the wind. When the level reaches a predetermined value, the shutter is opened to the middle position and the air is slightly flown into the heating chamber, so there is no problem that the door is clouded due to a sufficient amount of heat and the completion of cooking can not be grasped,
The desired cooking can be performed quickly and with less stickiness due to steam.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A high frequency heating apparatus with an electric heating device according to an embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) The main structure of the high frequency heating apparatus with an electric heating apparatus of Embodiment 1 will be described. 2 and 3
In (a), (b), and (c), a high-frequency oscillator 2 that oscillates a high-frequency electromagnetic wave is fixed to a heating-chamber side wall 1a that constitutes a heating chamber 1 of a high-frequency heating device with an electric heating device, and a heating chamber upper plate. An electric heating device 3 is attached near 1b. Further, a cooling motor 4a and a fan 4b for cooling electric parts such as the high frequency oscillator 2 and the outer cover 17 and for sending air into the heating chamber 1 are attached to the heating chamber side wall 1a, and the air is heated in the heating chamber. An air guide device 5 for guiding inside 1 is fixed.

Next, the operation of the air guide device of this embodiment will be described. When cooking with only high-frequency electromagnetic waves by the high-frequency heating device with an electric heating device, the shutter 10 constituting the air guide device 5 as shown in FIG.
Is opened, and the wind generated by the rotation of the cooling motor 4a and the fan 4b passes through the high frequency oscillator 2 and is guided by the air guide device 5 into the heating chamber 1 through the intake port 1c formed in the heating chamber side wall 1a. Water vapor and odors generated by heating the food 6 are discharged to the outside of the heating chamber through the exhaust port 1d formed in the heating chamber side wall 1a. Figure 3 shows the flow of wind at this time.
(A) Indicated by a middle arrow.

In the case of oven cooking or grill cooking in which the food 6 is heated and cooked by using only the electric heating device 3, FIG.
As shown in (b), the shutter 10 is closed to prevent air from flowing into the heating chamber 1. Therefore,
The food 6 in the heating chamber 1 is quickly heated, and all the wind generated by the cooling motor 4a and the fan 4b is spent for cooling the electric parts and the outer cover 17, thereby suppressing the temperature rise. The motor 4c and the fan 4d are used to stir the air in the heating chamber 1 when cooking using only the electric heating device 3. Further, in the combination cooking in which the high frequency oscillator 2 and the electric heating device 3 are energized at the same time or alternately, the food 6 is heated from the inside, so that the generation of steam increases. Therefore, in this embodiment, when the combination cooking is selected, the shutter 10 is held at the intermediate position as shown in FIG. 3C, and the air is slightly flown into the heating chamber 1 to heat the food 6. The generated steam is discharged to the outside of the heating chamber through the exhaust port 1d. Therefore,
Even in the combination cooking, there is no problem that the inner surface of the door 15 becomes cloudy and the cooking status of the food 6 cannot be sufficiently grasped, and delicious cooking with less stickiness due to steam can be performed. Further, at this time, most of the wind generated by the cooling motor 4a and the fan 4b is spent for cooling the electric parts and the outer cover 17, so that the method of limiting the rotation of the cooling motor of the conventional example has been found. Problems such as cooking performance, danger and durability can be solved.

(Embodiment 2) Next, the structure and operation of the air guide device 5 of Embodiment 2 will be described with reference to FIGS. 1, 4 and 5.

The air guide device 5 is composed of a side surface 7a and a top surface 7b which are opposed to each other and have a motor 8 fixed to the outer side and a sensor 12 composed of a limit switch with the motor shaft 8a protruding to the inner side. Top surface 7 of side surface 7a
The base portion 7d of the side surface 7a having a pair of ears having a small hole 7c on the b side and a U-shaped cross section is provided on the side wall 1 of the heating chamber 1 near the intake port 1c.
a, the air guide body 7 fixed to the motor shaft 8a, the protrusion 9b on the outer periphery fixed to the motor shaft 8a, the rotary plate 9 in which the guide pin 9a is vertically projected on the surface opposite to the motor 8 side, and the rotary plate 9 A pair of ears having vertical surfaces 10b perpendicular to the vertical surface 10b, and small holes 10c formed by bending both ends of one side of the vertical surface 10b at a right angle, and a part of one side of the vertical surface 10b on the rotating plate 9 side is bent at a right angle. Inside the air guide main body 7 having a shutter 10 having a horizontal surface 10a having a cam groove 11 into which the guide pin 9a is inserted and an opening 13a opened and closed by the shutter 10, the opening 13a faces the intake port 1c. A partition plate 13 having an L-shaped cross section fixed to the air guide body 7 is provided, and the small holes 7c of the pair of ears of the air guide body 7 and the small holes 10c of the pair of ears of the shutter 10 are brought into contact with each other. Hole 7c, 1 c shutter 10 by inserting the shaft 14 is rotatably held in the projections 9b of the rotary plate 9 is brought into contact with the protruding portion 12a of the limit switch shutter 1
The position detecting means of 0 is provided.

In the present embodiment, as the position detecting means of the shutter 10, the convex switch 9b of the rotary plate 9 is aligned with the projecting part 12a of the limit switch at the open position of the shutter 10, and the limit switch is used as the sensor 12. It goes without saying that the position of the shutter 10 may be detected by means (for example, a hole is provided in the rotary plate and detection is performed by an optical sensor). In this embodiment, since the sensor 12 detects the open position of the shutter 10, the cam groove 11 corresponding to the open position of the shutter 10 has a circular arc 11a centered on the sensor detection point 1 and rotates. The cam groove 11 corresponding to the closed position of the shutter 10 corresponding to the position where the plate 9 is half-turned from the detection point 1 is an arc 11b. Further, linear portions 11c and 11d are formed on both sides of the two arc portions 11a and 11b. In the present embodiment, the straight line portions 11c and 11d are formed by straight lines, but the same effect can be obtained by using curved lines. Further, the linear portions 11c and 11d of the cam groove 11 are shaped so that they can be held at the same intermediate position Z even if the motor is rotated in the forward direction and the reverse direction for the same time from the detection point l.

After the convex portion 9b formed on the rotary plate 9 detects that the shutter 10 is in the open position X by the sensor (limit switch) 12, the control unit 16 can perform oven cooking, grill cooking or combination cooking. When selected, the motor 8 is energized for a predetermined time and the shutter 10 is moved to the closed position Y or the intermediate position Z. When the motor 8 is energized, the rotary plate 9 attached to the motor shaft 8a also starts to rotate. When the guide pin 9a fixed to the surface of the rotary plate 9 is located in the arc portion 11a of the cam groove 11, the guide pin 9a only slides in the cam groove 11 and does not rotate the shutter 10. Further, when the motor 8 is energized and the rotary plate 9 rotates, the guide pin 9a also moves. And
If the guide pin 9a moves to the point n1 or n2, the shutter 10 is rotated to the intermediate position Z.
If the control unit 16 selects cooking for holding the shutter 10 at the intermediate position Z, the motor 8 is set at T2 from the detection point l.
The shutter 10 is held at the intermediate position Z only by being energized for a time. In addition, the control unit 16 uses the shutter 1
If the cooking to close 0 is selected, the motor 8 is further energized by the signal from the control unit 16, the rotating plate 9 also continues to rotate, the guide pin 9a also continues to move in the cam groove 11, and the shutter is released. Rotate 10 When the rotary plate 9 further rotates and the guide pin 9a reaches the arc portion 11b of the cam groove 11, the shutter 10 has moved to the closed position. When the guide pin 9a is on the arc portion 11b, the guide pin 9a on the rotary plate 9 only slides in the cam groove 11 and does not apply any rotational force to the shutter 10. T from detection point l
When one hour has passed, the power supply to the motor 8 is stopped and the shutter 10 is held at the closed position Y. When the shutter 10 is moved from the closed position Y or the intermediate position Z to the open position X, the motor 8 is energized until the sensor (limit switch) 12 detects the convex portion 9b formed on the outer periphery of the rotating plate 9. Further, in this embodiment, the motor 8 that can rotate in the forward and reverse directions is used, and the straight portions 11c and 11d of the cam groove 11 are energized from the detection point 1 to the motor 8 for the same time regardless of the rotation direction of the motor 8. Even if the shutter 10 is held in the same intermediate position Z, the operating time of the shutter 10 can be shortened and the heating temperature can be raised more quickly. That is, when the motor 8 rotates only in one direction, the shutter 10 is moved to the intermediate position Z.
When trying to move the rotary plate 9 to the open position X from the
Although only rotation movement from 1 → m → n2 → l point is possible, in the present embodiment, rotation to n1 → l point is also possible, and it can be expected to shorten the shutter operation time.

(Embodiment 3) Next, a configuration for opening and closing a shutter by a signal from a humidity sensor and its operation will be described. In the third embodiment, as shown in FIG. 2, a humidity sensor 18 is installed in the heating chamber 1, and when the combination cooking is selected by the control unit 16, the shutter 10 is kept open until the food 6 is heated and steam is generated. Close and cook quickly, and use steam generated from food 6 to heat cooking chamber 1
When the humidity sensor 18 detects that the humidity level has reached a certain humidity level, the control unit 16 outputs a signal for rotating the motor 8 to move the shutter 10 to the intermediate position Z. As a result, the wind slightly flows into the heating chamber 1, and the steam in the heating chamber 1 can be discharged. According to this example, delicious cooking with less stickiness was made possible without prolonging the cooking time.

[0030]

As is clear from the above description of the embodiments, according to the high frequency heating apparatus with an electric heating device of the present invention, many effects can be expected as follows.

(1) Since the shutter constituting the air guide device is held not only in the open position and the closed position but also in the intermediate position between the open position and the closed position, the shutter can be placed in the heating chamber even when cooking the combination. A small amount of wind can be introduced, and the steam generated by the food can be discharged to the outside of the heating chamber for delicious cooking with less stickiness.

(2) Even if the shutter is held at the intermediate position, the rotation of the cooling motor is not reduced, and most of the wind acts on the cooling of the electric parts and the outside.
Not only can the food be sufficiently cooked, but it is also advantageous in terms of durability, safety, and cost.

(3) A motor capable of rotating in the forward direction and the reverse direction is used, and the straight or curved portion of the cam groove is irrespective of the rotation direction of the motor regardless of whether the shutter is open or closed. By having a shape that can be energized for the same time and held at the same intermediate position, the shutter operation time can be expected to be shortened and a high-frequency heating device with an electric heating device having better heating characteristics can be obtained.

(4) Since the humidity sensor detects the water vapor level in the heating chamber to open and close the shutter, the desired cooking can be performed efficiently and while sufficiently grasping the cooking state.

[Brief description of drawings]

FIG. 1 is a side view of a shutter of an air guide device showing a state in which a shutter is held in an open position, an intermediate position, and a closed position in a high frequency with an electric heating device of an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the high-frequency heating device with the electric heating device.

FIG. 3 (a) is a horizontal cross-sectional view of a high-frequency heating device with an electric heating device showing the flow of air in the heating chamber at the shutter open position. (B) High-frequency with an electric heating device showing the flow of air in the heating chamber at the shutter closed position. Horizontal cross-sectional view of the heating device (c) Horizontal cross-sectional view of the high-frequency heating device with an electric heating device showing the wind flow in the heating chamber at the shutter intermediate position

FIG. 4 is an exploded perspective view showing constituent parts of the air guide device.

FIG. 5 is a plan view of the air guide device.

FIG. 6 is a time chart when the same humidity sensor is used.

[Figure 7] Circuit diagram

FIG. 8 is a perspective view showing the same appearance.

FIG. 9 is a side view showing an opened / closed state of a shutter operated by a solenoid of a conventional high-frequency heating device with an electric heating device.

FIG. 10 is a side view showing an opened / closed state of the shutter operated by a guide pin driven by rotation of a motor inserted in a cam groove of the shutter.

[Explanation of symbols]

 1 heating chamber 1c intake port 1d exhaust port 2 high frequency oscillator 3 electric heating device 4a cooling motor 4b fan 5 air guide device 6 food 8 motor 8a motor shaft 9 rotating plate 9a guide pin 10 shutter 11 cam groove 11a, 11b arc portion 11c, 11d Linear part 12 Sensor 16 Control part 18 Humidity sensor X Open position Y Closed position Z Intermediate position l Detection point

Claims (4)

[Claims] 1. A heating chamber having an intake port and an exhaust port for containing and cooking food, a high frequency oscillator for oscillating high frequency electromagnetic waves, an electric heating device for heating the food, and selection of cooking means. A control unit for transmitting and receiving an electric signal, a cooling motor and a fan for cooling the electric parts and blowing air into the heating chamber, and an air guide device for guiding the air generated by the cooling motor and the fan, The air guide device includes a shutter capable of opening and closing an opening to the heating chamber and a motor for driving the shutter, and the shutter is placed at an open position, a closed position, and an arbitrary intermediate position between the open position and the closed position. A high-frequency heating device with an electric heating device, which is also capable of holding. 2. A heating chamber having an intake port and an exhaust port for containing and cooking food, a high frequency oscillator for oscillating high frequency electromagnetic waves, an electric heating device for heating the food, and selection of cooking means. A control unit for transmitting and receiving an electric signal, a cooling motor and a fan for cooling the electric parts and blowing air into the heating chamber, and an air guide device for guiding the air generated by the cooling motor and the fan, The air guide device includes a shutter capable of opening and closing the opening to the heating chamber, a motor for driving the shutter, which is rotatable in forward and reverse directions, and a guide pin fixed to a motor shaft of the motor. A cam groove having a plate, into which the guide pin formed on the horizontal surface of the shutter is inserted, two arc portions corresponding to the open position and the closed position of the shutter, An open position of the shutter, a straight line or a curved portion for holding the shutter at an arbitrary intermediate position between the closed positions is formed outside the two arc portions, and the straight or curved portion is an open position of the shutter by a sensor, A high-frequency heating device with an electric heating device having a configuration in which the shutter can be held at the same intermediate position regardless of the rotation direction of the motor by energizing the motor for the same time from any detection point of the closed position. 3. A motor is fixed to the outside, and a sensor consisting of a limit switch, which protrudes the motor shaft of the motor, is fixed to one side. An air guide body having a U-shaped cross section having a pair of ears provided with a small hole, and a base portion of the side surface fixed to a heating chamber side wall in the vicinity of the intake port; and a protrusion on the outer periphery fixed to the motor shaft, A rotating plate with a guide pin protruding vertically on the surface opposite to the motor side, a vertical surface perpendicular to the rotating plate, and a pair of ears having small holes formed by bending both ends of one side of the vertical surface at a right angle. A shutter having a horizontal surface provided with a cam groove into which the guide pin is formed by bending a part of one side of the vertical surface on the rotating plate side at a right angle; and the air guide having an opening opened and closed by the shutter. Inside the body A partition plate having an L-shaped cross section fixed so that the opening portion faces the intake port is provided, and the small hole of the ear portion of the air guide body and the small hole of the ear portion of the shutter are brought into contact with each other. An air guide having a structure in which the shutter is rotatably held by inserting a shaft into each of the small holes, and the projection of the rotary plate is brought into contact with the projection of the limit switch to serve as shutter position detection means. The high frequency heating device with an electric heating device according to claim 2, further comprising a device. 4. A heating chamber having an intake port and an exhaust port for containing and cooking food, a high-frequency oscillator for oscillating high-frequency electromagnetic waves, an electric heating device for heating the food, and selection of cooking means. A control unit for transmitting and receiving an electric signal, a cooling motor and a fan for cooling the electric parts and blowing air into the heating chamber, and an air guide device for guiding the air generated by the cooling motor and the fan, The air guide device includes a shutter capable of opening and closing the opening to the heating chamber and a motor for driving the shutter, and depending on cooking means, the shutter is opened and closed by a signal from a humidity sensor. Heating device.