JPH02293528A - Automatic heating device - Google Patents

Abstract

PURPOSE:To prevent an over-heating of a heated item by a method wherein a cold air mixing and discharging passage is provided, an aeration air discharging speed is made fast, a gas pressure is partially reduced and the evacuated air in the gas passage connected to the heating chamber is sucked out. CONSTITUTION:A varying part 4 acting as a part varying a sectional area arranged in the midway of a gas passage 2 is provided with a cold air mixing and discharging passage 25 for use in mixing and discharging the cold air from an air blower 8 so as to make an air speed within the passage 25 fast to decrease an air pressure and an aeration port of the gas passage 2 connected to the heating chamber 1 is arranged at a position where the gas pressure is reduced. In simultaneous with an application of air pressure to the heating chamber 1 through an air blowing of the air pressure to the heating chamber 1 through an air blowing of the air blower 8 during heating of the heated item 13, an aeration air speed in the cold air mixing and discharging passage 25 is made fast, the gas pressure is locally reduced, the pressure may suck up the discharged air from the heating chamber 1. A variation in state of hot gas of the water vapor gas from the heated item 13 is rapidly transmitted to a heat receiving surface 28 of the pyroelectric sensor 3, the heated condition of the heated item 13 is detected and so the heated item 13 is not over-heated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention detects hot air contained in steam and gas emitted according to the heating state of the object to appropriately determine the heating end time of the object to be heated. It is related to an automatic heating device that achieves good heating conditions. Conventional technology Conventionally, automatic heating devices require detection means to detect the heating state of the food to be heated, and this means uses exhaust gas to exhaust air from the heating chamber to the outside of the machine. A sensor is placed as a detection means in the middle of the passage, and by detecting the generation and concentration change of water vapor gas etc. generated when the food is heated, it indirectly informs the heating condition or doneness of the food. Based on this information, automatic cooking will be performed by switching the heating method or stopping heating. A conventional example will be explained below with reference to Figures 4 to 6. As shown in FIG. 4, the box-shaped body 27 has a door 26 that can be opened and closed at the opening of the heating chamber 1, and a door 26 for selecting and setting the heating means, heating time, and heating method, and instructions for starting and stopping heating. An operating section 2l for input settings is provided on the front of the aircraft body 27. Further, the side wall of the fuselage 27 is surrounded by an outer shell plate 7. Figure 5 shows the components of the equipment.
A magnetron 11 as a high-frequency heating means is attached and connected to the heating chamber 1 in which the object to be heated 13 is housed. A high voltage transformer 9 for generating high voltage is placed near the magnetron 11. Further, a lamp lO for illuminating the heated proboscis l3 in the heating chamber 1 is arranged on the side wall of the heating chamber l. Further, an electric motor 12 for rotating a rotary table on which an object to be heated 13 is placed is arranged below the heating chamber l. Here, we will explain the components and operations. Heated object l
Place the food No. 3 in the heating chamber 1, close the door 26, select and press the automatic cooking switch on the operation section 21,
Furthermore, operate the start switch to start heating.
The operation signal of this start switch is transmitted to the control means 22, and the control means 22 outputs a drive signal from the drive means 23 to drive the magnetron 1l, the high voltage transformer 9, the electric motor 12, the blower 8, etc. When heating starts, the blower 8 sucks air from outside the fuselage through the hole 29 provided in the outer shell plate 7, and cools the magnetron 11, high voltage transformer 9, lamp lO, etc. by making use of the orifice l8 as an air rectifying wall. Air is sent into the heating chamber l. The air sent into the heating chamber 1 contains the object to be heated 13 and the water vapor gas coming out of the heating chamber 1.
Aircraft 2 from the exhaust port 15 and exhaust port 20 provided on the outer shell plate 7 through the exhaust hole 14 and exhaust hole 19 provided on the wall of the aircraft.
7 is discharged outside. A gas passage 2 is provided between the exhaust holes 14 and 19 of the heating chamber l and the exhaust ports l5 and 20 of the outer shell plate 7. A heating chamber i of a changing section 4, which is a portion having a changing cross-sectional area, provided in the middle of this gas passage 2.
It has a stable part as a constant range of cross-sectional area provided on the side, and a pyroelectric sensor 3 for detecting hot water vapor and gas is arranged in this changing part. The flat part of the heat receiving surface 28 of the pyroelectric sensor 3 that detects hot air is fixed to the inner surface of the passage, and the flow of exhaust air from the heating chamber l through the gas passage 2 and out of the fuselage 27 is pyroelectrically After passing over the heat receiving surface 28 of the sensor 3 and touching the heat receiving surface, it is discharged. Further, this gas passage 2 includes a first passage 16 that collects water vapor gas from the heating chamber 1 and a second passage 1 that guides the water vapor gas collected in the first passage 16 to the vicinity of the pyroelectric sensor 3.
7, and in order to facilitate the flow of air from the exhaust hole 14 provided in the heating chamber 1 to the stable part 5 provided in the middle of the gas passage 2, there are a first passage 16, a second passage 17, and a stable part. The configuration is such that there is no difference of more than 30% in the cross-sectional area of the passage between the The amount of exhaust gas discharged from the exhaust hole 14 of the heating chamber 1 of the gas passage 2 passes through the first passage 16, the second passage 17, the stable part 5, and the passage opening 6, and changes as it hits the heat receiving surface 28 of the pyroelectric sensor 3. After passing through the section 4, it is discharged from the discharge port l5 of the outer shell plate 7 as a displacement Qt. In this way, as the object to be heated 13 is heated and water vapor gas comes out from the food in the air flow generated by the blower 8, the water vapor gas passes through the gas passage 2 and reaches the heat receiving surface 28 of the pyroelectric sensor 3. One pyroelectric sensor 3 generates a pulse voltage signal when it comes in contact with water vapor gas and hot air. This generated electrical signal is transmitted to the sensor signal processing means 24 and then transmitted to the control means 22 via a voltage amplification circuit, a frequency filter circuit, a DC cut circuit, etc. Then, the control means 22 determines the state of the sensor signal voltage and selects whether to continue heating or stop heating,
Heating is ultimately stopped when the most desirable heating state is achieved. The pyroelectric sensor 3 used in the heating operation described above is a pyroelectric sensor in which when thermal energy is applied, the equilibrium state of the internal polarization of the element is disturbed and a pulse voltage is generated at the electrode section provided on the element surface. It uses elements that have an effect. Generally known products such as piezoelectric buzzers in dielectric ceramics, ultrasonic vibrating elements, piezoelectric ceramics used in ultrasonic detection elements, and piezoelectric resin films play a sufficient role as pyroelectric sensors. Problems to be Solved by the Invention However, in the above configuration, the flow of exhaust air from the heating chamber 1 passes over the heat receiving surface 28 of the pyroelectric sensor 3 and, after touching the heat receiving surface 28, flows out of the fuselage 27. However, in order for the water vapor gas from the object to be heated 13 generated in the heating chamber 1 to reach the heat receiving surface 28 of the pyroelectric sensor 3, it must be moved from the heating chamber 1 to the first passage 1 by the wind pressure generated by the blower 8.
6, second passage l7, stable part 5, passage opening 6 and changing part 4
However, since the air sent into the heating chamber 1 is exhausted from the exhaust hole 14, 1902 exhaust holes, and the gap between the door 26 and the heating chamber 1, air is generated in the heating chamber 1. Only a portion of the water vapor gas is delivered to the pyroelectric sensor 3 via the gas passage 2. Therefore,
Even when the object to be heated 13 is heated in the heating chamber 1 and water vapor gas comes out, the water vapor gas flows through the long path of the gas passage 2 based only on the wind pressure of the air blower 4lIlB until it reaches the heat receiving surface of the pyroelectric sensor 3. It often takes a long time to heat the heated object 13.
Since the heating state of the heated object 13 cannot be detected promptly, the heated object 13 becomes overheated, and even though the automatic heating device should stop heating the heated object 13 at the optimum heating state, it is not in the optimum state. The problem was that the automatic heating device could not perform its original function of being unable to stop the heating. Therefore, in the present invention, a cold air mixing exhaust passage is provided in the change section in which the pyroelectric sensor 3 is housed in the gas passage 2 for mixing and discharging the cold air from the blower, and the ventilation exhaust air speed is increased to partially discharge the cold air. The purpose of the present invention is to provide an automatic heating device that does not overheat an object to be heated 13 by lowering the atmospheric pressure and arranging the device so as to suck out exhaust air from a gas passage 2 connected to a heating chamber 1. ．． Means for Solving the Problems Therefore, in order to achieve the above object, the present invention provides a cold air mixing exhaust passage for mixing and discharging cold air from the blower in the changing section, and increases the ventilation exhaust air speed to partially exhaust the cold air. It is constructed and arranged so that the air pressure is lowered and the exhaust air from the gas passage connected to the heating chamber is sucked out. Function: The automatic heating device of the present invention has a cold air mixing exhaust passage for mixing and discharging cold air from the blower in the changing section that houses the pyroelectric sensor, and increases the ventilation/exhaust air speed of this mixing exhaust passage to partially heat the air. At the position where the atmospheric pressure is lower,
By arranging the exhaust port of the gas passage connected from the heating chamber, the exhaust air containing water vapor gas from the heating chamber is sucked out. Therefore, the time it takes for the heat of the steam gas from the object to be heated contained in the exhaust air from the heating chamber to be detected by the heat receiving surface of the pyroelectric sensor does not become long. As a result, the detection time of water vapor gas becomes slow, and the heating state of the object to be heated can be detected by the pyroelectric sensor as a state in which heating should be stopped. Therefore, it is possible to prevent the object to be heated from being overheated, so that the automatic heating device can fully perform its original function. EXAMPLE Below, an automatic heating device according to an example of the present invention will be explained with reference to the drawings. As shown in FIG. 2, a magnetron 11 as a high-frequency heating means is attached and connected to a heating chamber l in which an object to be heated 13 is housed. A high voltage transformer 9 for generating high voltage is placed near the magnetron 1l. Further, a lamp lO for illuminating the object to be heated 13 in the heating chamber l is arranged on the side wall of the heating chamber l. Further, an electric motor 12 that rotates a rotary table on which an object to be heated 13 is placed is arranged below the heating chamber 1. Here, we will explain the components and operations. Place the food as the object to be heated 13 in the heating chamber 1 and
6, select and press the automatic heating cooking switch on the operating section 2l, and then operate the start switch to start heating. The operation signal of this start switch is transmitted to the control means 22, and from the control means 22, a drive signal for driving the magnetron 11, the high voltage transformer 9, the electric motor 12, the blower 8, etc. is outputted from the drive means 23. When heating starts, the blower 8 sucks air from outside the fuselage through the hole 29 provided in the outer shell plate 7, and cools the magnetron 11, high-voltage transformer 9, lamp 10, etc. by utilizing the orifice l8 as an air rectifying wall. Air is sent into heating chamber 1. The air sent into the heating chamber 1 contains water vapor gas coming out from the object to be heated l3, and passes through the exhaust hole 14 and the exhaust hole l9 provided on the wall of the heating chamber 1, and then through the exhaust port provided on the outer shell plate 7. 15 and discharge port 20 to the outside of the aircraft body 27. A gas passage 2 is provided between the exhaust holes 14 and 19 of the heating chamber l and the exhaust ports l5 and 20 of the outer shell plate 7. This gas passage 2
The stable part 5 is a constant range of cross-sectional area provided on the heating chamber 1 side of the changing part 4, which is a part where the cross-sectional area is changing, and the boundary where the stable part 5 switches to the changing part 4. A pyroelectric sensor 3 for detecting water vapor and hot gas is disposed in the changing section 4. Here, we will explain Figure 1. Air is blown to a changing part 4, which is a part where the cross-sectional area changes, provided in the middle of the gas passage 2.
Cold air mixing exhaust passage 2 for mixing and discharging cold air from
5 is provided to increase the speed of ventilation exhaust air in this cold air mixing exhaust passage 25 to partially lower the atmospheric pressure, and the vent of the gas passage 2 connected to the heating chamber 1 is arranged at a position where the atmospheric pressure is lowered. When heating the object 13 to be heated, the blower 8
Wind pressure is applied to the heating chamber 1 by the air blowing, and at the same time, the ventilation air speed in the cold air mixing exhaust passage 25 increases, and as the wind speed increases, the air pressure locally decreases a little, and the gas passage 2
As a result, a change in the state of the hot water vapor gas from the object to be heated 13 is quickly transmitted to the heat receiving surface 28 of the pyroelectric sensor 3. Therefore, the detection of the heating state of the object to be heated 13 is delayed and the object to be heated 13 is not overheated. The gas passage 2 includes a first passage l6 that collects water vapor gas from the heating chamber l and a second passage l7 that guides the water vapor gas collected in the first passage l6 to the vicinity of the pyroelectric sensor 3. In order to facilitate the flow of air from the exhaust hole 14 provided in the gas passage 2 to the stable part 5 provided in the middle of the gas passage 2, the first
The passage 16, the second passage 17, and the stable portion 5 are configured so that there is no difference of more than 30% in the cross-sectional area of the passage. The amount of gas discharged from the exhaust hole 14 of the heating chamber 1 into the gas passage 2 is Q. After passing through the first passage 16, the second passage 17, the stable part 5, and the passage opening 6, it hits the heat receiving surface 28 of the pyroelectric sensor 3, and is mixed with the air Q sent from the cold air mixing exhaust passage 25 in the changing part 4. It is discharged from the discharge port 15 of the outer shell plate 7 as a displacement amount Q8.

As described above, there are two types of air flows generated by the blower 8: a flow due to the wind pressure sent out from the heating chamber 1, and a flow due to the drop in air pressure created in the cold air mixing exhaust passage 25. As the heating of the object l3 in the air progresses and steam gas comes out from the food, the steam gas passes through the gas passage 2 and hits the heat receiving surface 28 of the pyroelectric sensor 3. The pyroelectric sensor 3 emits a pulse voltage signal when it comes into contact with water vapor gas and hot air. This generated electric signal is transmitted to the sensor signal voltage processing means 24, and is transmitted to the control means 22 through a voltage amplification circuit, a frequency filter circuit, a DC cut circuit, etc. Then, the control means 22 determines the state of the sensor signal voltage and selects whether to continue heating or, if it is, to stop heating, and finally at the stage when the most desirable heating state is obtained. This will stop heating. The pyroelectric sensor 3 used in the heating operation described above is a pyroelectric sensor in which when thermal energy is applied, the equilibrium state of the internal polarization of the element is disturbed and a pulse voltage is generated at the electrode section provided on the element surface. It uses elements that have an effect. Generally known products such as piezoelectric buzzers in dielectric ceramics, ultrasonic vibration elements, piezoelectric ceramics used in ultrasonic detection elements, and piezoelectric resin films play a sufficient role as the pyroelectric sensor 3. Next, another embodiment of the present invention will be explained with reference to FIG. As shown in FIG. 3, a blower 8 is installed in the cold air mixing exhaust passage 25.
The cold air sucked in from outside the fuselage 27 is sent in, passes through the changing part 4, passes through the exhaust port 15, and is discharged to the outside of the fuselage 27. At this time, since the flow of the incoming air is fast, the air pressure at the passage opening 6, which is the end of the stable part 5 of the gas passage 2, decreases, and the exhaust air from the heating chamber 1 is sucked out, so that the heating chamber After the water vapor gas contained in the exhaust air from l comes into contact with the heat receiving surface 28 below the pyroelectric sensor, it flows upward and then toward the exhaust port 15 of the outer shell plate 7 and exits from the exhaust port 15 to the outside of the fuselage 27. I'm going to go. In this way, when the flow of exhaust air is mixed with cold air, the pressure decreases, and water vapor gas is sucked out and is transferred to the heat receiving surface 2 of the pyroelectric sensor 3.
8, the pyroelectric sensor 3 quickly detects an increase in the steam gas heat due to a change in the state of the heated object 13 occurring in the heating chamber 1. Since the heating state of the object to be heated 13 is detected without delay, there is an effect that the object to be heated 13 is prevented from being overheated. Next, another embodiment of the present invention will be explained with reference to FIG. As shown in FIG. 7, a blower 8 is installed in the cold air mixing exhaust passage 25.
The cold air sucked in from outside the fuselage 27 is sent in, passes through the changing part 4, passes through the exhaust port 15, and is discharged to the outside of the fuselage 27. At this time, since the flow of the incoming air is fast, the air pressure on the side of the outlet 15 of the transition part 4 of the gas passage 2 decreases, and the exhaust air from the heating chamber l is sucked out. After the water vapor gas contained in the exhaust air touches the heat-receiving surface 28 below the pyroelectric sensor, it flows upward and then heads toward the exhaust port l5 of the outer shell plate 7.
5 and will exit the aircraft 27. In this way, the water vapor gas that is sucked out due to the pressure drop when the exhaust air is mixed with cold air and touches the heat receiving surface 28 of the pyroelectric sensor 3 causes a change in the state of the heated object l3 that occurs in the heating chamber l. The pyroelectric sensor 3 quickly detects the increase in hot water vapor gas due to Since the heating state of the object to be heated 13 is detected without delay, there is an effect that the object to be heated 13 is prevented from being overheated. Effects of the Invention As described above, the automatic heating device of the present invention provides the following effects. Cold air sucked in from outside the aircraft by a blower is sent into the cold air mixing exhaust passage, and is rapidly discharged from the aircraft through the transition area, the exhaust port, and the exhaust port. At this time, the flow of the incoming air is fast, so the air pressure around the changing part of the gas passage decreases, and the exhaust air from the heating chamber is sucked out, causing the water vapor contained in the exhaust air from the heating chamber to drop. After the gas touches the heat-receiving surface under the pyroelectric sensor, it heads toward the exhaust port on the outer shell plate and exits the aircraft through the exhaust port.
In this way, when the flow of exhaust air is mixed with cold air, water vapor gas is sucked out due to the drop in pressure at the changing part and comes into contact with the heat receiving surface of the pyroelectric sensor, causing a change in the state of the heated object that occurs in the heating chamber. The pyroelectric sensor quickly detects the increase in water vapor and hot air caused by the pyroelectric sensor. Since the heating state of the heated object is detected without delay, it is effective in preventing the heated object from being overheated.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the main parts of an automatic heating device according to an embodiment of the present invention, Fig. 2 is a diagram of its overall configuration, Fig. 3 is a sectional view of main parts of another embodiment of the invention, and Fig. FIG. 5 is a perspective view of the appearance of a conventional automatic heating device, FIG. 5 is an overall configuration diagram thereof, FIG. 6 is a sectional view of a main part thereof, and FIG. 7 is a sectional view of a main part of another embodiment of the present invention. 1... Heating chamber, 2... Gas passage, 3... Pyroelectric sensor, 4... Changing section,
5... Stable part, 6... Passageway entrance, 25.
...Cold air mixing exhaust passage, 28...Heat receiving section. Name of agent: Patent attorney Shigetaka Awano (1 person) Figure 2l Figure z/ Figure 4

Claims (1)

[Claims] a heating chamber for placing an object to be heated; a gas passage for exhausting water vapor and gas from the object to be heated generated in the heating chamber; a pyroelectric sensor for detecting hot air of the vapor and gas; a heat-receiving surface of the pyroelectric sensor that becomes a part of the inner wall surface of the gas passage; a stable part of the pyroelectric sensor in the gas passage that is closer to the heating chamber than the pyroelectric sensor; An automatic heating device comprising a changing section, which is a range, and a cold air mixing exhaust passage for mixing cold air into the changing section and discharging the mixture.