JPH02293527A - Automatic heating device - Google Patents

Abstract

PURPOSE:To prevent an over-heating of a heated item by a method wherein a direction of a flow of evacuation air flowing from a stable part toward a heat receiving surface of pyroelectric sensor is not coincided with a vertical direction of the heat receiving surface. CONSTITUTION:A stable part 5 having a specified range of a sectional area arranged at a heating chamber 1 of a varying part 4 acting as a part where the sectional are a varies is arranged in the midway part of a fast passage 2 and a passage port 6 acting as an interface changing-over from the stable part 5 to a varying part 4 is provided. The varying part 4 is provided with a pyroelectric sensor 3 for use in detecting water vapor and heat from gas. This configuration is made such that a vertical direction perpendicular to a flat receiving surface 28 of the pyroelectric sensor 3 is not coincided with a linear arrangement of the stable part 5 and the passage port 6. A flow of evacuation air passing through a gas passage 2 and flowing out of a machine body is not struck against a front surface at the heat receiving surface 28 of the pyroelectric sensor 3 and is smoothly flowed out of the machine body. Hot gas of the water vapor from the heated item 13 generated in the heating chamber 1 is rapidly transmitted to the heat receiving surface 28 of the pyroelectric sensor 3, the heating condition of the heated item 13 is detected and the heating is stopped under the most appropriate state.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention detects the hot air contained in steam and gas that comes out depending on the heating state of the object to be heated, and appropriately determines the heating end time of the object to be heated. This article relates to an automatic heating device that achieves a heating state that is consistent with the 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 3 to 5. As shown in FIG. 3, 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 4 shows the components of the equipment.
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 11. Further, a lamp 10 for illuminating the object to be heated 13 in the heating chamber 1 is arranged on the side wall of the heating chamber 1. 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. Heated object 1
Place the food item No. 3 in the heating chamber l, close the door 26, select and press the automatic cooking switch on the operation unit 2l,
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 for driving the magnetron 11, 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 10, etc. by making use of the orifice 18 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 13, and the air is fed into 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 l4 and 19 of the heating chamber 1 and the exhaust ports l5 and 20 of the outer shell plate 7. A heating chamber l of a changing section 4, which is a portion with 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. Here, we will explain Figure 5. There is a stable part 5 in a direction perpendicular to the flat part of the heat receiving surface 28 of the pyroelectric sensor 3 that detects hot air, and the flow of exhaust air flowing from the heating chamber 1 through the gas passage 2 to the outside of the fuselage 27 changes. Pyroelectric sensor 3 in section 4
This results in a head-on collision with the heat receiving surface 28. The gas passage 2 also includes a first passage 16 that collects steam gas from the heating chamber l and a second passage 17 that guides the steam gas collected in the first passage 16 to the vicinity of the pyroelectric sensor 3. A stable part 5 provided in the middle of the gas passage 2 from the wandering hole l4 provided in the
In order to facilitate the flow of air up to
The structure is such that there is no difference of more than 30% in the cross-sectional area of the passage between the second passage l7 and the stable part 5. The amount of exhaust gas discharged from the exhaust hole l4 of the heating chamber 1 of the gas passage 2 Q. is the first
It passes through the passage l6, the second passage 17, the stable part 5, and the passage opening 6, hits the heat receiving surface 28 of the pyroelectric sensor 3, passes through the changing part 4, and is then discharged from the discharge port 15 of the outer shell plate 7 as an exhaust amount Q8. 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. It's true. The pyroelectric sensor 3 generates a pulse voltage signal when exposed to water vapor gas and hot air. The generated electrical signal is transmitted to the sensor signal processing means 24, and is transmitted to the control stage 22 via a voltage amplification circuit, a frequency filter circuit, a DC cut circuit, etc. Then, in the control stage 22, the state of the sensor signal voltage is judged and a selection is made as to whether to continue heating or to 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 collides head-on with the heat receiving surface 28 of the pyroelectric sensor 3, and the air flow generated by the blower 8 is blocked at one end by the heat receiving surface of the pyroelectric sensor 3, making it impossible to obtain a smooth flow of exhaust air and causing the heating chamber 1
The water vapor gas of the heated object l3 generated in the pyroelectric sensor 3
It is delayed in reaching the heat receiving surface 28 of the object to be heated, and furthermore, it is delayed in detecting the hot air due to steam gas from the object to be heated 13 for indirectly detecting the heated state of the object to be heated 13. In this way, if the time for detecting the hot air of water vapor gas is delayed, even if the heating state of the object to be heated 13 is such that heating should be stopped, the pyroelectric sensor 3 will not be able to detect this state. Therefore, there was a problem in that the object to be heated 13 was heated too much and the automatic heating device could not perform its original function. Therefore, in the present invention, the flow of exhaust air from the heating chamber through the gas passage is made smooth so that the water vapor gas from the heated object generated in the heating chamber quickly reaches the heat receiving surface of the pyroelectric sensor. The purpose is to provide an automatic heating device that does not overheat the heated object. Means for Solving the Problems To achieve the above object, the present invention provides a pyroelectric sensor having a heat receiving surface exposed in a gas passage for exhausting and guiding air in a heating chamber to the outside of the aircraft, and a pyroelectric sensor that A stable part, which is a gas passage on the heating chamber side and has a stable cross-sectional area of the passage, is provided, and the direction of the exhaust air flow flowing from this stable part toward the heat receiving surface of the pyroelectric sensor does not coincide with the vertical direction of the heat receiving surface. The structure and arrangement are as follows. Function: The automatic heating device of the present invention is constructed and arranged so that the direction of the exhaust air flowing from the stable part toward the heat receiving surface of the pyroelectric sensor does not coincide with the vertical direction of the heat receiving surface. will not collide head-on with the heat-receiving surface of the pyroelectric sensor at the changing part. Therefore, a smooth flow of exhaust air can be realized without the exhaust air flow stopping once at the heat-receiving surface. As a result, the flow of air generated by the blower is no longer blocked by the heat-receiving surface of the pyroelectric sensor, and a smooth flow of exhaust air is obtained, which allows the object to be heated generated in the heating chamber to flow smoothly. There is a delay in the water vapor gas reaching the heat receiving surface of the pyroelectric sensor, and furthermore, there is a delay in detecting the hot air due to the water vapor gas from the heated object to indirectly detect the heated state of the heated object. It disappears. In this way, if the time for detecting the hot air of water vapor gas is reduced, the pyroelectric sensor will be able to detect when the heating state of the object to be heated is such that 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 demonstrate 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 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 10 for illuminating the object to be heated 13 in the heating chamber 1 is arranged on the side wall of the heating chamber 1. 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 1. Here, we will explain the components and operations. Food as the object to be heated 13 is placed in the heating chamber 1 and the door 26 is opened.
Close the , 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 this control means 22, a drive signal for driving the magnetron l1, the high voltage transformer 9, the electric motor l2, the air blower 1a8, 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 heats the magnetron IL high-voltage transformer 9, lamp lO, etc. while cooling them by utilizing the orifice 18 as an air rectifying wall. Room 1
It's blowing air in. The air sent into the heating chamber 1 contains water vapor gas coming out from the object to be heated l3, and the air is connected to an exhaust hole 14 provided on the wall of the heating chamber 1 and an exhaust hole 1.
9. Discharge port 15 and discharge port 20 provided in outer shell plate 7
It is ejected from the fuselage 27. The gas passage 2 is connected from the exhaust holes 14 and 19 of the heating chamber l to the exhaust port l5 of the outer shell plate 7.
, up to 20. A changing section 4 provided in the middle of this gas passage 2 as a section where the cross-sectional diameter changes.
The heating chamber l side is provided with a stable part 5 as a constant range of cross-sectional diameter and a passage opening 6 which is the boundary where the stable part 5 switches to the changing part 4. A pyroelectric sensor 3 for detection is installed. Here, FIG. 1 will be explained. The arrangement is such that the direction perpendicular to the flat surface of the heat receiving surface 2B of the pyroelectric sensor 3 that detects hot air does not match the linear arrangement direction of the stable part 5 and the passage opening 6, and the gas from the heating chamber 1 The flow of exhaust air passing through the passage 2 and exiting the fuselage 27 smoothly flows out of the fuselage without colliding head-on with the heat receiving surface 28 of the pyroelectric sensor 3 at the transition section 4. The gas passage 2 has a first passage l6 that collects steam gas from the heating chamber 1 and a second passage l7 that guides the steam gas collected in the first passage 16 to the vicinity of the pyroelectric sensor 3. In order to facilitate the flow of air from the provided exhaust hole 14 to the stable part 5 provided in the middle of the gas passage 2, the first passage 1
6, the second passage 17 and the stable part 5 have a passage cross-sectional area of 3
The configuration is such that there is no difference of more than 30%. The amount of gas discharged from the exhaust hole l4 of the heating chamber 1 into the gas passage 2 is Q. passes through the first passage 16, the second passage 17, the stable part 5, and the passage opening 6, hits the heat receiving surface 28 of the pyroelectric sensor 3, passes through the changing part 4, and is then discharged from the discharge port 15 of the outer shell plate 7 as an exhaust amount Q2. It will be done. In this way, when the heated object 13 is heated in the air flow generated by the air blower [8] and water vapor gas comes out from the food, the water vapor gas passes through the gas passage 2 and reaches the heat receiving surface 28 of the pyroelectric sensor 3. It's true. The pyroelectric sensor 3 generates a pulse voltage signal when exposed to 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 judges the state of the sensor signal voltage and chooses whether to continue heating or stop heating, and finally starts heating when the most desirable heating state is obtained. It will stop. The pyroelectric sensor 3 used in the heating operation described above is a pyroelectric sensor that, when thermal energy is applied, disturbs the equilibrium state of the internal polarization of the element and generates a pulse voltage on the electric scratching part provided on the surface of the element. It uses elements that have a sexual 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. 6, the direction in which the exhaust air flows is substantially perpendicular to the direction perpendicular to the heat receiving surface 28 of the pyroelectric sensor 3, and the exhaust air flows from the stable part 5 toward the vent 6. Even when the flow enters the changing section 4, the direction of flow is not drastically changed, and it proceeds straight to the outlet 15 of the outer shell 1j7, and exits from the outlet 15 to the outside of the fuselage 27. As the air is discharged to the outside of the aircraft without interrupting the flow of exhaust air, the hot air of the steam gas generated in the heating chamber 1 is quickly transmitted to the pyroelectric sensor 3, and the object to be heated is Since the heating state of the heated object 13 is detected without delay, there is an effect of preventing the heated object 13 from being overheated. Effects of the Invention As described above, the automatic heating device of the present invention provides the following effects. The vertical direction of the heat-receiving surface of the pyroelectric sensor that detects hot air with respect to the flat surface of the sensor does not match the linear arrangement direction of the stable part and the passageway opening, so that the air does not go out of the aircraft from the heating chamber through the gas passageway. 《The flow of exhaust air does not collide head-on with the heat receiving surface of the pyroelectric sensor at the transition part, and the exhaust air resistance is reduced, so the exhaust air flows smoothly out of the aircraft, and the heating chamber The heat of the generated water vapor gas from the heated object is quickly transferred to the heat receiving surface of the pyroelectric sensor, and the heating state of the heated object is detected and the heated object is heated in the optimal state. This has the effect of stopping the

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a sectional view of essential parts of an automatic heating device according to an embodiment of the present invention, FIG. 2 is an overall configuration diagram thereof, and FIG. 3 is an external perspective view of a conventional automatic heating device. Figure 4 is the overall configuration diagram, Figure 5
The figure is a sectional view of the main part, and FIG. 6 is a sectional view of the main part of another embodiment of the present invention. l... Heating chamber, 2...
・Gas passage, 3...Pyroelectric sensor, 4...
・Variable part, 5... Stable part, 6... Passage opening, 28... Heat receiving part. Name of agent: Patent attorney Shigetaka Awano and one other person I... Kazutomo a#! ．． Figure 2l Figure 2

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; a changing part that is a range, and a passage opening that is a boundary where the ventilation cross-sectional area of the gas passage changes from the stable part to the changing part, and a pyroelectric sensor detects the straight direction of exhaust air flowing from the stable part to the passage opening. Automatic heating device configured so that the heat receiving surface is not perpendicular to the heating surface.