JP2011085293A - Water amount detector and steam cooker using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect an amount of water in a pot without using an electrode-type water level sensor in a pot type steam generator using no water tank. <P>SOLUTION: At the time of low-temperature start or in a state of the low-temperature start, a water amount detecting part 38 determines that there is a large amount of water in the water pot 15 (full capacity) if elapsed time after the low-temperature start reaches regulated time of 300 sec before a temperature of an engine thermistor 36 reaches set temperature of 90°C or higher. On the other hand, the water amount detecting part 38 determines that there is a small amount of water in the water pot 15 (less than the full capacity) if the temperature of the engine thermistor 36 becomes the set temperature of 90°C or higher before the elapsed time after the low-temperature start reaches the regulated time of 300 sec. The amount of water in the water pot 15 is detected thereby without using an electrode type water level sensor, in the pot type steam generator using no water tank. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a water amount detection device that detects the amount of water, such as a steam generation device, and a steam cooker including the same.

  As a steam generation device having a water amount detection device, there is a saturated steam supply unit disclosed in Japanese Patent Laid-Open No. 2003-262338 (Patent Document 1). The saturated steam supply unit includes a steam generating can body and a water supply tank, and generates saturated steam from water. Specifically, water is supplied from the water supply source to the water supply tank through the water supply electromagnetic valve, the water is filled into the steam generation can body by a pump, heated by the steam generation heater, and saturated steam is generated. Generated.

  The water tank is provided with a full water level detection sensor for detecting the water level when the water is full and a low water level detection sensor for detecting the water level when the water is drought. The steam generating can is provided with a water level sensor that detects the presence or absence of water.

  In the saturated steam supply unit disclosed in Patent Document 1, the water supply tank and the steam generating can body are provided with a water level sensor. However, the water level sensors installed in the water supply tank are a full water level detection sensor and a low water level detection sensor, and can only know whether the water supply tank is full or drought. The water level sensor installed in the steam generating can body is a water level sensor that detects the presence or absence of water, and only knows whether there is a predetermined amount of water set in advance in the steam generating can body. I can't. Therefore, at present, there is a problem that it is impossible to detect the level of water in the water supply tank and the steam generating can.

  Therefore, there is a steam generator and a water tank disclosed in Japanese Patent Laid-Open No. 2007-33005 (Patent Document 2) as a steam generator capable of detecting an intermediate water level between full water and drought in a water supply tank. As shown in FIG. 10, when the water tank 51 is connected to the joint portion 52, the steam generator and the water tank flow into the sensor unit 53 via the joint portion 52, and the same as the water tank 51. Water rises in the sensor unit 53 until the water level is reached. Accordingly, the water level in the water tank 51 is detected by detecting the water level in the sensor unit 53 by the water level sensor 54 for the water tank. Here, the water level sensor 54 for the water tank includes a tank GND electrode 54a and tank detection electrodes 54b, 54c and 54d. Of the tank detection electrodes 54b, 54c, 54d that are electrically connected to the tank GND electrode 54a, the positions of the front ends of the tank detection electrodes 54b, 54c, 54d that are located at the uppermost positions are designated as the water tank 51. It is detected as the water level inside.

  When the pump 55 is driven, water is supplied from the water tank 51 through the auxiliary tank 56 into the pot 58 of the steam generator 57, and the water level in the pot 58 is always the same as the water level in the auxiliary tank 56. . Therefore, the water level in the pot 58 is detected by detecting the water level in the auxiliary tank 56 with the auxiliary tank water level sensor 59.

  However, the conventional steam generator and water tank disclosed in Patent Document 2 have the following problems.

  That is, as described above, when detecting an intermediate water level between full water and drought in the water tank 51, a water tank water level sensor having a number of tank detection electrodes corresponding to the number of intermediate detection water levels. 54 is required, and it becomes difficult to install the water level sensor 54 for the water tank directly on the water tank 51. Therefore, it is necessary to provide a sensor unit 53, which is a container for detecting the water level in the water tank 51, separately from the water tank 51, and the water tank 51 is applied to an oven-type or grill-type cooking device. This is effective in the case of a heating cooker that can be used. However, when an IH heater and a roaster unit are installed in one cabinet as in the case of an IH (electromagnetic induction heating) cooking heater, when a sufficient space cannot be secured in the water supply unit, pot-type steam that does not use the water tank 51 is used. There is a problem that it is necessary to use a generator and it cannot be applied. Furthermore, when the water tank 51 is removed from the sensor unit 53, the water in the sensor unit 53 is exhausted, so that it is unsuitable for use in a pot-type steam generator that does not supply enough water. There is also a problem.

  Further, as the water tank water level sensor 54 disclosed in Patent Document 2, the tank GND electrode 54a and tank detection electrodes 54b, 54c, 54d are used. Thus, it is not preferable for safety to install the electrode at the place where water is handled. In addition, there is a problem that the water level in the water tank 51 is erroneously detected due to the boiling of water in the pot 58 or the dew condensation generated between the tank detection electrodes 54b, 54c, 54d.

JP 2003-262338 A Japanese Patent Laid-Open No. 2007-33005

  Accordingly, an object of the present invention is to provide a water amount detection device capable of detecting the amount of water in a pot without using an electrode-type water level sensor in a pot type steam generator that does not use a water tank, and a steam cooker using the same. There is to do.

In order to solve the above problems, the water amount detection device of the present invention is
A water pot for storing water for steam generation;
A pot heater for heating the water pot to generate water vapor;
A water temperature detector that detects a temperature corresponding to the water temperature in the water pot and outputs a detection signal representing the detected temperature;
Based on the detection signal from the water temperature detection unit, the rate of increase of the water temperature in the water pot is obtained, and the rate of increase of the obtained water temperature and a set rate of increase set in advance according to the amount of water in the water pot, On the basis of the comparison result, a water amount detection unit for detecting the amount of water in the water pot is provided.

  According to the above configuration, the water amount detection unit obtains the rate of increase of the water temperature in the water pot based on the temperature corresponding to the water temperature in the water pot detected by the water temperature detection unit, and the obtained water temperature Is compared with a preset increase rate set in advance according to the amount of water in the water pot, and the amount of water in the water pot is detected. Therefore, in a pot-type steam generator that does not use a water tank, it is possible to detect the amount of water in the water pot without using an electrode-type water level sensor.

  Furthermore, when the amount of water in the water pot is detected at a plurality of levels, it is only necessary to increase the number of the set increase rates. Therefore, unlike the case where the electrode-type water level sensor is used, there is no need for a water tank or auxiliary tank for storing the number of electrode-type water level sensors corresponding to the number of detected water levels, and a sufficient space is provided in the water supply unit. Since it cannot be ensured, it can be applied to an IH cooking heater using a pot-type steam generator.

  Furthermore, since the electrode-type water level sensor is not used, it is not necessary to install an electrode at a location where water is handled, and a safe water amount detection device can be provided to the user, and erroneous detection caused by boiling or condensation of water can be provided. There is no problem.

Moreover, in the water amount detection device of one embodiment,
The water amount detection unit can control the on / off of the pot heater,
A water temperature detection unit in the pot that detects the water temperature in the water pot and outputs a detection signal representing the detected temperature,
The water amount detection unit has a first preset temperature at which an initial temperature of the water temperature in the water pot based on a detection signal from the water temperature detection unit in the pot is a temperature at which water vapor starts to be generated from a preset water surface in the pot. In the case of the above, the pot heater is once turned off, and the pot heater is turned on after the water temperature in the water pot reaches room temperature, and the rate of increase in the water temperature in the water pot is obtained. .

  According to this embodiment, the water amount detection unit temporarily turns off the pot heater when the initial temperature of the water temperature in the water pot is equal to or higher than the first set temperature at which water vapor starts to be generated from the water surface in the pot. Then, after the water temperature in the water pot reaches room temperature, the pot heater is turned on to obtain the rate of increase in the water temperature in the water pot. Therefore, even at the time of high temperature start when water vapor has already been generated from the water pot, the amount of water in the water pot can be accurately detected.

Moreover, in the water amount detection device of one embodiment,
The water volume detector
Including a timekeeping section for measuring the elapsed time since the pot heater was turned on,
The rate of increase of the water temperature in the water pot is to measure the elapsed time from when the pot heater is turned on until the temperature corresponding to the water temperature in the water pot reaches a preset temperature. Sought by,
The set increase rate is an elapsed time until a temperature corresponding to the water temperature in the water pot, which is preset according to the amount of water in the water pot, reaches the set temperature.

  According to this embodiment, the rate of increase of the water temperature in the water pot according to the elapsed time from when the pot heater is turned on until the temperature corresponding to the water temperature in the water pot reaches a preset temperature. Asking for. By doing so, it is possible to accurately obtain the rate of temperature increase in the case of water whose temperature change is not so large.

Moreover, in the water amount detection device of one embodiment,
The water volume detector
Including a timekeeping section for measuring the elapsed time since the pot heater was turned on,
The rate of increase of the water temperature in the water pot is the temperature corresponding to the water temperature in the water pot when the elapsed time counted by the time measuring unit reaches a preset set elapsed time. Sought by detecting,
The set increase rate corresponds to the water temperature in the water pot that is set in advance according to the amount of water in the water pot, and the elapsed time from when the pot heater is turned on becomes the set elapsed time. Temperature.

  According to this embodiment, the water temperature in the water pot is determined by the temperature corresponding to the water temperature in the water pot when the elapsed time since the pot heater is turned on reaches a preset elapsed time. The rate of increase is calculated. By doing so, it is only necessary to detect the temperature with the water temperature detection unit for each set elapsed time, and it becomes possible to detect the amount of water in the water pot in a short time.

Moreover, in the water amount detection device of one embodiment,
The said water temperature detection part is a water temperature detection part in a pot which detects the water temperature in the said water pot.

  According to this embodiment, the water temperature detection unit that detects the temperature corresponding to the water temperature in the water pot is configured as a pot water temperature detection unit that detects the water temperature in the water pot. Therefore, the water temperature in the water pot can be accurately detected.

Moreover, in the water amount detection device of one embodiment,
One end is connected to the water pot, and includes a steam passage to which water vapor generated in the water pot is supplied.
The water temperature detection unit is a gas temperature detection unit in the vapor passage that detects a gas temperature in the vapor passage.

  According to this embodiment, the water temperature detection unit that detects a temperature corresponding to the water temperature in the water pot is a steam that detects a gas temperature in the steam passage to which water vapor generated in the water pot is supplied. It is comprised by the gas temperature detection part in a channel | path. Therefore, it is possible to more reliably capture the generation of water vapor from the water pot.

Moreover, the steam cooker of this invention is
A water amount detection device of the present invention;
A steam generator including the water pot and the pot heater of the water amount detection device;
A heating chamber is provided in which steam generated in the water pot is supplied and cooking is performed using heat from the steam as a heat source.

  According to the said structure, the water quantity in the said water pot in the said steam generator which supplies water vapor | steam to the said heating chamber can be detected without using an electrode type water level sensor by the water quantity detection apparatus of this invention. Therefore, it is possible to provide a composite steam cooker or a small steam cooker having a heat source other than water vapor without requiring a water tank or auxiliary tank for housing the electrode type water level sensor.

In the steam cooker of one embodiment,
The water amount detection unit in the water amount detection device is capable of controlling on / off of the pot heater,
An internal temperature detector that detects the gas temperature in the heating chamber and outputs a detection signal representing the detected temperature,
The water amount detection unit is configured such that the initial temperature of the gas temperature in the heating chamber based on the detection signal from the internal temperature detection unit is a preset minimum temperature in the heating chamber during continuous operation in which continuous cooking is performed. When the temperature is equal to or higher than the second preset temperature, the pot heater is turned off, the pot heater is turned on after the water temperature in the water pot reaches room temperature, and the rate of increase in the water temperature in the water pot is determined. It comes to ask for.

  According to this embodiment, the water amount detection unit temporarily turns off the pot heater when the initial temperature of the gas temperature in the heating chamber is equal to or higher than the second set temperature, which is the lowest temperature during continuous operation. The pot heater is turned on after the water temperature in the water pot reaches room temperature, and the rate of increase in the water temperature in the water pot is obtained. Therefore, even during continuous operation in which cooking is performed continuously, the amount of water in the water pot can be accurately detected.

  As is clear from the above, the water amount detection device of the present invention obtains the rate of increase of the water temperature in the water pot based on the temperature corresponding to the water temperature in the water pot detected by the water temperature detection unit. In order to detect the amount of water in the water pot by comparing the obtained rate of increase of the water temperature with a preset rate of increase set in advance according to the amount of water in the water pot, an electrode type water level sensor is used. It is possible to detect the amount of water in the water pot. Therefore, the present invention can also be applied to a pot type steam generator that does not use a water tank.

  Furthermore, when the amount of water in the water pot is detected at a plurality of levels, it is only necessary to increase the number of the set increase rates. Therefore, unlike the case where the electrode-type water level sensor is used, there is no need for a water tank or auxiliary tank for storing the number of electrode-type water level sensors corresponding to the number of detected water levels, and a sufficient space is provided in the water supply unit It can also be applied to IH cooking heaters that cannot be secured.

  Furthermore, since the electrode-type water level sensor is not used, it is not necessary to install an electrode at a location where water is handled, and a safe water amount detection device can be provided to the user, and erroneous detection caused by boiling or condensation of water can be provided. The problem can be avoided.

  Moreover, the steam cooker of this invention can detect the water quantity in the water pot of the steam generator which supplies water vapor | steam to a heating chamber, without using an electrode type water level sensor by the water quantity detection apparatus of this invention. Therefore, it is possible to provide a composite steam cooker or a small steam cooker having a heat source other than water vapor without requiring a water tank or auxiliary tank for housing the electrode type water level sensor.

It is a perspective view in the IH cooking heater as an example of the steam cooker using the water amount detection apparatus of this invention. It is a front view of the state which removed the front panel in FIG. It is a figure which shows typically the steam path | route from the steam generator in FIG. 1, and the water quantity detection system of a water pot. It is a flowchart of the water amount detection processing operation in a pot performed based on the detection signal from the engine thermistor in FIG. It is a flowchart of the water amount detection processing operation in a pot performed based on the detection signal from the engine thermistor and steam thermistor in FIG. It is a flowchart of the water amount detection processing operation in a pot performed based on the detection signal from the engine thermistor and the internal thermistor in FIG. It is a flowchart of the water amount detection processing operation in a pot following FIG. It is a flowchart of the water amount detection processing operation in a pot following FIG. It is a figure which shows an example of a time-dependent change of the water temperature in case a pot is full of water, and the steam temperature in a steam channel. It is a figure which shows the structure of the conventional steam generator which can detect the water level in a water supply tank.

  Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

  FIG. 1 is a perspective view of an IH cooking heater as an example of a steam cooker using a pot-type steam generator as viewed from the front and obliquely above. FIG. 2 is a front view showing a state in which the front panel is removed in FIG.

  As shown in FIGS. 1 and 2, the present IH cooking heater has a top plate 2 provided on the upper surface of the cabinet 1 and two IH heaters, a right IH heater 3 and a left IH heater 4, on the front side. It is arranged with a gap. Further, a central IH heater 5 is arranged between the IH heaters 3 and 4 and on the rear side. An intake port 6 is provided on the right side of the rear surface side of the top plate 2, and an exhaust port 7 is provided on the left side of the rear surface side of the top plate 2. An IH operation unit 8 is disposed on the front side of the top plate 2. Here, the “front side” is the opening side of the heating chamber 10 of the roaster unit 9, and the “rear side” is the side opposite to the opening side of the heating chamber 10.

  Further, on the front side of the cabinet 1, a steam generator 12 is disposed in the center of the front panel 11, and a heating chamber 10 is disposed on the left side of the front panel 11. On the front side of the heating chamber 10 and the steam generator 12, there is provided a door 14 with a handle that is slidably mounted in the front-rear direction by rail units 13a and 13b.

  A packing (not shown) is attached around the opening of the heating chamber 10 in the front panel 11, and the periphery of the opening of the heating chamber 10 is sealed by the packing with the door 14 with a handle closed. . When the door 14 with the handle is closed, a gap for ventilation is provided between the front side of the steam generator 12 and the door 14 with the handle.

  The steam generator 12 includes a water pot 15 and a pot heater 16 that heats the water pot 15. As for this pot heater 16, the heating part protrudes from the bottom plate in the shape of a truncated cone. By heating the water pot 15 with the pot heater 16, the water in the water pot 15 boils and steam is generated. The steam generated in this way is supplied to the heating chamber 10, and in the heating chamber 10, the food is cooked by the steam supplied from the steam generator 12 and a heat source such as a sheathed heater.

  Further, a front operation unit 19 for the roaster unit 9 having a liquid crystal display unit 17 and an operation key unit 18 is disposed on the right side of the steam generator 12 in the front panel 11.

  As shown in FIG. 2, the roaster section 9 includes a heating chamber 10, an upper heater 20 made of, for example, a sheathed heater disposed above the heating chamber 10, and a sheath, for example, disposed at the lower portion of the heating chamber 10. The lower heater 21 made of a heater, the upper heater chamber 22 partitioned from the heating chamber 10 by a metal plate covering the upper heater 20, and the heating chamber 10 partitioned from the metal plate covering the lower heater 21. And a lower heater chamber 23. Thus, by storing the upper heater 20 and the lower heater 21 in the upper heater chamber 22 and the lower heater chamber 23, the oil from the heated food material adheres to both the heaters 20, 21. There is no smoke or fire, and both the heaters 20 and 21 can be prevented from being soiled.

  Further, on the rear side of the front operation unit 19 and on the right side of the steam generator 12, a right IH inverter circuit 24 for the right IH heater 3, a central IH inverter circuit 25 for the central IH heater 5, and A left IH inverter circuit 26 for the left IH heater 4 is stacked and disposed. In addition, 27 is a tray for putting a to-be-heated foodstuff.

  FIG. 3 schematically shows a steam path for supplying the steam generated by the steam generator 12 to the heating chamber 10 and a water amount detection system of the water pot 15 in the steam generator 12. The upper portion of the water pot 15 of the steam generator 12 is connected to the upper heater chamber 22 by a steam passage 31. Then, the saturated steam supplied to the upper heater chamber 22 through the steam passage 31 is jetted into the heating chamber 10 from a steam supply hole 32 formed on the lower surface of the upper heater chamber 22. At that time, the upper heater 20 is driven to further heat the saturated steam, whereby the superheated steam can be ejected into the heating chamber 10.

  That is, functions of the roaster section 9 in the present embodiment include grill cooking and oven cooking by the upper heater 20 and the lower heater 21, grill cooking and oven cooking by superheated steam from the steam supply hole 32, and steam supply hole 32. Steamed cooking with saturated steam from

  In that case, the upper heater chamber thermistor 33 for detecting the temperature in the upper heater chamber 22, the lower heater chamber thermistor 34 for detecting the temperature in the lower heater chamber 23, and the internal thermistor for detecting the temperature in the heating chamber 10. 35, and a heating cooking control unit (not shown) drives and controls the upper heater 20 and the lower heater 21 according to the detected temperatures from the upper heater chamber thermistor 33, the lower heater chamber thermistor 34, and the internal thermistor 35, The heated food in the heating chamber 10 is cooked.

  An engine thermistor 36 for detecting the water temperature in the water pot 15 is provided on the surface of the water pot 15 of the steam generator (engine) 12. The engine thermistor 36 may protrude into the water pot 15 and directly detect the water temperature in the water pot 15. A steam thermistor 37 that detects the gas temperature in the steam passage 31 is provided in the steam passage 31 that connects the water pot 15 and the upper heater chamber 22. The water amount detecting unit 38 detects a water temperature in the water pot 15 from the engine thermistor 36, a detection signal indicating a gas temperature from the steam thermistor 37, and a temperature in the heating chamber 10 from the internal thermistor 35. The amount of water in the water pot 15 is detected based on at least the detection signal from the engine thermistor 36 and the detection result is displayed on the liquid crystal display unit 17. is there.

  When the amount of water in the water pot 15 is large, since the heat capacity of the water in the water pot 15 is large, the temperature rise in the water pot 15 is slow. On the other hand, when the amount of water is small, since the heat capacity of the water in the water pot 15 is small, the water temperature in the water pot 15 rises quickly. Therefore, if the relationship between the amount of water in the water pot 15 and the rate of increase in the water temperature in the water pot 15 is examined in advance, the water amount detection unit 38 increases the water temperature in the water pot 15 based on the detection signal from the engine thermistor 36. If the rate is detected, the amount of water in the water pot 15 is known.

  FIG. 4 is a flowchart of the pot water amount detection processing operation that is executed based on the detection signal from the engine thermistor 36 as the pot water temperature detector under the control of the water amount detector 38. In this case, the amount of water in the pot is detected in a state where the detected temperature of the engine thermistor 36 is low at the initial stage (that is, when the pot heater 16 is switched from off to on at the start of cooking). If the rise is slow, it is determined that the water pot 15 is full. On the other hand, when the detected temperature rise by the engine thermistor 36 is fast, it is determined that the water pot 15 is less than full. Hereinafter, the pot water amount detection processing operation will be described in detail with reference to FIG.

  In step S1, based on the detection signal from the engine thermistor 36, it is determined whether or not the initial temperature of the water temperature in the water pot 15 is a high temperature of 90 ° C. or higher. As a result, if the temperature is high, the process proceeds to step S2, and if not, the process proceeds to step S10.

  In FIG. 9, when the amount of water in the water pot 15 is full at the time of a high temperature start at which cooking starts immediately after steam cooking has already been performed and at the time of a low temperature start at which cooking starts while steam cooking is stopped. An example of the change with time of the water temperature and the steam temperature in the steam passage 31 is shown.

  Usually, the water temperature when the water vapor starts to rise from the water surface in the water pot 15 is approximately 90 ° C. Therefore, in step S1, the determination temperature for determining whether the water temperature in the water pot 15 is high is set to “90 ° C.”. That is, if the initial temperature of the engine thermistor 36 is “90 ° C.” or higher, it is determined that the start is high, and the process proceeds to step S2, and if it is below “90 ° C.”, it is determined that the start is low and the process proceeds to step S10. is there.

  In step S2, since the initial temperature of the engine thermistor 36 is equal to or higher than “90 ° C.”, an increase in the temperature detected by the engine thermistor 36 cannot be measured as it is. Therefore, the pot heater 16 is turned off once, and the water temperature in the water pot 15 is lowered to a temperature at which a temperature rise can be detected.

  In step S3, it is determined whether or not a prescribed cooling time of 180 seconds defined in advance has passed, based on a timing signal from the timer 39 that is a built-in timing unit.

  Here, according to FIG. 9, the initial temperature of the water temperature in the water pot 15 at the time of the low temperature start is 25 ° C. Therefore, as an example of the specified cooling time, the time required for the water temperature in the water pot 15 to fall below the temperature in the vicinity of normal temperature may be used. In the present embodiment, “180 sec (3 minutes)” is set.

  In step S4, the pot heater 16 is turned on, and the process proceeds to a low temperature start in order to measure an increase in temperature detected by the engine thermistor 36. In step S5, it is determined whether or not the elapsed time after the low temperature start has reached a predetermined time 300 seconds that is specified in advance to determine that the amount of water in the water pot 15 is large. As a result, if the specified time has not been reached, the process proceeds to step S6, and if it has reached, the process proceeds to step S9.

  According to FIG. 9, when the amount of water in the water pot 15 is full, sufficient water vapor is supplied from the water pot 15 after the elapse of 360 seconds (6 minutes) after the start of low temperature. Therefore, the specified time for determining that the amount of water in the water pot 15 is large in step S5 is set to 300 seconds (5 minutes) after the low temperature start.

  In step S6, based on the detection signal from the engine thermistor 36, the temperature of the engine thermistor 36, that is, the water temperature in the water pot 15 is detected. In step S7, it is determined whether or not the detected temperature of the engine thermistor 36 has reached a preset temperature of 90 ° C. or higher that is set in advance to determine whether or not the water temperature in the water pot 15 is high. The As a result, if the temperature is equal to or higher than the set temperature, the process proceeds to step S8. Here, the set temperature is 90 ° C. at which water vapor starts to rise from the water surface in the water pot 15. In step S8, since the temperature of the engine thermistor 36 reaches the set temperature before the specified time has elapsed, it is determined that the heat capacity of the water in the water pot 15 is small and the amount of water in the water pot 15 is small. After that, the pot water amount detection processing operation is terminated.

  In step S9, it is determined that the heat capacity of the water in the water pot 15 is large and the amount of water in the water pot 15 is large because the specified time of 300 seconds elapses before the temperature of the engine thermistor 36 reaches the set temperature 90 ° C. Is done. After that, the pot water amount detection processing operation is terminated.

  In steps S10 to S15, since it is a low temperature start, it is determined whether or not the pot heater 16 is turned on and the elapsed time after the low temperature start has reached the specified time 300 seconds in the same manner as in steps S4 to S9. If not, the temperature of the engine thermistor 36 (that is, the water temperature in the water pot 15) is detected, and it is determined whether or not the temperature of the engine thermistor 36 has reached the set temperature 90 ° C. or higher. If there is, it is determined that the amount of water in the water pot 15 is small, and the pot water amount detection processing operation is terminated. On the other hand, if the specified time has elapsed before the temperature of the engine thermistor 36 reaches the set temperature, it is determined that the amount of water in the water pot 15 is large, and the pot water amount detection processing operation is terminated.

  As described above, when only the engine thermistor 36 for detecting the water temperature in the water pot 15 is provided, or only the engine thermistor 36 among the engine thermistor 36, the steam thermistor 37, and the internal thermistor 35 can operate. In the state, when the low temperature start or the low temperature start state is reached, the elapsed time after the low temperature start before the temperature of the engine thermistor 36 reaches the set temperature of 90 ° C. or more is the specified time. When 300 seconds are reached, it is determined that the amount of water in the water pot 15 is large. On the other hand, if the temperature of the engine thermistor 36 reaches the set temperature 90 ° C. or more before the elapsed time after the low temperature start reaches the specified time 300 seconds, it is determined that the amount of water in the water pot 15 is small. Like to do.

  Therefore, in a pot-type steam generator that does not use a water tank, the amount of water in the water pot 15 can be detected without using the electrode-type water level sensor.

  By the way, steam generated on the water surface in the water pot 15 is supplied to the steam passage 31 connecting the water pot 15 and the upper heater chamber 22. In that case, when the inside of the water pot 15 is full, steam is supplied to the steam passage 31 approximately 360 seconds (6 minutes) after the low temperature start. On the other hand, when the amount of water in the water pot 15 is ½ of the full water level, steam is supplied to the steam passage 31 approximately 180 seconds (3 minutes) after the start of low temperature. Therefore, in addition to the engine thermistor 36, when the steam thermistor 37 serving as the gas temperature detector in the steam passage for detecting the gas temperature in the steam passage 31 is provided, or the engine thermistor 36, the steam thermistor 37 and the inside of the chamber In the thermistor 35, when only the engine thermistor 36 and the steam thermistor 37 are operable, the water amount detection unit 38 controls the water temperature in the water pot 15 and the water temperature based on the detection signals from the engine thermistor 36 and the steam thermistor 37. If the rate of temperature rise in the steam passage 31 is detected, the amount of water in the water pot 15 can be determined.

  FIG. 5 shows a flow chart of the pot water amount detection processing operation which is executed based on the detection signal from the engine thermistor 36 and the detection signal from the steam thermistor 37 under the control of the water amount detector 38. In this case, the water amount in the pot is detected when the temperature detected by the initial engine thermistor 36 is low (that is, when the pot heater 16 is switched from OFF to ON at the start of cooking). If the time to reach the preset temperature is later than the first specified time, it is determined that the water pot 15 is full. In addition, when the time to reach the set temperature of the temperature detected by the steam thermistor 37 is faster than the first specified time and later than the second specified time shorter than the first specified time, It is determined that the amount of water in the pot 15 is medium. Further, when the time until the set temperature of the temperature detected by the steam thermistor 37 is faster than the second specified time, it is determined that the water pot 15 is in a drought state. Hereinafter, the pot water amount detection processing operation will be described in detail with reference to FIG.

  In steps S21 to S24, it is determined whether or not the initial temperature of the water temperature in the water pot 15 is a high temperature of 90 ° C. or higher in the same manner as in steps S1 to S4 in the pot water amount detection processing operation shown in FIG. When the temperature is high, the pot heater 16 is turned off once. When it is determined that the preset cooling time of 180 seconds has elapsed, the pot heater 16 is turned on and a low temperature start is started.

  In step S25, it is determined whether or not the elapsed time after the low temperature start has reached a first specified time 360 seconds that is specified in advance in order to determine that the amount of water in the water pot 15 is large. As a result, if the first specified time has not been reached, the process proceeds to step S26, and if it has reached, the process proceeds to step S31.

  As described above, when the amount of water in the water pot 15 is full, the steam starts to be supplied from the water pot 15 to the steam passage 31 approximately 360 seconds (6 minutes) after the low temperature start. Therefore, the first specified time for determining that the amount of water in the water pot 15 is large in step S25 is set to 360 sec (6 minutes) after the low temperature start.

  In step S26, the gas temperature in the steam passage 31 is detected based on the detection signal from the steam thermistor 37. In step S27, it is determined whether or not the detected temperature of the steam thermistor 37 has become a high temperature equal to or higher than the set temperature of 60 ° C. As a result, if the temperature is equal to or higher than the set temperature, the process proceeds to step S28, and if the temperature is lower than the set temperature, the process returns to step S25.

  Here, when the water temperature in the water pot 15 reaches a high temperature of approximately 100 ° C., steam is supplied to the steam passage 31 and the gas temperature in the steam passage 31 becomes approximately 60 ° C. or higher. Therefore, in step S27, the set temperature for determining that the temperature of the steam thermistor 37 is high is set to 60 ° C.

  In step S28, it is determined whether or not the elapsed time after the low temperature start has reached a second specified time 180 seconds set shorter than the first specified time 360 seconds. As a result, if the second specified time has been reached, the process proceeds to step S29, and if not, the process proceeds to step S30.

  As described above, when the amount of water in the water pot 15 is ½, the steam starts to be supplied from the water pot 15 to the steam passage 31 approximately 180 seconds (3 minutes) after the low temperature start. Therefore, in step S28, the second specified time for determining that the amount of water in the water pot 15 is about 1/2 of the full water level is 180 seconds (3 minutes) after the start of low temperature.

  In step S29, the steam thermistor 37 has elapsed after the low temperature start before reaching the first specified time 360 seconds and after reaching the second specified time 180 seconds set shorter than the first specified time. Since the temperature of the water reaches the set temperature of 60 ° C. or higher, it is determined that the amount of water in the water pot 15 is medium, and the water amount detection processing operation in the pot is terminated. In step S30, since the temperature of the steam thermistor 37 has reached the set temperature of 60 ° C. or more before the elapsed time after the low temperature start reaches the second specified time of 180 seconds, it is determined that the amount of water in the water pot 15 is small. The After that, the pot water amount detection processing operation is terminated.

  In step S31, since the first specified time of 360 seconds has elapsed before the temperature of the steam thermistor 37 reaches the set temperature of 60 ° C., it is determined that the amount of water in the water pot 15 is large. After that, the pot water amount detection processing operation is terminated.

  In step S32 to step S39, since it is a low temperature start, whether or not the pot heater 16 is turned on and the elapsed time after the low temperature start has reached the first specified time 360 sec as in steps S24 to S31. If not, the temperature of the steam thermistor 37 (that is, the gas temperature in the steam passage 31) is detected, and it is determined whether or not the temperature of the steam thermistor 37 has reached the set temperature 60 ° C. or more. If the temperature is equal to or higher than the temperature, it is determined whether or not the elapsed time after the low temperature start has reached the second specified time of 180 seconds, and if it has reached, the water amount in the water pot 15 is determined to be medium, and the water amount detection processing operation in the pot On the other hand, if not, it is determined that the amount of water in the water pot 15 is small, and the pot water amount detection processing operation is ended. On the other hand, when the first specified time of 360 seconds elapses before the temperature of the steam thermistor 37 reaches the set temperature of 60 ° C. or higher, it is determined that the amount of water in the water pot 15 is large, and the water amount detection processing operation in the pot Is terminated.

  As described above, when the engine thermistor 36 and the steam thermistor 37 for detecting the water temperature in the water pot 15 are provided, or among the engine thermistor 36, the steam thermistor 37, and the internal thermistor 35, the engine thermistor 36 and When only the steam thermistor 37 is in an operable state, the temperature of the steam thermistor 37 is not less than the set temperature of 60 ° C. or more at the time of the low temperature start or the low temperature start state. When the elapsed time reaches the first specified time 360 sec, it is determined that the amount of water in the water pot 15 is large. On the other hand, the elapsed time after the low temperature start is before the first specified time 360 sec, and after the second specified time 180 sec set shorter than the first specified time, the steam thermistor 37. When the temperature of the water reaches the set temperature of 60 ° C. or higher, it is determined that the amount of water in the water pot 15 is medium. Further, if the temperature of the steam thermistor 37 reaches the set temperature of 60 ° C. or more before the elapsed time after the low temperature start reaches the second specified time of 180 seconds, it is determined that the amount of water in the water pot 15 is small. I am doing so.

  Therefore, in a pot-type steam generator that does not use a water tank, the amount of water in the water pot 15 can be detected without using the electrode-type water level sensor.

  Further, the amount of water in the water pot 15 is determined based on the detected temperature from the steam thermistor 37 that detects the gas temperature in the steam passage 31 to which the water vapor generated in the water pot 15 is supplied. Therefore, it is possible to more reliably capture the generation of water vapor from the water pot 15.

  6 to 8 show the inside of the pot that is executed based on the detection signal from the engine thermistor 36 and the detection signal from the in-compartment thermistor 35 as the in-compartment temperature detection unit under the control of the water amount detection unit 38. The flowchart of water quantity detection processing operation is shown. In this case, the water amount in the pot is detected when the temperature detected by the initial engine thermistor 36 is low (that is, when the pot heater 16 is switched from OFF to ON at the start of cooking). When the time to reach the preset temperature set in advance is later than the first specified time, it is determined that the water pot 15 is full. Further, when the time to reach the set temperature detected by the engine thermistor 36 is faster than the first specified time and later than the second specified time shorter than the first specified time, It is determined that the amount of water in the water pot 15 is medium. When the time until the set temperature of the detected temperature by the engine thermistor 36 is faster than the second specified time, it is determined that the water pot 15 is in a drought state. Hereinafter, the water amount detection processing operation in the pot will be described in detail with reference to FIGS.

  In step S41, based on the detection signal from the internal thermistor 35, it is determined whether or not the initial temperature of the gas temperature in the heating chamber 10 is a high temperature of 70 ° C. or higher. As a result, if the temperature is high, the process proceeds to step S42, and if not, the process proceeds to step S61. This step is a step for determining whether or not the operation is a continuous operation in which cooking is performed continuously. Therefore, the discrimination temperature in this step may be, for example, the minimum temperature “70 ° C.” or higher in the heating chamber 10 during continuous operation. If it is not during continuous operation, the process proceeds to step SS61.

  In step S42, based on the detection signal from the engine thermistor 36, it is determined whether or not the initial temperature of the water temperature in the water pot 15 is a high temperature of 90 ° C. or higher. As a result, if the temperature is high (that is, if it is a high temperature start), the process proceeds to step S43; otherwise (that is, if it is a low temperature start), the process proceeds to step S53.

  In step S43 to step S48 and step S52, the pot heater 16 is turned off once in the same manner as in steps S2 to S7 and step S9 in the pot water amount detection processing operation shown in FIG. When it is determined that 180 seconds have elapsed, the pot heater 16 is turned on to shift to a low temperature start, and it is determined whether or not the elapsed time after the low temperature start has reached the first specified time of 300 seconds. If not, the engine thermistor The temperature of 36 (that is, the water temperature in the water pot 15) is detected, and it is determined whether or not the temperature of the engine thermistor 36 is equal to or higher than the set temperature 90 ° C. Otherwise, the process returns to step S46. On the other hand, if the temperature of the engine thermistor 36 reaches the first specified time 300 seconds before reaching the set temperature, it is determined that the amount of water in the water pot 15 is large, and the pot water amount detection processing operation is terminated.

  In step S49, it is determined whether or not the elapsed time after the low temperature start has reached a second specified time of 180 seconds set shorter than the first specified time of 300 seconds. As a result, if the second specified time has been reached, the process proceeds to step S50, and if not, the process proceeds to step S51.

  When the amount of water in the water pot 15 is full, steam is generated in the water pot 15 approximately 360 seconds (6 minutes) after the start of low temperature. On the other hand, when the amount of water in the water pot 15 is ½ that when the water pot is full, steam starts to be generated in the water pot 15 approximately 180 seconds (3 minutes) after the low temperature start. Therefore, in step S49, the second specified time for determining that the amount of water in the water pot 15 is about 1/2 of the full water level is 180 seconds (3 minutes) after the start of low temperature.

  In step S50, the elapsed time after the low temperature start is before the first specified time 300sec, and after the second specified time 180sec set shorter than the first specified time, the engine thermistor 36 is reached. Since the temperature of the water has reached the set temperature of 90 ° C. or higher, it is determined that the amount of water in the water pot 15 is medium, and the pot water amount detection processing operation is terminated. In step S51, since the temperature of the engine thermistor 36 has reached the set temperature 90 ° C. or more before the elapsed time after the low temperature start reaches the second specified time 180 seconds, it is determined that the amount of water in the water pot 15 is small. The After that, the pot water amount detection processing operation is terminated.

  Since it is a low temperature start in steps S53 to S60, the pot heater 16 is turned on in the same manner as in the above steps S45 to S52, and whether or not the elapsed time after the low temperature start has reached the first specified time of 300 sec. If not, the temperature of the engine thermistor 36 (that is, the water temperature in the water pot 15) is detected, and it is determined whether or not the temperature of the engine thermistor 36 has reached the set temperature 90 ° C. or more. If it is above, it is determined whether or not the elapsed time after the low temperature start has reached the second specified time 180 sec. If it has reached, the water amount in the water pot 15 is determined to be medium, and the water amount detection processing operation in the pot is performed. On the other hand, if not reached, it is determined that the amount of water in the water pot 15 is small, and the pot water amount detection processing operation is ended. On the other hand, when the first specified time of 300 seconds elapses before the temperature of the engine thermistor reaches the set temperature of 90 ° C. or more, it is determined that the amount of water in the water pot 15 is large, and the water amount detection processing operation in the pot Is terminated.

  As described above, if it is determined in step S41 that it is not during continuous operation, the process proceeds to step SS61. Here, in the case of non-continuous operation, the pot heater 16 is turned off when one heating cooking is completed. Therefore, the state of the steam generator 12 at the start of cooking when not continuously operated is the same as that at the low temperature start. Therefore, the processing after step SS61 in the case of non-continuous operation may be the same processing as in the low temperature start.

  Therefore, in steps S61 to S68, whether or not the pot heater 16 is turned on and the elapsed time after the low temperature start has reached the first specified time of 300 sec in the same manner as the above steps S45 to S52 at the low temperature start. If not, the temperature of the engine thermistor 36 (that is, the water temperature in the water pot 15) is detected, and it is determined whether or not the temperature of the engine thermistor 36 has reached the set temperature 90 ° C. or more. If the temperature is equal to or higher than the temperature, it is determined whether or not the elapsed time after the low temperature start has reached the second specified time of 180 seconds, and if it has reached, the water amount in the water pot 15 is determined to be medium, and the water amount detection processing operation in the pot On the other hand, if not, it is determined that the amount of water in the water pot 15 is small, and the pot water amount detection processing operation is ended. On the other hand, when the first specified time of 300 seconds elapses before the temperature of the engine thermistor reaches the set temperature of 90 ° C. or more, it is determined that the amount of water in the water pot 15 is large, and the water amount detection processing operation in the pot Is terminated.

  As described above, when the engine thermistor 36 and the internal thermistor 35 for detecting the water temperature in the water pot 15 are provided, or the engine thermistor 36 among the engine thermistor 36, the steam thermistor 37 and the internal thermistor 35. When only the internal thermistor 35 is in an operable state, the temperature of the engine thermistor 36 becomes low before the set temperature of 90 ° C. or higher when the low temperature start or the low temperature start state is reached. When the elapsed time after the start reaches the first specified time of 300 seconds, it is determined that the amount of water in the water pot 15 is large. On the other hand, the elapsed time after the low temperature start is before the first specified time 300 seconds, and after the second specified time 180 seconds set shorter than the first specified time, the engine thermistor 36 When the temperature is equal to or higher than the set temperature 90 ° C., it is determined that the amount of water in the water pot 15 is medium. Further, if the temperature of the engine thermistor 36 reaches the set temperature 90 ° C. or more before the elapsed time after the low temperature start reaches the second specified time 180 seconds, it is determined that the amount of water in the water pot 15 is small. I am doing so.

  Therefore, in a pot-type steam generator that does not use a water tank, the amount of water in the water pot 15 can be detected without using the electrode-type water level sensor.

  Further, based on the detection signal from the internal thermistor 35 that detects the gas temperature in the heating chamber 10, it is determined whether or not the operation is continuous. Therefore, the pot water amount detection processing operation can be performed separately for the case of continuous operation and the case of not being continuous, and the amount of water in the pot can be detected even in the case of continuous operation.

  Here, the specified time of 300 sec and the set temperature of 90 ° C. in FIG. 4 are set based on the change with time of the water temperature when the amount of water in the water pot 15 is full. Therefore, “large” means that the amount of water in the water pot 15 in FIG. 4 of the present embodiment is “full”, and “small” means “less than full”. Further, the first specified time 360 sec, the set temperature 60 ° C. and the second specified time 180 sec in FIG. 5, the first specified time 300 sec, the set temperature 90 ° C. and the second specified time 180 sec in FIGS. Is set based on changes over time in the water temperature and the steam temperature in the steam passage 31 when the amount of water in the water pot 15 is full or ½. Accordingly, the amount of water in the water pot 15 in FIGS. 5 to 8 of the present embodiment is “full”, and “medium” is “1/2 or more and less than full”. Therefore, “less” means “less than 1/2”.

  In the example shown in FIG. 4, since the specified time for determining the amount of water in the water pot 15 is set to only “300 sec” for determining whether the water is full, the amount of water in the water pot 15 is set. It can be determined only in two stages, “high = full” and “low = under full”. However, as in the case of the examples shown in FIGS. 6 to 8, the specified time for determining the amount of water in the water pot 15 is “300 sec” for determining whether or not the water is full, and is 1/2 or more of the full If it is set to “300 sec” for determining whether or not, the amount of water in the water pot 15 can be determined in three stages: “large”, “medium” and “low”. Furthermore, if the specified time for determining the amount of water in the water pot 15 is set to 4 or more according to the amount of water in the water pot 15, the amount of water in the water pot 15 can be determined in four or more stages. The same applies to the case of FIG. 5 using the temperature detected by the steam thermistor 37.

  Further, in the above embodiment, when it is determined that the “specified cooling time” has elapsed in step S3 in FIG. 4, step S23 in FIG. 5, and step S44 in FIG. 6, the pot heater 16 is turned on in the next step. I have to. However, the present invention is not limited to this, and when it is determined based on the temperature of the engine thermistor 36 that the water temperature in the water pot 15 has reached room temperature, the pot heater 16 is turned on in the next step. But it does n’t matter.

  In addition, the specified time, the set temperature, the first specified time, and the second specified time in the above embodiment are merely examples, and may be set to different values depending on the volume of the water pot 15 and the capacity of the pot heater 16. It does n’t matter.

  In the above embodiment, the elapsed time until the water temperature in the water pot 15 reaches the set temperature 90 ° C. is used as an indicator of the rate of increase in the water temperature of the water pot 15, and the water pot is compared with the specified time. The amount of water in 15 is determined. However, by comparing the water temperature in the water pot 15 after the elapse of a preset set time with the preset temperature set according to the amount of water in the water pot 15 as an index of the rate of increase in the water temperature of the water pot 15 The amount of water in the water pot 15 may be determined.

  Moreover, in the said embodiment, the case where this invention is applied to the pot type steam generator which does not use a water tank is demonstrated to the example. However, the present invention is not limited to this and may be applied to a steam generator using a water tank.

1 ... Cabinet,
3, 4, 5 ... IH heater,
9 ... roaster,
12 ... steam generator,
15 ... water pot,
16 ... pot heater,
20 ... Upper heater,
21 ... Lower heater,
22 ... Upper heater room,
23 ... Lower heater room,
31 ... Steam passage,
32 ... steam supply hole,
35 ... Thermistor in the cabinet,
36 ... Engine thermistor,
37 ... Steam thermistor,
38 ... Water quantity detection unit,
39: Timer.

Claims (8)

A water pot for storing water for steam generation;
A pot heater for heating the water pot to generate water vapor;
A water temperature detector that detects a temperature corresponding to the water temperature in the water pot and outputs a detection signal representing the detected temperature;
Based on the detection signal from the water temperature detection unit, the rate of increase of the water temperature in the water pot is determined, and the rate of increase of the obtained water temperature and a set rate of increase set in advance according to the amount of water in the water pot, A water amount detection device comprising: a water amount detection unit configured to detect the amount of water in the water pot based on the comparison result. The water amount detection device according to claim 1,
The water amount detection unit can control the on / off of the pot heater,
A water temperature detection unit in the pot that detects the water temperature in the water pot and outputs a detection signal representing the detected temperature,
The water amount detection unit has a first preset temperature at which an initial temperature of the water temperature in the water pot based on a detection signal from the water temperature detection unit in the pot is a temperature at which water vapor starts to be generated from a preset water surface in the pot. In the case of the above, the pot heater is once turned off, and the pot heater is turned on after the water temperature in the water pot reaches room temperature, and the rate of increase in the water temperature in the water pot is obtained. A water amount detection device characterized by that. In the water amount detection device according to claim 1 or 2,
The water volume detector
Including a timekeeping section for measuring the elapsed time since the pot heater was turned on,
The rate of increase of the water temperature in the water pot is to measure the elapsed time from when the pot heater is turned on until the temperature corresponding to the water temperature in the water pot reaches a preset temperature. Sought by,
The set increase rate is an elapsed time until a temperature corresponding to the water temperature in the water pot is preset according to the amount of water in the water pot until the set temperature is reached. . In the water amount detection device according to claim 1 or 2,
The water volume detector
Including a timekeeping section for measuring the elapsed time since the pot heater was turned on,
The rate of increase of the water temperature in the water pot is the temperature corresponding to the water temperature in the water pot when the elapsed time counted by the time measuring unit reaches a preset set elapsed time. Sought by detecting,
The set increase rate corresponds to the water temperature in the water pot that is set in advance according to the amount of water in the water pot, and the elapsed time from when the pot heater is turned on becomes the set elapsed time. A water amount detection device characterized by temperature. In the water amount detection device according to any one of claims 1 to 4,
The water amount detection device, wherein the water temperature detection unit is a water temperature detection unit in the pot that detects a water temperature in the water pot. In the water amount detection device according to any one of claims 1 to 4,
One end is connected to the water pot, and includes a steam passage to which water vapor generated in the water pot is supplied.
The water amount detection device according to claim 1, wherein the water temperature detection unit is a gas temperature detection unit in the steam passage that detects a gas temperature in the steam passage. The water amount detection device according to any one of claims 1 to 6,
A steam generator including the water pot and the pot heater of the water amount detection device;
A steam cooker, comprising: a heating chamber in which steam generated by the water pot is supplied and cooking is performed using heat from the steam as a heat source. The steam cooker according to claim 7, wherein
The water amount detection unit in the water amount detection device is capable of controlling on / off of the pot heater,
An internal temperature detector that detects the gas temperature in the heating chamber and outputs a detection signal representing the detected temperature,
The water amount detection unit is configured such that the initial temperature of the gas temperature in the heating chamber based on the detection signal from the internal temperature detection unit is a preset minimum temperature in the heating chamber during continuous operation in which continuous cooking is performed. When the temperature is equal to or higher than the second set temperature, the pot heater is turned off, the pot heater is turned on after the water temperature in the water pot reaches room temperature, and the rate of increase in the water temperature in the water pot is determined. A steam cooker characterized by what is required.

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