JP2007296028A - Electric kettle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric kettle capable of avoiding cavitation in the early starting stage of electric hot-water supply action of an electric hot-water supply pump when performing a hot-water supply by driving the electric hot-water supply pump, and performing a stable electric hot-water supply. <P>SOLUTION: The electric kettle is equipped with the electric hot-water supply pump and an electric hot-water supply pump control means for controlling the driving state of the electric hot-water supply pump. The electric hot-water supply pump control means restricts and controls a hot-water supply volume to be smaller than that in the normal time during a prescribed period at the early starting stage of the electric hot-water supply action, and by it, cavitation of the electric hot-water supply pump hardly occurs even if many bubbles are contained in the hot-water immediately after termination of hot-water boiling so that stable electric hot-water supply can be achieved. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric pot, and more particularly to the structure of an electric pot equipped with an electric hot water supply pump.

  In general, in an electric pot, water stored in an inner container is heated and boiled by a heating means such as an electric heater and then stored at a predetermined temperature.

  And in such an electric pot, when an electric hot water supply pump is provided and electric hot water supply is possible, for example, as long as the hot water switch for operating the electric hot water pump is pressed, continuous hot water supply is pressed once and the hot water switch is pressed once. Thus, it is possible to carry out a fixed amount of hot water that has been set in advance, which is very convenient (see, for example, Patent Document 1).

JP-A-7-163470 (Specification page 1-4, FIG. 1-5)

  However, when the electric hot water supply method as described above is adopted, for example, for a while immediately after the completion of boiling, the hot water in the electric hot water pump also contains a lot of bubbles, so the electric hot water pump cavitates at the start of hot water supply. Is likely to occur, and there is a problem that stable electric hot water supply cannot be performed.

  In this case, press the hot water supply key within a predetermined time to rotate the electric hot water pump, stop the electric hot water pump, return the bubbles in the electric hot water pump into the inner container, and then press the hot water key again to turn on the electric hot water. Although it is possible to perform normal hot water supply, it is troublesome to perform such an operation manually.

  The present invention has been made to solve such a problem. In the case where the electric hot water supply pump control means for controlling the driving state of the electric hot water supply pump drives the electric hot water supply pump to supply hot water, An object of the present invention is to provide an electric kettle that enables stable electric hot water supply by limiting the amount of hot water supply within a predetermined time at the beginning of the electric hot water supply operation of the electric hot water supply pump.

  In order to achieve the above object, the present invention comprises the following problem solving means.

(1) First Problem Solving Means The first problem solving means of the present invention includes an inner container, a heating means for heating the water in the inner container, and the heating means to operate the inner container. Heating control means for boiling water by boiling water, and then keeping the temperature at a predetermined temperature, an electric hot water pump for supplying hot water in the inner container to the outside through a hot water supply passage, and driving of the electric hot water pump In an electric pot comprising an electric hot water supply pump control means for controlling the state, when the electric hot water supply pump performs the electric hot water supply by driving the electric hot water supply pump, at the beginning of the electric hot water supply operation, It is characterized in that a limited amount of hot water supply is controlled within a predetermined time to be smaller than normal.

  According to such a configuration, at the beginning of the electric hot water supply operation, the hot water supply amount is limited to be smaller than the normal time within a predetermined time, so that the electric hot water pump is temporarily stopped including a temporary stop in the limited state. Even if bubbles are included in the hot water in the electric hot water supply pump, only the bubbles are effectively returned to the inner container.

  As a result, cavitation of the conventional electric hot water supply pump hardly occurs, and stable electric hot water supply becomes possible.

(2) Second Problem Solving Means According to a second problem solving means of the present invention, in the configuration of the first problem solving means, the hot water supply amount limiting control at the beginning of electric hot water supply is performed within a predetermined time after the completion of boiling. It is characterized by being performed only for hot water supply operation.

  Even when the hot water is heated, the cavitation of the electric hot water supply pump does not occur when a predetermined time (a time sufficient for the bubbles to disappear) elapses after the hot water is finished.

  Therefore, the hot water supply amount restriction control at the beginning of the electric hot water supply is performed only for the electric hot water supply operation within a predetermined time after the completion of the hot water supply, and thereafter, a sufficient amount of hot water can be supplied.

(3) Third Problem Solving Means According to a third problem solving means of the present invention, in the configuration of the first or second problem solving means, the hot water supply amount restriction control intermittently drives the electric hot water supply pump. It is a feature that is made by.

  Although the electric hot water supply amount can be limited by driving the electric hot water supply pump by several methods, one method can be realized by intermittently driving the electric hot water supply pump ON and OFF.

(4) Fourth Problem Solving Means According to a fourth problem solving means of the present invention, in the configuration of the first or second problem solving means, the hot water supply amount limiting control is performed by setting the electric hot water pump to a voltage lower than normal. It is characterized by being made by driving with.

  The electric hot water supply amount can be limited by driving the electric hot water supply pump by several methods, but as one method, it can be realized by slowly rotating the electric hot water supply pump at a voltage lower than normal. Can do.

  As a result of the above, according to the electric pot of the present invention, stable electric hot water supply can be realized without performing troublesome manual operation of the hot water supply key even during hot water supply immediately after the end of boiling.

  Hereinafter, the configuration and operation of an electric pot according to the best embodiment of the present invention will be described with reference to the accompanying drawings.

(Configuration of the electric pot body)
First, FIGS. 1 to 3 show the configuration of the main body and the main part of the electric pot according to the best mode of the present invention.

  As shown in FIGS. 1 and 2, the electric pot includes a container body 1 having an inner container 3 for storing hot water, a lid body 2 that opens and closes an upper opening of the container body 1, and the inner container 3. Water heater 4A, which is a heating means for heating when boiling water, a heat retaining heater 4B, which is a heating means for heating the inner container 3, and a hot water supply passage for supplying hot water in the inner container 3 to the outside 5 and the flow rate sensor 80 for measuring the hot water flow rate provided in the middle of the hot water supply passage 5 and the hot water in the inner container 3 are sent out through the hot water supply passage 5 in a state where an AC power source is connected. The electric hot water supply pump 6 and an air-type manual hot water supply pump 18 that sends hot water in the inner container 3 to the outside through the hot water supply passage 5 in a state where an AC power source is not connected are configured.

  The said container main body 1 couple | bonds integrally the cylindrical outer case 7 made from a synthetic resin which comprises an outer side surface part, the said inner container 3 which comprises an inner side part, and the said outer case 7 and the inner container 3 on the upper side. It consists of an annular shoulder member 8 made of synthetic resin to be fixed and a dish-shaped bottom member 9 made of synthetic resin that constitutes the bottom surface portion.

  The inner container 3 is composed of a vacuum double structure with high heat retention performance in which a vacuum heat insulating space is provided between a stainless steel bottomed cylindrical inner cylinder 10 and a stainless steel cylindrical outer cylinder 11. In addition, a single plate portion 3a composed only of the bottom surface portion of the inner cylinder 10 except for the outer peripheral portion is formed at the bottom portion. The single plate portion 3a is formed so as to protrude slightly upward. On the lower surface side, the water heater 4A and the heat retaining heater 4B (for example, two sets of heating elements having different wattages are held on the mica plate). A mica heater is attached.

  A small-diameter water supply port 3b having a heat keeping structure is formed at the upper end portion of the inner container 3 by drawing the upper end portion on the inner cylinder 10 side toward the central axis direction. Reference numeral 12 denotes a bottom sensor (hot water temperature sensor) that functions as a hot water temperature detecting means for detecting the temperature of the inner container 3 (in other words, the temperature of hot water in the inner container 3), and includes a thermistor. . Further, reference numeral 13 denotes a convex full water level display portion that displays the full water level of the inner container 3.

  The lid 2 includes a synthetic resin upper plate 14 and a synthetic resin lower plate 15 having an outer peripheral edge coupled to the upper plate 14, and is provided at the rear portion of the shoulder member 8. The hinge receiver 16 is supported by a hinge pin 17 so that it can be opened and closed in a vertical direction and is detachable.

  The lid 2 is provided with an air-type manual hot water supply pump 18 that is compressed by a manual pressing operation so that hot water can be supplied to the outside through the hot water supply passage 5 even when an AC power source is not connected. It is installed. The manual hot water supply pump 18 is of a bellows type disposed in a cylindrical portion 19 formed at a substantially central portion of the lid 2, and has a bellows structure via a pressing cover 20A and a pressing plate 20B. By pressing the bellows 20C downward, the pressurized air 20D in the bellows 20C is blown into the inner container 3 through the air blowing port, and the hot water in the inner container 3 is supplied with hot water by the pressure of the pressurized air. It is pushed out through the passage 5. Further, 20E is a restoring spring upward of the bellows 20C, and 15A is a bellows support plate on the lower plate 15 side. Reference numerals 21a to 21d are steam discharge passages of the lid body 2 that are in communication with each other from the lower side to the upper side. It is a valve.

  A metal inner cover member 23 is fixed to the lower surface of the lower plate 15 in the lid 2, and the inner container 3 is attached to the outer peripheral edge of the inner cover member 23 when the lid 2 is closed. A heat-resistant rubber seal packing 24 is provided in pressure contact with the upper surface of the water supply port 3b.

  At the lower position of the inner container 3 on the upstream end side of the hot water supply passage 5, a DC type electric hot water pump 6 is disposed through an inner container 3 side hot water introduction cylinder 6a and a hot water supply pump side hot water inlet 6b. In this hot water supply passage 5, hot water sucked from the hot water inlet 6 b through the hot water inlet cylinder 6 a is discharged from the discharge port 6 c by the pumping action of the electric hot water supply pump 6, After passing through the straight pipe portion 5b, it passes through the flow rate detection passage in the flow rate sensor 80 and is led to the hot water pouring outlet 5d from the overturn stop water valve side connecting pipe 5c.

  Further, reference numeral 35 denotes an operation panel unit provided with operation surfaces of various switches described later and a display unit of a liquid crystal display device, and 51a represents a microcomputer control unit 60 described later and various switches 38 to 41, 42, 43a, 43b. , 44, a microcomputer substrate having a drive unit for a crystal display device, 51 is a support member for the liquid crystal display device 47, 50 is a drive circuit for the electric hot water supply pump 6, a heating heater 4A, a heating control circuit for the heat retaining heater 4B, It is a power supply board provided with a stabilized DC power supply circuit and the like.

  The operation panel 35 includes a hot water supply switch 38, a hot water supply lock release switch 39, a hot water supply lock release display LED 39a, a re-boiling switch 40, an energy saving course selection / timer switch 41, a metering cup switch 42 for selecting a quantitative hot water supply mode, and a heat insulation. There are provided selection switches 43a and 43b, a magic bottle thermal insulation dedicated switch 44, a reboiling display LED 45, a thermal insulation operation display LED 46, a liquid crystal display device 47 (liquid crystal display surface 47a), and the like.

  In this embodiment, the heat retention selection switches 43a and 43b have two functions: a heat retention mode selection switch for selecting a normal heat retention mode by a screening operation, and a setting heat retention temperature up setting switch and a down setting switch. Also serves as.

  The liquid crystal display device 47 is provided with a liquid crystal display surface 47a such as time / time / hot water temperature setting temperature / magic bottle heat retention so that various necessary information can be displayed with low power consumption. It has become.

  In addition, this electric hot water supply type electric pot continuously drives the electric hot water supply pump 6 to supply hot water as long as the hot water supply switch 38 is continuously pressed on condition that the lock release switch 39 is turned on. The continuous hot water supply mode that can be dispensed, and the electric release when the predetermined amount of hot water set in advance by the measuring cup switch is dispensed even if the lock release switch 39 is turned on and the hot water switch 38 is kept pressed. The hot water supply pump 6 is configured to have two hot water supply modes, that is, a fixed hot water supply mode in which hot water supply is locked while the hot water supply pump 6 is stopped.

  In the case of the present embodiment, in any of the hot water supply modes, at least at the beginning of the electric hot water supply operation immediately after the completion of the boiling through the boiling operation, the electric hot water supply pump 6 within a predetermined time is intermittently operated. By driving, the hot water supply amount is limited to a smaller value than normal, and intermittent rotation of the electric hot water supply pump in the hot water supply restriction state returns the bubbles in the electric hot water supply pump to the inner container, preventing cavitation. Thus, stable electric hot water supply is made possible.

  The flow rate sensor 80 used for controlling the electric hot water supply pump 6 comprises, for example, as shown in FIG. 3, a spiral rotary screw blade 82 provided on the outer periphery of a rotary support shaft 81, A tube made of a transparent body is provided on the outer periphery of the hot water supply passage 5 while being fitted and fixed in the middle of the straight pipe portion 5b of the hot water supply passage 5 through a fitting tube 83, and the outer peripheral portion of the hot water passage 5 is liquid-tightly covered with a silicon elastic body 89. The lower end portion 84a of the channel-shaped passage forming member 84 is fitted. Further, the upper end portion 84b of the passage forming member 84 is butted against the lower end of the fall stop water valve side connecting pipe 5c, and a sleeve 88 is fitted to the outer periphery of the butting portion to be connected and fixed in a sealed state.

  Further, an apparatus support flange 84c is provided on the outer periphery on the lower side of the passage forming member 84, and a double wall of a first cylindrical wall 85a having a small diameter and a second cylindrical wall 85b having a large diameter is provided on the upper portion thereof. An umbrella-shaped device cover 85 having a cylindrical wall structure is fitted and fixed. A device substrate 86 is attached using the first cylindrical wall 85a, and a light emitting portion 87a and a light receiving portion are disposed at both front and rear positions facing each other across the transparent passage forming member 84 on the device substrate 86. 87b are installed with their optical axes aligned with each other. The optical axes of the light emitting portion 87a and the light receiving portion 87b have a radius greater than the rotational center axis position so that the optical axis is located through the gap between the upper and lower blades of the spiral rotating screw blade 82 in the passage forming member 84. It is installed at a predetermined position outward in the direction.

  Therefore, when the electric hot water supply pump 6 is driven and hot water passes through the hot water flow passage in the passage forming member 84 from the lower side to the upper side through the straight pipe portion 5b, the helical rotary screw blade 82 is thereby moved. However, the optical axis between the light emitting part 87a and the light receiving part 87b is interrupted every half rotation, and the light receiving part 87b outputs a predetermined number N of output signals corresponding to the rotation speed within the unit time. Is output. The number N of output signals eventually represents the amount of hot water supplied by the electric hot water supply pump 6.

(Configuration of control circuit)
Next, FIG. 4 is an electric circuit diagram showing the configuration of the control circuit section in the electric pot body having the above configuration.

  In FIG. 4, reference numeral 52 is an AC power source, 4A is a hot water heater, 4B is a heat retaining heater, 60 is a microcomputer control unit, 63 is a zero cross detection circuit for power supply voltage, 64 is a smoothing capacitor, 6 is an electric hot water supply pump (and pump drive). ), RS is a power switch (relay switch) for operating the water heater 4A, RL is a power relay for driving the power switch RS (relay drive circuit such as a relay coil), 53 is a triac for operating the heat retaining heater 4B, 57 is A transistor for driving the triac 53, 61 is a hot water prevention circuit of the electric hot water supply pump 6, and 62 is a hot water supply notification circuit for notifying the hot water supply condition on condition that the hot water supply switch 38 is turned on.

  Reference numeral 65 denotes a chargeable large-capacity electric double layer capacitor that is used as a DC constant voltage power source for operation of a microcomputer or the like instead of the power source from the constant voltage power source during the heat insulation of the magic bottle. Along with the switch circuit 66, the power supply relay RL is connected in parallel (in the figure, one is provided, but two can be provided in parallel).

  Reference numeral 67 denotes a discharge voltage detection circuit which detects that the voltage of the electric double layer capacitor 65 has become equal to or lower than a specified value and inputs the detected voltage to the microcomputer control unit 60.

  For example, when the hot water heater ON signal is output from the microcomputer control unit 60, the hot water heater 4A is driven by first operating the power relay RL and correspondingly turning on the power switch RS.

  Further, when the warming heater ON signal is output from the microcomputer control unit 60, the warming heater 4B is driven by turning on the transistor 57 and triggering the triac 53.

  Furthermore, when the hot water supply switch 38 inserted in the ground side line of the electric hot water supply pump 6 is turned on, an ON signal of the hot water supply switch 38 is sent to the microcomputer control unit 60 via the hot water supply notification circuit 62. The microcomputer controller 60 outputs a pulse voltage signal having a predetermined duty ratio, and is appropriately driven to rotate at a predetermined duty ratio.

  The electric hot water supply pump 6 intermittently drives the electric hot water supply pump 6 within a predetermined time under the control of the microcomputer control unit 60 at least at the beginning of the electric hot water supply operation immediately after the completion of the boiling after the boiling operation. Thus, the hot water supply amount is limited to be smaller than that in the normal state, and only the bubbles in the electric hot water supply pump are effectively returned to the inner container by the intermittent rotation of the electric hot water supply pump 6 in the hot water supply amount limited state. Thus, cavitation of the conventional electric hot water supply pump is prevented, and stable electric hot water supply becomes possible.

  The microcomputer controller 60 is supplied with a predetermined constant voltage (not shown) via a constant voltage power source (original operating power source) (not shown).

  Further, the microcomputer control unit 60 further includes various display units such as a liquid crystal display unit 47, a reboil display LED 44, a heat insulation operation display LED 45, a hot water supply unlock display LED 46, a hot water switch 38, a reboil switch 40, a hot water supply Various operation units (switch circuit) such as an unlock switch 39, energy saving course selection / timer switch 41, measuring cup switch 42, heat retention selection switches 43a and 43b, and a magic bottle heat retention and warming switch 44, temperature detection means 12, flow sensor Various sensor units (sensor circuit) such as 80, a first clock frequency oscillator (4 MHz) 58 for operating the microcomputer during normal time, a second clock frequency oscillator for operating the microcomputer during thermal insulation (when saving energy) ( 32.768 KHz) 59 etc. are connected via each input / output port. That.

  Further, in the above circuit, the electric double layer capacitor 65 is charged using the original chopper power supply circuit when the heat retaining heater 4B is turned on during the boiling operation and the heat retaining operation, etc., while the chopper is turned off when the heat retaining heater 4B is turned off. The power supply circuit is stopped by microcomputer control, and the microcomputer and the display unit are operated by the discharge charge of the electric double layer capacitor 65, thereby saving as much standby power as possible when the balance is kept warm. I have to. As an example, the electric double layer capacitor 65 has a withstand voltage of 5.5V (MAX), and in order to increase the withstand voltage, series connection may be performed. MAX)).

(Hot water supply restriction control)
By the way, in the case of an electric kettle adopting the electric hot water supply structure as described above, for example, for a while immediately after the completion of boiling, the hot water in the electric hot water supply pump contains a lot of bubbles. There is a problem that cavitation tends to occur in the pump, and stable electric hot water supply cannot be performed.

  In this case, after the electric hot water supply pump 6 is rotated by pressing the hot water supply switch (hot water supply key) 38 within a predetermined time, the electric hot water supply pump 6 is stopped and the foam in the electric hot water supply pump 6 is returned to the inner container 3. When the hot water supply switch 38 is pressed again to perform electric hot water supply, normal hot water supply can be performed. However, it is troublesome to perform such an operation manually.

  In the present embodiment, in order to solve such a problem, the microcomputer control unit 60 as the electric hot water supply pump control means for controlling the driving state of the electric hot water supply pump 6 corresponds to the ON operation of the hot water supply switch 38. When the hot water supply is performed by driving the electric hot water supply pump 6 immediately after the completion of the boiling, even if the electric hot water supply operation by the electric hot water supply pump 6 is started within a predetermined time after that, The electric hot water supply pump 6 is intermittently driven (ON, OFF) so that the amount of hot water supply is limited to be smaller than normal, thereby effectively returning the bubbles in the electric hot water supply pump 6 into the inner container 3. Prevents cavitation and enables stable electric hot water supply.

  The control is started on the condition that boiling (water boiling) has been completed, as shown in the flowchart of FIG. 5, for example.

Therefore, first, performs a boiling end determination in step S ₁ in the flowchart of FIG. 5, the process proceeds to step S ₂ in the state of NO determination before the end Tou boiling, cavitation for executing the hot water supply amount limiting control after boiling completion sets the protection flag to 1 (execution), it turns OFF the electric hot water pump 6 in step S _3.

On the other hand determines then boiling etc. is completed and YES determination is made in step S _1, the hot water supply switch 38 then proceeds to step S ₄ is whether the ON operation. As a result, while when the NO to leave the electric hot water pump 6 OFF shifts to step S ₃ described above, the routine proceeds to step S ₅ when YES, the value of the anti-cavitation flag is 1 (hot water supply amount limiting execution) It is determined whether or not it is set.

As a result, when NO, the hot water supply amount limiting control operation of steps S _{6 to} S ₁₁ is jumped to proceed to step S ₁₂ , the electric hot water supply pump 6 is continuously turned on to supply hot water as usual, and step S _{In 13} , the value of the cavitation flag is set to 0 (no hot water supply restriction).

On the other hand, when the value of the cavitation flag of YES is set to 1 is determined in step S _5, first it proceeds to step S _6, the intermittent drive timer for intermittently driving the electric water heater pump 6 Timer together to start the count operation, it turns oN the electric hot water pump 6 at step S _7.

Then, further in step S _8, and determines whether the subsequent set ON intermittent time of 1 second has elapsed until YES, and becomes to YES, similarly in step S ₉ the timer count operation for OFF time count with is started, to OFF OFF intermittent time within 0.6 seconds electric hot water pump 6 set in step S ₁₀ that follows.

Thereafter, in step S _11, whether the OFF interval time 0.6 seconds have elapsed repeatedly determined until YES, and becomes to YES, the process proceeds to step S _12, in turn ON the electric hot water pump 6 drives the electric hot water pump 6, sets the value of cavitation flag to 0 (hot water supply amount restriction not performed) in step S _13.

  According to the configuration as described above, at least at the beginning of the electric hot water supply operation after the completion of boiling after the boiling operation, the amount of hot water supply is limited to be smaller than the normal time within a predetermined time (the electric hot water supply pump 6 Due to the intermittent rotation of the electric hot water supply pump 6 in the same limited state, even if the hot water in the electric hot water supply pump 6 contains bubbles, only the same bubbles are effectively contained in the inner container. 3 is returned.

  As a result, cavitation of the conventional electric hot water supply pump 6 is less likely to occur, and stable electric hot water supply becomes possible.

  In addition, in the above configuration, the hot water supply amount restriction control at the beginning of the electric hot water supply is performed only for the electric hot water supply operation within a predetermined time after the completion of boiling.

  Even when the hot water is heated, cavitation of the electric hot water supply pump does not occur when a predetermined time (a time sufficient for the bubbles to disappear) elapses after the hot water is finished.

  Therefore, the hot water supply amount restriction control at the beginning of the electric hot water supply is performed only in the electric hot water supply operation within a predetermined time after the completion of the hot water supply, and thereafter, a sufficient amount of hot water can be supplied.

  Furthermore, the hot water supply amount restriction control in the above configuration is performed by intermittently driving the electric hot water supply pump 6 as described above.

  Although the electric hot water supply amount by driving the electric hot water supply pump 6 can be limited by several methods, it can be easily realized by intermittently driving the electric hot water supply pump 6 as described above. Can do.

(Best Mode 2)
Next, the flowchart of FIG. 6 shows the contents of the hot water supply amount restriction control of the electric pot according to the second embodiment of the present invention.

  The hot water supply amount restriction control of this embodiment is performed by slowly rotating the hot water supply amount control by the electric hot water supply pump 6 at a voltage lower than normal at the electric hot water supply pump 6. Moreover, it is characterized in that it is driven not after the boiling determination as described above but during the boiling determination.

  The prevention of cavitation by limiting the amount of electric hot water supply by the drive control of the electric hot water supply pump 6 as described above can be performed by several methods, but as one method, the electric hot water supply pump 6 described above is operated at normal time (rated voltage). ), And can be realized by slowly rotating at a lower voltage.

  Further, in that case, cavitation due to the generation of bubbles actually occurs not immediately after boiling, but immediately before boiling. Therefore, the electric hot water supply pump 6 is slowly rotated at a lower voltage than normal during boiling determination. When placed, the bubbles in the electric hot water supply pump 6 are effectively returned to the inner container 3 and cavitation is more effectively prevented.

  That is, as shown in the flowchart of FIG. 6, the control is started on the condition that boiling (hot water) determination is being performed.

Therefore, first, it performs a boiling determination in Step S ₁ of the flow, in the state of NO is not in a boiling determination to OFF the electric hot water pump 6 proceeds to step S _6.

On the other hand, then, starts boiling determination, if YES determination is made in step S _1, the hot water supply switch 38 regardless of whether the ON operation then proceeds to step S _2, the routine proceeds to step S _2, while the oN electric hot water pump 6 to 80% lower low voltage 20% than in the normal, further proceeds to step S _3, determines whether the boiling operation is completed.

As a result, when the NO, the process proceeds to Step S ₆ to jump the timer operation in step S ₄ to S _5, the electric hot water pump 6 to OFF.

On the other hand, when in the boiling or the like YES, first proceeds to step S _4, with a timer is started counting operation of the low voltage drive timer, it determines an elapsed time of the timer in step S _5.

Then, as a result, at the YES has elapsed low voltage set time, and ends the same control by the electric hot water pump 6 to the OFF proceeds to step S _6.

  According to the above configuration, when the electric hot water supply operation is started, the electric hot water supply pump 6 is gently rotated at a voltage smaller than normal during a predetermined time from the boiling determination. Due to the gentle rotation of the electric hot water supply pump 6, even if the hot water in the electric hot water supply pump 6 contains bubbles, only the bubbles are effectively returned to the inner container.

  As a result, cavitation of the conventional electric hot water supply pump does not easily occur, and when hot water supply switch 38 is turned on and hot water supply is started after boiling is completed, stable electric hot water supply becomes possible.

(Other embodiments)
(1) The intermittent control of the electric hot water supply pump 6 according to the first preferred embodiment described above is basically the first control after boiling, and the user temporarily stops the discharge during the same control, and then restarts the operation. Even if the operation is performed, the same control is not performed. This is based on the idea that once the user controls the discharge, the microcomputer performs the same function as the control for stopping the discharge.

  However, this may be configured such that, for example, when the user once stops the ejection during the same control and then performs a re-operation, the same control is performed again within the predetermined time.

  (2) In addition, the hot water supply amount restriction control in the best embodiments 1 and 2 is automatically performed in any of the cases in response to the end of the boiling through the boiling operation or the boiling operation during the boiling. However, for example, a cavitation prevention mode may be provided, and the control may be performed only when this mode is selected and set.

  (3) Unlike the above case, the hot water supply amount restriction control for reducing the discharge amount may be performed every time (every time it is used).

  However, even in that case, it is not a case corresponding to the end of the boiling after passing through the boiling state as described above, but a water heater and a heat heater corresponding to a decrease in the heat retention temperature during “magic bottle heat retention” by turning off the heat insulation heater. In the case of reheating up to a predetermined heat-retaining temperature that does not cause boiling due to, the control is not performed.

It is the longitudinal cross-sectional view seen from the side which shows the structure of the electric pot main-body part which concerns on the best Embodiment 1 of this invention. It is a top view of the electric pot main-body part. It is an expanded vertical sectional view of the flow sensor part of the electric pot main body part. It is a control circuit diagram of the electric pot main body part. It is a flowchart which shows the hot water supply amount limiting method of the hot water supply start initial stage of the same electric pot. It is a flowchart which shows the hot water supply amount limiting method at the time of the hot water supply start of the electric pot which concerns on best Embodiment 2 of this invention.

Explanation of symbols

  1 is a container body, 2 is a lid, 3 is an inner container, 4A is a hot water heater, 4B is a warming heater, 5 is a hot water supply passage, 6 is an electric hot water supply pump, 7 is an outer case, 10 is an inner cylinder, 11 is an outer cylinder , 12 are temperature sensors, 43a and 43b are heat insulation selection switches, and 60 is a microcomputer control unit.

Claims (4)

  Heating control for heating the inner container, heating means for heating the water in the inner container, and boiling the water in the inner container by operating the heating means to heat the water, and then keeping it at a predetermined temperature In the electric pot comprising means, an electric hot water supply pump for supplying hot water in the inner container to the outside via a hot water supply passage, and an electric hot water supply pump control means for controlling the driving state of the electric hot water supply pump. When the electric hot water supply pump is driven by driving the electric hot water supply pump, the hot water supply pump control means is configured to limit and control the hot water supply amount within a predetermined time to be smaller than normal at the beginning of the electric hot water supply operation. An electric kettle characterized by that.   2. The electric pot according to claim 1, wherein the hot water supply amount restriction control at the beginning of electric hot water supply is performed only for electric hot water supply operation within a predetermined time after the completion of boiling.   The electric kettle according to claim 1 or 2, wherein the hot water supply amount restriction control is performed by intermittently driving an electric hot water supply pump.   3. The electric pot according to claim 1, wherein the hot water supply amount restriction control is performed by driving the electric hot water supply pump at a voltage lower than normal.

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