JP2806302B2 - Electric pot for milk preparation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric pot for preparing milk for obtaining hot water used for preparing infant milk.

[0002]

2. Description of the Related Art For example, a conventional method has been adopted in which a hot water for preparing infants is boiled in an electric pot or the like, placed in a baby bottle, cooled to a predetermined temperature (for example, 40 ° C.), and used. Have been.

However, it is difficult for a user to accurately determine whether or not the temperature of the hot water in the baby bottle has cooled to a predetermined temperature. This is the actual situation. Therefore, there has been a problem that it is sometimes too hot or too warm.

[0004] Therefore, the development of an electric pot for milk preparation, which is both a water heater and a heat insulator, optimal for keeping the hot water for milk preparation warm, has been straddling.

In view of the above demands, a heating device having an electric heater, a server with a lid which is placed on the heating device and is made of a poorly-heated conductor (for example, heat-resistant glass, etc.) which is heated by the electric heater, are provided. There has been developed an electric pot for preparing milk provided with.

[0006]

By the way, in the milking electric pot having the above structure, the server is usually made of heat-resistant glass which is a heat-defective conductor.
In the process of heating and boiling the water stored in the server, sudden boiling (hereinafter referred to as bumping) may occur, and a phenomenon may occur in which hot water is spilled out.

[0007] The bumping phenomenon is caused by unevenness or irregular shape of the bottom of the server, which is inevitable in the manufacturing process, so that an intimate contact between the server and the electric heater as a heating source cannot be obtained, and This is a phenomenon that occurs when the temperature locally rises and large bubbles are generated in that portion.

The elimination of the bumping phenomenon has become an important issue in an electric pot for milk preparation using a server made of a poorly-heated conductor.

The present invention has been made in view of the above points, and has as its object to prevent a bumping phenomenon that occurs during boiling heating in the process of obtaining hot water for milk preparation.

[0010]

According to the basic structure of the present invention, as a means for solving the above-mentioned problems, a heating device having an electric heater, a heater mounted on the heating device and heated by the electric heater are provided. In an electric pot for milk preparation including a server with a lid made of a heat-defective conductor, temperature detection means for detecting the temperature of the server, and water stored in the server based on the temperature detected by the temperature detection means. Heating control means for controlling the heating to be a predetermined temperature; and obtaining a temperature rise characteristic of water from a change in the detected temperature when the temperature detected by the temperature detecting means reaches a first set temperature range before boiling, First heating adjusting means for setting heating conditions so as to stop the heating state at the time when the estimated heating characteristic near boiling estimated from the heating characteristic is obtained; And to be able to avoid the boiling phenomenon.

In the basic configuration of the present invention, the heating condition is set so that the heating state is stopped when the temperature reaches a second set temperature range higher than the first set temperature range before the estimated temperature rise characteristic is obtained. It is preferable to add a second heating adjusting means to be set, since boiling can be terminated earlier. In this case, the second heating adjusting means sets a time for maintaining the normal heating state by the heating control means, and forcibly stops the heating state after the end of the time. This is preferable in that the bumping phenomenon can be reliably avoided.

It is preferable that a chain having a length capable of contacting the inner bottom surface of the server is detachably attached to the server lid in order to more reliably avoid bumping during boiling heating.

It is preferable to roughen the inner bottom surface of the server in that bumping during boiling heating can be more reliably avoided.

[0014]

According to the basic structure of the present invention, the following effects can be obtained by the above means.

That is, when water contained in a server made of a poorly-heated conductor is heated and boiled by the electric heater of the heating device, the heating is controlled based on the temperature detected by the temperature detecting means by the action of the heating control means. When the temperature detected by the temperature detecting means reaches the first set temperature range before boiling during the heating control, the first heating adjusting means is operated, and the temperature rise characteristic of the water is obtained from the change in the detected temperature,
The heating conditions (that is, the heat conduction characteristics accompanying the temperature rise of the server, the temperature rise of the temperature detecting means, etc.) are set so that the heating state is stopped when the estimated temperature rise characteristics near the boiling point estimated from the temperature rise characteristics are obtained. -Heating conditions in a state where the correlation between the resistance characteristics and the water temperature are matched. Therefore, the bumping phenomenon at the time of boiling heating can be avoided.

In the basic configuration of the present invention, the heating condition is set so that the heating state is stopped when the temperature reaches a second set temperature range higher than the first set temperature range before the estimated temperature rise characteristic is obtained. In the case where the second heating adjusting means to be set is provided, local heating occurs depending on the heating state of the server, and the second set temperature range higher than the first set temperature range before the estimated temperature rise characteristic is obtained. However, in this case, the heating state is stopped by operating the second heating adjusting means, and the boiling can be terminated earlier.

Further, the second heating adjusting means sets a time for maintaining the normal heating state by the heating control means,
When the heating state is forcibly stopped after the end of the time, the heating state is set from a point in time when a second set temperature range higher than the first set temperature range is reached before the first heating condition is reached. The heating is stopped after the normal heating for the time, so that the bumping phenomenon at the time of the boiling heating can be surely avoided.

When a chain having a length capable of contacting the inner bottom surface of the server is detachably attached to the cover of the server, the generation of large bubbles that trigger a bumping phenomenon is suppressed, and the boiling heating is prevented. The bumping phenomenon at the time can be more reliably avoided.

Further, when the inner bottom surface of the server is roughened, the release of bubbles from the inner bottom surface of the server is promoted, so that large bubbles are less likely to be generated, and the bumping phenomenon during boiling heating is more reliably avoided. it can.

[0020]

According to the basic structure of the present invention, when heating and boiling water contained in a server made of a poorly-heated conductor, the temperature detected by the temperature detecting means during the heating control by the heating control means before the boiling. When the temperature reaches the first set temperature range, the temperature rise characteristic of water is obtained from the change in the detected temperature by the action of the first heating adjusting means, and the estimated temperature rise characteristic near boiling estimated from the temperature rise characteristic is obtained. Heating conditions such that the heating state is stopped at the time when the temperature is reached (that is, the heating conditions in which the correlation between the heat conduction characteristics accompanying the temperature rise of the server, the temperature rise-resistance characteristics of the temperature detection means, and the water temperature is matched). Is set in advance, without being affected by the fact that the heat conduction characteristics differ depending on the temperature range of the server consisting of the heat-defective conductors, and that the temperature-resistance characteristics of the temperature detection means are unstable. With adaptable to heating conditions,
When a heating state different from normal boiling heating (for example, a heating state in which a bumping phenomenon is likely to occur) is obtained, there is an effect that this can be prevented beforehand.

[0021]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

First Embodiment FIG. 1 shows an electric pot for preparing milk according to a first embodiment of the present invention.

An electric pot for preparing milk according to the present embodiment includes a heating device 1 having an electric heater 3 and a server 2 with a lid placed on the heating device 1 and heated by the electric heater 3. It is configured.

The heating apparatus 1 includes upper and lower cases 4 and 5 each formed of a synthetic resin (for example, polyethylene terephthalate or the like) constituting the upper and lower box portions. The lower portion and the upper peripheral portion are fitted and integrated with each other to form a low waist table. The lower end opening of the lower case 5 is closed by a bottom plate 6 made of sheet metal.

At the upper end opening of the upper case 4, there is formed a vertical peripheral wall 7 bent downward and extended, and at the lower end of the vertical peripheral wall 7, an engaging portion 8 having a U-shaped cross section is formed. Have been. When the server 2 is placed on the heating device 1, the vertical peripheral wall 7 covers the bottom of the server 2 to secure a stable placement state, and also functions to prevent heat dissipation from the radiator plate 11 described below. .

A locking edge 10 integrally formed on the outer periphery of a substantially disc-shaped metal protection frame 9 is locked to the engaging portion 8 from above. The protective frame 9 has a dish-like structure with a predetermined depth, and a heating element is placed on a bottom flat surface in a disc-shaped heat sink 11 made of a good conductor (for example, aluminum or an aluminum alloy). (For example,
An electric heater 3 formed by casting a sheath heater 12) is mounted and fixed. The protection frame 9 also functions as a heat shield plate for preventing the heat of the electric heater 3 from being radiated downward. The radiator plate 11 is mounted by locking a boss portion 11a integrally projecting from a lower surface of the radiator plate 11 into a support hole 9a formed in the protective frame 9 and screwing the protective frame 9 to an appropriate position. The fixed state is to be secured. Then, the server 2 is placed on the radiator panel 11, and the water W in the server 2 is heated by heat conduction from the radiator panel 11. Also,
First and second sensor fitting holes 13 and 14 for fitting and installing a temperature sensor 21 which is a temperature detecting means are formed in the central portions of the radiator 11 and the protection frame 9 as described later. ing.

On the other hand, in the center of the inside of the lower case 5,
A circular support portion 5 having a predetermined diameter and protruding upward in a trapezoidal cross section.
a is formed integrally, and a space 15 formed below the circular support portion 5a has a control circuit storage box 16 containing a control circuit for controlling the energization of the electric heater 3 and the like.
Are mounted on the lower surface of the circular support portion 5a with screws.

The control circuit storage box 16 is made up of upper and lower boxes 32 and 33 made of synthetic resin (for example, made of polypropylene) which are forcibly fitted and connected to each other. The lower box 33
It is built in with screws.

The front side outer wall of the control circuit storage box 16 (specifically, the front side outer wall of the upper box body 32)
An operation panel unit 34 including various switch operation units and various display units is provided.

On the other hand, the lower case 5 in the heating device 1
In the front side of the peripheral wall, an oval opening 40 long in the left-right direction is provided.
The operation panel 34 of the control circuit storage box 16 faces the opening 40 so that the outer surface thereof and the outer peripheral surface of the heating device 1 are flush with each other. With this configuration, the control circuit storage box 16 and the operation panel unit 34 can be unitized, and the control panel unit 34 can be controlled only by facing the opening formed on the outer peripheral surface of the heating device 1. The circuit housing box 16 and the operation panel section 34 can be assembled, and the operation panel section 34 and the microcomputer board 17 can be assembled.
(That is, the control circuit) can be extremely short. As a result, the number of parts and the number of assembling steps can be significantly reduced.

Incidentally, the temperature sensor 21 includes a sensor holder 23 having a thermistor 22 serving as a temperature sensing part therein,
A support cylinder 2 that engages with a flange 23a formed on the outer periphery of the lower end of the sensor holder 23 and supports the sensor holder 23 via the flange 23a so as to be able to move up and down from below.
4, a sensor cap 25 for inserting the support cylinder 24 in a vertically movable state, and a flange-shaped spring receiver 26 formed on the outer periphery of an upper end of the support cylinder 24 and a bottom face of the sensor cap 25. And a spring (for example, a coil spring) 27 which constantly urges the support cylinder 24 upward. At the lower end of the support cylinder 24, a magnet 30 which functions as a set sensor for detecting the presence or absence of the server 2 on the electric heater 3 is provided in combination with a reed switch 31 described later.

In the temperature sensor 21, the sensor holder 23 projects upward by a predetermined amount through the first fitting hole 13 formed in the center of the heat sink 11 of the electric heater 3,
A second sensor cap 25 is formed at the center of the protection frame 9.
The support cylinder 24 penetrates the fitting hole 14 and the circular support portion 5a
Hole 28 formed in the hole and control circuit storage box 1
The sensor cap 25 is mounted and fixed on the circular support portion 5a in a state of being loosely fitted in the notch hole 29 formed in the top plate 6 (that is, the top plate of the upper box body 32). ing.

Further, the microcomputer board 1
7 is a magnet 3 attached to the temperature sensor 21.
A reed switch 31 is provided at a position opposing the sensor 2 and the distance between the reed switch 31 and the magnet 30 is determined when the server 2 is not mounted on the electric heater 3 (that is, the sensor in the temperature sensor 21). Holder 23
Is raised), the magnetic force of the magnet 30 does not act, and when the server 2 is placed on the electric heater 3,
The sensor holder 23 is set down so that the magnetic force of the magnet 30 can act. Accordingly, the reed switch 31 is turned ON / OFF in accordance with the placement / non-placement of the server 2 on the electric heater 3, and the electric heater 3 (specifically,
The energization of the heating element 12) is controlled.

That is, in the case of the present embodiment, the temperature sensor 21 performs the hot water temperature detecting operation for detecting the hot water temperature in the server 2 and the empty detecting operation of the server 2.
At the time of empty detection, the power supply to the electric heater 3 is cut off, thereby ensuring safety and preventing unnecessary power consumption.

On the other hand, the server 2 is made of a transparent heat-resistant glass, and has a large-diameter central portion in the vertical direction and a small-diameter wide-mouthed bottle at both upper and lower ends. It is formed on a loose concave round surface corresponding to the loose convex round surface. Further, a cylindrical water supply port 53 having a beak-shaped pouring port 52 on the front side is formed at the upper end of the server 2, and the base of the water supply port 53 is a slightly smaller neck 54. . The neck 54 serves as a mounting portion for the handle 55 as described later. Further, the water supply port 53
The pouring port 52 is covered with a removable lid 56 made of a transparent heat-resistant synthetic resin. The lid 56 is composed of a lid main body 56a that closes the water supply port 53 and has a steam vent hole 57, and a pouring port lid 56b that closes the pouring port 52. Reference numeral 58 denotes an annular engagement piece that is engaged with the inner periphery of the water supply port 53 to prevent the lid 56 from falling off.

The handle 55 is made of a synthetic resin comprising a C-shaped grip portion 55a gripped by a user and a support portion 55b which connects the upper and lower inner ends of the grip portion 55a and is in close contact with the outer peripheral surface of the server 2. And is attached via a handle ring 59 wound around the neck 54 of the server 2. Reference numeral 60 denotes a tightening bolt for connecting the handle ring 59 to the handle 55.

In this embodiment, a chain 61 having a length capable of contacting the inner bottom surface 2a of the server 2 is detachably attached to the lid 56. The chain 61 is attached by detachably engaging an eggplant 63 attached to the upper end of the chain 61 to an attachment hole 62 formed at the edge of the vapor vent hole 57 in the lid 56. The chain 61 suppresses the generation of large bubbles by utilizing the fact that the portion in contact with the server inner bottom surface 2a swings during boiling heating. Accordingly, the bumping phenomenon caused by the local heating during the boiling heating can be avoided.

The chain 61 used is as follows.
A material made of a metal having excellent thermal conductivity and corrosion resistance is optimal, and a material having many end faces that easily hold air bubbles (see FIG. 2) or a material called a ball chain (see FIG. 3) is desirable. In addition, even if an annular spring 64 shown in FIG. 4 is arranged at the bottom of the server 2 instead of the chain 61, a bumping prevention effect can be expected.

As shown in FIG. 5, the server 2
When the inner bottom surface 2a is roughened by shot blasting or chemical treatment, only small bubbles are generated at the time of boiling heating, which is effective in preventing bumping.

Next, the structure of the electric components in the electric pot for milk preparation of this embodiment will be described with reference to FIG.

The microcomputer board 17 includes:
As shown in FIG. 6, a control circuit 36 using a microcomputer 35 is built in, and the operation of the heater drive circuit 37 is controlled by the control circuit 36.

The microcomputer 35 is provided with a heating control means 38 for controlling the heating of the water W stored in the server 2 to a predetermined temperature based on the temperature detected by the temperature sensor 21, and the detection by the temperature sensor 21. A temperature rise characteristic of water is obtained from a change in the detected temperature when the temperature reaches a _first set temperature T ₁ (for example, 130 ° C.) before boiling, and estimation near boiling is estimated from the temperature rise characteristic. First heating adjusting means 39 for setting a heating condition so as to stop the heating state when the temperature rising characteristic is obtained, and a second heating temperature higher than the first set temperature T ₁ before reaching the first heating condition. The second heating adjusting means 40 for setting the heating condition so that the heating state is reached when the temperature reaches the set temperature T ₂ (for example, 162 ° C.)
And

The heating condition set by the first heating adjusting means 39 is a time t ₁ (for example, for maintaining the normal heating state by the heating control means 38 after the estimated temperature rise characteristic is obtained). 176 seconds).

On the other hand, the heating condition set by the second heating adjusting means 40 is a time t ₂ for maintaining the normal heating state by the heating control means 38 after the temperature reaches the _second set temperature T _2. (For example, 10 minutes).

The microcomputer 35 is supplied with a DC current obtained by a transformer 42 and a rectifier 43 from an AC power supply 41 of the heater drive circuit 37, and supplies a frequency synchronizing signal by power supply from the AC power supply 41. The frequency synchronization signal generated by the input circuit 44 is to be input. Further, the input side of the microcomputer 35 notifies the temperature sensor 21, various operation keys 45 provided on the operation panel unit 34, various display elements 46, and various states in various operation modes by sound. An alarm 47 and the like are connected, and a triac drive circuit 48 is connected to the output side. The triac 49 controls the energization of the heater drive circuit 37 to the electric heater 3 through a triac 49, and the heating state is changed as needed. I am getting it.

Next, with reference to a flowchart shown in FIG. 7 and a time chart shown in FIG. 8, the boiling control in the electric pot for milk preparation of this embodiment will be described.

[0047] When the power is turned on, the detected temperature T and the start of boiling lower limit temperature Tmin (e.g., 55 ° C.) by the temperature sensor 21 in step S ₁ is made compared with, T <T
If it is determined min, and boiling heating the electric heater 3 is ON is started in step S _2.

In the course of the boiling heating, the temperature sensor 2
1 is the first set temperature T ₁ (for example, 13
0 ° C.) (at this time, the water temperature is the temperature before boiling) (step S ₃ ), step S ₄
Then, the temperature rise at that time (in other words, the slope of the temperature rise curve A) ΔT (see FIG. 8) is obtained. Since the temperature rise of ΔT varies with the amount of water in the server 2, processing executed in step S ₄ is also a water determination process. Estimated temperature rise of ΔT in the vicinity of the boiling temperature thus in step S ₅ based on the degree of temperature increase ΔT obtained
a (see FIG. 8) is set. The estimated temperature rise ΔTa
Is several prepared for water by determined in step S _4, the estimated temperature increase of ΔTa corresponding to the amount of water is set.

[0049] Thereafter, if the slope of the temperature rise curve A reaches the estimated temperature increase of ΔTa whether the determination in step S ₆ is made in boiling ends the routine proceeds to step S ₇ when a positive result is obtained in this And at the same time step S ₈
Then, the heating addition timer (in other words, the first heating adjusting means 39) for the time period t ₁ (176 seconds in this embodiment) is operated. Then, the heating summing timer in step S ₉ is transferred to the heat keeping control to be confirmed to have counted up.

In other words, when heating and boiling the water W stored in the server 2 made of a poorly-heated conductor, the temperature T detected by the temperature sensor 21 during the heating control by the heating control means 38 is the first set temperature T before the boiling. ₁ (for example, 1
When the temperature reaches 30 ° C.), the temperature rise characteristic of the water (in other words, the temperature rise ΔT) is obtained from the change in the detected temperature T by the action of the first heating adjusting means 39. The first heating condition (that is, the first heating condition (that is, the estimated temperature increase ΔTa) near the estimated boiling point (in other words, the estimated temperature increase ΔTa)
The heating addition timer) is set, and the heat conduction characteristics are different depending on the temperature range of the server 2 composed of the heat-defective conductor, and the temperature-resistance characteristics of the temperature sensor 21 are not affected by the instability. It can be adapted to a preset heating state.

Meanwhile, if a negative determination is made in step S _6, the detection by the temperature sensor 21 the temperature T and the second set temperature T ₂ in step S ₁₀ (for example, 162 ° C.) compared with is made, the second set temperature T when it reaches the ₂ is confirmed, timed t ₂ (in the present embodiment, 10 min) in step S ₁₁ (in other words, the second heating adjusting means 40) heated forced timer to operate the. Then, step S ₁₂
When it is confirmed that the forcible heating timer has counted up, the process proceeds to the heat retention control. If you do this,
When a local rise in server temperature that causes bumping occurs, the temperature T detected by the temperature sensor 21 rises quickly to a high temperature (that is, refer to the temperature rise curve B in FIG. 8), so that boiling due to normal heating is obtained. by operating the heating forced timer when it reaches the second set temperature T ₂ before being, the occurrence of bumping is able prevented by terminating the boiling heat as soon as possible.

That is, the estimated temperature rise characteristic (in other words,
Before the estimated temperature increase ΔTa) is obtained, the temperature sensor 21
When the detected temperature T reaches a second set temperature T ₂ (for example, 162 ° C.) higher than the first set temperature T ₁ , the second
The second heating condition (that is, the second heating condition)
Since the boiling is terminated early by setting the addition timer, if the heating state is different from the normal boiling heating (for example, the heating state where bumping phenomenon is likely to occur), this will be done beforehand. Can be prevented.

Second Embodiment FIG. 9 shows an electric pot for preparing milk according to a second embodiment of the present invention.

In the case of the present embodiment, a large number of small holes 65,
65. A bottomed cylindrical body 66 made of a corrosion-resistant metal having 65. It is desirable that the bottomed cylindrical body 66 is vertically extended to the vicinity of the inner bottom surface 2a of the server 2. With this configuration, the bubbles generated from the server inner bottom surface 2a during the boiling heating do not grow significantly due to the presence of the pores 65, 65,..., And the bumping phenomenon is avoided. The other configuration and operation and effect are the same as those of the first embodiment, and the description is omitted to avoid duplication.

The present invention is not limited to the configuration of each of the above-described embodiments, and it is needless to say that the design can be changed as appropriate without departing from the gist of the invention.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view of an electric pot for preparing milk according to Example 1 of the present invention.

FIG. 2 is a partially enlarged view of a chain of the electric pot for milk preparation according to the first embodiment of the present invention.

FIG. 3 is a partially enlarged view of another chain which can be used in the electric milk pot according to the first embodiment of the present invention.

FIG. 4 is a plan view of a spring that can be used instead of the chain in the electric pot for preparing milk according to the first embodiment of the present invention.

FIG. 5 is an enlarged cross-sectional view of the inner bottom surface of the server in the electric pot for milk preparation according to the first embodiment of the present invention.

FIG. 6 is a connection diagram of electric elements in the electric pot for milk preparation according to Example 1 of the present invention.

FIG. 7 is a flowchart showing boiling heating control in the milk-supplying electric pot according to the first embodiment of the present invention.

FIG. 8 is a time chart illustrating boiling heating control in the electric milk pot according to the first embodiment of the present invention.

FIG. 9 is a vertical cross-sectional view of the electric pot for preparing milk according to the second embodiment of the present invention.

[Explanation of symbols]

1 is a heating device, 2 is a server, 2a is an inner bottom surface, 3 is an electric heater, 17 is a microcomputer board, 21 is a temperature detecting means (temperature sensor), 35 is a microcomputer, 36 is a control circuit, and 38 is heating control means. , 39 is the first
The heating adjusting means, 40 is a second heating adjusting means, and 61 is a chain.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-191925 (JP, A) JP-A-62-120815 (JP, A) JP-A-60-160925 (JP, A) 93365 (JP, U) JP-B 36-12490 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) A47J 27/21 101

Claims (5)

(57) [Claims] 1. An electric pot for milk preparation, comprising: a heating device having an electric heater; and a server with a lid placed on the heating device and made of a poorly-heated conductor heated by the electric heater, Temperature detecting means for detecting the temperature of the server, heating control means for controlling the heating of water stored in the server to a predetermined temperature based on the temperature detected by the temperature detecting means, and A temperature rise characteristic of water is obtained from a change in the detected temperature when the detected temperature reaches a first set temperature range before boiling, and an estimated temperature rise characteristic in the vicinity of boiling estimated from the temperature rise characteristic is obtained. When
And a first heating adjusting means for setting a heating condition so as to stop the heating state . 2. The method according to claim 1 , further comprising the step of:
When a second set temperature range higher than the first set temperature range is reached
Set the heating condition so that the heating state is stopped by the second step.
2. The electric pot for milk preparation according to claim 1, further comprising heat adjusting means . 3. The method according to claim 2, wherein the second heating adjusting means sets a time for maintaining the normal heating state by the heating control means, and forcibly stops the heating state after the end of the time. 3. The electric pot for milk preparation according to claim 2, wherein The wherein the lid of the server, to the claims 1, characterized in that mounted detachably chain having a length that may contact with the inner bottom surface of the server of any one of claims 3 Electric pot for milk preparation. 5. The electric pot for milk preparation according to claim 1, wherein an inner bottom surface of the server is roughened.