JP6050176B2 - Liquid heater - Google Patents

Description

  The present invention includes a bottomed cylindrical storage container for storing a liquid to be heated, a plate-shaped electric heater for heating the liquid in the storage container, and the electric heater sandwiched and fixed between the outer surface of the bottom of the storage container The heater holding member, the temperature detecting means for detecting the temperature of the liquid in the storage container, and when the temperature detected by the temperature detecting means is equal to or higher than the set temperature for stopping heating to prevent emptying, the electric heater is energized. Control means for shutting off, and energization shutting means for shutting off energization to the electric heater when heated above the set temperature for overheating prevention set higher than the set temperature for stopping heating by heat transfer from the storage container The present invention relates to a liquid heater.

Such a liquid heater heats a liquid (for example, water) in a storage container with an electric heater, and specific examples include a humidifier, an electric kettle, and an electric pot.
Such a liquid heater is configured to stop the heating operation of the electric heater by the control means when the detected temperature of the temperature detecting means becomes equal to or higher than the heating stop set temperature for preventing emptying. Thus, a heating stop function for automatically stopping heating is provided. Here, the set temperature for stopping heating is set to a temperature higher than the boiling temperature of the liquid in the storage container, for example. That is, by operating this heating stop function, the so-called emptying, in which the heating operation of the electric heater is continued even though there is no liquid in the storage container, is prevented.

  Furthermore, when the temperature detection means (for example, thermistor) or the control means fails and the heating stop function is not activated, the air heating is not stopped and the liquid heater is prevented from being damaged by overheating. In order to achieve this, there is provided an energization interrupting means for interrupting energization to the electric heater when heated by the heat transfer from the storage container to a temperature higher than the set temperature for overheating prevention that is higher than the set temperature for stopping heating.

In the past, the following structure has been proposed as an arrangement structure of such energization interruption means.
That is, the electric heater is applied to the central portion of the outer surface of the circular bottom of the storage container, and the temperature fuse, which is an example of the energization interruption means, is applied to the electric heater on the outer surface of the bottom of the storage container. It is provided in such a form that it is in contact with a portion on the outer peripheral side with respect to the portion being present (see, for example, Patent Document 1).
Incidentally, in Patent Document 1, a heat shield plate that covers the heater pressing member from the lower side is provided on the lower side of the heater pressing member at a distance from the heater pressing member. In form, it is attached to this heat shield. That is, the energization interrupting means is provided in a state in which heat is easily transferred from the bottom of the storage container but is not easily transferred directly from the electric heater.

JP 2010-88557 A

By the way, to prevent damage to the liquid heater due to overheating when the heating stop function becomes inoperable due to a failure of the temperature detection means or control means, the overheat prevention set temperature is set to the heating stop set temperature. Although it is higher, it is preferable to set the difference from the set temperature for stopping the heating as small as possible so as to cut off the energization to the electric heater as soon as possible.
On the other hand, when the set temperature for overheating prevention is set in this way, depending on the installation location of the temperature detecting means and the energization interruption means, the energization interruption means may incorrectly energize the electric heater when the heating stop function can be operated normally. It is necessary to prevent this from happening.
For example, even if the temperature detected by the temperature detection means is equal to or higher than the set temperature for stopping heating and the electric heater is cut off by the control means, the electric cut-off means is overheated due to overshoot by the electric heater. In some cases, the energization interrupting means is operated so as to interrupt the energization to the electric heater when heated to the set temperature for prevention.
Alternatively, even if the temperature detected by the temperature detection means is lower than the set temperature for stopping heating and the control means does not operate to cut off the power supply to the electric heater, the power supply cut-off means exceeds the set temperature for overheating prevention. There is a case where the heating is interrupted and the energization to the electric heater is interrupted by the energization interruption means.
That is, when the heating stop function is activated, when the energization to the electric heater is interrupted, the liquid heater can be reused as usual. When energization is interrupted, it may be troublesome to reuse the liquid heater, for example, it may be necessary to replace the energization interrupting means.

In the conventional liquid heater, the energization interrupting means is provided in a state where heat is easily transferred from the bottom of the storage container, but is difficult to transfer heat directly from the electric heater. Heating by heat transfer from the bottom is dominant.
Therefore, when the heating stop function can be operated normally, the temperature of the bottom of the storage container is the highest at the boiling temperature of the liquid in the storage container or a temperature close thereto. It will be reliably maintained at a temperature lower than the temperature. Therefore, it is possible to sufficiently prevent a malfunction such that the energization of the electric heater is erroneously interrupted by the energization interrupting means when the heating stop function is normal.

  However, the heating of the energization interruption means is dominated by the heat transfer from the bottom of the storage container, and it is difficult to transfer the heat directly from the electric heater. Since it takes a relatively long time for the energization shut-off means to be heated to the set temperature for overheating prevention after the temperature at the location where the temperature is detected by the temperature detecting means exceeds the preset temperature for stopping heating, the electric heater There is a possibility that the interruption of the energization of the heater will be delayed, and there is room for improvement in accelerating the interruption of the energization to the electric heater and surely preventing damage to the liquid heater due to overheating.

  The present invention has been made in view of such circumstances, and its purpose is to prevent malfunctions in which energization to the electric heater is erroneously interrupted by the energization interrupting means when the heating stop function is operating normally. An object of the present invention is to provide a liquid heater capable of speeding up the interruption of energization to the electric heater by the energization interruption means at the time of abnormality when the heating stop function becomes inoperable.

In order to achieve the above object, a liquid heater according to the present invention includes a bottomed cylindrical storage container that stores a liquid to be heated, a plate-shaped electric heater that heats the liquid in the storage container, and the electric heat A heater pressing member that clamps and fixes the heater between the outer surface of the bottom portion of the storage container, a temperature detection means that detects the temperature of the liquid in the storage container, and a temperature detected by the temperature detection means prevents the emptying. When the temperature is higher than the set temperature for stopping heating, the control means for cutting off the energization to the electric heater, and the set temperature for preventing overheating set higher than the set temperature for stopping heat by heat transfer from the storage container A liquid heater comprising an energization interruption means for interrupting energization to the electric heater when heated to
The heater holding member includes a contact portion that contacts the outer surface of the bottom of the storage container in a state where the electric heater is sandwiched and fixed between the electric heater and the outer surface of the bottom of the storage container.
The energization cut-off means is disposed in a state of being applied to the contact portion of the heater pressing member.

According to the above characteristic configuration, heat transfer from the electric heater to the energization cutoff means is performed by a heat transfer path passing through the bottom of the storage container and the contact portion of the heater pressing member, and a heat transfer path passing only through the heater pressing member. It will be performed by two routes.
When the liquid is present in the storage container, the heat transferred from the electric heater to the storage container is absorbed by the liquid in the storage container, so that the bottom of the storage container and the contact portion of the heater pressing member Heat transfer from the electric heater to the energization cutoff means in the heat transfer path passing through is suppressed, and the temperature rise of the energization cutoff means is suppressed. Therefore, even if the set temperature for overheating prevention is set so that the difference from the set temperature for stopping heating is as small as possible, the temperature of the power-off means is used for overheating prevention when liquid is present in the storage container. It is possible to reliably maintain a temperature lower than the set temperature, and sufficiently prevent malfunctions such as energization to the electric heater accidentally interrupted by the energization interrupting means when the heating stop function can be operated normally. Can do.
On the other hand, when there is almost no liquid in the storage container as a heat absorption source of heat of the electric heater at the time when the heating stop function cannot be operated, the energization cutoff means passes through the storage container and the contact portion of the heater pressing member. Since it is heated by the heat of the electric heater that is transferred by the heat transfer path and the heat of the electric heater that is transferred by the heat transfer path that passes only through the heater holding member, the energization cutoff means is the temperature by the temperature detection means in the storage container. After the temperature of the detection location exceeds the set temperature for stopping heating, the temperature is quickly heated to the set temperature for preventing overheating, and the interruption of energization to the electric heater can be speeded up.
Therefore, when the heating stop function cannot be operated normally, while the heating stop function can be operated normally, the energization interrupting means prevents the malfunction of the power heater being cut off accidentally. It is possible to provide a liquid heater that can quickly cut off the energization of the electric heater.

According to a further feature of the liquid heater according to the present invention, the heater pressing member is attached to the storage container by fixing the contact portion to the outer surface of the bottom of the storage container.
The energization shut-off means is in contact with a portion fixed to the outer surface of the bottom portion of the storage container in the contact portion or in the vicinity thereof.

According to the above characteristic configuration, the heat transfer between the contact portion of the heater pressing member and the bottom portion of the storage container is further improved at the location where they are fixed and in the vicinity thereof. And since the electricity interruption | blocking means is applied to the part currently fixed to the outer surface of the bottom part of a storage container in the contact part of a heater pressing member, or its vicinity, contact | abutting of the bottom part of a storage container and a heater pressing member Heat transfer from the electric heater to the energization shut-off means in the heat transfer path passing through the section becomes even better, so that when the heating stop function cannot be operated, the energization shut-off means is heated to the set temperature for preventing overheating. It will be even faster.
Therefore, when the heating stop function becomes inoperable, it is possible to further speed up the interruption of energization to the electric heater by the energization interruption means.

  A further characteristic configuration of the liquid heater according to the present invention is that the contact portion is fixed to the outer surface of the bottom portion of the storage container by seam welding.

According to the above characteristic configuration, the contact portion of the heater pressing member to the outer surface of the storage container is fixed by seam welding that can increase the fixed area (contact area) thereof. Heat transfer from the electric heater to the energization cutoff means in the heat transfer path passing through the contact portion of the pressing member is further improved. As a result, when the heating stop function stops operating, the heating to the set temperature for preventing overheating of the energization cutoff means is further accelerated.
Accordingly, when the heating stop function becomes inoperable, it is possible to further speed up the interruption of energization to the electric heater by the energization interruption means.

A further characteristic configuration of the liquid heater according to the present invention is that the electric heater is configured with an opening in a central portion,
The electric heater is provided in a state where the opening is positioned at the center of the outer surface of the bottom portion of the storage container and applied to the outer surface of the bottom portion,
The temperature detection means is provided so as to detect the temperature of the central portion of the outer surface of the bottom of the storage container as the temperature of the liquid in the storage container;
The heater pressing member is configured to cause at least the abutting portion to abut on portions facing each other across the central portion of the outer surface of the bottom portion in a region on the outer peripheral side of the outer surface of the bottom portion;
The at least two energizing / blocking means are provided in a state of being respectively applied to the abutting portions located at portions facing each other across the central portion of the outer surface of the bottom portion.

According to the above-described characteristic configuration, when the heating stop function becomes inoperable when the storage container is tilted, the bottom portion of the storage container above the power supply cutoff means is provided for at least one power supply cutoff means. Therefore, the electric heater can be quickly cut off from being energized.
Therefore, damage to the liquid heater due to overheating can be reliably prevented.

A further characteristic configuration of the liquid heater according to the present invention is provided in a state where the electric heater is applied to the outer surface of the bottom of the storage container,
The temperature detection means is provided to detect the temperature of the outer surface of the bottom of the storage container as the temperature of the liquid in the storage container;
In a portion different from the temperature detection location by the temperature detection means at the bottom of the storage container, a recess is provided in a form in which the inner surface of the bottom is recessed downward,
The heater pressing member is configured to include the contact portion corresponding to a portion corresponding to the concave portion on the outer surface of the bottom portion,
The energization cutoff means is applied to the abutting portion that abuts on a portion corresponding to the concave portion on the outer surface of the bottom portion.

According to the above characteristic configuration, when the storage container is tilted, even if the amount of the liquid in the storage container becomes small, the liquid is present at the temperature detection portion by the temperature detection means at the bottom of the storage container. Therefore, it is possible to avoid as much as possible that no liquid is present in the bottom portion of the storage container above the energization interrupting means. Therefore, even if the set temperature for preventing overheating is set so that the difference from the set temperature for stopping heating is further reduced, the energization cutoff means is set even though the detected temperature of the temperature detecting means is lower than the set temperature for stopping heating. Can be reliably avoided from being heated to the set temperature for preventing overheating.
Therefore, when the storage stop function is normal when the heating stop function can be operated, even if the amount of liquid in the storage container is small, the power supply to the electric heater is erroneously cut off by the power cut-off means. Can be more reliably prevented.

A further characteristic configuration of the liquid heater according to the present invention is provided with a heat shield plate that covers the heater pressing member from a side opposite to the electric heater side of the heater pressing member,
The energization cutoff means is attached to the heat shield plate via an attachment member in a state of being applied to the contact portion.

Here, since the heat shield is provided for the purpose of effectively shielding the heat of the electric heater, the heat shield is provided in a state spaced from the heater pressing member. Can be easily attached by a joining method using screws that are easy to work.
On the other hand, since the heater holding member is provided for the purpose of sandwiching and fixing the electric heater with the outer surface of the storage container, the heater holding member is provided in contact with the electric heater. It is difficult to attach a member.
Therefore, as in the above characteristic configuration, when the current-carrying means is attached to the heat shield plate via the mounting member in a state of being applied to the contact portion, the work for attaching the current-carrying means is facilitated, Cost can be reduced.
Therefore, it is possible to reduce the cost of the liquid heater.

  A further characteristic configuration of the liquid heater according to the present invention is that an energization shut-off actuating portion that acts to cut off the energization to the electric heater automatically when the energization cut-off means is heated to the overheat prevention set temperature or higher. It is in the point comprised with.

In other words, the energization cut-off acting part is configured to include, for example, a thermal fuse or a one-shot type thermostat so that the energization to the electric heater is automatically cut off when heated to a set temperature for preventing overheating. Works.
Therefore, as in this feature configuration, when the energization interrupting means is configured, it is not necessary to use a control means (for example, a microcomputer) that causes an increase in cost by including an energization interrupting action unit, or Further, it is not necessary to secure a program area for the energization interruption means, so that the cost can be reduced.
Therefore, it is possible to reduce the cost of the liquid heater.

Perspective view showing the appearance of the humidifier Disassembled perspective view of humidifier Humidifier vertical front view Longitudinal front view near the bottom of the storage container in the humidifier An exploded perspective view of the vicinity of the bottom of the storage container in the humidifier Cross-sectional bottom view showing the vicinity of the bottom of the storage container in the humidifier

Hereinafter, based on the drawings, an embodiment when the present invention is applied to a humidifier (an example of a liquid heater) H will be described.
As shown in FIGS. 1 to 3, the humidifier H includes a substantially square-bottomed tubular outer case 100 and a lid 200 that can freely open and close the upper opening 2 of the outer case 100. In addition, a bottomed cylindrical storage container 1 that stores water (an example of a liquid) W to be heated is provided inside the exterior case 100. The lid body 200 is swingably supported by a hinge portion 3 provided at the opening edge of the opening portion 2 of the exterior case 100, and the exterior case 100 is operated by a swinging operation with the hinge portion 3 as a swing axis. The opening 2 is configured to be openable and closable.

As shown in FIG. 3, the outer case 100 is fitted with a substantially rectangular frame-shaped rim member 5 in the rim portion of a generally bottomed rectangular tube-shaped case body 4, and the storage container 1 is fitted into the rim member 5. The opening 2 of the exterior case 100 is formed by the rim member 5.
As shown in FIGS. 3 and 4, in the outer case 100, the plate-like electric heater 6 that heats the water W in the storage container 1, and the electric heater 6 are placed between the outer surface of the bottom 1 </ b> B of the storage container 1. A heater pressing plate (an example of a heater pressing member) 7 to be clamped and fixed, a temperature sensor 8 for detecting the temperature of the water W in the storage container 1 (an example of a temperature detecting means, such as a thermistor), and a temperature detected by the temperature sensor 8 When the temperature becomes equal to or higher than the set temperature for stopping heating to prevent empty heating, the controller 9 (an example of control means) that cuts off the power supply to the electric heater 6 and the setting for stopping heating by heat transfer from the storage container 1 An energization interrupting means 40 for interrupting energization of the electric heater 6 when it is heated to a set temperature for preventing overheating set higher than the temperature is incorporated.
As shown in FIGS. 1 and 2, an operation unit 10 that transmits operation control information to the control unit 9 is provided on the side surface of the outer case 100, and a handle 11 is provided on the upper part of the outer case 100. It has been.

  As shown in FIGS. 3 and 4, in the present invention, the heater pressing plate 7 holds the electric heater 6 between the outer surface of the bottom 1B of the storage container 1 and fixes the bottom 1B of the storage container 1. An outer peripheral contact portion 7d (an example of a contact portion) that contacts the outer surface of the heater pressing plate 7 is provided in a state of being applied to the outer peripheral contact portion 7d of the heater pressing plate 7. .

Next, each part of the humidifier H will be described.
As shown in FIGS. 3 to 5, the storage container 1 is configured by closing one end opening of a cylindrical peripheral wall 1 </ b> A with a substantially disk-shaped bottom 1 </ b> B, and the bottom 1 </ b> B of the storage container 1 is 3 It is configured to rise upward in a step shape. The outer first stage of the three-stage raised parts is a heater-mounted raised part 1a, and the intermediate second stage is raised upward from the approximate center of the first-stage heater-mounted raised part 1a. The middle third bulge portion 1b bulges upward from the approximate center of the second middle bulge portion 1b to form a sensor mounting bulge portion 1c.
An annular recess 1d that is annularly recessed downward is formed on the outer peripheral portion of the inner surface of the bottom 1B of the storage container 1 by the heater mounting bulge 1a of the peripheral wall 1A and the bottom 1B.

The electric heater 6 is configured in an annular shape having a sensor disposition hole 6 h (an example of an opening) in the center in plan view, and the opening diameter of the sensor disposition hole 6 h in the annular electric heater 6 is the same as that of the storage container 1. The outer diameter of the electric heater 6 is substantially the same as the inner diameter of the heater mounting raised portion 1a at the bottom 1B, and is configured to be smaller than the outer diameter of the heater mounting raised portion 1a at the bottom 1B of the storage container 1. ing.
The annular electric heater 6 is disposed in contact with a portion corresponding to the raised portion 1a for attaching the heater on the outer surface of the bottom 1B of the storage container 1.
Since the electric heater 6 is well known, detailed description and illustration are omitted. For example, a mica heater is housed in a flat annular heater case and configured in a plate shape. The mica heater is configured by winding a heating wire (for example, nichrome wire) around a heat sink made of mica (mica), and the heater case is made of metal having excellent heat conductivity such as aluminum.

In addition, the heater pressing plate 7 is formed in an annular shape that rises upward in a two-stage shape and includes a sensor disposing hole 7h in the center in plan view. The outer first stage of the two stages is a heater that presses the electric heater 6 disposed in contact with the portion corresponding to the raised portion 1a for attaching the heater on the outer surface of the bottom 1B of the storage container 1. It is set as the holding | suppressing part 7a, and the inner 2nd step | stage is made into the inner peripheral side contact part 7b made to contact | abut the part corresponding to the intermediate | middle rise part 1b in the outer surface of the bottom part 1B of the storage container 1. FIG.
In addition, the outer peripheral side of the heater pressing portion 7 a in the heater pressing plate 7, that is, the outer peripheral side that is in contact with the annular portion corresponding to the annular recess 1 d on the outer surface of the bottom 1 B of the storage container 1. A contact portion 7d is provided.

  Then, with the electric heater 6 placed against the portion of the outer surface of the bottom 1B of the storage container 1 corresponding to the raised portion 1a for attaching the heater, the outer peripheral side contact portion 7d of the heater pressing plate 7 is placed on the storage container 1. An annular recess 1d in the bottom 1B of the storage container 1 is disposed so as to contact the annular recess 1d on the outer surface of the bottom 1B and the inner peripheral contact 7b in contact with the intermediate raised portion 1b. The electric heater 6 is clamped and fixed between the outer surface of the bottom 1B of the storage container 1 and the heater pressing plate 7 by joining the outer peripheral side contact portion 7d of the heater pressing plate 7 with seam welding.

4 and 5, reference numeral 15 indicates a seam weld portion where the bottom portion 1 </ b> B of the storage container 1 and the outer peripheral contact portion 7 d of the heater pressing plate 7 are joined by seam welding.
As shown in FIG. 5, the joint between the bottom portion 1B of the storage container 1 and the outer peripheral side contact portion 7d of the heater pressing plate 7 by seam welding is equally spaced in the circumferential direction at the bottom portion 1B of the storage container 1 (ie, the central angle). The seam welded portion 15 at each location has an elongated shape along the circumferential direction of the bottom portion 1B of the storage container 1.

That is, in this embodiment, the electric heater 6 is configured to include a sensor disposition hole 6h at the center, and the electric heater 6 has the sensor disposition hole 6h at the center of the outer surface of the bottom 1B of the storage container 1. The heater pressing plate 7 is provided in a state where it is positioned and applied to the outer surface of the bottom portion 1B, and the outer surface abutment portion 7d of the outer peripheral side of the outer surface of the bottom portion 1B of the storage container 1 is disposed on the outer surface of the bottom portion 1B. It is comprised so that it may contact | abut at least the part which mutually opposes on both sides of the center part.
And although mentioned later for details, the two electricity supply interruption | blocking means 40 are on the outer peripheral side contact part 7d of the heater pressing board 7 located in the part which mutually opposes on both sides of the center part of the outer surface of the bottom part 1B of the storage container 1. It is provided with each applied.

As shown in FIGS. 4 to 6, a heat shield plate 12 that covers the heater pressing plate 7 is further provided from the opposite side (that is, the lower side) of the heater pressing plate 7 to the electric heater 6 side.
The heat shield plate 12 includes a sensor arrangement hole 12 h for arranging the temperature sensor 8. The heat shield plate 12 is configured to cover the lower portion of the electric heater 6 over a wide range, but the outer periphery of the heater pressing plate 7 is provided on a part of the outer peripheral side in order to dispose the current interrupting means 40. A lower opening 13 that exposes the side contact portion 7d (in particular, the seam welded portion 15) to the lower side is formed (see FIGS. 4 and 6).
Two lower open portions 13 are provided corresponding to the positions where the two energization interrupting means 40 are disposed, and each of the lower open portions 13 is provided on the outer peripheral side contact portion 7d (especially the seam welded portion 15) of the heater pressing plate 7. It is formed in a state where it is located on the opposite side with respect to the central portion of the bottom 1B of the storage container 1 in a form to be exposed.
Although illustration is omitted, the heat shield plate 12 is supported above the bottom of the outer case 100 by a plurality of columnar bodies while being connected to the heater pressing plate 7.

As shown in FIGS. 4 to 6, the energization interrupting means 40 includes an energization interrupting action part 41 that acts to interrupt the energization to the electric heater 6 when it is heated to a set temperature for preventing overheating, and its energization. An action part attachment member 42 (an example of an attachment member) for attaching the blocking action part 41 to the outside of the storage container 1 is configured.
In this embodiment, the energization cutoff action part 41 is provided with a thermal fuse (not shown) configured to blow when heated to a temperature higher than the set temperature for preventing overheating. That is, although not shown in the figure, the energization / blocking action portion 41 is configured by filling a heat-conductive resin (not shown) with a thermal fuse in a flexible tube-shaped fuse cover 41c. ing. The energization / blocking action part 41 is provided in a state in which a temperature fuse is connected in the middle of a lead wire (not shown) for supplying driving electric power to the electric heater 6, and the temperature fuse is set at a set temperature for preventing overheating. When heated and blown as described above, energization to the electric heater 6 is cut off.

  As described above, in this embodiment, since the two energization interruption means 40 are provided, the two energization interruption action portions 41 corresponding to the two energization interruption means 40 supply driving electric power to the electric heater 6. They are connected in series in the middle of a lead wire (not shown) to be supplied.

Next, a description will be given of the mounting structure of the energization cutoff operation part 41.
As shown in FIGS. 4 and 5, the action portion mounting member 42 has an end-side standing piece 42b and a front-side standing piece 42c on one end side in the longitudinal direction of the elongated plate-like main body portion 42a. It is formed in a shape that is provided in a state of being spaced apart in the longitudinal direction of the main body portion 42a so that the cylindrical energization blocking action portion 41 can be inserted. The action part mounting member 42 is manufactured by molding a metal plate.
Two end-side standing pieces 42b are provided at an interval in the width direction (short direction) of the main body portion 42a. The height of the end-side standing pieces 42b from the main body portion 42a to the upper side is the front side. It is comprised so that it may become higher than the standing height of the side standing piece 42c.

  The energization cutoff action part 41 is inserted between the two end side standing pieces 42b and the front side standing piece 42c in a posture in which the axial center direction is along the width direction of the main body part 42a of the action part mounting member 42. Then, by bending the two end side upright pieces 42 b along the outer periphery of the energization cutoff action part 41, the energization cutoff action part 41 is supported on the end of the action part mounting member 42. Incidentally, when the end-side standing piece 42b is bent along the outer periphery of the energizing / blocking action portion 41 (specifically, the fuse cover 41c), the surface of the end-side standing piece 42b is in contact with the outer peripheral surface of the energizing / blocking action portion 41. The fuse cover 41c is inserted into the outer periphery of the fuse cover 41c so as to be lower than the same height or the outer peripheral surface thereof.

  And each action | operation part attachment member 42 is arrange | positioned in the state in which the electricity interruption | blocking action | operation part 41 supported by it contacts the seam welding part 15 in the outer peripheral side contact part 7d of the heater pressing plate 7 through the downward open part 13, and the effect | action By connecting the end of the part mounting member 42 opposite to the side supporting the energizing / blocking action part 41 to the heat shield plate 12 with the screw 14, the energizing / blocking action part 41 is allowed to contact the outer periphery side of the heater pressing plate 7. It is attached to the outside of the storage container 1 in a state of being applied to the seam welded portion 15 in the contact portion 7d.

  In this manner, in the state where the energization cutoff action part 41 is attached by the action part attachment member 42, the conduction cutoff action part 41 (by the elastic biasing force of the metal forming the action part attachment member 42 (particularly, the main body part 42a). Specifically, the outer peripheral surface of the fuse cover 41c) is held in a state where it is applied to the outer peripheral abutting portion 7d of the heater pressing plate 7.

That is, in this embodiment, the heater pressing plate 7 is attached to the storage container 1 by fixing the outer peripheral contact portion 7d to the outer surface of the bottom portion 1B of the storage container 1 by seam welding, and cuts off the power supply. The current-carrying action part 41 constituting the means 40 is applied to the seam welded portion 15 fixed by seam welding to the outer surface of the bottom 1B of the storage container 1 at the outer peripheral side contact part 7d. become.
In addition, the energizing / interrupting action part 41 constituting the energizing / interrupting means 40 is attached to the heat shield plate 12 via the action part attaching member 42 in a state where the energizing / interrupting action part 41 is applied to the outer peripheral side contact part 7d of the heater pressing plate 7. Will be.

The temperature sensor 8 is composed of a thermistor, and as shown in FIG. 4, the temperature sensor 8 is a sensor at the bottom 1B of the storage container 1 via a sensor support member 1e fixed to the heat shield plate 12 with screws or the like. It is attached in contact with the outer surface of the mounting raised portion 1c.
That is, the temperature sensor 8 is configured to detect the temperature of the central portion on the outer surface of the bottom 1 </ b> B of the storage container 1 as the temperature of the water W in the storage container 1.

  In other words, in this embodiment, the temperature sensor 8 is provided so as to detect the temperature of the central portion on the outer surface of the bottom 1B of the storage container 1 as the temperature of the water W in the storage container 1, and the temperature sensor 8 at the bottom 1B of the storage container 1 An annular recess 1d (an example of a recess) is provided at a portion different from the temperature detection location by the temperature sensor 8 so that the inner surface of the bottom 1B of the storage container 1 is recessed downward. The heater pressing plate 7 is configured to include the outer peripheral side contact portion 7d corresponding to the portion corresponding to the annular recess 1d on the outer surface of the bottom portion 1B of the storage container 1, and the energization blocking means 40 (specifically Is applied to the outer peripheral contact portion 7d of the heater pressing plate 7 that is in contact with the portion corresponding to the annular recess 1d on the outer surface of the bottom 1B of the storage container 1. become.

  As shown in FIGS. 1 and 2, the operation unit 10 is configured as a panel type including a plurality of sheet-like switches, and is provided on the side peripheral surface of the case body 4. The plurality of switches provided in the operation unit 10 includes an operation switch 10a for instructing the operation and stop of the humidifier H, and the like.

Next, the lid 200 will be described.
As shown in FIGS. 2 and 3, the lid body 200 is provided with a steam channel 21 in a recessed shape, and a steam port cover mounted in a state of covering the upper opening of the steam channel 21. 22 is detachably provided, and a lid-side suction port 23 is provided on a side wall portion of the lid body 200 forming the vapor flow path 21. The steam port cover 22 is configured in a lattice shape having ribs in a grid pattern so as to be ventilated.
Further, as shown in FIGS. 1 and 2, the lid 200 is operated from above, and the lid opening / closing lever 24 for opening and closing the lid 200 and the lid 200 are closed. A lock knob 25 for holding is provided.

As shown in FIG. 2, the lid 200 is further provided with a steam ejection nozzle 26 and a reflux unit 27.
The vapor ejection nozzle 26 is composed of a flexible tube, and the one end opening communicates with the inside of the storage container 1 and the other end opening with the lid 200 attached to the outer case 100 in a closed state. Is provided so as to face the steam flow path 21. Although not shown in the drawings, the recirculation unit 27 has a recirculation hole that communicates the inside of the storage container 1 and the steam flow path 21 with the lid 200 attached to the outer case 100 in a closed state, and a recirculation thereof. And a reflux valve that opens and closes the hole.

  A case-side suction port 28 that communicates with the lid-side suction port 23 of the lid 200 is provided at the upper end of the exterior case 100 in a state where the lid 200 is attached to the opening 2 in a closed state.

A space having a predetermined volume is formed between the water surface Ws of the water W stored in the storage container 1 and the lower surface of the lid body 200 in a state where the lid body 200 is attached to the exterior case 100 in a closed state. The maximum storage capacity of the water W in the storage container 1 is set.
Then, as shown in FIG. 3, when water W is stored in the storage container 1 with a capacity equal to or less than the maximum storage capacity, and the lid 200 is attached to the exterior case 100 in a closed state, the water surface Ws in the storage container 1 is above. A vapor-filled space 29 that is closed by the lid 200 is formed. The recirculation valve constituting the recirculation part 27 closes the recirculation hole as the water W in the storage container 1 boils and steam is generated by the heating by the electric heater 6 and the internal pressure of the vapor filling space 29 increases. On the other hand, as the energization of the electric heater 6 is stopped, the generation of steam in the storage container 1 is stopped, and the internal pressure of the steam filling space 29 is lowered, the reflux hole is opened by its own weight. It is configured.

Then, when the electric heater 6 is energized and heated, the heat generated from the electric heater 6 is transferred to the water W in the storage container 1 via the bottom 1B of the storage container 1, and the water in the storage container 1 is transferred. W is heated to boil and steam is generated.
The steam thus generated fills the steam-filled space 29 and is jetted into the steam channel 21 through the steam jet nozzle 26 and passes through a plurality of holes in the steam port cover 22 to be humidified (external space). ).

Next, the control operation of the control unit 9 will be described.
Although illustration is omitted, a heater driving unit is provided that controls the heating operation of the electric heater 6 such as intermittent energization of the electric heater 6 and adjustment of power supplied to the electric heater 6. The control unit 9 is configured using a microcomputer, and is configured to control the heating operation of the electric heater 6 by controlling the operation of the heater driving unit.
When the start of the humidification operation is instructed by the operation switch 10a of the operation unit 10, the control unit 9 starts the humidification operation for heating the electric heater 6, and the operation switch 10a is instructed to stop the humidification operation. Then, the heating operation of the electric heater 6 is stopped and the humidifying operation is stopped.

  In the humidification operation, the controller 9 increases the temperature until the temperature detected by the temperature sensor 8 reaches a predetermined humidification temperature (eg, 94 ° C.) after the start of the humidification operation is commanded by the operation switch 10a of the operation unit 10. In the temperature process, the operation of the heater drive unit is controlled so as to supply predetermined power to the electric heater 6, and in the humidification process after the temperature detected by the temperature sensor 8 exceeds the humidification temperature, the electric heater is heated at a predetermined duty ratio. The operation of the heater drive unit is controlled so as to intermittently energize 6.

In addition, during the humidification operation, the control unit 9 causes the heater to cut off the power supply to the electric heater 6 when the temperature detected by the temperature sensor 8 becomes equal to or higher than the set temperature for stopping heating set higher than the humidification temperature. Control the operation of the drive.
Incidentally, the set temperature for stopping heating is higher by a predetermined temperature than the temperature of the portion corresponding to the sensor mounting raised portion 1c on the outer surface of the bottom 1B of the storage container 1 in a state where the water W in the storage container 1 is boiling. The temperature is set to 117 ° C., for example.
Also, the overheat prevention set temperature at which the temperature fuse constituting the energization cut-off acting part 41 is blown is set to a temperature higher than the heating stop set temperature, for example, 170 ° C.

That is, when the operation switch 10a is pushed without putting water into the storage container 1 and the humidification operation is started, or when the water in the storage container 1 runs out during the humidification operation, the detected temperature of the temperature sensor 8 When the temperature rises above the set temperature for stopping heating, the control of the control unit 9 automatically shuts off the power supply to the electric heater 6, operates the heating stop function, and prevents emptying.
Even if the temperature sensor 8, the control unit 9, the heater driving unit, etc. break down and the temperature detected by the temperature sensor 8 in the bottom 1 B of the storage container 1 exceeds the set temperature for stopping heating, the electric heater 6 Even if the heating operation of the electric heater 6 is continued without being interrupted, the temperature fuse is blown if the temperature fuse constituting the current interrupting action part 41 is heated to a temperature higher than the set temperature for preventing overheating. And since electricity supply to the electric heater 6 is interrupted | blocked, damage to the humidifier H by overheating can be prevented.

Here, the failure of the temperature sensor 8 may be a failure in which the temperature detection itself becomes impossible, a failure in which the temperature detection accuracy decreases in a direction in which the detected temperature is lower than the actual temperature, or the like.
Further, as a failure of the control unit 9 and the heater driving unit, a failure that impairs the function of cutting off the power supply to the electric heater 6 can be considered.

In particular, according to the present invention, the energization interruption action part 41 constituting the energization interruption means 40 is applied to the outer peripheral side abutting part 7d abutted on the outer surface of the bottom 1B of the storage container 1 in the heater pressing plate 7. Therefore, the heat transfer from the electric heater 6 to the energization interruption action part 41 of the energization interruption means 40 passes through the bottom part 1B of the storage container 1 and the outer peripheral side contact part 7d of the heater holding plate 7, This is performed by two paths, that is, a heat transfer path that passes only through the heater pressing plate 7.
And when the water W exists in the storage container 1, since the heat transferred from the electric heater 6 to the bottom 1B of the storage container 1 is absorbed by the water W in the storage container 1, the storage container 1 Heat transfer from the electric heater 6 to the energization interruption action part 41 in the heat transfer path passing through the bottom 1B and the outer peripheral side contact part 7d of the heater pressing plate 7 is suppressed, and the temperature rise of the energization interruption action part 41 is suppressed. Is suppressed. Therefore, even if the set temperature for preventing overheating is set so that the difference between the set temperature for stopping heating and the set temperature for stopping heating is as small as possible, when the water W is present in the storage container 1, Can be reliably maintained at a temperature lower than the set temperature for preventing overheating, and when the heating stop function can be operated normally, the energization of the electric heater 6 is erroneously interrupted by the energization interrupting means 40. Can be sufficiently prevented.

On the other hand, when there is almost no water W that is the heat absorption source of the electric heater 6 in the storage container 1 when the heating stop function is in an abnormal state, the energization shut-off action unit 41 becomes the bottom 1B of the storage container 1. And the heat of the electric heater 6 that is transferred through the heat transfer path that passes through the outer peripheral contact portion 7d of the heater pressing plate 7 and the heat of the electric heater 6 that is transferred through the heat transfer path that passes only through the heater pressing plate 7 Since it is heated, the energization cut-off action part 41 is set for overheating prevention after the temperature at the temperature detection point (the center part of the bottom part 1B) by the temperature sensor 8 in the bottom part 1B of the storage container 1 exceeds the set temperature for stopping heating. It will be heated to temperature rapidly, and interruption | blocking of electricity supply to the electric heater 6 can be speeded up.
Therefore, damage to the humidifier H due to overheating can be prevented.

In this embodiment, the two energization / blocking action portions 41 are respectively applied to the outer peripheral side abutting portions 7d located at portions facing each other across the central portion of the outer surface of the bottom portion 1B of the storage container 1. Is provided.
Thereby, when the storage container 1 is tilted because the humidifier H is tilted and installed, the heating stop function becomes inoperable. On the other hand, since the water W does not exist in the bottom part of the storage container 1 above the energization interruption operation part 41, the energization to the electric heater 6 can be quickly interrupted.

In addition, the energization cutoff action part 41 is applied to the outer peripheral side contact part 7d that is in contact with the part corresponding to the annular recess 1d on the outer surface of the bottom part 1B of the storage container 1.
Thus, when the humidifier H is installed at an inclination and the storage container 1 is inclined, the temperature sensor 8 at the bottom of the storage container 1 becomes small even if the amount of water W in the storage container 1 becomes small. In spite of the presence of water W at the temperature detection point due to the above, it is avoided as much as possible that the water W does not exist in the bottom portion of the storage container 1 above the energizing / blocking action portion 41, that is, the annular recess 1d. can do. Therefore, even if the set temperature for preventing overheating is set so that the difference from the set temperature for stopping heating is further reduced, the energization cut-off function is performed even though the detected temperature of the temperature sensor 8 is lower than the set temperature for stopping heating. It is possible to reliably avoid the portion 41 from being heated to the set temperature for preventing overheating.
Accordingly, when the humidifier H is inclined and the storage container 1 is inclined when the heating stop function can be operated normally, the energization is performed even if the amount of the water W in the storage container 1 becomes small. It is possible to more reliably prevent malfunctions in which energization of the electric heater 6 is erroneously interrupted by the interrupting means 40.

[Another embodiment]
(A) The specific configuration of the energization cutoff means 40 is not limited to the configuration illustrated in the above embodiment.
Specifically, a configuration provided with the temperature fuse as in the above-described embodiment as the energization interrupting action part 41 that acts to interrupt the energization to the electric heater 6 when it is heated above the set temperature for overheating prevention. Other configurations such as a one-shot type thermostat can be used.

In addition to the temperature sensor 8 and the control unit 9 in the above-described embodiment, a temperature sensor and a control unit dedicated to an abnormal time when the heating stop function is disabled due to their failure and a temperature dedicated to these abnormal times are provided. The power cut-off means 40 may be configured by a sensor and a control unit. Incidentally, the control unit dedicated to the abnormal time is also configured using a microcomputer.
In this case, the temperature sensor dedicated to the abnormal time is arranged in contact with the outer peripheral side contact portion 7d of the heater pressing plate 7, and the control unit dedicated to the abnormal time has a detection temperature of the temperature sensor dedicated to the abnormal time. When the temperature exceeds the set temperature for preventing overheating, the operation of the heater drive unit is controlled so as to cut off the power supply to the electric heater 6.

(B) The number, the arrangement form, and the arrangement place of the energization interrupting means 40 can be variously changed from the above embodiment.
For example, in the above-described embodiment, the two energization blocking means 40 are respectively applied to portions located on the opposite sides of the center of the bottom portion 1B of the storage container 1 in the outer peripheral side contact portion 7d of the heater pressing plate 7. Although it provided in the state attached, the space | interval in the circumferential direction of the bottom part 1B of the storage container 1 is put in the state which applied the 3 or more electricity supply interruption | blocking means 40 to the outer peripheral side contact part 7d of the heater pressing plate 7, respectively. You may arrange | position separately.
Further, one energization interruption means 40 may be disposed so as to abut against the outer peripheral side abutting portion 7 d of the heater pressing plate 7.
Further, one or a plurality of energization interrupting means 40 may be disposed in a state of being applied to the inner peripheral side contact portion 7 b of the heater pressing plate 7.

(C) When fixing the outer peripheral side contact portion 7d of the heater pressing plate 7 to the outer surface of the bottom portion 1B of the storage container 1, the fixing method is not limited to the seam welding exemplified in the above embodiment. . For example, when welding is used as the fixing method, spot welding or the like can be used in addition to seam welding.

(D) In bringing the outer peripheral side contact portion 7d of the heater pressing plate 7 into contact with the outer surface of the bottom portion 1B of the storage container 1, in the above embodiment, the outer peripheral side contact portion of the heater pressing plate 7 by seam welding or the like. 7d is fixed to the outer surface of the bottom 1B of the storage container 1, but the heater pressing plate 7 is elastically supported on the outer surface of the bottom 1B of the storage container 1 by the heat shield plate 12, and the elasticity of the heater pressing plate 7 causes the heater pressing plate You may comprise so that the outer peripheral side contact part 7d of 7 may contact | abut on the outer surface of the bottom part 1B of the storage container 1. FIG.

(E) The mode of disposing the energization cut-off acting portion 41 of the energization cut-off means 40 in a state of being applied to the outer peripheral side contact portion 7d of the heater pressing plate 7 is the form exemplified in the above-described embodiment, that is, the energization cut-off It is not limited to the form in which the action part 41 is attached to the heat shield plate 12 via the action part attachment member 42 in a state where the action part 41 is applied to the outer peripheral side contact part 7d of the heater pressing plate 7. For example, the configuration may be such that the energization cut-off acting portion 41 is directly attached to the heater pressing plate 7 by welding or a screw in a state where it is applied to the outer peripheral contact portion 7d of the heater pressing plate 7.

(F) As an example of the liquid heater to which the present invention is applicable, the liquid heater is not limited to the humidifier H illustrated in the above embodiment, and may be, for example, an electric pot or an electric kettle.
In the electric pot, the set temperature for stopping heating may be described as the temperature of the outer surface of the bottom 1B of the storage container 1 in a state where the water W in the storage container 1 is boiling (hereinafter referred to as boiling corresponding temperature). ) Is set to a temperature higher than the predetermined temperature, for example, 110 ° C. In the electric pot, the temperature for keeping warm can be changed and set, and in a normal boiling operation in which water is put into the storage container 1 and heated, the temperature detected by the temperature sensor 8 is at or near the boiling temperature. Then, the energization to the electric heater 6 is once interrupted, and thereafter the energization to the electric heater 6 is interrupted so as to maintain the temperature detected by the temperature sensor 8 at the temperature for keeping warm.
Incidentally, the electric kettle includes a kettle body provided with the storage container 1 and the electric heater 6 and a power supply plate for supplying electric power to the electric heater 6 of the kettle body.

  Note that the configuration disclosed in the above embodiment (including another embodiment, the same applies hereinafter) can be applied in combination with the configuration disclosed in the other embodiment as long as no contradiction occurs. The embodiments disclosed in this specification are exemplifications, and the embodiments of the present invention are not limited thereto, and can be appropriately modified without departing from the object of the present invention.

  As described above, at the time when the heating stop function can be operated normally, when the abnormality that the heating stop function becomes inoperable while preventing the malfunction that the energization to the electric heater is erroneously interrupted by the energization interruption means, It is possible to provide a liquid heater capable of speeding up the interruption of energization to the electric heater by the electricity interruption means.

1 storage container 1B bottom 1d annular recess (recess)
6 Electric heater 6h Sensor hole (opening)
7 Heater holding plate (Heater holding member)
7d Outer peripheral side contact part (contact part)
8 Temperature sensor (temperature detection means)
9 Control unit (control means)
12 Heat-shielding plate 40 Energization interruption means 41 Energization interruption action part 42 Action part attachment member (attachment member)
W Water (liquid)

Claims (4)

A bottomed cylindrical storage container for storing the liquid to be heated, a plate-shaped electric heater for heating the liquid in the storage container, and the electric heater are sandwiched and fixed between the outer surface of the bottom of the storage container. When the temperature of the heater holding member, the temperature detecting means for detecting the temperature of the liquid in the storage container, and the temperature detected by the temperature detecting means are equal to or higher than the set temperature for stopping heating to prevent emptying, the electric heater Control means for interrupting energization, and energization interruption for interrupting energization to the electric heater when heated above the set temperature for overheating prevention set higher than the set temperature for stopping heating by heat transfer from the storage container A liquid heater comprising means,
The heater holding member includes a contact portion that contacts the outer surface of the bottom of the storage container in a state where the electric heater is sandwiched and fixed between the electric heater and the outer surface of the bottom of the storage container.
The heater pressing member is attached to the storage container by fixing the contact portion to the outer surface of the bottom of the storage container by welding,
A liquid heater in which the energization shut-off means is disposed in a state of being applied to a portion of the contact portion fixed to the outer surface of the bottom portion of the storage container by welding or in the vicinity thereof . The electric heater is configured with an opening in the center,
The electric heater is provided in a state where the opening is positioned at the center of the outer surface of the bottom portion of the storage container and applied to the outer surface of the bottom portion,
The temperature detection means is provided so as to detect the temperature of the central portion of the outer surface of the bottom of the storage container as the temperature of the liquid in the storage container;
The heater pressing member is configured to cause at least the abutting portion to abut on portions facing each other across the central portion of the outer surface of the bottom portion in a region on the outer peripheral side of the outer surface of the bottom portion;
2. The liquid according to claim 1 , wherein at least two of the current-carrying-off means are provided in a state of being respectively applied to the abutting portions located at portions facing each other across the central portion of the outer surface of the bottom portion. Heater. The contact portion, a liquid heater of claim 1 or 2 is fixed to the outer surface of the bottom portion of the storage container by seam welding. A bottomed cylindrical storage container for storing the liquid to be heated, a plate-shaped electric heater for heating the liquid in the storage container, and the electric heater are sandwiched and fixed between the outer surface of the bottom of the storage container. When the temperature of the heater holding member, the temperature detecting means for detecting the temperature of the liquid in the storage container, and the temperature detected by the temperature detecting means are equal to or higher than the set temperature for stopping heating to prevent emptying, the electric heater Control means for interrupting energization, and energization interruption for interrupting energization to the electric heater when heated above the set temperature for overheating prevention set higher than the set temperature for stopping heating by heat transfer from the storage container A liquid heater comprising means,
The electric heater is configured with an opening in the center,
The electric heater is provided in a state where the opening is positioned at the center of the outer surface of the bottom portion of the storage container and applied to the outer surface of the bottom portion,
The temperature detection means is provided so as to detect the temperature of the central portion of the outer surface of the bottom of the storage container as the temperature of the liquid in the storage container;
The heater holding member includes a contact portion that contacts the outer surface of the bottom of the storage container in a state where the electric heater is sandwiched and fixed between the electric heater and the outer surface of the bottom of the storage container.
The heater pressing member is configured to cause at least the abutting portion to abut on portions facing each other across the central portion of the outer surface of the bottom portion in a region on the outer peripheral side of the outer surface of the bottom portion;
A liquid heater provided with at least two current-carrying-off means respectively applied to the abutting portions located at portions facing each other across the central portion of the outer surface of the bottom portion.

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