JP5009230B2 - Heating equipment - Google Patents

Description

  The present invention relates to a heating device such as an electric pot, a humidifier, and a rice cooker.

  This type of heating device includes a container that accommodates an object to be heated, and a heater is disposed as a heating unit in the container to heat the object to be heated via the container. Specifically, in an electric pot, water is accommodated as an object to be heated in a container, and the heater is operated to boil the water and keep it at a predetermined temperature. In the humidifier, water is accommodated as an object to be heated inside the container, and the heater is operated to boil the water and supply the steam to the room to humidify the room. In a rice cooker, rice and water are housed as objects to be heated inside a detachable container (pot), and the water is boiled by setting the container in the housing part (container) of the main body and operating the heater. Cook rice.

And in this heating apparatus, the said heater is arrange | positioned at the bottom of the container.
Japanese Patent Laid-Open No. 10-14768

  In the heating apparatus of Patent Document 1, in order to increase the amount of heating by the heater, the shape of the bottom heater becomes large, and thus a significant design change is required. Therefore, a configuration in which a new heater (body heater) is disposed on the side of the cylindrical container is conceivable.

  However, since the temperature fuse, which is a safety measure when the microcomputer breaks down (runaway), is provided on the bottom heater side, inconvenience occurs when the bottom heater and the body heater are connected in parallel. That is, in the state where the microcomputer is broken and the bottom heater is disconnected, the heat of the cylinder heater is difficult to be transmitted to the temperature fuse, and there is a possibility that peripheral resin parts are melted due to abnormal heating of the cylinder heater.

  Therefore, in this case, it is conceivable that a thermal fuse is provided in each connection line of the bottom heater and the body heater connected in parallel to the commercial power supply (power supply unit). However, in this case, even if one temperature fuse is blown (cut off), the other temperature fuse is not blown, so that the other heater continues to be heated.

  The present invention has been made in view of conventional problems, and it is an object of the present invention to provide a heating device that reliably prevents abnormal heating of a plurality of heaters connected in parallel and can also reduce the number of thermal fuses. is there.

In order to solve the above-described problem, the first heating device of the present invention has a container for storing an object to be heated inside the exterior body, and a heating means for heating the object to be heated is disposed in the container. In the heating apparatus, as the heating means, a first heater and a second heater having a smaller rated power than the first heater and connected in parallel with the first heater are disposed so as to contact the container. A pair of temperature fuses for preventing abnormal heating of the first and second heaters are provided in series on the upstream side of the branch connection portions of the first and second heaters connected in parallel, and one of the temperature fuses is connected. as well as disposed on the surface of the second heater has a configuration which is disposed the other of the temperature fuse to the surface of the first heater.
In this first heating device, the first heater is a bottom boiling heater disposed at the bottom of the container, and the second heater is a body boiling heater disposed at the side of the container. It is preferable.

In the second heating device of the present invention, as the heating means, a bottom heater at the bottom of the container and a body heater connected in parallel with the bottom heater at the side of the container are arranged in parallel. on the upstream side of the branch connection portion between the bottom heater and cylinder heater connected, interposed a pair of thermal fuses to prevent abnormal heating of the barrel heater and the bottom heater in series, the barrel of one of the temperature fuse While being arranged on the surface of the heater, the other temperature fuse is arranged on the surface of the bottom heater .
Here, the bottom heater and the trunk heater have different rated power (heating amount), and the bottom heater has a larger heating amount. The body heater includes a substantial heater in which a heating wire is wound around a mica plate and a member for disposing the heater.

In the first and second heating devices configured as described above, when abnormal heating occurs in a state where the first (bottom) heater is disconnected , the first (bottom) heater is overheated due to continued heating of the second (trunk) heater. The temperature fuse is melted and the second (body) heater cannot be heated. When abnormal heating occurs in the state where the second (cylinder) heater is disconnected, the other temperature fuse is melted due to overheating due to the first (bottom) heater being continuously heated. The heater cannot be heated. If the other temperature fuse is not melted (cut off) for some reason, the overheating due to the first (bottom) heater being continuously heated is transferred to one temperature fuse, thereby causing one temperature The fuse melts and the first (bottom) heater cannot be heated.

Thus, according to the heating device of the present invention, when the first (bottom) heater and the second (body) heater connected in parallel are in an abnormal heating state, it is possible to reliably make the heating impossible. It is. Further, it is possible to prevent abnormal heating of both the heater at one temperature fuse, can reduce the number of installed thermal fuse, it is possible to reduce the cost.

In the first and second heating devices, it is preferable that the capacity of the one temperature fuse is smaller than the capacity of the other temperature fuse .

Further, it is preferable that a mounting bracket for holding the temperature fuse is provided, and the mounting bracket is fastened integrally with a fixing bracket for fixing the heater to the container with a screw. In this way, it is possible to improve the mounting workability of the thermal fuse.

In this case, the mounting bracket is made of a metal plate having elasticity, and includes a holding portion that holds the thermal fuse and a mounting portion that is fixed to the fixing bracket, and the holding portion is attached to the fixing bracket. In the attached state, it is preferable to elastically urge toward the heater . In this way, the heat of the heater can be reliably detected by the thermal fuse.

The heating apparatus of the present invention, since the disposed interposed a pair of thermal fuse in series on the upstream side of the branch connection portions of the pair of heaters connected in parallel, each thermal fuse on the surface of each heater, reliably Abnormal heating of the heater can be prevented .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows an electric pot that is a heating device according to an embodiment of the present invention. In this electric pot, a container 22 for containing water to be heated is disposed in the exterior body 10, the water in the container 22 is heated by a plurality of boiling heaters 34, 44, and the hot water supply pump 26 is turned on. By operating it, hot water is discharged from the discharge part 30 through the pumping pipe 28.

  The exterior body 10 includes a cylindrical body 11, a shoulder body 17 attached to an upper portion of the body 11, and a lid body 21 attached to the shoulder body 17 so as to be opened and closed.

  The lower end opening of the body 11 is closed by the lower plate 12. Further, the body 11 is provided with a nose portion 13 projecting outward on the front surface, and an ejection opening portion 14 opened downward near the tip thereof. Further, a rectangular opening 15 is provided on the front side of the body 11, and a transparent window member 16 capable of seeing through the inside is disposed in the opening 15.

  The shoulder body 17 has a lower end shape that coincides with the upper end opening of the body 11, and a hinge connection portion 18 for attaching the lid body 21 so as to be detachable and rotatable is provided on the back side thereof. The shoulder body 17 has a shape in which a portion located above the nose portion 13 is curved downward toward the tip, and an operation panel portion 19 is provided at that portion. On the back side of the operation panel portion 19, a lid disposing portion 20 that is recessed downward is provided, and an opening (not shown) that exposes the inside of the container 22 is provided in the lid disposing portion 20. .

  The lid body 21 has the same shape as the lid arrangement portion 20 of the shoulder body 17 and is pivotally attached to the hinge connection portion 18 so as to seal the upper end opening of the container 22 so as to be opened and closed. The lid body 21 is provided with an operation member (not shown) that is locked to the shoulder body 17 so as not to be opened and is unlocked by an opening operation.

  The container 22 is made of metal (stainless steel (SUS436L)) including a cylindrical container body 23 attached to the opening of the shoulder body 17 and a container bottom body 24 that closes the lower end opening of the container body 23. It is. The container bottom body 24 is provided with a connection hole 25 for connecting a hot water supply pump 26. The hot water supply pump 26 is connected to a pumping pipe 28 located behind the window member 16 via a joint member 27 having a substantially L shape. Further, a valve set 29 for preventing water leakage at the time of falling is connected to the upper end of the pumping pipe 28, and a discharge unit 30 disposed in the discharge opening 14 is provided in the valve set 29. . Further, the container 22 is provided with a heater mounting portion 31 that is recessed upward toward the inside of the container 22 at a position excluding the connection hole 25 in the container bottom body 24, and further has a circular shape at the center of the heater mounting portion 31. Thus, a sensor arrangement portion 32 that is recessed upward is provided.

  A bottom heater unit 33 is disposed in the heater mounting portion 31 of the container 22 as a heating means for boiling and keeping warm the water stored in the container 22. Moreover, the container 22 of this embodiment is further provided with a body heater unit 43 as a heating means for boiling water on the outer periphery of the container body 23 which is the lower end of the side part. In addition, the trunk | drum heater of this invention contains the trunk | drum heater unit 43 containing the substantial trunk | boiling boiling heater 44 mentioned later.

  As shown in FIG. 2, the bottom heater unit 33 includes a bottom boiling heater 34, a bottom heat retaining heater 35, an insulating plate 38 that insulates the heaters 34 and 35, and both ends, and a heater in which these are stacked inside. And a cover 39. The bottom boiling heater 34 is operated (energized) during boiling processing, and can output 905 W, for example. The bottom heat retaining heater 35 is operated during the heat retaining process, and can output 65 W, for example. These heaters 34 and 35 are obtained by winding a nichrome wire 37 (heating wire) around a mica plate 36 having a through hole 36a in the center. The insulating plate 38 is a mica plate having a through hole 38a at the center. The heater cover 39 is made of metal (aluminum) and serves as a heat radiating plate that averages the heat generated by the internal heaters 34 and 35 and supplies the heat to the container bottom 24, and has a shape slightly smaller than the heater mounting portion 31. A base plate portion 40 is formed, and three bent plate portions 41a, 41b, and 41c that are substantially the same shape as the base plate portion 40 when bent. And this bottom heater unit 33 is arrange | positioned so that it may accommodate in the heater attachment part 31, and the surface (bottom side) is joined by the metal coating | coated member 42 so that it cannot detach | leave.

  As shown in FIG. 3, the body heater unit 43 includes a body boiling heater 44 having a rectangular (band) shape, a holding frame 47 having a C shape in plan view, and a protective member 51 that protects the body boiling heater 44. It has. The body boiling heater 44 is operated at the time of boiling processing. For example, the body boiling heater 44 can output 295 W so as to be 1200 W together with the bottom boiling heater 34. The body boiling heater 44 is formed by winding a nichrome wire 46 (electric heating wire) so as to form a spiral shape around a plate-like mica plate 45. The holding frame 47 is made of metal (aluminum) and serves as a heat radiating plate, and has a substantially C-shaped cross section including an inner surface portion 48, an outer surface upper frame portion 49, and an outer surface lower frame portion 50. The protection member 51 is made of metal (iron) and has a diameter slightly smaller than the outer shape of the container body 23. At both ends of the protective member 51, to-be-tightened portions 52A and 52B having screw insertion grooves 52a punched out so as to form a U shape from the front end edge are provided so as to protrude outward. Further, the protective member 51 is provided with an exposure hole 53 for exposing the connecting portion 46a of the body boiling heater 44 located inside.

  As shown in FIGS. 4 and 5, the body heater unit 43 is mounted by being screwed to the lower end of the side portion of the container 22 by a fixing metal 54. As shown in FIG. 6, the fixing bracket 54 includes a pair of plate-like members 55 and 60. The first plate-like member 55 has an L shape in a plan view having an insertion portion 56 having an insertion hole 56 a for inserting a screw and a cover portion 57 bent from the outer edge of the insertion portion 56. A pair of protruding pieces 58 are provided on the inner end edge of the insertion portion 56 so as to protrude inward. A washer plate 59 is fixed to the outer surface of the insertion portion 56. The second plate-shaped member 60 is a rectangular shape having the same shape as the insertion portion 56. The second plate member 60 is provided with a screw hole 61 for tightening the screw 71. Similarly to the first plate-like member 55, a pair of projecting pieces 62 are provided on the inner edge so as to protrude inward.

  In this embodiment, as shown in FIGS. 4 and 5, a temperature fuse 80 </ b> A for preventing abnormal heating of the body heater unit 43 and the bottom heater unit 33 on the surface of the body heater unit 43 is fixed to the fixing metal 54. The mounting bracket 63 for arranging the two is integrally attached by tightening. As shown in FIG. 6, the mounting bracket 63 holds the thermal fuse 80A and is made of an elastic metal (stainless steel) plate. The mounting bracket 63 includes a holding portion 64 that holds the temperature fuse 80 </ b> A, and a mounting portion 69 that is fixed to the fixing bracket 54. The holding portion 64 includes a curved plate portion 65 that is curved with a smaller curvature than the outer shape of the container 22 and that is shorter than the dimension from one tightened portion 52 </ b> A of the protective member 51 to the exposure hole 53. A pair of holding pieces 66, 66 that are curved in the same bending direction and with a smaller curvature than the outer shape of the thermal fuse 80A are provided on both side edges of the curved plate portion 65. Further, a bent portion 67 for inserting and holding the thermal fuse 80A is provided at the tips of the holding pieces 66. Further, a pressing piece 68 curved with the same curvature is provided at an intermediate position between the holding pieces 66 and 66 in order to prevent the thermal fuse 80A from being deformed outward and being separated from the surface of the body heater unit 43. It has been. The attachment portion 69 is bent so as to protrude outward in the substantially radial direction of the curved plate portion 65 from the end of the curved plate portion 65 opposite to the holding piece 66. Similar to the screw insertion groove 52 a of the protection member 51, the attachment portion 69 is provided with a screw insertion groove 70 punched out so as to form a U shape from the tip edge.

  The mounting bracket 63 is positioned so that the mounting portion 69 overlaps the tightened portion 52A in a state where the body heater unit 43 is positioned at a predetermined position on the side portion of the container 22. Then, the fixing fitting 54 in a state where the screw 71 is temporarily tightened with respect to the pair of plate-like members 55 and 60 is disposed from the outside, and the screw 71 is inserted into the insertion grooves 52 a and 70. In this state, the screw 71 is tightened. As a result, the pair of to-be-clamped portions 52A and 52B are brought close to each other, and the barrel boiling heater 44 and the holding frame 47 located on the inner side are brought into pressure contact with the side portion of the vessel 22 to thereby bring the barrel heater unit 43 into the vessel 22. Fix against. At the same time, the mounting portion 69 of the mounting bracket 63 is tightened, so that the curved plate portion 65 having a small curvature with which the holding piece 66 contacts the protective member 51 is attached in a state of being elastically deformed outward. Thereby, the temperature fuse 80 </ b> A held in the holding portion 64 is elastically biased toward the protection member 51 that covers (protects) the trunk boiling heater 44. Further, the temperature fuse 80 </ b> A held by the holding portion 64 is a portion of the protective member 51 where the body boiling heater 44 is not provided, that is, the nichrome wire 46 constituting the body boiling heater 44, depending on the size setting of the holding portion 64. It arrange | positions so that it may not be located on.

  As shown in FIG. 1, the thermistor 72, which is a temperature detecting means for detecting the internal water temperature via the container 22, passes through the bottom heater unit 33 and the sensor is disposed in the electric pot configured as described above. It arrange | positions so that the part 32 may be contacted. Further, a bottom heat shielding member 73 is disposed between the container 22 and the bottom of the exterior body 10 so as to cover the bottom of the container 22 so as to block heat of the bottom heater unit 33 with respect to the control board case 74. It is composed. Further, between the container 22 and the side portion of the exterior body 10, a body heat shield member 75 is disposed so as to cover the container body 23, and the heat of the body heater unit 43 with respect to a nearby resin product such as the pumping pipe 28. Is configured to shut off.

  In addition, a control board 76 including a power supply unit is disposed in the control board case 74, and a boiling process, a re-boiling process, and the like are performed according to a program stored in advance by a microcomputer 77 that is a control means mounted on the control board 76. Thermal insulation processing is executed. Specifically, as shown in FIG. 7, the microcomputer 77 detects that the user has connected the power cord to the commercial power source 79, or the user adds water during the heat retaining process by the thermistor 72. When a temperature drop of 10 ° C. or more is detected, the boiling process is performed, and then the heat retaining process is performed. Further, the re-boiling process is executed in accordance with the switch operation of the operation panel unit 19, and then the heat retaining process is executed. Further, the hot water supply pump 26 is operated according to the switch operation to execute the hot water supply process. Needless to say, the AC power from the commercial power supply 79 is rectified and converted into DC power by a power supply unit (not shown) and supplied to each component.

  Further, the boiling process including re-boiling is executed by supplying electric power from the commercial power source 79 to the boiling heaters 34 and 44 by outputting an ON signal to the relay 78A as switching means. Similarly, the heat retention process is executed by supplying an electric power from the commercial power supply 79 to the bottom heat retaining heater 35 by outputting an ON signal to the relay 78B.

In the present embodiment, a pair of thermal fuses 80A and 80B are interposed in series between the relays 78A and 78B and the commercial power source 79. That is, these thermal fuses 80A and 80B are connected to the bottom boiling heater 34 and the trunk boiling heater 44, which are connected in parallel with the relay 78A as a branch connection, upstream of the branch connection and connected in parallel. 34 and 44 and the bottom warming heater 35 are interposed in series upstream of the branch connection portion. One temperature fuse 80 </ b> A is disposed on the surface of the body heater unit 43 by the mounting bracket 63. The other temperature fuse 80 </ b> B is disposed so as to be positioned on the surface of the bottom heater unit 33. In this embodiment, the body boiling heater 44 is configured with a rated power of 295 W, and the bottom boiling heater 34 is configured with a rated power of 905 W. Therefore, each of the thermal fuses 80A and 80B is a thermal fuse. The one having a capacity smaller than 80B is applied.

  In the electric pot configured as described above, when the boiling process or the re-boiling process is performed in a state where the bottom boiling heater 34 and the trunk boiling heater 44 are not disconnected, the heats of both the boiling heaters 34 and 44 are combined. Heat is transferred to the thermal fuses 80A and 80B. Specifically, the heat of the trunk boiling heater 44 is transferred to the thermal fuse 80A through the protective member 51, and the heat of the bottom boiling heater 34 is transferred through the container 22, the holding frame 47, and the protective member 51. Be heated. The heat of the bottom boiling heater 34 is transferred to the temperature fuse 80B through the bottom heat retaining heater 35, the insulating plate 38, the heater cover 39 and the covering member 42, and the heat of the trunk boiling heater 44 is transferred to the container 22 and the heater. Heat is transferred through the cover 39 and the covering member 42.

  In this state, when the boiling heaters 34 and 44 are abnormally heated due to a failure of the microcomputer 77 or the like, the thermal fuse 80A having a small capacity is melted by the heat of both the boiling heaters 34 and 44. Thereby, since electric power supply is interrupted | blocked from the commercial power supply 79, both the boiling heaters 34 and 44 cannot be heated.

  If abnormal heating occurs while the bottom boiling heater 34 is disconnected, the temperature fuse 80A is melted due to overheating caused by continued heating of the body boiling heater 44, and the body boiling heater 44 cannot be heated. .

  Further, when abnormal heating occurs in the state where the trunk boiling heater 44 is disconnected, the temperature fuse 80B is melted due to overheating caused by continuing heating of the bottom boiling heater 34, and the bottom boiling heater 34 cannot be heated. . If the temperature fuse 80B is not melted (cut off) for some reason, overheating due to the continued heating of the bottom boiling heater 34 has a small capacity via the container 22, the holding frame 47, and the protective member 51. By transferring heat to the thermal fuse 80A, the thermal fuse 80A is melted and the bottom boiling heater 34 cannot be heated.

  As described above, according to the heating device of the present invention, when the bottom boiling heater 34 and the trunk boiling heater 44 connected in parallel are in an abnormal heating state, the thermal fuses 80A and 80B can reliably make the heating impossible. Is possible. Specifically, when all the boiling heaters 34 and 44 are normal, abnormal heating can be prevented by the temperature-side fuse 80A. Further, when an abnormality (disconnection) occurs in the bottom boiling heater 34, abnormal heating can be similarly prevented by the temperature-side fuse 80A. Further, when an abnormality occurs in the body boiling heater 44, basically, abnormal heating is prevented by the temperature fuse 80B on the bottom side, and even if an abnormality occurs in the temperature fuse 80B, the body side is surely secured. Abnormal heating can be prevented by the temperature fuse 80A. That is, abnormal heating can be reliably prevented with one thermal fuse 80A, so the number of thermal fuses installed can be reduced, and the cost can be reduced. In other words, the thermal fuse 80B on the bottom side is necessary for quickly stopping abnormal heating in view of safety, but is not necessarily provided.

  Further, in the above-described embodiment, the thermal fuse 80 </ b> A is disposed so as not to be positioned on the nichrome wire 46 constituting the body boiling heater 44, so that the heat of the body boiling heater 44 is not directly received. Therefore, the thermal fuse 80A can be surely blown only during abnormal heating.

  Further, since the temperature fuse 80A is integrally attached by the fixing metal 54 for fixing the trunk heater unit 43 while being held by the attachment metal 63, the mounting workability can be improved. In addition, the mounting bracket 63 is made of a metal plate having elasticity, and in the mounted state, the temperature fuse 80A is configured to be elastically biased toward the body boiling heater 44, so that the heat of the body boiling heater 44 is increased. Of course, the heat of the bottom boiling heater 34 can be reliably detected by the temperature fuse 80A through the container.

  In addition, the heating apparatus of this invention is not limited to the structure of the said embodiment, A various change is possible.

  For example, in the above-described embodiment, the thermal fuse 80A is disposed so as to be located at a portion where the body boiling heater 44 is not disposed by the mounting bracket 63, but is located between the adjacent nichrome wires 46 and 46 in FIG. You may arrange | position so.

  Moreover, in the said embodiment, although the electric kettle was mentioned as an example as an apparatus which adds the trunk | drum heater 44, any heating apparatus which attaches a heater to the container 22, such as a humidifier and a rice cooker, is applicable. Similar actions and effects can be obtained.

It is sectional drawing which shows the electric pot which is a heating apparatus which concerns on embodiment of this invention. It is a disassembled perspective view which shows the heater arrange | positioned at the bottom of a container. It is a disassembled perspective view which shows the heater arrange | positioned at the side part of a container. It is a front view which shows the state which has arrange | positioned the trunk | drum heater to the container. FIG. 5 is a partially enlarged bottom view of FIG. 4. FIG. 5 is a partially enlarged exploded perspective view of FIG. 4. It is a block diagram which shows the structure of an electric pot.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Exterior body 22 ... Container 33 ... Bottom heater unit 34 ... Bottom boiling heater (1st boiling heater)
35 ... bottom insulation heater 43 ... body heater unit 44 ... body boiling heater (second boiling heater)
47 ... Holding frame 51 ... Protective member 54 ... Fixing bracket 63 ... Mounting bracket 64 ... Holding portion 69 ... Mounting portion 78A, 78B ... Relay 80A, 80B ... Thermal fuse

Claims (6)

In a heating apparatus in which a container for storing an object to be heated is disposed inside the exterior body, and heating means for heating the object to be heated is disposed in the container.
As the heating means, a first heater and a second heater having a rated power smaller than that of the first heater and connected in parallel with the first heater so as to come into contact with the container,
A pair of temperature fuses for preventing abnormal heating of the first and second heaters are interposed in series on the upstream side of the branch connection portion of the first and second heaters connected in parallel.
One heating fuse is disposed on the surface of the second heater, and the other thermal fuse is disposed on the surface of the first heater .   The said 1st heater is a bottom boiling heater arrange | positioned at the bottom of the said container, A said 2nd heater is a trunk | boiler boiling heater arrange | positioned at the side part of the said container. Heating equipment. In a heating apparatus in which a container for storing an object to be heated is disposed inside the exterior body, and heating means for heating the object to be heated is disposed in the container.
As the heating means, a bottom heater at the bottom of the container and a body heater connected in parallel with the bottom heater at the side of the container,
A pair of temperature fuses for preventing abnormal heating of the trunk heater and the bottom heater are connected in series on the upstream side of the branch connection portion of the bottom heater and the trunk heater connected in parallel.
One heating fuse is arranged on the surface of the body heater, and the other temperature fuse is arranged on the surface of the bottom heater . The heating apparatus according to any one of claims 1 to 3 , wherein a capacity of the one temperature fuse is smaller than a capacity of the other temperature fuse .   The mounting bracket for holding the thermal fuse is provided, and the mounting bracket is attached to the fixing bracket for fixing the heater to the container by being integrally tightened with a screw. Item 5. The heating device according to any one of items 4 to 4.   The mounting bracket is made of an elastic metal plate, and includes a holding portion that holds the thermal fuse, and a mounting portion that is fixed to the fixing bracket, and the holding portion is attached to the fixing bracket. The heating device according to claim 5, wherein the heating device is elastically biased toward the heater.

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