JP4987094B2 - Electric appliances - Google Patents

Description

  The present invention relates to an electrical product configured to prevent the spread of fire due to ignition of electrical wiring and electrical components.

  Conventional electric products are provided with a flame retardant layer on the inner surface of the upper half of the outer body made of synthetic resin, and on the bottom plate connected to the upper half of the control circuit board, hot air fan, etc. Electrical equipment, electrical wiring, etc. are provided. In the unlikely event of an ignition from an electrical device or electrical wiring in the outer body, the fire spread to the surroundings due to the fire is suppressed by the flame retardant layer provided in the upper half of the outer body (see, for example, Patent Document 1).

JP 2004-147858 A (page 3-4, FIG. 2)

  In the above-mentioned conventional electrical products, a flame retardant layer is formed by applying a paint containing aluminum hydroxide to the inner surface of the upper half of the outer body made of synthetic resin. When the tracking phenomenon occurred on the side and the electric device or the wiring ignited toward the bottom surface, there was a possibility that the outer body and the fire spread from the outer body to the surrounding members. In addition, when a fire occurs and burns, it is difficult to determine whether the source of ignition is on the inner side of the outer body or on the outer side of the outer body from the leftovers etc. was there.

  The present invention has been made to solve the above-described problems, and can prevent the spread of fire even if the circuit components on the power supply board or the electrical wiring connected to the power supply board ignite by any chance, and the ignition source. An object of the present invention is to provide an electrical product that makes it possible to determine whether or not a device is inside.

  An electrical product according to the present invention includes a power supply board on which a circuit component for supplying a voltage necessary for the electrical component is mounted, and an enclosure that houses the power supply board, and the enclosure includes a metal plate as an outer body. And a plate material comprising a coating film coated with an inorganic material inside the metal plate.

According to the electrical product according to the present invention, the outer body of the enclosure is composed of a metal plate and a plate material that is coated with an inorganic material on the inner side of the metal plate. Even if the circuit component is ignited or the power supply substrate is ignited due to a tracking phenomenon caused by the charged part, it is possible to reliably prevent the fire from spreading from the enclosure to the surrounding components, thereby improving safety.
Moreover, according to the electrical product which concerns on this invention, since the outer body is comprised from the metal plate, even if a fire occurs, it remains. And the film coated on the inside of the metal plate has different shapes of cracks in the film when directly exposed to fire and when heated through the metal plate. Based on this, it is possible to determine whether or not the ignition source is in the enclosure.

It is a side view which cut | disconnects and shows a part of side of the rice cooker which is an example of the electric product which concerns on Embodiment 1 of this invention. It is the perspective view which showed the external appearance of the enclosure of FIG. It is the longitudinal cross-sectional view which expanded and showed the enclosure of FIG. It is a fragmentary sectional view of the enclosure of FIG. It is a figure which shows the effect of the enclosure of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a side view showing a side portion of a rice cooker that is an example of the home appliance according to Embodiment 1 of the present invention.
The rice cooker of FIG. 1 is comprised by the main body 1 in which an inner pot is detachably accommodated, and the cover body 2 which opens and closes the upper opening of the main body 1. FIG. An operation display unit 3 having various key switches, a liquid crystal display, LEDs, and the like necessary for rice cooking is provided on the open / close side surface (upper front surface) of the lid 2 of the main body 1. In the main body 1, there are provided an operation display board 4 disposed opposite to the operation display section 3, an enclosure 6 containing a power supply board 5, a heating coil (not shown) for induction heating the inner pot, and the like. .

The power supply board 5 includes a rectifier circuit and a smoothing capacitor for converting the AC voltage of the commercial power source to DC and smoothing, an inverter circuit for converting the DC voltage smoothed by the smoothing capacitor into a high frequency voltage, and a control voltage from the AC voltage of the commercial power source Various components that constitute a constant voltage circuit or the like for generating the signal are mounted.
The enclosure 6 is fixed to the bottom 7 in the main body 1.

2 is a perspective view showing an appearance of the enclosure of FIG. 1, and FIG. 3 is a longitudinal sectional view showing the enclosure of FIG. 1 in an enlarged manner.
The enclosure 6 includes a cover 60 located on the front side of the main body 1 and a box body 61 whose front opening is covered by the cover 60, and the outer shape is formed in a rectangular parallelepiped shape. A plurality of bosses 62 formed integrally with the rear surface of the box 61 are attached to the rear surface of the box body 61. Each of the plurality of bosses 62 is provided with a screw hole. The power supply board 5 is fixed to the rear surface side of the box body 61 by a set screw 70 screwed into the screw hole of the boss 62.

  Connection from the outside to the power supply substrate 5, connection from the power supply substrate 5 to the heating coil, and connection between the power supply substrate 5 and the operation display substrate 4 are performed via a connector 71 and a lead wire 72. As shown in FIG. 3, for example, the lead wire 72 is drawn out through a lead-out hole 73 provided on the right side surface of the enclosure 61 on the joint side when viewed from the cover 60 of the enclosure 6. The lead-out hole 73 of the lead wire 72 is a hole that is slightly larger than the size in which the lead wires 72 are bundled. The gap between the lead wire 72 and the lead-out hole 73 is made as small as possible, and sealing is performed so that air is blocked from entering and exiting so that the airtightness of the space in the enclosure 6 is maintained.

FIG. 4 is a cross-sectional view of the cover 60 and the box 61 of the enclosure.
The enclosure 6 is composed of the cover 60 and the box 61 as described above. And the board | plate material 80 which comprises them is comprised from the steel plate 81 and the membrane | film | coat 82 formed by coating the inorganic material inside the steel plate 81. FIG. As the inorganic member, for example, any of a silicate compound, a calcium compound, a magnesium compound, an aluminum compound, or a mixture thereof is used. As the flame retardant grade of the material, UL94_V0 or more is desirable. Further, the thicker the coating 82, the greater the heat resistance effect. However, in consideration of cost effectiveness, the thickness is preferably 0.5 mm to 2.0 mm.

FIGS. 5A and 5B are views showing the crack shape of the coating (inorganic material) at the time of fire of the enclosure 6 configured as described above.
FIG. 5A shows the shape of a crack when the inside of the enclosure 6 becomes a fire source and the coating 82 is directly exposed to a flame (internal fire).
FIG. 5B shows the shape of a crack when there is a fire source outside the enclosure 6 and the coating 82 is heated from the outside.
As is clear from the comparison between FIGS. 5A and 5B, the crack shape is small in the case of internal fire, and the crack shape is large in the case of external fire.
When a fire occurs, based on the shape of such a crack, it can be determined whether the inside of the enclosure 6 is a fire source or the outside of the enclosure 6 is a fire source.

  As described above, in the first embodiment, the airtightness of the space in the enclosure 6 is maintained, and the air entry and exit is blocked. Therefore, even if a circuit component mounted on the power supply board 5 is ignited or a tracking phenomenon occurs between different polarities of the power supply pattern of the power supply board 5 and the power supply board 5 is ignited, an oxygen deficient state occurs. The combustion of circuit components can be suppressed.

Further, since the outer body of the enclosure 6 is composed of the steel plate 81, it is possible to reliably prevent the fire from spreading from the enclosure 6 to the surrounding parts regardless of the direction in which ignition occurs, and to improve safety. .
In addition, a coating 82 formed by coating an inorganic material is provided on the inner side of the steel plate 81. When a fire occurs, the shape of the crack in the coating 82 (see FIGS. 5A and 5B). It is possible to determine whether it is an internal fire or an external fire.

  As an application example of the electric product of the present invention, a rice cooker has been described as an example, but the present invention is also applied to an enclosure of a power supply board of an electric product such as an air purifier, a dehumidifier, a vacuum cleaner or an air conditioner. Is done.

  1 body, 2 lid, 3 operation display section, 4 operation display board, 5 power supply board, 6 enclosure, 7 bottom part, 60 cover, 61 box, 62 boss, 70 set screw, 71 connector, 72 lead wire, 73 drawer Hole, 80 plate material, 81 steel plate, 82 coating.

Claims (2)

A power supply board on which circuit components for supplying voltages necessary for electrical components are mounted;
An enclosure containing the power supply board,
The enclosure is
An electrical product, characterized in that the outer body is composed of a plate material comprising a metal plate and a film in which an inorganic material is coated on the inside of the metal plate.   The electrical product according to claim 1, wherein the inorganic material is any one of a silicate compound, a calcium compound, a magnesium compound, and an aluminum compound, or a mixture thereof.

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