WO2006030726A1 - Hot air heater - Google Patents

Abstract

A hot air heater includes heating wires (3a, 3b) wound around an insulating fire-resistant support in such a way that currents flow reversely through the heating wires (3a, 3b) in order to compensate electromagnetic waves generated from the heating wires (3a, 3b), thus reducing electromagnetic waves.

Description

 Specification

 Hot air heater

 Technical field

 The present invention relates to a warm air heater such as a hair dryer or a desktop warm air heater.

 Background art

 [0002] Conventionally, a hot-air heater in which a heating wire such as a nichrome wire is wound around an insulating refractory support formed of a myrtle plate or the like is generally known.

[0003] Further, there is also known a hot air heater in which a carbon molded body is additionally attached to a hot air outlet and a far infrared radiation effect is added by the carbon molded body (for example, Patent Document 1). Patent Document 1: Utility Model Registration No. 3011964

 Disclosure of the invention

 Problems to be solved by the invention

[0004] In general, electromagnetic waves are classified into radio waves, infrared rays, visible rays, ultraviolet rays, X-rays, and gamma rays wavelengths in order from the longer wavelength (that is, the lower frequency), and the photon energy increases as the wavelength decreases. When visible light or ultraviolet light hits a substance, it causes a chemical reaction and alters the substance, and strong ultraviolet light, X-rays, and gamma rays have an adverse effect on the body. An electromagnetic wave having a wavelength longer than that of infrared rays generally does not cause a chemical reaction, but if the intensity is high, the substance generates heat. Although it is not clear whether the wavelength longer than infrared rays and electromagnetic waves (radio waves) affect the human body, in recent years, research has been conducted on the effects of certain types of radio waves on the human body. In some cases, as in Sweden, when the frequency is 2 to 2000 Hz and the separation distance is 50 cm, the electric field is regulated to 0.025 kV / m or less and the magnetic field is regulated to 2.5 mG or less (SWEDISH BOARD FOR TECHNICAL ACCREDITATION G UIDELINE: MPR2) ₀ in the conventional general hairdryer is that by generating a magnetic field of about 70mG at a distance of 50 cm. Also, malfunctions due to electromagnetic waves have been reported for electronic devices such as semiconductors and pacemakers.

[0005] On the other hand, a hot air heater in which a carbon molded body is attached to a hot air outlet in order to enhance the infrared radiation effect is said to cause an increase in price because the carbon molded body itself is expensive. There was a problem.

 [0006] Therefore, a main object of the present invention is to provide a warm air heater capable of reducing certain types of electromagnetic waves.

 [0007] In addition, an object of the present invention is to provide a hot-air heater that can increase infrared radiation efficiency at a low cost.

 Means for solving the problem

 [0008] In order to achieve the above object, a hot air heater according to the present invention is a hot air heater in which a heating wire is wound around an insulating refractory support, and includes an input line and an output line of a power supply line. The heating wire connected in series or in parallel with the heating wire is connected to the insulated refractory support so that the current flowing through the heating wire is reversed so as to cancel out electromagnetic waves generated from the heating wire. It is characterized by being wound.

 [0009] In the hot air heater according to the present invention described above, the first heating wire and the second heating wire are connected in parallel between the input line and the output line of the power supply line, and the first heating wire and the second heating wire are connected. The heating wire is alternately directed in the same direction around the insulating refractory support so that the currents flowing through the first heating wire and the second heating wire are reversed in order to cancel electromagnetic waves generated from the heating wire. And the adjacent 1st heating wire and 2nd heating wire may be wound by the equivalent winding diameter.

 [0010] In order to achieve the above object, the hot air heater according to the present invention described above is characterized in that a ceramic honeycomb structure is provided on the downstream side of the hot air of the heating wire.

[0011] The ceramic honeycomb structure is coated with carbon powder, and the ceramic honeycomb structure with the coating has an emissivity of 0.8 or more in the entire infrared wavelength region. It is preferable that

[0012] The emissivity in the total infrared wavelength region of the ceramic honeycomb structure to which the coating is applied is preferably 0.9 or more.

[0013] The coating containing the carbon powder is preferably an impregnation coating.

[0014] The ceramic honeycomb structure is preferably disposed in the vicinity of the heating wire.

[0015] The ceramic honeycomb structure is covered with glassy carbon, The glassy carbon coating is preferably formed by impregnating a ceramic honeycomb structure with a glassy carbon precursor resin and firing it in a non-oxidizing atmosphere. The invention's effect

 [0016] According to the hot air heater according to the present invention, an electromagnetic current can be attenuated by a reverse current flowing through adjacent heating wires.

[0017] In addition, infrared radiation efficiency can be increased by attaching a ceramic honeycomb structure to the hot air downstream side of the heating wire.

 Brief Description of Drawings

 FIG. 1 is an exploded view showing a first embodiment of a hot air heater according to the present invention.

 FIG. 2 is a conceptual diagram for explaining a heating wire winding mode according to the first embodiment.

 FIG. 3 is a conceptual diagram for explaining a heating wire winding mode of the second embodiment.

 FIG. 4 is a partially broken perspective view for explaining a winding mode of a heating wire of a third embodiment.

 FIG. 5 is a conceptual diagram showing a modification of the third embodiment.

 FIG. 6 is a conceptual diagram for explaining a heating mode of a heating wire according to a fourth embodiment.

 Explanation of symbols

[0019] 1 Hot air heater

 2 Insulated fireproof support

 3a 1st heating wire

 3b Second heating wire

 6 input lines

 7 Output line

 9 Ceramic honeycomb structure

 BEST MODE FOR CARRYING OUT THE INVENTION

[0020] An embodiment of a hot air heater according to the present invention will be described below with reference to Figs. In the following embodiment, an example of a hair dryer is described, and the same components are denoted by the same reference numerals throughout the drawings.

First, the first embodiment of the hot air heater according to the present invention will be described. As shown in FIG. 1, the heating wire 3 is wound around the insulating refractory support 2 as shown in FIG. The heating wire 3 is wound so as to form a spiral along the direction in which the hot air flows by the hot air heater 1 or in the opposite direction.

 [0022] The insulating fireproof support 2 can be formed by a force plate, a ceramic plate or the like, and the illustrated example is formed by crossing plate-like bodies in a cross shape. The heating wire 3 can be formed of a coiled nichrome wire or the like. In FIG. 1, reference numeral 4 is a fan motor, and reference numeral 5 is a fan.

 [0023] As shown conceptually in Fig. 2, the heating wire 3 has two first heating wire 3a and second heating wire 3b connected in parallel between the input line 6 and the output line 7 of the power supply line. is doing. For convenience of illustration and explanation, the heating wire is shown not by a coil but by a simple line.

 [0024] The first heating wire 3a is wound on the input line 6 side from the rear end side to the front end side of the insulating refractory support 2, and is connected to the output line 7 on the front end side of the insulating refractory support. .

 [0025] On the other hand, the second heating wire 3b is connected to the input line at the front end side of the insulated refractory support, wound from the front end side toward the rear end side, and the rear end side of the insulated refractory support 2 Is connected to output line 7.

 [0026] The first heating wire 3a and the second heating wire 3b are wound at a desired interval so as to be alternately arranged, and the heating directions of both the heating wires 3a and 3b are the same direction. . Further, as shown in FIG. 1, the adjacent first heating wire 3a and second heating wire 3b are wound around the insulating refractory support 2 with the same diameter.

 [0027] In the first heating wire 3a and the second heating wire 3b as described above, currents flowing in adjacent heating wires are opposite to each other. The power source of the hot air heater is generally an AC power source, but in that case, the current flowing in the adjacent heating wire is in reverse phase, and the current flowing in a certain time is reversed.

 [0028] When the currents flowing through the adjacent first heating wire 3a and second heating wire 3b are reversed, the magnetic force lines and the electric force lines are offset. This phenomenon occurs due to the phase inversion of the electric and magnetic fields in an AC power supply.

Next, a second embodiment of the hot air heater according to the present invention will be described based on the conceptual diagram shown in FIG. [0030] The second embodiment is similar to the first embodiment in that it includes a first heating wire 3a and a second heating wire 3b connected in parallel between the input line 6 and the output line 7. It is.

 [0031] In the second embodiment, each of the first heating wire 3a and the second heating wire 3b is wound around an insulating refractory support (not shown), and among the wound first heating wires 3a, The second heating wire is wound around the circumference. The first heating wire 3a and the second heating wire 3b are wound in the opposite winding directions. The first heating wire 3a and the second heating wire 3b are wound in parallel along the hot air blowing direction and are concentric when viewed from the front.

 [0032] The first heating wire 3a and the second heating wire 3b are wound around the respective insulating refractory supports (not shown) at equal intervals, and are preferably separated as close as possible. Is wound around.

 [0033] In the second embodiment, the first heating wire 3a and the second heating wire 3b are connected to the input line 6 (or the output line 7) on either the front end side or the rear end side of an insulating refractory support (not shown). It can be connected.

 [0034] Also in the second embodiment having the above-described configuration, the currents flowing through the first heating wire 3a and the second heating wire 3b are opposite to each other and can attenuate electromagnetic waves.

 [0035] It should be understood by those skilled in the art that in the second embodiment, the heating wire can include an even number of heating wires with a force of four or more as described for the two modes. Let's go. Also, the number of heating wires can be an odd number of 3 or more. In this case, the electromagnetic wave generated from each heating wire can be canceled as a whole by adding a resistance to a predetermined heating wire to limit the current value. Can be configured to.

 FIG. 4 is a partially broken perspective view showing the third embodiment. In the embodiment shown in FIG. 3, one heating wire 3 is connected in series between the input line 6 and the output line 7. The heating wire 3 is wound in a concentric cylindrical shape, and the heating wire 3 wound around the inner insulating refractory support 2a is folded back at its end and is placed on the outer insulating refractory support 2b. It is wound in the reverse direction.

[0037] As shown in the conceptual diagram of FIG. 5, the inner heating wire 3 and the outer heating wire 3 can be wound in a crossing manner as a parallel connection via an insulating refractory support 2b as an insulating layer. Therefore, in the present invention, when the current is in the reverse direction, it is not always necessary that all the direction components are in the reverse direction. If it has a direction component in the opposite direction, it will be good. For example, in FIG. 5, the direction component (3ax, 3 ay) of the current flowing through the inner heating wire 3a and the direction component (3bx, 3by) of the current flowing through the outer heating wire 3b are By providing reverse direction components 3ay and 3by, an electromagnetic wave attenuation effect can be obtained.

 FIG. 6 is a conceptual diagram showing the fourth embodiment. In the fourth embodiment, the heating wire 3a wound in the first winding direction and the heating wire 3b wound in the second winding direction opposite to the first winding direction are insulated from heat resistance. It is supported next to the support 2. In the illustrated example, the heating wire 3a and the heating wire 3b are composed of a single heating wire and are connected in series between the input line 6 and the output line 7, and the heating wire 3a and the heating wire 3b are connected to each other. The direction of whispering is changing. Although not shown, the heating wire 3a and the heating wire 3b may be connected in parallel.

 [0039] Further, in the hot air dryer according to the present invention, as shown in Fig. 1, a cylindrical honeycomb structure 9 made of ceramics can be incorporated in a casing 10. The ceramic honeycomb structure 9 is arranged on the downstream side of the hot air of the heating wire 3, and a plurality of hexagonal columnar holes are formed along the blowing direction.

 [0040] Ceramic honeycomb structure 9 is made of SiC, SiO, B C, A1N, Al 2 O 3, MgO, etc.

 2 4 2 3

 The force that can be formed by a known ceramic material, and the cordite is preferable from the viewpoint of manufacturing cost.

 [0041] In general, it is known that radiant energy proportional to the fourth power of absolute temperature is generated from a heated material. In this case, the radiant energy varies depending on the surface state. The higher the emissivity, the larger the radiant energy, but since the ideal black body with the highest emissivity is 1, the closer the emissivity of the heating element is to 1, the greater the radiant energy.

 The ceramic honeycomb structure 9 formed of the above material generally has an infrared emissivity of 0.8 to 0.98. Depending on the wavelength of infrared rays, an infrared of 0.7 or less is used. Sometimes the line emissivity.

[0043] Carbon powder has a high emissivity over the entire wavelength region. Therefore, it is preferable to set the emissivity in the entire infrared wavelength region to 0.8 or more by applying a coating containing carbon powder to the ceramic honeycomb structure 9. Is more preferred [0044] The coating containing carbon powder is obtained by mixing and dispersing carbon powder in a resin binder, and impregnating the honeycomb structure 9 made of ceramics by spraying, brushing, or the like, or dating. Thereafter, it can be obtained by drying. The carbon powder may be crystalline such as graphite or amorphous such as glassy carbon. The coating can also be applied only to one side surface of the ceramic honeycomb structure 9, for example, the blown side surface.

 [0045] Specifically, the coating is, for example, a normal temperature curable inorganic-organic hybrid binder (for example, phosphate and polyhydroxybenzene binder, manufactured by Techec Co., Ltd.) with 100 parts by weight of carbon particles 5 to A mixture obtained by stirring and mixing 30 parts by weight can be formed by coating or dipping and then air drying.

 The particle diameter of the carbon powder is preferably about 1 to 50 / im, but more preferably about 1 to 30 μΐη, and most preferably about 1 to 5 / im. This is because the finer the particles, the more uniformly the ceramic surface can be applied or impregnated.

 [0047] There is also a method of improving the infrared radiation efficiency without including carbon powder in the coating. One method is to impregnate a ceramic honeycomb structure with a glassy carbon precursor resin for the required time, and then firing it at a specified temperature (approximately 800 to 2000 ° C) in a non-oxidizing atmosphere. A glassy carbon coating can be formed. The thickness of the glassy carbon coating can be 5 to: 100 x m.

[0048] The glassy carbon coating significantly improves the infrared radiation efficiency due to the carbonization treatment, and an average emissivity of 0.95 or more is obtained in the entire infrared wavelength region. For example, the radiant divergence is 1.227 kW / m ² at ε = 0.95 when the air blower blower at 20 ° C is used (all infrared region with a wavelength of 0.7 μm or more, ε = 1 black The body is 1.292kWZm ² ).

 [0049] The ceramic honeycomb structure 9 is preferably porous from the viewpoint of impregnation. The pore diameter is preferably about:! To 50 x m. This is because if the porous pore size is smaller than 1 μm, carbon powder may cause lumps, and if it is larger than 50 μm, the coating may be inhomogeneous.

[0050] The ceramic honeycomb structure 9 is preferably disposed in the vicinity of the heating wire 3 from the viewpoint of the force infrared radiation efficiency arranged on the downstream side of the hot air of the heating wire 3, for example, the heating wire 3 When Is preferably about 0 to 2 cm. Depending on the arrangement state of the heating wire 3 wound in a cylindrical shape, for example, the ceramic honeycomb structure 9 may be placed in the cylindrical space formed by the wound heating wire 3. It is also possible to arrange. Example

 [0051] A hot-air dryer (Example 1) having the heating wire arrangement form shown in Fig. 6 and a conventional commercially available hot-air dryer in which all the heating wires are run in the same direction and all current flows in the same direction Table 1 shows the measurement results of electromagnetic waves for (Comparative Example 1).

[0052] The test conditions are as follows.

[0053] Heating wire: 0.3mm φ, Nichrome wire

 Power consumption: 1200W

 Power supply: AC 100V, 60Hz

 Measuring instrument:

 Electric field: ME3 electromagnetic wave measuring instrument manufactured by Marl Burda Technique (Germany)

 Magnetic field: EMS tester manufactured by TES Electrical Electronic Corp. TES1390 Measurement position: (A) to (C) below

 (A) Hot air blowing loca about 5cm in the blowing direction

 (B) About 5cm from the casing surface where the heating wire is built

 (C) Casing surface force at the position where the fan motor is built-in Approx. 5 cm

 Position of

 [0054] [Table 1]

[0055] From the results in Table 1, it can be seen that in Example 1, the magnetic field and the electric field are greatly reduced at the measurement position A. It is important that the electromagnetic wave at the measurement position A is attenuated because the hot air outlet is the shortest distance from the human body like a hair dryer. In the measurement shown in Table 1, the electric field is almost lost by grounding the hot air heater tested without grounding.

 [0056] Next, the ceramic honeycomb structure was subjected to an infrared emissivity comparison test with and without carbon powder coating.

 [0057] Example A of honeycomb structure made of ceramics

 Resonol type phenolic resin methanol solution (resin content 50wt%) 10g of lg black ship powder (average particle size 12 / zm) was mixed with this, and a ceramic honeycomb structure with a diameter of 3cm made of cordierite was mixed therewith. The infrared emissivity of the impregnated coating and drying was 0.96.

 [0058] Example B of Ceramic Honeycomb Structure

 A glassy carbon precursor resin prepared by adjusting a solution of a resol type phenolic resin in methanol to a resin solid content of 30 wt% was manufactured, and the glassy carbon precursor resin was formed into a mullite honeycomb structure. After impregnation and drying, it was cured at 150 ° C. This was fired in nitrogen gas from room temperature to 1000 ° C. for 12 hours, and then cooled to room temperature over 8 hours, whereby a glassy carbon coating was applied to the honeycomb structure made of mullite. The mullite honeycomb structure covered with glassy carbon had an infrared radiation efficiency of 0.95.

 [0059] Example C of a ceramic honeycomb structure

 Resorcinol lmol, terephthalaldehyde 1.5mol, and curing accelerator (p-toluenesulfonic acid) 0. Olmol was dissolved in ethanol to produce a glassy carbon precursor resin adjusted to a resin solid content of 30wt%. A mullite honeycomb structure was impregnated with a carbon-like carbon precursor resin and dried, followed by curing at room temperature for 5 hours. This was fired in nitrogen gas from room temperature to 1000 ° C. for 12 hours, and then cooled to room temperature over 8 hours, whereby a glassy carbon coating was applied to the honeycomb structure made of mullite. The mullite honeycomb structure covered with glassy carbon had an infrared radiation efficiency of 0.95.

[0060] On the other hand, as a comparative example of the ceramic honeycomb structure, an infrared emissivity was 0.87 to 0.89 in the ceramic honeycomb structure without any coating. In addition, a radiation thermometer IT-1 540N manufactured by HORIBA, Ltd. was used for the measurement of infrared emissivity. Using this radiation thermometer, the emissivity was measured as follows. First, (1) A black body spray is applied to a part of the object to be measured, and then the object to be measured is heated. Next, (2) Measure the area where the black body spray is applied with a radiation thermometer using the emissivity value of the black body spray as the emissivity setting value. Next, (3) Measure the part where the black body spray is not applied, and adjust the emissivity setting value so that the temperature of the part where the black body spray is measured and the indicated value are equal. (4) The emissivity obtained by the adjustment was defined as the emissivity of this measured object.

Claims

The scope of the claims  [1] A hot air heater in which a heating wire is wound on an insulating refractory support,  A heating wire connected in series or in parallel between the input line and the output line of the power supply line so that the current flowing through the heating wire is reversed so as to cancel out electromagnetic waves generated from the heating wire. A warm wind turbine heater wound around the insulating refractory support.  [2] A first heating wire and a second heating wire are connected in parallel between the input line and the output line of the power supply line, and the first heating wire and the second heating wire transmit electromagnetic waves generated from the heating wire. The first heating wire and the second heating wire adjacent to each other in the same direction and in the same direction around the insulating refractory support so that the currents flowing through the first heating wire and the second heating wire are in opposite directions so as to cancel each other. 2. The hot air heater according to claim 1, wherein the two heating wires are wound with the same diameter and wound.  [3] The hot air heater according to claim 1 or 2, wherein a ceramic honeycomb structure is provided on the downstream side of the hot air of the heating wire.  [4] The ceramic honeycomb structure is coated with carbon powder, and the ceramic honeycomb structure with the coating has an emissivity of 0.8 or more in the entire infrared wavelength region. The hot air heater according to claim 3, wherein:  [5] The hot air heater according to [4], wherein an emissivity in a total infrared wavelength region of the ceramic honeycomb structure having the coating is 0.9 or more.  6. The warm air heater according to claim 4, wherein the coating containing the carbon powder is an impregnation coating.  7. The hot air heater according to claim 3, wherein the ceramic honeycomb structure is disposed in the vicinity of the heating wire. [8] The ceramic honeycomb structure is coated with glassy carbon, and the glassy carbon coating is non-oxidized after the ceramic honeycomb structure is impregnated with the glassy carbon precursor resin. The hot air heater according to claim 3, wherein the hot air heater is formed by firing in an atmosphere.