Air heater

Abstract

Air heater (200) comprising: a direct heat generating section (270) configured to be heated by externally supplied electric power; an indirect heat generating section configured to be heated by conductive heat supplied by physical contact with the heated direct heat generating section (270), and configured to heat air flowing in through an inlet opening (231, 251) formed on one side while the air flows out through an outlet opening (235) formed on the other side; and a housing (210) made of an insulating material providing a space in which the direct heat generating section (270) and the indirect heat generating section are placed, and comprising an air inlet (211) on one side through which the air is sucked in from outside and an air outlet (215) on the other side through which the air is discharged, wherein the indirect heat generating section comprises a first indirect heat generating section (230) and a second indirect heat generating section (250), wherein the direct heat generating section (270) is embedded between the first indirect heat generating section (230) and the second indirect heat generating section (250), wherein air passing through the air inlet (211) is divided into a first air portion flowing through the interior of the first indirect heat generating section (230) and a second air portion flowing through the space between the housing (210) and the second indirect heat generating section (250), wherein the first indirect heat generating section (230) heats the first air portion, and at the same time the second indirect heat generating section (250) heats the second air portion, wherein the direct heat generating section (270) comprises a zigzag-shaped electric heating wire.

Description

BACKGROUND OF THE INVENTIONField of the InventionThe present disclosure relates to an air heater, and more particularly, to an air heater that does not cause contaminants.Prior ArtAir heaters that heat a heating object by blowing hot air are used in various fields. Conventional air heaters heat the air by passing air through a glass tube into which a spirally wound heating wire is inserted.As shown in FIG. 1, a prior Unexamined Utility Model No. 20-2012-0002039 discloses an air heater which has a quartz glass tube 140 for insulation inserted into the surface of a stainless housing box 130, and which, when air is sucked into an air inlet opening 131, heats the air as it passes through a rectangular spiral heating wire 120 fixed to a spiral high-temperature coil 110.However, heating wires such as nichrome wires used for heating may have particles which break off due to the nature of the metal and are mixed with the air. Therefore, in conventional air heaters, problems such as reduction in yield due to the inclusion of impurities occur when they are applied to semiconductors, LEDs, etc. requiring high purity. Patent Document 2 teaches a tubular heating element for heating fluid, which is composed of an inner tube and an outer tube, and a planar heating element interposed therebetween. Further, from Patent Document 3, a heat generating device is known which is composed of a centrally disposed elongated first heater made of carbon fiber, which is enclosed by a tubular quartz glass, and a second heater disposed further outward, which is also enclosed by a tubular quartz glass, and is heated by the first heater.Therefore, there is a need in this technical field for air heaters that do not cause impurities.[Prior Art Documents][Patent Documents]Patent Document 1: KR 20 2012 0 002 039 UPatent Document 2: JP H11-144 849 APatent Document 3: JP 2000-311 768 ASUMMARY OF THE INVENTIONThe present disclosure provides an air heater that enables no contaminants to enter a heating object and that can heat the air efficiently.According to one aspect of the present disclosure, an air heater is provided. The air heater includes: a direct heat generation portion configured to be heated by electric power supplied from the outside; an indirect heat generation portion configured to be heated by conductive heat supplied by physical contact with the heated direct heat generation portion and configured to heat air flowing in through an inlet opening formed on one side while the air flows through an outlet opening formed on the other side; and a housing made of an insulating material that provides a space in which the direct heat generation portion and the indirect heat generation portion are placed and that includes an air inlet on one side through which the air is sucked from the outside and an air outlet on the other side through which the air is discharged, wherein the indirect heat generation portion includes a first indirect heat generation portion and a second indirect heat generation portion, the direct heat generation portion being sandwiched between the first indirect heat generation portion and the second indirect heat generation portion, air passing through the air inlet being divided into a first air portion passing through the inside of the first indirect heat generation portion and a second air portion passing through the space between the housing and the second indirect heat generation portion, the first indirect heat generation portion heating the first air portion, and at the same time the second indirect heat generation portion heating the second air portion, the direct heat generation portion including a zigzag shaped electric heating wire.According to another aspect of the present disclosure, the air heater may further include a frame that forms a support between the housing and the indirect heat generation portion so that the housing and the indirect heat generation portion are fixed at a certain distance from each other.According to another aspect of the present disclosure, the air heater may further include a lead portion that supplies electric power to the direct heat generation portion.According to another aspect of the present disclosure, the housing may be made of quartz.According to another aspect of the present disclosure, the indirect heat generation portion may be made of a nonmetallic material.According to another aspect of the present disclosure, the indirect heat generation portion may be made of ceramic.According to another aspect of the present disclosure, the direct heat generation portion may be made of either nichrome or tungsten.According to another aspect of the present disclosure, the housing and the indirect heat generation portion may have a cylindrical structure.According to the present disclosure, there is provided an air heater that allows no contaminants to enter a heating object because it does not cause particles.BRIEF DESCRIPTION OF THE DRAWINGSFig. 1 shows an example of an air heater structure according to the prior art. FIG. 2 is a plan view of an air heater according to an exemplary embodiment of the present disclosure. FIG. 3 illustrates a cross-sectional view of the air heater of FIG. 2 according to the exemplary embodiment of the present disclosure. FIG. 4 shows a pattern structure of a direct heat generation portion according to an exemplary embodiment of the present disclosure. FIG. 5 shows a top view of a further air heater. FIG. 6 is a cross-sectional view of the air heater of FIG. 5. FIG. 7 shows a top view of a further air heater. FIG. 8 illustrates a cross-sectional view of the air heater of FIG. 7.DESCRIPTION OF EXEMPLARY EMBODIMENTSHereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings, so that those skilled in the art can easily carry out the present disclosure. However, the present disclosure may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Also, in order to clearly illustrate the present disclosure in the drawings, parts that do not relate to the present disclosure are omitted, and the same or similar reference numerals denote the same or similar constituent elements.The objects and effects of the present disclosure can be naturally understood or will become apparent from the following description, and the objects and effects of the present disclosure are not limited only by the following description.The objects, features and advantages of the present disclosure will become more apparent from the following detailed description. When it is determined in describing the present disclosure that the detailed description of the known technology related to the present disclosure may unnecessarily obscure the gist of the present disclosure, the detailed description thereof will be omitted.FIGS. 2 and 3 show an air heater 200 according to an exemplary embodiment of the present invention. FIG. 2 is a plan view of the air heater 200, and FIG. 3 is a cross-sectional view of the air heater 200.Referring to FIGS. 2 and 3, the air heater 200 includes a housing 210, a first indirect heat generation portion 230, a second indirect heat generation portion 250, a direct heat generation portion 270, a frame 290, and a duct portion 295.The housing 210 provides a space therein in which the first and second indirect heat generation portions 230 and 250 and the direct heat generation portion 270 may be placed, having an air inlet 211 on one side through which air is sucked from outside and an air outlet 215 on the other side through which the air is discharged. The housing 210 may be made of an insulating material, for example, a quartz material that does not deform under heat and has an insulating effect. Although the housing 210 is formed cylindrically in FIGS. 2 and 3, it may be formed in various shapes such as a triangular prism, a rectangular prism, etc. Meanwhile, heated air is discharged to a heating object via the housing 210, and the housing 210 is preferably formed longer than the first and second indirect heat generation portions 230 and 250.The first and second indirect heat generation portions 230 and 250 may be placed inside the housing 210 and may be formed in a shape of a hollow rod. First and second air inlet ports 231 and 251 are formed on one side of the first and second indirect heat generation portions 230 and 250 to suck air from the outside. The first and second air inlet ports 231 and 251 are positioned at the same locations as the first and second indirect heat generation portions 230 and 250. Meanwhile, an exhaust port 235 for exhausting air sucked through the first and second air inlet ports 231 and 251 is formed on the other side of the first indirect heat generation portion 230. The first and second indirect heat generation portions 230 and 250 may be in various shapes, such as a triangular prism, rectangular prism, cylinder, etc. Moreover, the first and second indirect heat generation portions 230 and 250 may be made of a nonmetallic material, preferably a nonmetallic material that does not deform at high temperatures and has high thermal conductivity. In one example, a ceramic material obtained by firing at a high temperature of 1600° C. may be used. The direct heat generation portion 270 is configured as an electric heating wire or an electric heating pattern capable of generating heat by application of electricity. In an example, the direct heat generation portion 270 may be made of a metal material such as nichrome wire, tungsten, etc. Meanwhile, the direct heat generation portion 270 may be in a plurality of shapes, for example, in the form of an electric heating pattern shown in FIG. 4. The direct heat generation portion 270 is placed so as to surround the outside of the first indirect heat generation portion 230, and then the outer ceramic portion 250 is placed so as to surround the outside of the direct heat generation portion 270. Thus, the direct heat generation portion 270 is sandwiched between the first indirect heat generation portion 230 and the second indirect heat generation portion 250. The frame 290 serves as a support so that the housing 210 and the second indirect heat generation portion 250 are fixed at a certain distance from each other, and the lead portion 295 electrically connects a power source and the direct heat generation portion 270 to each other to supply electric power to the direct heat generation portion 270.According to an example of the present disclosure, air may enter the inside of the first indirect heat generation portion 230 from one end and be discharged at the other end. At this point, the air is heated to a high temperature when it comes into contact with the inside of the first indirect heat generation portion 230. Since the air is heated by the first indirect heat generation portion 230 without coming into contact with the direct heat generation portion 270, contaminants that can be generated from high temperature metals cannot enter the air. At this point, the first indirect heat generation portion 230 may be made thinner than the second indirect heat generation portion 250 to further improve the thermal efficiency.In another example, air may enter from one end of a space formed between the second indirect heat generation portion 250 and the housing 210 and be discharged at the other end. At this point, the air is heated to a high temperature when it comes into contact with the outside of the second indirect heat generation portion 250. Also in this case, the air comes into contact with only the second indirect heat generation portion 250 and the housing 210, but not the direct heat generation portion 270, thereby preventing contaminants that may be generated by high-temperature metals from entering the air. At this point, the second indirect heat generation portion 250 may be made thinner than the first indirect heat generation portion 230 to further improve the thermal efficiency.In yet another example, air may flow through both a space formed inside the first indirect heat generation portion 230 and the space formed between the second indirect heat generation portion 250 and the housing 210. At this point, the air is heated by the inside of the first indirect heat generation portion 230 and the outside of the second indirect heat generation portion 250, thereby further improving the thermal efficiency as compared with the foregoing examples.While in this exemplary embodiment, the frame 290 is formed only in a part of the space between the housing 210 and the second indirect heat generation portion 250 and serves only to form a support between the housing 210 and the second indirect heat generation portion 250, it may also be formed to block the entire space between the housing 210 and the second indirect heat generation portion 250 and serve as a stopper for preventing air movement between the housing 210 and the second indirect heat generation portion 250.The speed at which the air is heated is determined by the amount of electric power supplied to the direct heat generation portion 270, the contact area between the air and the first indirect heat generation portion 230 and / or the second indirect heat generation portion 250, and the speed at which the air flows through the first indirect heat generation portion 230 and / or the second indirect heat generation portion 250. Specifically, the temperature of the air can therefore be adjusted as necessary by the above-mentioned parameters.FIGS. 5 and 6 show another air heater 500. FIG. 5 illustrates a plan view of the air heater 500, and FIG. 6 illustrates a cross-sectional view of the air heater 500.Referring to FIGS. 5 and 6, the air heater 500 includes a housing 510, an indirect heat generation portion 530, a direct heat generation portion 570, a frame 590, and a duct portion 595.The housing 510 provides a space therein in which the indirect heat generation portion 530 and the direct heat generation portion 570 may be placed, having an air inlet 511 on one side through which air is sucked from the outside and an air outlet 515 on the other side through which the air is discharged. The housing 510 may be made of an insulating material, for example, a quartz material that does not deform under heat and has an insulating effect. Although the housing 510 is formed cylindrically in FIGS. 5 and 6, it may be formed in various shapes such as a triangular prism, a rectangular prism, etc. Meanwhile, heated air is discharged to a heating object via the housing 510, and the housing 510 is preferably formed longer than the indirect heat generation portion 530.The indirect heat generation portion 530 may be placed inside the housing 510 and may be formed in a shape of a hollow rod. An air inlet port 531 is formed at a side of the indirect heat generation portion 530 to suck air from the outside. Meanwhile, an exhaust port 535 for discharging air sucked through the air inlet port 531 is formed on the other side of the indirect heat generation portion 530. The indirect heat generation portion 530 may be in various shapes, such as a triangular prism, rectangular prism, cylinder, etc. Moreover, the indirect heat generation portion 530 may be made of a non-metallic material, preferably a non-metallic material that does not deform at high temperatures and has high thermal conductivity. For example, a ceramic material obtained by firing at a high temperature of 1600° C. may be used. The direct heat generation portion 570 is disposed so as to surround the outside of the indirect heat generation portion 530, and is configured as an electric heating wire or an electric heating pattern capable of generating heat by application of electricity. In an example, the direct heat generation portion 570 may be made of a metal material such as Nich chrome wire, tungsten, etc. Meanwhile, the direct heat generation portion 570 may be in a variety of forms, for example, in the form of an electric heating pattern shown in FIG. 4. The direct heat generation portion 570 is placed so as to surround the outside of the indirect heat generation portion 530. The frame 590 serves as a support so that the housing 510 and the indirect heat generation portion 530 are fixed at a certain distance from each other, and the lead portion 595 electrically connects a power supply source and the direct heat generation portion 570 to supply electric power to the direct heat generation portion 570.In this variation, air may enter a space formed by the indirect heat generation portion 530 from one end to minimize friction between the air and the direct heat generation portion 570. At this point, the air is heated to a high temperature when it comes into contact with the inner surface of the indirect heat generation portion 530. The air is heated as it flows through the inside of the indirect heat generation portion 530 without friction with the direct heat generation portion 570, and this can minimize contaminants that are generated by high temperature metals and can enter the air. Meanwhile, although not illustrated in the drawings, a seal portion may be further included at an end of the housing 510 to prevent air from passing between the housing 510 and the indirect heat generation portion 530. Moreover, the frame 590 may serve as a sealing portion to stop an air flow between the housing 510 and the indirect heat generation portion 530.FIGS. 7 and 8 show another air heater 700. FIG. 7 illustrates a top view of the air heater 700, and FIG. 8 illustrates a cross-sectional view of the air heater 700.Referring to FIGS. 7 and 8, the air heater 700 includes a housing 710, an indirect heat generation portion 730, a direct heat generation portion 770, a frame 790 and a duct portion 795.

[50] The housing 710 provides a space therein in which the indirect heat generation portion 730 and the direct heat generation portion 770 may be placed, having an air inlet 711 on one side through which air is sucked from the outside and an air outlet 715 on the other side through which the air is discharged. The housing 710 may be made of an insulating material, for example, a quartz material that does not deform under heat and has an insulating effect. Although the housing 710 is formed cylindrically in FIGS. 7 and 8, it may be formed in various shapes such as a triangular prism, a rectangular prism, etc. Meanwhile, heated air is discharged to a heating object via the housing 710, and the housing 710 is preferably formed longer than the indirect heat generation portion 730.The indirect heat generation portion 730 may be placed inside the housing 710 and may be formed in a shape of a hollow rod. An air inlet port 731 is formed on a side of the indirect heat generation portion 730 to suck air from the outside. Meanwhile, an exhaust port 735 for discharging air sucked through the air inlet port 731 is formed on the other side of the indirect heat generation portion 730. The indirect heat generation portion 730 may be in various shapes, such as a triangular prism, a rectangular prism, a cylinder, etc. Moreover, the indirect heat generation portion 730 may be made of a nonmetallic material, preferably a nonmetallic material that does not deform at high temperatures and has high thermal conductivity. In one example, a ceramic material obtained by firing at a high temperature of 1600° C. may be used. The direct heat generation portion 770 is placed on an inner wall surface of the indirect heat generation portion 730, and is configured as an electric heating wire or electric heating pattern capable of generating heat by application of electricity. In an example, the direct heat generation portion 770 may be made of a metal material such as nichrome wire, tungsten, etc. Meanwhile, the direct heat generation portion 770 may be in various shapes, for example, in the shape of an electric heating pattern shown in FIG. 4. The frame 790 serves as a support so that the housing 710 and the indirect heat generation portion 730 are fixed at a certain distance from each other, and the lead portion 795 electrically connects a power supply source and the direct heat generation portion 770 to supply electric power to the direct heat generation portion 770.In this exemplary embodiment, air may enter from an end of a space formed between the housing 710 and the indirect heat generation portion 730 to minimize friction between the air and the direct heat generation portion 770. At this point, the air is heated to a high temperature when it comes into contact with the outer surface of the indirect heat generation portion 730. The air is heated as it flows through the space between the housing 710 and the indirect heat generation portion 730 without friction with the direct heat generation portion 770, and this can minimize contaminants that are generated by high temperature metals and that can enter the air. Meanwhile, although not shown in the drawings, a seal portion may be further included at an end of the indirect heat generation portion 730 to prevent air from entering the inside of the indirect heat generation portion 730.While conventional air heaters have a problem that fine metal particles or the like can enter the air from a heating wire because the air is heated by direct contact with the heating wire, the present disclosure enables heating of the air without metal particles entering the air because the heating wire is embedded between ceramic portions and the air is heated not directly by the heating wire but indirectly by the ceramic portions.

Claims

An air heater (200) comprising: a direct heat generation portion (270) configured to be heated by electric power supplied from the outside; an indirect heat generation portion configured to be heated by conductive heat supplied by physical contact with the heated direct heat generation portion (270) and configured to heat air flowing in through an inlet opening (231, 251) formed on one side while the air flows through an outlet opening (235) formed on the other side; and a housing (210) made of an insulating material that provides a space in which the direct heat generation portion (270) and the indirect heat generation portion are placed and that includes an air inlet (211) on one side through which the air is sucked from the outside and an air outlet (215) on the other side, through which the air is discharged, wherein the indirect heat generation section has a first indirect heat generation section (230) and a second indirect heat generation section (250), wherein the direct heat generation section (270) is embedded between the first indirect heat generation section (230) and the second indirect heat generation section (250), wherein air which passes through the air inlet (211) is divided into a first air portion which flows through the interior of the first indirect heat generation section (230) and into a second air portion which flows through the space between the housing (210) and the second indirect heat generation section (250), wherein the first indirect heat generation section (230) heats the first air portion, and wherein at the same time the second indirect heat generation section (250) heats the second air portion, wherein the direct heat generating portion (270) comprises a zigzag shaped electric heating wire.The air heater (200) according to claim 1, further comprising a frame (290) that forms a support between the housing (210) and the indirect heat generation portion so that the housing (210) and the indirect heat generation portion are fixed at a certain distance from each other.The air heater (200) according to claim 1, comprising a lead portion (295) that supplies electric power to the direct heat generation portion (270).The air heater (200) of claim 1, wherein the housing (210) is made of quartz.The air heater (200) of claim 1, wherein the indirect heat generation portion is made of a nonmetallic material.The air heater (200) according to claim 5, wherein the indirect heat generation portion is made of ceramic.The air heater (200) of claim 1, wherein the direct heat generation portion (270) is made of either nichrome or tungsten.The air heater (200) according to claim 1, wherein the housing (210) and the indirect heat generation portion have a cylindrical structure.

Images