TWM615787U - Tubular heater - Google Patents

Abstract

The present invention provides a tubular heater, which includes a tubular substrate, a heating layer and at least two electrodes. The heating layer includes a strip-shaped carbon nanotube layer, and the at least two electrodes are located on the strip-shaped carbon nanotubes. The surface of the tube layer, wherein the carbon nanotube layer is spirally wound on the surface of the tubular substrate to form the heating layer, and the at least two electrodes are respectively disposed on both ends of the strip-shaped carbon nanotube layer. The strip-shaped carbon nanotube layer includes a plurality of mutually parallel carbon nanotubes, and the extending direction of the plurality of carbon nanotubes is the same as the extending direction of the strip-shaped carbon nanotube layer.

Description

Tubular heater

The model relates to a heater, in particular to a tubular heater.

The heaters in the prior art generally use metal wires as heating elements, such as chromium-nickel alloy wires, copper wires, molybdenum wires, or tungsten wires, which are formed by laying or winding. However, the use of metal wire as a heating element has the following shortcomings: First, the surface of the metal wire is easily oxidized, resulting in increased local resistance and burned out, so the service life is short; second, the metal wire is gray body radiation, so heat The radiation efficiency is low, the radiation distance is short, and the radiation is uneven; third, the density of the metal wire is large, the weight is large, and it is inconvenient to use.

In order to solve the problems of metal wire as a heating element, carbon fiber has become a hot spot in the research of heating element materials because of its good black body radiation performance and low density. When carbon fiber is used as a heating element, it usually exists in the form of carbon fiber paper. The carbon fiber paper includes a paper base material and pitch-based carbon fibers randomly distributed in the paper base material. Among them, the paper substrate includes a mixture of cellulose fiber and resin, etc. The pitch-based carbon fiber has a diameter of 3-6 mm and a length of 5-20 microns. However, the use of carbon fiber paper as a heating element has the following disadvantages: First, because the pitch-based carbon fibers in the carbon fiber paper are randomly distributed, the carbon fiber paper has low strength, poor flexibility, and is easy to break, and it also has the shortcomings of short life; Second, carbon fiber paper has low electrothermal conversion efficiency, which is not conducive to energy conservation and environmental protection.

In view of this, it is indeed necessary to provide a tubular heater that can solve the above technical problems.

A tubular heater includes a tubular substrate, a heating layer, and at least two electrodes. The heating layer includes a strip-shaped carbon nanotube layer, and the at least two electrodes are located on the strip-shaped carbon nanotube layer The surface of the carbon nanotube layer, wherein the carbon nanotube layer is spirally wound on the surface of the tubular substrate to form the heating layer, and the at least two electrodes are respectively disposed on both ends of the strip-shaped carbon nanotube layer. The carbon nanotube layer includes a plurality of carbon nanotubes parallel to each other, and the extending direction of the plurality of carbon nanotubes is the same as the extending direction of the strip-shaped carbon nanotube layer.

Compared with the prior art, the described tubular heater has the following advantages: First, because the carbon nanotube layer has better strength and toughness, the carbon nanotube layer has greater strength, and the carbon nanotube layer has good flexibility. , Not easy to break, so that it has a long service life. Second, the carbon nanotubes in the carbon nanotube layer are evenly distributed. The carbon nanotube structure has uniform thickness and resistance, and heats evenly. The carbon nanotubes have high electrothermal conversion efficiency, so the tubular heater has a rapid temperature rise. Features of small thermal lag and fast heat exchange speed.

In the following, the tubular heater provided by the present invention will be further described in detail with reference to the drawings and specific embodiments.

Please refer to FIG. 1, an embodiment of the present invention provides a tubular heater 100, which includes a tubular substrate 102, a strip-shaped carbon nanotube layer 104, a first electrode 106 and a second electrode 108. The strip-shaped carbon nanotube layer 104 is spirally wound on the surface of the tubular substrate 102 to form the heating layer, and the first electrode 106 and the second electrode 108 are respectively disposed on the strip-shaped carbon nanotube Both ends of layer 104. Referring to FIG. 2, the strip-shaped carbon nanotube layer 104 includes a plurality of carbon nanotubes 1042 parallel to each other, and the extending direction of the plurality of carbon nanotubes 1042 and the strip-shaped carbon nanotube layer 104 The extension direction is the same.

The material of the tubular base 102 is an insulating material. The cross section of the tubular base 102 may be circular, triangular, square or other shapes. An object to be heated is arranged inside the tubular base 102, and the object to be heated may be a fixed object or a fluid.

The length and width of the strip-shaped carbon nanotube layer 104 can be selected according to actual needs. The strip-shaped carbon nanotube layer 104 includes at least one layer of carbon nanotube film. The drawn carbon nanotube film is a carbon nanotube film obtained by pulling from a carbon nanotube array. The strip-shaped carbon nanotube layer may include one layer of drawn carbon nanotube film or two or more layers of drawn carbon nanotube film. The drawn carbon nanotube film includes a plurality of carbon nanotubes that are oriented in the same direction and arranged parallel to the surface of the drawn carbon nanotube film. The carbon nanotubes are connected end to end through van der Waals forces. Please refer to FIGS. 3 and 4, each drawn carbon nanotube film includes a plurality of carbon nanotube segments 143 arranged continuously and oriented. The plurality of carbon nanotube segments 143 are connected end to end by van der Waals force. Each carbon nanotube segment 143 includes a plurality of carbon nanotubes 145 parallel to each other, and the plurality of carbon nanotubes 145 parallel to each other are tightly connected by Van der Waals force. The carbon nanotube segment 143 has any width, thickness, uniformity and shape. The thickness of the drawn carbon nanotube film is 0.5 nanometers to 100 microns, and the width is related to the size of the carbon nanotube array from which the drawn carbon nanotube film is drawn, and the length is not limited. For the carbon nanotube stretched film and its preparation method, please refer to Fan Shoushan et al.’s application on February 9, 2007 and published on August 13, 2008. Chinese Published Patent Application No. CN101239712A "Carbon Nanotube Film Structure" And its preparation method", applicant: Tsinghua University, Hongfujin Precision Industry (Shenzhen) Co., Ltd. In order to save space, it is only cited here, but all the technical disclosures of the above-mentioned applications should also be regarded as part of the technical disclosures of the present application.

When the carbon nanotube layer includes two or more layers of carbon nanotube drawn films, the multi-layer carbon nanotube drawn films are arranged on top of each other or arranged side by side. The carbon nanotubes arranged in the preferred orientation in the drawn film of two adjacent carbon nanotubes are parallel to each other. In this embodiment, the strip-shaped carbon nanotube layer 104 is formed by laminating 100 layers of carbon nanotubes.

The first electrode 106 and the second electrode 108 are respectively located at two ends of the strip-shaped carbon nanotube layer 104. The length of the first electrode 106 and/or the second electrode 108 is less than or equal to the width of the strip-shaped carbon nanotube layer 104. The material of the first electrode 108a and the second electrode 108b may be metal, alloy, indium tin oxide (ITO), antimony tin oxide (ATO), conductive silver paste, conductive polymer, conductive carbon nanotube, etc. The metal or alloy material may be aluminum, copper, tungsten, molybdenum, gold, titanium, neodymium, palladium, cesium, or alloys of any combination thereof.

The expanded schematic diagram of the strip-shaped carbon nanotube layer 104 is shown in FIG. 2. The extending direction of the carbon nanotubes 145 is the same as the extending direction of the strip-shaped carbon nanotube layer 104, extending from the first electrode 106 to the second electrode 108. Since the conductive direction of the carbon nanotube 145 is the length direction of the carbon nanotube 145, the conductive direction of the strip-shaped carbon nanotube layer 104 is the length direction of the strip-shaped carbon nanotube layer 104. The width direction of the rice carbon tube layer 104 is almost non-conductive. When the strip-shaped carbon nanotube layer 104 is wound on the tubular substrate 102, a plurality of spiral ring structures 1042 are formed. Two adjacent spiral ring structures 1042 can be arranged at intervals, as shown in FIG. 1. Since the strip-shaped carbon nanotube layer 104 is almost non-conductive in the width direction, two adjacent spiral ring structures 1042 can also be in contact with each other, as shown in FIG. 5. When two adjacent spiral ring structures 1042 are in contact with each other, the heating layer formed by the strip-shaped carbon nanotube layer 104 wraps the entire tubular substrate 102 and has a more uniform heating property.

The strip-shaped carbon nanotube layer 104 is formed by winding the tubular substrate 102 to form a heating layer. The length of the strip-shaped carbon nanotube layer 104 is not limited to be equal to the length of the tubular substrate 102. The length of the layer 104 can be adjusted by adjusting the width of the strip-shaped carbon nanotube layer, the number of windings, and the distance between adjacent spiral ring structures 1042. Therefore, the resistance of the heating layer can be adjusted. The power can be set as required.

Referring to FIGS. 6 and 7, the second embodiment of the present invention provides a tubular heater 200, which includes a tubular substrate 202, a ribbon-shaped carbon nanotube layer 204, a first electrode 206 and a second electrode 208. The strip-shaped carbon nanotube layer 204 includes a first end 2042 and a second end 2044. The strip-shaped carbon nanotube layer 204 is separated from the first end 2042 to form a first part 204a and a second part 204b. The first part 204a and the second part 204b are strip-shaped. The first part 204a and the second part 204b are connected to each other at the second end 2044. The first electrode 206 and the second electrode 208 are located at the first end portion 2042 of the strip-shaped carbon nanotube layer 204, and are electrically connected to the first portion 204a and the second portion 204b, respectively. When a voltage is applied between the first electrode 206 and the second electrode 208, when the voltage of the first electrode 206 is greater than that of the second electrode 208, current flows from the first electrode 206 to the first portion 204a along the length of the first portion 204a It flows from the second end 2044 to the second portion 204b, along the length of the second portion 204b, to the second electrode 208; when the voltage of the first electrode 206 is lower than the second electrode 208, the direction of the current is opposite.

After the strip-shaped carbon nanotube layer 204 is wound on the tubular base 202, the first part 204a and the second part 204b can be formed by cutting.

The above arrangement of the heating layer and the electrode, even when the length of the tubular base 202 of the tubular heater 200 is short, can make the current flow path longer, adjust the resistance of the heating layer, and further adjust the heating power.

Compared with the prior art, the described tubular heater has the following advantages: First, because the carbon nanotube layer has better strength and toughness, the carbon nanotube layer has greater strength, and the carbon nanotube layer has good flexibility. , Not easy to break, so that it has a long service life. Second, the carbon nanotubes in the carbon nanotube layer are evenly distributed. The carbon nanotube structure has uniform thickness and resistance, and heats evenly. The carbon nanotubes have high electrothermal conversion efficiency, so the tubular heater has a rapid temperature rise. Features of small thermal lag and fast heat exchange speed.

In summary, this new model does meet the requirements of a new patent, so a patent application was filed in accordance with the law. However, the above-mentioned are only the preferred embodiments of the present invention, which cannot limit the scope of patent application in this case. All the equivalent modifications or changes made in accordance with the spirit of this new model by those who are familiar with the skills of this case shall be covered by the scope of the following patent applications.

100; 200: tubular heater 102; 202: Tubular base 104;204: Striped carbon nanotube layer 1042: Spiral ring structure 106;206: first electrode 108; 208: second electrode 143: Carbon Nanotube Fragment 145: Carbon Nanotube 204a: Part One 204b: Part Two 2042: first end 2044: second end

Fig. 1 is a schematic structural diagram of a tubular heater provided by the first embodiment of the new type.

Figure 2 is a schematic diagram of the strip-shaped carbon nanotube layer in the tubular heater provided by the first embodiment of the new invention.

Figure 3 is a scanning electron micrograph of the carbon nanotube layer in the tubular heater provided by the new model.

FIG. 4 is a schematic diagram of the structure of carbon nanotube segments in the carbon nanotube layer in FIG. 3.

Fig. 5 is a schematic structural diagram of another tubular heater provided by the first embodiment of the new type.

Fig. 6 is a schematic structural diagram of a tubular heater provided by a second embodiment of the new type.

Fig. 7 is a schematic diagram of the strip-shaped carbon nanotube layer in the tubular heater provided by the second embodiment of the new invention.

100: Tubular heater

102: Tubular substrate

104: Striped carbon nanotube layer

1042: Spiral ring structure

106: first electrode

108: second electrode

Claims (10)

A tubular heater includes a tubular substrate, a heating layer, and at least two electrodes. The heating layer includes a strip-shaped carbon nanotube layer, and the at least two electrodes are located on the strip-shaped carbon nanotube layer The improvement is that the strip-shaped carbon nanotube layer is spirally wound on the surface of the tubular substrate to form the heating layer, and the at least two electrodes are respectively disposed on two of the strip-shaped carbon nanotube layer At the end, the strip-shaped carbon nanotube layer includes a plurality of mutually parallel carbon nanotubes, and the extending direction of the plurality of carbon nanotubes is the same as the extending direction of the strip-shaped carbon nanotube layer. The tubular heater according to claim 1, wherein the strip-shaped carbon nanotube layer includes at least one layer of carbon nanotube drawn film, and the carbon nanotube drawn film is formed from a carbon nanotube array Pull the obtained carbon nanotube film. The tubular heater according to claim 2, wherein the drawn carbon nanotube film comprises a plurality of carbon nanotubes which are preferably oriented in the same direction and arranged parallel to the surface of the drawn carbon nanotube film, and The carbon tubes are connected end to end through van der Waals forces. The tubular heater according to claim 1, wherein when the strip-shaped carbon nanotube layer is wound on the tubular substrate, a plurality of spiral ring structures are formed. The tubular heater according to claim 4, wherein two adjacent spiral ring structures are arranged at intervals. The tubular heater according to claim 4, wherein two adjacent spiral ring structures are in contact with each other. A tubular heater includes a tubular substrate, a heating layer, and at least two electrodes. The heating layer includes a strip-shaped carbon nanotube layer, and the at least two electrodes are located on the strip-shaped carbon nanotube layer , Wherein the strip-shaped carbon nanotube layer is spirally wound around the surface of the tubular substrate to form the heating layer, and the strip-shaped carbon nanotube layer includes a plurality of carbon nanotubes parallel to each other, and The extending direction of the plurality of carbon nanotubes is the same as the extending direction of the strip-shaped carbon nanotube layer. The strip-shaped carbon nanotube layer includes a first end and a second end. The ribbon-shaped carbon nanotube layer is separated from the first end to form a first part and a second part. The first part and the second part are strip-shaped, and the first part and the second part are at the second end. Connect with each other. The tubular heater according to claim 7, wherein the at least two electrodes include a first electrode and a second electrode, and the first electrode and the second electrode are located on the first electrode of the strip-shaped carbon nanotube layer. One end is electrically connected to the first part and the second part respectively. The tubular heater according to claim 7, wherein, after the strip-shaped carbon nanotube layer is wound on the tubular substrate, the first part and the second part can be formed by cutting. The tubular heater according to claim 7, wherein when a voltage is applied between the first electrode and the second electrode, when the voltage of the first electrode is greater than that of the second electrode, the current flows from the first electrode to the first part along The length direction of the first part flows from the second end to the second part, along the length direction of the second part, to the second electrode; when the voltage of the first electrode is lower than the second electrode, the direction of the current is opposite.

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