Heat exchanger for heating equipment

Abstract

To provide a heat exchanger of a heating device which includes a high density fin which excels in heat exchange efficiency while having a simple structure, and which can be manufactured and operated at low cost.SOLUTION: A heat exchanger of a heating device can deliver hot air by heating a gas passing in a cylinder 2 made of heat conductive metal by a fin 1. In the cylinder 2, the fin 1 formed by a plate body made of heat conductive metal is disposed in an internal space, and a heat source 3 capable of heating the body of the cylinder is externally mounted. The structure of the fin 1 is constituted in such a manner that, when the fin 1 is developed, vertical surfaces 11 of different heights are formed in a comb-like shape, and at a base part of the vertical surfaces, an outside surface part 12 bent in a U-shape is formed respectively. The fin 1 is internally mounted in the internal space of the cylinder 2 in a state where an outer peripheral surface part 12 is on the outside and where the fin is wound in a substantially circumferential shape, and the outer peripheral surface part 12 comes into contact with an inner peripheral surface 21 of the cylinder 2, and tip parts of the vertical surfaces 11 are abutted symmetrically in the vicinity of the center and folded and overlapped.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an improvement in a heat exchanger, and more particularly to a heat exchanger for a heating device that has a simple structure but high-density fins that provide excellent heat exchange efficiency, and can be manufactured and operated at low cost. [Background technology]

[0002] As is well known, heating devices are used to control the temperature inside greenhouses in agricultural greenhouses, etc. However, in recent years, fuel costs have continued to rise due to changes in the global situation, etc., and reducing heating costs is essential to continuing to supply agricultural products at stable prices.

[0003] BACKGROUND ART Conventionally, heat exchangers for heating gas have generally been disclosed in which heatable fins are provided inside a pipe in a gas flow path (see, for example, Patent Document 1).

[0004] However, in the heat exchanger described in Patent Document 1, although fin members made by rolling corrugated fins are inserted into the tube body, they need to be tightly fixed by brazing, which may complicate the manufacturing process and increase manufacturing costs.

[0005] Furthermore, with corrugated fins, the density of the fins inside the pipe is low, which reduces the surface area that comes into contact with the gas, resulting in poor heat exchange efficiency.

[0006] However, conversely, simply increasing the density of the fins inside the pipe to increase the surface area would result in a trade-off, which would cause resistance to the airflow, and would also require the design of a complex fin shape, which could also lead to increased manufacturing costs. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-8549 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention was made in consideration of the above-mentioned problems with conventional heat exchangers, and its purpose is to provide a heat exchanger for a heating device that has a simple structure but is equipped with high-density fins that provide excellent heat exchange efficiency, and can be manufactured and operated at low cost. [Means for solving the problem]

[0009] The means adopted by the present inventor to solve the above technical problems will be described below with reference to the accompanying drawings.

[0010] That is, the present invention is a heat exchanger for a heating device that can heat gas passing through a cylinder 2 made of a thermally conductive metal with fins 1 and send out hot air, The cylinder 2 has fins 1 formed of thermally conductive metal plates disposed in the internal space, and a heat source 3 capable of heating the body of the cylinder 2 is attached to the exterior. The structure of the fin 1, when the fin 1 is deployed, is as follows: The vertical surface 11 of the fin 1 is made to have three levels of height: the highest high vertical surface 11A, the middle neutral surface 11B, and the lowest low vertical surface 11C. The high elevation 11A and the neutral surface 11B are alternately arranged with the low elevation 11C sandwiched therebetween, and are formed by repeating the unit of high elevation - low elevation - neutral surface - low elevation - .... The vertical surfaces 11 of different heights are formed in a comb-like shape, and the bases of these vertical surfaces 11 are each formed with an outer surface portion 12 that is bent in a U-shape. The fins 1 are wound in a substantially circumferential shape with the outer peripheral surface portions 12 facing outward and are then placed inside the internal space of the cylinder 2. The heat exchanger for the heating device was completed by adopting a technical means in which the outer peripheral surface portion 12 is abutted against the inner peripheral surface 21 of the cylinder 2 and the tip ends of the vertical surfaces 11 are butted together symmetrically near the center and folded over.

[0011] The present invention also provides a heat exchanger for a heating device capable of heating gas passing through a cylinder 2 made of a thermally conductive metal with fins 1 and discharging hot air, The cylinder 2 has fins 1 formed of thermally conductive metal plates disposed in the internal space thereof, and a plurality of jacket-type heat sources 3 capable of heating the cylinder body are provided on the outer circumferential surface of the integrally molded cylinder 2, The structure of the fin 1 is such that, when the fin 1 is unfolded, vertical surfaces 11 of different heights are formed in a comb-like shape, and outer surface portions 12 bent in a U-shape are formed at the bases of these vertical surfaces 11, respectively. The fins 1 are wound in a substantially circumferential shape with the outer peripheral surface portions 12 facing outward and are then placed inside the internal space of the cylinder 2. The heat exchanger for the heating device was completed by adopting a technical means in which the outer peripheral surface portion 12 is abutted against the inner peripheral surface 21 of the cylinder 2 and the tip ends of the vertical surfaces 11 are butted together symmetrically near the center and folded over. [Effects of the Invention]

[0014] In the present invention, the fin structure is such that, when the fin is unfolded, vertical surfaces of different heights are formed in a comb-like shape, and outer surface portions that are bent in a U-shape are formed at the bases of these vertical surfaces, and the fin is placed inside the internal space of the cylinder in a state where it is wound in a substantially circumferential shape with these outer peripheral surface portions facing outward, By configuring the outer surface portion to abut against the inner surface of the cylinder and the tip of the vertical surface to butt together and overlap near the center, it is possible to concentrate the fins at a high density near the center of the cylinder, and the flow velocity distribution within the cylindrical pipe becomes faster near the center, thereby improving the heating efficiency of the gas.

[0015] In addition, the elastically deformable material properties of the fins are cleverly utilized. If the fins 1 were to have a uniform shape, such as when formed by extrusion molding or injection molding, precision in the size of the fins would be required to match the inner surface of the cylinder. However, in the present invention, the elastic deformation of the fins creates a biasing force that tries to expand outward, which acts to tension the cylinder, thereby increasing the shape stability of the fins and allowing them to be securely held inside the cylinder. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 2 is a perspective view showing a deployed state of a fin according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view showing a state in which the fin of the embodiment of the present invention is wound. [Figure 3] 1 is an explanatory cross-sectional view showing the structure of a heat exchanger according to an embodiment of the present invention. [Figure 4] 1 is an overall schematic diagram showing a heating device according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0017] An embodiment of the present invention will be described with reference to Figures 1 to 4. The present invention is a heat exchanger for a heating device that can heat gas passing through a cylinder 2 made of a thermally conductive metal with fins 1 and send out hot air.

[0018] First, fins 1 formed from thermally conductive metal plates are disposed in the internal space of the cylinder 2. Aluminum, copper, etc. can be used as the thermally conductive metal for the fins 1 and the cylinder 2, but aluminum is preferred from the viewpoints of cost and ease of processing.

[0019] The cylinder 2 is also fitted with a heat source 3 capable of heating the body of the cylinder 2. In this embodiment, a jacket-type heat source 3 can be used that can be fixed in close contact with the entire outer surface of the cylinder 2. More specifically, this structure has an electric heating wire embedded inside a cylindrical ceramic or other insulating body, and an insulating material disposed on the outside of the insulator, allowing radiant heat to be concentrated on the inner surface of the insulator, and the cylinder 2 can be fastened and fixed with a band or the like. In this way, when the heat source 3 is an electric heating type, power can be supplied from a 200V power outlet, and it has a fast heating response, can quickly generate hot air, and can significantly reduce carbon dioxide emissions.

[0020] In this embodiment, a plurality of jacket-type heat sources 3 can be provided on the outer circumferential surface of the integrally molded cylinder 2. Such a long, integrally molded cylinder 2 can prevent the heat conduction from being interrupted by a joint, and can use a compact heat source 3 (length: approximately 25 cm) without using a large one, thereby improving the flexibility of device design and making it possible to easily adjust the heating temperature by independently controlling the heat sources 3.

[0021] Next, we will explain the structure of the fin 1. As shown in Fig. 1, when the fin 1 is unfolded, the structure of the fin 1 is such that vertical surfaces 11 of different heights are formed in a comb-like shape, and a U-shaped outer surface portion 12 is formed at the base of each of these vertical surfaces 11. In this embodiment, the vertical surfaces 11 are formed at approximately equal intervals.

[0022] In this embodiment, the vertical surface 11 of the fin 1 can be formed by bending a strip-shaped plate back to back. This makes it possible to handle and process the material easily because it is only necessary to bend one strip-shaped plate, and also creates small gaps between the plates, which further increases the surface area.

[0023] Then, as shown in Figure 2, the fins 1 are wound in a generally circumferential shape with the outer peripheral surface portions 12 facing outward. In this case, the fins 1 are preferably made of a single member, but may also be made of multiple members joined together to form a generally circumferential shape. The fins 1 are then placed in the interior space of the cylinder 2 in this wound state. In this way, the outer peripheral surface portions 12 of the fins 1 come into contact with the inner peripheral surface of the cylinder 2, allowing heat from the cylinder 2 to be directly conducted to the outer peripheral surface portions 12.

[0024] Furthermore, the outer peripheral surface portion 12 is abutted against the inner peripheral surface 21 of the cylinder 2, and the tip ends of the vertical surfaces 11 are configured to butt and overlap near the center (see FIGS. 2 and 3). That is, since the gas flow velocity distribution in the pipe of the cylinder 2 is faster near the center, by concentrating the fins 1 at high density near the center, the heating efficiency of the gas can be improved. In this embodiment, it is particularly preferable to butt and overlap in a symmetrical arrangement.

[0025] Furthermore, a heat insulating material 4 is wrapped around the outer periphery of the heat source 3. This heat insulating material 4 can be made of nonwoven fabric such as rock wool or glass wool, or a composite material combining these with aluminum foil, and is firmly fixed in place with fasteners such as bands.

[0026] In this embodiment, the elevation 11 of the fin 1 is formed into three levels of height: the highest elevation 11A, a neutral surface 11B of intermediate height, and the lowest low elevation 11C. The high elevation 11A and the neutral surface 11B are arranged alternately with the low elevation 11C sandwiched between them, and the fin can be formed by repeating the unit high elevation - low elevation - neutral surface - low elevation -...

[0027] By configuring the fins 1 in this manner, interference between the vertical surfaces 11 when the fins 1 are wound in an approximately circumferential shape can be prevented, making it easier to butt them together symmetrically near the center of the cylinder 2, and more efficiently improving the density of the fins 1 near the center of the cylinder 2.

[0028] In addition, the elastically deformable material properties of the fin 1 are cleverly utilized. If the fin 1 were to have a uniform shape, such as when formed by extrusion molding or injection molding, precision in sizing would be required to match the inner surface of the cylinder 2. However, in the present invention, the elastic deformation of the fin 1 causes the rolled fin 1 to expand outward, which creates a tensioning effect on the cylinder 2, thereby increasing the shape stability of the fin 1 and allowing it to be securely held inside the cylinder 2.

[0029] Using the heat exchanger formed as described above, a heating system such as the one shown in Figure 4 can be constructed. This system does not require large-scale installation work or capital investment, and can be installed as a stationary unit. Furthermore, by converting the energy into electrical energy, carbon dioxide emissions can be significantly reduced.

[0030] The specific method of using the heating device is that when the heat source 3 and the blower 5 (blower motor) are started, air is sent into the duct 6, where it is heat exchanged with the fins 1 inside the heated cylinder 2, and the hot air is then discharged from the outlet. The outlet of the duct 6 can be a movable, oscillating type that makes it easy to adjust the direction of airflow, or it can be tapered (megaphone-shaped), expanded, or branched into two or three branches.

[0031] Depending on the type and thickness of the material, the fins 1 may melt or burn if the output of the heat source 3 reaches temperatures of 700°C or higher. Therefore, by adjusting the airflow rate of the blower 5, damage or breakdown due to overheating can be prevented.

[0032] Furthermore, the position at which the heat exchanger is fixed in the heating device (the orientation of the cylinder 2) may be vertical or horizontal. Also, since there is a risk of burns if the hot air blown out from the outlet of the duct 6 becomes too hot, the overall length and flow path shape of the duct 6 can be adjusted appropriately to adjust the temperature.

[0033] The present invention is generally configured as described above, but is in no way limited to the illustrated embodiment, and various modifications are possible within the scope of the claims. For example, the arrangement of the heights of the vertical surfaces 11 of the fins 1 is not limited to being symmetrical, and may be irregular, as long as they can be concentrated at high density near the center of the cylinder 2.

[0034] Furthermore, as long as the fin 1 of the present invention has the structure, the heat source 3 is not limited to an electric heating type, but can also be a combustion type such as gas or oil, and any of these fall within the technical scope of the present invention. [Explanation of symbols]

[0035] 1 Fin 11 Elevation 11A High elevation 11B Neutral plane 11C Low elevation 12 External surface 2 cylinders 21 Inner surface 3 Heat source 4. Insulation 5. Blower 6 Duct

Claims

1. A heat exchanger for a heating device that can heat gas passing through a cylinder made of a thermally conductive metal with fins and send out hot air, The cylinder has fins formed of thermally conductive metal plates arranged in an internal space, and a heat source capable of heating the main body of the cylinder is attached to the exterior, The fin structure is such that when the fin is deployed, the elevation of the fin has three levels of height: the highest elevation, a neutral surface at an intermediate height, and a low elevation, High elevations and neutral surfaces are alternately arranged with low elevations sandwiched between them, and are formed by repeating the unit of high elevation - low elevation - neutral surface - low elevation - .... The elevations of different heights are formed in a comb-like shape, while the bases of these elevations each have an outer surface portion that is bent in a U-shape, and The fins are wound in a substantially circumferential shape with the outer peripheral surface portions facing outward and are installed inside the internal space of the cylinder, A heat exchanger for a heating device, characterized in that the outer surface portion abuts the inner surface of the cylinder, and the tip ends of the vertical surfaces are butted together near the center and folded over.

2. A heat exchanger for a heating device that can heat gas passing through a cylinder made of a thermally conductive metal with fins and send out hot air, The cylinder has fins formed of thermally conductive metal plates arranged in an internal space, while a plurality of jacket-type heat sources capable of heating the main body of the cylinder are provided on the outer circumferential surface of the integrally molded cylinder, The fin structure has vertical surfaces of different heights formed in a comb-like shape when the fin is unfolded, and a U-shaped outer surface portion is formed at the base of each vertical surface, and The fins are wound in a substantially circumferential shape with the outer peripheral surface portions facing outward and are installed inside the internal space of the cylinder, A heat exchanger for a heating device, characterized in that the outer surface portion abuts the inner surface of the cylinder, and the tip ends of the vertical surfaces are butted together near the center and folded over.

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