Heat exchanger of heating device

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 specifically, to a heat exchanger for a heating device that has high-density fins with excellent heat exchange efficiency despite its simple structure, and can be manufactured and operated at low cost. [Background technology]

[0002] As is well known, in agricultural greenhouse cultivation, heating devices are used to control the indoor temperature inside the greenhouse. However, in recent years, fuel costs have continued to rise due to changes in the global situation, etc., and in order to continue supplying agricultural products at stable prices, it is essential to reduce heating costs.

[0003] 2. Description of the Related Art Conventionally, as a heat exchanger for heating gas, generally, one in which heatable fins are provided on the inside of a pipe in a gas flow path has been disclosed (for example, see 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 with which the gas comes into contact, resulting in poor heat exchange efficiency.

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

[0007] [Patent Document 1] JP 2008-8549 A Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made in consideration of the above-mentioned problems with conventional heat exchangers, and has an object to provide a heat exchanger for a heating device that has a simple structure but high-density fins with 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 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 a thermally conductive metal plate 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 is such that, when the fin 1 is unfolded, vertical surfaces 11 of different heights are formed in a comb-like shape, and outer side surfaces 12 bent in a U-shape are formed at the bases of the vertical surfaces 11, respectively. The fin 1 is wound in a substantially circumferential shape with the outer peripheral surface portion 12 facing outward and is 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 portions of the vertical surfaces 11 are butted together symmetrically near the center and folded over.

[0011] In addition to the above-mentioned means, the present invention provides a method for solving the above-mentioned problems by forming the vertical surface 11 of the fin 1 into three levels of height: a highest vertical surface 11A, a neutral surface 11B at an intermediate height, and a lowest low vertical surface 11C. It is also possible to adopt a technical measure in which high elevations 11A and neutral surfaces 11B are arranged alternately with low elevations 11C sandwiched between them, forming a repeating unit of high elevation - low elevation - neutral surface - low elevation -...

[0012] Furthermore, in order to solve the above problems, the present invention can also adopt, in addition to the above means, a technical measure in which the vertical surface 11 of the fin 1 is formed by bending a strip-shaped plate back to back, as necessary.

[0013] Furthermore, in order to solve the above problems, the present invention can also adopt, in addition to the above means, a technical measure of providing multiple jacket-type heat sources 3 on the outer peripheral surface of the integrally molded cylinder 2, as necessary. Effect 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 side surfaces bent in a U-shape are formed at the bases of the vertical surfaces, and the fin is wound in a substantially circumferential shape with the outer peripheral surfaces on the outside and is placed inside the internal space of the cylinder, By configuring the outer surface portion to abut against the inner surface of the cylinder and the tip portions of the vertical surfaces to be butted together near the center, it is possible to concentrate the fins at a high density near the center of the cylinder. The flow velocity distribution within the cylindrical pipe becomes faster near the center, thereby improving the heating efficiency of the gas.

[0015] The invention also makes clever use of the fin's elastically deformable material properties. If fin 1 were a uniform shape, as when formed by extrusion molding or injection molding, high precision in size would be required to match the inner surface of the cylinder. However, in the present invention, the elastic deformation of the fin creates a biasing force that tries to expand outward, which acts to push against the cylinder, thereby increasing the fin's shape stability and allowing it to be securely held inside the cylinder. [Brief description 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. [Diagram 2] FIG. 2 is a cross-sectional view showing a rolled up state of the fin according to the embodiment of the present invention. [Diagram 3] 1 is an explanatory cross-sectional view showing a 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 PREFERRED EMBODIMENTS

[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 of a thermally conductive metal plate are disposed in the internal space of the cylinder 2. As the thermally conductive metal used for the fins 1 and the cylinder 2, aluminum, copper, etc. can be adopted, but aluminum is preferable 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 circumferential surface of the cylinder 2. More specifically, the structure is such that an electric heating wire is embedded inside a cylindrical ceramic or other insulator, and a heat insulating material is arranged on the outside of the insulator, so that radiant heat can be concentrated and generated on the inner surface of the insulator, and further, 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, the heating response is fast, hot air can be generated quickly, and the generation of carbon dioxide can be significantly reduced.

[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: about 25 cm) without using a large one, improving the freedom of device design and making it possible to easily adjust the heating temperature by independently controlling the heat sources 3.

[0021] Next, a description will be given of 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 shape, while outer side surface portions 12 bent in a U-shape are formed at the base of each of the 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 since it is only necessary to bend one strip-shaped plate, and also makes it possible to create small gaps between the plates to further increase the surface area.

[0023] Then, as shown in Fig. 2, the fin 1 is wound in a generally circumferential shape with the outer peripheral surface portion 12 facing outward. In this case, the fin 1 is preferably a single member, but may be a member formed by joining a plurality of members into a generally circumferential shape. The fin 1 in this wound state is placed inside the internal space of the cylinder 2. In this manner, the outer peripheral surface portion 12 of the fin 1 comes into contact with the inner peripheral surface of the cylinder 2, so that heat from the cylinder 2 can be directly conducted to the outer peripheral surface portion 12.

[0024] The outer peripheral surface portion 12 is abutted against the inner peripheral surface 21 of the cylinder 2, and the tip portions of the vertical surfaces 11 are folded over and butted together 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, the heating efficiency of the gas can be improved by concentrating the fins 1 at a high density near the center. In this embodiment, it is particularly preferable to fold over and butt together in a symmetrical arrangement.

[0025] Furthermore, a heat insulating material 4 is wrapped around the outer circumference 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 a fastener such as a band.

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

[0027] By configuring 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 the density of the fins 1 near the center of the cylinder 2 can be more efficiently improved.

[0028] In addition, the elastically deformable material properties of the fin 1 are cleverly utilized. If the fin 1 were a uniform shape formed by extrusion molding or injection molding, precision in size would be required to match the inner surface of the cylinder 2. However, in the present invention, the elastic deformation of the fin 1 creates a biasing force that causes the rolled fin 1 to expand outward, creating a tensioning action against the cylinder 2. This increases the shape stability of the fin 1 and enables it to be securely held inside the cylinder 2.

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

[0030] Specifically, the heating device can be used by starting the heat source 3 and blower 5 (blower motor), which sends air into the duct 6, where it is heat exchanged with the fins 1 inside the heated cylinder 2, and hot air is discharged from the outlet. The outlet of the duct 6 can be of a movable oscillating type that allows easy adjustment of the blowing direction, or it can be of a tapered (megaphone-like) type that is enlarged, or of a type that branches 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 a high temperature of 700°C or more. Therefore, by adjusting the airflow rate of the blower 5, damage or breakdown due to overheating can be prevented.

[0032] In addition, the position where the heat exchanger is fixed in the heating device (the orientation of the cylinder 2) may be vertical or horizontal. In addition, 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 appropriately adjusted to adjust the temperature.

[0033] The present invention is generally configured as described above, however, the present invention is by no means 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, so long as they can be concentrated in high density near the center of the cylinder 2.

[0034] Furthermore, as long as the fin 1 has the structure of the present invention, 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 Cylinder 21 Inner surface 3 Heat source 4. Insulation 5. Blower 6 Duct

Claims

1. A heat exchanger for a heating device capable of heating gas passing through a cylinder made of a thermally conductive metal with fins and discharging hot air, The cylinder has fins formed of thermally conductive metal plates disposed in an internal space thereof, and a heat source capable of heating the cylinder body is attached to the exterior thereof; The fin structure is such that, when the fin is unfolded, vertical surfaces of different heights are formed in a comb-like shape, and at the base of each of the vertical surfaces, an outer side surface portion is formed that is bent in a U-shape, The fins are wound in a substantially circumferential shape with the outer peripheral surface portions facing outward and are fitted inside the internal space of the cylinder, 1 is a cross-sectional view of a heat exchanger according to a first embodiment of the present invention; FIG. 2 is a cross-sectional view of a heat exchanger according to a first embodiment of the present invention;

2. The elevation of the fin has three levels of height: a highest elevation, a neutral surface at an intermediate height, and a lowest elevation, 2. A heat exchanger for a heating system according to claim 1, characterized in that the high elevations and neutral surfaces are arranged alternately with low elevations sandwiched between them, and are formed by repeating a unit of high elevation - low elevation - neutral surface - low elevation -...

3. 2. A heat exchanger for a heating apparatus according to claim 1, wherein the vertical surfaces of said fins are formed by bending strip-shaped plates back to back.

4. 2. The heat exchanger for a heating apparatus according to claim 1, wherein a plurality of jacket-type heat sources are provided on an outer circumferential surface of the integrally molded cylinder.

Images