Overheat steam generation device

Abstract

To propose an overheat stream generation device having less power consumption and enabling miniaturization.SOLUTION: An overheat stream generation device has a case 2, and is provided with: a steam generation unit 11 at a lower part of the case 2, which evaporates water using a first heating unit 7 to generate steam; a steam heating unit 15 in the case 2 and above the steam generation unit 11, which heats the steam generated in the steam generation unit 11 using a second heating unit 8; and a heat transfer section 16 in the steam heating unit 15, which transfers heat from the second heating unit 8 to the steam inside the steam heating unit. The heat transfer unit has a cylindrical part 16a and heat transfer fins 16b. The plurality of heat transfer fins 16b are provided at appropriate intervals in an axial direction of the case 2. A gap 18 is formed between the heat transfer fins 16b and an inner surface of the case 2. The heat transfer fin 16b has a plurality of flow holes 19a, 19b formed therein, which penetrate in the axial direction of the case 2.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a superheated steam generator. [Background technology]

[0002] 2. Description of the Related Art Steam superheaters are used industrially to generate steam by heating a liquid such as water, and to heat the steam to a predetermined temperature to obtain superheated steam.

[0003] In recent years, the high humidifying capacity of superheated steam has attracted attention, and it is also used as an indoor humidifier.

[0004] It has been proposed that this superheated steam generator comprises two ceramic heaters, one for steam generation and one for steam heating, arranged vertically on the same axis, with the steam generation heater heating water to generate steam, and the generated steam being further heated by the steam heating heater to obtain superheated steam (see Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 7153902 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the superheated steam generator described in Patent Document 1 above has a steam heating heater arranged vertically, and is designed to transfer heat directly to the water vapor rising along the surface of the steam heating heater. This results in a small contact area between the water vapor and the steam heating heater, making it impossible to transfer heat sufficiently to the water vapor, and resulting in the problem that the desired amount of superheated steam cannot be obtained.

[0007] In particular, when the amount of heat generated in the steam generating heater is small, the flow becomes laminar, and a boundary layer forms between the heater surface and the rising water, hindering heat transfer.

[0008] Therefore, in the above-mentioned conventional superheated steam generator, it becomes necessary to increase the heater output and heater surface area, which may lead to an increase in the amount of electric power required and an increase in the size of the entire device.

[0009] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a superheated steam generator that consumes less electricity and can be made compact. [Means for solving the problem]

[0010] In order to solve the above problems, the present invention provides a steam generator having a case and a steam generating section for evaporating water by a first heating section and generating steam at a lower portion of the case, A steam heating section is provided in the case and above the steam generating section, the steam heating section heating the steam generated in the steam generating section by a second heating section, and an exhaust port is formed on the upper side of the case for exhausting the steam heated by the steam heating section; a liquid supply unit for supplying liquid to the vapor generating unit; A heat transfer section is provided within the steam heating section to transfer heat from the second heating section to the steam therein, the heat transfer section having a cylindrical section with the second heating section tightly fitted thereto, and a plurality of plate-shaped heat transfer fins protruding outward from the cylindrical section are provided at appropriate intervals in the axial direction of the case, A gap is formed between the heat transfer fin and an inner surface of a case, The heat transfer fin is characterized in that a plurality of through holes are formed in the heat transfer fin, the through holes passing through the heat transfer fin in the axial direction of the case.

[0011] Furthermore, in each heat transfer fin, the total opening area of ​​the through holes may be larger than the opening area of ​​the gap between the outer end of each heat transfer fin and the inner surface of the case.

[0012] The distance between the heat transfer fins may be increased from the bottom to the top. Effect of the Invention

[0013] The present invention provides a heat transfer section that transfers heat from the second heating section to steam, the heat transfer section having a cylindrical section with the second heating section tightly fitted inside, and a plurality of plate-shaped heat transfer fins protruding outward from the cylindrical section are provided at appropriate intervals in the axial direction of the case, forming a gap between the heat transfer fins and the inner surface of the case, and a plurality of flow holes that penetrate the heat transfer fins in the axial direction of the case.By doing so, it is possible to extend the residence time of water vapor in the steam heating section compared to the above-mentioned conventional technology, and heat can be transferred sufficiently from the second heat transfer section to the water vapor.

[0014] This allows the superheated steam generator to consume less power and be made smaller than the conventional technology described above. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view of a superheated steam generator according to a first embodiment of the present invention. [Diagram 2] A longitudinal section of FIG. [Diagram 3] FIG. 2 is a perspective view of a heat transfer part used in the first embodiment of the present invention. [Figure 4] Top view of Figure 3. [Diagram 5] FIG. 11 is a perspective view of an example of a heat transfer part used in Example 2 of the present invention. [Figure 6] FIG. 5 is a longitudinal cross-sectional view. [Figure 7] FIG. 11 is a perspective view of another example of the heat transfer portion used in the second embodiment of the present invention. [Figure 8] FIG. 7 is a longitudinal cross-sectional view. [Figure 9] FIG. 11 is a perspective view of another example of the heat transfer portion used in the second embodiment of the present invention. [Figure 10] FIG. 10 is a longitudinal cross-sectional view of FIG. [Figure 11] FIG. 11 is a perspective view of another example of the heat transfer portion used in the second embodiment of the present invention. [Figure 12] FIG. 11 is a perspective view of another example of the heat transfer portion used in the second embodiment of the present invention. [Figure 13] FIG. 11 is a perspective view of another example of the heat transfer portion used in the second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a superheated steam generator according to the present invention will be described with reference to the examples shown in the drawings.

[0017] [Example 1] FIG. 1 is a perspective view of a superheated steam generator 1 according to a first embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of FIG. 1, with a portion of the internal structure omitted.

[0018] 1, the superheated steam generator 1 has a cylindrical case 2, and the cross-sectional shape of the case 2 can be formed arbitrarily, and in this embodiment, the cross section of the case 2 is circular and the case 2 is formed cylindrical. Flanges 3 and 4 are fixed to both ends of the case 2 in the axial direction, protruding outward in the radial direction centered on the axis of the case 2.

[0019] A lower flange 5 is removably attached to the lower flange 3 by means of bolts 3a, and a gasket 3b is provided between the flange 3 and the lower flange 5.

[0020] 2, a first overheating portion 7 is fixed to the center of the lower flange 5 so as to protrude toward the inside of the case 2. For example, a cartridge heater or a ceramic heater can be used as the first overheating portion 7, and a cartridge heater was used in this embodiment.

[0021] An upper flange 6 is removably fixed to the flange 4 using bolts 4a, and a gasket 4b is provided between the flange 4 and the upper flange 6. As shown in Fig. 2, a second overheating part 8 is fixed to the center of the upper flange 6 so as to protrude toward the inside of the case 2. For example, a cartridge heater or a ceramic heater can be used as the second overheating part 8, and a cartridge heater was used in this embodiment.

[0022] A water storage section 10 is formed between the inner wall of the case 2 and the first overheating section 7. As shown in Fig. 2, a liquid supply section 9 that supplies a liquid such as water to the inside of the water storage section 10 is provided in the axial center of the case 2, and water is stored in the water storage section 10.

[0023] The water in the water storage unit 10 is superheated by the first superheating unit 7 until it evaporates. The first superheating unit 7 and the water storage unit 10 constitute a steam generating unit 11, which is provided in the lower part of the case 2 and evaporates the water by the first superheating unit 7 to generate steam.

[0024] Above liquid supply portion 9 of case 2, a plurality of pins serving as positioning members 12 protruding inward from the inner wall of case 2 are fixed in the circumferential direction.

[0025] As shown in Figure 2, a space 13 is formed between the inner wall of case 2 and the second superheating section 8, and the second superheating section 8 and the space 13 form a steam superheating section 15. The steam superheating section 15, which superheats steam using the second superheating section 8, is provided within case 2 and above the steam generation section 11.

[0026] A heat transfer section 16 is disposed within the steam superheating section 15, and the heat transfer section 16 is positioned by a positioning member 12 so as not to move below the positioning member 12.

[0027] 2 and 3, the heat transfer section 16 has a cylindrical section 16a, and a plurality of plate-shaped heat transfer fins 16b protruding outward from the cylindrical section 16a are provided at appropriate intervals in the axial direction of the case 2. The second overheating section 8 is housed inside the cylindrical section 16a.

[0028] The number of heat transfer fins 16b is five in this embodiment, but can be set to any number as long as there is more than one.

[0029] As shown in FIGS. 2 and 3, it is preferable that the interval between the heat transfer fins 16b, 16b gradually becomes wider from the bottom to the top.

[0030] The cylindrical portion 16a has a storage space formed therein that opens in the vertical direction, and the second overheating portion 8 is stored in this storage space so as to be tightly fitted therein. The cross-sectional shape of the cylindrical portion 16a can be formed arbitrarily, and in this embodiment, it is formed into a circular shape.

[0031] The upper surface of the heat transfer fin 16b can be formed in any shape, but in this embodiment, it is formed in a circular shape. A through hole is formed in the center of the heat transfer fin 16b, and the cylindrical portion 16a is inserted and fixed to each other.

[0032] A gap 18 is formed between the outer ends of the heat transfer fins 16 b and the inner wall of the case 2 .

[0033] As shown in Fig. 3 and Fig. 4, a plurality of rectangular through holes 19a and a plurality of triangular through holes 19b are formed penetrating the heat transfer fin 16b in the front-to-back direction. A plurality of triangular through holes 19a are formed in the heat transfer fin 16b in the circumferential direction around the center of the heat transfer fin 16b, and a plurality of rectangular through holes 19b are formed in the circumferential direction on the radial outside of the through holes 19a around the center of the heat transfer fin 16b. The number of triangular through holes 19a and the number of rectangular through holes 19b are formed to be the same.

[0034] The triangular through hole 19a and the rectangular through hole 19b do not communicate with each other, and a part of the plate material constituting the heat transfer fin 16b is disposed therebetween.

[0035] It is preferable that the centers of the flow holes 19a, 19b are not aligned in a straight line in the axial direction of the tubular portion 16a, and as shown in Figure 3, adjacent heat transfer fins 16b, 16b are arranged in a state where they are rotated by a predetermined angle in the circumferential direction relative to each other.

[0036] In each heat transfer fin 16 b , the total opening area of ​​the through holes 19 a , 19 b is set to be larger than the opening area of ​​the gap 18 between each heat transfer fin 16 b and the inner surface of the case 2 .

[0037] The water vapor formed in the steam generating section 11 is further superheated by the second superheating section 8 to become superheated water vapor.

[0038] An exhaust port 21 is formed in the upper flange 6. The superheated steam is heated to a predetermined temperature by the second heating unit 8 and is exhausted from the exhaust port 21. In this embodiment, the temperature of the exhausted superheated steam is adjusted between 100 and 300°C depending on the outside air temperature and humidity.

[0039] By providing multiple heat transfer fins 16b, the residence time of water vapor in steam heating section 15 can be made longer than in the above-mentioned conventional technology, and even if the axial length of steam generating section 11 is made shorter than in the above-mentioned conventional technology, a sufficient amount of heat transfer from second heating section 8 to water vapor can be ensured, superheated steam generator 1 can be made smaller, superheated steam at a predetermined temperature can be discharged from outlet 21, and a sufficient amount of superheated steam can be supplied. Furthermore, even if low-output, inexpensive heating devices with smaller output and surface area than the above-mentioned conventional technology are used for heating sections 7 and 8 used in superheated steam generator 1, equivalent performance can be achieved, and electricity consumption and costs can be significantly reduced.

[0040] By forming a gap 18 between the heat transfer fin 16b and the inner surface of the case 2 and forming multiple circulation holes 19a, 19b in the heat transfer fin 16b, the contact area and contact time between the heat transfer fin 16b and the water vapor can be increased, and heat can be efficiently transferred from the second heating section 8 to the water vapor.

[0041] In each heat transfer fin 16b, the total opening area of ​​the circulation holes 19a, 19b is made larger than the opening area of ​​the gap 18 between the heat transfer fin 16b and the inner surface of the case 2, so that the amount of water vapor flowing through the circulation holes 19a, 19b is made larger than the amount of water vapor flowing through the gap 18, and the contact area and contact time between the heat transfer fin 16b and the water vapor are increased.

[0042] When a cartridge heater is used as the second heating section 8, the temperature of the second heating section 8 is lower at the lower tip side than at the upper base side, so by gradually widening the spacing between the heat transfer fins 16b, 16b from the bottom to the top, the heat of the second heating section can be efficiently transferred to the water vapor.

[0043] The superheated steam generator 1 of the present invention can be used as a humidifier for humidifying the interior of a room or a vehicle.

[0044] [Example 2] In the first embodiment, each heat transfer fin 16b has a plurality of triangular through holes 19a and a plurality of rectangular through holes 19b, but the through holes may be formed in any shape in each heat transfer fin 16b. Also, the inner end 16c and the outer end 16d of the heat transfer fin 16b may be bent downward to form ribs, as shown in Figs. 5 and 6.

[0045] 7 and 8, each heat transfer fin 16b may be formed with a plurality of circular through holes 30. It is preferable that the centers of the through holes 30 formed in each heat transfer fin 16b are not aligned in a straight line in the axial direction of the tubular portion 16a.

[0046] As shown in Figs. 9 and 10, the through hole 30 may be formed by burring so that a cylindrical portion 30a is formed around the through hole 30.

[0047] 11, a plurality of arc-shaped through holes 32 may be formed in each heat transfer fin 16b in the circumferential direction around the center of the heat transfer fin 16b, and a plurality of arc-shaped through holes 32 may be provided in the radial direction of the center of the heat transfer fin 16b. It is preferable that the centers of the through holes 32 formed in each heat transfer fin 16b are not aligned in a straight line in the axial direction of the cylindrical portion 16a.

[0048] The above-mentioned communication holes 19a, 19b, 30, and 32 may be appropriately combined as shown in FIGS.

[0049] The other structure is the same as in the first embodiment, so the description thereof will be omitted.

[0050] In the second embodiment, the same actions and effects as those of the first embodiment are achieved. [Explanation of symbols]

[0051] 1. Superheated steam generator 2 Cases 7 1st heating section 8 Second heating section 9 Liquid supply section 11 Steam generation section 15 Steam heating section 16 Heat transfer section 16a Cylinder part 16b Heat transfer fin 18 void 19a,19b,30,32 Distribution hole 21 Outlet

Claims

1. a steam generating unit that evaporates water by a first heating unit and generates steam at a lower portion of the case; A steam heating section is provided in the case and above the steam generating section, the steam heating section heating the steam generated in the steam generating section by a second heating section, and an exhaust port is formed on the upper side of the case for exhausting the steam heated by the steam heating section; a liquid supply unit for supplying liquid to the vapor generating unit; A heat transfer section is provided within the steam heating section to transfer heat from the second heating section to the steam therein, the heat transfer section having a cylindrical section with the second heating section tightly fitted thereto, and a plurality of plate-shaped heat transfer fins protruding outward from the cylindrical section are provided at appropriate intervals in the axial direction of the case, A gap is formed between the heat transfer fin and an inner surface of a case, A superheated steam generator characterized in that the heat transfer fins are formed with a plurality of flow holes passing through in the axial direction of the case.

2. 2. The superheated steam generator according to claim 1, wherein the total opening area of ​​the through holes in each heat transfer fin is larger than the opening area of ​​the gap between the outer end of each heat transfer fin and the inner surface of the case.

3. 3. The superheated steam generator according to claim 1, wherein the intervals between the heat transfer fins are made wider from the bottom to the top.

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