Gas phase type heating method and gas phase type heating device
11262129 · 2022-03-01
Assignee
Inventors
Cpc classification
F27D7/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F27D3/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
H05B2203/022
ELECTRICITY
F27D2019/0006
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F27D2009/0002
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F27D7/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F27D3/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A gas phase type heating method includes loading an object into a vapor heating furnace or a heating furnace via a loading/unloading portion, cooling vapor of a heat transfer liquid by a cooler provided above the loading/unloading portion in the vapor heating furnace, and causing a gas to go in and out, making a pressure in a continuous furnace uniform, and heating the loaded object, by a connection portion that is provided above the cooler and has a pressure loss smaller than a pressure loss of the loading/unloading portion.
Claims
1. A gas phase type heating method of heating an object by a continuous furnace including a vapor heating furnace that heats the object by using latent heat of condensation of vapor of a heat transfer liquid and a heating furnace that communicates with the vapor heating furnace, the method comprising: loading the object into the vapor heating furnace or the heating furnace via a loading/unloading portion that allows the vapor heating furnace and the heating furnace to communicate with each other; cooling the vapor of the heat transfer liquid by a cooler provided above the loading/unloading portion in the vapor heating furnace; and causing a gas to go in and out between the vapor heating furnace and the heating furnace, making a pressure in the continuous furnace uniform, and heating the loaded object, by a connection portion that is provided above the cooler, allows the vapor heating furnace and the heating furnace to communicate with each other, and has a pressure loss smaller than a pressure loss of the loading/unloading portion.
2. The gas phase type heating method of claim 1, wherein a tub that heats the heat transfer liquid and generates the vapor is disposed in a lower portion of the vapor heating furnace.
3. A gas phase type heating device comprising: a continuous furnace, which heats an object, including: a vapor heating furnace heating the object by using latent heat of condensation of vapor of a heat transfer liquid; and a heating furnace communicating with the vapor heating furnace, and, wherein the vapor heating furnace includes a loading/unloading portion that communicates with the heating furnace, a cooler that is disposed above the loading/unloading portion and cools the vapor of the heat transfer liquid, and a connection portion that is disposed above the cooler, allows the vapor heating furnace and the heating furnace to communicate with each other, allows a gas to go in and out between the vapor heating furnace and the heating furnace, and has a pressure loss smaller than a pressure loss of the loading/unloading portion.
4. The gas phase type heating device of claim 3, wherein a tub that heats the heat transfer liquid and generates the vapor is disposed in a lower portion of the vapor heating furnace.
5. The gas phase type heating device of claim 3, wherein an opening area of a longitudinal section of the connection portion is larger than an opening area of a longitudinal section of the loading/unloading portion.
6. The gas phase type heating device of claim 3, wherein when a side close to an inlet through which the object is loaded is defined as an upstream side, and a side close to an outlet through which the object is unloaded is defined as a downstream side, an inlet loss on the upstream side of the connection portion and an inlet loss on the downstream side of the connection portion are the same.
7. The gas phase type heating device of claim 3, wherein the connection portion has an opening surrounded by an inclined or curved surface with respect to a long-axis direction of the connection portion, and by the loading/unloading portion having an opening surrounded by a surface orthogonal to a long-axis direction of the loading/unloading portion, the connection portion is configured to have a pressure loss smaller than a pressure loss of the loading/unloading portion.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
(20) In the configuration of Japanese Patent Unexamined Publication No. S60-108163, in a case of a device in which the vapor heating furnace is configured by only one single zone, an operation of taking in air flow from outside and confining vapor of a heat transfer liquid in the vapor heating furnace by air flow control is possible as described above.
(21) However, when it is necessary to form a more complicated temperature profile, a device using not only one zone but using a plurality of vapor heating furnaces or a plurality of heating furnaces that use heating means other than a heating method, in which latent heat of condensation of vapor is used, is necessary. In this case, in a narrow space between the plurality of adjacent vapor heating furnace or between the plurality of heating furnaces, a special mechanism for preventing vapor from flowing out is necessary. Therefore, a full length of a continuous furnace is long.
(22) Hereinafter, an exemplary embodiment of the present disclosure will be described with reference to the drawings.
EXEMPLARY EMBODIMENT
(23)
(24) Gas phase type heating device 50 is configured, for example, by serially connecting a plurality of heating furnaces 5. Gas phase type heating device 50 includes at least one vapor heating furnace 4 that heats object 1 by being given with latent heat of condensation of vapor 3 of heat transfer liquid 2. In a case of
(25) Vapor heating furnace 4 has, in the vicinity of a bottom surface, tub 4x that holds a predetermined amount of heat transfer liquid 2. In tub 4x, heating source 17 such as an electric heater for heating heat transfer liquid 2 to turn into vapor 3 is included.
(26) Heating source 17 may adopt an immersion type configuration where a heating source is immersed and used in tub 4x of heat transfer liquid 2. Alternatively, heating source 17 may adopt a configuration of heating an entire wall surface of tub 4x or a part of the wall surface of tub 4x. Heating source 17 requires a heating performance that is at least necessary to turn a larger amount of heat transfer liquid 2 into vapor 3 than the amount of vapor 3 of heat transfer liquid 2 that is cooled and liquefied by an inner wall surface of vapor heating furnace 4, cooler 8, or transporter 9. In addition, heating source 17 requires a heating performance greater than a total heating performance that is applied to heat transfer liquid 2 to form a necessary amount of vapor 3 to heat object 1 at a desired temperature rising speed. Transporter 9 is formed of, for example, a belt conveyor that penetrates the continuous furnace and can transport object 1.
(27) The wall surface of vapor heating furnace 4 has at least two communicating portions (first communicating portion 6 and second communicating portion 7) for communicating with heating furnaces 5 disposed on an upstream side or a downstream side of the vapor heating furnace. First communicating portion 6 is an opening portion necessary for loading object 1 into vapor heating furnace 4 from upstream heating furnaces 5 or unloading object 1 from vapor heating furnace 4 to downstream heating furnaces 5. That is, first communicating portion 6 functions as, for example, a loading/unloading portion for allowing transporter 9 for loading and unloading object 1 to cause object 1 to pass through. Second communicating portion 7 is formed above first communicating portion 6 for loading and unloading object 1, in vapor heating furnace 4. Second communicating portion 7 communicates with each of heating furnaces 5 disposed on the upstream side and the downstream side of vapor heating furnace 4. In
(28) A cooling device that cools a surface of a pipe disposed along the inner wall surface of vapor heating furnace 4 by causing water cooled in an external space of vapor heating furnace 4 to flow into the pipe can be exemplified as cooler 8.
(29) Herein, steps of a gas phase type heating method will be described.
(30) First, before loading object 1 into gas phase type heating device 50, which is the continuous furnace, a vapor phase of vapor 3 is formed and increased in vapor heating furnace 4 by heating heat transfer liquid 2 in tub 4x with heating source 17 and giving latent heat of gasification for continuously turning heat transfer liquid 2 into vapor 3, as preparation for heating. At an early state of operation of heating source 17, a temperature of each part in vapor heating furnace 4 is equal to or lower than a boiling point of heat transfer liquid 2. Therefore, vapor 3 of heat transfer liquid 2, which is in contact with each part in vapor heating furnace 4, gives latent heat of condensation to each part in contact with the vapor and is liquefied. Then, liquefied heat transfer liquid 2 falls to a lower portion of vapor heating furnace 4 due to its own weight, and is collected by tub 4x of heat transfer liquid 2. By repeating this, each part in vapor heating furnace 4 is gradually heated by receiving the latent heat of condensation of heat transfer liquid 2, and subsequently reaches a boiling temperature of heat transfer liquid 2.
(31) Consequently, a boundary surface between an atmospheric phase in vapor heating furnace 4 and a vapor phase of vapor 3 of heat transfer liquid 2 moves gradually upwards, and reaches cooler 8. Cooler 8 adjusts a temperature with water so as to be a constant temperature for the purpose of cooling vapor 3 of heat transfer liquid 2, which is in contact with the cooler, and thereby liquefying and collecting the vapor. This water is introduced into the pipe from outside vapor heating furnace 4. Therefore, the water brings latent heat of condensation generated by contacting with vapor 3 of heat transfer liquid 2 out to the external space of vapor heating furnace 4, and thus a temperature of a surface of the pipe does not reach the boiling point of heat transfer liquid 2. Consequently, the boundary surface between the atmospheric phase in vapor heating furnace 4 and the vapor phase of vapor 3 of heat transfer liquid 2 reaches a height of cooler 8 and is held in the vicinity of the wall surface of vapor heating furnace 4. Since the specific gravity of vapor 3 of heat transfer liquid 2 is greater than the specific gravity of the atmosphere, as vapor 3 in the vicinity of the wall surface is liquefied, also vapor 3 in the vicinity of a center of vapor heating furnace 4 moves toward the wall surface and is cooled by cooler 8. That is, since vapor 3 of heat transfer liquid 2 is unlikely to reach a space above cooler 8, the space above cooler 8 becomes space 51 where only a saturated vapor pressure component of vapor 3 of heat transfer liquid 2 at a temperature of the space can exist and there is an extremely small amount of vapor 3 of heat transfer liquid 2 compared to a vapor phase below cooler 8.
(32) An inlet shape of first communicating portion 6, which is an opening for transporter 9 for object 1, or a shape inside the communicating portion, has a structure with a large inlet loss or a large pressure loss such that vapor 3 of heat transfer liquid 2 is unlikely to flow to adjacent heating furnace 5 communicating with the upstream side or the downstream side. In addition, an inlet shape of second communicating portion 7 above cooler 8 or a shape inside the communicating portion has a structure with a small inlet loss or a small pressure loss such that a gas with a small amount of vapor 3 of heat transfer liquid 2, which exists in the space above cooler 8, is likely to flow.
(33) Due to such a configuration, heat transfer liquid 2 is heated in vapor heating furnace 4, and a pressure difference between vapor heating furnace 4 and heating furnaces 5 in front and back of the vapor heating furnace occurs due to a pressure rise in vapor heating furnace 4 caused by volume expansion with a phase change from a liquid to a gas, which is becoming vapor 3. However, in the configuration, exchange of a gas between vapor heating furnace 4 and heating furnaces 5 in front and back of the vapor heating furnace is performed preferentially through second communicating portion 7 over first communicating portion 6. That is because second communicating portion 7 is disposed in space 51 which is above cooler 8 and in which a gas with a small amount of vapor 3 of heat transfer liquid 2 exists. Consequently, the pressure difference is eliminated. At this time, vapor 3 of heat transfer liquid 2 is unlikely to flow into first communicating portion 6 which is on transporter 9 for object 1 below cooler 8 and has a structure with a large inlet loss. Consequently, vapor 3 of heat transfer liquid 2 is prevented from flowing out from vapor heating furnace 4 to adjacent heating furnaces 5 in front and back of the vapor heating furnace.
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(35) Another heat transfer liquid 2A having a boiling point different from a boiling point of heat transfer liquid 2 in vapor heating furnace 4 is used in upstream vapor heating furnace 4A in some cases. Instead, as another example, specifications of heat transfer liquid 2 in vapor heating furnace 4 and specifications of heat transfer liquid 2A are the same, and the amount of heat energy given to heat transfer liquid 2A is controlled. Accordingly, vapor heating furnace 4A, in which a concentration of vapor 3A of heat transfer liquid 2A is made different from a concentration of vapor 3 of heat transfer liquid 2 in vapor heating furnace 4, may be used.
(36) Characteristics related to configurations of the communicating portions between vapor heating furnace 4 and vapor heating furnace 4A (first communicating portion 6 and second communicating portion 7) may be the same as in the case of
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(38) As for a pressure change between first vapor heating furnace 4a and second vapor heating furnace 4b, a pressure difference between first vapor heating furnace 4a or second vapor heating furnace 4b and heating furnace 5 that communicates with first vapor heating furnace 4a or second vapor heating furnace 4b on the upstream side or the downstream side thereof can be eliminated by the configuration of
(39) As illustrated in
(40) Hereinafter, a specific operation of inlet chamber 15 will be described.
(41) First, in
(42) Herein, a pressure adjusting operation is performed in the state of
(43) After this pressure adjustment is completed, outlet side shutter 12A is opened with inlet side shutter 11A of inlet chamber 15 closed, and object 1 is delivered and loaded into first vapor heating furnace 4a as in
(44) After loading object 1, outlet side shutter 12A is closed, and inlet chamber 15 and first vapor heating furnace 4a are shielded as in
(45) After then, object 1 reaches cooler 19 from first vapor heating furnace 4a via heating furnace 5 and second vapor heating furnace 4b.
(46) On the other hand, when unloading object 1 from cooler 19 which is a downstream end portion of the continuous furnace, inlet side shutter 11B, which is on the upstream side of outlet chamber 16, and outlet side shutter 12B come into a closed state. The atmosphere outside the furnace is introduced by pressure adjuster 14B such that a pressure difference is reduced based on a result of detection of a pressure in cooler 19 by pressure detector 13B. Accordingly, pressure adjuster 14B adjusts a pressure in outlet chamber 16 such that the pressure becomes the same as the pressure in cooler 19.
(47) After this pressure adjustment is completed, inlet side shutter 11B is opened with outlet side shutter 12B closed, and object 1 is loaded into outlet chamber 16 from cooler 19.
(48) After the object is completely loaded, inlet side shutter 11B is closed. After then, outlet side shutter 12B is opened, and object 1 is delivered and unloaded to the outside of the continuous furnace.
(49) Accordingly, when loading object 1 into the continuous furnace, and when unloading the object to the outside of the continuous furnace, it is possible to avoid vapor 3 of heat transfer liquid 2 in the continuous furnace flowing outside the continuous furnace without depending on a pressure in the continuous furnace.
(50) It is also possible to make pressure adjustment in inlet chamber 15 and outlet chamber 16 unnecessary by maintaining a pressure change amount caused by volume expansion as a result of gasification of heat transfer liquid 2 in first vapor heating furnace 4a and second vapor heating furnace 4b at the atmospheric pressure.
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(53) Therefore, a heating step can be made longer or shorter than in the temperature profile of the case of
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(55) In
(56) In
(57) Communicating portion 60C of
(58) In
(59) In
(60) Making an upstream inlet shape (inlet shape) and a downstream inlet shape (inlet shape) of first communicating portion 6 the same allows easy control since inlet losses can be made the same. Similarly, making an upstream inlet shape (inlet shape) and a downstream inlet shape (inlet shape) of second communicating portion 7 the same allows easy control since inlet losses can be made the same.
(61) Ease of flow of air flow to opening portion 63 can be determined by an inlet loss. Therefore, by defining the inlet shapes of first communicating portion 6 and second communicating portion 7, a difference is made between an inlet loss of first communicating portion 6 and an inlet loss of second communicating portion 7, and the inlet loss of second communicating portion 7 can be made smaller than the inlet loss of first communicating portion 6. Accordingly, the exchange of air flow between furnace bodies adjacent to second communicating portion 7 can be preferentially performed over first communicating portion 6. Inlet loss ΔP is determined from a loss factor and a density and a flow speed of a fluid, and the following equation is acquired.
Inlet loss ΔP=Loss factor×Density×(Flow speed).sup.2/2
(62) A configuration where a difference in an inlet loss is made between first communicating portion 6 and second communicating portion 7, which shows ease of flow of air flow to opening portion 63, and the inlet loss of second communicating portion 7 is made small is described as follows. For example, second communicating portion 7 has a configuration of having an inlet-side opening surrounded by a surface that is inclined or curved with respect to an axial direction of the second communicating portion (long-axis direction). First communicating portion 6 has a configuration of having an inlet-side opening surrounded by a surface orthogonal to the axial direction (long-axis direction). Due to this configuration, a pressure loss of second communicating portion 7 can be made smaller than a pressure loss of first communicating portion 6.
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(64) Herein, the equation of an inlet loss is applied in a configuration of
(65) First, as for a density, in a case of vapor heating furnace 4 of
(66) Accordingly, a value of an inlet loss depends significantly on the size of a loss factor in the equation herein, since a shape in
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(68) In
(69) A pressure difference between vapor heating furnace 4 and heating furnace 5 adjacent to each other in second communicating portion 7 with a small pressure loss in space 51 where there is a small amount of vapor 3 can be eliminated through the configuration. Consequently, the movement of vapor 3 in first communicating portion 6, which has a large amount of vapor 3 and is the loading/unloading portion for object 1, can be reduced. Accordingly, it is possible to reduce the movement and flowing-out of vapor 3 in vapor heating furnace 4.
(70) That is, even when a furnace, in which vapor heating furnace 4 and heating furnace 5 are connected to each other at a narrow interval, is adopted in the exemplary embodiment, a special mechanism for preventing vapor from flowing out is unnecessary in second communicating portion 7 between vapor heating furnace 4 (or vapor heating furnace 4A, first vapor heating furnace 4a, and second vapor heating furnace 4b) that heats object 1 by using latent heat of condensation of vapor 3 of heat transfer liquid 2 and adjacent heating furnace 5. Thus, a pressure difference between vapor heating furnaces 4 and 4A, first vapor heating furnace 4a, or second vapor heating furnace 4b and heating furnace 5 can be reduced in second communicating portion 7 with a small pressure loss in space 51 where there is a small amount of vapor 3. Consequently, the movement of vapor 3 in first communicating portion 6, which has a large amount of vapor 3 and is a transporting surface for object 1, can be reduced. Accordingly, a vapor concentration of heat transfer liquid 2 in vapor heating furnace 4 and a heating performance according to latent heat of condensation can be stably controlled by vapor heating furnace 4.
(71) The present disclosure is not limited to the exemplary embodiment, and can be executed through other various aspects. For example, although heating source 17 is disposed in tub 4x which is in the lower portion inside vapor heating furnace 4, the present disclosure is not limited to this configuration. For example, as illustrated in
(72) By appropriately combining any examples out of the various examples, effects of each example can be achieved. In addition, it is possible to combine the examples, and it is also possible to combine characteristics of the different examples.
(73) As described above, in the gas phase type heating method and the gas phase type heating device of the present disclosure, a vapor heating furnace that heats an object by using latent heat of condensation of vapor of a heat transfer liquid and a special mechanism for preventing vapor from flowing out are unnecessary even when a furnace in which a plurality of heating furnaces are connected to each other at a narrow interval is adopted.
(74) Therefore, a pressure difference between the heating furnaces adjacent to each other in a communicating portion with a small pressure loss in a region where there is a small amount of vapor can be reduced. Consequently, the movement of vapor in the communicating portion, which has a large amount of vapor and is a transporting surface for the object, can be reduced. Accordingly, a vapor concentration of the heat transfer liquid in the vapor heating furnace and a heating performance according to latent heat of condensation can be stably controlled by the vapor heating furnace.
(75) The gas phase type heating method and the gas phase type heating device according to an aspect of the present disclosure can increase and decrease a concentration of vapor of a heat transfer liquid that transfers heat to an object to adjust the concentration and to make concentration uniform and can increase and decrease a temperature rising speed. In addition, when heating the object, a difference in a heating performance does not occur according to a place and time, and it is possible to heat an object with a three-dimensional shape through uniform heat transfer. Therefore, as a heating method and a heating device that uniformly heats a three-dimensional object, the aspect of the present disclosure can be applied to a heating processing method and a heating processing device that performs various types of heating processing by a drying furnace, a curing furnace, or a reflow furnace in an industrial product or home appliances manufacturing step or a various types of electronic components manufacturing step.