JP4841567B2 - Latent heat exchanger - Google Patents

Description

  The present invention relates to a latent heat exchanger that recovers latent heat from combustion exhaust via an endothermic tube.

  FIG. 4 shows that the sensible heat recovery type sensible heat exchanger (11) and the latent heat recovery type latent heat exchanger (12) are provided in the instrument body (1), and the sensible heat exchanger (11). FIG. 5 is a vertical cross-sectional view of a so-called condensing type water heater in which latent heat is absorbed by the latent heat exchanger (12) after the sensible heat of the combustion exhaust is absorbed by FIG. It is a cross-sectional view of 12).

In this device, as shown in FIG. 4, a sensible heat exchanger (11) is provided below the latent heat exchanger (12), and further below the sensible heat exchanger (11), a gas is provided. A gas burner (19) for burning the gas supplied from the supply pipe (13) is provided. The sensible heat exchanger (11), the latent heat exchanger (12), and the gas burner (19) are accommodated in casings (31), (32), and (33), respectively.
Below the lower casing (33), there is provided a blower fan (14) for supplying air sucked from the outside to the gas burner (19) as combustion air.

The sensible heat exchanger (11) and the latent heat exchanger (12) are partitioned vertically by a drain receiving plate (21) positioned below the latent heat exchanger (12). Above (21), an exhaust guide plate (22) covering the upper part of the latent heat exchanger (12) is disposed.
The drain receiving plate (21) and the exhaust guide plate (22) are both inclined plates that descend toward the exhaust port (3), and the latent heat exchanger (12) is disposed in the upper casing (32). The drain receiving plate (21) and the exhaust guide plate (22) are surrounded by the side plates surrounding the four sides.

  The sensible heat exchanger (11) and the latent heat exchanger (12) communicate with each other through the exhaust inlet (10) on the rising end side of the drain receiving plate (21), and the sensible heat exchanger (11 The combustion exhaust gas sent into the latent heat exchanger (12) from the exhaust inlet (10) through the exhaust inlet (10) descends along the exhaust guide plate (22) after passing through the latent heat exchanger (12). At the same time, the gas is discharged from the exhaust port (3) to the outside of the instrument body (1).

In this type of water heater, combustion exhaust is generated by combustion of the gas burner (19), the sensible heat exchanger (11) and the latent heat exchanger (12) are heated by this combustion exhaust, and the sensible heat exchanger ( The sensible heat of the combustion exhaust is absorbed by 11), and the latent heat is absorbed from the combustion exhaust after the sensible heat is absorbed by the latent heat exchanger (12). At this time, the water vapor in the combustion exhaust gas is cooled below the dew point and the contained water vapor is condensed, so that drain is generated in the latent heat exchanger (12). Drain generated in the latent heat exchanger (12) is dropped on the drain receiving plate (21), and from the drain discharge pipe (24) on the descending end side of the drain receiving plate (21), a drain collecting device (34), neutralized in the drain recovery device (34), and then discharged to the outside.
The sensible heat exchanger (11) is provided with a copper endothermic tube (11a), and the latent heat exchanger (12) has an endothermic tube (12a) made of corrosion-resistant titanium or stainless steel. It is arranged.

  As shown in FIG. 5, the upstream end of the heat absorption pipe (12a) guides cold water from a water supply source such as a water pipe through an inflow header (2) attached to a side plate (35) on one side. It is connected to the water supply pipe (17), and the downstream end is connected to the sensible heat exchanger (20) through the outflow header (20) attached to the side plate (35) in parallel with the inflow header (2). A connecting pipe (18) communicating with the upstream end of the endothermic pipe (11a) of 11) is connected. The cold water from the water supply pipe (17) is heated by the latent heat exchanger (12) and the sensible heat exchanger (11) while passing through the heat absorption pipe (12a) and the heat absorption pipe (11a) to become hot water, From the hot water outlet pipe (30) to which the downstream end of the endothermic pipe (11a) is connected, it is sent to a currant or the like in a bathroom or kitchen.

  As shown in FIG. 6, each of the inflow header (2) and the outflow header (20) is composed of a header body (4) and a header lid (5). The header body (4) includes a heat absorption pipe. Insertion holes (40) at the upstream end or the downstream end of (12a) are provided in the number corresponding to the number of heat absorption pipes (12a). A joint cylinder (50) for connecting (18) is provided so as to penetrate therethrough.

  Also, the peripheral edge of the bottom plate (41) in which the insertion hole (40) of the header body (4) is formed, and the lid main body from which the joint cylinder (50) of the header lid (5) protrudes ( The peripheral wall (42) (52) extending in the same direction is provided from the periphery of 51), and the peripheral wall (52) of the header lid (5) is fitted inside the peripheral wall (42) of the header body (4). The inflow header (2) and the outflow header (20) are completed by brazing and brazing.

Mounting flanges (43) and (43) project from predetermined positions opposite to each other at the open ends of the peripheral wall (42) of the header body (4), and the mounting flanges (43) and (43) are connected to the side plate. It is attached to the inner surface of (35) with screws. The mounting flanges (43) and (43) may be fixed to the side plate (35) by brazing.
Accordingly, as shown in FIG. 5, the inflow header (2) and the outflow header (20) are formed on the inner surface of the side plate (35) on one side of the upper casing (32) in which the latent heat exchanger (12) is accommodated. ) Is attached.
JP 2007-163096 A JP 2005-283040 A

  However, in the inflow header (2) and the outflow header (20) having the above-described conventional configuration, the upstream end or the downstream end of the heat absorption pipe (12a) is inserted into the insertion hole (40) of the header body (4) and brazed. At the same time, the header lid (5) is fitted into the header body (4) and brazed, and the mounting flange (43) (43) of the header body (4) is attached to the side plate (35) of the upper casing (32). A process such as screwing or brazing is required, and the number of parts is large, and there are many brazing points, and the assembling work is troublesome. Also, in the inflow header (2) and the outflow header (20) attached to the side plate (35) with the mounting flanges (43) and (43), from the water supply pipe (17) to the upstream end of the heat absorption pipe (12a). A large water pressure is applied by a water hammer at the time of entering the water, at the time of hot water after passing through the heat absorption pipe (12a), or at the time of stopping hot water. These hydraulic pressures act as a force in the direction of separating the header body (4) from the side plate (35) or the header lid (5), so that the header body (4) is detached from the header lid (5) or the side plate ( 35), the water could leak from the inflow header (2) or the outflow header (20).

According to the present invention, an inflow header and an outflow header are provided on a side plate of a casing in which a plurality of endothermic tubes through which a fluid to be heated flows are arranged in a meandering state. And
Each of the inflow header and the outflow header has a plurality of insertion holes into which the end portions of the heat absorption tubes are inserted, and closes the opening portion of the header body, which is open toward one side. With a header lid that
A latent heat heat exchanger in which a water supply pipe is connected to the header lid constituting the inflow header, and a connection pipe to a sensible heat exchanger is connected to the header lid constituting the outflow header. In this case, the number of parts is reduced and the number of brazing points is reduced, thereby simplifying the manufacturing process. Even if water pressure is applied to the inflow header or the outflow header when the water hammer is applied, the brazing between the header body and the header lid is performed. It is an object of the present invention to prevent inconveniences in which the attaching portion is damaged or the header body is dropped from the side plate.

(1) The latent heat exchanger of the invention according to claim 1 is: "The header body is formed integrally with the side plate by indenting a predetermined portion of the side plate of the casing inward ,
The header lid is composed of a lid main body that closes an open end of the header body, and a peripheral wall that extends from the periphery of the lid body toward the other side and fits inside the header body,
The outer surface of the peripheral wall of the header lid is joined to the inner peripheral wall of the header body by brazing ”.
The technical means operates as follows.
The side plate of the casing is drawn to form a recess that opens to one side, which is used as a header body. Thereby, a header main body turns into the aspect integrally provided in the said side plate. The header lid is provided with a peripheral wall that opens in the direction opposite to the opening direction of the header body (the other side) from the periphery of the lid main body that closes the open end of the recess as the header body. When the open end of the header main body is closed with the lid main body, the peripheral wall is fitted into the header main body, and assembly of the latent heat exchanger connection is performed by brazing the peripheral wall to the inner peripheral wall of the header main body. Is completed.

  The water pressure is applied to the inflow header and the outflow header at the time of entering water into which the water from the water supply pipe flows into the inflow header, the hot water from which the hot water from the heat absorption pipe flows into the outflow header, and the stop of the hot water The header body acts as a force in the direction of separating the header body and the header lid, and at the same time, the water pressure also acts as a force in the direction of pressing the peripheral wall of the header lid against the inner peripheral wall of the header body. The bonding strength of the outer peripheral surface of the header lid with respect to the inner peripheral wall is increased.

Moreover, the said header main body becomes a recessed part open | released toward the outer side of a casing, and the surrounding wall of a header lid is internally fitted and brazed from the outer side open part. Should the heated fluid leak from this brazed portion, the heated fluid will leak to the outside of the casing.

(2) Claim 2 is as described in claim 1, wherein the insertion hole of the header body is formed by burring, and each end of the heat absorption tube is inserted into the burring part and brazed. In this case, a rising portion is formed in the burring portion at the periphery of the insertion hole of the header body, and each endothermic tube is formed on the inner peripheral surface of the rising portion. It brazes in the state which the outer peripheral surface of the edge part contacted. In the case where the insertion hole is provided by simply punching, the outer peripheral surface of the heat absorption tube is in contact with only the portion corresponding to the thickness of the header body, so that compared to this case, the heat absorption tube and the insertion hole The contact area can be set larger by the inner peripheral area of the rising portion, and the welding area is increased accordingly.

As described above, according to the first aspect of the present invention, since the header body is integrally provided on the side plate by partially indenting the side plate of the casing, the header body is separately provided. The number of parts can be reduced as compared with the conventional one prepared. Since the attachment work for attaching the header body to the side plate is unnecessary, the assembly process of providing the inflow header and the outflow header on the casing can be simplified. In addition, since the water pressure applied to the inflow header and the outflow header at the time of the water hammer also acts as a force in the direction in which the peripheral wall of the header lid presses the inner peripheral surface of the header body, the header cover is joined to the header body by the water pressure. Strength increases. Therefore, it is possible to prevent the inconvenience that the header lid is dropped from the header body.

In addition, when the fluid to be heated leaks, the fluid to be heated leaks out of the casing, so that it is easy to find the leak and can respond quickly. Further, since repair such as brazing can be performed from the outside of the casing, the repair work can be easily performed.

According to the second aspect , since the contact area between the heat absorption pipe and the insertion hole is set large and the welding area such as brazing is increased accordingly, the bonding strength of the heat absorption pipe to the inflow header or outflow header is increased. , Durability is improved.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings.
The latent heat exchanger according to the embodiment of the present invention can be adopted in a condensing type latent heat recovery type water heater similar to the conventional one shown in FIG. 4, and a gas burner ( 19), a lower casing (33) that is a combustion section, a middle casing (31) that is connected to the upper casing and houses the sensible heat exchanger (11), and a further upper casing The upper casing (32) is connected and accommodates the latent heat exchanger (12).

The lower casing (33) and the middle casing (31) can have the same configuration as the conventional one, and only the configuration of the upper casing (32) will be described below.
The upper casing (32) is covered with an exhaust guide plate (22) at the top, a drain pan (21) is disposed between the upper casing (31) and the lower middle casing (31), and is surrounded by side walls on all sides. The exhaust guide plate (22) and the drain receiving plate (21) are each configured to descend toward the front wall (16a) of the upper casing (32).

  The upper casing (32) and the middle casing (31) communicate with each other via an exhaust inlet (10) provided in the drain tray (21) along the rear wall (16b) of the upper casing (32). In addition, the exhaust port (3) is open in the upper region of the front wall (16a).

  In the latent heat exchanger (12), a plurality of endothermic pipes (12a) each made of titanium or stainless steel pipes are arranged in a meandering state, and an upstream end (121) and a downstream end ( 122) are connected together to an inflow header (2) and an outflow header (20) respectively disposed on a side plate (35) on one side of the upper casing (32), as shown in FIG. ing.

  A water supply pipe (17) for guiding cold water from a water supply source such as a water pipe is connected to the inflow header (2), and a sensible heat exchanger in the inner casing (31) is connected to the outflow header (20). A connection pipe (18) communicating with the upstream end of the heat absorption pipe (11a) of (11) is connected, and cold water from the water supply pipe (17) passes through the heat absorption pipe (12a) and the heat absorption pipe (11a). In the meantime, the temperature is raised by the latent heat exchanger (12) and the sensible heat exchanger (11), and the hot water is discharged to a hot water pipe connected to a bathroom, a washroom, and a kitchen curan.

  As shown in FIGS. 1, 2, and 3, the formation regions of the inflow header (2) and the outflow header (20) in the side plate (35) are drawn at predetermined positions of the side plate (35), respectively. Thus, a recess (53) is formed by being recessed inward, and this recess (53) functions as the header body (4).

  The bottom plate (41) of the recess (53) is subjected to burring as many as the number of the heat absorption pipes (12a), so that the rising portion protruding from the bottom plate (41) to the inside of the upper casing (32) ( An insertion hole (40) (40) having a peripheral edge 44) is formed.

  The header lid (5) for closing the open end of the header body (4) includes a lid main body (51) for closing the outward open end of the recess (53) constituting the header body (4), and a lid. It is formed in a rectangular shallow vessel shape from a peripheral wall (52) extending in a direction substantially perpendicular to the lid main body (51) from the peripheral edge of the main body (51), and the peripheral wall (52) is formed in the recess (53). It is set to a size that fits closely into the inner peripheral wall. Further, an opening (54) is formed near the lower end of the lid main body (51) by burring, and the water supply pipe (17) or the sensible heat exchanger (11) is formed in the opening (54). The joint tube (50) is connected to connect the upstream end connection pipe (18) of the heat absorption pipe (11a).

  In the latent heat exchanger of this embodiment, first, as shown in FIG. 3, the heat absorption tubes are respectively inserted into the insertion holes (40) (40) of the recesses (53) provided integrally with the side plate (35). The upstream end (121) or the downstream end (122) of (12a) is inserted from the inside of the side plate (35). At this time, the inner peripheral surface of the rising portion (44) (44) of the insertion hole (40) (40) comes into contact with the outer peripheral surface of the upstream end (121) or the downstream end (122). Weld the parts by brazing.

  Further, by inserting the peripheral wall (52) of the header lid (5) from the outer open end of the recess (53), the outer open end is closed by the lid main body (51). Then, the peripheral wall (52) of the header lid (5) is joined to the inner peripheral surface of the recess (53) by brazing. Then, the insertion tube portion (55) of the joint tube (50) is inserted into the opening (54) provided in the lid main body (51) and brazed.

  As a result, the heat absorption pipe (12a), the header lid (5), and the joint cylinder (50) are integrally joined to the side plate (35), and the heat absorption pipe (12a) is accommodated in the upper casing (32). As described above, the side plate (35) closes the one side opening of the upper casing (32), thereby completing the assembly of the latent heat exchanger (12).

  In the case of the latent heat recovery type water heater of this embodiment, during hot water supply, cold water whose water flow is detected by a water amount sensor (not shown) flows to the water supply pipe (17) and absorbs heat through the inflow header (2). At the same time as it flows into the pipe (12a), the blower fan (14) shown in FIG. 4 is activated, and combustion air is sent to the gas burner (19). As a result, the gas burner (19) is burned, and the combustion exhaust is discharged. Generated. The sensible heat exchanger (11) and the latent heat exchanger (12) are heated by the combustion exhaust.

  The combustion exhaust gas has its sensible heat absorbed by the sensible heat exchanger (11) in the middle casing (31), and the latent heat heat exchanger (12 in the upper casing (32) through the exhaust inlet (10). ) And the latent heat is further absorbed by the latent heat exchanger (12). In this way, the combustion exhaust gas gives its sensible heat, and further latent heat, to the sensible heat exchanger (11) and the latent heat exchanger (12), thereby absorbing the heat in the sensible heat exchanger (11). The pipe (11a) and the heat absorption pipe (12a) in the latent heat exchanger (12) are heated, the downstream end (122) of the heat absorption pipe (12a), the outflow header (20), and the connection pipe (18) Then, it is sent to the heat absorption pipe (11a) to become hot water, and hot water is discharged from the hot water tap.

Further, the combustion exhaust gas sent to the latent heat exchanger (12) is exhausted from the exhaust port (3) opened to the upper region of the front wall (16a) of the upper casing (32).
When tap water flows from the water supply pipe (17) into the inflow header (2), or when hot water flows from the downstream end (122) of the heat absorption pipe (12a) into the outflow header (20), the tap water is stopped. Water pressure is applied to the inflow header (2) and the outflow header (20), respectively. This water pressure acts as a force in the direction of separating the header lid (5) from the recess (53), and as shown by the arrow in FIG. 3, the peripheral wall (52) of the header lid (5) This also acts as a force in the direction of pressing against the inner peripheral surface of the. As a result, the bonding strength of the header lid (5) to the recess (53) (header body (4)) is increased, and the durability of the inflow header (2) and the outflow header (20) during a water hammer is improved.

  Should water leak from the brazed part of the peripheral wall (52) of the header lid (5) to the inner peripheral surface of the recess (53), the water leaks to the outside of the upper casing (32). It will leak. Therefore, early detection of water leakage is possible, and repair can be performed from the outside of the upper casing (32), so that repair and maintenance work can be easily performed.

  The insertion hole (40) provided in the header body (4) connecting the upstream end (121) and the downstream end (122) of the heat absorption pipe (12a) rises from the peripheral edge of the insertion hole (40) by burring. Since the portion (44) has a shape protruding, the upstream end (121) and the downstream end (122) are inserted into the rising portion (44) and brazed to the entire inner peripheral surface of the rising portion (44). can do. In this way, the upstream end (121) and the downstream end (122) are compared with the structure in which the insertion hole is formed by simply punching the bottom plate (41) (the welding area is only the thickness of the bottom plate (41)). ) To the insertion hole (40) can be set large, so that the durability of the latent heat exchanger (12) is improved.

  Furthermore, since the header body (4) is formed as a recess (53) provided in the side plate (35), the header body (4) is provided integrally with the side plate (35), so compared to the conventional one. The number of parts is reduced, and accordingly, brazing points or fastening points can be reduced, and the assembling work can be simplified.

The cross-sectional view of the latent heat exchanger according to the embodiment of the present invention. The disassembled perspective view which shows the header main body and header lid which comprise the inflow header provided in the casing of the latent heat exchanger of embodiment of this invention, or an outflow header. The expanded longitudinal cross-sectional view of the inflow header or outflow header provided in the casing of the latent heat exchanger of embodiment of this invention. The schematic longitudinal cross-sectional view of the conventional latent heat recovery type water heater. The cross-sectional view of the conventional latent heat exchanger. The disassembled perspective view which shows the header main body and header lid which were employ | adopted as the conventional latent heat exchanger.

Explanation of symbols

(12a) ...
(121) ・ ・ ・ ・ ・ ・ ・ Upstream end
(122) ・ ・ ・ ・ ・ ・ ・ Downstream end
(17) ... Water supply pipe
(18) ... Connection pipe
(2) ... Inflow header
(20) ... Outflow header
(32) ... Case
(35) ・ ・ ・ ・ ・ ・ ・ ・ Side plate
(4) ... Header body
(40) ... Insertion hole
(5) .... header lid

Claims (2)

An inflow header and an outflow header to which the upstream end and the downstream end of the heat absorption tube are respectively connected are provided on the side plate of the casing in which a plurality of heat absorption tubes through which the fluid to be heated flows are arranged in a meandering state,
Each of the inflow header and the outflow header has a plurality of insertion holes into which the end portions of the heat absorption tubes are inserted, and closes the opening portion of the header body, which is open toward one side. With a header lid that
In the latent heat heat exchanger, a water supply pipe is connected to the header lid constituting the inflow header, and a connection pipe to a sensible heat exchanger is connected to the header lid constituting the outflow header. ,
The header body is formed integrally with the side plate by indenting a predetermined portion of the side plate of the casing inward .
The header lid is composed of a lid main body that closes an open end of the header body, and a peripheral wall that extends from the periphery of the lid body toward the other side and fits inside the header body,
A latent heat heat exchanger, wherein the outer peripheral surface of the header lid is joined to the inner peripheral wall of the header body by brazing. 2. The latent heat exchanger according to claim 1, wherein the insertion hole of the header body is formed by burring, and each end of the heat absorption tube is inserted into the burring portion and connected by brazing. A latent heat exchanger characterized by that.

Images