Ventilation device
The ventilation device addresses condensation issues by using a water tray with differential heat transfer coefficients and a foamed resin material, enhancing insulation and ventilation efficiency while reducing manufacturing costs.
Patent Information
- Application Number
- JP2024030271
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-02-29
- Publication Date
- 2025-09-10
AI Technical Summary
Existing ventilation devices installed on ceilings face issues with condensation on the bottom wall of the casing due to the uniform thickness of the water tray, which fails to ensure adequate insulation, leading to cooling of stored water and the casing.
A ventilation device with a water receiving tray attached to the casing wall, featuring an outdoor water storage section with a lower heat transfer coefficient than the indoor section, and a foamed resin material to reduce heat transmission, along with a water channel connecting both sections to prevent overflow and maintain ventilation efficiency.
The configuration suppresses condensation on the casing bottom wall, improves insulation, reduces manufacturing costs, and maintains effective ventilation rates by minimizing heat transfer and water overflow.
Smart Images
Figure 2025132599000001_ABST
Abstract
Description
[Technical Field]
[0001] The present disclosure relates to ventilation devices. [Background technology]
[0002] Conventionally, an indoor unit of an air conditioner is known (see, for example, Patent Document 1). This indoor unit is provided with a drain pan that is disposed inside the casing above the bottom plate of the casing and that receives drain water generated in a heat exchanger provided inside the casing.
[0003] Also known is a ventilation device that exchanges air between indoors and outdoors (see, for example, Patent Document 2). This ventilation device has a box-shaped casing formed in a rectangular parallelepiped shape, and the casing houses a total heat exchanger, an intake fan, and an exhaust fan. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] Japanese Patent Publication No. 2020-085403 [Patent Document 2] Japanese Patent Publication No. 2022-75246 Summary of the Invention [Problem to be solved by the invention]
[0005] When the ventilation device described in the aforementioned Patent Document 2 is installed on the ceiling, a water tray is placed across the indoor and outdoor areas separated by the total heat exchanger in the casing to collect water droplets dripping from the total heat exchanger. In such a ventilation device, the thickness of the bottom wall of the water tray is determined to ensure the required amount of water storage in the water tray, taking into account the height restrictions of the casing and the total heat exchanger.
[0006] Therefore, unlike the drain pan of the indoor unit described in the aforementioned Patent Document 1, the bottom wall of the ventilation system's water tray has a uniform thickness and is in contact with the upper surface of the bottom wall of the casing. In such a case, the necessary insulating performance cannot be ensured for the bottom wall of the water tray, and the water stored in the water tray and the air passing over the water tray may cool the bottom wall of the casing, causing condensation.
[0007] The present disclosure provides a ventilation device that can suppress condensation on the bottom wall of a casing. [Means for solving the problem]
[0008] One aspect of the present disclosure is a system for controlling a temperature change of an air conditioner, the system comprising: a main casing (1); a total heat exchanger (4) installed in the middle of an air supply passage (16) and an exhaust passage (15) inside the main casing (1); and a water receiving tray (6) attached to a wall surface (1ei) of the main casing (1) for collecting water dripping from the total heat exchanger (4). The water receiving tray (6) is attached to a wall surface (1ei) of the main casing (1) of the air supply passage (16) connected to an air supply inlet (13) on an outdoor end surface (1b) of the main casing (1). The ventilation device (HRV) has an outdoor water storage section (61) arranged in the intake air upstream section (16a) and an indoor water storage section (62) arranged in the exhaust upstream section (15a) of the exhaust passage (15) connected to an exhaust inlet (11) on the indoor end face (1a) of the main body casing (1), and the heat transfer coefficient of the outdoor bottom wall (61b) which is the bottom of the outdoor water storage section (61) is lower than the heat transfer coefficient of the indoor bottom wall (62b) which is the bottom of the indoor water storage section (62).
[0009] According to the above aspect, it is possible to provide a ventilation device (HRV) capable of suppressing condensation on the bottom wall (1e) of the main body casing (1).
[0010] In the ventilation device (HRV) of the above aspect, the thickness (T1) of the outdoor bottom wall (61b) between the bottom surface (6b) of the water receiving tray (6) and the bottom surface (61a) of the outdoor water storage portion (61) may be greater than the thickness (T2) of the indoor bottom wall (62b) between the bottom surface (6b) of the water receiving tray (6) and the bottom surface (62a) of the indoor water storage portion (62). With this configuration, the heat transmission coefficient of the outdoor bottom wall (61b) of the water receiving tray (6) can be made lower than the heat transmission coefficient of the indoor bottom wall (62b).
[0011] In the ventilation device (HRV) of the above aspect, the material of the water tray (6) may be foamed resin. This configuration not only reduces the heat transmission coefficient of the water tray (6), but also reduces the weight of the water tray (6). It also simplifies the manufacture of the water tray (6), reducing manufacturing costs.
[0012] In the ventilation system (HRV) of the above aspect, the water receiving tray (6) may have a water channel (65) connecting the outdoor water storage section (61) and the indoor water storage section (62). With this configuration, water stored in the outdoor water storage section (61) can be transferred to the indoor water storage section (62) through the water channel (65), thereby preventing water from overflowing from the outdoor water storage section (61).
[0013] In the ventilation device (HRV) of the above aspect, the water receiving tray (6) may be a foamed resin molded product having a water channel (65) connecting the outdoor water storage section (61) and the indoor water storage section (62), and the water channel (65) may be a groove having the minimum width (Wmin) that can be formed from the foamed resin molded product. With this configuration, air circulation between the exhaust upstream section (15a) of the exhaust passage (15) and the supply air upstream section (16a) of the supply air passage (16) via the water channel (65) can be suppressed, thereby suppressing a decrease in the effective ventilation rate of the ventilation device (HRV).
[0014] In the ventilation device (HRV) of the above aspect, the thickness (T1) of the outdoor bottom wall (61b) may be 1.1 to 1.5 times the thickness (T2) of the indoor bottom wall (62b). With this configuration, the heat transmission coefficient of the outdoor bottom wall (61b) can be made lower than the heat transmission coefficient of the indoor bottom wall (62b) while ensuring the water storage capacity of the outdoor water storage section (61) and the indoor water storage section (62).
[0015] The ventilation device (HRV) of the above aspect may further include an air supply fan (3) installed in an air supply downstream portion (16b) of the air supply passage (16) connected to an air supply outlet (14) on the indoor end surface (1a) of the main body casing (1), and an exhaust fan (2) installed in an exhaust downstream portion (15b) of the exhaust passage (15) connected to an exhaust outlet (12) on the outdoor end surface (1b) of the main body casing (1).
[0016] With this configuration, when the exhaust fan (2) is operated, room air (RA) is drawn from the exhaust inlet (11) into the exhaust upstream portion (15a) of the exhaust passage (15), passes through the total heat exchanger (4) and the exhaust downstream portion (15b) of the exhaust passage (15), and is blown out as exhaust air (EA) from the exhaust outlet (12). Similarly, when the supply fan (3) is operated, outside air (OA) is drawn from the supply inlet (13) into the supply upstream portion (16a) of the supply passage (16), passes through the total heat exchanger (4) and the supply downstream portion (16b) of the supply passage (16), and is blown out as supply air (SA) from the supply outlet (14).
[0017] For example, if high-humidity outdoor air (OA) and room air (RA) continue to pass through the total heat exchanger (4), the total heat exchanger (4) will absorb and retain water. When the water retention capacity of the total heat exchanger (4) exceeds its limit, water drips from the total heat exchanger (4) and accumulates in the outdoor water reservoir (61) and the indoor water reservoir (62) of the water tray (6). For example, in winter, when the temperature of the outdoor air (OA) is lower than that of the room air (RA), the water accumulated in the outdoor water reservoir (61) is cooled by the outdoor air (OA) passing through the supply air upstream portion (16a) of the supply air passage (16). As a result, the temperature of the water accumulated in the outdoor water reservoir (61) becomes low, close to the temperature of the outdoor air (OA). Even when water is not stored in the outdoor water storage section (61), the outside air (OA) passing through the supply air upstream section (16a) of the air supply passage (16) cools the bottom surface (61a) of the outdoor water storage section (61) to a low temperature close to that of the outside air (OA). However, according to the ventilation device (HRV) of the above aspect, the heat insulating property of the outdoor bottom wall (61b) which is the bottom of the outdoor water storage section (61) in the water receiving tray (6) can be improved, and condensation can be suppressed on the bottom wall (1e) of the main casing (1) which contacts the outdoor bottom wall (61b). [Brief explanation of the drawings]
[0018] [Figure 1] 1 is a longitudinal cross-sectional view schematically illustrating an embodiment of a ventilation device according to the present disclosure. [Figure 2] FIG. 2 is a schematic plan view of the ventilation device (HRV) shown in FIG. [Figure 3] FIG. 2 is a block diagram showing the configuration of the ventilation device (HRV) shown in FIG. [Figure 4] FIG. 2 is a plan view of a water tray of the ventilation device (HRV) shown in FIG. [Figure 5] 5 is a cross-sectional view taken along line VV of the water tray shown in FIG. 4. [Figure 6] 6 is an enlarged cross-sectional view of the water tray taken along line VI-VI of FIG. 4. [Figure 7] 7 is an enlarged cross-sectional view of the water tray taken along line VII-VII of FIG. 4. DETAILED DESCRIPTION OF THE INVENTION
[0019] Hereinafter, an embodiment of a ventilation device according to the present disclosure will be described with reference to the drawings.
[0020] Fig. 1 is a longitudinal cross-sectional view schematically showing an embodiment of a ventilation device according to the present disclosure. Fig. 2 is a schematic plan view of the ventilation device (HRV) of Fig. 1. Fig. 2 is a plan view of the ventilation device (HRV) shown in Fig. 1 with the upper end of the main casing (1) of the ventilation device (HRV) in an open state. Figs. 1 and 2 also show a three-dimensional Cartesian coordinate system having an X axis parallel to the longitudinal direction of the ventilation device (HRV), a Y axis parallel to the width direction of the ventilation device (HRV), and a Z axis parallel to the up-down direction of the ventilation device (HRV).
[0021] The ventilation device (HRV) of this embodiment is installed, for example, in the space above the ceiling (C) that separates the upper part of the indoor space (IDS), i.e., in the attic space (OCS). The ventilation device (HRV) draws in indoor air (RA) from the indoor space (IDS) through, for example, a ventilation opening provided in the ceiling (C) and a ventilation duct (VD), and blows out exhaust air (EA) to the space outside the building through an exhaust duct (EAD) and an exhaust outlet provided in the exterior wall of the building.
[0022] The ventilation system (HRV) draws in outside air (OA) from the space outside the building through an outside air outlet provided on the exterior wall of the building and an outside air duct (OAD), and blows out fresh supply air (SA) into the indoor space (IDS) through an air supply duct (SAD) and an air supply port provided in the ceiling (C). The ventilation system (HRV) also exchanges heat between the indoor air (RA) and the outside air (OA), thereby reducing the temperature difference between the supply air (SA) and the indoor air (RA) supplied to the indoor space (IDS).
[0023] The ventilation device (HRV) includes, for example, a main body casing (1), a total heat exchanger (4), and a water tray (6). The ventilation device (HRV) also includes, for example, an exhaust fan (2), an intake fan (3), and an electrical component box (5).
[0024] The main body casing (1) is, for example, a housing having a roughly rectangular parallelepiped shape. The main body casing (1) has, for example, an exhaust air inlet (11) at an indoor end face (1a) which is the outer surface of the indoor side wall, and an exhaust air outlet (12) at an outdoor end face (1b) which is the outer surface of the outdoor side wall. The main body casing (1) also has an intake air inlet (13) at the outdoor end face (1b) and an intake air outlet (14) at the indoor end face (1a).
[0025] The exhaust inlet (11) is connected to, for example, the downstream end of a ventilation duct (VD). The upstream end of the ventilation duct (VD) is connected to, for example, a ventilation opening provided in the ceiling (C). The exhaust outlet (12) is connected to, for example, the upstream end of an exhaust duct (EAD). The downstream end of the exhaust duct (EAD) is connected to, for example, an exhaust opening provided in the outer wall of the building.
[0026] The supply air inlet (13) is connected to, for example, the downstream end of an outdoor air duct (OAD). The upstream end of the outdoor air duct (OAD) is connected to, for example, an outdoor air port provided on the exterior wall of the building. The supply air outlet (14) is connected to, for example, the upstream end of a supply air duct (SAD). The downstream end of the supply air duct (SAD) is connected to, for example, an air supply port provided in the ceiling (C).
[0027] An exhaust passage (15) and an air intake passage (16) are defined inside the main casing (1), for example, by a partition wall. The exhaust passage (15) connects, for example, the exhaust inlet (11) and the exhaust outlet (12). The air intake passage (16) connects, for example, the air intake inlet (13) and the air intake outlet (14). A total heat exchanger (4) is disposed midway between the exhaust passage (15) and the air intake passage (16). The exhaust passage (15) and the air intake passage (16) are arranged to intersect with the total heat exchanger (4) interposed therebetween, for example, as shown in FIG. 1 .
[0028] The exhaust passage (15) is connected to the exhaust inlet (11) at an upstream exhaust portion (15a) located upstream of the total heat exchanger (4) in the air flow direction and is located below the air supply passage (16). The exhaust passage (15) is connected to the exhaust outlet (12) at a downstream exhaust portion (15b) located downstream of the total heat exchanger (4) in the air flow direction and is located above the air supply passage (16).
[0029] In other words, the air supply passage (16) is connected to the air supply inlet (13) and located below the exhaust passage (15) at an air supply upstream portion (16a) located upstream of the total heat exchanger (4) in the air flow direction, and is located below the exhaust passage (15). Also, the air supply passage (16) is connected to the air supply outlet (14) and located above the air supply passage (16) at an air supply downstream portion (16b) located downstream of the air flow direction, and is located above the air supply passage (16).
[0030] The exhaust fan (2) is installed in an exhaust passage (15) inside the main casing (1). Specifically, the exhaust fan (2) is installed, for example, in an exhaust downstream portion (15b) of the exhaust passage (15) connected to an exhaust outlet (12) on the outdoor end surface (1b) of the main casing (1). The exhaust fan (2) is, for example, a sirocco fan, and includes a casing (21), a cylindrical multi-blade fan (22) housed in the casing (21), and a motor (23) that rotates the multi-blade fan (22).
[0031] The air supply fan (3) is installed in the air supply passage (16) inside the main casing (1). Specifically, the air supply fan (3) is installed, for example, in the air supply downstream portion (16b) of the air supply passage (16) connected to the air supply outlet (14) on the indoor end surface (1a) of the main casing (1). The air supply fan (3) is, for example, a sirocco fan, and includes a casing (31), a cylindrical multi-blade fan (32) housed in the casing (31), and a motor (33) that rotates the multi-blade fan (32).
[0032] The total heat exchanger (4) is disposed in the exhaust passage (15) and the intake passage (16) inside the main casing (1). The total heat exchanger (4) has a heat exchange element in which first and second flow passage forming members made of a thin, dense material that allows water molecules to pass through and blocks out miscellaneous gases such as carbon dioxide are alternately stacked with partition plates made of the same material interposed therebetween. The total heat exchanger (4) has, for example, an elongated rectangular parallelepiped shape as shown in FIGS. 1 and 2. The total heat exchanger (4) has, for example, a diamond shape in a side view perpendicular to the longitudinal direction shown in FIG. 1, and has a first surface (41), a second surface (42), a third surface (43), and a fourth surface (44) along the longitudinal direction of the total heat exchanger (4).
[0033] The first flow path forming member and the partition plate constituting the heat exchange element of the total heat exchanger (4) form, for example, a flow path connecting the first surface (41) and the second surface (42) of the total heat exchanger (4). The first surface (41) of the total heat exchanger (4) is a surface facing obliquely downward and facing the side wall constituting the indoor-side end surface (1a) of the main casing (1), and is connected to the downstream end of the exhaust upstream section (15a) of the exhaust passage (15). The second surface (42) of the total heat exchanger (4) is a surface facing obliquely upward and facing the side wall constituting the outdoor-side end surface (1b) of the main casing (1), and is connected to the upstream end of the exhaust downstream section (15b) of the exhaust passage (15).
[0034] The second flow path forming member and the partition plate constituting the heat exchange element of the total heat exchanger (4) form, for example, a flow path connecting the third surface (43) and the fourth surface (44) of the total heat exchanger (4). The third surface (43) of the total heat exchanger (4) is a surface facing diagonally downward facing the side wall constituting the outdoor-side end surface (1b) of the main casing (1) and is connected to the downstream end of the supply air upstream portion (16a) of the supply air passage (16). The fourth surface (44) of the total heat exchanger (4) is a surface facing diagonally upward facing the side wall constituting the indoor-side end surface (1a) of the main casing (1) and is connected to the upstream end of the supply air downstream portion (16b) of the supply air passage (16).
[0035] The electrical component box (5) is connected to, for example, the main casing (1). Specifically, the main casing (1) has, for example, a first side wall (1c) provided with an outlet (17) of the total heat exchanger (4), as shown in Fig. 2. The electrical component box (5) is connected to, for example, the first side wall (1c) of the main casing (1).
[0036] The first side wall (1c) of the main body casing (1) is, for example, a side wall adjacent to an inspection hatch (C1) provided in the ceiling (C), as shown in Fig. 2. A worker inspecting or maintaining the ventilation system (HRV) accesses the ventilation system (HRV) by, for example, opening the inspection hatch (C1) provided in the ceiling (C). An outlet (17) of the total heat exchanger (4) provided in the first side wall (1c) of the main body casing (1) is closed, for example, by an openable and closable lid (18).
[0037] For example, when performing maintenance or replacing the total heat exchanger (4), a worker opens the lid (18) through the inspection hatch (C1) and opens the outlet (17) of the total heat exchanger (4) provided in the first side wall (1c) of the main casing (1). This allows the worker to pull out the total heat exchanger (4) in the longitudinal direction through the outlet (17) and remove the total heat exchanger (4) from inside the main casing (1).
[0038] The second side wall (1d) of the main casing (1) opposite to the first side wall (1c) of the main casing (1) does not have an outlet (17) for removing the total heat exchanger (4). For example, a bypass flow path is provided between the second side wall (1d) of the main casing (1) and the total heat exchanger (4), which diverts the room air (RA) from the upstream exhaust portion (15a) to the downstream exhaust portion (15b) of the exhaust passage (15) without passing through the total heat exchanger (4). Therefore, it is difficult to remove the total heat exchanger (4) from the second side wall (1d) side.
[0039] FIG. 3 is a block diagram showing the configuration of the ventilation device (HRV) of FIG.
[0040] As shown in FIG. 3, the electrical component box (5) accommodates, for example, a drive circuit (53) for the exhaust fan (2), a drive circuit (54) for the air supply fan (3), and a control circuit (55) that controls the drive circuit (53) and the drive circuit (54).
[0041] The drive circuit (53) of the exhaust fan (2) includes, for example, an inverter circuit that rotates the motor (23) of the exhaust fan (2) at a predetermined rotation speed based on a control command input from the control circuit (55). The drive circuit (54) of the supply fan (3) includes, for example, an inverter circuit that rotates the motor (33) of the supply fan (3) at a predetermined rotation speed based on a control command input from the control circuit (55). The drive circuits (53) and (54) include, for example, power transistors, diodes, and the like that constitute the inverter circuits.
[0042] The control circuit (55) is configured, for example, by one or more microcontrollers including a central processing unit (CPU) and a memory. The control circuit (55) rotates the exhaust fan (2) and the supply fan (3) at a predetermined rotation speed via the drive circuits (53) and (54), for example, by the CPU executing a program stored in the memory. The control circuit (55) is connected, for example, to a carbon dioxide sensor (CDS), a room temperature sensor (RTS), an outside air temperature sensor (OTS), and a remote controller (RC).
[0043] The carbon dioxide sensor (CDS) detects, for example, the carbon dioxide concentration of the room air (RA) and outputs the detection result to the control circuit (55). The room temperature sensor (RTS) detects, for example, the temperature of the room air (RA) and outputs the detection result to the control circuit (55). The outside air temperature sensor (OTS) detects, for example, the temperature of the outside air (OA) and outputs the detection result to the control circuit (55). The remote controller (RC) accepts, for example, operations by the user of the ventilation device (HRV) to start or stop the ventilation device (HRV), and outputs a signal corresponding to the operation to the control circuit (55).
[0044] For example, when a signal corresponding to an operation to start the ventilation device (HRV) is input from the remote controller (RC), the control circuit (55) outputs control signals to the drive circuits (53) and (54) based on the detection results of the carbon dioxide sensor (CDS), the room temperature sensor (RTS), and the outside air temperature sensor (OTS). In response to this, the drive circuits (53) and (54) respectively rotate the motor (23) of the exhaust fan (2) and the motor (33) of the supply fan (3) at predetermined rotation speeds based on the carbon dioxide concentration and temperature of the room air (RA) and the temperature of the outside air (OA).
[0045] The water tray (6) is attached to the wall surface (1ei) of the main casing (1), for example, as shown in Fig. 1, and collects water dripping from the total heat exchanger (4). The wall surface (1ei) of the main casing (1) to which the water tray (6) is attached is, for example, the upper surface of the bottom wall (1e) of the main casing (1). The ventilation device (HRV) is installed with the bottom wall (1e) of the main casing (1) facing downwards so that the bottom wall (1e) of the main casing (1) is approximately horizontal.
[0046] The allowable inclination angle of the bottom wall 1e of the main casing 1 relative to the horizontal plane when installing the HRV is, for example, within 1°. The HRV is usually installed with the bottom wall 1e of the main casing 1 facing downwards, but it is also possible to install the main casing 1 upside down. In this case, a water tray 6 can also be attached to the inner surface 1fi of the top wall 1f, which also serves as the bottom wall of the main casing 1.
[0047] The water tray (6) has, for example, an outdoor water storage portion (61) and an indoor water storage portion (62). The outdoor water storage portion (61) is arranged, for example, in the upstream air supply portion (16a) of the air supply passage (16) connected to the air supply inlet (13) on the outdoor end face (1b) of the main casing (1). The indoor water storage portion (62) is arranged, for example, in the upstream exhaust air portion (15a) of the exhaust air passage (15) connected to the exhaust air inlet (11) of the main casing (1).
[0048] When the water receiving tray (6) is attached to the inner surface (1fi) of the top wall (1f) serving as the bottom wall of the main casing (1) installed upside down, the outdoor water storage section (61) is located, for example, at the exhaust downstream section (15b) of the exhaust passage (15) connected to the exhaust outlet (12) of the main casing (1). In this case, the indoor water storage section (62) of the water receiving tray (6) is located, for example, at the intake downstream section (16b) of the air supply passage (16) connected to the air supply outlet (14). In either case, the water receiving tray (6) located below the total heat exchanger (4) receives water dripping from the total heat exchanger (4) and stores it in the outdoor water storage section (61) and the indoor water storage section (62).
[0049] Fig. 4 is a plan view of the water tray 6 of the ventilation device (HRV) shown in Fig. 1. Fig. 5 is a cross-sectional view of the water tray 6 shown in Fig. 4 taken along line VV.
[0050] The water tray (6) is, for example, a dish-shaped member having a generally rectangular planar shape, and as described above, has an outdoor water storage portion (61) and an indoor water storage portion (62). The water tray (6) also has, for example, a peripheral wall (63) provided around the entire periphery of the water tray (6), and a partition wall (64) provided in the center of the water tray (6) in the short direction (X-axis direction) and extending along the long direction (Y-axis direction) of the water tray (6).
[0051] The outdoor water storage section (61) includes, for example, one side portion of a peripheral wall (63) and one side portion of a partition wall (64) disposed in the intake air upstream section (16a) inside the main casing (1). The outdoor water storage section (61) has a bottom surface (61a) surrounded by the peripheral wall (63) and the partition wall (64), and stores water on this bottom surface (61a). The bottom surface (61a) of the outdoor water storage section (61) is, for example, the upper surface of an outdoor bottom wall (61b) that is the bottom wall of the outdoor water storage section (61). The bottom surface (61a) of the outdoor water storage section (61) is, for example, a flat surface, but may have recesses or protrusions.
[0052] The indoor water storage portion (62) includes, for example, one side portion of a peripheral wall (63) and one side portion of a partition wall (64) disposed in the exhaust upstream portion (15a) inside the main casing (1). The indoor water storage portion (62) has a bottom surface (62a) surrounded by the peripheral wall (63) and the partition wall (64), and stores water on the bottom surface (62a). The bottom surface (62a) of the indoor water storage portion (62) is, for example, the upper surface of the indoor bottom wall (62b) that is the bottom wall of the indoor water storage portion (62). The bottom surface (62a) of the indoor water storage portion (62) is, for example, a flat surface, but may have recesses or protrusions.
[0053] As shown in Fig. 5, the bottom of the outdoor water storage portion (61) is defined by an outdoor bottom wall (61b) which is the bottom wall of the outdoor water storage portion (61). The bottom of the indoor water storage portion (62) is defined by an indoor bottom wall (62b) which is the bottom wall of the indoor water storage portion (62). In the water tray (6), the outdoor bottom wall (61b) has a lower heat transmission coefficient than the indoor bottom wall (62b).
[0054] The heat transmission coefficient of the outdoor bottom wall (61b) is a value that indicates the ease of heat transfer when heat transfer occurs, for example, between the bottom surface (6b) of the water tray (6) and the bottom surface (61a) of the outdoor water storage section (61). Similarly, the heat transmission coefficient of the indoor bottom wall (62b) is a value that indicates the ease of heat transfer when heat transfer occurs, for example, between the bottom surface (6b) of the water tray (6) and the bottom surface (62a) of the indoor water storage section (62). The heat transmission coefficient can be measured, for example, by the measurement method specified in Japanese Industrial Standard JIS A 1420:1999.
[0055] Specifically, for example, the thickness (T1) of the outdoor bottom wall (61b) between the bottom surface (6b) of the water tray (6) and the bottom surface (61a) of the outdoor water storage portion (61) is greater than the thickness (T2) of the indoor bottom wall (62b) between the bottom surface (6b) of the water tray (6) and the bottom surface (62a) of the indoor water storage portion (62). Although not particularly limited, the thickness (T1) of the outdoor bottom wall (61b) is, for example, 1.1 to 1.5 times the thickness (T2) of the indoor bottom wall (62b). Here, the thickness (T1) of the outdoor bottom wall (61b) is, for example, the thickness of the bottom surface (61a) of the outdoor water storage portion (61) excluding any convex or concave portions. The same applies to the thickness (T2) of the indoor bottom wall (62b). The thickness (T1) of the outdoor bottom wall (61b) may be, for example, 10.5 mm, which is the thickness required for thermal insulation, and the thickness (T2) of the indoor bottom wall (62b) may be, for example, 8 mm, which is the minimum thickness required for manufacturing.
[0056] The material of the water receiving tray (6) is, for example, a foamed resin. That is, the water receiving tray (6) is, for example, a foamed resin molded product. In this case, for example, the foaming ratio of the outdoor-side bottom wall (61b) may be made different from the foaming ratio of the indoor-side bottom wall (62b), thereby making the insulating performance of the outdoor-side bottom wall (61b) different from that of the indoor-side bottom wall (62b). For example, the foaming ratio of the outdoor-side bottom wall (61b) may be made higher than that of the indoor-side bottom wall (62b).
[0057] As a result, even if the thickness (T1) of the outdoor bottom wall (61b) and the thickness (T2) of the indoor bottom wall (62b) are the same, the heat transmission coefficient of the outdoor bottom wall (61b) can be made smaller than that of the indoor bottom wall (62b). The outdoor bottom wall (61b) and the indoor bottom wall (62b) may be made of different materials. In this case, the outdoor bottom wall (61b) may be made of a material having a lower heat transmission coefficient than the material of the indoor bottom wall (62b).
[0058] The peripheral wall (63) and the partition wall (64) of the water receiving tray (6) have a gradient such that the thicknesses (T3) and (T4) increase toward the bottom surface (61a) of the outdoor water storage section (61) or the bottom surface (62a) of the indoor water storage section (62), as shown in Fig. 5. A concave groove (63a) and a concave groove (64a) are formed at the upper end of the peripheral wall (63) and the upper end of the partition wall (64) of the water receiving tray (6), respectively, across the boundary (B) between the outdoor water storage section (61) and the indoor water storage section (62), as shown in Figs. 4 and 5. The concave shape may be, for example, V-shaped or U-shaped.
[0059] The shapes of the groove (63a) of the peripheral wall (63) and the groove (64a) of the partition wall (64) correspond to the shapes of the corners between the first surface (41) and the third surface (43) of the total heat exchanger (4), for example, as shown in Fig. 1. This allows the corners at the lower end of the total heat exchanger (4) to fit snugly into the groove (63a) at the upper end of the peripheral wall (63) and the groove (64a) at the upper end of the partition wall (64), and enter the grooves (63a) and (64a).
[0060] With this configuration, when the lid (18) of the main casing (1) shown in Fig. 2 is opened and the total heat exchanger (4) is removed from the main casing (1) through the outlet (17), the corners of the lower end of the total heat exchanger (4) can slide along the grooves (63a) of the peripheral wall (63) and the grooves (64a) of the partition wall (64). When the total heat exchanger (4) is inserted into the main casing (1) through the outlet (17), the corners of the lower end of the total heat exchanger (4) can slide along the grooves (63a) of the peripheral wall (63) and the grooves (64a) of the partition wall (64).
[0061] The groove 63a provided in the peripheral wall 63 of the water receiving tray 6 adjacent to the second side wall 1d opposite to the first side wall 1c where the outlet 17 of the main casing 1 is provided may be omitted as long as there is no problem with removing and inserting the total heat exchanger 4. That is, the groove 63a in the peripheral wall 63 of the water receiving tray 6 may be provided, for example, only at a position adjacent to the outlet 17 of the total heat exchanger 4 provided in the main casing 1.
[0062] 5, the height (H1) from the bottom surface (61a) of the outdoor water storage portion (61) to the upper end of the peripheral wall (63) and the height (H2) from the bottom surface (62a) of the indoor water storage portion (62) to the upper end of the peripheral wall (63) are determined, for example, based on the full water level (FWL) of the outdoor water storage portion (61) and the indoor water storage portion (62). Specifically, the heights (H1) and (H2) of the peripheral wall (63) are determined, for example, when the main casing (1) of the ventilation device (HRV) is installed at an inclination within an allowable range.
[0063] The peripheral wall (63) has, for example, a groove (63a) at its upper end. In this case, the heights (H1) and (H2) of the peripheral wall (63) are determined so that the bottom of the groove (63a) is located above the full water level (FWL) even when, for example, the main casing (1) of the ventilation device (HRV) is installed at an inclination within an allowable range. Furthermore, the heights (H1) and (H2) of the peripheral wall (63) are determined so that the water will not overflow when the water at the full water level (FWL) stored in the outdoor water reservoir (61) and the indoor water reservoir (62) becomes rippled due to the outside air (OA) and the room air (RA) passing over the water tray (6) during operation of the ventilation device (HRV).
[0064] The amounts of water stored at the full water level (FWL) in the outdoor water reservoir (61) and the indoor water reservoir (62) are determined so that water does not overflow from the outdoor water reservoir (61) and the indoor water reservoir (62) when the ventilation system (HRV) is operated continuously for three days under conditions that cause the greatest amount of water to drip from the total heat exchanger (4). The conditions that cause the greatest amount of water to drip from the total heat exchanger (4) are, for example, conditions where the outdoor air is hot and humid and the ventilation system (HRV) continues to operate after the air conditioning system in the room is turned off.
[0065] Fig. 6 is an enlarged cross-sectional view of the water tray (6) taken along line VI-VI shown in Fig. 4. Fig. 7 is an enlarged cross-sectional view of the water tray (6) taken along line VII-VII shown in Fig. 4.
[0066] The water receiving tray (6) has, for example, a water channel (65) connecting the outdoor water storage section (61) and the indoor water storage section (62). The water channel (65) is provided, for example, to cross a partition wall (64) that separates the outdoor water storage section (61) from the indoor water storage section (62), and is a flow path for allowing water to flow from the outdoor water storage section (61) to the indoor water storage section (62).
[0067] The water channels 65 are, for example, grooves or slits formed between the peripheral wall 63 and the partition wall 64 by removing a portion of the partition wall 64 in the longitudinal direction. In the example shown in Fig. 4, the water channels 65 are formed at both longitudinal end portions of the partition wall 64. However, the positions at which the water channels 65 are formed and the number of the water channels 65 are not particularly limited. The water channels 65 may be formed, for example, at one longitudinal end portion of the partition wall 64 or in the longitudinal middle portion of the partition wall 64.
[0068] When the water tray 6 is a foam resin molded product having a water channel 65, for example, as shown in FIG. 7, the peripheral wall 63 and the partition wall 64 constituting the side walls on both sides of the water channel 65 in the width direction have a predetermined slope required for molding. Therefore, the water channel 65 has, for example, a maximum width (Wmax) at the opening at the upper end and a minimum width (Wmin) at the bottom surface 65a at the lower end. This minimum width (Wmin) is, for example, the minimum width that can be molded from a foam resin molded product. In other words, the water channel 65 is, for example, a groove with the minimum width (Wmin) that can be molded from a foam resin molded product. The minimum width (Wmin) of the water channel 65 is preferably as small as possible within the range that allows water to flow, for example, approximately 1 mm to 15 mm.
[0069] 6, the bottom surface (65a) of the water channel (65) may be flush with the bottom surface (62a) of the indoor water reservoir (62) at the end adjacent to the outdoor water reservoir (61), with a difference in level between the end and the bottom surface (61a) of the outdoor water reservoir (61). The bottom surface (65a) of the water channel (65) may be gradually reduced in height from the bottom surface (61a) of the outdoor water reservoir (61) to the bottom surface (62a) of the indoor water reservoir (62). The bottom surface (65a) of the water channel (65) may be flush with the bottom surface (61a) of the outdoor water reservoir (61) up to the end adjacent to the bottom surface (62a) of the indoor water reservoir (62), with a difference in level between the end and the bottom surface (62a) of the indoor water reservoir (62).
[0070] The water receiving tray (6) may also have a water-permeable shielding member (66) disposed in the water channel (65), as shown in Fig. 6. The water-permeable shielding member (66) is disposed, for example, so as to fill a gap formed between the total heat exchanger (4) disposed on the water receiving tray (6) and the water channel (65) of the water receiving tray (6). The water-permeable shielding member (66) may be made of a material, such as a sponge, that allows water flowing through the water channel (65) to pass through and blocks the flow of air passing through the water channel (65).
[0071] The operation of the ventilator (HRV) of this embodiment will be described below.
[0072] As described above, the ventilation device (HRV) of this embodiment includes a main casing (1), a total heat exchanger (4), and a water receiving tray (6). The total heat exchanger (4) is installed inside the main casing (1) midway through the air supply passage (16) and the air exhaust passage (15). The water receiving tray (6) is attached to the wall surface (1ei) of the main casing (1) and collects water dripping from the total heat exchanger (4). The water receiving tray (6) has an outdoor water reservoir (61) and an indoor water reservoir (62). The outdoor water reservoir (61) is located in the intake air upstream portion (16a) of the air supply passage (16) connected to the intake air inlet (13) on the outdoor end surface (1b) of the main casing (1). The indoor water storage portion (62) is disposed in the exhaust upstream portion (15a) of the exhaust passage (15) connected to the exhaust inlet (11) on the indoor end surface (1a) of the main casing (1). The heat transmission coefficient of the outdoor bottom wall (61b) which is the bottom of the outdoor water storage portion (61) is lower than the heat transmission coefficient of the indoor bottom wall (62b) which is the bottom of the indoor water storage portion (62).
[0073] With this configuration, the ventilation device (HRV) of this embodiment can take in room air (RA) from the indoor space (IDS) into the exhaust passage (15) inside the main casing (1) through, for example, a ventilation opening and a ventilation duct (VD) provided in the ceiling (C). In addition, the ventilation device (HRV) can pass the room air (RA) taken in into the exhaust passage (15) through the total heat exchanger (4) and discharge the air from the exhaust passage (15) to the outdoors as exhaust air (EA) through, for example, an exhaust duct (EAD) and an exhaust port provided in the exterior wall of the building.
[0074] The ventilation system (HRV) can take in outside air (OA) from an outdoor space into the air supply passage (16) inside the main casing (1), for example, through an outside air port and an outside air duct (OAD) provided on the exterior wall of the building. The ventilation system (HRV) passes the outside air (OA) taken into the air supply passage (16) through the total heat exchanger (4), and can exchange heat and transfer water molecules between the outside air (OA) and the indoor air (RA) that is discharged outdoors. The ventilation system (HRV) can supply the supply air (SA) obtained after the outside air (OA) has passed through the total heat exchanger (4) from the air supply passage (16) to the indoor space (IDS), for example, through the air supply duct (SAD) and an air supply port provided in the ceiling (C).
[0075] For example, if high-humidity outdoor air (OA) and room air (RA) continue to pass through the total heat exchanger (4), the total heat exchanger (4) will absorb and retain water. When the water retention capacity of the total heat exchanger (4) exceeds its limit, water drips from the total heat exchanger (4) and is stored in the outdoor water reservoir (61) and the indoor water reservoir (62) of the water tray (6) attached to the wall surface (1ei) of the main casing (1). For example, if the temperature of the outdoor air (OA) is lower than the temperature of the room air (RA), the water stored in the outdoor water reservoir (61) is cooled to a temperature close to that of the outdoor air (OA) by the outdoor air (OA) passing over the outdoor water reservoir (61). Even when water is not stored in the outdoor water storage section (61), the bottom surface (61a) of the outdoor water storage section (61) is cooled by the outside air (OA) passing through the upstream air supply section (16a) of the air supply passage (16) to a low temperature close to that of the outside air (OA).
[0076] In the water tray (6) of the ventilation system (HRV) of this embodiment, the heat transmission coefficient of the outdoor bottom wall (61b), which is the bottom of the outdoor water storage portion (61), is set lower than the heat transmission coefficient of the indoor bottom wall (62b), which is the bottom of the indoor water storage portion (62). This improves the thermal insulation of the outdoor bottom wall (61b). Therefore, even if the temperature of the bottom surface (61a) of the outdoor water storage portion (61) is reduced due to cooling by the water stored in the outdoor water storage portion (61) or the outside air (OA) passing over the water tray (6), heat loss from the wall surface (1ei) of the main casing (1) to which the water tray (6) is attached is suppressed by the water stored in the outdoor water storage portion (61) or the outside air (OA) passing over the water tray (6). As a result, condensation on the bottom wall (1e) of the main casing (1) to which the water tray (6) is attached can be suppressed.
[0077] Meanwhile, in the exhaust upstream portion (15a) of the exhaust passage (15) provided inside the main casing (1), water retained in the total heat exchanger (4) drips from the total heat exchanger (4) when the water retention capacity of the total heat exchanger (4) exceeds its limit. The water dripping from the total heat exchanger (4) in the exhaust upstream portion (15a) of the exhaust passage (15) is received and stored in the indoor water reservoir (62) of the water receiver (6) attached to the wall surface (1ei) of the main casing (1). The water stored in the indoor water reservoir (62) is heated to a temperature close to that of the room air (RA) by the room air (RA) passing over the indoor water reservoir (62).
[0078] Therefore, even if the heat transmission coefficient of the indoor-side bottom wall (62b) constituting the bottom of the indoor-side water storage portion (62) is set to be higher than that of the outdoor-side bottom wall (61b) constituting the bottom of the outdoor-side water storage portion (61), the heat of the wall surface (1e) of the main casing (1) is not taken away by the water stored in the indoor-side water storage portion (62) or the air passing over the water receiving tray (6). Therefore, by making the heat transmission coefficient of the outdoor-side bottom wall (61b) of the water receiving tray (6) lower than that of the indoor-side bottom wall (62b), it is possible to suppress condensation on the bottom wall (1e) of the main casing (1).
[0079] In the ventilation device (HRV) of this embodiment, the thickness (T1) of the outdoor bottom wall (61b) between the bottom surface (6b) of the water receiving tray (6) and the bottom surface (61a) of the outdoor water storage portion (61) is greater than the thickness (T2) of the indoor bottom wall (62b) between the bottom surface (6b) of the water receiving tray (6) and the bottom surface (62a) of the indoor water storage portion (62). With this configuration, the heat transmission coefficient of the outdoor bottom wall (61b) of the water receiving tray (6) can be made lower than the heat transmission coefficient of the indoor bottom wall (62b).
[0080] In the ventilation device (HRV) of this embodiment, the material of the water tray (6) is foamed resin. This configuration not only reduces the heat transmission coefficient of the water tray (6), but also reduces the weight of the water tray (6). It also simplifies the manufacture of the water tray (6), reducing manufacturing costs.
[0081] In the ventilation system (HRV) of this embodiment, the water receiving tray (6) has a water channel (65) connecting the outdoor water storage portion (61) and the indoor water storage portion (62).
[0082] With this configuration, water stored in the outdoor water storage section (61) is transferred to the indoor water storage section (62) through the water channel (65), thereby preventing the outdoor water storage section (61) from overflowing. Specifically, for example, by making the thickness (T1) of the outdoor bottom wall (61b) larger than the thickness (T2) of the indoor bottom wall (62b), the maximum water storage capacity of the outdoor water storage section (61) is reduced compared to the maximum water storage capacity of the indoor water storage section (62). However, by transferring water from the outdoor water storage section (61) to the indoor water storage section (62) through the water channel (65), the reduced water storage capacity of the outdoor water storage section (61) can be compensated for by the indoor water storage section (62), which has a larger maximum water storage capacity than the outdoor water storage section (61).
[0083] In addition, in the ventilation device (HRV) of this embodiment, the water receiving tray (6) is a foamed resin molded product having a water channel (65) connecting the outdoor water storage section (61) and the indoor water storage section (62), and the water channel (65) is a groove of the minimum width (Wmin) that can be molded in a foamed resin molded product.
[0084] This configuration facilitates the production of the water receiving tray (6) having the water channel (65), thereby reducing the manufacturing cost. Furthermore, by forming the water receiving tray (6) as a groove of the minimum width (Wmin) of a foamed resin molded product, air is prevented from flowing between the exhaust passage (15) and the air supply passage (16) through the water channel (65) inside the main casing (1), thereby preventing a decrease in the effective ventilation rate.
[0085] In the water tray (6) of the ventilation device (HRV) of this embodiment, the thickness (T1) of the outdoor bottom wall (61b) is 1.1 to 1.5 times the thickness (T2) of the indoor bottom wall (62b). This configuration makes the outdoor bottom wall (61b) have a lower heat transmission coefficient than the indoor bottom wall (62b), thereby more effectively suppressing condensation on the bottom wall (1e) of the main casing (1) and more reliably ensuring the amount of water stored in the outdoor water storage portion (61) and the indoor water storage portion (62).
[0086] The ventilation device (HRV) of this embodiment further includes an intake fan (3) and an exhaust fan (2). The intake fan (3) is installed in an intake downstream portion (16b) of an intake passage (16) connected to an intake outlet (14) on the indoor end surface (1a) of the main casing (1). The exhaust fan (2) is installed in an exhaust downstream portion (15b) of an exhaust passage (15) connected to an exhaust outlet (12) on the outdoor end surface (1b) of the main casing (1).
[0087] With this configuration, when the exhaust fan (2) is operated, indoor air is drawn from the exhaust inlet (11) into the exhaust upstream portion (15a) of the exhaust passage (15), passes through the total heat exchanger (4) and the exhaust downstream portion (15b) of the exhaust passage (15), and is blown out as exhaust air from the exhaust outlet (12). Similarly, when the supply fan (3) is operated, outside air is drawn from the supply inlet (13) into the supply upstream portion (16a) of the supply passage (16), passes through the total heat exchanger (4) and the supply downstream portion (16b) of the supply passage (16), and is blown out as supply air from the supply outlet (14).
[0088] Therefore, as described above, in winter when the temperature of the outdoor air (OA) is lower than the temperature of the indoor air (RA), water drips from the total heat exchanger (4) and accumulates in the outdoor water reservoir (61) of the water tray (6) in the upstream air supply section (16a) of the air supply passage (16) of the main casing (1) when the water capacity of the total heat exchanger (4) exceeds its limit. This water is cooled by the outdoor air (OA) passing through the upstream air supply section (16a) of the air supply passage (16). As a result, the temperature of the water accumulated in the outdoor water reservoir (61) becomes low, close to the temperature of the outdoor air (OA). Even when no water is accumulated in the outdoor water reservoir (61), the bottom surface (61a) of the outdoor water reservoir (61) is cooled by the outdoor air (OA) passing through the upstream air supply section (16a) of the air supply passage (16) to become low, close to the temperature of the outdoor air (OA). However, according to the ventilation device (HRV) of this embodiment, the heat insulating properties of the outdoor bottom wall (61b), which is the bottom of the outdoor water storage section (61), in the water receiving tray (6) can be improved, and condensation on the bottom wall (1e) of the main casing (1) that contacts the outdoor bottom wall (61b) can be suppressed.
[0089] As described above, according to this embodiment, it is possible to provide a ventilation device (HRV) that can suppress condensation on the bottom wall (1e) of the main casing (1).
[0090] The preferred embodiments of the present disclosure have been described above in detail. However, the present disclosure is not limited to the above-described embodiments. Various modifications or substitutions may be applied to the above-described embodiments without departing from the scope of the present disclosure. Furthermore, features described separately may be combined unless technical contradictions arise. [Explanation of symbols]
[0091] 1 Main casing 1a Indoor end surface 1b Outdoor end surface 1ei wall 11 Exhaust inlet 12 Exhaust outlet 13 Air intake inlet 14 Air intake outlet 15 Exhaust passage 15a Upstream exhaust 15b downstream exhaust 16 Air supply passage 16a Air supply upstream 16b Air intake downstream part ( 2 exhaust fans 3 Intake fan 4 Total heat exchanger 6 Water tray 61 Outdoor water storage section 61a bottom 61b Outdoor bottom wall 62 Indoor water storage section 62a bottom 62b Indoor bottom wall 65 Waterways HRV ventilation device T1 Thickness T2 Thickness Wmin Minimum width
Claims
1. A main body casing (1), a total heat exchanger (4) installed in the intake passage (16) and the exhaust passage (15) inside the main casing (1); a water tray (6) attached to a wall surface (1ei) of the main casing (1) for collecting water dripping from the total heat exchanger (4); The water tray (6) has an outdoor water storage section (61) arranged in an upstream air supply section (16a) of the air supply passage (16) connected to an air supply inlet (13) on an outdoor end surface (1b) of the main body casing (1), and an indoor water storage section (62) arranged in an upstream exhaust air section (15a) of the exhaust air passage (15) connected to an exhaust air inlet (11) on an indoor end surface (1a) of the main body casing (1), The heat transmission coefficient of the outdoor bottom wall (61b) of the bottom of the outdoor water storage section (61) is lower than the heat transmission coefficient of the indoor bottom wall (62b) of the bottom of the indoor water storage section (62). Ventilation device (HRV).
2. a thickness (T1) of the outdoor bottom wall (61b) between the bottom surface (6b) of the water tray (6) and the bottom surface (61a) of the outdoor water storage section (61) is greater than a thickness (T2) of the indoor bottom wall (62b) between the bottom surface (6b) of the water tray (6) and the bottom surface (62a) of the indoor water storage section (62); 2. A ventilation device (HRV) according to claim 1.
3. The material of the water tray (6) is foamed resin. The ventilation device according to claim 1 or 2.
4. The water tray (6) has a water channel (65) connecting the outdoor water storage portion (61) and the indoor water storage portion (62). The ventilation device according to claim 1 or 2.
5. The water tray (6) is a foamed resin molded product having a water channel (65) connecting the outdoor water storage portion (61) and the indoor water storage portion (62), The water channel (65) is a groove having the minimum width (Wmin) that can be formed in the foamed resin molded product. The ventilation device according to claim 1 or 2.
6. The thickness (T1) of the outdoor bottom wall (61b) is 1.1 times or more and 1.5 times or less the thickness (T2) of the indoor bottom wall (62b).
3. The ventilation device of claim 2.
7. an air supply fan (3) installed in an air supply downstream portion (16b) of the air supply passage (16) connected to an air supply outlet (14) on the indoor end surface (1a) of the main casing (1); an exhaust fan (2) installed in an exhaust downstream portion (15b) of the exhaust passage (15) connected to the exhaust outlet (12) on the outdoor end surface (1b) of the main body casing (1), 10. The ventilation device of claim 1.
Citation Information
Patent Citations
Indoor unit of air conditioning device
JP2020085403A
Ventilation device
JP2022075246A