Blowout air amount adjustment device

Abstract

To provide a blowout air amount adjustment device capable of reducing pressure loss of an air duct with a simple configuration.SOLUTION: A blowout air amount adjustment device (40) is applied to a duct-type air conditioning system that supplies conditioned air from an air conditioner to a habitable room (101) through a duct (34). The blowout air amount adjustment device comprises: a case part (41) connected to a downstream end part of the duct, and having a first air channel (F1) from an inflow port (401) for conditioned air to a first blowout port (402a) and a second air channel (F2) from the inflow port to a second blowout port (402b); and a supply air fan (42) that is arranged on the second air channel in the case part, and operates under a predetermined condition.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a variable discharge air volume device, and more particularly to a variable discharge air volume device applied to a "ducted air conditioning system" that supplies conditioned air from an air conditioner to a room via a duct. [Background technology]

[0002] A ducted air conditioning system is generally installed in a centrally air-conditioned home. For example, in Japanese Patent Application Laid-Open No. 2020-159680 (Patent Document 1), an air conditioner and a blower are installed in a machine room, and conditioned air from the air conditioner is supplied to multiple rooms through multiple ducts.

[0003] In duct-type air conditioning systems, a variable air volume device has been proposed that varies the air volume by installing a fan midway through the air passage (duct), as disclosed in Japanese Patent Laid-Open Publication No. 2008-51466 (Patent Document 2). In this document, a pressure sensor is used to measure the static pressure in the duct, and the pressure upstream of the fan is controlled so that it does not become excessively high. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-159680 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-51466 Summary of the Invention [Problem to be solved by the invention]

[0005] Global warming has become a serious problem these days. If Japan's hot and humid weather continues to worsen, it is predicted that the outdoor temperature will rise by 2 degrees by 2086. There is also a possibility that the dew point temperature will exceed 27 degrees. If this happens, it is predicted that the cooling efficiency of conventional ducted air conditioning systems will decrease and the risk of condensation will increase.

[0006] Patent Document 2 proposes a variable air volume device that can adjust the volume of air blown into each room, but because the fan for adjusting the volume of air is installed in the air duct, the following problems arise: If the air conditioning equipment is used with the fan stopped, pressure loss in the air duct increases, resulting in increased power consumption. For this reason, the fan cannot be stopped. In addition, a separate sensor or the like must be used to adjust the volume of air, which increases costs and the number of materials required.

[0007] The present invention has been made to solve the above-mentioned problems, and its object is to provide a variable blow-out air volume device that has a simple configuration and can reduce pressure loss in the air duct of conditioned air. [Means for solving the problem]

[0008] A variable discharge air volume device according to one aspect of the present invention is applied to a ducted air conditioning system that supplies conditioned air from an air conditioner to a room through a duct. The variable discharge air volume device includes a case connected to the downstream end of the duct and having a first air passage from an air inlet for conditioned air to a first air outlet and a second air passage from the air inlet to a second air outlet, and a supply air fan disposed on the second air passage within the case and operating under predetermined conditions.

[0009] Preferably, the variable blowout air volume device further includes an air supply control unit that operates the air supply fan when the room temperature satisfies a predetermined room temperature condition, and stops the air supply fan when the room temperature does not satisfy the predetermined room temperature condition.

[0010] The supply air control unit preferably controls the supply air fan based on the room temperature detected by a temperature sensor used in the ducted air conditioning system.

[0011] In one embodiment, the ducted air conditioning system has a damper for adjusting the opening degree of each duct, and the supply air control unit desirably stops the supply air fan when the opening degree of the damper is less than a predetermined opening degree, regardless of room temperature conditions.

[0012] The variable blow air volume device may further include a backflow prevention means for preventing conditioned air blown out from the second blowout port from flowing back out from the first blowout port when the air supply fan is operating. [Effects of the Invention]

[0013] According to the present invention, it is possible to reduce pressure loss in the air duct of conditioned air with a simple configuration. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a diagram showing a schematic configuration of a ducted air conditioning system according to an embodiment of the present invention and the installation position of a blow-out air volume variable device; [Figure 2] 1 is a diagram showing a basic configuration of a blow-out air volume variable device according to an embodiment of the present invention; [Figure 3] 1 is a diagram illustrating a configuration example of a blowout air volume variable device according to an embodiment of the present invention. [Figure 4] 2 is a block diagram showing the functional configuration of a ducted air conditioning system and a variable blow-out air volume device. FIG. [Figure 5] 4 is a flowchart showing a process executed by an air supply control unit of the variable blow air volume device according to the embodiment of the present invention. [Figure 6] FIG. 10 is a diagram showing an example of a backflow prevention means. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, in which like or corresponding parts are designated by like reference numerals and will not be described repeatedly.

[0016] The variable blow air volume device according to this embodiment is applied to a "ducted air conditioning system" that provides whole-building air conditioning for a building such as a house. In a ducted air conditioning system, conditioned air from an air conditioner is supplied to rooms through ducts.

[0017] (Basic configuration of ducted air conditioning systems) First, the basic configuration of a ducted air conditioning system 10 according to this embodiment will be described with reference to Figures 1 and 4. Figure 1 is a diagram showing the general configuration of the ducted air conditioning system 10 and the installation position of a discharge air volume variable device 40. Figure 4 is a block diagram showing the functional configuration of the ducted air conditioning system 10 and the discharge air volume variable device 40.

[0018] The ducted air conditioning system 10 according to this embodiment performs whole-house air conditioning for a house 100. The house 100 is, for example, a two-story detached house.

[0019] Ducted air conditioning system 10 includes, for example, an air conditioner 31 and a blower fan 32 installed in a machine room 110, a branch chamber 33 provided in the attic space 120 above the machine room 110, and multiple ducts 34 extending from the branch chamber 33 to an outlet in an occupant room 101 to be air-conditioned. In the example shown, machine room 110 is provided facing a non-occupant room 102, and takes in air from non-occupant room 102 and exchanges heat with the taken-in air in air conditioner 31.

[0020] A damper 35 with an adjustable opening is provided at the upstream end (on the branch chamber 33 side) of each duct 34. The air conditioning control unit 11 of the ducted air conditioning system 10 adjusts the opening of each damper 35, thereby adjusting the blown air volume for each room 101. The air conditioning control unit 11 typically adjusts the opening of the damper 35 based on the room temperature of the room 101 to be air-conditioned. For this reason, each room 101 to be air-conditioned is provided with a temperature sensor 36 for detecting the room temperature. The air conditioning control unit 11 controls the drive of the air conditioner 31 and the blower fan 32, and adjusts the opening of the damper 35 corresponding to each room 101 based on the room temperature of each room 101 detected by the temperature sensor 36.

[0021] If the capacity of the air conditioner 31 and blower fan 32 in the ducted air conditioning system 10 is designed based on current weather conditions, there is a risk that simply adjusting the opening of the damper 35 will not be enough to respond to future weather changes (temperature rises). In other words, there is a risk that the cooling effect will deteriorate in the future (for example, 10 years from now). It is also expected that the risk of condensation will increase. In this embodiment, to reduce such risks, a discharge airflow volume variable device 40 is provided at the most downstream position of the air duct for conditioned air in the ducted air conditioning system 10, as shown in FIG. 1.

[0022] A discharge air volume variable device 40 is provided for each room 101 to be air-conditioned (the same as the number of ducts 34). In other words, the ducted air conditioning system 10 and multiple discharge air volume variable devices 40 make up a whole-house air-conditioning system 1 for the house 100. The whole-house air-conditioning system 1 makes it possible to adjust (increase) the volume of air discharged into each room 101 without changing the basic configuration of the ducted air-conditioning system 10. The discharge air volume variable device 40 can be installed as an add-on to the basic components of the ducted air-conditioning system 10.

[0023] (Configuration of variable blow air volume device) The basic configuration of the discharge air volume variable device 40 will be described with reference to Fig. 2. Fig. 2 is a cross-sectional view that schematically shows the basic configuration of the discharge air volume variable device 40. As shown in Fig. 1, the discharge air volume variable device 40 is disposed on the ceiling of each living room 101.

[0024] 2, variable airflow control device 40 includes case 41 arranged in ceiling space 120 of room 101, and supply fan 42 arranged within case 41. Case 41 has inlet 401 through which conditioned air flows in from duct 34, and outlet 402 through which conditioned air flows into room 101. Case 41 is, for example, in the shape of a rectangular parallelepiped, and has inlet 401 provided on side surface 411 connected to duct 34, and outlet 402 provided on bottom surface 412.

[0025] As shown in FIG. 4, the variable airflow device 40 also includes an air supply control unit 46 that controls the air supply fan 42. The air supply control unit 46 controls the ON / OFF of the air supply fan 42 based on the room temperature detected by the temperature sensor 36 (i.e., the temperature sensor 36 used in the ducted air-conditioning system 10). Specifically, the air supply fan 42 operates when the room temperature of the target room 101 satisfies a predetermined room temperature condition, and stops when the room temperature of the target room 101 does not satisfy the predetermined room temperature condition. The "predetermined room temperature condition" indicates, for example, that the temperature difference between the temperature set in the room 101 by the ducted air-conditioning system 10 and the actual temperature is equal to or greater than a predetermined value (e.g., 1 degree). The set temperature is typically a temperature set in advance by the user.

[0026] By providing such a variable blow air volume device 40 for each room 101 to be air-conditioned, the air-conditioning capacity of the room 101 can be increased compared to the existing duct type air-conditioning system 10.

[0027] 2 has only one air outlet 402, so the conditioned air passes through a common air path in both the mechanical air supply mode (air supply fan 42 is ON) and the natural air supply mode (air supply fan 42 is OFF). Therefore, in the natural air supply mode, air supply fan 42 acts as a resistance, resulting in a large pressure loss.

[0028] To solve this problem, it is desirable to separate air passage F1 for the natural air supply mode and air passage F2 for the mechanical air supply mode, as in discharge air volume variable device 40A shown in Fig. 3. That is, it is desirable to provide two air outlets 402a, 402b in case 41, with a first air passage F1 extending from inlet 401 to first air outlet 402a and a second air passage F2 extending from inlet 401 to second air outlet 402b, and not to install a fan in first air passage F1, but to install supply fan 42 only in second air passage F2.

[0029] Air passages F1 and F2 will now be described in detail. The internal space of case 41 is divided into two spaces 44a and 44b by partition member 43 arranged opposite air inlet 401. No fan is provided in space 44a closer to air inlet 401 (hereinafter referred to as the "front space"), and air supply fan 42 is provided only in space 44b farther from air inlet 401 (hereinafter referred to as the "rear space"). Front space 44a constitutes first air passage F1, and rear space 44b constitutes second air passage F2.

[0030] The partition member 43 is a plate-like member that rises upward from the bottom surface 412 of the case portion 41. A passage 403 that connects the two spaces 44a, 44b is provided between the upper end of the partition member 43 and the top surface 413 of the case portion 41. The first air passage F1 is an air supply path that runs from the inlet 401 through the front space 44a to the outlet 402a. The second air passage F2 is an air supply path that runs from the inlet 401 through the front space 44a, the passage 403, and the back space 44b in this order to the outlet 402b.

[0031] 3, when supply fan 42 is OFF (in natural air supply mode), conditioned air that flows into front space 44a from inlet 401 can be blown out directly from outlet 402a. When supply fan 42 is ON (in mechanical air supply mode), conditioned air that flows into front space 44a from inlet 401 is drawn into back space 44b via passage 403, allowing conditioned air to be blown out at an increased volume from outlet 402b. This reduces pressure loss in natural air supply mode.

[0032] (Operation of the air supply device) 5 is a flowchart showing the processing executed by supply air control unit 46. For ease of understanding, the description will be given here assuming that room 101 to be air-conditioned is living room 101L (FIG. 1).

[0033] As shown in Fig. 5, supply air control unit 46 compares the room temperature detected by temperature sensor 36 installed in living room 101L with the set temperature, and determines whether the detected room temperature, i.e., the current room temperature of living room 101L, satisfies a predetermined temperature condition (step S1). Specifically, supply air control unit 46 determines whether the temperature (temperature difference) obtained by subtracting the set temperature from the detected room temperature is less than, for example, 1 degree (predetermined temperature). If the temperature difference is less than 1 degree, it is considered that living room 101L is being cooled effectively, and supply air fan 42 is turned off (step S5). This causes discharge air volume variable device 40 to operate in natural air supply mode.

[0034] On the other hand, if it is determined that the temperature difference is 1 degree or more and thus satisfies the predetermined room temperature condition, supply air control unit 46 determines whether this room temperature condition has continued for, for example, 30 minutes (predetermined time) or more (step S2). If the predetermined room temperature condition has continued for less than 30 minutes, supply air fan 42 remains OFF (step S5). If the predetermined room temperature condition has continued for 30 minutes or more, supply air fan 42 is turned ON (step S3). This causes blowout air volume variable device 40 to operate in mechanical air supply mode. In this way, by controlling the operation of supply air fan 42 in consideration of changes in room temperature, hunting can be prevented.

[0035] It is desirable that the intake air fan 42 be turned on only when the opening degree of the damper 35 is 100% (fully open) (step S4). In other words, it is desirable that the intake air control unit 46 stop the intake air fan 42 when the opening degree of the damper 35 is less than a predetermined opening degree (100%), regardless of the above-mentioned room temperature conditions. In other words, it is desirable that the intake air fan 42 be operated only when cooling is not effective through adjustment by the damper 35. This makes it possible to sufficiently reduce power consumption. Note that information about the opening degree of the damper 35 can be obtained from the air conditioning control unit 11 of the ducted air conditioning system 10 via communication means or the like.

[0036] As described above, with the variable airflow device 40 according to this embodiment, the supply air fan 42 is operated only when necessary, thereby reducing power consumption. Furthermore, by separating the air passage F1 in the natural air supply mode from the air passage F2 in the mechanical air supply mode, an increase in pressure loss in the natural air supply mode can be prevented despite the simple configuration.

[0037] Furthermore, variable discharge air volume device 40 can be retrofitted simply by connecting it to the downstream end of duct 34 of existing ducted air conditioning system 10. As described above, the on / off control of supply air fan 42 uses i) the room temperature of target room 101 detected by temperature sensor 36, ii) the opening degree of damper 35, and iii) the transition time of the room temperature, but i) temperature sensor 36 and ii) damper 35 are mounted on existing ducted air conditioning system 10. Therefore, there is no need to install additional sensors for on / off control of supply air fan 42. This makes it possible to easily and inexpensively compensate for insufficient air conditioning capacity of existing ducted air conditioning system 10.

[0038] In this embodiment, an example has been described in which the air conditioning control unit 11 of the duct-type air conditioning system 10 and the supply air control unit 46 of the variable airflow device 40 are provided independently, but these may also be realized by a common control device.

[0039] (Variation) 3 has a natural air supply outlet 402a and a mechanical air supply outlet 402b. In this case, when the air supply fan 42 is operating, there is a possibility that the conditioned air blown out from the mechanical air supply outlet 402b may flow back into the case 41 (front space 44a) through the natural air supply outlet 402a.

[0040] Therefore, as shown in FIG. 6, the outlet air volume variable device 40B may include, for example, a check valve 45 as a backflow prevention means capable of directly or indirectly closing the natural air outlet 402a.

[0041] Check valve 45 is in a nearly horizontal position when fully closed. Check valve 45 is normally in an open position and in an inclined position where inlet 401 side (duct 34 side) is higher than partition member 43 side. The inclined position is, for example, a position where the angle with respect to the horizontal plane is 40 to 60 degrees.

[0042] 6(A), the check valve 45 is open, and the conditioned air flowing in from the inlet 401 passes through a flow path below the check valve 45 in an inclined position (the flow path between the check valve 45 and the lower end of the side surface 411 of the case 41) and a flow path above the check valve 45 (the flow path between the check valve 45 and the partition member 43), and is then blown out from the outlet 402a. A small amount of conditioned air also passes through the passage 403 and is blown out from the other outlet 402b.

[0043] 6(B), check valve 45 is closed. This prevents conditioned air from flowing back into front space 44a from outlet 402a when supply fan 42 is operating. Note that check valve 45 may be opened or closed electrically or mechanically.

[0044] According to this modification, a backflow of conditioned air in the mechanical air supply mode can be prevented with a simple configuration, thereby effectively cooling and heating room 101. Note that the backflow prevention means is not limited to check valve 45.

[0045] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0046] 10 Ducted air conditioning system, 31 Air conditioner, 32 Blower fan, 33 Branch chamber, 34 Duct, 35 Damper, 36 Temperature sensor, 40, 40A, 40B Air volume variable device, 41 Case part, 42 Air supply fan, 43 Partition member, 45 Backflow prevention valve, 46 Air supply control part, 100 House, 101 Living room, 401 Inlet, 402, 402a, 402b Outlet, 403 Passage, F1 First air path, F2 Second air path.

Claims

1. A variable blowing air volume device applied to a ducted air conditioning system that supplies conditioned air from an air conditioner to a room through a duct, a case portion connected to a downstream end portion of the duct, the case portion having a first air passage extending from an inlet for conditioned air to a first outlet and a second air passage extending from the inlet to a second outlet; a supply fan that is disposed on the second air passage within the case portion and operates under predetermined conditions.

2. The variable blowing air volume device of claim 1, further comprising an air supply control unit that operates the air supply fan when the room temperature of the room satisfies a predetermined room temperature condition, and stops the air supply fan when the room temperature of the room does not satisfy the predetermined room temperature condition.

3. The blow-out air volume varying device according to claim 2 , wherein the supply air control section controls the supply air fan based on a room temperature detected by a temperature sensor used in the duct type air conditioning system.

4. The ducted air conditioning system has a damper for adjusting an opening degree of each of the ducts, The variable blow-out air volume device according to claim 2 , wherein the supply air control unit stops the supply air fan when an opening degree of the damper is less than a predetermined opening degree, regardless of the room temperature condition.

5. 2. The variable blow air volume device according to claim 1, further comprising a backflow prevention means for preventing the conditioned air blown out from said second blowing outlet from flowing back out from said first blowing outlet when said supply fan is in operation.

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