JP2007033006A - Outside air intake facility - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an operation control mechanism capable of attaining an energy saving operation for a fan, without disturbing the balance between air supply and exhaust in a room even when requirement for ventilation is changed. <P>SOLUTION: This outside air intake facility 1 comprises the fan 3 for taking outside air in, a main duct 4 with the flowing ventilation air Q2 taken in by the fan 3, a branch duct 5 branched from the main duct 4 to supply the ventilation air to the plurality of rooms, a bypass 6 for connecting the main duct 4 with an outside, and a damper 7 for opening an air duct of the bypass 6 when static pressure of the main duct 4 gets high, and for closing it when getting low. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an outside air intake facility for ventilating a plurality of rooms. More specifically, the present invention relates to an outside air intake facility that adjusts a supply amount in accordance with a request for ventilation from a plurality of rooms such as a hospital.

  Conventionally, a ventilation facility as shown in FIG. 4 has been used to ventilate a building such as a hospital having a large number of rooms. This ventilation facility 100 takes in outside air from the outside air intake 101 and blows the outside air at a constant air volume, a main duct 104 connected to the fan 102 via an air volume adjusting damper 103, and the main duct. A branch duct 105 is provided that branches from 104 and distributes ventilation air to each room. The branch duct 105 includes a total heat exchanger 106 for exchanging heat between the ventilation air supplied to each room and the air exhausted from the room, and the total heat exchanger 106 and the main duct 104. And a motor damper 107 that opens and closes the communication state.

  In such a conventional ventilation system 100, when a resident in each room turns on the power switch SW of the total heat exchanger 106, the total heat exchanger 106 is activated and the motor damper 107 is opened. Therefore, the outside air taken in from the fan 102 is flowed to the total heat exchanger 106 and is heat-exchanged with the air exhausted from the room, and then supplied into the room.

  Ventilation equipment is intended for ventilation, unlike air-conditioning equipment that adjusts room temperature or humidity. For this reason, it is sufficient for the ventilation fan 102 to have a capacity sufficient to satisfy the ventilation requirements of all rooms. Therefore, the air volume is not adjusted, and the air volume is constant. Rather, for stable air conditioning, it is desirable to supply a predetermined amount of ventilation air to each room.

In the conventional ventilation facility 100, when ventilation air is supplied to all the rooms, the ventilation air blown from the fan 102 is supplied to each room in a well-balanced manner. However, when the number of rooms requiring ventilation decreases, the static pressure of the ventilation air in the main duct 104 increases, and the balance between the ventilation air supplied from the fan 102 and the air exhausted from each room is lost.
Therefore, when the static pressure of the main duct is high (the number of rooms requiring ventilation is small), the ventilation air supplied into each room is more than the predetermined amount, and the air in the room is increased by that amount. Leaks into corridors. The discharged air moves to another room through a corridor or the like.

  In particular, when the ventilation facility 100 is used in a hospital, attention must be paid to such an imbalance. That is, it is preferable that the hospital room is not connected to other rooms as much as possible. For example, if a room is an infected patient room, it must be isolated from the other rooms. In this case, the above-described balance between supply and exhaust in the ventilation facility 100 becomes an infectious factor for other hospital rooms.

  Further, it is economically undesirable to operate the fan 102 in the same manner regardless of the amount of ventilation demand from each room.

  Therefore, an object of the present invention is to provide an outside air intake facility that does not disturb the balance between supply air and exhaust air in the room even when a change in ventilation requirements occurs. Furthermore, this invention makes it a subject to provide the external air intake equipment which can implement | achieve the energy saving driving | operation of a fan.

  An outside air intake facility according to the present invention (Claim 1) includes a fan for taking in outside air, a main duct through which ventilation air taken in by the fan flows, and supplying ventilation air to a plurality of rooms branched from the main duct. The bypass duct, the bypass communicating the main duct and the outside, and the bypass air passage are opened when the static pressure of the main duct is increased, and closed when it is lowered.

  In such an outside air intake facility, the bypass is preferably connected to the main duct between the branch duct closest to the fan and the fan (claim 2). Further, it is preferable that the damper comprises a blade provided rotatably in the bypass air passage and a weight that urges the blade by gravity in a direction in which the blade is closed. And a limit switch for detecting that the damper is opened more than a predetermined amount, and a control unit for stopping the operation of the fan for a predetermined time when the limit switch detects that the damper is opened more than a predetermined amount. (Claim 4).

  The outside air intake facility according to the present invention (Claim 1) is provided with a bypass through the main duct and outside air, and the bypass is provided with a damper that opens when the static pressure of the main duct is high and closes when it is low. Therefore, when the number of rooms requiring ventilation decreases, the static pressure of the ventilation air in the main duct rises, the damper opens, and part of the ventilation air is exhausted from the bypass. Thereby, the increase in the static pressure of the ventilation air flowing through the main duct can be prevented. On the other hand, when the number of rooms requiring ventilation increases and the static pressure of the ventilation air flowing through the main duct decreases, the damper closes and the static pressure increases. Therefore, even if the number of rooms requiring ventilation is increased or decreased, fluctuations in the static pressure of the ventilation air can be reduced. Therefore, the flow of air from the room toward the duct can be prevented by the fluctuations in the static pressure. Therefore, the movement of the room air between different rooms caused by the collapse of the air balance accompanying the change in the air supply amount to each room can be prevented, which is suitable for use in a hospital or the like.

  In such an outside air intake facility, when the bypass is connected to the main duct between the branch duct closest to the fan and the fan (Claim 2), the ventilation air is distributed to each room. The static pressure of ventilation air can be adjusted. For this reason, the balance between air supply and exhaust in the room is not further disturbed.

Further, when the damper is composed of a blade provided rotatably in the air passage of the bypass and a weight that is urged by gravity in a closing direction of the blade (Claim 3), the damper is in a vertically closed state. In the initial stage where the air exhausted from the bypass collides with the blades of the air and the state where the air exhausted from the bypass collides with the blades rotating to a certain angle, the latter has a larger static pressure. Need the power of. Therefore, the blades of the damper act so as to open wider as the static pressure of the ventilation air increases. That is, the higher the static pressure of the ventilation air, the more air can be exhausted from the bypass, so the fluctuation of the static pressure can be adjusted efficiently.
In addition, such a mechanism for preventing fluctuations in the static pressure of the ventilation air does not require a complicated mechanism, and further, since the weight of the weight is used, it can be realized without a power source for operating the damper. it can.

  And a limit switch that detects that the damper is opened more than a predetermined amount, and a control unit that stops the operation of the fan for a predetermined time when the limit switch detects that the damper is opened more than a predetermined amount. (Claim 4) Since the fan is operated intermittently when the number of rooms requiring ventilation becomes considerably small, energy is saved.

  Next, an embodiment of the outside air intake facility of the present invention will be described with reference to the drawings. FIG. 1 is a schematic piping diagram showing an embodiment of the outside air intake equipment of the present invention, FIG. 2 is an enlarged cross-sectional view of a main portion of the bypass portion of FIG. 1, and FIGS. 3a, 3b and 3c are closed states of check dampers, respectively. It is the schematic which shows a half open state and a full open state.

  The entire outside air intake facility of the present invention will be described with reference to the piping diagram of FIG. An outside air intake facility 1 shown in FIG. 1 includes a fan 3 that takes in outside air from an outside air inlet 2, a main duct 4 through which air flows from the fan 3, branches from the main duct 4, and extends to each room. The bypass duct 5 that distributes the air to each room, the bypass 6 that extends from the vicinity of the outlet of the fan 3 of the main duct 4 and communicates the outside with the main duct 4 at a bypass point B (point B in the figure), A check damper 7 is provided in the bypass 6 and opens and closes the air passage. The check damper 7 is attached in such a direction that allows air to pass from the main duct 4 side to the outside, but not reversely.

  As shown in FIG. 2, the check damper 7 is provided with a limit switch 8 for detecting the fully opened state. The output of the limit switch 8 is transmitted to the control unit 9 for controlling the operation / stop of the fan 3. An air volume adjusting damper 10 that adjusts the amount of air to be blown is disposed between the fan 3 and the bypass 6. The air volume adjusting damper 10 is adjusted in advance according to the number of rooms. In the middle of the branch duct 5, a total heat exchanger 11 for performing heat exchange between the air supplied to each room and the air exhausted from the room is interposed. A motor damper 12 is provided in front of the total heat exchanger 11 to operate the communication between the room and the main duct 4.

  The air whose air volume has been adjusted from the fan 3 by the air volume adjusting damper 10 is referred to as blower air Q1, and the air flowing from the blower air Q1 to the room side by the main duct 4 at the bypass point B is referred to as ventilation air Q2 and Assuming that the air flowing to the bypass air is Q3, the relationship is blown air Q1 = ventilation air Q2 + bypass air Q3.

  The outside air intake 2 is provided with a filter to prevent dust from entering the fan 3. The fan 3 is a blower that stably supplies a constant air volume, and a sirocco fan or the like is used. The main duct 4 and the branch duct 5 are made of a thin metal plate such as stainless steel or a galvanized steel plate, are formed in a rectangular or spiral shape, and have flexibility and elasticity. The number of branch ducts 5 branched from the main duct 4 is about 10 to 20, and preferably about 13 to 17 branches. One end of the bypass 6 communicates with the main duct 4 on the fan 3 side (bypass point B) from the branch duct 5, and the other end communicates with the outside air near the outside air inlet 2.

  The check damper 7 is provided in the middle of the bypass 6 as shown in FIG. As shown in FIG. 3, the check damper 7 has a plate-like blade 7a having a substantially cross-sectional shape of the bypass 6 and extends outward from the left and right ends of the blade 7a. The shaft 7b is pivotally supported, and a weight 7c provided near the lower end of the lever 7d fixed to the shaft 7b. The shaft 7b is provided above the center position in the vertical direction of the blade 7a. As a result, when the bypass air Q3 flows through the bypass 6 in the left direction of FIG. 2, the blade 7a rotates around the shaft 7b in the direction of arrow R (clockwise), and the air passage is opened. At this time, the weight 7c provided at the lower end of the blade becomes a resistance force that prevents the rotation in the arrow R direction due to its own weight, and the lower end of the blade 7a is urged so as to be directed vertically downward. Further, when air is about to flow in the right direction, the blade 7a is not rotated counterclockwise by a stopper (not shown).

The limit switch 8 is provided in a case of the check damper 7 or the like at a position where the upper end of the lever 7d can be touched when the lever 7d rotates a predetermined angle in the direction of arrow R.
The controller 9 controls the operation / stop of the fan 3 based on information on the opening / closing of the damper obtained from the limit switch 8. That is, when the limit switch 8 detects that the opening degree of the check damper 7 exceeds a predetermined angle, the fan 3 is stopped for a predetermined time. When the fan 3 stops, the static pressure of the main duct 4 decreases, the blades 7a of the check damper 7 hang down, and the bypass 6 is closed. When the predetermined time has elapsed, the operation is resumed. Such a control unit 9 is preferably provided integrally with the fan 3. The stop time of the control unit 9 can be adjusted according to the scale of the outside air intake facility 1.
In addition to the limit switch 8, a position sensor using magnetism or light can be used. In addition, a potentiometer is used for the shaft 7b, and a sensor for measuring the rotation amount can be used to accurately detect the opening degree of the blade 7a.

The total heat exchanger 11 exhausts the air in the room to the outside by a built-in fan by turning the power on and off with the indoor switch SW. As the total heat exchanger 11, for example, plate members in which a plurality of lattice-shaped hollow portions are formed in parallel to the plate surface direction are alternately stacked so that the directions of the lattice-shaped hollow portions are orthogonal to each other. Then, the air inside the room is exhausted to the outside through one of the lattice-shaped hollows, and the ventilation air Q2 from the main duct 4 is passed through the other lattice-shaped hollow inside orthogonal to the ventilation air. Heat exchange is performed between Q2 and room air. For the plate-like member in which such a hollow portion is formed, a material having high thermal conductivity such as an aluminum molded film is used. Furthermore, an air-to-air rotary total heat exchanger that rotates a cylindrical rotor element in which the hollow portion is disposed in the axial direction can also be used.
The motor damper 12 is opened when the switch SW of the total heat exchanger is turned on, allows the interior of the room to communicate with the main duct 4, and closes in conjunction with the off operation.

  Next, with reference to FIG. 1, how the outside air intake equipment 1 formed in this way operates will be described. When there is no request for ventilation air Q2 by a resident, the motor damper 12 is closed and the room and the main duct 4 are not in communication. When the occupant of the room turns on the switch SW of the total heat exchanger 11 to request the ventilation air Q2, the total heat exchanger 11 exhausts the air in the room. Further, in conjunction with the ON state of the switch SW, the motor damper 12 is opened, and the ventilation air Q2 flows into the total heat exchanger 11, exchanges heat with the air leaving the room, and then is supplied into the room. . When stopping the ventilation, if the switch SW is turned OFF, the motor damper 12 is closed and the exhaust of indoor air by the total heat exchanger 11 is also stopped.

  As described above, the operation of the ventilation is stopped and stopped for each room, but the fan 3 for taking in outside air stops the fan 3 and the normal operation that operates continuously with the air volume determined based on the total number of rooms. It is operated in two operating states, namely energy-saving operation that intermittently operates. Moreover, the code | symbol P demonstrated below shows the static pressure of ventilation air Q2 before branching (the part of V in a figure).

  The normal operation is a state in which ventilation air is flowing through 4 or 5 to 15 rooms as the number of rooms. In the normal operation, the check damper 7 is in a substantially closed state or in a state close to being almost closed (see FIG. 3a). That is, the static pressure P generated on the side of the ventilation air Q2 is not so large as to lift the weight 7c upward and rotate the blade 7a in the direction of arrow R. Therefore, the bypass air Q3 (≈0) hardly flows through the bypass 6, and all of the blown air Q1 (≈Q2) from the fan 3 flows into the main duct 4.

  On the other hand, when the number of rooms requiring the ventilation air Q2 is reduced to about 4 to 10 rooms, the static pressure P gradually increases. The weight 7c is lifted upward by the increased static pressure ΔP, and the blade 7a rotates in the direction of arrow R (see FIG. 3b). Then, the bypass air Q3 (≈Q1-Q2) flows through the bypass 6. As a result, the static pressure P is kept substantially constant. Therefore, even if the number of rooms requiring ventilation air Q2 changes suddenly, the static pressure P does not change greatly, so the balance between supply and exhaust in each room does not collapse, and the pressure difference between the room and the duct Will not occur. Therefore, movement of air between rooms through a corridor or the like can be prevented.

Next, the energy saving operation (intermittent operation) of the outside air intake facility 1 will be described. In the energy-saving operation, the ventilation air Q2 is supplied only to 0 to 3 or 4 rooms in terms of the number of rooms, and the number of rooms through which the ventilation air Q2 is supplied is further reduced from the state of the 4 to 10 rooms. In this state, the chuck damper 7 cannot withstand the static pressure P and is fully opened (see FIG. 3c). When the chuck damper 7 is fully opened, much of the blown air Q1 is exhausted as bypass air Q3.
The wasteful operation state of the fan 3 in which much of the blown air Q1 is exhausted is detected by the lever 7d of the chuck damper 7 touching the limit switch 8. The limit switch 8 transmits to the control unit 9 that the useless operation of the fan 3 has been detected. When the control unit 9 receives the signal of the limit switch 8, the fan 3 is stopped for a predetermined time. When the fan 3 stops, the check damper 7 is closed again (see FIG. 3a), and the lever 7d does not touch the limit switch 8. When the predetermined stop time has elapsed and the power is turned on, the operation of the fan 3 can be resumed.

  As described above, when the demand for the ventilation air Q2 from each room is small, the fan 3 is temporarily stopped, and the operation is resumed after a predetermined time has elapsed. By performing such intermittent operation of the fan 3, unnecessary operation of the fan 3 can be eliminated, so that energy saving is realized, and further, the static pressure P of the ventilation air Q2 is increased while realizing energy saving. Can be prevented. Such a control can be easily realized without a complicated control system.

  The place where the bypass 6 is disposed (bypass point B) may be provided near the center or near the tip of the main duct 4 far away from the fan 3. However, before the blown air Q1 is branched into each room, excess air is exhausted as bypass air Q3 via the bypass 6, and after the static pressure P is adjusted, the remaining air is used as ventilation air Q2. Distributing to the room makes it difficult for the balance between air supply and exhaust in each room to be lost.

  Further, the weight 7c of the chuck damper 7 can be changed in a timely manner so as to maintain a predetermined value of the static pressure P according to the ventilation equipment. For example, in the case of a ventilation facility where the blown air Q1 is small, since the number of rooms requiring ventilation is small, the change in the static pressure P is not so large. Therefore, the weight of the weight 7c can be reduced. In addition to changing the weight of the weight 7c, if the weight 7c is changed from the lower end of the lever 7d by a bar-like member, the lever may be used to apply a load to the rotation of the blade 7a. it can.

  In this embodiment, the weight 7c is used. However, a weight having a mechanism for receiving a predetermined static pressure P may be used instead. For example, a spring or rubber is used in place of the weight 7c, or a rubber member formed in a plate shape is disposed inside the bypass 6 so that the rubber bends as the static pressure P increases.

FIG. 1 is a schematic piping diagram showing an embodiment of the outside air intake facility of the present invention. 2 is an enlarged cross-sectional view of the main part of the bypass portion of FIG. 3a, 3b and 3c are schematic views showing the closed state, half-open state and full-open state of the check damper, respectively. FIG. 4 is a schematic piping diagram showing a conventional ventilation facility.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outside air intake equipment 2 Outside air inlet 3 Fan 4 Main duct 5 Branch duct 6 Bypass 7 Check damper 7a Blade 7b Shaft 7c Weight 7d Lever 8 Limit switch 9 Control part 10 Air volume adjustment damper 11 Total heat exchanger 12 Motor damper B Bypass point SW Switch P Static pressure V Measurement site Q1 of the static pressure P of the main duct before branching to each total heat exchanger Q1 Blowing air Q2 Ventilation air Q3 Bypass air

Claims (4)

With fans that take in the outside air,
A main duct through which the ventilation air taken in by the fan flows,
A branch duct branched from the main duct and supplying ventilation air to a plurality of rooms;
A bypass communicating the main duct with the outside;
An outside air intake facility that includes a damper that opens when the static pressure of the main duct increases and closes the bypass air passage.   The outside air intake facility according to claim 1, wherein the bypass is connected to a main duct between a branch duct closest to the fan and the fan. The damper is
A blade provided rotatably in the bypass air passage;
The outside air intake facility according to claim 1 or 2, comprising a weight that is urged by gravity in a direction to close the blade. A limit switch for detecting that the damper is opened more than a predetermined amount;
The outside air intake facility according to claim 1, 2 or 3, further comprising a control unit that stops the operation of the fan for a predetermined time when it is detected that the limit switch is opened more than a predetermined amount.