JPS62242749A - Air-conditioning machine - Google Patents

Abstract

PURPOSE:To treat atmospheric air through a common duct and obtain an air-conditioning machine suitable for a case in which a total heat exchanger is employed by a method wherein a pressure difference between the upstream side and the downstream side of the air discharging side of the total heat exchanger is detected by a pressure difference detector while the opening degree of an air circulation damper is controlled by a controller so that the pressure difference between the upstream side and the downstream side of the total heat exchanger is kept in a value higher than some value at all times. CONSTITUTION:In a duct connecting type air-conditioning machine, a pressure difference detector 11, detecting a pressure difference between the upstream side and the downstream side of a total heat exchanger 6 located in an air discharging duct, is provided and the opening and closing degree of an air circulation duct 2 is controlled in accordance with the detected pressure difference. In case a static pressure in the air discharging duct 9 is fluctuated, the pressure difference between the upstream side and the downstream side of the total heat exchanger 6 or the pressure difference between a static pressure in the air discharging duct 9 and a static pressure in the upstream side of the air circulation damper 2 is detected by employing the pressure difference detector 11. The air circulation damper 2 is controlled by a controller 12 so as to keep the pressure difference in a value higher than a given value at all times whereby stabilized atmosphere intake may be effected and the surge back of discharging air may be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a type of air conditioner that connects ducts.

BACKGROUND OF THE INVENTION Generally, an air conditioner incorporating a total heat exchanger is equipped with a ventilation fan 19 for introducing indoor air, as shown in FIG.
In the air path of this introduced air (ventilation) A2, ventilation A2
A circulating air damper 2o is provided to separate the air into exhaust C2 and circulating air. The air path of the exhaust gas C2 is provided with an exhaust damper 26 that blocks the air path when the operation is stopped, and a total heat exchanger 24 that recovers the heat amount of the exhaust gas C2 when the outside air D2 is taken in. Note that the air path of the exhaust gas C2 communicates with an exhaust duct 27 that is shared with other air conditioners.

The air path of the outside air D2 is provided with a total heat exchanger 24 and an outside air damper 26 that blocks the air path when the operation is stopped. Note that an outside air duct 28 that is shared with other air conditioners is connected to the air path of the outside air D2. In the air path of the air (supply air) B2 where the outside air D2 and the circulating air are combined, there is a filter 21 that removes dust from the air, a hot and cold water coil 22 that heats or cools the air, and a filter 21 that carries the supply air B2 indoors. A supply fan 23 for sending out air is provided. and outside air D2
The amount introduced was as follows.

When reducing the amount of outside air introduced, the circulating air damper 20 is opened, and the open/closed states of the exhaust damper 25 and the outside air damper 26 are adjusted according to the amount of outside air introduced.

Next, when increasing the amount of outside air introduced, use the circulating air damper 2o.
The exhaust damper 26 and the outside air damper 26 are opened in accordance with the amount of outside air introduced.

Problems to be Solved by the Invention However, in the conventional example, when a number of air conditioners are used at the same time, the exhaust duct 27 as shown in FIG.
Since the outside air duct 28 is shared with other air conditioners, the static pressure within the duct fluctuates depending on the operating state of the other air conditioners. Since the exhaust amount is determined by the pressure difference between the static pressure in front of the circulating air damper 2o and the static pressure in the exhaust duct 27, the exhaust amount also fluctuates.

Therefore, when the static pressure in the exhaust duct 27 becomes larger than the static pressure in front of the circulating air damper 2o, there is a problem in that the exhaust gas from other air conditioners flows backwards.

One way to solve this problem is to set the amount of outside air introduced higher than necessary, but this method requires extra energy and is therefore uneconomical.

Therefore, the present invention takes into account the above conventional problems and aims to provide an air conditioner suitable for treating outside air through a common duct and using a total heat exchanger. .

Means for Solving the Problems In order to achieve this object, the air conditioner of the present invention is a duct connection type air conditioner, in which the differential pressure before and after the total heat exchanger in the exhaust air path is reduced. A differential pressure detector is installed to detect
The configuration is such that the opening/closing degree of the circulating air damper is controlled according to the detected differential pressure.

With this configuration, when the static pressure in the exhaust duct fluctuates, the differential pressure across the total heat exchanger, that is, the difference between the static pressure in the exhaust duct and the static pressure in front of the circulating air damper, is detected by the differential pressure detector. This system detects the pressure difference using a pressure sensor, and controls the circulating air duplex with a control device so that the differential pressure is always kept above a certain value, thereby providing a stable intake of outside air and preventing backflow of exhaust gas. .

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows the configuration of an air conditioner according to an embodiment of the present invention, and FIG. 2 shows the state of air in each part depending on the opening degree of a circulating air damper in the same embodiment.

In FIG. 1, 1 is a ventilation fan that introduces indoor air, and the introduced air (ventilation) A1 is divided by a circulating air damper 2 into exhaust C1 and circulating air. The relation is a control device 12 that controls the opening/closing degree of the circulating air damper 2 in response to a signal from a differential pressure detector 11 that detects the differential pressure before and after the total heat exchanger 6 on the side.

An exhaust damper 7 and a total heat exchanger 6 are provided in the air path of the exhaust gas C1.
and a differential pressure detector 11, and the end is connected to an exhaust duct 9.
It leads to

The outside air D1 air path is provided with an outside air duct 10, a total heat exchanger 6, and an outside air damper 8, and joins the circulating air at the circulating air damper 2. This combined air (supply air) B,
A filter 3, a cold/hot water coil 4, and an air supply fan 5 are provided in the air path, and the air is sent into the room.

Based on FIG. 2, the state of the air in each part and the operation depending on the opening degree of the circulating air damper 2 will be explained.

The difference between the static pressure 13 in the exhaust duct 9 and the static pressure 14 in front of the circulating air damper 2 changes by opening and closing the circulating air damper 2. This differential pressure is equal to the differential pressure across the total heat exchanger,
An air volume proportional to the magnitude of this pressure difference across the front and back is generated, and this becomes an exhaust air volume of 16.

At this time, since the air supply fan 6 is controlled to maintain the air supply air volume 16 at the set value, the exhaust air volume 15 and the circulating air volume 17 are determined by the opening degree of the circulating air damper 2. 18 indicates the opening of the circulating air damper 2 when the static pressure 14 in front of the circulating air damper 2 is lower than the static pressure 13 in the exhaust duct) X9, that is, when the differential pressure across the total heat exchanger 6 is negative. This is a backflow region of the exhaust gas C1 that occurs as the temperature increases. However, in this embodiment, the opening degree of the circulating air damper 2 is controlled by the differential pressure detector 11 and the control device 12 so as to keep the differential pressure across the total heat exchanger 6 above a certain positive value. This prevents the backflow region 18 from occurring and prevents the exhaust gas C1 from flowing back. Further, since there is no need to set the amount of outside air introduced above the required amount, no extra energy is required.

Effects of the Invention As is clear from the explanation of the embodiments described above, the present invention detects the differential pressure across the total heat exchanger using a differential pressure detector, and maintains this differential pressure across the entire heat exchanger at a constant positive value. The circulating air damper is controlled by the control device to maintain the above level. This prevents exhaust from flowing backwards from the exhaust duct, and
There is also an energy saving effect as there is no need to set the amount of outside air introduced above the required amount. In this manner, the present invention realizes an excellent air conditioner with great practical effects.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the configuration of an air conditioner according to an embodiment of the present invention, FIG. 2 is a diagram showing the state of air in each part depending on the opening degree of the circulating air damper in the same embodiment, and FIG. It is a block diagram of an air conditioner. 1...Ventilation fan, 2...Circulating air damper, 6...Air supply fan, 6...Total heat exchanger, 11...・Differential pressure detector, 12...
Control device. Name of agent: Patent attorney Toshio Nakao and 1 other person5-
Jt Min Rahuan - Ichikin! If -4fx#Output f2--Ichiban υ device Fig. 2 Fig. 3

Claims (1)

[Claims] A ventilation fan for introducing indoor air, a circulating air damper for distributing this introduced air into exhaust air and circulating air,
an air supply fan that mixes the circulating air that has passed through the circulating air damper and outdoor air and supplies the mixture indoors; an exhaust duct that discharges the exhaust gas outdoors in common with another air conditioner main body;
An outside air duct that supplies the outside air from outside in common with other air conditioner main bodies, and a total heat exchanger installed in the passage between the exhaust air and the outside air, and a differential pressure across the exhaust side of the total heat exchanger. An air conditioner configured to detect the pressure difference with a differential pressure detector, and control the opening degree of the circulating air damper so that the differential pressure across the total heat exchanger is always maintained above a certain value by a control device.