JP2011144996A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner having a simple configuration capable of inhibiting blowing out of cold air even when at least one of a plurality of heat exchangers functions as an evaporator during heating operation. <P>SOLUTION: In the air conditioner 1, in an air course 5 in which air is made to flow via an air blower 3, the plurality of heat exchangers 4A, 4B, 4C are arranged in series in the direction across the air course 5, and outdoor units 7A, 7B, 7C including different independent refrigerant systems, respectively are connected with the heat exchangers 4A, 4B, 4C. Shut-off means 9A, 9B, 9C each capable of shutting off flowing of air are provided with respect to the plurality of heat exchangers 4A, 4B, 4C. Each of the shut-off means 9A, 9B, 9C can be operated independently. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an air conditioner that is applied to air conditioning in a large space called an air handling unit, which takes in indoor air and outside air and blows air to the air conditioned space through a duct after adjusting the temperature.

  Indoor air or outside air is introduced through a duct into the unit body where a heat exchanger, blower, air filter, and humidifier if necessary are installed, and heat exchange is performed between the air and the refrigerant. In an air conditioner called a large air handling unit that cools or heats the air and then sends the temperature-controlled air to each air-conditioned space through a duct, in the air passage of the unit body in a direction crossing the air passage There is known an air conditioner in which a plurality of heat exchangers arranged in series are installed, and an outdoor unit having a separate refrigerant system that is independent of each other is connected to the heat exchanger.

  In such an air conditioner, even when any of the outdoor units starts the defrost operation during the heating operation, the air blower is continuously operated without being stopped because the heating operation is continued as it is. As a result, the indoor heat exchanger connected to the outdoor unit that has started the defrost operation becomes an evaporator, and cold air is blown out or the blow-out temperature falls due to the operation of the indoor blower.

  Therefore, when one outdoor unit starts the defrost operation, the other outdoor unit is provided so that each of the indoor fans is provided corresponding to the plurality of indoor heat exchangers so that the plurality of outdoor units do not enter the defrost operation at the same time. The heating operation of the unit is forced to continue, and the indoor blower and compressor are controlled in accordance with the operation state of one unit, and the indoor blower of the unit on the side where the defrost operation is started is stopped or the light wind operation is performed to blow out cold air. Japanese Patent Application Laid-Open No. H10-228688 proposes an air conditioner that is suppressed.

Japanese Patent Laid-Open No. 10-9725

However, in the air conditioner disclosed in Patent Document 1, it is necessary to provide a plurality of indoor blowers corresponding to the plurality of indoor heat exchangers provided in one indoor unit main body. There was a problem that complication and cost increase were inevitable.
Moreover, even if the indoor blower on the unit side that is operating in defrost is stopped or operated in a breeze, it is difficult to prevent the cold air flowing through the evaporator from blowing out unless the ventilation path is partitioned. There was a problem that it was not possible to eliminate the blowout and the drop in the blowout temperature.

  The present invention has been made in view of such circumstances, and has a simple configuration capable of preventing the blowing of cold air even when at least one of a plurality of heat exchangers becomes an evaporator during heating operation. The purpose is to provide an air conditioner.

In order to solve the above problems, the air conditioner of the present invention employs the following means.
That is, an air conditioner according to the present invention includes a plurality of heat exchangers arranged in series in a direction crossing the air passage in an air passage through which air flows through the blower, and the heat exchanger In the air conditioner to which the outdoor unit having a separate refrigerant system is connected to each of the plurality of heat exchangers, each of the plurality of heat exchangers is provided with a blocking means capable of blocking the flow of air. The means are characterized in that each is independently operable.

  According to the present invention, the plurality of heat exchangers provided in the air passage through which the air is circulated through the blower is provided with the blocking means capable of blocking the flow of air. Are operated independently of each other. For example, even when a defrost operation or an oil return operation is performed during the heating operation, and any of the heat exchangers functions as an evaporator, the heat exchange is performed. By operating the shut-off means provided corresponding to the heat exchanger and shutting off the air flow to the heat exchanger, it is possible to prevent the cool air from blowing out from the heat exchanger. Accordingly, it is possible to minimize the blowout of cold air and the decrease in the blowout temperature, and to improve the feeling and the heating performance.

  Furthermore, the air conditioner of the present invention is characterized in that, in the above air conditioner, the blocking means is provided on the upstream side in the air flow direction with respect to the plurality of heat exchangers.

  According to the present invention, since the shut-off means is provided upstream of the plurality of heat exchangers in the air flow direction, any one of the heat exchangers functions as an evaporator during the heating operation. Even if it becomes, the state which air contacts and this heat exchanger can be eliminated. Therefore, the temperature drop of the warm air can be made small and the heating performance can be improved.

  Furthermore, the air conditioner of the present invention is any one of the above-described air conditioners, wherein the blocking means is constituted by a motor damper including a motor and a bumper that is driven by the motor and opens and closes the air flow path. It is characterized by.

  According to the present invention, the blocking means is constituted by a motor damper including a motor and a bumper that is driven by the motor and opens and closes the air flow path. Therefore, the motor damper is assembled to the surface of the heat exchanger integrally. It is possible to simply block the flow of air to the heat exchanger. As this motor damper, a general-purpose commercially available product can be used, and therefore the cost for providing the blocking means can be minimized.

  Furthermore, the air conditioner according to the present invention is configured such that, in any of the above-described air conditioners, the blower controls the blown air amount to be a target air amount when at least one of the blocking means is operated. It is characterized by that.

  According to the present invention, the blower is configured to control so that the blown air volume becomes the target air volume when at least one of the blocking means is operated, so that the pressure loss in the air passage increases due to the operation of the blocking means. Even if the blown air volume changes, the air volume can be increased or decreased by the blower to control the blown air volume to the target air volume. Therefore, the blown air volume can be kept at the target value, and the feeling and capability during heating can be ensured.

  Furthermore, the air conditioner according to the present invention is configured such that, in any of the above-described air conditioners, the outdoor unit controls the blowout temperature to be a target temperature when at least one of the blocking means is operated. It is characterized by being.

  According to the present invention, since the outdoor unit is configured to control the blowout temperature to be the target temperature when at least one of the blocking means is operated, the pressure loss in the air passage is reduced by the operation of the blocking means. Even if the air volume changes and the blowout temperature changes accordingly, it is possible to control the blowout temperature to the target temperature by increasing or decreasing the rotation speed of the compressor by each outdoor unit. Therefore, the blowing temperature can be kept at the target value, and the feeling and capability during heating can be ensured.

  According to the present invention, even if a defrost operation or an oil return operation is performed during the heating operation, and any one of the heat exchangers functions as an evaporator, the interruption provided for the heat exchanger is provided. By operating the means and shutting off the flow of air to the heat exchanger, it is possible to prevent the blowing of cold air from the heat exchanger, so that the blowing of cold air and the decrease in the blowing temperature are minimized. It is possible to improve the feeling and the heating performance.

It is a block diagram of the air conditioner which concerns on one Embodiment of this invention. It is the side view (A) of the open state of the motor damper integrated in the air conditioner of FIG. 1, and the side view (B) of a closed state. It is a control flowchart of the motor damper incorporated in the air conditioner of FIG.

Embodiments according to the present invention will be described below with reference to FIGS. 1 to 3.
FIG. 1 shows a configuration diagram of an air conditioner according to an embodiment of the present invention. FIG. 2 shows a side view (A) of a motor damper incorporated in the air conditioner and a side view of a closed state ( B) is shown.
The air conditioner 1 includes a unit main body 2 in which an indoor blower 3 and a plurality of heat exchangers 4A, 4B, and 4C are provided. The plurality of heat exchangers 4 </ b> A, 4 </ b> B, 4 </ b> C are arranged in series in the air passage 5 in the unit body 2 in a direction crossing the air passage 5.

  Inside the unit body 2, indoor air and / or outside air is sucked through a duct (not shown), and the air is cooled or heated by the heat exchangers 4A, 4B, and 4C to cool air or warm air. There is no wind, and air is sent to each air-conditioned space through a duct (not shown). Further, an indoor controller 6 is provided in the unit main body 2 and detects the blowout temperature T and the blown air volume (pressure) P, and is installed in the rotational speed of the indoor blower 3 and outdoor units 7A, 7B, and 7C described later. The blowing temperature T and the blowing air volume (pressure) P are controlled to the target temperature Te and the target air volume (pressure) Pe by increasing or decreasing the rotational speed of the compressor (not shown).

  In the unit body 2, an air filter is provided on the air suction side of the air passage 5, and a humidifier or the like may be provided on the downstream side of the heat exchangers 4A, 4B, 4C as necessary. These are not shown in the figure.

  Outdoor units 7A, 7B, 7C each having a separate independent refrigerant system are connected to the plurality of heat exchangers 4A, 4B, 4C via refrigerant pipes and communication lines 8A, 8B, 8C, etc. . Each outdoor unit 7A, 7B, 7C includes, as is known, a compressor that compresses refrigerant, a four-way switching valve that switches the circulation direction of the refrigerant to a cooling cycle or a heating cycle, an outdoor air heat exchanger that condenses or evaporates the refrigerant, The outdoor air heat exchanger is provided with an outdoor fan that circulates outside air, an outdoor controller, and the like.

  Further, in the unit body 2, on the upstream surface in the air flow direction of the heat exchangers 4A, 4B, 4C, blocking means (motor damper) 9A capable of blocking the air flow to the heat exchangers 4A, 4B, 4C. , 9B, 9C are installed. For the blocking means 9A, 9B, 9C, for example, commercially available general-purpose motor dampers MD1, MD2, MD3 can be used. The motor dampers MD1, MD2, MD3 can be assembled and integrated on the front surface of the heat exchangers 4A, 4B, 4C, and incorporated in the unit body 2.

  As shown in FIGS. 2A and 2B, the motor dampers MD1, MD2, and MD3 include a rectangular cylindrical frame 10, and three pieces in the vertical direction in the cylindrical frame 10 are provided. Butterfly dampers 11A, 11B, and 11C are rotatably installed via rotating shafts 12A, 12B, and 12C, and are synchronized via a link mechanism 14 by a motor 13 provided outside the cylindrical frame 10. It is configured to be rotated. 2A shows a state in which the butterfly dampers 11A, 11B, and 11C are rotated to the horizontal state and the air flow path is opened, and FIG. 2B shows the butterfly dampers 11A, 11B, 11C is turned to a vertical state, and the air flow path is blocked.

The motor dampers MD1, MD2, MD3 are controlled to open and close as follows.
While the heat exchangers 4A, 4B, and 4C function as evaporators and the cooling operation is performed, the motor dampers MD1, MD2, and MD3 are always open. On the other hand, the heat exchangers 4A, 4B, and 4C function as condensers and are open during normal operation even during heating operation. However, if the outdoor temperature is low during the heating operation, frost may be formed on the outdoor air heat exchangers on the outdoor units 7A, 7B, and 7C side. If frost accumulates on the outdoor air heat exchanger, the heat exchange is hindered and the heating capacity is reduced. Therefore, the heating operation is interrupted and the refrigerant circuit is switched to the cooling cycle to perform the nedefrost operation. In this case, the indoor heat exchangers 4A, 4B, and 4C function as an evaporator.

  Similarly, when the air conditioner 1 is in operation, if the lubricating oil in the compressor flows out to the refrigerant circuit side together with the refrigerant and the amount of the lubricating oil decreases, the compressor may cause poor lubrication. Therefore, in order to eliminate the shortage of lubricating oil in the compressor, the oil return operation is performed periodically or by detecting the outflow amount of the lubricating oil. Since the oil return operation is performed in the cooling cycle, the refrigerant circuit is switched to the cooling cycle even when the oil return operation is performed during the heating operation. Therefore, also in this case, the indoor heat exchangers 4A, 4B, and 4C function as an evaporator.

  As described above, when the indoor heat exchangers 4A, 4B, and 4C function as an evaporator during the heating operation, the cold air blows out from the heat exchangers 4A, 4B, and 4C in the air-conditioned space even during the heating operation. The cold air blows out or the temperature of the hot air is lowered. Therefore, in order to prevent such cold air blowout and temperature drop of the blowout air, a shutoff means capable of shutting off the air flow to the heat exchangers 4A, 4B, 4C on the upstream surface of the heat exchangers 4A, 4B, 4C. 9A, 9B, 9C are provided, and when any of the plurality of refrigerant systems starts defrost operation (or oil return operation), upstream of any of the corresponding heat exchangers 4A, 4B, 4C of the refrigerant system The shut-off means 9A, 9B, 9C (motor dampers MD1, MD2, MD3) provided on the side surface are operated in the state shown in FIG. 2 (B), and air circulation to the heat exchangers 4A, 4B, 4C is performed. I try to block it.

  That is, as shown in FIG. 3, during normal heating operation, the outdoor air heat exchanger of any refrigerant system detects that there is a need for defrost or that any refrigerant system requires an oil return operation. If so, the defrost operation (or oil return operation) is started as in step S1. Thereby, in step S2, for example, the motor damper MD1 is shut off. When the motor damper MD1 is shut off, the blowout temperature T and the blown air volume (pressure) P change. Therefore, in step S3, whether or not the detected value P of the blown air volume (pressure) is the target air volume (pressure) Pe. Determine. Here, if P ≠ Pe, in step S4, the motor rotation speed of the indoor blower 3 is increased or decreased to control P = Pe.

  Further, when the rotational speed of the indoor blower 3 is increased or decreased to change the air volume, the blowout temperature T changes accordingly. Therefore, when P = Pe in Step S3, the process proceeds to Step S5, and the detected value T of the blowout temperature. Determines whether or not the target temperature Te is reached. Here, if T ≠ Te, the process proceeds to step S6, and the compressor rotational speed of the unit that continues the heating operation in the outdoor units 7A, 7B, 7C is increased or decreased, and control is performed so that T = Te. To do. As a result, the blowing temperature T and the blowing air volume (pressure) P can be controlled to the target temperature Te and the target air volume Pe, respectively, regardless of the opening / closing operation of the motor dampers MD1, MD2, MD3.

With the configuration described above, according to the present embodiment, the following operational effects can be obtained.
During the cooling operation, the indoor heat exchangers 4A, 4B, and 4C function as an evaporator. In these evaporators 4A, 4B, and 4C, the air that is sucked into the unit main body 2 via the indoor blower 3 and flows through the air passage 5 and the low-temperature gas-liquid two-phase refrigerant are heat-exchanged. As a result, the cooled air is blown to the respective air-conditioned spaces via the ducts and supplied for cooling.

  Further, during the heating operation, the heat exchangers 4A, 4B, and 4C function as condensers. In these condensers 4A, 4B, and 4C, the air that is sucked into the unit main body 2 through the indoor blower 3 and flows through the air passage 5 and the high-temperature refrigerant gas are subjected to heat exchange. Thereby, the heated air is blown into each air-conditioned space through the duct and is used for heating. If any of the three refrigerant systems starts the defrost operation or the oil return operation during the heating operation, the heat exchangers 4A, 4B, and 4C of the refrigerant system function as an evaporator as described above. It becomes.

  Therefore, in the present embodiment, the motor dampers MD1, MD2 which are the blocking means 9A, 9B, 9C provided on the upstream side of the heat exchangers 4A, 4B, 4C corresponding to the refrigerant system that has started the defrost operation or the oil return operation. , MD3 is operated to block the air flowing through the heat exchangers 4A, 4B, 4C. As a result, it is possible to prevent cold air from blowing out from the heat exchangers 4A, 4B, and 4C. For this reason, it is possible to minimize the blowout of cold air and the decrease in the blowout temperature, and to improve the feeling and the air conditioning performance.

  Further, in the present embodiment, the motor dampers MD1, MD2, MD3 constituting the blocking means 9A, 9B, 9C are provided on the upstream side in the air flow direction with respect to the heat exchangers 4A, 4B, 4C, respectively. Even when any of the heat exchangers 4A, 4B, 4C functions as an evaporator during the heating operation, the state in which air flows in contact with the heat exchangers 4A, 4B, 4C can be eliminated. it can. Thereby, the temperature drop of the warm air can be made minute and the heating performance can be improved.

  The motor dampers MD1, MD2, and MD3 are configured by a general-purpose motor damper that includes a motor 13 and a plurality of butterfly bumpers 11A, 11B, and 11C that are rotated by the motor 13 to open and close the air flow path. By assembling the motor dampers MD1, MD2 and MD3 integrally on the surfaces of the heat exchangers 4A, 4B and 4C, it is possible to easily block the air flow to the heat exchangers 4A, 4B and 4C. The motor dampers MD1, MD2, MD3 may be general-purpose commercially available products, and therefore the cost for providing the blocking means 9A, 9B, 9C can be minimized.

  Further, when at least one of the shut-off means 9A, 9B, 9C is operated by the defrost operation or the oil return operation, the blown air volume (pressure) P or the blowout temperature T changes, but the blown air volume (pressure) P and the blowout temperature T Is detected, and the rotation speed of the indoor blower 3 and the rotation speed of the compressor are controlled so that the blown air volume (pressure) P and the blowout temperature T become the target air volume (pressure) Pe and the target temperature Te. Therefore, the blown air volume (pressure) P and the blown temperature T are kept at the target values Pe and Te, and the feeling and capability during heating can be ensured.

  In addition, this invention is not limited to the invention concerning the said embodiment, In the range which does not deviate from the summary, it can change suitably. For example, in the above-described embodiment, the outdoor units 7A, 7B, and 7C provided corresponding to the heat exchangers 4A, 4B, and 4C have a unit configuration in which two units are connected in parallel. It is good also as a structure which isolate | separated the refrigerant | coolant flow path in each heat exchanger 4A, 4B, 4C into several systems according to top and bottom.

  Moreover, in the said embodiment, the blowing air volume (pressure) P and the blowing temperature T are detected, and the rotation speed of the indoor air blower 3 and the rotation speed of a compressor are set so that it may become the target air volume (pressure) Pe and the target temperature Te. In addition to this, for example, according to the number of motor dampers MD1, MD2 and MD3, for example, the rotational speed of the indoor blower 3 and the rotation of the compressor are stepwise by a predetermined rotational speed. The number may be changed.

DESCRIPTION OF SYMBOLS 1 Air conditioner 2 Unit main body 3 Indoor fan 4A, 4B, 4C Heat exchanger 5 Air path 7A, 7B, 7C Outdoor unit 9A, 9B, 9C Shut off means (motor damper MD1, MD2, MD3)
DESCRIPTION OF SYMBOLS 10 Cylindrical frame 11A, 11B, 11C Butterfly damper 12A, 12B, 12C Rotating shaft 13 Motor 14 Link mechanism

Claims (5)

A plurality of heat exchangers arranged in series in a direction crossing the air passage in an air passage through which air is circulated through the blower, and separate refrigerants that are independent of the heat exchanger. In an air conditioner to which an outdoor unit having a system is connected,
An air conditioner characterized in that the plurality of heat exchangers are each provided with blocking means capable of blocking the flow of air, and the blocking means can be independently operated.   2. The air conditioner according to claim 1, wherein the blocking unit is provided upstream of the plurality of heat exchangers in an air flow direction.   3. The air conditioner according to claim 1, wherein the blocking unit is configured by a motor damper including a motor and a bumper that is driven by the motor and opens and closes an air flow path. 4.   The air conditioner according to any one of claims 1 to 3, wherein the blower is configured to control the blown air volume to a target air volume when at least one of the blocking means is operated. . The air conditioning according to any one of claims 1 to 4, wherein the outdoor unit is configured to control the blowout temperature to be a target temperature when at least one of the blocking means is operated. Machine.

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