JP3732984B2 - Air conditioner - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an air conditioner including a plurality of outdoor units, and relates to operation control of each outdoor unit.
[0002]
[Prior art]
In general, an air conditioner is known in which a plurality of outdoor units are connected in parallel to an inter-unit pipe extending from the indoor unit, and the number of operating outdoor units is controlled in accordance with an air conditioning load. In order to prevent a specific outdoor unit from being operated at all times, for example, a priority order for driving is set in advance for each outdoor unit, and this type of unit is operated last time in the set order. The outdoor unit is excluded and the outdoor unit is operating.
[0003]
Alternatively, each outdoor unit is operated so that the accumulated operation time is leveled by paying attention only to the accumulated operation time of each outdoor unit.
[0004]
[Problems to be solved by the invention]
However, in the conventional configuration, the following problem occurs in the case of an air conditioner that drives a compressor using an internal combustion engine such as a gas engine.
[0005]
In general, the life of a starter that starts an engine depends on the number of engine starts. For this reason, if start-up is repeated frequently in a specific outdoor unit, the starter of this outdoor unit must be maintained faster than the starter maintenance of other equipment, and the maintenance time can be unified. As a result, there is a problem that maintenance costs are required.
[0006]
In addition, when a gas engine is used as the drive source, since there are many control parameters and operation is unstable compared to the case where an electric motor is used as the drive source, each outdoor unit is prone to malfunction. If it happens, it is necessary to stop the operation as soon as possible. For this reason, in an air conditioner using a gas engine, there is a problem that finer control is required to increase operating efficiency, and that conventional start / stop control alone is insufficient.
[0007]
Accordingly, an object of the present invention is to solve the problems of the above-described conventional technology, average the number of maintenance of each outdoor unit, perform finer start / stop control, and optimize the operating efficiency. To provide an apparatus.
[0008]
[Means for Solving the Problems]
According to the first aspect of the present invention, a plurality of outdoor units each having a compressor driven by a gas engine are connected in parallel to an inter-unit pipe extending from the indoor unit, and the plurality of outdoor units are operated in accordance with an air conditioning load. In the air conditioner for controlling the number of units, the means for accumulating the number of activations of each outdoor unit, the unit for accumulating the cumulative operation time of each outdoor unit, and the accumulated operation time when the number of operations is increased. means for activating a small outdoor unit preferentially, and wherein when the accumulated operation time of the outdoor units are equal, and means for activating preferentially less outdoor unit having accumulated the number of activations To do.
[0009]
In the first aspect of the invention, the cumulative operation time and the number of activations of each outdoor unit are integrated, the outdoor unit with a short cumulative operation time is preferentially activated, and the outdoor unit with a small activation frequency is preferentially activated. Therefore, the cumulative operation time and the number of activations of a specific outdoor unit do not increase. For this reason, for example, the operation time of each outdoor unit is leveled, the life of the starter of the engine that is the drive source is averaged, the maintenance time is unified, and the maintenance cost is reduced.
[0010]
The invention according to claim 2 is the invention according to claim 1, wherein the capacity of each outdoor unit is different, and when the cumulative operation time of each outdoor unit is equal when the number of operating units is increased, A means for starting an outdoor unit having a small capacity in preference to the number of activations is provided.
[0011]
In the invention according to claim 2, since the outdoor unit with a small capacity is activated with priority, for example, when the air conditioning load is extremely small, the outdoor unit with a capacity larger than necessary is not activated, and the necessary minimum Operation is performed with a limited capacity, and operation efficiency is improved.
[0014]
According to the third aspect of the present invention, a plurality of outdoor units each provided with a compressor driven by a gas engine are connected in parallel to an inter-unit pipe extending from the indoor unit, and the plurality of outdoor units are operated in accordance with an air conditioning load. in the air conditioning apparatus for controlling the number, and means for accumulating the number of activations of the respective outdoor units, means for accumulating the accumulated operation time of the outdoor units, when reducing the number of operating, often accumulated operation time integrating the outdoor unit is stopped, then, stops the small outdoor unit capacity, then, it is characterized in that a means for stopping the small outdoor unit of number of starts.
[0015]
In the invention according to claim 3, since the outdoor unit having a long accumulated operation time is stopped, the operation time of the outdoor unit is leveled. The outdoor unit with a small capacity is stopped next to the outdoor unit with a long cumulative operation time. Therefore, when the air conditioning load increases again and the number of outdoor units to be operated is increased, the unit with a small capacity is preferentially activated. Can do.
In addition, since the outdoor unit with a small number of activations is stopped after that, the air conditioning load increases after reducing the number of operating units, and when a new outdoor unit is activated, the outdoor unit with a large number of activations is activated without being activated. An outdoor unit with a low frequency starts. For this reason, the frequency | count of starting of a specific outdoor unit does not increase. Therefore, when an engine or the like by starting the starter is used as the drive source of the apparatus, the life of the starter is averaged, the maintenance timing is unified, and the maintenance cost is reduced.
[0016]
The invention according to claim 4 is the case of the invention according to claim 3, comprising means for judging the malfunction of the outdoor unit from the refrigerant pressure, the refrigerant temperature, the device rotation speed, etc., and there is a malfunctioning outdoor unit, In the case of reducing the number of operating units, there is provided a means for stopping the malfunctioning outdoor units in preference to the outdoor units having a long cumulative operation time .
[0017]
In the invention described in claim 4 , when the number of operating units is reduced, the malfunctioning outdoor unit is preferentially stopped, and therefore, for example, the refrigerant pressure and temperature are abnormally low compared to other outdoor units. When there is a malfunctioning outdoor unit that is increased or increased, the refrigerant does not flow into and out of the malfunctioning outdoor unit through the inter-unit piping. Therefore, the malfunction of a certain outdoor unit is not reflected in the entire apparatus, and the optimum operation is maintained.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
[0023]
In FIG. 1, 1a and 1b show outdoor units, and 3a and 3b show indoor units. The outdoor unit 1a includes an accumulator 10a, a compressor 11a driven by a gas engine, an oil separator 12a, a four-way valve 13a, an outdoor heat exchanger 14a, and an outdoor electric expansion valve 15a. Reference numeral 17a denotes a fan of the outdoor heat exchanger 14a. Since the outdoor unit 1b is the same as the outdoor unit 1a including the following configurations, the description thereof is omitted.
[0024]
The indoor unit 3a includes an indoor heat exchanger 34a and an indoor electric expansion valve 35a (hereinafter referred to as “indoor mechanical valve 35a”). Since the indoor unit 3b is the same as the indoor unit 3a including the following configuration, the description thereof is omitted. From the indoor units 3a and 3b, an inter-unit pipe consisting of a gas pipe 5 and a liquid pipe 7 extends, and outdoor units 1a and 1b are connected in parallel to the inter-unit pipe.
[0025]
The oil separator 12a separates the lubricating oil in the refrigerant discharged from the compressor 11a, and the separated lubricating oil is always returned to the compressor 11a through the oil return pipe 21a and the forced oil return pipe 22a. It is. The oil return pipe 21a is always provided with a capillary tube 24a, and flow resistance is applied to the oil returned to the compressor 11a by the capillary tube 24a. This constant oil return pipe 21a is connected to the middle of the oil separator 12a. As long as the oil level of the oil in the oil separator 12a exceeds the position where the oil separator 12a is connected, the oil always flows through the constant oil return pipe 21a. Returned to the suction pipe. The forced oil return pipe 22a is provided with opening / closing valves 23a and 25a. The forced oil return pipe 22a is connected to the bottom of the oil separator 12a, and the oil in the oil separator 12a is forcibly returned to the suction pipe of the compressor 11a by opening the on-off valves 23a and 25a.
[0026]
The forced oil return pipes 22 a and 22 b of the outdoor units 1 a and 1 b are connected by a balance pipe 51. The balance pipe 51 is connected between the oil separator 12a and the check valve 18a through the third auxiliary pipe 53a, and the third auxiliary pipe 53a is provided with a third on-off valve 55a.
[0027]
When the third on-off valve 55a is opened and the four-way valve 13a is switched to the position shown in the drawing, the balance pipe 51 communicates with the outdoor heat exchanger 14a.
[0028]
In the air conditioner configured as described above, in the present embodiment, the compressors 11a and 11b are driven by the gas engines 100a and 100b, respectively. The shafts 101a and 101b are led out from the main bodies of the compressors 11a and 11b, pulleys (not shown) are connected to the shafts 101a and 101b, and the outputs of the gas engines 100a and 100b via the pulley V belts 102a and 102b. The shafts are connected.
[0029]
In the above configuration, during the cooling operation, the refrigerant from the compressors 11a and 11b is supplied with oil separators 12a and 12b, four-way valves 13a and 13b, outdoor heat exchangers 14a and 14b, and outdoor electric motor as shown by solid arrows in FIG. Flows into the liquid pipe 7 through the expansion valves 15a and 15b, enters the respective indoor units 3a and 3b, flows in the order of the indoor electric expansion valves 35a and 35b, and the indoor heat exchangers 34a and 34b, and flows out into the gas pipe 5 Further, it is returned to the compressors 11a and 11b via the four-way valves 13a and 13b and the accumulators 10a and 10b.
[0030]
Further, during the heating operation, the refrigerant from the compressors 11a and 11b flows out to the gas pipe 5 through the oil separators 12a and 12b and the four-way valves 13a and 13b as shown by dotted arrows in FIG. 3a, 3b, the indoor heat exchangers 34a, 34b and the indoor electric expansion valves 35a, 35b in this order and out to the liquid pipe 7, and further the outdoor electric expansion valves 15a, 15b, the outdoor heat exchangers 14a, 14b. The four-way valves 13a and 13b and the accumulators 10a and 10b are returned to the compressors 11a and 11b.
[0031]
In this embodiment, the order of starting and stopping the outdoor units 1a and 1b is controlled so that any specific outdoor unit 1a or 1b is not always continuously operated. This rotation control is controlled by a centralized control device 16 that controls the outdoor units 1a and 1b in an integrated manner.
[0032]
As shown in FIG. 2, the central control device 16 includes a central processing unit 107. The central processing unit 107 includes a timer 109 for integrating the cumulative operation time of each outdoor unit 1a, 1b, and each outdoor unit. A counter 111 for integrating the number of activations of the units 1a, 1b and a memory 113 for storing the rated capacity of each outdoor unit 1a, 1b are connected. The rated capacity of the outdoor unit 1a is 7.46 kW (10 HP), and the rated capacity of the outdoor unit 1b is 14.92 kW (20 HP).
[0033]
As for the order of activation of the outdoor units 1a and 1b, first, those with a short accumulated operation time accumulated by the timer 109 are preferentially activated. When the accumulated operation time is equal, the one with the smaller rated capacity stored in the memory 113 is preferentially activated. When the rated capacities are equal, the one with the smaller number of activations counted by the counter 111 is activated with priority.
[0034]
Gas engines 100a and 100b are used to drive the compressor. Since the gas engines 100a and 100b are started by a starter (not shown), if the number of start / stop increases, the life of the starter is shortened and must be frequently maintained.
[0035]
In this embodiment, the outdoor unit 1 with a short cumulative operation time is preferentially activated, and the outdoor unit 1 with a small number of activations is preferentially activated. Therefore, the cumulative operation time and the number of activations of a specific outdoor unit 1 are There will be no more.
[0036]
Therefore, the operation time of each outdoor unit 1 is leveled, the life of the starters of the compressors 11a and 11b is averaged, the maintenance time is unified, and the maintenance cost is reduced.
[0037]
In addition, since the outdoor unit 1 having a small capacity is activated in preference to the number of activations, the outdoor unit 1 having a capacity larger than necessary is not activated when the air conditioning load is extremely small. Therefore, the operation is performed with the minimum necessary capacity, and the operation efficiency is improved. For example, when the operation starts with an initial air conditioning load of 4 kW, only the outdoor unit 1a having a rated capacity of 7.46 kW needs to be activated, and then the air conditioning load increases and the air conditioning load decreases to 7.46 kW. When it exceeds, the outdoor unit 1b having a rated capacity of 14.92 kW may be activated.
[0038]
Next, the order of stopping the outdoor units 1a and 1b will be described.
[0039]
In this embodiment, when there is a malfunctioning outdoor unit 1 in the order of stopping, the operation of the outdoor unit 1 is preferentially stopped. In order to detect this malfunction, the central processing unit 107 shown in FIG. 2 detects pressure sensors 117a and 117b for detecting the refrigerant pressure on the high pressure side and the refrigerant temperature on the high temperature side via the control lines 115a to 115n. Temperature sensors 119a and 119b that perform rotation speed sensors 121a and 121b that detect rotation of the outdoor heat exchanger fan are connected. When the detected pressure in the central processing unit 107 and the pressure sensors 117a and 117b is abnormally low or high, the detected temperature in the temperature sensors 119a and 119b is abnormally low or high, or the rotational speed sensor 121a. When the rotational speed of 121b is abnormally low or high, it is determined that the operation state of the corresponding outdoor unit 1 is not good.
[0040]
In this embodiment, when the number of operating units is reduced, the malfunctioning outdoor unit 1 is stopped in preference to the number of activations, so that the refrigerant flows out of the malfunctioning outdoor unit 1 to the other outdoor units 1 through the inter-unit piping. There is no entry. Therefore, the malfunction of a certain outdoor unit is not reflected in the entire apparatus, and the optimum operation state is maintained.
[0041]
In the order of stopping the rotation operation, after stopping the malfunctioning outdoor unit 1, the outdoor unit 1 with a long cumulative operation time is stopped, then the outdoor unit 1 with a small capacity is stopped, and finally the number of activations Control which stops few outdoor units 1 is performed.
[0042]
Even in this embodiment, when the malfunctioning outdoor unit is excluded, the outdoor unit with a long cumulative operation time is preferentially stopped, so that the operation time of the outdoor unit 1 is leveled.
[0043]
Next to this accumulated operation time, the capacity is determined, and the outdoor unit 1 having a small capacity is stopped. If it does in this way, when the air-conditioning load increases again and the number of operating units of the outdoor unit is increased, the outdoor unit 1 having a small capacity can be preferentially activated.
[0044]
As mentioned above, although this invention was demonstrated based on one Embodiment, it is clear that this invention is not limited to this.
[0045]
For example, in the above-described embodiment, the rated capacities of the two outdoor units 1a and 1b were 7.46 kW (10 HP) and 14.92 kW (20 HP), respectively. There are five types of capacity, such as 5.96 kW (8 HP), 9.69 kW (13 HP), 11.92 kW (16 HP), and the combination of the capacity of any three outdoor units 1 Also good.
[0046]
Further, the central control device 16 incorporates various timers 109 such as a timer 109 for accumulating the cumulative operation time of each outdoor unit 1a, 1b. These timers 109 are incorporated in each outdoor unit 1a, 1b. Alternatively, only the data from the timer 109 may be taken into the central control device 16. In this way, for example, in the order of stopping when there is an outdoor unit 1 that is out of operation, the information is sent to the central processing unit 107 via the substrate (not shown) of the outdoor unit 1. The central processing unit 107 can preferentially stop the malfunctioning outdoor unit 1.
[0047]
【The invention's effect】
The order of starting and stopping the outdoor units is determined based on the cumulative operating time, and the cumulative operating time is leveled by taking into account the number of startups, the rated capacity and the operating status. When using a starter engine, etc., the life of the starter of each outdoor unit can be averaged, the maintenance time can be standardized, and it is not necessary to maintain a specific outdoor unit frequently, thus reducing maintenance costs. be able to.
[0048]
Since it is started from an outdoor unit with a small rated capacity according to the air conditioning load, the optimum operation efficiency is maintained even with an extremely low air conditioning load.
[0049]
When stopping the operation of an outdoor unit, if there is a malfunctioning outdoor unit, the operation is stopped preferentially, so refrigerant with abnormal pressure or temperature from other outdoor units via other unit piping There is no flow into the unit. Therefore, the malfunction of a certain outdoor unit is not reflected in the entire apparatus, and the optimum operation state is maintained.
[Brief description of the drawings]
FIG. 1 is a refrigeration circuit diagram showing an example of an air conditioner according to the present invention.
FIG. 2 is a block diagram illustrating a centralized control device.
[Explanation of symbols]
1, 1a, 1b Outdoor unit 3a, 3b Indoor unit 16 Central control device 100a, 100b Gas engine 107 Central processing unit 109 Timer 111 Counter 113 Memory

Claims (4)

In an air conditioner for connecting a plurality of outdoor units each having a compressor driven by a gas engine in parallel to an inter-unit pipe extending from the indoor unit , and controlling the number of operating units of the plurality of outdoor units according to an air conditioning load. ,
Means for accumulating the number of activations of each outdoor unit;
Means for integrating the cumulative operation time of each outdoor unit;
When increasing the number of operating units, means for giving priority to starting outdoor units with a short accumulated operating time; and
Means for preferentially starting outdoor units with a reduced number of times of activation when the accumulated operation time of each outdoor unit is equal ;
An air conditioner comprising: Means for starting an outdoor unit having a small capacity in preference to the number of activations when the capacity of each outdoor unit is different and the cumulative operation time of each outdoor unit is equal when the number of operating units is increased. The air conditioning apparatus according to claim 1, further comprising: In an air conditioner for connecting a plurality of outdoor units each having a compressor driven by a gas engine in parallel to an inter-unit pipe extending from the indoor unit, and controlling the number of operating units of the plurality of outdoor units according to an air conditioning load. ,
Means for accumulating the number of activations of each outdoor unit;
Means for integrating the cumulative operation time of each outdoor unit;
In order to reduce the number of operating units, there is provided means for stopping outdoor units with a large cumulative accumulated operating time, then stopping outdoor units with a small capacity, and then stopping outdoor units with a small number of activations. An air conditioner characterized. When there is a malfunctioning outdoor unit based on the refrigerant pressure, refrigerant temperature, equipment rotation speed, etc., and there is a malfunctioning outdoor unit, when the number of units to be operated is reduced, priority is given to the outdoor unit with a long cumulative operation time. The air conditioner according to claim 3, further comprising means for stopping the malfunctioning outdoor unit .

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