JP4624002B2 - Engine-driven air conditioner - Google Patents

Description

  The present invention relates to an engine-driven air conditioner that performs air-conditioning operation with variable capacity according to the air-conditioning load of each indoor unit.

Conventional engine-driven air conditioners use a refrigerant driven by an outdoor unit including a compressor driven by the driving force of the engine and an outdoor heat exchanger, and one or more indoor units including an indoor heat exchanger. Connected by piping, each of the indoor units, for example, based on the temperature difference between the indoor temperature detected by the indoor temperature sensor and the set temperature set in the operation unit of each indoor unit, The air conditioning load of the indoor unit was calculated, the air conditioning load was calculated by the outdoor unit, the total air conditioning load was calculated, and the engine was operated according to the total air conditioning load to perform the air conditioning operation. (For example, refer to Patent Document 1).
JP 09-236299 A

  However, in the conventional engine-driven air conditioner, since the air-conditioning operation is performed based on the air-conditioning load, the operation efficiency of the engine and the operation efficiency of the compressor driven by the driving force of the engine are each Thus, it was not possible to perform a stable operation at the rotation speed with the best operating efficiency, and it was not possible to perform an energy saving operation making full use of the COP (coefficient of performance) of the engine-driven air conditioner.

  Therefore, the present invention has been made to solve such problems, and further provides an engine-driven air conditioner that can perform air-conditioning operation that promotes energy-saving operation.

1st invention connects the outdoor unit provided with the compressor and outdoor heat exchanger which are driven with the driving force of an engine, and the 1 unit or several indoor unit provided with an indoor heat exchanger by refrigerant | coolant piping. In an engine-driven air conditioner that performs air conditioning operation with variable capacity according to the air conditioning load detected by the indoor unit, the air conditioning load is calculated based on a temperature sensor provided in the indoor unit, and the like. Based on the air conditioning load, the engine and the compressor are operated at a rotational speed at which the operating efficiency of the engine and the compressor is the best and within a predetermined capacity range of the air conditioning load.

According to a second aspect of the present invention, an outdoor unit including a compressor driven by an engine driving force and an outdoor heat exchanger and one or a plurality of indoor units including an indoor heat exchanger are connected by a refrigerant pipe. In an engine-driven air conditioner that performs air conditioning operation with variable capacity according to the air conditioning load detected by the indoor unit, the air conditioning load is calculated based on a temperature sensor provided in the indoor unit, and the like. Normal operating means for controlling the operation of the engine and the compressor at the rotational speed determined based on the air conditioning load, and the rotational speed at which the operating efficiency of both the engine and the compressor is the best, and the air conditioning load And an energy saving operation means for operating the engine and the compressor within a predetermined capacity range.

According to a third aspect of the present invention, the normal operation means and the energy saving operation means are operation means selected by operation of an operation unit that instructs operation of the engine-driven air conditioner.

The fourth invention is characterized in that the air conditioning load within the predetermined capacity range is 80% to 120% of the air conditioning load.

  According to the present invention, further energy saving can be achieved by performing the energy saving operation in which the air conditioning operation is performed at the rotation speed at which the operating efficiency of both the engine and the compressor is the best. Since the air conditioning load of each indoor unit is calculated and any one of the normal air conditioning operations in which the operation is performed can be selected by operation of the operation unit, the energy saving operation and the normal operation are arbitrarily selected. be able to. Further, by using the alternative refrigerant R410A having a large volume capacity per unit volume and low pressure loss, and by allowing the energy saving operation to be performed within a predetermined capacity range based on the air conditioning load, The effect of this energy saving operation can be further promoted without giving discomfort.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing an embodiment of an engine-driven air conditioner 100 to which an energy saving operation means of the present invention is applied.

  The engine-driven air conditioner 100 is configured, for example, by connecting one outdoor unit 1 and a plurality of indoor units 2a and 2b with an inter-unit pipe 3 including a gas pipe 3a and a liquid pipe 3b. An alternative refrigerant R410a having a high refrigerant capacity per volume and low pressure loss is circulated.

  The outdoor unit 1 is connected to an engine 10 that generates a driving force by burning fuel such as gas, and a compressor 11 that compresses and discharges the alternative refrigerant R410a to the engine 10 via a driving force transmission unit (not shown). A four-way valve 12 that reverses the circulation direction of the refrigerant, an outdoor heat exchanger 13 that performs heat exchange between the refrigerant and outside air, an outdoor expansion valve 14 that depressurizes the refrigerant, and the compressor 11. And an accumulator 15 that performs gas-liquid separation of the refrigerant that is sucked in is connected by a refrigerant pipe and stored.

  The indoor units 2a and 2b flow into the indoor heat exchangers 20a and 20b that exchange heat between the indoor air and the indoor air in which the indoor units 2a and 2b are installed, and the indoor units 2a and 2b. Indoor expansion valves 21a and 21b for controlling the refrigerant amount of the refrigerant are respectively connected and accommodated by refrigerant pipes.

  Further, the engine-driven air conditioner 100 includes a control device 30 that performs operation control of the engine-driven air conditioner 100 and an operation unit 40 that performs operations such as operation instructions of the control device 30. Yes. The operation unit 40 may be a so-called remote controller for operating / stopping the indoor units 2a and 2b, or may check various settings and operation states of the indoor units 2a and 2b and the outdoor unit 1. A remote control device that can be used may be used.

  When the operation of the engine-driven air conditioner 100 is started from the operation unit 40, the operation of the engine 10 is instructed from the control device 30 to generate a driving force, and the compressor 11 is driven by the driving force. For example, in the case of cooling operation, the four-way valve 12 is set in the direction of the broken arrow, and the refrigerant compressed and discharged from the compressor 11 causes the four-way valve 12 to be compressed. Then, the refrigerant flows into the outdoor heat exchanger 13 through heat exchange with the outside air, condenses, is decompressed by the outdoor expansion valve 14, flows through the liquid pipe 3b, is divided, and is divided into the indoor units 2a, 2b. Flows into.

  The refrigerant flowing into the indoor units 2a and 2b flows into the indoor heat exchangers 20a and 20b via the indoor expansion valves 21a and 21b, and evaporates by exchanging heat with the indoor air. The gas flows out to the gas pipe 3a, merges in the gas pipe 3a, flows again into the accumulator 15 via the four-way valve 12 of the outdoor unit 1, and the gas-liquid is separated by the accumulator 15, and the compressor It circulates in the route which flows into No.11.

  In the heating operation, the four-way valve 12 is set in the direction of the solid arrow, and the refrigerant compressed and discharged from the compressor 11 flows through the gas pipe 3a via the four-way valve 12 and is divided. It flows into each indoor unit 2a, 2b, performs heat exchange with indoor air in the respective indoor heat exchangers 20a, 20b, condenses, is decompressed by the indoor expansion valves 21a, 21b, respectively, and flows to the liquid pipe 3b. leak.

  Thereafter, the refrigerant condensed in the indoor heat exchangers 20a and 20b merges in the liquid pipe 3b, returns to the outdoor unit 1, flows into the outdoor heat exchanger 13 via the outdoor expansion valve 14, and this outdoor The heat exchanger 13 evaporates by exchanging heat with the outside air, and flows again into the accumulator 15 via the four-way valve 12. The accumulator 15 separates the gas and liquid and flows into the compressor 11. It will be circulating in.

  In the engine-driven air conditioner 100, for example, an air conditioning load is calculated based on temperature sensors or the like provided in indoor units 2a and 2b (not shown), and operation control of the engine 10 and the compressor 11 is performed. Normal operation means and energy saving operation means for performing air-conditioning operation at a rotation speed at which the operation efficiency of both the engine 10 and the compressor 11 is the best are provided.

  First, the control device 30 will be described. As shown in the block diagram of FIG. 2, various settings of the engine-driven air conditioner 100 and operation instructions to the engine 10 and the compressor 11 are given to the control device 30. A setting unit 31 to perform, a ROM 32 in which a program such as an energy saving operation means of the present invention is stored, a CPU 33 for controlling and calculating the engine-driven air conditioner 100, and the outdoor unit 1 and the indoor units 2a and 2b. A RAM 34 that stores and stores operation data and a transmission / reception unit 35 that communicates with an operation unit 40 described later are stored.

  Further, the RAM 34 also stores the data of the operating efficiency KE of the engine 10 and the data of the operating efficiency KC of the compressor 11 as shown in FIG. 3 used when performing the energy saving operation means of the present invention. Yes. The operating efficiencies KE and KC are data representing whether the operating efficiency of the engine 10 and the compressor 11 with respect to each rotational speed is good or bad as shown in FIG. It should be noted that the data of the operating efficiency KE of the engine 10 and the data of the operating efficiency KC of the compressor 11 are not recorded together with the respective operating efficiencies KE and KC, but are comprehensive based on both operating efficiencies KE and KC. It is good also as what records in RAM34 as the data of the total efficiency KS obtained in this.

  Further, the operation unit 40 will be described. For example, as shown in the front view of FIG. 4, the operation unit 40 includes a display unit 41 that displays the operation state of the engine-driven air conditioner 100 and the engine-driven type. An operation / stop switch 42 for instructing operation / stop of the air conditioner 100, an operation change-over switch 43 for instructing switching of an operation mode such as cooling or heating, and a target indoor temperature (hereinafter referred to as an indoor unit 2a, 2b). A temperature setting switch 44 for setting the temperature), an energy saving switch 45 for instructing the energy saving operation means of the present invention, and the like. Since the energy saving switch 45 is a switch for setting the engine 10 and the compressor 11, it can be provided in the setting unit 31 of the control device 30 described above.

  For example, when the energy saving switch 45 is operated for the first time, an energy saving mark 46 such as an * mark shown in FIG. 4 is lit on the display unit 41 of the operation unit 40, for example. When the driving means is executed and the second operation is performed, the energy saving mark 46 and the like are turned off, and the normal driving means is executed.

  The energy saving operation means of the present invention will be described below.

  Before that, the normal operation means of the engine-driven air conditioner 100 will be described. In this normal operation means, the operation / stop switch 41 and the temperature setting switch 44 of the operation unit 40 are operated and controlled from the operation unit 40. When the operation is instructed to the device 30, for example, based on a temperature difference between an indoor temperature detected by a temperature sensor (not shown) of each indoor unit 2a, 2b and a set temperature instructed by the temperature setting switch 44, or the like. Then, the individual air conditioning loads Ha and Hb of the respective indoor units 2a and 2b are calculated and summed, and the total air conditioning load Hs is calculated. If this total air conditioning load Hs is shown using FIG. 3, it will become as shown in FIG. 5, for example, if the said air conditioning load Hs is a point, the engine 10 and compression so that it may become this a point. The target rotation speed MK1 of the machine 11 is calculated. As a result, the controller 30 instructs the engine 10 and the compressor 11 to operate with the rotational speed MK1 as the target rotational speed, and the air conditioning operation is performed. This operation is performed by the conventional air conditioner. It is not different from the normal driving means used.

  On the other hand, in the present invention, when the energy saving switch 45 of the operation unit 40 is operated for the first time, the data of the operation efficiency KE, KC, or KS of FIG. From point b, the operating efficiency KE, KC of both the engine 10 and the compressor 11 becomes the best, the point a is changed to the point b, and the target of the engine 10 and the compressor 11 is the target. The operation is performed with the rotation speed set as the rotation speed MK2 at the point b. This point b is the rotational efficiency at which the operational efficiency KE of the engine 10 and the operational efficiency KC of the compressor 11 are both the best, or the overall efficiency KS.

  The energy saving operation means will be described with reference to the flowchart shown in FIG. 6. First, it is determined whether or not the engine-driven air conditioner 100 is in operation (step S1). Returning to step S1, the determination of whether or not this operation is in progress is repeated, and if it is in operation, the temperature (not shown) provided in each of the indoor units 2a and 2b shown in FIG. Based on the temperature difference between the indoor temperature detected by the sensor and the set temperature set in the operation unit 40, the air conditioning loads Ha and Hb of the respective indoor units 2a and 2b are calculated and the total air conditioning load Hs. Is determined, and the rotational speed MK1 of the engine 10 and the compressor 11 corresponding to the air conditioning load Hs is determined (step S2).

  Thereafter, an operation of the energy saving switch 45 of the operation unit 40 is performed to determine whether or not execution of the energy saving operation means of the present invention is instructed (step S3), and execution of the energy saving operation means is instructed. For example, it is determined that the engine is the normal operation means, and the target rotational speed MK of the engine 10 and the compressor 11 is determined as the rotational speed MK1 (point a in FIG. 5) obtained from the air conditioning load Hs. (Step S4), the engine 10 and the compressor 11 are operated at the rotational speed MK (that is, the point a), and the operation according to the air conditioning load Hs is performed (step S5).

  On the other hand, if execution of the energy saving operation means is instructed in step S3, the operation efficiency KE, KC of the engine 10 and the compressor 11 shown in FIG. The rotation speed MK2 (point b in FIG. 5) in which both the operating efficiencies KE and KC are the best is obtained from the data, and an instruction is given to set the rotation speed MK as the rotation speed MK2 (step S6). The engine 10 and the compressor 11 are operated at the rotational speed MK (that is, the point b) (step S7).

  As a result, the engine-driven air conditioner 100 can automatically perform the air-conditioning operation at the point b with the best operating efficiency KS, and uses the alternative refrigerant R410a having a high refrigerant capacity per unit volume and low pressure loss. Therefore, it is possible to perform air conditioning operation that promotes energy saving.

  Further, in this energy saving operation means, when the energy saving switch 45 of the operation unit 40 is operated and the execution of the energy saving operation means is instructed as described above, the operation efficiency KE, KC or the overall efficiency KS is the best. Instead of the rotational speed KM2, the rotational speed MK3 that achieves the operating efficiency KE, KC or the overall efficiency KS within the predetermined range with respect to the air conditioning load Hs may be obtained and operated.

  For example, if the predetermined capacity range is 80% to 120% of the air conditioning load Hs, as shown in FIG. 7, the rotational speed MK1 of the engine 10 and the compressor 11 obtained based on the air conditioning load Hs is point a. Even so, when the energy saving switch 45 of the operation unit 40 is operated to instruct the execution of the energy saving operation, the rotation speed MK1 becomes the rotation speed MK3 that becomes 80% of the lowest limit value of the predetermined capacity range. The engine 10 and the compressor 11 may be operated at this rotational speed MK3 (point c).

  The refrigeration capacity Rn1 obtained when operating at the rotational speed MK1 determined based on the air conditioning load Hs is defined as 100%, the total refrigeration capacity Rsum1 obtained from this, and the total fuel consumption consumed for this purpose. Fuel required for obtaining the total refrigeration capacity Rsum2 corresponding to the total refrigeration capacity Rsum1 when the rotation speed MK1 is operated at the rotation speed MK3 of 80% by Fsum1 and the energy saving operation means of the present invention. The consumption amount Fsum2 will be described with reference to the fuel consumption efficiency graph of FIG. 8. When the air conditioning operation is performed at the rotational speed MK1 obtained based on the air conditioning load Hs and the total refrigeration capacity Rsum1 is obtained, the operation is performed. The efficiency decreases to about 1.6 away from the point b where the maximum efficiency is achieved, and the rotational speed MK is higher than the rotational speed MK3. Since in the operation, of course, the fuel consumption rate is high, a 62.5% of fuel consumption Fmax at the maximum rotation of the engine 10. On the other hand, when the energy saving operation means of the present invention is performed, as described above, since the operation is performed at the rotational speed MK3 that is 80% of the rotational speed MK1, the operating efficiency is also set to the maximum efficiency b point. Since it becomes near d point and it improves to about 1.8 and the rotation speed of the engine 10 also falls, the fuel consumption rate at this time falls to 44.4% of the said fuel consumption amount Fmax. For this reason, in order to obtain the total refrigeration capacity Rsum2 corresponding to the total refrigeration capacity Rsum1, the operation time is increased by 25% compared to the case where the operation is performed based on the air conditioning load Hs. The amount Fsum2 can be reduced by 11.1% with respect to the Fsum1.

  Furthermore, even if the obtained refrigeration capacity is reduced by executing this energy saving operation means, as described above, 80% of the air conditioning load Hs requested from the indoor units 2a and 2b and the lower limit value are provided. For this reason, the refrigeration capacity does not decrease more than necessary, and energy-saving operation can be promoted without causing discomfort to the user.

  Moreover, in order to perform the energy saving operation means in which the operation efficiency of both the engine 10 and the compressor 11 is the best, as described above, the data of the operation efficiency KE, the data of the operation efficiency KC, Alternatively, the total efficiency KS data is not recorded in the RAM 34. For example, an arithmetic expression for obtaining the total efficiency KS may be recorded in the ROM 33 or the like and controlled as shown in the flowchart of FIG.

  In this case, first, it is determined whether or not the engine-driven air conditioner 100 is in operation (step S10). If it is not in operation, the process returns to step S10 to determine whether or not this operation is in progress. If the determination whether or not is repeated and the vehicle is in operation, the total air conditioning load Hs is obtained from the air conditioning loads Ha and Hb of the indoor units 2a and 2b shown in FIG. The rotation speed MK1 of the corresponding engine 10 and compressor 11 is obtained (step S11).

  Thereafter, it is determined whether or not the energy saving operation means is being executed (step S12). If execution of the energy saving operation means is not instructed, it is determined that the energy saving operation means is normal operation means, and the engine 10 and the compression An instruction to set the target rotational speed MK of the machine 11 as the rotational speed MK1 obtained from the air conditioning load Hs is performed (step S13), and the engine 10 and the compressor 11 perform the operation at the point a. An operation according to the air conditioning load Hs is performed (step S14).

  On the other hand, if execution of the energy saving operation means is instructed in step S12, the air conditioning load Hs1 that is 80% of the air conditioning load Hs and the air conditioning load Hs2 that is 120% of the previous air conditioning load Hs are the ROM 35. (Step S15), and the engine speeds MKa and MKb of the engine 11 and the compressor 11 corresponding to the calculated air conditioning loads Hs1 and Hs2 are obtained (step S16). Then, it is determined whether or not the rotational speed MKa is larger than the rotational speed MK2 that gives the best overall efficiency KS (step S17). If the rotational speed MK2 is smaller than the rotational speed MKa, the rotational speed MK is set as the rotational speed MKa. (Step S18), the process proceeds to Step S22, and if the rotational speed MK2 is larger than the rotational speed MKa, it is determined whether or not the rotational speed MK2 is larger than the rotational speed MKb (Step S19), and the rotational speed MK2 is the rotational speed. If larger than MKb, the rotational speed MK is set as the rotational speed MKb (step S20), and the process proceeds to step S22. If the rotational speed MK2 is smaller than the rotational speed MKb, the rotational speed MK is set as the rotational speed MK2 (step S21). The engine 10 and the compressor 11 are operated at the rotational speed MK (step S22).

  As a result, the engine-driven air conditioner 100 automatically has the highest operating efficiency KS, can perform air-conditioning operation at point c without causing discomfort to the user, and has a refrigerant capacity per unit volume. Since the alternative refrigerant R410a having a high pressure loss and a low pressure loss is used, it is possible to perform an air conditioning operation that further promotes energy saving.

  In the present embodiment, the engine-driven air conditioner 100 including the compressor 11 that is driven by the driving force of the engine 10 has been described. Even in the electric drive type air conditioner that is provided, the operation efficiency data of the compressor that is variably driven by this electric power is recorded in the RAM 34 and the like, and when the energy saving switch 45 is operated, the electric power It can also be applied as the rotational speed with the highest operating efficiency of a variably driven compressor. Further, the present invention is not limited to the set values and the pipe configurations shown in the above embodiments, and can be appropriately changed without departing from the spirit of the present invention.

  It is suitable for promoting energy-saving operation of a device whose operation efficiency varies depending on the operation state.

It is a block diagram which shows one Embodiment of the engine drive type air conditioning apparatus 100 to which the energy saving operation means of this invention is applied. It is a block diagram which shows the structure of a control apparatus. It is data on the operating efficiency of the engine and the compressor recorded in the RAM in the control device. It is a front view of an operation part. It is the figure which showed the normal driving | operation means and the energy saving operation means of this invention in FIG. It is a flowchart of the energy saving operation means of this invention. FIG. 4 is a diagram showing another embodiment of the energy saving operation means of the present invention in FIG. 3. It is a figure which shows the energy saving property of the energy saving operation means of this invention. It is a flowchart of another Example of the energy saving operation means of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outdoor unit 2a, 2b Indoor unit 3 Inter-unit piping 10 Engine 11 Compressor 12 Four-way valve 13 Outdoor heat exchanger 14 Outdoor expansion valve 15 Accumulator 20a, 20b Indoor heat exchanger 21a, 21b Indoor expansion valve 30 Control apparatus 31 Setting part 32 ROM
33 CPU
34 RAM
35 Transmission / Reception Unit 40 Operation Unit 41 Display Unit 42 Operation / Stop Switch 43 Operation Switching Switch 44 Temperature Setting Switch 45 Energy Saving Switch 100 Engine Driven Air Conditioner

Claims (4)

An indoor unit comprising a compressor driven by the driving force of the engine and an outdoor heat exchanger and one or a plurality of indoor units comprising an indoor heat exchanger are connected by a refrigerant pipe, and the indoor unit In the engine-driven air conditioner that performs the air conditioning operation with variable capacity according to the air conditioning load detected in step 1, the air conditioning load is calculated based on a temperature sensor or the like provided in the indoor unit, and based on the air conditioning load, An engine-driven air conditioner that causes the engine and the compressor to operate at a rotational speed that provides the best operating efficiency and within a predetermined capacity range of the air conditioning load . An indoor unit comprising a compressor driven by the driving force of the engine and an outdoor heat exchanger and one or a plurality of indoor units comprising an indoor heat exchanger are connected by a refrigerant pipe, and the indoor unit In the engine-driven air conditioner that performs the air-conditioning operation with variable capacity according to the air-conditioning load detected in step 1, the air-conditioning load is calculated based on a temperature sensor or the like provided in the indoor unit, and obtained based on the air-conditioning load. Normal operating means for controlling the operation of the engine and the compressor at a determined rotational speed, and the rotational speed at which the operating efficiency of both the engine and the compressor is the best and within the predetermined capacity range of the air conditioning load. An engine-driven air conditioner comprising: an engine and energy-saving operation means for operating the compressor.   3. The engine drive according to claim 2, wherein the normal operation means and the energy saving operation means are operation means selected by operation of an operation unit that instructs operation of the engine-driven air conditioner. Air conditioner. 3. The engine-driven air conditioner according to claim 1, wherein the range of the air conditioning load within the predetermined capacity range is 80% to 120% of the air conditioning load.

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