JP2015098975A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner capable of maintaining comfort without reducing its operating efficiency even when the size of a space to be air-conditioned is changed or an air conditioning load is significantly low.SOLUTION: In this embodiment, a separated type air conditioner 1 whose operation capacity is variable with inverter control includes a pair of indoor unit 1a and outdoor unit 1b. The capacity ratio between the cooling maximum capacity and the cooling minimum capacity thereof during the cooling operation is higher than 20, and the cooling maximum capacity is greater than 8 kW.

Description

  Embodiments described herein relate generally to an air conditioner.

  Conventionally, for example, Patent Document 1 discloses an air conditioner in which the operation capacity can be adjusted by changing the number of cylinders of a compressor, and the outdoor unit is arranged outdoors, and the indoor unit is installed indoors. There is known a separation type air conditioner that is installed on a wall or the like. For example, an air conditioner having a maximum cooling capacity of about 8.1 to 8.2 kW is installed in a relatively large room such as a living room, and can cool a wide space in a short time. For this reason, it has been set so that it can be operated in a relatively high capacity range, and the operation at low capacity has not been considered much. The capacity ratio, which is the ratio between the maximum cooling capacity and the minimum cooling capacity of such a large-capacity air conditioner, is generally about 10 to 15.

Japanese Patent Laid-Open No. 2005-077039

Such a type of air conditioner having a relatively large cooling capacity is selected with an appropriate driving capacity based on the size of a cooling load that can cool a large space to be air-conditioned such as a living room in a short time. For example, when the temperature is not so high depending on the season, or when the space to be air-conditioned is narrowed by partitioning etc., the cooling capacity becomes excessive and the comfort decreases by repeating operation and stop, It was difficult to achieve energy-saving operation with high operating efficiency.
The present embodiment provides an air conditioner that can maintain comfort without reducing operating efficiency even when the size of a space to be air-conditioned changes or when the air-conditioning load is extremely small. This is the issue.

  The air conditioner of the present embodiment is a separation type air conditioner that includes a pair of indoor units and outdoor units and whose operation capability is variable by inverter control, and has a maximum cooling capacity and a minimum cooling capacity during cooling operation. The capacity ratio is greater than 20, and the maximum cooling capacity is greater than 8 kW.

The figure which shows typically the aspect when driving the compressor of the air conditioner of 1st Embodiment by 1 cylinder. The figure which shows typically the aspect when operating the compressor of the air conditioner of 1st Embodiment by 2 cylinders. The figure which shows an example of the driving capability of the air conditioner of 1st Embodiment. The figure which shows an example of the operating frequency of the air conditioner of 1st Embodiment. The figure which shows typically the flow of the air-conditioning control of the air conditioner of 1st Embodiment. The figure which shows an example of the operating frequency of the air conditioner of 2nd Embodiment.

Hereinafter, a plurality of embodiments will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the site | part substantially common in each embodiment, and the detailed description is abbreviate | omitted.
(First embodiment)
Hereinafter, the first embodiment will be described with reference to FIGS. 1 to 5.
As shown in FIG. 1, the air conditioner 1 constitutes a known refrigeration cycle including an indoor unit 1a and an outdoor unit 1b. The indoor unit 1a is formed in a substantially horizontally long rectangular parallelepiped shape that is used in general homes and the like, and its horizontal width in an installed state is designed to be 800 mm or less and its height is 295 mm or less. That is, the indoor unit 1a has a width of approximately one tatami or less. The indoor unit 1a is connected to the outdoor unit 1b by piping, a power line, a signal line, and the like.

  The outdoor unit 1b includes a control unit 2, an inverter circuit 2a, a compressor 3, a piping member 4, a four-way switching valve 5, and the like. The control part 2 is comprised by the microcomputer which has CPU, ROM, RAM, etc. which are not shown in figure, for example, controls the outdoor unit 1b by running the computer program memorize | stored in ROM etc. In addition, although the control performed by the control part 2 is various, here, control of the compressor 3 is demonstrated in relation to embodiment.

  The controller 2 controls the operating frequency of the compressor 3 by driving the inverter circuit 2a. Since the inverter circuit 2a itself can adopt a known configuration, description thereof is omitted. This compressor 3 is a two-cylinder rotary type, and a compression mechanism section 6 is provided on the lower side in the main body, and an electric motor section constituted by a motor or the like (not shown) is provided on the upper part. The electric motor unit and the compression mechanism unit 6 are connected via a rotating shaft of a motor. The inverter circuit 2a controls the operating frequency of the compressor 3 by controlling the motor of the electric motor unit.

  The compression mechanism section 6 includes an upper cylinder 7 and a lower cylinder 8 that are disposed up and down via an intermediate partition plate (not shown). The upper cylinder 7 and the lower cylinder 8 are designed such that the outer shape dimensions are different from each other and the inner diameter dimensions are the same. Specifically, the upper cylinder 7 is formed with an outer diameter dimension slightly larger than an inner diameter dimension of the main body case at the time of manufacture, and after being press-fitted into the inner peripheral surface of the main body case, the upper cylinder 7 is positioned and fixed by welding. .

  A main bearing (not shown) is fixed to the upper surface of the upper cylinder 7. A sub bearing (not shown) is fixed to the lower surface of the lower cylinder 8. The outer diameter of the intermediate partition plate and the auxiliary bearing is designed to be somewhat larger than the inner diameter of the lower cylinder 8. The inner diameter position of the lower cylinder 8 is set at a position eccentric from the center of the cylinder. Therefore, a part of the outer periphery of the lower cylinder 8 projects outward in the radial direction from the outer diameters of the intermediate partition plate and the auxiliary bearing.

  The rotating shaft of the motor has a midway portion and a lower end portion rotatably supported by the main bearing and the sub bearing. The rotating shaft passes through the upper cylinder 7 and the lower cylinder 8 and is attached with two eccentric portions provided with a phase difference of about 180 °. Each eccentric part has the same diameter, and is located in the inner diameter part of the upper cylinder 7 and the lower cylinder 8, respectively. A rolling piston having the same diameter is attached to each eccentric part. The rolling piston is housed in each cylinder chamber of the upper cylinder 7 and the lower cylinder 8 so as to be eccentrically rotatable. FIG. 1B shows a rolling piston 8a housed in the lower cylinder 8.

  Each rolling piston is set so as to have the same excluded volume in each cylinder by rotating eccentrically in the upper cylinder 7 and the lower cylinder 8 with a phase difference of 180 ° from each other. The upper cylinder 7 and the lower cylinder 8 are provided with vanes 9 and 11, respectively. As shown in FIG. 2A, the vanes 9 and 10 are urged toward the cylinders by elastic members 10a and 10b such as springs, respectively, and as shown by arrows Y1 and Y2, the rolling pistons It is provided so as to be able to project and retract in the cylinder according to the rotation of the cylinder.

  Among these, the vane 11 corresponding to the lower cylinder 8 is controlled by the electromagnet 12 in the protruding and retracting manner. Specifically, the vane 11 is attracted to the electromagnet 12 as shown in FIG. 1 (A) and cannot enter the cylinder, and detached from the electromagnet 12 as shown in FIG. 2 (A). The state is controlled so as to be freely retractable into the cylinder. The state shown in FIG. 1A corresponds to a state in which the lower cylinder 8 is idling without being compressed, that is, a one-cylinder operation state. Further, the state shown in FIG. 2A corresponds to a state in which the compression operation is performed in the lower cylinder 8, that is, a state of 2-cylinder operation. The control of the operation state is performed by the control unit 2.

  In the one-cylinder operation and the two-cylinder operation, the four-way switching valve 5 provided in the piping member 4 is switched. Specifically, in the one-cylinder operation, as shown in FIG. 1 (A), the path connected to the lower cylinder 8 is switched to the discharge side (high pressure side) of the compressor 3 by the four-way switching valve 5, and FIG. ), The lower cylinder 8 is always in a high-pressure state throughout the entire area. On the other hand, in the two-cylinder operation, as shown in FIG. 2 (A), the path leading to the lower cylinder 8 is switched to the accumulator side, that is, the suction side (low pressure side) by the four-way switching valve 5, as shown in FIG. 2 (B). As described above, the lower cylinder 8 has a high pressure region and a low pressure region formed before and after the vane 11 in the rotational direction.

  By switching between the one-cylinder operation and the two-cylinder operation in this manner, the adjustment range of the driving ability can be made variable as in a first range and a second range described later. In this case, when the maximum cooling capacity is required, a two-cylinder operation is performed in which the maximum number of cylinders to be used (two in this embodiment) is performed, and when the minimum cooling capacity is required, it is used. One-cylinder operation is performed to minimize the number of cylinders (one in this embodiment). In each adjustment range, the driving ability can be adjusted by changing the driving frequency as described later.

  In the case of the air conditioner of the present embodiment, the cooling rated capacity is 8.0 kW, the minimum cooling capacity is 0.2 kW, and the maximum cooling capacity is 8.2 kW as shown in FIG. 3 as “the air conditioner of the embodiment”. Is set. The capacity ratio is the maximum cooling capacity / minimum cooling capacity = 8.2 / 0.2 = 41.0. Thus, if the maximum cooling capacity is about 8.2 kW, the cooling capacity will not be insufficient even if the space to be cooled is a large space, for example, about 20 tatami mats, and the minimum cooling capacity is 0. If it is about 2 kW, even if the space to be air-cooled is partitioned and becomes, for example, about 4 tatami halves as described later, there is little possibility that the air-conditioning capacity will be excessive and it will be too cool. Can be suppressed.

  On the other hand, as shown in FIG. 3 as “conventional air conditioner 1” and “conventional air conditioner 2”, the conventional air conditioner has the same cooling rated capacity of 8 as the air conditioner of the present embodiment. Even if it is 0.0 kW, for example, the cooling capacity is 0.8 kW, the cooling capacity is 8.1 kW, the capacity ratio is 10.1, the cooling capacity is 0.5 kW, and the cooling capacity is 8.2 kW. As the capacity ratio is 16.4, the capacity ratio is low, in other words, the adjustment range of the cooling capacity is narrow.

  In this case, for example, when air-conditioning a 20 tatami living room or the like as it is, it is assumed that any air conditioner can perform the same air conditioning. However, for example, when a corner where the indoor unit 1a is installed is divided into a small space or the indoor temperature is low, the conventional air conditioner has excessive cooling capacity even if it is operated with the minimum cooling capacity. It is assumed that As a result, the partitioned space is too cold, the operation is stopped and the operation is stopped to maintain the set temperature, the comfort is lowered, and it is difficult to achieve an energy-saving cooling operation with high operation efficiency.

  In contrast, in the case of the air conditioner 1 of the present embodiment, the air conditioning adjustment range is set such that the capacity ratio between the maximum cooling capacity and the minimum cooling capacity during the cooling operation is greater than 20, and the minimum cooling capacity side is set lower. Therefore, even when partitioning or when the temperature is low, it is possible to continuously operate in a cooling capacity range smaller than before. This makes it possible to achieve energy-saving operation with high operation efficiency even in a small cooling capacity region without being too cold from the set temperature or reducing comfort by repeating operation and stop to maintain the set temperature. In this case, in the air conditioner 1 of the embodiment, since the maximum cooling capacity is 8.2 kW, in order to ensure a capacity ratio of 20 or more, the minimum cooling capacity may be 0.41 kW or less. Further, when the maximum cooling capacity is 8.0 kW or more, the minimum cooling capacity may be 0.4 kW or less.

  Further, in the case of the air conditioner 1 of the present embodiment, as shown in FIG. 4, the adjustment interval (corresponding to the first range) of the operation frequency of the compressor 3 during the one-cylinder operation is greater during the two-cylinder operation. The operating frequency of the compressor 3 is set narrower than the adjustment interval (corresponding to the second range). Specifically, in this embodiment, the operation frequency adjustment interval in the case of 1-cylinder operation is set in units of 0.3 Hz, while the operation frequency adjustment interval in the case of 2-cylinder operation is in units of 0.4 Hz. Is set. Among these, the operation in the state where the operation frequency is minimum in the first range corresponds to the operation in the minimum cooling capacity where the cooling capacity is minimum, and the operation in the state where the operation frequency is maximum in the second range. This corresponds to the operation at the maximum cooling capacity that maximizes the cooling capacity.

  For this reason, when the one-cylinder operation in which the difference between the set temperature and the room temperature is small and the air conditioning load is small and the cooling capacity is relatively low is selected, the adjustment interval is narrow. The frequency can be finely controlled. That is, it is easy to perform control to bring the room temperature closer to the set temperature. On the other hand, when the two-cylinder operation is selected in which the difference between the set temperature and the room temperature is large and the air conditioning load is large and the cooling capacity is relatively high, the adjustment interval is relatively wide. While ensuring the air conditioning capability, it is possible to approach the set temperature sooner.

Next, the operation of the air conditioner 1 described above will be described. In addition, although the following control is mainly performed by the above-mentioned control part 2, it demonstrates focusing on the air conditioner 1 here.
The air conditioner 1 performs the air-conditioning control shown in FIG. 5. When the power is turned on, the air conditioner 1 reads the settings such as the cooling operation or the set temperature (S1), and sets the room temperature. Obtain (S2). Then, assuming an air conditioning load from the room temperature, the set temperature, etc., the air conditioning load is larger than a reference value (corresponding to a selection reference value) that is a criterion for determining whether to select 1-cylinder operation or 2-cylinder operation. Is determined (S3).

  And if the air conditioner 1 determines that the air conditioning load is smaller than the reference value (S3: NO), one cylinder operation is set (S4), and the adjustment range of the operating frequency of the compressor 3 is the first range described above. (S5) and air conditioning control is performed (S6). In step S6, well-known air conditioning control is performed. On the other hand, when the air conditioner 1 determines that the air conditioning load is larger than the reference value (S3: YES), the two-cylinder operation is set (S7), and the adjustment range of the operation frequency of the compressor 3 is the second range described above. (S8) and air conditioning control is performed (S6).

Thus, the air conditioner 1 selects the 1-cylinder operation and the 2-cylinder operation according to the assumed load. Thereby, it can drive | operate by optimal cooling capacity, suppressing power consumption. That is, the air conditioner 1 has high energy saving performance.
At this time, since the capacity ratio between the maximum cooling capacity and the minimum cooling capacity during the cooling operation is larger than 20 and the maximum cooling capacity is larger than 8 kW, the air conditioning capacity can be improved even in a large room such as 20 tatami mats. It can be ensured, and comfort can be maintained while suppressing unnecessary energy consumption even when the partitioned small space is cooled or when the temperature is low depending on the season.

In addition, since the air conditioner 1 has a cooling minimum capacity of 0.41 kW or less (in the embodiment, 0.2 kW), the air conditioner 1 is not excessively cooled even in a partitioned small space, so that comfort is improved. Can keep.
In addition, the air conditioner 1 has a compressor 3 that can change the number of cylinders used during operation. When the air conditioner 1 is operated at the maximum cooling capacity, the air conditioner 1 is operated with the maximum number of cylinders and is operated at the minimum cooling capacity. Sometimes it operates with the number of cylinders minimized. As a result, energy consumption can be further suppressed during operation at the minimum cooling capacity.

  In addition, the air conditioner 1 varies the operation frequency adjustment interval between the one-cylinder operation and the two-cylinder operation. Specifically, the one-cylinder operation can be adjusted more finely. Thereby, at the time of 1-cylinder operation | movement, the followability with respect to setting temperature becomes high, and comfort can be improved more. On the other hand, at the time of 2-cylinder operation, it is possible to approach the set temperature sooner while ensuring air conditioning capability. In addition, when the air conditioning load is large, the control interval is widened, so the amount of control data required is relatively small, reducing the processing load during operation, and further reducing the verification tests during development and manufacturing. Reliability and productivity can be improved.

  Also, comfort can be improved by performing fine control during 1-cylinder operation, while in 2-cylinder operation, the rolling pistons move in opposite directions with a phase difference of approximately 180 ° as described above. Since it operates, vibration and the like are suppressed, and silence is increased. For this reason, when air conditioning is possible in both the first range and the second range, it is important to make fine adjustments by operating near the upper limit of the adjustment range of the one-cylinder operation. It is also possible to increase the degree of freedom in selecting whether to operate with a low operating frequency on the lower limit side of the adjustment range of cylinder operation and to place importance on quietness.

(Second Embodiment)
Hereinafter, the second embodiment will be described with reference to FIG. In addition, since the structure of the air conditioner 1 is common in 1st Embodiment, it demonstrates with the same code | symbol.
In the air conditioner 1 of the second embodiment, as shown in FIG. 6, the minimum value of the operation frequency in the operation state where the number of cylinders to be used is the minimum (1 cylinder operation in the present embodiment), that is, the compressor 3 is operated. The minimum value of the operating frequency in the operating state (two-cylinder operation in the present embodiment) in which the number of cylinders to be used is larger than the minimum value of the operating frequency in the state (4.8 Hz in the first range of FIG. 6), That is, the minimum value of the operating frequency when the compressor 3 is in the operating state (9.6 Hz in the second range in FIG. 6) is set to be large.

In addition, the air conditioner 1 has a maximum value of the operation frequency in the two-cylinder operation (130 in the second range of FIG. 6) rather than the maximum value of the operation frequency in the one-cylinder operation (25.1 Hz in the first range of FIG. 6). .4 Hz) is set to be large.
Thereby, the air conditioner 1 of the present embodiment can be operated with lower capacity as the number of cylinders is smaller. On the other hand, as the number of cylinders increases, the operation with higher capacity becomes possible. Therefore, in a small space partitioned as described above, comfort can be maintained without causing excessive cooling, and unnecessary ghee consumption can be suppressed.

Further, in the air conditioner 1, a value obtained by multiplying the maximum value of the operating frequency in the one-cylinder operation (25.1 Hz in the first range in FIG. 6) by the number of cylinders is the minimum value of the operating frequency in the two-cylinder operation (FIG. 6). In the second range of 9.6 Hz). In other words, the minimum value of the operation frequency in the 2-cylinder operation (9.6 Hz in the second range in FIG. 6) is smaller than the maximum value of the operation frequency in the 1-cylinder operation (25.1 Hz in the first range in FIG. 6). It is set to become.
Thereby, a more efficient driving | operation can be performed in a wider area | region and the performance improvement of the air conditioner 1 can be aimed at. In addition, as in the first embodiment, it is possible to increase the degree of freedom whether priority is given to fine adjustment or quietness.

(Other embodiments)
The air conditioner 1 is not limited to the configuration exemplified in the above-described embodiment, and can be modified or expanded as follows. In addition, the configurations exemplified in the above-described embodiment and the configurations exemplified in the following modified examples and extended examples can be partly or entirely combined.

  The upper and lower limits of the adjustment range exemplified in each embodiment, or the number of adjustable operating frequencies (hereinafter referred to as the number of steps for convenience) is an example, and is not limited to this. For example, in each embodiment, the number of steps that can be adjusted is the same between the first range and the second range, but the number of steps may be different between the first range and the second range. For example, in the first range where the air conditioning load is small, the number of switching steps is increased at narrower intervals such as 0.1 Hz and 0.2 Hz, and finer adjustment is possible, and in the second range where the air conditioning load is large, 0.5 Hz and so on. It is also possible to adjust the room temperature to near the set temperature more quickly by reducing the number of switching steps from the first range at the above wide intervals.

  In each embodiment, the compressor 3 having a two-cylinder configuration is illustrated, but a configuration including a plurality of n cylinders such as three or four cylinders may be used. In that case, the adjustment range of the operating frequency is set as the first to nth ranges according to the number of cylinders as in the embodiment, and the adjustment interval of the first range is smaller than the adjustment interval of the nth range. The maximum value of the first range is larger than the minimum value of the n-th range, and the maximum value of the n-th range is larger than the maximum value of the first range. By making the value obtained by multiplying the number of cylinders used in the adjustment range larger than the minimum value in the nth range, the same effect as in each embodiment can be obtained.

  For example, when the first to third ranges are set, the adjustment interval of the first range is made smaller than the adjustment interval of the second range, and the adjustment interval of the second range is made smaller than the adjustment interval of the third range. Alternatively, a value obtained by multiplying the maximum value of the first range by the number of cylinders (one) used in the adjustment range is set to be larger than the minimum value of the second range, and the maximum value of the second range is A value obtained by multiplying the number of cylinders (2) used in the adjustment range may be larger than the minimum value in the third range. The same applies to other settings.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  In the drawings, 1 is an air conditioner, 1a is an indoor unit, 1b is an outdoor unit, 2 is a control unit, 2a is an inverter circuit, 3 is a compressor, 6 is a compression mechanism, 7 is an upper cylinder (cylinder), 8 is The lower cylinder is shown.

Claims (4)

A separate type air conditioner that is composed of a pair of indoor units and outdoor units and has variable operation capacity by inverter control,
An air conditioner characterized in that the capacity ratio between the maximum cooling capacity and the minimum cooling capacity during cooling operation is greater than 20, and the maximum cooling capacity is greater than 8 kW.   The air conditioner according to claim 1, wherein the minimum cooling capacity is 0.4 kW or less.   The outdoor unit has a compressor that can change the number of cylinders used during operation, operates with the maximum number of cylinders when operating with the maximum cooling capacity, and operates with the minimum cooling capacity. The air conditioner according to claim 1 or 2, wherein the air conditioner is operated with the number of cylinders being minimized.   The air conditioner according to any one of claims 1 to 3, wherein the indoor unit has a lateral width in an installed state of 800 mm or less and a height of 295 mm or less.

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