JP4842014B2 - Air conditioner - Google Patents

Description

  The present invention relates to an air conditioner, and more particularly to an air conditioner in which a plurality of indoor units connected to one outdoor unit perform simultaneous cooling and heating operations.

  A multi-type cooling / heating simultaneous operation air conditioner that simultaneously performs cooling operation and heating operation with multiple indoor units connected to one outdoor unit is a high-pressure gas refrigerant pipe, low-pressure gas refrigerant pipe, liquid refrigerant pipe from the outdoor unit side These three connection pipes are drawn out. On the other hand, there are two connection pipes, a gas refrigerant pipe and a liquid refrigerant pipe, on the side of the plurality of indoor units, and the liquid refrigerant pipe on each indoor unit side is connected to the liquid refrigerant pipe on the outdoor unit side. In addition, a cooling / heating switching unit is provided for each indoor unit, and the cooling / heating switching unit is controlled so that the gas refrigerant pipe on each indoor unit side, the high-pressure gas refrigerant pipe and the low-pressure gas refrigerant pipe on the outdoor unit side, Is switched to switch between cooling operation and heating operation of each indoor unit.

  In Patent Document 1, switching of connection between the high-pressure gas refrigerant pipe on the outdoor unit side and the gas refrigerant pipe on the indoor unit side is controlled by a first on-off valve, and the low-pressure gas refrigerant pipe on the outdoor unit side and the gas on the indoor unit side are controlled. It is described that the switching of the connection with the refrigerant pipe is controlled by a second on-off valve. According to this, by controlling the opening and closing of each on-off valve, it is said that all the indoor units can be in a heating operation, all in a cooling operation, or a cooling operation and a heating operation can be performed simultaneously. ing.

Japanese Patent Laid-Open No. 02-093263

  However, Patent Document 1 does not describe the configuration of the on-off valve in detail. As such an on-off valve, for example, it is conceivable to use an electromagnetic valve that opens and closes by moving the piston up and down.However, since the piston diameter of the electromagnetic valve is generally small, the flow path of the refrigerant is restricted and the pressure loss is reduced. Increase. In order to reduce such pressure loss, it is necessary to increase the piston diameter, and there is a problem that the size of the solenoid valve itself is increased.

  In addition, the solenoid valve is problematic because it can only select either the open or closed refrigerant flow path. That is, for example, when a plurality of indoor units are performing simultaneous cooling and heating, if the connection between the gas refrigerant pipe on the indoor unit side performing the cooling operation and the high-pressure gas refrigerant pipe on the outdoor unit side is completely closed The high-pressure gas refrigerant that can no longer circulate in the refrigeration cycle circuit is cooled and condensed, and may become liquid refrigerant and accumulate in the piping. In order to avoid this, a bypass pipe for bypassing the closed solenoid valve and allowing the refrigerant to flow slightly is required.

  This invention makes it a subject to implement | achieve the cooling / heating switching unit which can reduce the pressure loss of a refrigerant | coolant and can adjust the flow volume of a refrigerant | coolant.

To solve the above problems, an air conditioner of the present invention, the pipe for circulating the refrigerant, the compressor and an outdoor unit having an outdoor heat exchanger, a plurality of indoor units having an indoor heat exchanger and an indoor expansion valve by plugging it to form a refrigeration cycle, a plurality of the respective gas refrigerant pipe of the indoor unit side, at least one of a the connection to the indoor low-pressure gas refrigerant pipe and the high pressure gas refrigerant pipe of the outdoor unit side A cylindrical cylinder having a cooling / heating switching unit for switching the cooling / heating operation of the machine, wherein each cooling / heating switching unit is connected to a gas refrigerant pipe, a low-pressure gas refrigerant pipe and a high-pressure gas refrigerant pipe. When this cylindrical cylinder gas refrigerant pipe is fitted into a cylindrical refrigerant flow path is formed to communicate with each other a low-pressure gas refrigerant pipe and the high pressure gas refrigerant pipe rotor, the rotation of the cylindrical rotor By controlling the phase, characterized in that configured in the switching control means switching the cooling and heating operations.

That is, the cylindrical rotor is formed with a refrigerant flow path that connects the gas refrigerant pipe on the indoor unit side and the gas refrigerant pipe on the outdoor unit side (hereinafter referred to as each refrigerant pipe). The channel area can be equal to or greater than that of each refrigerant pipe. Then, by controlling the rotational phase of the rotor to a position where each refrigerant pipe communicates with the switching control means, it is possible to reduce the pressure loss of the refrigerant and distribute the refrigerant. As a result, it is possible to reduce the pressure loss of the refrigerant when the refrigerant is circulated while suppressing the size of the cooling / heating switching unit. Here, the cooling / heating switching unit is composed of a single switching unit to which three pipes of a gas refrigerant pipe on the indoor side, a high-pressure gas refrigerant pipe on the outdoor side, and a low-pressure gas refrigerant pipe on the outdoor side are connected. By controlling the rotational phase, the three pipes or the indoor gas refrigerant pipe and any one of the gas refrigerant pipes can be communicated with each other through a refrigerant flow path with little pressure loss.

  In addition, by controlling the rotation phase of the rotor with the switching control means and adjusting the area of the overlapping portion between the refrigerant flow path formed in the rotor and each refrigerant pipe, the refrigerant flow path is selected to be either open or closed In addition, the flow rate of the refrigerant can be arbitrarily adjusted. According to this, for example, when a plurality of indoor units are performing simultaneous cooling and heating operations, the connection between the gas refrigerant pipe on the indoor unit side that is performing the cooling operation and the high-pressure gas refrigerant pipe on the outdoor unit side is completely established. Since it is possible to form a refrigerant flow path through which the refrigerant is circulated minutely without being closed, it is possible to omit a conventionally used bypass pipe.

Thus, according to the air conditioner of the present invention, it is possible to realize an air conditioning switching unit that can reduce the pressure loss of the refrigerant and adjust the flow rate of the refrigerant.

  ADVANTAGE OF THE INVENTION According to this invention, the cooling / heating switching unit which can reduce the pressure loss of a refrigerant | coolant and can adjust the flow volume of a refrigerant | coolant is realizable.

  Hereinafter, an embodiment of an air conditioner to which the present invention is applied will be described with reference to FIGS. In the following description, the same functional parts are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic diagram showing the overall configuration of the air conditioner of the present embodiment. As shown in FIG. 1, the air conditioner 1 of the present embodiment is configured by connecting three indoor units 3 a to 3 c in parallel to one outdoor unit 2. The number of indoor units 3 is not limited to this and can be increased or decreased. The outdoor unit 2 includes compressors 5a to 5c, four-way valves 6a and 6b, outdoor heat exchangers 7a and 7b, outdoor expansion valves 8a and 8b, a receiver 9, a supercooling heat exchanger 10, a supercooling bypass expansion valve 11, and an accumulator. 12 and the like, and each indoor unit 3 includes indoor heat exchangers 14a to 14c, indoor expansion valves 15a to 15c, and the like. An electromagnetic valve or the like may be used in place of the four-way valves 6a and 6b.

  Further, for each indoor unit 3, the indoor unit-side gas refrigerant pipes 17 a to 17 c drawn from the indoor heat exchangers 14 a to 14 c and the outdoor led out from the outdoor unit 2 and branched to each indoor unit 3. Cooling / heating switching units 20a to 20c for switching the cooling / heating operation by connecting at least one of the high-pressure gas refrigerant pipings 18a to 18c and the low-pressure gas refrigerant pipings 19a to 19c on the machine side are provided.

  Next, the flow of the refrigerant in the refrigeration cycle formed by such an air conditioner 1 will be described. In the present embodiment, an example will be described in which the indoor unit 3a is in a heating operation and the indoor units 3b and 3c are in a cooling operation. A part of the high-pressure gas refrigerant compressed by the compressors 5a to 5c is sent to the outdoor heat exchanger 7a through the four-way valve 6a, and the rest is supplied to the high-pressure gas refrigerant through the four-way valve 6b and the high-pressure gas refrigerant blocking valve 22. It is sent to the pipe 18.

  Here, the first switching valve 24a of the cooling / heating switching unit 20a is opened, the second switching valve 25a is closed, and the first switching valves 24b, c of the cooling / heating switching unit 20b, c are closed. Therefore, the high-pressure gas refrigerant sent to the high-pressure gas refrigerant pipe 18 is sent to the indoor unit 3a that performs the heating operation. The high-pressure gas refrigerant that has passed through the cooling / heating switching unit 20a through the first switching valve 24a is sent to the indoor unit 3a through the indoor-side gas refrigerant pipe 17a, and exchanges heat with indoor air in the indoor heat exchanger 14a. The liquid refrigerant is condensed and then sent to the liquid refrigerant pipe 27 via the indoor expansion valve 15a.

  On the other hand, the high-pressure gas refrigerant sent to the outdoor heat exchanger 7a is condensed by exchanging heat with the outdoor air to become liquid refrigerant, and the outdoor expansion valve 8a, the receiver 9, the supercooling heat exchanger 10, and the liquid refrigerant blocking valve 29. To the liquid refrigerant pipe 27. Here, the outdoor expansion valve 8b is closed, and the refrigerant does not flow into the outdoor heat exchanger 7b.

  The liquid refrigerant sent from the indoor unit 3a and the outdoor unit 2 performing the heating operation to the liquid refrigerant pipe 27 is sent to the indoor units 3b and 3c performing the cooling operation, and is expanded by the indoor expansion valves 15b and 15c. The heat exchangers 14b and 14c exchange heat with room air to form a low-pressure gas refrigerant, which is sent to the cooling / heating switching units 20b and 20c via the gas connection pipes 17b and 17c on the indoor unit side. Here, since the first switching valves 24b and 24c of the cooling / heating switching units 20b and 20c are closed and the second switching valves 25b and 25c are opened, the low-pressure gas that has passed through the second switching valves 25b and 25c. The refrigerant returns to the compressors 5a to 5c through the low-pressure gas refrigerant pipe 19, the low-pressure gas refrigerant blocking valve 30, and the accumulator 12, and is recirculated.

  As described above, in the cooling / heating switching units 20a to 20c, the first switching valves 24a to 24c and the second switching valves 25a to 25c are switched and controlled, so that the cooling operation and the heating operation of each indoor unit 3 are independently controlled. It becomes possible to do.

  Next, the details of the cooling / heating switching units 20a to 20c, which are features of the present invention, will be described. Since the first switching valves 24a to 24c and the second switching valves 25a to 25c in the cooling / heating switching units 20a to 20c have the same configuration, the first switching valve 24a will be representatively described.

  Fig.2 (a) is a figure which shows the longitudinal cross-section of the 1st switching valve 24a, FIG.2 (b) is a figure which shows the cross section of the bb line in Fig.2 (a). As shown in FIG. 2, the first switching valve 24 a includes a cylindrical cylinder 32 in which connection ports 31 to which the gas refrigerant pipe 17 on the indoor unit side and the high-pressure gas refrigerant pipe 18 on the outdoor unit side are respectively connected are formed. And a cylindrical rotor 34 that is fitted inside a cylindrical cylinder 32 and has a refrigerant flow path 33 that communicates the gas refrigerant pipe 17 on the indoor unit side and the high-pressure gas refrigerant pipe 18 on the outdoor unit side, The switching control means 35 controls the rotation phase of the cylindrical rotor 34 to switch the cooling / heating operation.

  Next, the switching control means 35 for controlling the rotation phase of the rotor 34 will be described with reference to FIG. 3A is a diagram showing a longitudinal section of the switching control means 35, and FIGS. 3B and 3C are sectional views taken along lines bb and cc in FIG. 3A. . In this embodiment, a step motor is used for the rotation mechanism of the rotor 34. As shown in FIG. 3, the step motor includes a stator 38 having a coil wound around an iron core and a rotor 39 formed of a magnetic material. Although the stator 38 is divided into six in FIG. 3, the number may be more or less.

  Assuming that a current is passed through the stators 38a and 38b, the rotor 39 stops at the position shown in FIG. In this state, when the current of the stators 38a and 38b is turned off and the current is passed through the stators 38c and 38d, the rotor 39 rotates 30 ° clockwise. When the current of the stators 38c and d is cut off and the current is passed through the stators 38e and 38f, the rotor 39 further rotates 30 ° clockwise. Here, the rotational phase of the rotor 34 can be controlled by controlling the number of times the current is turned on and off, and reverse rotation is also possible by reversing the order in which the current flows. Further, by increasing the number of stators 39, finer phase adjustment is possible. In this embodiment, the rotational phase is finely adjusted by the gear mechanism described below.

  As shown in FIG. 3A, the rotor 39 and the gear 40 are fixed via a power transmission mechanism 41. When the rotor 39 is rotated by the step motor, the gear 40 is rotated in the same phase as the rotation. . Since the gear 42 that meshes with the gear 40 is fixed to the rotor 34 via the power transmission mechanism 43, when the gear 42 rotates as the gear 40 rotates, the rotor 34 rotates in the same phase as the gear 42. Here, when the rotation of the gear 40 is transmitted to the gear 42, for example, if the number of teeth of the gear 40 is N1 and the number of teeth N2 of the gear 42, the gear 42 rotates N1 / N2 with respect to one rotation of the gear 40. By making the number of teeth of the gear 40 smaller than that of the gear 42, a finer rotation phase adjustment can be performed. In this embodiment, the rotational phase of the rotor 34 is finely adjusted with two gears. However, the phase may be finely adjusted by increasing the number of gears. Alternatively, the power transmission mechanism 41 may be directly fixed to the rotor 34 without the gear mechanism, and the rotation phase of the rotor 34 may be controlled only by the rotation control of the step motor.

  Next, the rotation phase control of the rotor 34 with respect to the operating condition of the air conditioning of the indoor unit 3 will be described. As shown to Fig.4 (a), when the indoor unit 3 is performing heating operation, what is necessary is just to open the 1st switching valve 24 and close the 2nd switching valve 25 fundamentally. In order to open the first switching valve 24, the rotational phase of the rotor 34 may be controlled so that the high-pressure gas refrigerant pipe 18 on the outdoor unit side and the gas refrigerant pipe 17 on the indoor side communicate with each other. In order to close the second switching valve 25, the rotor 34 may be rotated to a position where the refrigerant passage 33 is not in contact with the high-pressure gas refrigerant pipe 19 on the outdoor unit side or the gas refrigerant pipe 17 on the indoor side.

  As shown in FIG. 4B, during the cooling operation, the rotor 34 is rotated so that the first switching valve 24 is closed and the second switching valve 25 is opened. As shown in FIG. 4C, when the low-pressure gas refrigerant is caused to flow through the high-pressure gas refrigerant pipe 18 on the outdoor unit side during the all-room cooling operation, the first switching valve 24 and the second switching valve 25 are used. The rotor 34 may be rotated so that both are open.

  As described above, in the first and second switching valves of the present embodiment, the refrigerant flow path 33 is formed in the rotor 34, so that there is no restriction such as the piston diameter of a conventionally used electromagnetic valve, The refrigerant flow path 33 can be formed with the same size as the pipe for circulating the refrigerant. Therefore, it is possible to reduce the pressure loss of the refrigerant when the refrigerant is circulated while suppressing the size of the cooling / heating switching unit 20.

  By the way, when a plurality of indoor units 3 are connected to one outdoor unit 2 as in this embodiment, and each of the indoor units 3 performs a cooling operation and a heating operation at the same time, the first and second switching valves are set. Problems may arise if only opening or closing is selected. That is, for example, when the outdoor unit 2 is in the simultaneous cooling and heating operation and the high pressure gas refrigerant is present in the high pressure gas refrigerant pipe 18 on the outdoor unit side, if the first switching valve 24 is completely closed, the high pressure gas on the outdoor unit side is closed. In some cases, the high-pressure gas refrigerant is gradually condensed by the heat radiation of the refrigerant pipe 18 and accumulates as a liquid refrigerant in the closed branch pipe portion of the high-pressure gas refrigerant pipe 18 on the outdoor unit side, and the entire refrigeration cycle may be insufficient. In order to solve such a problem, in the air conditioner of the present embodiment, the refrigerant flow rate is adjusted as follows.

  Fig.5 (a) is a figure which shows the cooling / heating switching unit 20 with respect to the indoor unit which performs air_conditionaing | cooling operation in the state in which the outdoor unit 2 is performing simultaneous cooling / heating operation. In this way, the first switching valve 24 is not completely closed, but the rotational phase of the rotor 34 is controlled, whereby the refrigerant flow path 33, the gas refrigerant pipe 17 on the indoor unit side, and the outdoor unit side are controlled. The area of the overlapping part with the high-pressure gas refrigerant pipe 18 is formed slightly.

  Thus, by controlling the rotation phase of the rotor 34 by the switching control means 35, the refrigerant continues to flow slightly through the first switching valve 24, so that the problem of liquid refrigerant accumulation can be solved. . As a result, the bypass pipe for passing the refrigerant by bypassing the first switching valve 24 has been conventionally provided. However, according to the present embodiment, the refrigerant can be circulated minutely without providing the bypass pipe. Can do.

  Further, during the normal cooling operation, the rotational phase of the rotor 34 is controlled so that the second switching valve 25 is opened. However, when the outside air is cooled at a low temperature, the indoor pressure is reduced to the suction pressure and the cooling capacity is increased. In some cases, the liquid may be excessively discharged, or the evaporation temperature may be 0 ° C. or lower and the drain water may freeze. On the other hand, as shown in FIG. 5B, the refrigerant flow path of the second switching valve 25 is throttled to reduce the refrigerant circulation amount and at the same time increase the evaporation pressure, thereby preventing excessive cooling capacity and drain water freezing. it can. Here, in the heating operation as well, there is a leakage at the closing angle and the heating capacity is lowered. Therefore, the rotation phase of the rotor 34 may be adjusted so that the indoor piping and the low-pressure piping are not connected.

  FIG. 6 shows a modification of the refrigerant flow path 33 formed in the rotor 34. As described above, the rotor 34 has a first through hole 45 formed in the radial direction and a first through hole 45 formed in a radial direction substantially orthogonal to the first through hole 45 and having a smaller hole diameter than the first through hole 45. Two through holes 46 are formed.

  By forming the refrigerant flow path 33 in this way, as shown in FIG. 6A, in the cooling / heating switching unit 20 for the indoor unit that performs the cooling operation during the cooling / heating simultaneous operation, the first through hole 45 allows the outdoor unit side. Thus, the refrigerant can be circulated through the low-pressure gas refrigerant pipe 19 with little pressure loss, and the refrigerant can continue to flow slightly from the high-pressure gas refrigerant pipe 18 on the outdoor unit side through the second through hole 46. In particular, by forming such a refrigerant flow path 33, it is not necessary to finely control the rotational phase of the rotor 34. Therefore, the simple switching control means 35 that omits the above-described gear mechanism and the like, and bypass This is useful because the refrigerant can be made to flow minutely without providing piping.

  Moreover, as shown in FIG.6 (b), at the time of external air low temperature cooling, the state similar to FIG.5 (b) can be formed by using the 2nd through-hole 46 in each switching valve. Furthermore, as shown in FIGS. 6C and 6D, it is possible to cope with the heating operation by controlling the rotation phase of the rotor 34.

  Instead of forming the second through hole 46 having a small hole diameter as in the present embodiment, the clearance of the rotor 34 itself is increased to provide a gap with the cylinder 32, and this gap is used. Then, the refrigerant may be slightly flowed. In addition, the refrigerant flow path 33 such as the first through hole 45 and the second through hole 46 is formed in a straight line in this embodiment, but is not limited thereto, and as a flow path that bends in the middle, Correspondingly, the low pressure gas refrigerant pipe 19 on the outdoor unit side, the high pressure gas refrigerant pipe 18 on the outdoor unit side, and the gas refrigerant pipe 17 on the indoor side may be connected.

  As described above, according to the present embodiment, the refrigerant flow path 33 is formed in the rotor 34 and the rotation control unit 35 controls the rotational phase of the rotor 34, thereby suppressing the size of the cooling / heating switching unit 20. Meanwhile, the pressure loss of the refrigerant can be reduced. Further, by controlling the rotation phase of the rotor 34 with the switching control means 35 finely, or by configuring the refrigerant flow path 33 with the first through hole 45 and the second through hole 46, without providing a bypass pipe, It is also possible to flow the refrigerant as small as necessary.

  Furthermore, since the mechanism generally used in the conventional piston type solenoid valve is a system that lifts the valve with the differential pressure across the solenoid valve, an extra pilot solenoid valve is required, and in the region where the flow of refrigerant is very small However, in this embodiment, the rotational force applied by the step motor to the rotor 34 is transmitted directly or indirectly using a gear mechanism or the like, so that it opens and closes regardless of the differential pressure. Is possible.

  Further, in the conventional piston type solenoid valve, when the solenoid valve is opened and closed, the refrigerant suddenly flows or the refrigerant flow is suddenly closed, so that the noise is loud. Since the refrigerant gradually flows along with the rotation, noise accompanying opening and closing of the switching valve can be suppressed.

  A second embodiment of the air conditioner of the present invention will be described. Since only the configuration of the cooling / heating switching unit 20 is different between the first embodiment and the second embodiment, description of other parts is omitted.

FIG. 7 is a diagram showing a configuration of the cooling / heating switching unit 20 according to the second embodiment of the present invention. In the present embodiment, unlike the first embodiment, the connection between the refrigerant pipes connected to each switching valve is switched by moving the rotor 34 in which the refrigerant flow path 33 is formed in the rotor axial direction. The rotor 34 moves in the axial direction of the rotor by an electromagnetic force generated by passing a current through the coil 50.
Fig.7 (a) is a figure which shows the longitudinal cross-section of the cooling / heating switching unit 20, and FIG.7 (b) is sectional drawing of the bb line | wire in Fig.7 (a). As shown in FIG. 7, in the cooling / heating switching unit 20 for the indoor unit 3 that performs the cooling operation in the state where the outdoor unit 2 performs the cooling and heating simultaneous operation, the refrigerant flow path formed in the rotor 34 of the first switching valve 24. The position of the rotor 34 in the axial direction is adjusted so that the area of the overlapping portion of 33 and the refrigerant pipe connected to the first switching valve 24 is reduced. On the other hand, in the second switching valve 25, the position of the rotor 34 in the axial direction is controlled so that the area of the overlapping portion is increased.

  As a result, the refrigerant can flow slightly through the first switching valve 24, and the refrigerant can flow through the second switching valve with little pressure loss. Further, at the time of low temperature cooling of the outside air, by controlling the position of the rotor 34 in the axial direction as shown in FIGS. 7C and 7D, a refrigerant flow path similar to that in FIG. 5B can be formed. Excessive cooling capacity and freezing can be prevented when the outside temperature is low.

  Thus, in the present embodiment, the refrigerant flow path can be opened or completely closed with little pressure loss in accordance with the movement of the rotor 34 in the rotor axial direction. By adjusting the area of the overlapping portion of 33 and the refrigerant pipe connected to the switching valve and adjusting the refrigerant flow rate, it is possible to prevent the refrigerant from being accumulated in the high-pressure gas refrigerant branch pipe without providing a bypass pipe. .

  FIG. 8 is a modification of the refrigerant flow path 33 formed in the rotor 34. The refrigerant flow path 33 has a first through hole 45 formed in the radial direction of the rotor 34, and a second hole having a hole diameter smaller than that of the first through hole formed at a position different from the first through hole 45 in the axial direction. The through-hole 46 is comprised. As shown in FIGS. 8A to 8D, adjusting the axial position of the rotor 34 as such a configuration also allows the refrigerant to flow in an open state in which the refrigerant flows with little pressure loss, as required. A slightly open state that allows a slight flow, and a closed state that completely blocks the refrigerant flow can be formed. Here, although two types of through holes are formed for each rotor 34, the present invention is not limited to this, and through holes having different hole diameters may be further increased.

  A third embodiment of the air conditioner of the present invention will be described. Since only the configuration of the cooling / heating switching unit 20 is different between the first embodiment and the third embodiment, description of other parts is omitted.

  Fig.9 (a) is a figure which shows the longitudinal cross-section of the cooling / heating switching unit 20 which concerns on 3rd Example of this invention. FIG. 9B to FIG. 9D are cross-sectional views taken along the line bb in FIG. 9A, and are diagrams illustrating states according to the operation status of each indoor unit. As shown in FIG. 9, in this embodiment, unlike the first embodiment, the switching valve is not provided in each of the high pressure gas refrigerant pipe 18 and the low pressure gas refrigerant pipe 19 on the outdoor unit side, but the gas on the indoor unit side is provided. One switching valve is provided at the junction of the refrigerant pipe 17, the high-pressure gas refrigerant pipe 18 on the outdoor unit side, and the low-pressure gas refrigerant pipe 19 (hereinafter referred to as three refrigerant pipes). That is, one switching valve to which three refrigerant pipes are connected is provided.

As shown in FIGS. 9B to 9D, the rotor 34 is formed so that about 1/2 is cut off at the height position where the three refrigerant pipes are connected. Becomes the refrigerant flow path 33. FIG. 9B shows the indoor unit in the heating operation, and the high-pressure gas refrigerant pipe 18 on the outdoor unit side and the indoor unit side are controlled by controlling the rotation phase of the rotor 34 as shown in FIG. 9B. Only the gas refrigerant pipe 17 of the indoor unit communicates, and the gas refrigerant pipe 17 of the indoor unit and the low pressure gas refrigerant pipe 19 of the outdoor unit do not communicate.
As shown in FIG. 9C, when the indoor unit is in cooling operation, only the gas refrigerant pipe 17 on the indoor unit side and the low-pressure gas refrigerant pipe 19 on the outdoor unit side communicate with each other, and the high-pressure gas refrigerant pipe on the outdoor unit side. The rotor 34 is rotated so that 18 and the gas refrigerant pipe 17 on the indoor unit side do not communicate with each other. The rotation angle at this time is 180 ° in the figure. Further, when the low-pressure gas refrigerant is caused to flow also through the high-pressure gas refrigerant pipe 18 on the outdoor unit side during the all-room cooling operation shown in FIG. 9D, the rotational phase of the rotor 34 is set so that all three refrigerant pipes communicate with each other. To control. The rotation angle at this time is 90 °.

  According to the present embodiment, since the refrigerant flow path 33 formed in the rotor 34 can be enlarged, the pressure loss when the refrigerant flows can be reduced as compared with the conventional piston type electromagnetic valve. Further, in the conventional method of switching the valve slide by using a high-low pressure differential pressure, such as a three-way valve and a four-way valve, a capillary for introducing high-low pressure and a pilot valve for switching the capillary are required. However, according to the configuration of the present embodiment, switching can be performed regardless of the differential pressure between high and low pressures, and the mechanism is simplified because neither a capillary nor a pilot valve is required.

  Further, similarly to the first embodiment, the rotational phase of the rotor 34 is finely controlled to adjust the area of the overlapping portion of the refrigerant flow path 33 and the three refrigerant pipes, thereby reducing the refrigerant to a small amount. It can also be shed. As a result, it is possible to prevent the accumulation of refrigerant in the high-pressure gas refrigerant branch pipe by omitting the bypass pipe as conventionally provided.

  Next, a first modification of the cooling / heating switching unit 20 of this embodiment will be described with reference to FIG. FIG. 10A is a diagram showing a longitudinal section of the cooling / heating switching unit 20, and FIGS. 10B, 10C, and 10D are sectional views taken along the line bb in FIG. 10A. Similarly, FIGS. 10 (e), (f), and (g) are cross-sectional views taken along the line ee, and FIGS. 10 (h), (i), and (j) are cross-sectional views taken along the line hh. In this modification, three refrigerant pipes are connected to the cylinder 32 at different positions in the rotor axial direction, and the refrigerant flow path 33 of the rotor 34 is formed corresponding to each refrigerant pipe. Refrigerant flow path 33 so that about 1/4 is cut off at a position corresponding to the high-pressure gas refrigerant pipe on the outdoor unit side and low-pressure gas refrigerant pipe on the outdoor unit side, and about 1/2 is cut off at a position corresponding to the gas refrigerant pipe on the indoor unit side. Is formed. The chipped surfaces are connected to each other in the height direction.

  When the indoor unit shown in FIGS. 10B, 10E, and 10H is in a heating operation, the high pressure gas refrigerant pipe 18 on the outdoor unit side and the gas refrigerant pipe 17 on the indoor unit side communicate with each other through the flow path 33. In addition, the rotational phase of the rotor 34 is controlled so that the gas refrigerant pipe 17 on the indoor unit side and the low-pressure gas refrigerant pipe 19 on the outdoor unit side do not communicate with each other. On the other hand, during the cooling operation, as shown in FIGS. 10C, 10 </ b> F, and 10 </ b> I, the rotor is arranged such that only the gas refrigerant pipe 17 on the indoor unit side and the low-pressure gas refrigerant pipe 19 on the outdoor unit side communicate with each other. The rotational phase of 34 is controlled. Further, during the all-room cooling operation, the rotational phase of the rotor 34 is controlled so that the three refrigerant pipes communicate with each other through the respective refrigerant flow paths 33 as shown in FIGS. 10 (d), 10 (g), and 10 (j). Further, the flow rate of the refrigerant can be arbitrarily controlled by finely controlling the rotation phase of the rotor 34 and adjusting the area of the overlapping portion of the refrigerant flow path 33 and the three refrigerant pipes.

  In this way, according to this modification, the three refrigerant pipes are connected to different positions in the height direction, and the refrigerant flow path 33 is formed in the rotor 34 corresponding to this, so that it is shown in FIG. The same operation as in the third embodiment is possible. Furthermore, in the third embodiment, the contact surface between the cylinder 32 and the rotor 33 is about ½ of the circumference, whereas in the present modification, the upper and lower parts extend to about 3/4 of the circumference. , Rotation operation is stable.

  FIG. 11 is a diagram illustrating a second modification of the cooling / heating switching unit 20 according to the third embodiment. As shown in FIG. 11A, in this modification, the high pressure gas refrigerant pipe 18 on the outdoor unit side and the low pressure gas refrigerant pipe 19 on the outdoor unit side are connected to the cylinder 32 at different positions in the rotor axial direction. . Here, the gas refrigerant pipe 17 on the indoor unit side can be connected to the cylinder 32 in a range from the connection position of the high-pressure gas refrigerant pipe 18 on the outdoor unit side to the connection position of the low-pressure gas refrigerant pipe 19 on the outdoor unit side. .

In this modified example, the function is the same as that of the modified example described above, but the rotor 34 is provided separately in the upper part and the lower part, and the switching control means 35 is provided corresponding to each rotor 34. Each of the upper and lower rotors 34 is formed so as to lack about ¼, and the lacked portion serves as the refrigerant flow path 33. FIG. 11 (b)
, (C) and (d) are cross sections taken along the line bb in FIG. 11 (a), and FIGS. 11 (e), (f) and (g) are cross sections taken along the line ee. When the indoor unit 3 is in the heating operation as shown in FIGS. 11B and 11E, the upper and lower rotors are connected so that only the high-pressure gas refrigerant pipe 18 on the outdoor unit side and the gas refrigerant pipe 17 on the indoor unit side communicate with each other. Each of the rotational phases of 34 is controlled. When the indoor unit is in cooling operation, the rotational phases of the upper and lower rotors 34 are controlled as shown in FIGS. 11 (d) and 11 (g), respectively, as shown in FIGS. 11 (c) and 11 (f). That's fine. Further, the flow rate of the refrigerant can be arbitrarily controlled as necessary by finely controlling the rotation phase of each rotor 34.

  As described above, according to this modification, the upper and lower rotors 34 are cut out by only about ¼, so that the rotational operation of the rotor 34 is more stable than the third embodiment and the first modification described above. To do. Furthermore, strength can be maintained and processing is easy.

It is a schematic diagram which shows the whole structure of the air conditioner of 1st Example. It is a figure which shows the structure of the 1st switching valve of 1st Example. It is a figure which shows the structure of the switching control means of 1st Example. It is a figure which shows the rotational phase control of the rotor of 1st Example. It is a figure which shows the rotational phase control of the rotor of 1st Example. It is a figure which shows the modification of the refrigerant | coolant flow path formed in the rotor of 1st Example. It is a figure which shows the structure of the cooling / heating switching unit of 2nd Example. It is a figure which shows the modification of the refrigerant | coolant flow path formed in the rotor of 2nd Example. It is a figure which shows the structure of the cooling / heating switching unit of 3rd Example. It is a figure which shows the 1st modification of the cooling / heating switching unit of 3rd Example. It is a figure which shows the 2nd modification of the cooling / heating switching unit of 3rd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air conditioner 2 Outdoor unit 3 Indoor unit 5 Compressor 7 Outdoor heat exchanger 14 Indoor heat exchanger 15 Indoor expansion valve 17 Gas refrigerant pipe 18 on the indoor unit side High-pressure gas refrigerant pipe 19 on the outdoor unit side Low pressure on the outdoor unit side Gas refrigerant pipe 20 Cooling / heating switching unit 24 First switching valve 25 Second switching valve 31 Connection port 32 Cylinder 33 Refrigerant flow path 34 Rotor 35 Switching control means 45 First through hole 46 Second through hole

Claims (3)

An refrigeration cycle is formed by connecting an outdoor unit having a compressor and an outdoor heat exchanger and a plurality of indoor units having an indoor heat exchanger and an indoor expansion valve to a pipe circulating the refrigerant. pedestal and the gas refrigerant pipe of the indoor unit side, with a heating and cooling switching unit and at least one connection to the outdoor unit side of the low-pressure gas refrigerant pipe and the high pressure gas refrigerant pipe switching the cooling and heating operations of the indoor units In air conditioner,
Wherein each heating and cooling switching unit, pre-outs scan refrigerant pipe, a front SL low-pressure gas refrigerant pipe and the high-pressure gas refrigerant pipe is cylindrical connection port to be connected is formed the cylinder, a cylindrical type cylinder Kiga scan refrigerant pipe before being fitted, before Symbol control and cylindrical rotor coolant flow path is formed to communicate with each other a low-pressure gas refrigerant pipe and the high-pressure gas refrigerant pipe, the rotational phase of the cylinder type rotor And an air conditioner characterized by comprising switching control means for switching between heating and cooling operations. In the cooling / heating switching unit, the gas refrigerant pipe, the low-pressure gas refrigerant pipe, and the high-pressure gas refrigerant pipe are connected to the cylinder at different positions in the axial direction of the rotor, and correspond to the refrigerant pipes. The air conditioner according to claim 1, wherein the refrigerant flow path of the rotor is formed . It said switching control means controls the rotational phase of the rotor, according to claim 1 or 2, characterized in that adjusting the area of the flow path wherein the respective pipes and the refrigerant passage is communicated with the overlap Air conditioner.

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