JP2013076377A - Control device of hermetic compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform control for eliminating any trouble associated with a novel constitution when controlling the operation of a hermetic compressor having the novel constitution for changing the contact state of a vane with an eccentric rotor, and the separate state of the vane from the eccentric rotor.SOLUTION: The control device of the hermetic compressor controls the hermetic compressor of the novel constitution which performs switching between a state that the vane is abutted on the eccentric rotor of a cylinder and a state that the vane is separated from the eccentric rotor by using a pressure difference between pressure in a casing and pressure in an accumulator. The control device compares the operational frequency of the hermetic compressor with a predetermined frequency, and compares an indoor or outdoor atmospheric temperature with a predetermined temperature, and further compares an operation elapsed time after the operational frequency of the hermetic compressor is equal to or higher than a predetermined frequency, and an atmospheric temperature is equal to or higher than a predetermined temperature. When the operation elapsed time is equal to or longer than the predetermined time, the connection state of a switching valve is switched.

Description

  Embodiments described herein relate generally to a control device for a hermetic compressor.

For example, a hermetic compressor for an air conditioner disclosed in Patent Document 1 is a hermetic compressor including two cylinders capable of compressing a refrigerant in a housing. In such a hermetic compressor, for example, the control of compressing the refrigerant by two cylinders is performed during normal operation, and the control of compressing the refrigerant by one cylinder is performed, for example, during the energy saving operation, that is, the refrigerant of one cylinder is compressed. Control to stop compression.
Here, the cylinder is configured so as to compress the refrigerant when the vane is in contact with the rotating eccentric rotor, and not compress the refrigerant when the vane is separated from the rotating eccentric rotor. Therefore, switching between the operation of compressing the refrigerant with two cylinders and the operation of compressing the refrigerant with one cylinder is realized by switching between the state where the vane is in contact with the eccentric rotor and the state where the vane is separated from the eccentric rotor. Has been. In this type of hermetic compressor, a new configuration is required to switch between a state where the vane is in contact with the eccentric rotor and a state where the vane is separated from the eccentric rotor, and the new configuration is adopted. Even if it does, the control apparatus which can control the hermetic type compressor without a malfunction is calculated | required.

JP 2010-48500 A

  Therefore, when controlling the operation of a hermetic compressor having a new configuration for switching between a state in which the vane is in contact with the eccentric rotor and a state in which the vane is separated from the eccentric rotor, Provided is a control device for a hermetic compressor capable of performing control that eliminates problems associated with the configuration.

  The control device for a hermetic compressor according to the present embodiment controls a hermetic compressor configured as follows. That is, the hermetic compressor includes a housing, a first cylinder, a second cylinder, a discharge port, a refrigerant pipe, an accumulator, a bypass pipe, and a switching valve. The housing has a refrigerant and lubricating oil inside. The first cylinder is provided in the housing, and is provided in a first cylinder chamber, a first eccentric rotor rotatably provided in the first cylinder chamber, and a reciprocating motion with respect to the first eccentric rotor, And the first vane always in contact with the first eccentric rotor, and the first eccentric rotor rotates while the first vane is always in contact with the first eccentric rotor. Compress. The second cylinder is provided in the housing, provided in a second cylinder chamber, a second eccentric rotor rotatably provided in the second cylinder chamber, and reciprocally movable with respect to the second eccentric rotor, And a second vane provided so as to be able to contact and be separated from the second eccentric rotor, and the second eccentric rotor rotates in a state where the second vane contacts the second eccentric rotor. When the refrigerant in the casing is compressed and the second vane is separated from the second eccentric rotor, the refrigerant in the casing is not compressed. The discharge port is provided in the housing and discharges a high-pressure refrigerant compressed by the first cylinder or by the first cylinder and the second cylinder. The refrigerant pipe connects the discharge port to the first cylinder and the second cylinder, and has a heat exchange part in the middle. The accumulator is provided on the downstream side of the heat exchange part in the refrigerant pipe, and the low-pressure refrigerant that has passed through the heat exchange part flows in. The bypass pipe has a base end connected to the housing. The switching valve includes a first connection state in which the tip of the bypass pipe is connected to a part of the refrigerant pipe downstream of the heat exchange unit and upstream of the accumulator, and the tip of the bypass pipe It switches to the 2nd connection state connected to a part upstream of a heat exchange part among refrigerant lines. In the first connection state, the second vane of the second cylinder is separated from the second eccentric rotor due to the pressure difference between the pressure in the housing and the pressure in the accumulator, and the lubricating oil in the housing passes through the bypass pipe. Flows into the accumulator. On the other hand, in the second connection state, a part of the high-pressure refrigerant flowing in the portion upstream of the heat exchange portion in the refrigerant pipe flows into the housing through the bypass pipe, whereby the second cylinder 2nd The vane contacts the second eccentric rotor, and the lubricating oil that has flowed into the accumulator in the first connected state is sucked into the housing by the suction force generated by the first cylinder and the second cylinder.

  The control device for the hermetic compressor of the present embodiment, when controlling the operation of the hermetic compressor configured as described above, uses the operating frequency comparison means to determine the operating frequency and the predetermined frequency of the hermetic compressor. And the indoor or outdoor atmospheric temperature is compared with a predetermined temperature by the temperature comparison means. The operation elapsed time comparing means compares the operation elapsed time of the hermetic compressor that has elapsed after the operating frequency of the hermetic compressor is equal to or higher than the predetermined frequency and the ambient temperature is equal to or higher than the predetermined temperature with the predetermined time. When the operation elapsed time becomes equal to or longer than the predetermined time, the switching valve control means switches the switching valve from the first connection state to the second connection state.

The figure which shows the structure of the hermetic compressor of the air conditioner which concerns on one Embodiment, and shows a 1st connection state. FIG. 1 equivalent view showing the second connection state Cross-sectional plan view showing the configuration of the first cylinder Cross-sectional plan view showing the configuration of the second cylinder Flow chart showing control contents when switching compression mode Block diagram schematically showing the configuration of the air conditioner

  Hereinafter, an embodiment in which this embodiment is applied to a control device that controls the operation of a hermetic compressor of an air conditioner will be described with reference to the drawings. As shown in FIG. 6, the air conditioner 100 includes an indoor unit 201 and an outdoor unit 301. The indoor unit 201 includes a control unit 202 that controls the overall operation of the indoor unit 201, a reception unit 203, a transmission unit 204, a drive circuit 205, and the like connected to the control unit 202. The user can input various types of information such as an operation course and set temperature via the remote controller 206, and the control unit 202 of the indoor unit 201 receives various types of information input from the remote controller 206. The received information is supplied to the transmission unit 204 and the drive circuit 205. The transmission unit 204 transmits the given information to the outdoor unit 301. The drive circuit 205 drives the indoor fan 207 based on the given information. The indoor unit 201 includes an indoor temperature sensor 208.

  The outdoor unit 301 includes a control unit 302 that controls the overall operation of the outdoor unit 301, a receiving unit 303 connected to the control unit 302, an outdoor temperature sensor 304, various drive circuits 305 to 309, and the like. The control unit 302 of the outdoor unit 301 receives various types of information from the indoor unit 201 via the receiving unit 303 and gives the received information to the drive circuits 305 to 309. The drive circuit 305 drives the hermetic compressor 10. That is, the control unit 302 corresponds to a control device of the present invention that controls the operation of the hermetic compressor 10 via the drive circuit 305. As will be described in detail later, the operating frequency of the hermetic compressor 10 is controlled. The operating frequency comparison means of the present invention for comparing a predetermined frequency with a temperature comparison means of the present invention for comparing an indoor or outdoor ambient temperature with a predetermined temperature, and the operating frequency of the hermetic compressor 10 is equal to or higher than a predetermined frequency, and The operation elapsed time comparison means for comparing the operation elapsed time of the hermetic compressor 10 that has elapsed since the ambient temperature has become equal to or higher than the predetermined temperature with the predetermined time, and when the operation elapsed time is equal to or greater than the predetermined time. The switching valve 17 described later has a function as a switching valve control means for switching the switching valve 17 from the first connection state to the second connection state. The drive circuit 306 drives the four-way valve 310. The drive circuit 307 drives a throttle valve 51c of the heat exchange unit 51 described later. The drive circuit 308 drives a switching valve 17 described later. The drive circuit 309 drives the outdoor fan 311.

Next, the configuration of the hermetic compressor 10 included in the air conditioner 100 will be described in detail. As shown in FIG. 1 and FIG. 2, the hermetic compressor 10 of the air conditioner 100 includes a housing 11, a plurality of, in this case, two cylinders, a first cylinder 12 and a second cylinder 13, and a refrigerant pipe. 14, an accumulator 15, a bypass line 16, and a switching valve 17.
The housing 11 is made of a sealed container-like member and constitutes the main body of the hermetic compressor 10. The housing 11 has a refrigerant and lubricating oil. Further, the casing 11 is provided with a discharge port 11a for discharging a high-pressure refrigerant compressed by the first cylinder 12 or by both the first cylinder 12 and the second cylinder 13 as will be described in detail later. It has been.

  Both the first cylinder 12 and the second cylinder 13 are provided at the bottom inside the housing 11. Among these, the first cylinder 12 includes a first cylinder chamber 21, a first eccentric rotor 22, and a first vane 23. The first cylinder chamber 21 is a hollow member, and includes a suction port 21a, a discharge port 21b, and a vane accommodating portion 21c shown in FIG. In this case, the suction port 21a and the discharge port 21b communicate the inside and the outside of the first cylinder chamber 21, but the vane housing portion 21c is open on the inside and closed on the outside. The first eccentric rotor 22 is rotatably provided in the first cylinder chamber 21. The first eccentric rotor 22 has a rotating shaft 31 attached at a position deviated from the center. The rotating shaft 31 is rotationally driven by a driving unit (not shown) provided in the housing 11. The first vane 23 is accommodated in the vane accommodating portion 21c of the first cylinder chamber 21, and is provided so as to be capable of reciprocating with respect to the first eccentric rotor 22, as indicated by an arrow a in FIG. The first vane 23 is urged toward the rotating shaft 31 of the first eccentric rotor 22 by an urging member including, for example, a spring 32.

  When the first vane 23 is in contact with the first eccentric rotor 22, the inside of the first cylinder chamber 21 is divided into two spaces by the first vane 23. By rotating the first eccentric rotor 22 in this state, the refrigerant in the first cylinder chamber 21 is compressed, and the compressed refrigerant is discharged into the housing 11 from the discharge port 21b of the first cylinder chamber 21. . The first cylinder 12 is configured such that the first vane 23 always abuts on the first eccentric rotor 22 by the urging force of the spring 32. Therefore, the first vane 23 is not separated from the first eccentric rotor 22.

  In this case, the second cylinder 13 is provided below the first cylinder 12 and includes a second cylinder chamber 41, a second eccentric rotor 42, and a second vane 43. The second cylinder chamber 41 is a hollow member and has a suction port 41a, a discharge port 41b, and a back pressure port 41c shown in FIG. In this case, the suction port 41a, the discharge port 41b, and the back pressure port 41c all communicate with the inside and the outside of the second cylinder chamber 41. The second eccentric rotor 42 is rotatably provided in the second cylinder chamber 41. The second eccentric rotor 42 is attached with the rotation shaft 31 common to the first eccentric rotor 22 at a position deviated from the center. In this case, the second eccentric rotor 42 is attached such that the eccentric direction is different from the direction in which the first eccentric rotor 22 is eccentric. The second vane 43 is accommodated in the back pressure port 41c of the second cylinder chamber 41 and is provided so as to be capable of reciprocating with respect to the second eccentric rotor 42 as indicated by an arrow b in FIG. That is, the back pressure port 41 c has a function as a vane accommodating portion that accommodates the second vane 43 in addition to the function of discharging the pressure in the housing 11 as described later.

  In a state where the second vane 43 is in contact with the second eccentric rotor 42, the inside of the second cylinder chamber 41 is divided into two spaces by the second vane 43. When the second eccentric rotor 42 rotates in this state, the refrigerant in the second cylinder chamber 41 is compressed, and the compressed refrigerant is discharged into the housing 11 from the discharge port 41b of the second cylinder chamber 41. . The inside of the housing 11 is maintained at a high pressure by the pressure of the refrigerant discharged from both the first cylinder 12 and the second cylinder 13 in this way. On the other hand, in the state where the second vane 43 is separated from the second eccentric rotor 42, the inside of the second cylinder chamber 41 is not divided into two spaces by the second vane 43, but becomes one space. Even if the second eccentric rotor 42 rotates in this state, the rotation is idle, so that the refrigerant in the second cylinder chamber 41 is not compressed. Therefore, at this time, the pressure in the housing 11 is slightly reduced.

  The refrigerant pipe 14 connects between the discharge port 11 a of the housing 11 and the suction port 21 a of the first cylinder 12 and the suction port 41 a of the second cylinder 13. A heat exchanging portion 51 that constitutes the air conditioner 100 is provided in the middle of the refrigerant pipe 14. The heat exchanging unit 51 includes a condenser 51a, an evaporator 51b, and a throttle valve 51c provided between the condenser 51a and the evaporator 51b.

  The accumulator 15 is made of a sealed container-like member, is located on the side of the housing 11, and is provided on the downstream side of the heat exchanger 51 in the refrigerant pipe 14. The low-pressure refrigerant that has passed through the heat exchange part 51 of the refrigerant pipe 14 flows into the accumulator 15. Inside the accumulator 15, an intake refrigerant pipe 14 a that constitutes the most downstream portion that is a part of the refrigerant pipe 14 extends, and a portion of the intake refrigerant pipe 14 a near the bottom of the accumulator 15 is disposed in the accumulator 15. A lubricating oil return hole 14b is formed. The accumulator 15 configured in this manner gas-liquid separates the refrigerant flowing in from the refrigerant pipe 14 and discharges the gasified refrigerant from the suction refrigerant pipe 14a. As a result, the refrigerant that has not been gasified remains in the accumulator 15, and the refrigerant is prevented from being sucked into the housing 11 in a liquid state.

The bypass line 16 is a line different from the refrigerant line 14, and the back end pressure of the second cylinder chamber 41 of the second cylinder 13 described above passes through the lower end of the side part of the casing 11. It is connected to the mouth 41c.
The switching valve 17 is provided at the tip of the bypass pipe line 16 and has a first connection port 17a at the upper part and a second connection port 17b and a third connection port 17c at the lower part. Connected to the first connection port 17a is an upstream branch refrigerant pipe 14c branched from a portion of the refrigerant pipe 14 upstream of the heat exchange section 51. Connected to the second connection port 17b is a downstream branch refrigerant pipe 14d that branches from a portion of the refrigerant pipe 14 that is downstream of the heat exchange section 51 and upstream of the accumulator 15. The distal end portion of the bypass conduit 16 is connected to the third connection port 17c.

  The switching valve 17 is switched between a first communication state shown in FIG. 1 and a second communication state shown in FIG. In the first communication state, the second connection port 17b and the third connection port 17c communicate with each other. On the other hand, in the second communication state, the first connection port 17a and the third connection port 17c are in communication. The switching valve 17 switched to the first communication state switches the pipeline configuration of the hermetic compressor 10 to the first connection state shown in FIG. In the first connection state, the tip of the bypass pipe 16 is located downstream of the heat exchanger 51 and upstream of the accumulator 15 in the refrigerant pipe 14 via the downstream branch refrigerant pipe 14d. Connect to the part. Moreover, the switching valve 17 switched to the 2nd communication state switches the pipe line structure of the hermetic compressor 10 to the 2nd connection state shown in FIG. In the second connection state, the tip end portion of the bypass pipe line 16 is connected to a part of the refrigerant pipe line 14 upstream of the heat exchange part 51 via the upstream branch refrigerant pipe line 14c.

  In the hermetic compressor 10 of the air conditioner 100 configured as described above, the control unit 302 of the outdoor unit 301 sets the hermetic compressor 10 to 1 when the air conditioner 100 performs an energy saving operation, for example. Operate in cylinder operation mode. The one-cylinder operation mode is an operation mode in which the compression of the refrigerant by the second cylinder 13 is stopped and the refrigerant is compressed by one first cylinder 12. In the one-cylinder operation mode, the hermetic compressor 10 switches its pipeline configuration to the first connection state shown in FIG.

  In the first connection state, the inside of the housing 11 where the high-pressure refrigerant exists is connected to the accumulator 15 where the low-pressure refrigerant exists via the bypass conduit 16 connected to the back pressure port 41 c of the second cylinder 13. Connected inside. Therefore, a pressure difference between the inside of the high pressure housing 11 and the inside of the low pressure accumulator 15 causes the pressure in the housing 11 to flow from the back pressure port 41 c of the second cylinder 13 through the bypass conduit 16 into the accumulator 15. As a result, a suction force is applied to the bypass conduit 16 in the direction indicated by the arrow A in FIG. 1, that is, in the direction from the high pressure housing 11 to the low pressure accumulator 15. Will occur. Due to this suction force, the second vane 43 accommodated in the back pressure port 41c of the second cylinder 13 is sucked toward the bypass pipe line 16 side, that is, radially outward, from the second eccentric rotor 42. Separate. As a result, the refrigerant is not compressed in the second cylinder 13, and accordingly, the heat exchange operation in the heat exchanging portion 51 is suppressed and the energy saving operation is performed.

  However, when the hermetic compressor 10 is operated in the one-cylinder operation mode as described above, that is, when the hermetic compressor 10 is operated in the first connection state, as described above, the bypass line 16 In addition, a suction force is generated in a direction from the high pressure casing 11 toward the low pressure accumulator 15. Therefore, this suction force causes the lubricating oil in the housing 11 to flow into the accumulator 15 via the bypass conduit 16, and the lubricating oil in the housing 11 may be insufficient. Here, the cylinders 12 and 13 in the housing 11 need to be maintained in a state of being immersed in lubricating oil in order to ensure the durability and reliability thereof. Therefore, in the present embodiment, when the hermetic compressor 10 is operated in the one-cylinder operation mode, the pipeline configuration is switched to the second connection state under a predetermined condition, and as a result, the accumulator is operated as described above. The lubricating oil that has flowed into 15 is collected in the housing 11.

  That is, in the second connection state shown in FIG. 2, the inside of the housing 11 is not connected to the low-pressure accumulator 15, but is connected to the high-pressure refrigerant via the bypass pipe 16 and the upstream branch refrigerant pipe 14c. Is connected to the upstream side of the refrigerant pipe 14 through which the refrigerant flows. Therefore, a part of the high-pressure refrigerant flowing through the refrigerant pipe 14 flows in the direction indicated by the arrow B in FIG. 2, and the second cylinder in the housing 11 via the upstream branch refrigerant pipe 14 c and the bypass pipe 16. 13 starts to flow. Accordingly, the second vane 43 accommodated in the back pressure port 41 c of the second cylinder 13 is pushed into the second eccentric rotor 42 side, that is, radially inward, and comes into contact with the second eccentric rotor 42. As a result, the refrigerant in the casing 11 is compressed by the two cylinders 12 and 13. That is, the hermetic compressor 10 is driven in the two-cylinder operation mode. With the compression operation by these two cylinders 12 and 13, a suction force is generated in the direction indicated by the arrow C in FIG. Due to this suction force, the lubricating oil that has flowed into the accumulator 15 in the first connection state is sucked into the housing 11 via the suction refrigerant pipe 14a, whereby the lubricating oil in the accumulator 15 is sucked. Can be recovered in the housing 11.

Next, the control contents when switching between the 1-cylinder operation mode and the 2-cylinder operation mode in the hermetic compressor 10 having the above-described configuration will be described with reference to FIG.
That is, when the air conditioner 100 is powered on, the control unit 302 of the outdoor unit 301 normally operates the hermetic compressor 10 in the two-cylinder operation mode (step S1). However, for example, when the energy-saving operation is set in the air conditioner 100 (step S2: YES), the control unit 302 switches the pipeline configuration of the hermetic compressor 10 to the first connected state by the switching valve 17 (step S2). S3) The hermetic compressor 10 is operated in the one-cylinder operation mode (step S4).

  The air conditioner 100 includes an indoor temperature sensor 208 shown in FIG. 6 that detects the temperature of the room in which the indoor unit 201 is installed, and an outdoor temperature sensor 304 shown in FIG. 6 that detects the outdoor temperature. During operation, the outdoor temperature sensor 304 detects the outdoor temperature, compares the outdoor temperature detected by the outdoor temperature sensor 304 with the set temperature set in the air conditioner 100, and during the heating operation, The temperature of the room is detected by the temperature sensor 208, and the room temperature detected by the room temperature sensor 208 is compared with the set temperature set in the air conditioner 100. Based on the comparison result during each operation. The operation is performed while adjusting the operation frequency of the hermetic compressor 10.

  Then, when the operation of the hermetic compressor 10 in the one-cylinder operation mode is started, the control unit 302 determines whether or not the operating frequency of the hermetic compressor 10 is equal to or higher than the predetermined frequency H (step S5). To do. The process of step S5 corresponds to the operating frequency comparison means of the present invention. The predetermined frequency H is set to, for example, 10.8 Hz during the cooling operation, and is set to, for example, 18.0 Hz during the heating operation.

  Further, when the operation of the hermetic compressor 10 in the one-cylinder operation mode is started, the control unit 302 determines whether or not the outdoor ambient temperature has become equal to or higher than the predetermined temperature Tc during the cooling operation, It is determined whether or not the ambient temperature has become equal to or higher than a predetermined temperature Th (step S6). The process of step S6 corresponds to the temperature comparison means of the present invention. The predetermined temperature Tc during the cooling operation is set to 32 ° C., for example, and the predetermined temperature Th during the heating operation is set to 20 ° C., for example. In the control unit 302, the operation frequency of the hermetic compressor 10 is equal to or higher than the predetermined frequency H (step S5: YES), and the outdoor atmospheric temperature is higher than the predetermined temperature Tc during the cooling operation, or during the heating operation. When the indoor atmospheric temperature is equal to or higher than the predetermined temperature Th (step S6: YES), counting by a timer (not shown) is started, and the count value, that is, the operating frequency of the hermetic compressor 10 is equal to or higher than the predetermined frequency H. And the operation elapsed time of the hermetic compressor 10 that has elapsed since the outdoor temperature is equal to or higher than the predetermined temperature Tc during the cooling operation or the indoor temperature is equal to or higher than the predetermined temperature Th during the heating operation. It is determined whether or not the above has been reached (step S7). The process of step S7 corresponds to the operation elapsed time comparison means of the present invention. The predetermined time C is set to 60 minutes, for example.

  When the operation frequency of the hermetic compressor 10 becomes lower than the predetermined frequency H before the count value by the timer becomes equal to or longer than the predetermined time C (step S7: NO), the control unit 302 (step S5: NO) Alternatively, when the outdoor temperature becomes lower than the predetermined temperature Tc during the cooling operation, or when the indoor temperature becomes lower than the predetermined temperature Th during the heating operation (step S6: NO), a timer is used. The count value is reset (step S8) and the one-cylinder operation mode is continued (step S4). On the other hand, when the count value by the timer becomes equal to or longer than the predetermined time C (step S7: YES), the control unit 302 changes the pipeline configuration of the hermetic compressor 10 from the first connection state to the second state by the switching valve 17. Switching to the connected state (step S9), the hermetic compressor 10 is operated in the two-cylinder operation mode (step S10). The processing in step S9 corresponds to the switching valve control means of the present invention. The control unit 302 repeatedly executes the above control until the power of the air conditioner 100 is turned off.

  The control device for a hermetic compressor according to one embodiment described above controls a hermetic compressor configured as follows. That is, the hermetic compressor includes a housing, a first cylinder, a second cylinder, a discharge port, a refrigerant pipe, an accumulator, a bypass pipe, and a switching valve. The housing has a refrigerant and lubricating oil inside. The first cylinder is provided in the housing, and is provided in a first cylinder chamber, a first eccentric rotor rotatably provided in the first cylinder chamber, and a reciprocating motion with respect to the first eccentric rotor, And the first vane always in contact with the first eccentric rotor, and the first eccentric rotor rotates while the first vane is always in contact with the first eccentric rotor. Compress. The second cylinder is provided in the housing, provided in a second cylinder chamber, a second eccentric rotor rotatably provided in the second cylinder chamber, and reciprocally movable with respect to the second eccentric rotor, And a second vane provided so as to be able to contact and be separated from the second eccentric rotor, and the second eccentric rotor rotates in a state where the second vane contacts the second eccentric rotor. When the refrigerant in the casing is compressed and the second vane is separated from the second eccentric rotor, the refrigerant in the casing is not compressed. The discharge port is provided in the housing and discharges a high-pressure refrigerant compressed by the first cylinder or by the first cylinder and the second cylinder. The refrigerant pipe connects the discharge port to the first cylinder and the second cylinder, and has a heat exchange part in the middle. The accumulator is provided on the downstream side of the heat exchange part in the refrigerant pipe, and the low-pressure refrigerant that has passed through the heat exchange part flows in. The bypass pipe has a base end connected to the housing. The switching valve includes a first connection state in which the tip of the bypass pipe is connected to a part of the refrigerant pipe downstream of the heat exchange unit and upstream of the accumulator, and the tip of the bypass pipe It switches to the 2nd connection state connected to a part upstream of a heat exchange part among refrigerant lines. In the first connection state, the second vane of the second cylinder is separated from the second eccentric rotor due to the pressure difference between the pressure in the housing and the pressure in the accumulator, and the lubricating oil in the housing passes through the bypass pipe. Flows into the accumulator. On the other hand, in the second connection state, a part of the high-pressure refrigerant flowing in the portion upstream of the heat exchange portion in the refrigerant pipe flows into the housing through the bypass pipe, whereby the second cylinder 2nd The vane contacts the second eccentric rotor, and the lubricating oil that has flowed into the accumulator in the first connected state is sucked into the housing by the suction force generated by the first cylinder and the second cylinder.

  The control device for the hermetic compressor of the present embodiment, when controlling the operation of the hermetic compressor configured as described above, uses the operating frequency comparison means to determine the operating frequency and the predetermined frequency of the hermetic compressor. And the indoor or outdoor atmospheric temperature is compared with a predetermined temperature by the temperature comparison means. The operation elapsed time comparing means compares the operation elapsed time of the hermetic compressor that has elapsed after the operating frequency of the hermetic compressor is equal to or higher than the predetermined frequency and the ambient temperature is equal to or higher than the predetermined temperature with the predetermined time. When the operation elapsed time becomes equal to or longer than the predetermined time, the switching valve control means switches the switching valve from the first connection state to the second connection state.

  The configuration of the hermetic compressor 10 of the present embodiment is such that the state in which the second vane is in contact with the second eccentric rotor of the second cylinder and the state in which the second vane is separated from the second eccentric rotor are the pressure in the housing. It is the structure switched using the pressure difference between the pressure in the accumulator, that is, the new structure switched using the back pressure from the housing to the accumulator. And according to the control apparatus of the hermetic compressor of this embodiment, the trouble with the new configuration of the hermetic compressor, that is, the lubricating oil in the casing also accompanies the back pressure from the casing to the accumulator. It is possible to perform control that solves the problem of inflow and lack of lubricating oil in the housing.

Note that the present embodiment can also be applied to a control device that controls the operation of a hermetic compressor including two or more cylinders. In that case, the hermetic compressor may be configured to reciprocate at least one of the cylinder vanes using back pressure from the housing to the accumulator.
In the switching control between the 1-cylinder operation mode and the 2-cylinder operation mode, the predetermined frequency H, the predetermined temperature Tc, the predetermined temperature Th, and the predetermined time C can be set to appropriate values.
The control device of the present embodiment may be configured by a control device on the indoor unit side, and the operation of the hermetic compressor provided on the outdoor unit side may be controlled remotely.
The condition for switching between the 2-cylinder operation mode and the 1-cylinder operation mode is not limited to the case where the energy saving operation is set in the air conditioner, and various conditions can be set.

The present embodiment can be applied not only to a control device that controls the operation of a hermetic compressor of an air conditioner, but also to a control device that controls the operation of another hermetic compressor.
This embodiment is presented as an example and is not intended to limit the scope of the invention. The novel embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. This embodiment and its modifications 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, 10 is a hermetic compressor of an air conditioner, 11 is a housing, 11a is a discharge port, 12 is a first cylinder, 13 is a second cylinder, 14 is a refrigerant line, 15 is an accumulator, and 16 is a bypass pipe. Path, 17 is a switching valve, 21 is a first cylinder chamber, 22 is a first eccentric rotor, 23 is a first vane, 41 is a second cylinder chamber, 42 is a second eccentric rotor, 43 is a second vane, and 51 is heat. An exchange unit, 100 is an air conditioner, and 302 is a control unit (control device).

Claims (1)

A housing having refrigerant and lubricating oil inside,
A first cylinder chamber; a first eccentric rotor rotatably provided in the first cylinder chamber; a reciprocating motion with respect to the first eccentric rotor; A first vane always in contact with one eccentric rotor, and the first eccentric rotor rotates in a state where the first vane is always in contact with the first eccentric rotor, whereby the refrigerant in the casing is A first cylinder for compression;
A second cylinder chamber, a second eccentric rotor rotatably provided in the second cylinder chamber, a reciprocating movement with respect to the second eccentric rotor, and the second cylinder chamber; A second vane that can be brought into contact with and separated from the eccentric rotor, and the second eccentric rotor rotates in a state in which the second vane is in contact with the second eccentric rotor. A second cylinder that compresses the refrigerant in the body and does not compress the refrigerant in the housing in a state where the second vane is separated from the second eccentric rotor;
A discharge port that is provided in the housing and discharges the high-pressure refrigerant compressed by the first cylinder or by the first cylinder and the second cylinder;
A refrigerant line connecting the discharge port with the first cylinder and the second cylinder, and having a heat exchange part in the middle;
An accumulator that is provided downstream of the heat exchange part in the refrigerant pipe and into which the low-pressure refrigerant that has passed through the heat exchange part flows;
A bypass conduit having a proximal end connected to the housing;
A first connection state in which the tip of the bypass pipe is connected to a portion of the refrigerant pipe that is downstream of the heat exchange unit and upstream of the accumulator; and the tip of the bypass pipe A switching valve for switching to a second connection state in which the refrigerant pipe is connected to a portion upstream of the heat exchange unit,
With
In the first connection state, the second vane of the second cylinder is separated from the second eccentric rotor due to a pressure difference between the pressure in the casing and the pressure in the accumulator, and the lubrication in the casing is performed. Oil flows into the accumulator via the bypass line,
In the second connection state, a part of the high-pressure refrigerant flowing in a portion upstream of the heat exchanging portion of the refrigerant pipe flows into the casing through the bypass pipe, thereby The second vanes of two cylinders abut against the second eccentric rotor, and the lubricating oil that has flowed into the accumulator in the first connected state is generated by the first cylinder and the second cylinder. A control device for controlling a hermetic compressor of an air conditioner configured to be sucked into the casing by
An operating frequency comparing means for comparing the operating frequency of the hermetic compressor with a predetermined frequency;
Temperature comparison means for comparing the indoor or outdoor ambient temperature with a predetermined temperature;
The operation elapsed time for comparing the operation elapsed time of the hermetic compressor with a predetermined time after the operation frequency of the hermetic compressor is equal to or higher than the predetermined frequency and the ambient temperature is equal to or higher than the predetermined temperature. A comparison means;
A switching valve control means for switching the switching valve from the first connection state to the second connection state when the operation elapsed time is equal to or longer than the predetermined time;
A control device for a hermetic compressor, comprising:

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