JPH04365992A - Coolant circuit of multiple type compressor - Google Patents

Abstract

PURPOSE:To avoid generating impact and thus generating excessive load due to oil compression or to difference in pressure in a coolant circuit of a multicylinder compressor, in a state where a normal use side compressor is driven, when a maneuvering side compressor is started to be driven in order to improve performance. CONSTITUTION:An electromagnetic valve 64 is put between a discharging port 37 and a suction port 39 of a maneuvering side compressor C2, while a liquid sealing protruded surface 57 of the maneuvering compressor C2 is smaller than a liquid sealing protruded surface 55 of a normal use side compressor C1, and an electromagnetic valve 65 is put between the discharging port 37 and the suction port.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an engine heat pump that uses an engine to drive a compressor for heating and cooling, and also utilizes the exhaust heat of the engine for heating.
The present invention relates to a multiple compressor type refrigerant circuit.

0002

2. Description of the Related Art Conventionally, in an engine heat pump mechanism, a technique relating to a refrigerant circuit of a multi-type compressor in which a plurality of compressors are arranged and a plurality of indoor units and outdoor units are arranged is known. For example, JP-A-2-16
This is similar to the technique described in Japanese Patent No. 1265.

0003

[Problem to be solved by the invention] Conventionally, in the refrigerant circuit of a multi-type compressor, in order to control the capacity, only the regular compressor C1 of the two units is often operated, and the heating and cooling capacity is increased in the middle. , the start/stop side compressor C
2 clutch is turned on. However, when the clutch of the start/stop side compressor C2 is turned on, oil that has entered the cylinder of the compressor while the engine is stopped may be compressed, resulting in an excessive load on the start/stop side compressor C2. The present invention relates to a technique for preventing the generation of a load that occurs when the drive of the start/stop side compressor C2 is started.

0004

[Means for Solving the Problems] The problems to be solved by the present invention are as described above, and next, the means for solving the problems will be explained. That is, in a refrigerant circuit of a multi-type compressor that includes a regular-use compressor C1 and a starting/stopping compressor C2, a check valve is provided in the suction line on the side of the starting/stopping compressor C2, and a check valve is provided on the downstream side of the check valve and the discharge line. A refrigerant circuit is provided to communicate with the refrigerant circuit, and a solenoid valve is provided in the refrigerant circuit. In addition, in the refrigerant circuit of a multi-type compressor that includes a regular-use compressor C1 and a start/stop side compressor C2, the chattering characteristics of the regular-use compressor C1 are as follows.
It is assumed that the vanes can follow the cylinder wall surface only by the centrifugal force of the vanes even in a state where there is no difference in refrigerant pressure. It can follow the cylinder wall surface. In addition, in a refrigerant circuit of a multi-type compressor including a regular use side compressor C1 and a start/stop side compressor C2, a check valve is provided in the discharge line of the compressor, and the intermediate part between the discharge port and the check valve is connected to the compressor suction line. A refrigerant passage is provided to communicate with the refrigerant passage, and a solenoid valve is provided in the middle of the refrigerant passage.

[0005]

[Operation] Next, the operation will be explained. In the case of claim 1, immediately before the start/stop side compressor C2 is driven, the solenoid valve 64
opens and supplies the pressure from the discharge port 37 to the suction port 39, pushing out the oil in the cylinder. In the case of claim 2, the liquid seal protrusion surface 57 of the start/stop side compressor C2 is replaced with the liquid seal protrusion surface 5 of the regular use side compressor C1.
By making it smaller than 5, chattering is actively generated to create an escape route for the oil when compressing the oil. In the case of claim 3, by opening the solenoid valve 65, the pressure gas of the discharge port 37 is supplied to the suction sides of the regular side compressor C1 and the start/stop side compressor C2, so that there is no pressure difference. This is to avoid impact when the start/stop side compressor C2 starts driving.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a refrigerant circuit diagram of an engine heat pump device in which one engine 1 drives two compressors, a regular-use compressor C1 and a start/stop compressor C2. Figure 1
In this section, the configuration and the flow of refrigerant during cooling will be explained. The engine 1 drives two compressors, a regular side compressor C1 and a start/stop side compressor C2. Since the two refrigerant circuits are symmetrical left and right, the refrigerant circuit of the regular-use compressor C1 will be explained. The engine 1 drives the compressor C1 on the regular side, converts the refrigerant into high-temperature, high-pressure superheated steam, passes through an oil separator 4, and separates oil. The oil after separation passes through the oil return pipe 44 to the regular side compressor C.
Return to 1.

After the oil has been separated, the refrigerant in the high temperature and high pressure superheated vapor state is guided to the four-way switching valve 6, and from the four-way switching valve 6, it is passed through a pipe passing through the exhaust heat recovery device 10, and then is sent to the outside. It passes through the heat exchanger 18. A defrosting expansion valve 16 is disposed between the exhaust heat recovery device 10 and the indoor heat exchanger 18,
A solenoid valve 12 and a check valve 14 for switching to defrosting action are arranged in parallel. 48 is a temperature-sensitive cylinder for defrosting, and 50 is a temperature-sensitive cylinder for heating.

Next, while passing through the outdoor heat exchanger 18, the refrigerant is converted from a high-temperature, high-pressure superheated vapor state to a high-pressure liquid state, and when the vapor is condensed into gas, heat is transferred from the refrigerant to the atmosphere. It releases it. The high-pressure liquid refrigerant that has passed through the outdoor heat exchanger 18 passes through the check valve 32 without passing through the heating expansion valve 22, and enters the liquid receiver 20 via the filter 26. 30 is a check valve that opens and closes during defrosting. In the liquid receiver 20, the refrigerant in the gas phase is separated, and only the refrigerant in the high-pressure liquid state is supplied to the cooling expansion valve 24 through the filter 28.

In the cooling expansion valve 24, the refrigerant rapidly expands, and the high-pressure liquid refrigerant becomes a low-temperature, low-pressure vapor state, passes through the liquid line closing valve 36, and then enters the indoor heat exchanger 40. During the passage, the refrigerant absorbs the heat in the room, and the low-temperature, low-pressure refrigerant turns into superheated steam and returns to the four-way switching valve 6 via the gas line closing valve 38. The refrigerant enters the accumulator 8 through the four-way switching valve 6, and after completely converting the refrigerant into a gas phase, it is returned to the regular side compressor C1. This cycle is repeated to cool the room.

Next, the flow of refrigerant in heating will be explained. In this case, the four-way switching valve 6 is switched from cooling to heating. A high-temperature, high-pressure superheated vapor refrigerant is also discharged from the regular-use compressor C1 driven by the engine 1, and enters the oil separator 4, where the oil is separated and the refrigerant is in a high-temperature, high-pressure superheated vapor state. The refrigerant passes from the four-way switching valve 6 through the gas line closing valve 38 and reaches the indoor heat exchanger 40.

In the indoor heat exchanger 40, heat is released from the high-temperature, high-pressure superheated vapor state refrigerant to the indoor air, and the refrigerant becomes a high-pressure liquid state. The refrigerant in the high-pressure liquid state passes through the check valve 34 from the liquid line closing valve 36 to the liquid receiver 2 without passing through the cooling expansion valve 24.
0, the gas phase refrigerant is separated by the liquid receiver 20, and only the liquid phase refrigerant passes through the filter 26, which does not pass through the defrosting solenoid valve 30 or the check valve 32, and then passes through the heating expansion valve 22. be. In the heating expansion valve 22, the refrigerant in a high-pressure liquid state rapidly expands to become a low-temperature, low-pressure vapor state, and while passing through the outdoor heat exchanger 18, it obtains heat from the outside air and becomes superheated vapor.

[0012] At this time, if the temperature of the outside air is low and it is not possible to obtain enough heat to turn the steam in a sufficiently low temperature and low pressure state into superheated steam, the steam passes through the exhaust heat recovery device 10. , it returns to fully superheated steam. The superheated steam enters the accumulator 8 from the four-way switching valve 6, and after becoming completely in a vapor phase in the accumulator 8, returns to the regular side compressor C1. This refrigerant cycle is repeated to provide heating.

FIG. 2 is a plan sectional view of the multi-type compressor of the present invention, and FIG. 3 is a sectional view taken along the line BB in FIG.
It is an AA sectional arrow view of. In FIG. 1, the multi-type compressor has rotors 7 and 9 and oil separators 27 and 23 arranged inside a main case 2 and lid cases 25 and 23. Then, cylinders 40 and 41 are attached to the outer periphery of the rotors 7 and 9.
are arranged and protrude from the rotors 7 and 9, and the cylinders 40 and
Vanes 3 and 5 are configured to come into contact with the inner surface of 41. The rotors 7 and 9 drive the rotation of drive pulleys 11 and 13 via electromagnetic clutches 15 and 17. In addition, the rotating sides of the rotors 7 and 9 are connected to the rear side blocks 29 and 31.
It is closed by front side blocks 19 and 21. The aforementioned cylinders 40, 41, rear side blocks 29, 31, and front side blocks 19, 21 constitute a sealed chamber.

Next, a description will be given with reference to FIG. A suction port 35 is formed in a portion of the lid cases 25 and 23 configured to cover the main case 2, and a suction check valve 45 is formed inside the suction port 35. Then, the refrigerant sucked from the suction port 35 through the suction check valve 45 is compressed into high-temperature, high-pressure saturated steam by the rotors 7 and 9 and the vanes 3 and 5, and is then sent to the oil separators 27 and 23 or the main It is discharged into the case 2. and main case 2
Inside, there is an oil reservoir in the lower part, and the upper part is a high-temperature, high-pressure refrigerant gas chamber. Then, high temperature and high pressure superheated steam is discharged from the discharge port 37. 47 and 48 are lubricating oil suction circuits, and rotors 7 and 48 are lubricating oil suction circuits.
It lubricates the rotating parts of 9.

Next, FIG. 7 is an enlarged sectional view of the reed valve portion of FIG. 4, and FIG. 8 is a perspective view of the liquid sealing projection surface 55 on the back of the vane.
FIG. 9 is also an enlarged sectional view. A mechanism for sucking liquid refrigerant and discharging it as high-temperature, high-pressure superheated steam will be described with reference to FIGS. 4, 7, 8, and 9. Cylinder suction ports 49, 49 are arranged 180 degrees apart in the cylinders 40, 41, and cylinder discharge ports 53, 53 are arranged. The vanes 3 and 5 rotated by the rotors 7 and 9 protrude from the recesses 60 and 61 provided in the cylinders 40 and 41, so the cylinder suction ports 49 and The refrigerant is sucked from 49. In this sucked state, the refrigerant reaches the liquid sealing projection surface 55 and is sealed, and the protruding vanes 3 and 5 are pushed back again. is discharged from the cylinder discharge port 5.
3.53, it reaches the discharge port 37.

The above is the overall configuration of the multi-type compressor. FIG. 5 is a drawing showing a refrigerant circuit of a multi-type compressor of the present invention, which shows the technique of claim 1. In the present invention, in the configuration, as shown in FIG. 5, in the refrigerant circuit of a multi-type compressor provided with a regular side compressor C1 and a starting/stopping side compressor C2, a check valve is installed in the suction line on the side of the starting/stopping side compressor C2. 63, a refrigerant circuit communicating the downstream side of the check valve and the discharge line, and a solenoid valve 64 provided in the refrigerant circuit. That is,
When operating only the regular-use compressor C1 of a multi-type compressor, the discharged gas flows from the start/stop side compressor C2.
A suction check valve 45 has been provided in the suction port 35 to prevent light oil from flowing back into the suction line from the cylinder 41, but it is impossible to make the suction check valve 45 maintain complete airtightness. Therefore, the bearings of rotors 7 and 9 and the rotor 7
- Lubricating oil gradually enters the stopped cylinder 41 of the start/stop side compressor C2 through the gaps between the vanes 3 and 9 and the vanes 3 and 5. When the start/stop side compressor C2 is stopped for a long time, the inside of the cylinder 41 is completely filled with lubricating oil, and then the clutch 1 of the start/stop side compressor C2 is stopped.
When 7 is turned on, compression of liquid oil starts, and an overload is applied to the drive type. This reduces the durability of the multi-type compressor.

In order to solve this problem, a check valve 63 and a solenoid valve 64 are provided. Regular use side compressor C
1 and the start/stop side compressor C2 are operated at the same time, the solenoid valve 64 is closed. When only the regular compressor C1 is in operation, the solenoid valve 64 is opened. As a result, the pressure on the discharge side of the discharge port 37 is applied to the start/stop side compressor C2 via the opened electromagnetic valve 64.
The lubricating oil can be prevented from entering the cylinder 41. In this case, the pressure from the solenoid valve 64 is applied to the suction port 35.
A check valve 63 is provided to prevent this from happening again. When the start/stop side compressor C2 is also operated, the solenoid valve 64 is closed and the refrigerant flows through the check valve 63.
is opened, and the air is sucked into the suction port 39. Further, when the regular use side compressor C1 and the start/stop side compressor C2 are operated simultaneously, the solenoid valve 64 is closed.

FIG. 6 also shows that in a refrigerant circuit of a multi-type compressor provided with a regular use side compressor C1 and a start/stop side compressor C2, a check valve is provided in the discharge line of the compressor, and the discharge port and the FIG. 2 is a circuit diagram showing a configuration in which a refrigerant passage is provided that communicates an intermediate portion of a check valve with a compressor suction line, and a solenoid valve is provided in the intermediate portion of the refrigerant passage. In other words, a multi-type compressor may be operated with only one of the two units in order to control the capacity, but if the start/stop side compressor C2 is also driven during the process, there will be a gap between the suction and discharge lines. , since a pressure difference has already occurred, the start/stop side compressor C2 turns the clutch 17 to O.
The moment it is set to N, it is subjected to an excessive load. It is configured to eliminate this problem.

That is, it is constructed as shown in FIG. 6 in case a pressure difference occurs between the discharge line and the suction line. That is, when only the regular side compressor C1 is in operation and the start/stop side compressor C2 is to be driven next, the solenoid valve 65 is turned on before the clutch 17 is connected to open the short circuit. As a result, the regular use side compressor C1
The generated pressure gas passes through the solenoid valve 65 and flows into the suction port 39 of the start/stop side compressor C2, so that the suction line and the discharge line become equal. After this, the clutch 17 of the start/stop side compressor C2 is turned on. A multi-type compressor equipped with a plurality of reed valves 51, 51 utilizes the pressure difference between discharge and suction to
51 is pressed against the cylinders 40 and 41,
When the solenoid valve 65 is opened to equalize the pressures on the suction side and the discharge side, compression operation does not occur, and a sudden shock occurring in the start/stop side compressor C2 can be prevented.

Next, claim 2 will be explained with reference to FIGS. 8 and 9. In the refrigerant circuit of a multi-type compressor that includes a regular-use compressor C1 and a start/stop side compressor C2, the chattering characteristic of the regular-use compressor C1 is such that even in a state where there is no difference between high and low refrigerant pressures, the vanes are attached to the cylinder wall due only to the centrifugal force of the vanes. The chattering characteristic of the start/stop side compressor C2 is configured such that the vane can follow the cylinder wall surface only after the vane extrusion force is applied due to the refrigerant high-low pressure difference.

[0021] Vane chatter refers to a condition in which, during the compression process, the vanes 3 and 5 are pushed back toward the rotor by the compression pressure, creating a gap between the cylinder and the vanes 3 and 5, and the compression pressure does not increase. . In the case where the regular use side compressor C1 is in operation and the start/stop side compressor C2 is then started to operate in order to improve the capacity, the present invention provides the following:
A situation occurs in which the oil that has entered the cylinder is compressed,
An excessive load is applied to compress the oil, but in order to prevent this from occurring, the liquid seal protrusion 55 on the start/stop side compressor C2 has been improved to prevent chattering from occurring easily. It is something to do.

The multi-type compressor is equipped with check valves 45 and 66 at the suction ports 35 and 39 to prevent the discharged gas from flowing back into the suction line via the start/stop side compressor C2 when only the regular side compressor C1 is operated. However, since it is impossible to maintain the check valve 45 in a completely airtight state, oil gradually enters the cylinder of the start/stop side compressor C2 through the gaps between the rotor shaft, vanes, and rotor. be. When the start/stop side compressor C2 is stopped for a long time, the inside of the cylinder 41 is completely filled with oil, so when the clutch 17 is turned on in this state, oil compression occurs. In order to eliminate this problem, the following configuration was adopted.

Pressure from the gas discharged from the main case 2 is applied to the back surface of the vane via the oil reservoirs in the rear side blocks 29 and 31 and the front side blocks 19 and 21.
The vanes 3 and 5 are made to follow the inner surfaces of the cylinders 40 and 41. Near the final compression process, the rear side block 29
・In the oil pools of 31 and front side blocks 19 and 21, a protruding surface 55 for liquid sealing is provided to seal the back surface of the vanes to prevent chattering by preventing vanes 3 and 5 from being pushed in by compression pressure. is being prevented. In the present invention, as shown in FIG. 9, the liquid seal protrusion surface 55 on the side of the compressor C1 in regular use is made large to prevent chattering, but the liquid seal protrusion surface 55 on the side of the main case 2 is made large. 57 is made small so that the oil can easily escape when the main case 2 starts to be driven when the oil is compressed. This eliminates the excessive load due to oil compression.

[0024]

[Effects of the Invention] Since the present invention is constructed as described above, the following effects can be achieved. In other words, since the structure is configured as in claim 1, by opening the solenoid valve 64, the pressure on the discharge side of the regular side compressor C1 acts on the suction port of the main case 2, so that the oil in the main case 2 flows into the cylinder. Entry is no longer possible, and the start/stop side compressor C2
Even if the engine started driving, the oil compression state no longer occurred.

Next, since the structure is configured as in claim 2, when the starting/stopping side compressor C2 is stopped, the cylinder is filled with oil and the clutch 17 of the starting/stopping side compressor C2 is closed.
Even when the engine is turned on, the liquid seal protrusion surface 57 of the start/stop side compressor C2 is configured to be smaller than the liquid seal protrusion surface 55 of the regular use side compressor C1, so that the oil does not leak in the final compression stroke. This allowed the excess load associated with oil compression to be avoided.

Next, with the configuration as claimed in claim 3, by opening the solenoid valve 65, the discharged gas from the regular side compressor C1 flows into the suction side of the regular side compressor C1 and the start/stop side compressor C2. Since the pressure difference between the suction side and the discharge side is eliminated, and the reed valves 51, 51 no longer close, it is possible to avoid the impact caused by the pressure difference when starting the drive of the start/stop side compressor C2.

[Brief explanation of drawings]

FIG. 1 is a refrigerant circuit diagram of an engine heat pump device in which one engine 1 drives two compressors, a regular-use compressor C1 and a start/stop compressor C2.

2 is a plan sectional view of the multi-type compressor of the present invention, and is a sectional view taken along line BB in FIG. 3. FIG.

FIG. 3 is a side cross-sectional view of the regular-use compressor C1.

FIG. 4 is a cross-sectional view taken along the line AA in FIG. 3;

FIG. 5 is a drawing showing a refrigerant circuit of a multi-type compressor of the present invention, which shows the technique of claim 1.

FIG. 6 is a refrigerant circuit diagram showing the technology of claim 3.

FIG. 7 is a drawing showing the relationship between the vanes 3 and 5 and the liquid sealing protruding surfaces 55 and 57.

FIG. 8 is a perspective view showing a liquid sealing projection surface 55. FIG.

FIG. 9 is a drawing showing the sizes of liquid sealing projection surfaces 55 and 57.

[Explanation of symbols]

C1 Regular use side compressor C2 Start/stop side compressor 1 Engine 2 Main case 3,5 Vane 6 4-way switching valve 35, 39 Suction port 37 Discharge port 51 Reed valve 63, 64 Solenoid valve

Claims (3)

[Claims] Claim 1: In a refrigerant circuit of a multi-type compressor including a regular-use compressor C1 and a starting/stopping compressor C2, a check valve is provided in the suction line on the side of the starting/stopping compressor C2, and a check valve is provided on the downstream side of the check valve. 1. A refrigerant circuit for a multi-type compressor, characterized in that a refrigerant circuit is provided for communicating between the refrigerant circuit and a discharge line, and a solenoid valve is provided in the refrigerant circuit. [Claim 2] In a refrigerant circuit of a multi-type compressor that includes a regular-use compressor C1 and a start/stop side compressor C2, the chattering characteristic of the regular-use compressor C1 is such that even in a state where there is no difference in refrigerant high and low pressure, the cylinder is moved only by the centrifugal force of the vanes. A multi-type compressor characterized in that the vanes can follow the cylinder wall surface, and the chattering characteristic of the start/stop side compressor C2 is such that the vane can follow the cylinder wall surface only when a vane extrusion force is applied due to the difference in high and low refrigerant pressure. refrigerant circuit. 3. In a refrigerant circuit of a multi-type compressor provided with a regular use side compressor C1 and a start/stop side compressor C2, a check valve is provided in the discharge line of the compressor,
A refrigerant circuit for a multi-type compressor, characterized in that a refrigerant passage is provided that connects a discharge port, an intermediate portion of the check valve, and a compressor suction line, and a solenoid valve is provided in the intermediate portion of the refrigerant passage.