US20020023459A1 - Freezing apparatus - Google Patents
Freezing apparatus Download PDFInfo
- Publication number
- US20020023459A1 US20020023459A1 US09/899,414 US89941401A US2002023459A1 US 20020023459 A1 US20020023459 A1 US 20020023459A1 US 89941401 A US89941401 A US 89941401A US 2002023459 A1 US2002023459 A1 US 2002023459A1
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- United States
- Prior art keywords
- compressor
- oil
- pipe
- refrigerant
- high pressure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000008014 freezing Effects 0.000 title 1
- 238000007710 freezing Methods 0.000 title 1
- 239000003507 refrigerant Substances 0.000 claims abstract description 127
- 230000006835 compression Effects 0.000 claims description 19
- 238000007906 compression Methods 0.000 claims description 19
- 230000001174 ascending effect Effects 0.000 claims description 4
- 239000000314 lubricant Substances 0.000 abstract description 3
- 238000004378 air conditioning Methods 0.000 description 2
- 238000005461 lubrication Methods 0.000 description 2
- 238000011144 upstream manufacturing Methods 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
Images
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
- F04C23/008—Hermetic pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B43/00—Arrangements for separating or purifying gases or liquids; Arrangements for vaporising the residuum of liquid refrigerant, e.g. by heat
- F25B43/02—Arrangements for separating or purifying gases or liquids; Arrangements for vaporising the residuum of liquid refrigerant, e.g. by heat for separating lubricants from the refrigerant
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
- F04C23/001—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids of similar working principle
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
- F04C29/02—Lubrication; Lubricant separation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
- F04C29/02—Lubrication; Lubricant separation
- F04C29/026—Lubricant separation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B31/00—Compressor arrangements
- F25B31/002—Lubrication
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
- F04C18/02—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents
- F04C18/0207—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form
- F04C18/0215—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form where only one member is moving
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
- F04C29/02—Lubrication; Lubricant separation
- F04C29/028—Means for improving or restricting lubricant flow
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
- F25B2400/07—Details of compressors or related parts
- F25B2400/075—Details of compressors or related parts with parallel compressors
Definitions
- the present invention concerns a freezer unit (including air conditioner) composed by providing a plurality of compressors for compressing refrigerant in parallel.
- the lubricant oil (called simply oil, hereinafter) that the compressor holds is discharged from the compressor with compressed refrigerant, lowering the oil level in the compressor and the lubrication becomes insufficient; therefore, an oil separator is installed in the refrigerant discharge pipe, in a way to return oil separated from refrigerant by this oil separator.
- a freezer unit comprising a plurality of compressors of a vessel structure having a low pressure portion and a high pressure portion divided through a discharge port of a compression pump and internal high pressure compressors are installed in parallel
- an oil sensor for detecting the oil level surface is installed in respective compressors, and the oil quantity balance of respective compressors is maintained by controlling the oil return quantity from the oil separator based on the state of the oil level surface.
- the present invention intends to solve the problems of the prior art mentioned above, by providing:
- a freezer unit of a first composition comprising a single refrigerant circuit where a plurality of internal high pressure type compressors are installed in parallel, wherein an oil separator is installed in a discharged refrigerant junction pipe where meet and flow refrigerant discharged from respective compressors, a first kind oil return pipe leading to a refrigerant suction pipe of a first compressor from this oil separator is installed, and a second kind oil return pipe leading to a refrigerant suction pipe of a second compressor from the regular oil level height of the first compressor,
- a freezer unit of a second composition comprising a refrigerant circuit where a plurality of internal high pressure type compressors is installed in parallel, wherein an oil separator is installed in a discharged refrigerant junction pipe where meet and flow refrigerant discharged from respective compressors, a first kind oil return pipe provided with an on-off valve in the pipe leading to a refrigerant suction pipe of each compressors from this oil separator is installed, and a second kind oil return pipe leading to a refrigerant suction pipe of a second compressor from the regular oil level height of the first compressor is installed,
- a freezer unit of a third composition wherein the first compressor is a variable compression capacity type compressor in the freezer unit of said first or second composition
- a freezer unit of a fourth composition comprising a refrigerant circuit where a plurality of compressors of a vessel structure having a low pressure portion and a high pressure portion divided through a discharge port of a compression pump are installed in parallel, wherein an oil balance pipe provided with a pressure reduction means leading from the high pressure portion of a compressor to a refrigerant suction pipe of another compressor is installed,
- a freezer unit of a fifth composition comprising a refrigerant circuit where a first compressor of a vessel structure having a low pressure portion and a high pressure portion divided through a discharge port of a compression pump and a second compressor of a high pressure vessel structure are installed in parallel, wherein an oil balance pipe provided with a pressure reduction means leading to a refrigerant suction pipe of the second compressor from the high pressure portion of the second compressor, and an oil balance pipe provided with a pressure reduction means leading to a refrigerant suction pipe of the first compressor from the vicinity of the regular oil level surface of the second compressor is installed,
- a freezer unit of a sixth composition wherein one end of the oil balance pipe is connected to the ascending slope portion of a branched refrigerant suction pipe in the freezer unit of said fourth or fifth composition, and
- a freezer unit of a seventh composition 6 wherein the refrigerant suction pipe is connected horizontally to the compressor, and one end of the oil balance pipe is connected to a position where a central angle ⁇ on an arc between the refrigerant suction pipe and the oil balance pipe becomes equal or inferior to 45 degrees, at the underside of this refrigerant suction pipe connection part in the freezer unit of one of claim 4 to 6, as concrete means to solve problems of the aforementioned prior art.
- FIG. 1 is an illustration showing a first embodiment of the invention
- FIG. 2 is an illustration showing a second embodiment of the invention
- FIG. 3 is an illustration showing a third embodiment of the invention.
- FIG. 4 is an illustration showing essential parts of the third embodiment
- FIG. 5 is an illustration showing a fourth embodiment of the invention.
- 1 and 2 indicate internal high pressure type compressors composing a freezer unit with not shown condenser, evaporator or others, and installed in parallel in a single refrigerant circuit.
- one compressor 1 is connected to one refrigerant suction pipe 4 branching from a refrigerant suction pipe 3
- the other compressor 2 is connected to the other refrigerant suction pipe 5 branching from a refrigerant suction pipe 3
- a refrigerant discharge pipe 6 , 7 and a discharged refrigerant junction pipe 8 are installed so that refrigerant compressed by the one compressor 1 is discharged into one refrigerant discharge pipe 6 while refrigerant compressed by the other compressor 2 is discharged into the other refrigerant discharge pipe 7 , meet each other, and supply not shown condenser, evaporator or others by circulation.
- an oil separator 9 provided with conventionally well-known functions per se is installed in the discharged refrigerant junction pipe 8 , a fist kind oil return pipe 10 from this oil separator 9 to the refrigerant suction pipe 4 to which one of compressors 1 , 2 , for example, compressor 1 provided with a variable refrigerant compressing capability is installed, and a capillary tube 11 as pressure reducing means is installed in the middle of this fist kind oil return pipe 10 .
- a second kind oil return pipe 12 is connected to the level of the regular oil surface of the compressor 1 , the other end thereof is connected to the refrigerant suction pipe 5 connected to the compressor 2 of non variable refrigerant compression capability, and a capillary tube 13 as pressure reducing means is installed in the middle of this second kind oil return pipe 12 .
- both compressors 1 , 2 are operated, and for a save operation, with low air-conditioning load, only compressor 1 provided with variable refrigerant compressing capability is operated.
- oil discharged to the refrigerant discharge pipe 6 , 7 with refrigerant from the compressor 1 , 2 is separated from the refrigerant by the oil separator 9 .
- oil stored in the oil separator 9 returns first to the compressor 1 through the downstream portion of the first oil return pipe 10 and the refrigerant suction pipe 4 and, further, oil in the compressor 1 positioned higher than the connection portion with the second kind oil return pipe 12 returns to the compressor 2 through the downstream portion of the second oil return pipe 12 and the refrigerant suction pipe 5 .
- fist kind oil return pipe 10 A is installed so as to allow to communicate between the oil separator 9 , and the upstream side of the capillary tube 13 of the second kind oil return pipe 12 , and to return oil stored in the oil separator 9 without passing through the compressor 1 .
- the fist kind oil return pipe 10 is provided with an on-off valve 14 and the fist kind oil return pipe l 0 A with an on-off valve 15 .
- the on-off valve 14 is opened and the on-off valve 15 is closed to operate both compressors 1 , 2 , and for the save operation with low air-conditioning load, only one side of the compressor 1 or compressor 2 is operated. At this moment, the on-off valve 14 is opened and the on-off valve 15 is closed for operating only the compressor 1 , while the on-off valve 15 is opened and the on-off valve 14 is closed when only the compressor 2 is operated.
- the compressor 1 , 2 in this embodiment is a low pressure scroll type compressor having a vessel structure, dividing the low pressure portion L and the high pressure portion H through a discharge section P 1 of a compression pump P. Further, oil 25 is stored at the bottom of the low pressure portion L for lubrication.
- One refrigerant suction pipe 4 branching from a refrigerant suction pipe 3 is connected to the low pressure portion L of the compressor 1
- the other refrigerant suction pipe 5 branching from a refrigerant suction pipe 3 is connected to the low pressure portion L of the compressor 2 .
- a refrigerant discharge pipe 6 is connected to the high pressure portion H of the compressor 1
- a refrigerant discharge pipe 7 is connected to the high pressure portion H of the compressor 2
- a discharged refrigerant junction pipe 8 is installed so that high pressure refrigerant discharged into the refrigerant discharge pipe 6 , 7 meet each other, and supply not shown condenser, evaporator or others by circulation.
- an accumulator 17 is installed in the refrigerant suction pipe 3 , and respective refrigerant discharge pipe 6 , 7 is provided with a check valve.
- an oil balance pipe 18 is installed from the high pressure portion H of the compressor 1 to the refrigerant suction pipe 5 , and a capillary tube 19 as pressure reducing means is installed in the middle of this oil balance pipe 18 .
- an oil balance pipe 20 is installed from the high pressure portion H of the compressor 2 to the refrigerant suction pipe 4 , and a capillary tube 21 as pressure reducing means is installed in the middle of this oil balance pipe 20 .
- the refrigerant discharge pipe 6 , 7 is connected horizontally to the compressor 1 , 2 , as shown in FIG. 4, and one end of the oil balance pipe 18 , 20 is connected thereunder. At this moment, the refrigerant discharge pipe 6 and the oil balance pipe 18 , or the refrigerant discharge pipe 7 and the oil balance pipe 20 are both connected at a position where the central angle ⁇ becomes equal or inferior to 45 degrees.
- the other end of the oil balance pipe 18 , 20 is connected to the ascending slope portion of the refrigerant suction pipe 4 , 5 branched from the refrigerant suction pipe 3 .
- High pressure refrigerant compressed by the compression pump P and supplied to the high pressure portion H from the discharge section P 1 is discharged into the refrigerant discharge pipe 6 , 7 , therefore, it flows much from the discharge portion P 1 to the connection part of the refrigerant discharge pipe 6 , 7 , and oil 25 separated from the refrigerant accumulates more at the bottom of this passage.
- oil 25 accumulated in the high pressure portion H of the compressor 1 is sucked in the low pressure portion L of the compressor 2 with refrigerant gas through the oil balance pipe 18 and the refrigerant suction pipe 5
- oil 25 accumulated in the high pressure portion H of the compressor 2 is sucked in the low pressure portion L of the compressor 1 with refrigerant gas through the oil balance pipe 20 and the refrigerant suction pipe 4 , 5 , and added to oil 25 accumulated at the respective bottom.
- the freezer unit shown in this FIG. 5 is a freezer unit where a compressor 1 of low pressure scroll type of the same structure as the compressor 1 , 2 shown in said FIG. 3, and a compressor 2 of internal high pressure type of the same structure as the compressor 1 , 2 shown in said FIG. 1, FIG. 2 are arranged in parallel to the refrigerant pipe.
- the high pressure portion H of the compressor 1 and the refrigerant suction pipe 5 are connected by an oil balance pipe 18 provided with a capillary tube 19 , and the vicinity of the regular oil level surface of the compressor 2 and the refrigerant suction pipe 4 are connected by an oil balance pipe 22 provided with a capillary tube 23 .
- oil 25 that has lubricated the sliding parts of the compression pump P is discharged into the high pressure portion H with compressed refrigerant, and accumulated at the bottom of this high pressure portion H. Then, oil 25 accumulated in the high pressure portion H of the compressor 1 is sucked in the low pressure portion L of the compressor 2 with refrigerant gas through the oil balance pipe 18 and the refrigerant suction pipe 5 , and a part of oil 25 mixed into the compression gas is discharged into the refrigerant discharge pipe 7 with refrigerant gas, but oil 25 separated in the high pressure portion H accumulates at the bottom thereof, and is supplied to respective sliding parts.
- freezer unit of the first embodiment shown in FIG. 1 freezer unit of the second embodiment shown in FIG. 2 and freezer unit of the third embodiment shown in FIG. 3, the freezer unit can be composed by installing three or more compressors in parallel.
- an on-off valve 16 may be disposed in the second kind oil return pipe 12 and the on-off valve 14 is opened and the on-off valve 15 , 16 are closed for operating only the compressor 1 , the on-off valve 15 is opened and the on-off valve 14 , 16 are closed when only the compressor 2 is operated and the on-off valve 14 , 16 are opened and the on-off valve 15 is closed to operate both compressors.
- an oil balance pipe provided with a pressure reducing means in the pipe leading to the refrigerant suction pipe of the second compressor from the high pressure portion of the first compressor is installed
- an oil balance pipe provided with a pressure reducing means in the pipe leading to the refrigerant suction pipe of the third compressor from the high pressure portion of the second compressor is installed
- an oil balance pipe provided with a pressure reducing means in the pipe leading to the refrigerant suction pipe of the n th compressor from the high pressure portion of the n- 1 th compressor is installed similarly and sequentially
- an oil balance pipe provided with a pressure reducing means in the pipe leading to the refrigerant suction pipe of the first compressor from the high pressure portion of the n th compressor is installed.
- an oil separation plate may be disposed in the high pressure portion, H and the refrigerant suction pipe and the oil balance pipe may be disposed at a position where the central angle ⁇ becomes equal or inferior to 45 degrees.
- the compressor operation time can be balanced, because the compressor to be operated for a partial load can be selected freely.
- oil can be received or delivered between compressors in operation independently of the stopped compressor, because one end of the oil balance pipe is connected to the upstream section installed on the ascending slope portion of the refrigerant suction pipe.
- oil accumulated near the refrigerant discharge pipe connection part is supplied effectively to the other compressor through the oil balance pipe, as the refrigerant suction pipe and the oil balance pipe approach so that the central angle ⁇ becomes equal or inferior to 45 degrees, and, the oil balance pipe is connected to the underside of the refrigerant discharge pipe.
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- Engineering & Computer Science (AREA)
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- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
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Abstract
Description
- 1. Field of the Invention
- The present invention concerns a freezer unit (including air conditioner) composed by providing a plurality of compressors for compressing refrigerant in parallel.
- 2. Detailed Description of the Prior Art
- In general, the lubricant oil (called simply oil, hereinafter) that the compressor holds is discharged from the compressor with compressed refrigerant, lowering the oil level in the compressor and the lubrication becomes insufficient; therefore, an oil separator is installed in the refrigerant discharge pipe, in a way to return oil separated from refrigerant by this oil separator.
- On the other hand, in a freezer unit connecting in parallel a plurality of compressors provided with a oil reservoir section in the low pressure portion, oil quantity balance is maintained by communication respective oil reservoir sections through an oil balance pipe.
- However, in case of freezer unit wherein oil quantity balance is maintained by communication respective oil reservoir sections through an oil balance pipe, when at least one of compressors is a capacity controllable compressor, or when a plurality of compressors of different compression capacity are connected in parallel for enlarging the scale, oil increases in the high output compressor, oil lacks in the low output compressor, abrasion progresses at the sliding parts of oil lacking compressors, and the apparatus life reduces or other problems occur, because the pressure difference is generated in the compression vessel, oil is sucked by the high output compressor, or for other reasons.
- It is necessary to connect an oil balance pipe having a large diameter to a compressor of high output, in order to solve the imbalance of oil quantity; however, the oil balance pipe becomes complicated, and increases the cost, because an effort is applied to the oil balance pipe when the compressor is started.
- Also, in a freezer unit comprising a plurality of compressors of a vessel structure having a low pressure portion and a high pressure portion divided through a discharge port of a compression pump and internal high pressure compressors are installed in parallel, an oil sensor for detecting the oil level surface is installed in respective compressors, and the oil quantity balance of respective compressors is maintained by controlling the oil return quantity from the oil separator based on the state of the oil level surface.
- However, the oil sensor is complicated in structure and expensive. In, addition, the oil return control circuit also become complicated and expensive.
- [Means for Solving the Problems]
- Therefore, it is necessary to avoid lack of oil in some compressors by a simple composition without cost increase, even if refrigerant compression capacity differs or the passage resistance of the refrigerant discharge pipe differs from one compressor to the other, and it has been the problem to be resolved.
- The present invention intends to solve the problems of the prior art mentioned above, by providing:
- a freezer unit of a first composition comprising a single refrigerant circuit where a plurality of internal high pressure type compressors are installed in parallel, wherein an oil separator is installed in a discharged refrigerant junction pipe where meet and flow refrigerant discharged from respective compressors, a first kind oil return pipe leading to a refrigerant suction pipe of a first compressor from this oil separator is installed, and a second kind oil return pipe leading to a refrigerant suction pipe of a second compressor from the regular oil level height of the first compressor,
- a freezer unit of a second composition comprising a refrigerant circuit where a plurality of internal high pressure type compressors is installed in parallel, wherein an oil separator is installed in a discharged refrigerant junction pipe where meet and flow refrigerant discharged from respective compressors, a first kind oil return pipe provided with an on-off valve in the pipe leading to a refrigerant suction pipe of each compressors from this oil separator is installed, and a second kind oil return pipe leading to a refrigerant suction pipe of a second compressor from the regular oil level height of the first compressor is installed,
- a freezer unit of a third composition, wherein the first compressor is a variable compression capacity type compressor in the freezer unit of said first or second composition,
- a freezer unit of a fourth composition comprising a refrigerant circuit where a plurality of compressors of a vessel structure having a low pressure portion and a high pressure portion divided through a discharge port of a compression pump are installed in parallel, wherein an oil balance pipe provided with a pressure reduction means leading from the high pressure portion of a compressor to a refrigerant suction pipe of another compressor is installed,
- a freezer unit of a fifth composition comprising a refrigerant circuit where a first compressor of a vessel structure having a low pressure portion and a high pressure portion divided through a discharge port of a compression pump and a second compressor of a high pressure vessel structure are installed in parallel, wherein an oil balance pipe provided with a pressure reduction means leading to a refrigerant suction pipe of the second compressor from the high pressure portion of the second compressor, and an oil balance pipe provided with a pressure reduction means leading to a refrigerant suction pipe of the first compressor from the vicinity of the regular oil level surface of the second compressor is installed,
- a freezer unit of a sixth composition, wherein one end of the oil balance pipe is connected to the ascending slope portion of a branched refrigerant suction pipe in the freezer unit of said fourth or fifth composition, and
- a freezer unit of a
seventh composition 6, wherein the refrigerant suction pipe is connected horizontally to the compressor, and one end of the oil balance pipe is connected to a position where a central angle θ on an arc between the refrigerant suction pipe and the oil balance pipe becomes equal or inferior to 45 degrees, at the underside of this refrigerant suction pipe connection part in the freezer unit of one ofclaim 4 to 6, as concrete means to solve problems of the aforementioned prior art. - FIG. 1 is an illustration showing a first embodiment of the invention;
- FIG. 2 is an illustration showing a second embodiment of the invention;
- FIG. 3 is an illustration showing a third embodiment of the invention;
- FIG. 4 is an illustration showing essential parts of the third embodiment;
- FIG. 5 is an illustration showing a fourth embodiment of the invention.
- First Embodiment
- Now, a first embodiment of the present invention will be described in detail, based on FIG. 1.
- In the drawing,1 and 2 indicate internal high pressure type compressors composing a freezer unit with not shown condenser, evaporator or others, and installed in parallel in a single refrigerant circuit.
- In short, one
compressor 1 is connected to onerefrigerant suction pipe 4 branching from arefrigerant suction pipe 3, and theother compressor 2 is connected to the otherrefrigerant suction pipe 5 branching from arefrigerant suction pipe 3. In addition, arefrigerant discharge pipe compressor 1 is discharged into onerefrigerant discharge pipe 6 while refrigerant compressed by theother compressor 2 is discharged into the otherrefrigerant discharge pipe 7, meet each other, and supply not shown condenser, evaporator or others by circulation. - Then, an oil separator9 provided with conventionally well-known functions per se is installed in the discharged refrigerant junction pipe 8, a fist kind
oil return pipe 10 from this oil separator 9 to therefrigerant suction pipe 4 to which one ofcompressors compressor 1 provided with a variable refrigerant compressing capability is installed, and a capillary tube 11 as pressure reducing means is installed in the middle of this fist kindoil return pipe 10. - In addition, one end of a second kind
oil return pipe 12 is connected to the level of the regular oil surface of thecompressor 1, the other end thereof is connected to therefrigerant suction pipe 5 connected to thecompressor 2 of non variable refrigerant compression capability, and acapillary tube 13 as pressure reducing means is installed in the middle of this second kindoil return pipe 12. - For a full power operation of the freezer unit of the aforementioned composition, both
compressors compressor 1 provided with variable refrigerant compressing capability is operated. - In the freezer unit of the invention, oil discharged to the
refrigerant discharge pipe compressor compressor 1 through the downstream portion of the firstoil return pipe 10 and therefrigerant suction pipe 4 and, further, oil in thecompressor 1 positioned higher than the connection portion with the second kindoil return pipe 12 returns to thecompressor 2 through the downstream portion of the secondoil return pipe 12 and therefrigerant suction pipe 5. - Moreover, as the
compressor 1 side connection area of the second kindoil return pipe 12 is connected to the oil regular height, oil does not return to thecompressor 2 so much as provoking lack of oil in thecompressor 1, and oil is not stored excessively in thecompressor 1 provoking lack of oil in thecompressor 2. - Second Embodiment
- Now, a second embodiment of the invention will be described in detail based on FIG. 2.
- In the freezer unit shown in FIG. 2, parts having the same function as the freezer unit shown in said FIG. 1 are indicated by the same symbols so as to facilitate the comprehension.
- In the freezer unit shown in this FIG. 2, still another fist kind
oil return pipe 10A is installed so as to allow to communicate between the oil separator 9, and the upstream side of thecapillary tube 13 of the second kindoil return pipe 12, and to return oil stored in the oil separator 9 without passing through thecompressor 1. In addition, the fist kindoil return pipe 10 is provided with an on-off valve 14 and the fist kind oil return pipe l0A with an on-off valve 15. - For a full power operation of the freezer unit of the aforementioned composition, the on-off valve14 is opened and the on-off valve 15 is closed to operate both
compressors compressor 1 orcompressor 2 is operated. At this moment, the on-off valve 14 is opened and the on-off valve 15 is closed for operating only thecompressor 1, while the on-off valve 15 is opened and the on-off valve 14 is closed when only thecompressor 2 is operated. - Third Embodiment
- Now, a third embodiment of the invention will be described in detail based on FIG. 3 and FIG. 4.
- In these illustrations showing the third embodiment also, parts having the same function as the freezer unit shown in said drawings are indicated by the same symbols so as to facilitate the comprehension.
- The
compressor oil 25 is stored at the bottom of the low pressure portion L for lubrication. - One
refrigerant suction pipe 4 branching from arefrigerant suction pipe 3 is connected to the low pressure portion L of thecompressor 1, and the otherrefrigerant suction pipe 5 branching from arefrigerant suction pipe 3 is connected to the low pressure portion L of thecompressor 2. - In addition, a
refrigerant discharge pipe 6 is connected to the high pressure portion H of thecompressor 1, and arefrigerant discharge pipe 7 is connected to the high pressure portion H of thecompressor 2, and a discharged refrigerant junction pipe 8 is installed so that high pressure refrigerant discharged into therefrigerant discharge pipe accumulator 17 is installed in therefrigerant suction pipe 3, and respectiverefrigerant discharge pipe - Further, an
oil balance pipe 18 is installed from the high pressure portion H of thecompressor 1 to therefrigerant suction pipe 5, and acapillary tube 19 as pressure reducing means is installed in the middle of thisoil balance pipe 18. In addition, anoil balance pipe 20 is installed from the high pressure portion H of thecompressor 2 to therefrigerant suction pipe 4, and acapillary tube 21 as pressure reducing means is installed in the middle of thisoil balance pipe 20. - Here, the
refrigerant discharge pipe compressor oil balance pipe refrigerant discharge pipe 6 and theoil balance pipe 18, or therefrigerant discharge pipe 7 and theoil balance pipe 20 are both connected at a position where the central angle θ becomes equal or inferior to 45 degrees. - The other end of the
oil balance pipe refrigerant suction pipe refrigerant suction pipe 3. - In the freezer unit of the aforementioned composition, in both of
compressors oil 25 that has lubricated the sliding parts of the compression pump P is discharged into the high pressure portion H with compressed refrigerant, and if there is some space in this high pressure portion H,oil 25 is separated from the refrigerant therein, and accumulates at the bottom of the high pressure portion H. - High pressure refrigerant compressed by the compression pump P and supplied to the high pressure portion H from the discharge section P1 is discharged into the
refrigerant discharge pipe refrigerant discharge pipe oil 25 separated from the refrigerant accumulates more at the bottom of this passage. - Then, and one end of the
oil balance pipe oil 25 accumulated in the high pressure portion H of thecompressor 1 is sucked in the low pressure portion L of thecompressor 2 with refrigerant gas through theoil balance pipe 18 and therefrigerant suction pipe 5,oil 25 accumulated in the high pressure portion H of thecompressor 2 is sucked in the low pressure portion L of thecompressor 1 with refrigerant gas through theoil balance pipe 20 and therefrigerant suction pipe oil 25 accumulated at the respective bottom. - At this moment, only
oil 25 that has lubricated the sliding parts of respective compression pump P and is discharged in the high pressure portion H thereof is supplied from thecompressor 1 to thecompressor 2, and from thecompressor 2 to thecompressor 1, andoil 25 accumulated in the low pressure portion L is not taken out; therefore, even when the refrigerant compression capability is different for thecompressors oil 25 is prevented from being accumulated excessively in any one ofcompressors - When one compressor, for instance the
compressor 1 is in operation, and theother compressor 2 is stopped, as refrigerant gas does not flow to thecompressor 2 through therefrigerant suction pipe 5,oil 25 that has lubricated the sliding parts of the compression pump P and is discharged in the high pressure portion H of thecompressor 1, and accumulated in the bottom thereof is sucked into thecompressor 1 with refrigerant gas through theoil balance pipe 18, a part of therefrigerant suction pipe 5 and therefrigerant suction pipe 4. Therefore, thecompressor 1 is prevented from being short of oil. - Moreover, as the
refrigerant suction pipe 6 and the oil balance pipe, and therefrigerant suction pipe 7 and theoil balance pipe 20 are mounted on thecompressor oil 25 separated in the high pressure portion H of thecompressor 1 is supplied effectively to the low pressure portion L of thecompressor 2 andoil 25 separated in the high pressure portion H of thecompressor 2 is supplied effectively to the low pressure portion L of thecompressor 1, respectively. - Fourth Embodiment
- Now, a fourth embodiment of the invention will be described in detail based on FIG. 5.
- In these illustrations showing the fourth embodiment also, parts having the same function as the freezer unit shown in said drawings are indicated by the same symbols so as to facilitate the comprehension.
- The freezer unit shown in this FIG. 5 is a freezer unit where a
compressor 1 of low pressure scroll type of the same structure as thecompressor compressor 2 of internal high pressure type of the same structure as thecompressor - And, in this freezer unit, the high pressure portion H of the
compressor 1 and therefrigerant suction pipe 5 are connected by anoil balance pipe 18 provided with acapillary tube 19, and the vicinity of the regular oil level surface of thecompressor 2 and therefrigerant suction pipe 4 are connected by anoil balance pipe 22 provided with acapillary tube 23. - In the freezer unit of the aforementioned composition also,
oil 25 that has lubricated the sliding parts of the compression pump P is discharged into the high pressure portion H with compressed refrigerant, and accumulated at the bottom of this high pressure portion H. Then,oil 25 accumulated in the high pressure portion H of thecompressor 1 is sucked in the low pressure portion L of thecompressor 2 with refrigerant gas through theoil balance pipe 18 and therefrigerant suction pipe 5, and a part ofoil 25 mixed into the compression gas is discharged into therefrigerant discharge pipe 7 with refrigerant gas, butoil 25 separated in the high pressure portion H accumulates at the bottom thereof, and is supplied to respective sliding parts. - On the other hand,
oil 25 accumulated in the high pressure portion H of thecompressor 2 is sucked in the low pressure portion L of thecompressor 1 with refrigerant gas through theoil balance pipe 20 and therefrigerant suction pipe 4 andoil 25 accumulated at the bottom is supplied to respective sliding parts. - In the freezer unit of the structure shown in FIG. 5, as the high pressure portion H of the
compressor 1 of low pressure scroll type is connected through theoil balance pipe 18, onlyoil 25 separated from the refrigerant is supplied from thecompressor 2 to thecompressor 1, and a quantity ofoil 25 accumulated in the low pressure portion L is not sucked even if the capacity of thecompressor 2 is large, and therefore, thecompressors 1 is prevented from being short ofoil 25. - Similarly, for the
oil 25 accumulated in the high pressure portion H of thecompressor 2,oil 25 at the position lower than the regular oil level surface is not sucked by thecompressor 1 through theoil balance pipe 22, because theoil balance pipe 22 is connected to the vicinity of the regular oil level surface; therefore, thecompressors 2 is also prevented from being short ofoil 25. - The invention is not limited to the embodiments shown and described herein; accordingly, various modifications may be made without departing from the spirit or scope as defined by the appended claims.
- For instance, in any of freezer unit of the first embodiment shown in FIG. 1, freezer unit of the second embodiment shown in FIG. 2 and freezer unit of the third embodiment shown in FIG. 3, the freezer unit can be composed by installing three or more compressors in parallel.
- In short, in the freezer unit of the first embodiment shown in FIG. 1, when n (n>=3) compressors in total are installed, a second kind oil return pipe is installed further up to the second kind
oil return pipe 12 leading to the n th compressor from the n-1 th compressor. - Also, when n (n>=3) compressors in total are installed in the freezer unit of the second embodiment shown in FIG. 2, a fist kind oil return pipe providing with an on-off valve leading to the refrigerant suction pipe of all compressors from the oil separator and, at the same time, a second kind oil return pipe is installed up to the second kind oil return pipe leading to the n th compressor from the n-1 th compressor.
- In addition, an on-off
valve 16 may be disposed in the second kindoil return pipe 12 and the on-off valve 14 is opened and the on-offvalve 15, 16 are closed for operating only thecompressor 1, the on-off valve 15 is opened and the on-offvalve 14, 16 are closed when only thecompressor 2 is operated and the on-offvalve 14, 16 are opened and the on-off valve 15 is closed to operate both compressors. - Moreover, when n (n≧3) compressors in total are installed in the freezer unit of the third embodiment shown in FIG. 3, an oil balance pipe provided with a pressure reducing means in the pipe leading to the refrigerant suction pipe of the second compressor from the high pressure portion of the first compressor is installed, an oil balance pipe provided with a pressure reducing means in the pipe leading to the refrigerant suction pipe of the third compressor from the high pressure portion of the second compressor is installed, an oil balance pipe provided with a pressure reducing means in the pipe leading to the refrigerant suction pipe of the n th compressor from the high pressure portion of the n-1 th compressor is installed similarly and sequentially, and further, an oil balance pipe provided with a pressure reducing means in the pipe leading to the refrigerant suction pipe of the first compressor from the high pressure portion of the n th compressor is installed.
- In addition, in the
compressors - It is also possible to combine the piping composition shown in FIG. 3, and the piping composition shown in FIG. 5.
- As abovedescribed, since any of a plurality of compressors installed in series according to the present invention do not cause lack of oil, there are not cases where particular compressor falls into lack of lubricant and a sliding part wears to make the lifetime of an unit short.
- Especially, according to the third invention, the compressor operation time can be balanced, because the compressor to be operated for a partial load can be selected freely.
- In addition, according to the sixth invention, oil can be received or delivered between compressors in operation independently of the stopped compressor, because one end of the oil balance pipe is connected to the upstream section installed on the ascending slope portion of the refrigerant suction pipe.
- Further, according to the seventh invention, oil accumulated near the refrigerant discharge pipe connection part is supplied effectively to the other compressor through the oil balance pipe, as the refrigerant suction pipe and the oil balance pipe approach so that the central angle θ becomes equal or inferior to 45 degrees, and, the oil balance pipe is connected to the underside of the refrigerant discharge pipe.
Claims (7)
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2000-207164 | 2000-07-07 | ||
JP2000207164A JP2002022294A (en) | 2000-07-07 | 2000-07-07 | Refrigeration device |
JP2000207158A JP2002022293A (en) | 2000-07-07 | 2000-07-07 | Refrigeration device |
JP2000-207158 | 2000-07-07 |
Publications (2)
Publication Number | Publication Date |
---|---|
US20020023459A1 true US20020023459A1 (en) | 2002-02-28 |
US6446462B1 US6446462B1 (en) | 2002-09-10 |
Family
ID=26595629
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/899,414 Expired - Fee Related US6446462B1 (en) | 2000-07-07 | 2001-07-05 | Freezing apparatus |
Country Status (6)
Country | Link |
---|---|
US (1) | US6446462B1 (en) |
EP (2) | EP1574794B1 (en) |
KR (1) | KR100807498B1 (en) |
CN (2) | CN1187559C (en) |
DE (1) | DE60113601T2 (en) |
TW (1) | TWI237682B (en) |
Cited By (5)
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US20120006041A1 (en) * | 2009-03-31 | 2012-01-12 | Takashi Ikeda | Refrigerating device |
US20120011872A1 (en) * | 2009-02-27 | 2012-01-19 | Danfoss Commercial Compressors | Device for separating lubricant from a lubricant-refrigerating gas mixture discharged from at least one refrigerant compressor |
US20120023978A1 (en) * | 2010-07-28 | 2012-02-02 | Chae Sunam | Refrigerator and driving method thereof |
CN102865213A (en) * | 2011-07-08 | 2013-01-09 | 珠海格力电器股份有限公司 | Multi-compressor system and oil balancing method and device thereof |
US11713760B2 (en) * | 2017-12-28 | 2023-08-01 | Emerson Climate Technologies (Suzhou) Co., Ltd. | Intake pipe used for compressor system and compressor system |
Families Citing this family (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN100344915C (en) * | 2003-02-27 | 2007-10-24 | 东芝开利株式会社 | Refrigeration cycle apparatus |
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JP2018109451A (en) * | 2016-12-28 | 2018-07-12 | 三菱重工サーマルシステムズ株式会社 | Refrigerant circuit system and oil equalization control method |
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CN110486965B (en) * | 2019-07-17 | 2022-06-14 | 雅凯热能技术(江苏)有限公司 | Refrigeration system based on oil circuit balance of parallel compressors and oil circuit balance method thereof |
CN112577211B (en) * | 2019-09-30 | 2021-12-14 | 约克(无锡)空调冷冻设备有限公司 | Load balancing method for two compressors |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3785169A (en) * | 1972-06-19 | 1974-01-15 | Westinghouse Electric Corp | Multiple compressor refrigeration system |
JPS55107093A (en) * | 1979-02-13 | 1980-08-16 | Hitachi Ltd | Enclosed type scroll compressor |
JP2865707B2 (en) * | 1989-06-14 | 1999-03-08 | 株式会社日立製作所 | Refrigeration equipment |
BR8905970A (en) * | 1989-11-16 | 1991-05-21 | Narcizo Osorio Basseggio | MISCIBLE FLUID COMPRESSION SYSTEM AND PROCESS |
US5236311A (en) * | 1992-01-09 | 1993-08-17 | Tecumseh Products Company | Compressor device for controlling oil level in two-stage high dome compressor |
US5327997A (en) * | 1993-01-22 | 1994-07-12 | Temprite, Inc. | Lubrication management system |
AUPM630094A0 (en) * | 1994-06-17 | 1994-07-14 | Refrigerant Monitoring Systems Pty Ltd | Oil level control device |
AU689273B2 (en) * | 1994-06-29 | 1998-03-26 | Daikin Industries, Ltd. | Refrigerator |
US5586450A (en) * | 1995-09-25 | 1996-12-24 | Carrier Corporation | Plural compressor oil level control |
US6017205A (en) * | 1996-08-02 | 2000-01-25 | Copeland Corporation | Scroll compressor |
-
2001
- 2001-04-17 TW TW090109102A patent/TWI237682B/en not_active IP Right Cessation
- 2001-05-28 KR KR1020010029305A patent/KR100807498B1/en not_active IP Right Cessation
- 2001-06-15 CN CNB011210346A patent/CN1187559C/en not_active Expired - Fee Related
- 2001-06-15 CN CNB2003101204830A patent/CN1260533C/en not_active Expired - Fee Related
- 2001-07-05 US US09/899,414 patent/US6446462B1/en not_active Expired - Fee Related
- 2001-07-06 DE DE60113601T patent/DE60113601T2/en not_active Expired - Fee Related
- 2001-07-06 EP EP05011119A patent/EP1574794B1/en not_active Expired - Lifetime
- 2001-07-06 EP EP01116409A patent/EP1170558B1/en not_active Expired - Lifetime
Cited By (8)
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US20120011872A1 (en) * | 2009-02-27 | 2012-01-19 | Danfoss Commercial Compressors | Device for separating lubricant from a lubricant-refrigerating gas mixture discharged from at least one refrigerant compressor |
US9207005B2 (en) * | 2009-02-27 | 2015-12-08 | Danfoss Commercial Compressors | Device for separating lubricant from a lubricant-refrigerating gas mixture discharged from at least one refrigerant compressor |
US20120006041A1 (en) * | 2009-03-31 | 2012-01-12 | Takashi Ikeda | Refrigerating device |
US9541313B2 (en) * | 2009-03-31 | 2017-01-10 | Mitsubishi Electric Corporation | Refrigerating device |
US20120023978A1 (en) * | 2010-07-28 | 2012-02-02 | Chae Sunam | Refrigerator and driving method thereof |
US9146046B2 (en) * | 2010-07-28 | 2015-09-29 | Lg Electronics Inc. | Refrigerator and driving method thereof |
CN102865213A (en) * | 2011-07-08 | 2013-01-09 | 珠海格力电器股份有限公司 | Multi-compressor system and oil balancing method and device thereof |
US11713760B2 (en) * | 2017-12-28 | 2023-08-01 | Emerson Climate Technologies (Suzhou) Co., Ltd. | Intake pipe used for compressor system and compressor system |
Also Published As
Publication number | Publication date |
---|---|
DE60113601D1 (en) | 2006-02-09 |
DE60113601T2 (en) | 2006-06-22 |
CN1187559C (en) | 2005-02-02 |
TWI237682B (en) | 2005-08-11 |
EP1170558A2 (en) | 2002-01-09 |
EP1170558B1 (en) | 2005-09-28 |
EP1170558A3 (en) | 2002-10-23 |
EP1574794A1 (en) | 2005-09-14 |
KR100807498B1 (en) | 2008-02-25 |
US6446462B1 (en) | 2002-09-10 |
CN1510361A (en) | 2004-07-07 |
KR20020005411A (en) | 2002-01-17 |
EP1574794B1 (en) | 2007-03-14 |
CN1260533C (en) | 2006-06-21 |
CN1333450A (en) | 2002-01-30 |
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