CN104641117B - Active oil management method for multiple screw compressors - Google Patents

Abstract

The method of multiple compressor operation refrigeration systems that a kind of utilization is connected in parallel.Described method includes cold-producing medium and oil are back to described compressor, described cold-producing medium also has the oil carried secretly in the refrigerant, make to be entrained in described cold-producing medium is described separating of oil, the most operate regardless of the leading compressor of the plurality of compressor, be all back to the leading compressor of the plurality of compressor by being entrained in more described oil in described cold-producing medium.Described method also includes that the oil sump making all of compressor in the plurality of compressor connects so that make oil from described leading compressor supply at least one non-dominant compressor described when at least one non-dominant compressor of the plurality of compressor is in operation.

Description

Active oil management method for multiple screw compressors

Technical field

The present invention relates generally to a kind of Multi-compressor refrigeration system.

Background technology

About the concrete example of the prior art of air-breathing distribution in parallel compressor assembly with WIPO patent Open source literature WO2008/081093 (air-breathing assigned unit in parallel compressor assembly and Parallel compressor assembly) it is representative, the document illustrates has two or more compressors For the distributor of air-breathing in system, the teaching of the document and be disclosed in this in way of reference the most also Enter.There is the concrete example of oil management in the system of multiple compressor at american documentation literature Disclosed in 4,729,228 (for the suction line stream separator of parallel compressor installations), the document Instruct and be disclosed in this and be fully incorporated in way of reference.

Embodiments of the invention described herein represents the improvement of prior art.The present invention these and Further advantage and additional inventive features are by aobvious and easy from the description of the present invention provided herein See.

Summary of the invention

In one aspect, embodiments of the invention provide multiple compressors behaviour that a kind of utilization is connected in parallel The method making refrigeration system.Described method includes cold-producing medium and oil are back to described compressor, described Cold-producing medium also has the oil carried secretly in the refrigerant, and make to be entrained in described cold-producing medium is described separating of oil, The most operate regardless of the leading compressor of the plurality of compressor, all will be entrained in described cold-producing medium In more described oil be back to the leading compressor of the plurality of compressor.Described method also includes making In the plurality of compressor, the oil sump of all compressors is connected as when at least one of the plurality of compressor Non-dominant compressor makes oil from described leading compressor supply at least one non-master described when operation Lead compressor.

Furthermore, described method can include setting be configured to described leading compressor supply than to Any non-dominant compressor of the plurality of compressor is supplied the suction head of more oil, is also referred to as Common supply line.It is each that the embodiment of described method farther includes the plurality of compressor Entrance arranges single entrance supply line, wherein, to described leading compressor supply more oil bag Include the described entrance supply line of restricted guidance each non-dominant compressor.And described entrance is supplied The restriction of pipeline may be designed as compared with the suction pressure of the porch of leading compressor, in described non-master The described porch leading compressor produces the suction pressure reduced.In certain embodiments, each compression Cold-producing medium and oil are drained into common discharge line by machine.

In certain embodiments, described method builds refrigeration system by being connected by multiple compressor parallels System.Further embodiment of the present invention is included on identical horizontal position or positions each pipe on oil sump position Pipe connecting.Additionally, in a particular embodiment, described method includes that location is by each conduit coupling Being positioned so as to the most described leading compressor the most operate, oil will be by described pipeline from described Leading compressor flow at least one the non-dominant compressor operated.This flowing will continue to stating master Lead the oil sump pressure in the oil sump of compressor and at least one non-dominant compressor described approximately the same.

In a particular embodiment, described method includes making the institute of all compressors in the plurality of compressor State oil sump and be connected such that oil does not has when the non-dominant compressor of the plurality of compressor is not in operation It flow to described non-dominant compressor from described leading compressor.In this case, described oil does not flow The rising of the oil sump pressure in described non-dominant compressor it is because to described non-dominant compressor.

On the other hand, embodiments of the invention provide a kind of refrigeration system, and this refrigeration system includes also Multiple compressors that connection connects.The plurality of compressor includes at least one leading compressor, and often Individual compressor has compressor housing.Have for by cold-producing medium and oil supply extremely the plurality of compressor Each common supply line.Described common supply line is configured to the institute with the plurality of compressor Stating at least one non-dominant compressor to compare, more oil is back at least one leading compression described. Each compressor has opening, and each opening structure on the bottom of its respective compressor housing For allowing oil flow to the oil sump of its respective compressor or flow out from the oil sump of its respective compressor.Enter One step ground, each opening is connected to pipeline so that each described oil sump stream of the plurality of compressor Body connects.Further, each opening is positioned so as to the most described leading compressor and the most operates, Described oil can distribute any described non-dominant to the plurality of compressor from described leading compressor Compressor.

In the specific embodiment of the invention, no matter dominate compressor and the most operate, described leading pressure Contracting machine is all by appointing in oil distribution to the described non-dominant compressor operated of the plurality of compressor Meaning compressor.In certain embodiments, the plurality of compressor each has and is connected to jointly supply The entrance supply pipe of pipeline, and, except leading compressor, at least one non-dominant compressor described In the entrance supply line of any compressor there is limiter to reduce the inflow compressor of oil.At tool In body embodiment, the described limiter structure on described entrance supply line is at its respective compressor Porch produce reduce suction pressure.

Furthermore, it is contemplated that embodiments of the invention include multi-compressor system, in this system In each compressor there is different performances.The most each compressor has different volume indexs Multiple compressors use in US patent application publication filed in 22 days January in 2010 Disclosed in 2010/0186433 (there is screw compressor and its system and method for different volume index), Teaching and the disclosure of the document are incorporated in way of reference in this as entirety.

In another aspect, embodiments of the invention provide a kind of multiple compressors including being connected in parallel Refrigeration system.The plurality of compressor includes at least one leading compressor, and each compressor There is compressor housing.Have for by cold-producing medium and oil supply extremely at least one leading compressor described Supply line, described cold-producing medium and oil from least one leading compressor supply described to the plurality of One or more non-dominant compressors of compressor.Each compressor is at its respective compression case Having opening on the bottom of body, each opening is constructed to allow for oil and flow to the oil sump of its respective compressor Or flow out from the oil sump of its respective compressor.Further, each opening be connected to pipeline so that Obtain each described oil sump fluid communication of the plurality of compressor.Further, each opening is orientated as and is made Obtaining the most described leading compressor the most to operate, described oil can distribute from described leading compressor Any compressor to the one or more than one non-dominant compressor of the plurality of compressor. In a particular embodiment, described leading compressor has the vertical head being connected to described supply line, Described vertical head configuration is that oil enters the oil sump of described leading compressor.

The other side of the present invention, target and advantage will become more from following detailed description when connection with figures Add substantially.

Accompanying drawing explanation

Described accompanying drawing that is that the present invention is incorporated to and that constitute the present invention a part of shows the multiple of invention Aspect, and these accompanying drawings combine description for illustrating spirit of the invention.In the drawing:

Fig. 1 is the block diagram of the Multi-compressor refrigeration system according to embodiments of the invention structure；

Fig. 2 is the sectional view of the screw compressor according to embodiments of the invention structure；

Fig. 3 is the sectional view of the screw compressor of the alternate embodiment structure according to the present invention；

Fig. 4 is the front perspective view of the suction tube according to embodiments of the invention structure；

Fig. 5 is the rear view of the suction tube of Fig. 4；

Fig. 6 is the schematic diagram of the Multi-compressor refrigeration system according to embodiments of the invention structure；

Fig. 7 is the Multi-compressor refrigeration system of the alternate embodiment structure according to the present invention；

Fig. 8 is the schematic diagram of the common supply line according to embodiments of the invention；

Fig. 9 is the schematic diagram of the common supply line with oil eliminator according to embodiments of the invention； And

Figure 10 is the sectional view of the compressor assembly with vertical head according to the present invention.

Although the present invention will be described by conjunction with some preferred implementations, but it is not intended to be confined to Those embodiments.Conversely, contain by appended power due to all of replacement, remodeling and equivalence In profit requires the purpose and scope of the invention limited, therefore the invention is intended to cover all these and replace Generation, remodeling and equivalence.

Detailed description of the invention

Following detailed description describes the embodiment that the present invention applies in Multi-compressor refrigeration system.So And, it will be recognized by those of ordinary skill in the art that the present invention may be not necessarily limited to refrigeration system.The present invention Embodiment also can be used in multiple compressors are used to other system of flow of the compressed gas.

Fig. 1 provides the schematic diagram of the exemplary Multi-compressor refrigeration system 1 with N number of compressor 6. N number of compressor 6 of refrigeration system 1 is connected in shunt circuit, has to N number of in this shunt circuit Compressor 6 provides the feed line 3 of cold-producing medium stream and the cold-producing medium of carrying compression to leave N number of compressor The outflow pipeline 5 of 6.In certain embodiments, cold-producing medium stream carries oily together with cold-producing medium, described Oil is for lubricating the mobile parts of compressor 6.As it can be seen, flow out pipeline 5 to supply condenser 7.? In specific embodiment, condenser 7 includes providing through condenser 7 to cool down and thus to condense compression The fluid stream heat exchanger 9 (such as air or liquid coolant) of one of high-pressure refrigerant flowing.

There is provided the evaporation element 11 of cooling also in condenser 7 downstream fluid arranged in series.Implement substituting In example, condenser 7 can supply multiple evaporation element being arranged in parallel.In the embodiment in figure 1, steam Bill unit 11 includes closing liquid valve 13, closes liquid valve 13 in certain embodiments by refrigeration system control Device 15 controls to allow the evaporation of evaporation element 11 thus the demand load needs in refrigeration system 1 Time produce cooling or be not evaporated the evaporation operation of unit 11 when there is no such demand.Refrigeration System controller 15 also may be connected directly to one or more of N number of compressor 6.Evaporation element 11 also include expansion valve 17, this expansion valve in response to or part be controlled by the downstream of evaporation element 11 The pressure of sensing at position 19.Expansion valve 17 is configured to control the cold-producing medium row to evaporation element 11 Enter, in evaporation element, due to evaporation, heat absorbed so that cold-producing medium be evaporated to gaseous state thus Cooling/refrigeration effect is produced on evaporation element 11.Evaporation element 11 by the expanding refrigerant of gaseous state along Feed line 3 is back to the combination of N number of compressor 6.

It should be noted that, for convenience, embodiments of the invention are hereinafter often having with regard to them Multiple application in the system of the screw compressor compressing cold-producing medium is had to be described by.Although it is concrete Advantage and structure illustrate for turbo-compressor, but some in these embodiments are not limited to whirlpool Wheel compression machine, and other many kind the beyond screw compressor has purposes in compression.

It is shown in fig. 2, wherein, Fig. 2 illustrates cuing open of compressor assembly 10 to embodiments of the invention View, this compressor assembly 10 generally comprises shell 12, and compressor apparatus 14 is driven in shell 12 Moving cell 16 drives.In the example embodiment being described below, compressor apparatus 14 is scroll compression Contracting machine.Thus, term " compressor apparatus " and " screw compressor " the most sometimes may be used Exchange and use.Compressor assembly 10 may be provided at for freezing, industry cooling, freezing, air-conditioning or its In refrigerant loop in the suitably application that the fluid of its compression is required.Suitably connector provides Connecting and including that the refrigerant inlet 18 extending through shell 12 and cold-producing medium go out to refrigerating circuit Mouth 20.Compressor assembly 10 can be operated by the operation of driver element 16, thus operates compression Machine equipment 14 and thus compression enter refrigerant inlet 18 and leave system with the high pressure conditions of compression The suitable cold-producing medium of cryogen outlet 20 or other fluid.

Shell body 12 can take many forms.In the detailed description of the invention of the present invention, shell body 12 Including multiple shell segments or shell section, and in certain embodiments, shell body 12 includes central authorities' tubular Shell section 24, tip shell section 26 and bottom shell section or base plate 28.In a particular embodiment, shell Body section 24,26,28 is formed by suitable steel plate and is welded together thus forms permanent housings body 12 encasements.However, if it is desired to split if shell body 12, be used for being attached shell section 24,26, 28 and the method for non-solder can be employed, these attachment methods including, but not limited to soldering, use spiral shell Stricture of vagina securing member or the machinery of other be suitably used for being attached shell 12 each section.

Central authorities' shell section 24 is preferably tubular or cylindrical shape and can be with tip shell section 26, bottom shell Body section 28 abuts or expansion fit.As visible in the embodiment at Fig. 2, demarcation strip 30 is arranged on top In shell section 26.In an assembling process, these components can be assembled as so that when tip shell section 26 When being connected to central cylindrical shell section 24, around the single welding of shell 12 circumference by tip shell Section 26, demarcation strip 30 and central cylindrical shape shell section 24 link together.Tip shell section 26 is general For arch and include cylinder side wall district 32 with central authorities shell section 24 mate and shell 12 be provided The closing on top, the most in a particular embodiment, bottom shell section can be arch, cup-shaped or greatly Cause smooth.As in figure 2 it is shown, the assembling of shell 12 causes surrounding driver element 16 and partially wrapping Enclose the formation of the closed cavity 31 of compressor apparatus 14.

Screw compressor 14 in the present invention is arranged in the one exemplary embodiment in shell 12, vortex Compressor 14 includes the first scroll and the second scroll, described first, Two scroll preferably include static fixed scroll compressor body 110 and removable vortex Compressor body 112..The most substantially meaning " fixed " in term is static or not Removable, more specifically " fix " and refer to do not have track to move, there is no powered scroll member, And as known, some narrow axially-movable, radial motion and rotary motions by It is possible in thermal expansion and/or design tolerance.

Removable scroll 112 is arranged with respect to fixed scroll compressor body 110 rail Road moves with in order to compress cold-producing medium.Fixed scroll compressor body includes from platy substrate 116 axial Highlight, be generally positioned to be the first rib 114 of spiral form.Similarly, removable scroll 112 include axially projecting from platy substrate 120 and for similar swirl shape the second scroll rib 118.Scroll rib 114,118 is engaged with each other and in the substrate 120 of another compressor body 112,110, Seal against on the corresponding surface of 116.

In a particular embodiment of the present invention, driver element 16 is the form of electric machine assembly 40.Motor Assembly 40 operationally rotates and driving shaft 46.Further, electric machine assembly 40 generallys include Have the stator 50 of electric coil be connected to driving shaft 46 for together with the rotor 52 that rotates.Stator 50 directly or are supported by shell 12 by adapter.Stator 50 can directly by be press-fitted into shell 12, Or coordinate and by being press-fitted into shell 12 with adapter (not shown).In a particular embodiment, turn Son 52 is arranged in the shaft member 46 supported by upper and lower parts of bearings 42,44.

To stator 50 energising can operatively around central axis 54 rotate drive rotor 52 and by This rotating driveshaft part 46.Applicant it is pointed out that and exists when term " axially " and " radially " When this is used to the feature describing component or assembly, they are defined with regard to central axis 54.Specifically, Term " axially " or " axially extending " refer to along the direction of central axis 54 or are parallel to center The feature that axis 54 highlights or extends, and term " radially " or " radially extending " show be perpendicular to The feature that the side of central axis 54 projects upwards or extends.

In a particular embodiment, lower bearing parts 44 include central authorities, the hub 58 of general cylindrical shape, institute State hub 58 include central sleeve and opening to provide cylindrical bearing 60, driving shaft 46 with axle journal pacify It is loaded on cylindrical bearing 60 for rotating support.The district of tabular spine 68 of lower bearing parts 44 is from central authorities Hub 58 projects radially outward and for the lower part of stator 50 being separated with lubricating oil bath 76.Lower axle The axially extending boundary 70 of bearing portion part 44 can engage with the internal diameter face of central shell section 24 with between two parties Ground positions lower bearing parts 44 and keeps the position of lower bearing parts 44 thus relative to central axis 54 Put.This can be by the interference fit between lower bearing parts 44 and shell 12 with by the support of press-fit Structure realizes.

As from the embodiment of Fig. 2, driving shaft 46 includes being attached to driving shaft 46 bottom Impeller tube 47.In a particular embodiment, the diameter of impeller tube 47 is less than driving shaft 46, and with Central axis 54 concentric alignment.Driving shaft 46 and impeller tube 47 pass in lower bearing parts 44 The opening of centre hub 58.Impeller tube 47 has grease channel and is formed at the entering of end of impeller tube 47 Mouth 78.

In its upper end, driving shaft 46 is installed with axle journal in upper bearing (metal) parts 42 and is used for rotating. Hereinafter, upper bearing (metal) parts 42 are also referred to as " bent axle set ".In a particular embodiment, drive shaft Part 46 farther includes to be generally of the cylinder around the biasing axis biased relative to central axis 54 The biasing eccentric drive section 74 of shape drive surface.This biasing drive section 74 at screw compressor 14 can Install with axle journal in the center hub 128 of mobile scroll 112, for when driving shaft 46 Removable scroll 112 is driven around orbital path when rotating around central axis 54.For Thering is provided lubrication to all of each bearing surface, shell 12 is provided with lubricating oil bath in the bottom of shell 12 76, in lubricating oil bath 76, proper amount of lubricating oil is stored.

Also as can be seen Fig. 2 and illustrate the reality of the suction tube 300 used in screw compressor assembly 10 Execute example.In certain embodiments, suction tube 300 is included in the flow path by refrigerant inlet 18 In and with motor 40 be around relation position plasticity molding ring body 302.Suction tube 300 It is set to be guided by cold-producing medium and be inducted into motor cavity be used for cooling down motor 40 and leach from lubricating oil miscellaneous simultaneously Matter and lubricating oil imported oil sump 76 around the circumference of suction tube 300.

Additionally, in a particular embodiment, suction tube 300 includes the screen part 308 being positioned in opening 304, When refrigerant gas enters compressor by entrance 18, described screen part 308 filters refrigerant gas, as Shown in Fig. 2.Screen part 308 is generally made up of metal gauze such as stainless (steel) wire, each hole of screen part 308 It is typically sized to 0.5 to 1.5 millimeter.

As shown in Figure 2 and as it has been described above, suction tube 300 and motor 40 be to position around relation ground, And in certain embodiments, suction tube 300 include with the inner surface of general cylindrical shape shell 12 faced by The generally arcuate outer surface of face contact.In a particular embodiment, suction tube 300 is included in shell 12 He The sealing surface (as shown in Figure 3) substantially sealed is formed between suction tube 300.Sealing surface can cincture and close Fengkai mouth 304 is to guarantee that cold-producing medium flows into motor cavity.This sealing can be aeroseal, but not necessarily So.This sealing will typically ensure that the refrigerant gas more than 90% and the cold-producing medium of preferably at least 99% Gas is by screen part 308.By the tool between the part of entrance 18 at sealing surface and shell body 12 Having sealing, suction tube 300 can filter bigger granule from the refrigerant gas entered by entrance 18, The refrigerant gas being therefore prevented from filtered enters compressor, and can be by cold-producing medium relatively low for temperature Importing motor cavity preferably cools down for motor 40 and is directed downwardly in oil sump 76 by oil simultaneously.

During operation, the refrigerant gas cold-producing medium than the compression at outlet 20 of entrance 18 is flowed into Gas temperature is low.Furthermore, in the operation of screw compressor 14, the temperature of motor 40 Will raise.Therefore, expect to cool down motor 40 in the operation of compressor.To this end, by entrance 18 The refrigerant gas that the temperature of suction compressor case 12 is relatively low passes and flows up along motor 40 Thus arrive screw compressor 14, thus motor 40 is cooled down.

Still further, impeller tube 47 and entrance 78 are being used as oil pump when driving shaft 46 rotates, And thus oil is pumped out and is pumped into the inside profit limited in driving shaft 46 from lubricating oil bath 76 In oil pathway 80.In the operation of driving shaft 46, centrifugal force is used for driving the effect of antigravity Dynamic lubricating oil is upwardly through grease channel 80.Grease channel 80 has multiple from grease channel 80 prominent radial passages to be supplied to suitable bearing surface and thus according to needing by centrifugal force by oil Slidingsurface to be lubricated.

Fig. 3 illustrates the sectional view of the alternate embodiment of compressor assembly 10.In figure 3, can see The fluid stream (such as cold-producing medium) guiding to be come in is can be used as by housing inlet port 18 to suction tube 234. For inlet porting 18, shell 12 includes entering opening, and inlet fitting 312 is arranged on this entrance opening In.In the specific embodiment shown in Figure 4 and 5, suction tube 234 include having constant wall thickness and Having the stamping steel plate metal body of the substantially rectangular outer mounting flange 320 with arc, described installation is convex Edge 320 is looped around between top 324 and bottom 326 the pipe path 322 extended.Enter opening and entrance Mouth 318 is formed through bottom the path on top 324 328.This enters opening and inlet port 318 Connect from entrance 18 and compressor is passed through in reception by sucking screen part flange 316 (figure 3 illustrates) Shell wall receive and receive the fluid of pipe path 322 entering suction tube 234.

Pipe path outlet 330 on the bottom 326 of suction tube 234 or near bottom 326 provides Fluid flow path.In this embodiment, outlet 330 extends through bottom 326 and thus The mouth that lubricating oil enters lubricating oil bath 76 is provided, and this mouthful also will be used for the big of the cold-producing medium of compression Cause bulk flow and be communicated to be located just at the position of the upstream of electric machine casing.

Suction tube 234 is not only used to guide to motor the substantially bulk flow of cold-producing medium and oil from entrance 18 The position of 40 upstreams and guide fluid to flow through motor 40, and also it is used as gravity comb, this is heavy Power comb is preferably by being positioned at bottom the absolute gravity of suction tube 234 place or close to bottom absolute gravity The lubricating oil received in suction tube 234 is entered lubricating oil bath 76 by the outlet 330 at place.This point due to Many reasons is useful.First, when needing filling lubricating oil bath in the case of initial launch or other When 76, oil can easily add by also serving as the entrance 18 of oil charging port, thus oil flows through naturally Suction tube 234 and enter oil sump 76 by outlet 330.Thus shell 12 can need not individually Hydraulic fluid port.Additionally, the direction of the oil in the surface of suction tube 234 and suction tube 234 changes causes lubrication The gathering of mist of oil, the lubricant mist of gathering can be collected and subsequently by discharging in pipe path 322 Mouth 330 is expelled back in oil sump 76.Thus, the direction of cold-producing medium and the direction of lubricating oil are at suction tube It is established in 234.

During operation, screw compressor assembly 10 can be operable at housing inlet port 18 receive Low pressure refrigerant and compress cold-producing medium and be used for being delivered to high pressure chest 180, at high pressure chest 180 inner refrigerant Can be exported by housing outlets 20.As shown in Figures 2 and 3, suction tube 234,300 is arranged on shell 12 is internal to be inducted in shell 12 from entrance 18 by low pressure refrigerant and to guide under electric machine casing Side.This allows low pressure refrigerant to flow through and stride across motor 40, and thus cooling motor 40 and from Heat taken away by motor 40.Then low pressure refrigerant can pass through multiple electric machine casings 48 towards cold-producing medium (as shown in Figure 3) on electric machine casing outlet or upper bearing (metal) parts 42 on outlet leave top, Longitudinally through electric machine casing and through the clearance space in electric machine casing.After leaving electric machine casing outlet, Low pressure refrigerant enters the annular compartment 242 formed between electric machine casing 48 and shell 12 (such as Fig. 3 Shown in).Afterwards, low pressure refrigerant can pass across or through upper bearing (metal) parts 42.

After by upper bearing (metal) parts 42, low pressure refrigerant finally enter scroll 110, The entrance district 124 of 112.From entering district 124, low pressure refrigerant is progressively compressed directly by chamber 122 At compression outlet 126, its most compressed state is reached to cold-producing medium, after compression outlet 126, Cold-producing medium is through check-valves and enters high pressure chest 180.From high pressure chest 180, high pressure compressed cold-producing medium can Screw compressor assembly 10 is left by outlet 20.

Fig. 6 and 7 be illustrate Multi-compressor refrigeration system 200,220, multi-compressor system such as Fig. 1 The schematic diagram of two embodiments of cooling system.In the refrigeration system 200 of Fig. 6, compressor #1, #2 Link in parallel with #3 202.In a particular embodiment of the present invention, compressor 202 is and Fig. 2 and 3 The screw compressor that the compressor shown is similar or identical.But, in alternative embodiments, scroll compression Compressor beyond contracting machine can be used.Furthermore, the embodiment of Fig. 6 illustrates and has three The refrigeration system 200 of compressor 202, but, the alternate embodiment of the present invention also can have than three pressures The more or less of compressor of contracting machine.

For compressor #1, #2 and #3 202, by having the compressor 202 of independent oil sump 76 structure The internal flow of cold-producing medium form the pressure of oil sump 76 from suction inlet 18 to the compressor of each operation Decline, this is because what gas flow restriction caused.When any one of these compressors 202 is closed When closing and do not have flow restriction, oil sump 76 pressure will have identical suction pressure relative to run Compressor higher.Between the oil sump 76 of the oil sump 76 of the compressor run and the compressor of closedown Pressure differential allows refrigeration system 200,220 from the compressor closed to the oil distribution of the compressor run.

In the structure of Fig. 6 and 7, compressor #2 202 takes compressor as the leading factor.Although three compressors 202 all receive cold-producing medium stream and by cold-producing medium from suction head, also referred to as common supply line 204 Enter common discharge line or conjoint outlet pipeline 205 (only figure 6 illustrates), common supply line 204 are configured to compared with non-dominant compressor #1 and #3 202 carry more to leading compressor #2 202 Lubricating oil.In certain embodiments, this is to guide non-master by restriction from common supply line 204 Lead the entrance supply line 208 of compressor #1 and #3 202 thus limit the oil to these compressors Flow and realize.But, as it is shown in fig. 7, this realizes also by arranging oil eliminator 206, Most of oil out and are passed through oil delivery pipe from cold-producing medium flow separation by oil by this oil eliminator 206 207 are delivered to leading compressor #2 202.Further, more oil is back to leading compressor #2 202 Other method can be used, these methods include different pipeline flowing and are returned directly to by oil main Lead the various types of separating of oil equipment of oil sump 76 of compressor #2 202.As it has been described above, suction line bag Include the pressure making suction inlet 18 (as shown in Figures 2 and 3) place of non-dominant compressor #1 and #3 202 produce Force rate dominates the limiter that the pressure at the suction inlet 18 of compressor #2 202 is low.

Fig. 8 and 9 is the schematic diagram of exemplary pipeline flowing.As described in Figure 8, leading compressor is guided The entrance supply line 208 of #2 202 is than the entrance supply pipe guiding non-dominant compressor #1, #3 202 Road 208 is bigger.Furthermore, guide the entrance supply line 208 of leading compressor #2 202 with Common supply line 204 aligns, and guides the entrance supply line of non-dominant compressor #1, #3 202 208 become the angle of about 90 degree with common supply line 204.This configuration will cause cold-producing medium and oil stream In more oil flow to leading compressor #2 202.Additionally, flow to non-dominant compressor #1, #3 202 Oil stream by be positioned at guide non-dominant compressor #1, #3 202 entrance supply line 208 in restriction Device 211 reduces further.These limiters 211 are for reducing non-dominant compressor #1, #3's 202 The suction pressure at entrance 18 (as shown in Figures 2 and 3) place, so that non-dominant compressor #1, #3 202 Entrance 18 at the suction pressure suction inlet 18 less than leading compressor #2 202 at pressure.

Fig. 9 illustrates the pipeline flowing different from shown in Fig. 8.In this embodiment, separating of oil Device 209 is arranged in common supply line 204.Oil eliminator 209 can include that steel mesh is to collect refrigeration Entrained oil in agent stream.Alternatively, fiber filter medium can be used to from cold-producing medium flow separation oil.Such as Fig. 9 Shown in, once oil is extracted from cold-producing medium by oil eliminator 209, then oil can import entrance supply pipe Road 208 is used for dominating compressor #2 202.Fig. 9 illustrates gravity and can be used to assist oil to flow into leading pressure Contracting machine #2 202.As seen from Figure 9, the most lesser amount of oil guides non-around oil eliminator 209 inflow The entrance supply line 208 of leading compressor #1, #3 202.As it can be seen, guide non-dominant compressor The entrance supply line 208 of #1, #3 202 include limiter 211 for reduce non-dominant compressor #1, The suction pressure at entrance 18 (as shown in Figures 2 and 3) place of #3 202, so that non-dominant compression The suction pressure at the entrance 18 of machine #1, #3 202 suction inlet 18 less than leading compressor #2 202 The suction pressure at place.

Another embodiment of the present invention illustrates at Figure 10, and wherein, Figure 10 is at leading compressor 202 Housing in the sectional view of refrigeration system of head 301 is set.Two compressors 202 show in Fig. 10 Go out, but the configuration in Figure 10 can use in the refrigeration system with two or more compressor 202. In the embodiment in figure 10, in cold-producing medium stream and cold-producing medium stream, entrained oil is only supplied only to leading compression Machine 202, cold-producing medium is allocated other non-dominant compressor any to system from leading compressor 202 202.Cold-producing medium and oil flow into the mouth 303 on compressor housing top and flow into head 301, head 301 are directed downwardly into oil sump 76.Oil separates from cold-producing medium in head 301.Isolated oil enters oil Pond 76.Cold-producing medium flows to head less than 301 and some cold-producing mediums flow into the pressure dominating compressor 202 Contracting equipment, and remaining cold-producing medium from compressor housing bottom second mouthful 305 outflow and by pipe The non-dominant compressor 202 that road 306 flow in system.

Referring again to Fig. 6 and 7, the shell 12 that each compressor 202 has through it (sees Fig. 2 With 3) lead to the opening 210 of the oil sump 76 (seeing Fig. 2 and 3) of compressor 202.Pipeline 212 is even It is connected to each opening 210 so that for all of oil sump 76 of compressor #1, #2 and #3 202 It is in fluid communication by pipeline 212.In a particular embodiment of the present invention, each opening 210 is positioned at pressure On the shell body 12 of contracting machine 202 on approximately uniform position.Each opening 210 can be located at identical water Putting down above or being positioned at makes the position representative of each opening 210 can be distributed to by its oil at compressor 202 The specific water of the minimum oil level that should retain in oil sump 76 before other compressor 202 is put down. Locating aperture 210 allows oil to be flow to from leading compressor #2 202 by pipeline 212 in this way Other needs the compressor 202 operated of oil.

In the embodiment shown in Fig. 6 and 7, common supply line 204 is configured to more oil from system Cryogen stream is back to leading compressor #2 202.Oil level when the oil sump 76 of leading compressor #2 202 It is increased to more than the level of opening 210 and (assumes that these are pressed at non-dominant compressor #1 and #3 202 Contracting machine run) in level more than time, then the oil sump pressure dominating compressor #2 202 can compare non-master The oil sump pressure leading compressor #1 and #3 202 is higher, thus allows oil by pipeline 212 from leading pressure Contracting machine #2 202 flow to non-dominant compressor #1 and #3 202.If the oil in leading compressor #2 202 It is high that pond pressure ratio receives the oil sump pressure in compressor 202, and no matter this flowing dominates compressor #2 202 Whether run and all can occur.In certain embodiments, oil will continue distribution by this way until dominating Compressor #2 202 and the oil sump pressure received in compressor 202 are approximately the same.But, work as non-dominant In compressor #1 and #3 202 one or two the most operationally, the compressor not running or not operating The oil sump pressure of the increase in 202 stops oil to flow to the compressor not run from leading compressor #2 202 202。

There is provided more oil to leading compressor #2 202 and pipeline be configured at non-dominant compressor #1 Enough oil distribution will be made many to this with the combination producing the pressure reduced at the entrance 18 of #3 202 All compressor #1, #2 and #3 202 of compressor set, whether connect regardless of each compressor or Power-off.Additionally, in a particular embodiment, the flowing from this oil of leading compressor #2 202 will Continue to compressor #2 202 and the pressure received in the non-dominant compressor that oil flows equal.This is at table 1 In operation matrix shown in.

Table 1:I=connects；O=disconnects

Above-mentioned matrix (table 1) shows in the refrigeration system of Fig. 6 and 7 when the compressor run needs oil Time the allocated mode of oil.As from above-mentioned matrix, as all of compressor #1, #2 and #3 202 If operationally or leading compressor #2 202 disconnects and non-dominant compressor #1 and #3 202 During operation, leading compressor #2 202 is as required by distribution of lubrication oil to non-dominant compressor #1 and #3 202.Disconnect or compressor #1 202 and leading compressor #2 202 all disconnects at compressor #1 202 In the case of, lubricating oil is provided to non-dominant compressor #3 202 by leading compressor #2 202.On the contrary, When disconnecting as compressor #3 202 or all disconnect as compressor #3 202 and leading compressor #2 202, Lubricating oil is provided to non-dominant compressor #1 202 by leading compressor #2 202.Finally, when leading compression When machine #2 202 runs and non-dominant compressor #1 and #3 202 all disconnects, leading compressor #2 202 Any lubricating oil is not provided to non-dominant compressor #1 and #3 202.

Including disclosure, patent application and herein cited patent all of reference at this with each ginseng Examine by individually and particularly point out and be incorporated in way of reference with each reference in this article with its entirety quilt Being expressly incorporated herein by reference mode of the identical degree proposed.

Unless otherwise indicated herein or context is clearly contradicted, otherwise (special at the comment of the present invention Be not in the claims below word) in term " ", " one " with " described " with similar The use of term should be interpreted that and not only includes odd number but also include plural number.Term " includes ", " having ", " bag Contain " and " containing " unless otherwise stated, should be construed to open-ended term (i.e. mean " bag Include but be not limited to ").Unless otherwise indicated herein, only the enumerating of scope of value the most herein It is provided merely as respectively with reference to the method for simplifying of each independent value fallen within the above range, and often Individual independent value is incorporated herein as it is individually enumerated in this article.Unless the most separately had Illustrating or context is clearly contradicted, otherwise all methods described herein can be suitable be arbitrarily suitable for Sequence is implemented.Unless otherwise stated, the most provided in this article any and all embodiment or exemplary language The use of speech (such as " as ") is merely intended to preferably to illustrate the present invention and not model to the present invention Enclose and limit.Language in the present invention is all not construed as referring to the enforcement to the present invention to closing weight The component of any non-declarative wanted

The preferred embodiment of the present invention is described in this article, it include that inventor knows for reality Execute the optimal mode of the present invention.For those of ordinary skill in the art, those are preferable to carry out As long as will become apparent from of preceding description is read in the deformation of mode.Inventor expects technical staff It is appropriately carried out these deformation, and inventor wishes that the present invention is with the method beyond specifically describing herein It is practiced.Thus, as applicable law allows, the present invention includes the claim being invested this The all of remodeling of the theme enumerated and equivalence.Additionally, unless otherwise indicated herein or upper and lower civilization Aobvious contradiction, component the most described above with its likely modification and any combination of being formed by this Bright contain.

Claims (20)

1. a method for multiple compressor operation refrigeration systems that utilization is connected in parallel, described method bag Include:

Cold-producing medium and oil are back to described compressor, and described cold-producing medium also has to be carried secretly in the refrigerant Oil；

Make to be entrained in described cold-producing medium is described separating of oil；

The most operate regardless of the leading compressor of the plurality of compressor, all will be entrained in described system In cryogen, more described oil is back to described leading compressor；

The oil sump of compressors all in the plurality of compressor is connected so that when the plurality of compressor At least one non-dominant compressor operation time make oil from described leading compressor supply to described at least one Individual non-dominant compressor；

Common supply line is set；And

Compared with any non-dominant compressor of the plurality of compressor, to described leading compressor supply More oil；

Each entrance of the plurality of compressor is arranged single entrance supply line, wherein, to Described leading compressor supply more oil includes limiting the entrance supply leading to each non-dominant compressor Pipeline.

Method the most according to claim 1, wherein, is limited in described entrance supply line The described porch of described non-dominant compressor produces the suction pressure reduced.

Method the most according to claim 1, described method further includes at described common supply Arranging oil eliminator in pipeline, described oil eliminator is configured to more compared with described non-dominant compressor Many oil is directed at described leading compressor.

Method the most according to claim 1, described method farther includes to be connected in parallel multiple whirlpool Rotation compressor.

Method the most according to claim 1, described method further includes at identical horizontal position Above or position each conduit coupling on oil sump position.

Method the most according to claim 5, wherein, positions each conduit coupling and includes often Individual conduit coupling is positioned so as to the most described leading compressor and the most operates, and all makes oil pass through Pipeline flow at least one the non-dominant compressor operated from described leading compressor, until described Oil sump pressure in the oil sump of leading compressor and at least one non-dominant compressor described is approximately the same.

Method the most according to claim 1, wherein, cold-producing medium and oil are drained into by each compressor Common discharge line.

Method the most according to claim 1, wherein, by compressions all in the plurality of compressor The oil sump of machine connects and includes that making the oil sump of all compressors in the plurality of compressor be connected such that works as institute Stating the non-dominant compressor of multiple compressor not when operation, oil does not flow to from described leading compressor This non-dominant compressor, wherein, oil does not flow to this non-dominant compressor and is because the compression of this non-dominant The rising of the oil sump pressure in machine.

Method the most according to claim 1, wherein, is back to described compressor bag by cold-producing medium Including the head that cold-producing medium is back to described leading compressor, cold-producing medium is supplied to described many from this head Remaining compressor of individual compressor.

10. a refrigeration system, comprising:

The multiple compressors being connected in parallel, the plurality of compressor include at least one leading compressor and At least one non-dominant compressor, each compressor has compressor housing；

For supplying each common supply line to the plurality of compressor by cold-producing medium and oil, its In, compared with at least one non-dominant compressor described in the plurality of compressor, more oil returns To at least one leading compressor described；

Wherein, each in the plurality of compressor has on the bottom of its respective compressor housing Opening, each opening is constructed to allow for oil and flow to the oil sump of its respective compressor or from its respective pressure The oil sump of contracting machine flows out；

Wherein, each opening is connected to pipeline so that each described oil sump of the plurality of compressor Fluid communication；And

Wherein, each opening is positioned so as to the most described leading compressor and the most operates, described Oil all can compress by any non-dominant from described leading compressor distribution to the plurality of compressor Machine；

Described refrigeration system farther includes the oil eliminator being arranged on common supply line, described oil Separator is configured to compared with the described non-dominant compressor of the plurality of compressor to described leading compression The more oil of machine conveying.

No matter 11. refrigeration systems according to claim 10, wherein, the most just dominating compressor Operation, described leading compressor all by oil distribution to the plurality of compressor operating any Non-dominant compressor.

12. refrigeration systems according to claim 10, wherein, the plurality of compressor each There is the entrance supply line being connected to common supply line, and, at least one non-master pilot described The entrance supply line of any compressor in contracting machine has limiter and flows into its respective compression to reduce The oil of machine.

13. refrigeration systems according to claim 12, wherein, on described entrance supply line Described limiter structure is to produce the suction pressure reduced in the porch of its respective compressor.

14. refrigeration systems according to claim 10, wherein, each opening is in its respective pressure Position with approximately uniform horizontal position on contracting casing body.

15. refrigeration systems according to claim 14, wherein, each opening is located to work as In the plurality of compressor during all compressor operatings, oil flow to described non-master from described leading compressor Lead compressor, until each oil sump pressure of the plurality of compressor is approximately the same.

16. refrigeration systems according to claim 10, wherein, the multiple compressors being connected in parallel Including the multiple screw compressors being connected in parallel.

17. refrigeration systems according to claim 10, described refrigeration system farther includes structure For from each reception cold-producing medium of the plurality of compressor and the common discharge line of the flowing of oil.

18. refrigeration systems according to claim 10, wherein, except described at least one dominate Compressor, the rising of the oil sump pressure in the compressor not operated prevent oil from described at least one dominate Compressor distributes to the compressor not operated.

19. 1 kinds of refrigeration systems, comprising:

The multiple compressors being connected in parallel, the plurality of compressor includes at least one leading compressor, And each compressor of the plurality of compressor has compressor housing；

For by cold-producing medium and the supply line of oil supply extremely at least one leading compressor described, described Cold-producing medium and oil are from one or one of at least one leading compressor supply described to the plurality of compressor Individual above non-dominant compressor；

Wherein, each compressor has opening, Mei Gekai on the bottom of its respective compressor housing Outlet structure is to allow oil to flow to the oil sump of its respective compressor or from the oil sump stream of its respective compressor Go out；

Wherein, each opening is connected to pipeline so that each described oil of the plurality of compressor Pond is in fluid communication；And

Wherein, each opening is positioned so as to the most described leading compressor and the most operates, described Oil all can be from one or more non-master of described leading compressor distribution to the plurality of compressor Lead any compressor in compressor.

20. refrigeration systems according to claim 19, wherein, described leading compressor it Having head in compression case body, described head is connected to described supply line and is configured to arrange oil Enter the oil sump of described leading compressor.