CN103822419B - Refrigerating plant - Google Patents

Abstract

The present invention provides a kind of refrigerating plant, and its high-pressure side turns into critical pressure, can suitably maintain the circularly cooling dosage in refrigerant loop, so as to realize stable cooling performance.The refrigerating plant possesses：With refrigerant loop（1）The refrigerant amount regulating box of connection（100）And set up refrigerant amount regulating box（116）；Control device, the on high-tension side circulating refrigerant of refrigerant loop is recovered to each case by it, and the refrigerant for being recovered to each case is discharged to the middle intermediate pressure section or low-pressure side of refrigerant loop.Control device by refrigerant-recovery to each case, meanwhile, from these case discharging refrigerants, and, high side pressure and target high-pressure based on refrigerant loop adjust to each case and reclaim refrigerant and the degree from each case discharging refrigerant, thus, control the circularly cooling dosage in refrigerant loop.

Description

Refrigerating plant

Technical field

The present invention relates to form refrigerant loop and high-pressure side by compression set, gas cooler, throttling arrangement, evaporator As the refrigerating plant of supercritical pressure.

Background technology

At present, in this refrigerating plant, kind of refrigeration cycle is formed by compression set, gas cooler, throttling arrangement etc., by pressing The refrigerant of compression apparatus compression is radiated by gas cooler, after being depressurized by throttling arrangement, makes refrigerant by evaporator Evaporation, and cool down surrounding air using the evaporation of refrigerant now.In recent years, in this refrigerating plant, due to nature Environmental problem etc., it is impossible to reuse freon series coolant.Therefore, the substitute as freon refrigerant, developing makes It is used as the carbon dioxide of natural refrigerant.The known carbon dioxide coolant is the big refrigerant of height pressure difference, relative to facing The temperature of boundary's pressure is low, and by compression, the high-pressure side of refrigerant circulation is changed into supercriticality（For example, referring to patent document 1）.

Patent document 1：Japanese Patent Publication 7-18602 publications

Patent document 2：Japanese Unexamined Patent Publication 2011-133204 publications

Freon refrigerant as described above enters in receiving magazine after being come out from condenser, is temporarily detained herein, carries out Gas-liquid separation.The obtained liquid refrigerant that is separated is stranded in receiving magazine, for being freezed according to regulations such as extraneous gas temperature Dosage.On the other hand, in the case where becoming such as carbon dioxide of refrigerant as supercritical pressure using high-pressure side, if outside Portion's gas temperature declines, then carries out saturation circulation, therefore, refrigerant becomes gas-liquid mixture phase.On the other hand, if extraneous gas Temperature rises, such as rises to+25 DEG C~more than 30 DEG C, then refrigerant carries out supercritical steam cycle operating without liquefaction.Therefore, In the presence of that can not adjust circularly cooling dosage by receiving magazine, superfluous gaseous refrigerant causes high side pressure in refrigerant loop Abnormal the problem of rising.

Then, in order to avoid high side pressure rises extremely and is provided with high pressure cut-off device, still, the high pressure cut-off device In the case of high pressure cut-off setting value as defined in the high side pressure of refrigerant loop reaching, force to stop compression set to protect Protecting system, and if compression set stops, then the cooling that evaporator is carried out can also stop.

Then, following refrigerating plant is also developed：Refrigerant amount regulating box is connected in the high-pressure side of refrigerant loop, in height Press lateral pressure to rise, more than defined recovery threshold value in the case of, refrigerant is reclaimed from the high-pressure side of refrigerant loop, under pressure Drop, if less than defined discharge threshold value, to the middle intermediate pressure section discharging refrigerant of refrigerant loop, so as to prevent high side pressure It is abnormal to rise（For example, referring to patent document 2）.In the patent document 2, set from refrigerator unit into shop multiple old Row cabinet（Showcase unit）Refrigerant amount regulating box built in the refrigerator unit of the refrigerating plant of refrigerant is supplied, by the refrigerant Measure regulating box and the high-pressure side of refrigerant loop and middle intermediate pressure section connects, adjust circularly cooling dosage.

But the on high-tension side pressure of refrigerant loop is by the expansion valve of showcase side（Throttling arrangement）The influence of opening and closing and Change big.The more refrigerating plant of showcase connection quantity（In order to increase the horsepower of refrigerator unit, provided with multiple compressors （Compression set））, its variation is bigger.

Further, since the pipe arrangement of temperature Change caused by season or operating condition, link refrigerator unit and each showcase In liquid pipe outlet temperature and pressure change, therefore, the change of refrigerant amount in the liquid pipe is greatly.Further, since shop Scale is different, so as to link the length of the pipe arrangement of the refrigerator unit and each showcase（Construction piping length）Also it is different, therefore, Provide that appropriate refrigerant charge amount is also highly difficult.

Due to it is such the reasons why, if high side pressure exceed recovery threshold value, by refrigerant-recovery to refrigerant amount tune Case is saved, if less than discharge threshold value, in the control of discharging refrigerant, refrigerant is reclaimed and from refrigerant to refrigerant amount regulating box Amount regulating box discharging refrigerant is tempestuously carried out, and therefore, generates following problem：High side pressure can not restrain, moreover, adjoint The variation of circularly cooling dosage caused by recovery and discharge, refrigerating capacity produces variation, it is impossible to the cooling performance stablized.

The content of the invention

The present invention is founded to solve prior art problem, there is provided a kind of refrigerating plant, its high-pressure side, which turns into, to be faced Boundary's pressure, the circularly cooling dosage in refrigerant loop can be suitably maintained, so as to realize stable cooling performance.

The invention of first aspect provides a kind of refrigerating plant, by compression set, gas cooler, throttling arrangement, evaporator Refrigerant loop is formed, its high-pressure side turns into supercritical pressure, it is characterised in that possesses：Refrigerant amount regulating box, itself and refrigeration Agent loop connects；Control device, the on high-tension side circulating refrigerant of refrigerant loop is recovered to refrigerant amount regulating box by it, will The refrigerant for being recovered to the refrigerant amount regulating box is discharged to the middle intermediate pressure section or low-pressure side of refrigerant loop, and the control device will While refrigerant-recovery is to refrigerant amount regulating box, from the refrigerant amount regulating box discharging refrigerant, also, refrigerant is based on The high side pressure in loop and the desired value of the high side pressure adjust to refrigerant amount regulating box and reclaim refrigerant and from the system The degree of cryogen amount regulating box discharging refrigerant, thus, control the circularly cooling dosage in refrigerant loop.

The invention of second aspect provides a kind of refrigerating plant, by compression set, gas cooler, throttling arrangement, evaporator Refrigerant loop is formed, its high-pressure side turns into supercritical pressure, it is characterised in that possesses：Refrigerant amount regulating box, itself and refrigeration Agent loop connects；Control device, the on high-tension side circulating refrigerant of refrigerant loop is recovered to refrigerant amount regulating box by it, will The refrigerant of the refrigerant amount regulating box is recovered to discharge to the middle intermediate pressure section or low-pressure side of refrigerant loop, the control device with The rising of the on high-tension side pressure of refrigerant loop, changes the refrigerant-recovery speed to refrigerant amount regulating box.

The refrigerating plant of the invention of the third aspect is in the invention, it is characterised in that control device returns with refrigerant The rising of the high side pressure on road, make the refrigerant-recovery speed rising to refrigerant amount regulating box.

The refrigerating plant of the invention of fourth aspect is in the invention of second or third aspect, it is characterised in that control device While by refrigerant-recovery to refrigerant amount regulating box, adjusted based on the high side pressure of refrigerant loop from the refrigerant amount Case discharging refrigerant, also, the decline of the high side pressure with refrigerant loop, are slowly discharged from refrigerant amount regulating box Refrigerant.

The refrigerating plant of the invention of 5th aspect is in the invention, it is characterised in that possesses：First connected loop, its Connect the high-pressure side of refrigerant amount regulating box and refrigerant loop；Second connected loop, it is connected under refrigerant amount regulating box Portion and the middle intermediate pressure section or low-pressure side of refrigerant loop；First valve gear, it is arranged at the first connected loop, and has throttle power Energy；Second valve gear, it is arranged at the second connected loop, and control device is changed to refrigerant by the valve opening of the first valve gear The refrigerant-recovery speed of regulating box is measured, system is slowly discharged from refrigerant amount regulating box by the opening time of the second valve gear Cryogen.

The refrigerating plant of the invention of 6th aspect is in the invention, it is characterised in that possesses：Third connecting loop, its Connect the top of refrigerant amount regulating box and the middle intermediate pressure section of refrigerant loop；3rd valve gear, it is arranged at third connecting and returned Road, control device open the 3rd valve gear when by refrigerant-recovery to refrigerant amount regulating box.

The refrigerating plant of the invention of 7th aspect is in the invention of the second~the 6th aspect, it is characterised in that control device On the basis of the desired value of the high side pressure of refrigerant loop, control to refrigerant amount regulating box and reclaim refrigerant and from the system Cryogen amount regulating box discharging refrigerant.

The refrigerating plant of 8th invention is in each invention, it is characterised in that control device is based on extraneous gas temperature The evaporating temperature of refrigerant in degree and evaporator determines the desired value of the high side pressure of refrigerant loop.

The refrigerating plant of the invention of 9th aspect is in each invention, it is characterised in that uses dioxy as refrigerant Change carbon.

In the refrigerating plant that high-pressure side turns into supercritical pressure, if extraneous gas temperature exceedes defined temperature range, Then become to operate without liquefied supercritical steam cycle in refrigerant loop, therefore, as described in the prior art, it is impossible to pass through Receiving magazine adjusts liquid measure, still, according to the present invention, by being connected with refrigerant amount regulating box in refrigerant loop, will can make Superfluous refrigerant is recovered to refrigerant amount regulating box from high-pressure side in refrigerant circuit, and from refrigerant amount regulating box to refrigerant The middle intermediate pressure section or low-pressure side discharging refrigerant in loop suitably maintains the circularly cooling dosage in refrigerant loop.Thus, The unfavorable condition that the high-pressure side in refrigerant loop becomes abnormal pressure can be eliminated, can prevent from compressing caused by High Abnormal Pressure The overload running of device.

Particularly, in the invention of first aspect, control device is by by refrigerant-recovery to refrigerant amount regulating box To be discharged simultaneously, the desired value based on high side pressure adjusts recovery and the degree discharged to control circularly cooling dosage, because This, can prevent from reclaiming refrigerant and caused from refrigerant amount regulating box discharging refrigerant with to refrigerant amount regulating box The violent variation of circularly cooling dosage.

In addition, according to the invention of second aspect, control device is with the rising of the high side pressure of refrigerant loop, change To the refrigerant-recovery speed of refrigerant amount regulating box, thus, for example, by as described in the invention such as the third aspect, with high pressure The rising of lateral pressure make refrigerant-recovery speed rise, can prevent surplus refrigerant-recovery, similarly, can prevent with The violent variation of refrigerant and caused circularly cooling dosage is reclaimed to refrigerant amount regulating box.

In addition, as described in the invention of fourth aspect, by refrigerant-recovery to refrigerant amount regulating box, meanwhile, based on refrigeration The high side pressure in agent loop is from the refrigerant amount regulating box discharging refrigerant, moreover, the high pressure if over refrigerant loop The decline of lateral pressure, from refrigerant amount regulating box slowly discharging refrigerant, then equally it can also prevent with from refrigerant amount The violent variation of regulating box discharging refrigerant and caused circularly cooling dosage.

Thus, in accordance with the invention it is possible to suitably maintain refrigeration of the management high-pressure side as the refrigerating plant of critical pressure Circularly cooling dosage in agent loop, realize stable cooling performance.

In addition, as described in the invention in terms of the 5th, possess：First connected loop, it connects refrigerant amount regulating box and system The high-pressure side of refrigerant circuit；Second connected loop, it connects the middle nip of the bottom of refrigerant amount regulating box and refrigerant loop Domain or low-pressure side；First valve gear, it is arranged at the first connected loop, and has throttling function；Second valve gear, it is arranged at Second connected loop, control device change the refrigerant-recovery speed to refrigerant amount regulating box by the valve opening of the first valve gear Degree, by the opening time of the second valve gear from refrigerant amount regulating box slowly discharging refrigerant, so as to pass through first The opening time of the valve opening of valve gear and the second valve gear control exactly to refrigerant amount regulating box reclaim refrigerant and from The degree of refrigerant amount regulating box discharging refrigerant.

In addition, as described in the invention in terms of the 6th, set：Third connecting loop, it connects the upper of refrigerant amount regulating box Portion and the middle intermediate pressure section of refrigerant loop；3rd valve gear, it is arranged at third connecting loop, and control device returns by refrigerant When receiving refrigerant amount regulating box, the 3rd valve gear is opened, so as to make the pressure venting in refrigerant amount regulating box to case Outside.Thus, the pressure in refrigerant amount regulating box declines, refrigerant liquefaction and accumulation in the refrigerant amount regulating box, therefore, Can be successfully by the refrigerant-recovery in refrigerant loop to refrigerant amount regulating box.Now, due to adjusting refrigerant amount The top of case connects with the middle intermediate pressure section of refrigerant loop, therefore, the situation with the low-pressure side regional connectivity with refrigerant loop Difference, the reduction of cooling effectiveness caused by low-pressure lateral pressure rising can be avoided.

Particularly, as described in the invention in terms of the 7th, control device is by the desired value of the high side pressure of refrigerant loop As benchmark, control to refrigerant amount regulating box and reclaim refrigerant and from the refrigerant amount regulating box discharging refrigerant, so as to Enough degree based on high side pressure control recovery and discharging refrigerant, can reliably prevent high voltage protective and overload running. Thereby, it is possible to ensure the cooling performance of refrigerating plant, COP appropriateization can be realized.

In this case, as described in the invention of eighth aspect, if control device is based on extraneous gas temperature and evaporator In refrigerant evaporating temperature determine refrigerant loop high side pressure desired value, then it can be considered that due to extraneous gas Temperature becomes the state of the refrigerant of saturation circulation and supercritical steam cycle, and appropriate high pressure side pressure is realized based on evaporating temperature Power, can efficiently it be operated.

Also, as described in the invention in terms of the 9th, each invention is using the overcritical of carbon dioxide as refrigerant Refrigerant loop（Supercritical refrigeration cycle）In it is especially effective.

Brief description of the drawings

Fig. 1 is the refrigerant loop figure of the refrigerating plant of the present embodiment；

Fig. 2 is the block figure of the control device of Fig. 1 refrigerating plant；

Fig. 3 is the figure for the trend for representing the target high-pressure THP according to extraneous gas temperature and evaporating temperature decision；

Fig. 4 is to illustrate that Fig. 2 control device controls to reclaim refrigerant to refrigerant amount regulating box and adjust from refrigerant amount The figure of case discharging refrigerant.

Symbol description

R refrigerating plants

C control devices（Control unit）

1 refrigerant loop

3 refrigerator units

5 showcase units

7th, 9 refrigerant piping

11 compressors

Pressure goes out pipe arrangement in 36

38 intercoolers

44 separators

46 gas coolers

48 high-pressure pressure sensors（High-pressure detection means）

Pressure pressure sensor in 49（Middle pressure pressure detection means）

Unit 58 export side pressure sensor（Unit outlet side pressure-detecting device）

62 main throttling arrangements（Throttling arrangement）

63 evaporators

80 Intermediate Heat Exchangers

80A first flow path

80B second flow paths

83 auxiliary expansion valves（Aid in throttling arrangement）

100 refrigerant amount regulating boxs

101 first connected loops

102 electric expansion valves（The first valve gear with throttling function）

103 third connecting loops

104 magnetic valves（3rd valve gear）

105 second connected loops

106 magnetic valves（Second valve gear）

111 set up refrigerant amount adjusting means

116 set up refrigerant amount regulating box

117 electric expansion valves（First with throttling function sets up valve gear）

119 magnetic valves（3rd sets up valve gear）

122 magnetic valves（Second sets up valve gear）

126 first set up connection pipe arrangement（Form first and set up connected loop）

127 the 3rd set up connection pipe arrangement（Form the 3rd and set up connected loop）

128 second set up connection pipe arrangement（Form second and set up connected loop）

131 refrigerant encapsulation amount governor motions

Embodiment

Below, embodiments of the present invention are described with reference to.Fig. 1 is the refrigerating plant R of embodiment of the present invention system Refrigerant circuit figure.Refrigerating plant R in the present embodiment is made up of refrigerator unit 3 and multiple showcase units 5, these refrigeration machines Unit 3 and each showcase unit 5 pass through refrigerant piping 7（Liquid pipe）And refrigerant piping 9 links and forms defined refrigerant Loop 1.

The kind of refrigeration cycle uses on high-tension side refrigerant pressure（High-pressure）More than its critical pressure（It is overcritical） Carbon dioxide as refrigerant.The carbon dioxide coolant is to consider that the environmentally friendly of flammable and toxicity etc. freezes naturally Agent.In addition, the oil as lubricating oil uses such as mineral oil（Mineral oil）, alkylbenzene oil, ether oil, ester oil, PAG（Poly- alkylene Ethylene glycol）Etc. existing oil.

The refrigerator unit 3 of embodiment possesses two compressors 11 as compression set configured side by side.In this implementation In example, compressor 11 is internal medium-pressure type multiple compression rotary compressor, by cylindric closed container 12 and rotary compressor Structure portion is formed, and closed container 12 is made up of steel plate, and rotation/compression mechanism section is by configuring the electricity being accommodated in inside the closed container 12 Dynamic element（It is not shown）And the first rotary compression element driven by the electric element（First compressing member of rudimentary side）18 and Second rotary compression element（Second compressing member of advanced side）20 are formed.

First rotary compression element 18 from the low-pressure side of refrigerant loop 1 via refrigerant piping 9 to sucking compressor 11 Low pressure refrigerant be compressed, discharged after boosting to middle pressure, the second rotary compression element 20 will be by the first rotary compression element The middle compression refrigerant discharged after 18 compressions sucks again to be compressed, and is boosted to high pressure, is discharged to the high pressure of refrigerant loop 1 Side.Compressor 11 is the compressor of frequency conversion type, can be by changing the operating frequency of above-mentioned electric element, the rotation pressure of control first The rotating speed of the rotary compression element 20 of contracting element 18 and second.

Inhaled in the side of the closed container 12 of compressor 11 formed with the rudimentary side connected with the first rotary compression element 18 Entrance 22 and rudimentary side outlet 24 and the advanced side suction ports 26 connected with the second rotary compression element 20 and the discharge of advanced side Mouth 28.The rudimentary side suction ports 22 of each compressor 11 are connected to refrigerant ingress pipe 30, collaborate in each upstream side, with refrigeration Agent pipe arrangement 9 connects.

The low pressure of the low voltage section of the first rotary compression element 18 is sucked by rudimentary side suction ports 22（LP：Normal operation shape It is 2.6Mpa or so under state）Refrigerant gas boosts to middle pressure by first rotary compression element 18（MP：Normal operation It is down 5.5Mpa or so）Afterwards, it is discharged in closed container 12.Thus, middle pressure is become in closed container 12（MP）.

Moreover, the rudimentary side outlet 24 for each compressor 11 that the refrigerant gas of the middle pressure in closed container 12 is discharged It is connected to middle pressure and goes out pipe arrangement 36, collaborates in each downstream, be connected with one end of intercooler 38.The intercooler The refrigerant of 38 pairs of middle pressures from the discharge of the first rotary compression element 18 carries out air cooling, the other end connection of the intercooler 38 There is middle pressure suction line 40, after pressure suction line 40 is divided into two in this, be connected with the advanced side suction ports 26 of each compressor 11.

The middle pressure of the middle splenium of the second rotary compression element 20 is sucked by advanced side suction ports 26（MP）Refrigerant gas Body carries out the compression of the second level by second rotary compression element 20, becomes HTHP（HP：It is under normal operation 9Mpa or so supercritical pressure）Refrigerant gas.Moreover, be arranged at the second rotary compression element 20 of each compressor 11 The advanced side outlet 28 of hyperbaric chamber side be connected to high pressure discharge pipe arrangement 42, each downstream collaborate, via separator 44, The Intermediate Heat Exchanger 80 for the separation circulation that gas cooler 46, composition are explained in detail below is connected with refrigerant piping 7.

Gas cooler 46 cools down to the high pressure discharging refrigerant discharged from compressor 11, attached in gas cooler 46 It is near to be equipped with the gas cooler pressure fan 47 that air cooling is carried out to the gas cooler 46.In the present embodiment, gas cooling Device 46 is arranged side by side with above-mentioned intercooler 38 and the oil cooler 74 being explained in detail below, and they are disposed in same wind path 45.Should Wind path 45 is provided with the extraneous gas temperature sensor for the detection extraneous gas temperature that the refrigerator unit 3 arranges（Extraneous gas temperature Spend detection means）56.In addition, advanced side outlet 28,28 is provided with detection from the refrigerant of the second rotary compression element 20 discharge Discharge pressure（High side pressure HP）High-pressure pressure sensor（High-pressure detection means）48th, discharging refrigerant temperature is detected The discharge temperature sensor of degree（Discharge temperature detection means）50 etc..

On the other hand, each showcase unit 5 is respectively arranged in shop etc., be connected to side by side respectively refrigerant piping 7 and 9.Each showcase unit 5 has the cabinet side refrigerant piping 60 for linking refrigerant piping 7 and refrigerant piping 9, each cabinet side refrigeration It is connected with the main throttling arrangement 62 as throttling arrangement on agent pipe arrangement 60 in turn（Main expansion valve）With evaporator 63.Each evaporator 63 Circulating cold air (not shown) with being blown respectively to the evaporator 63 is abutted with pressure fan.Moreover, the institute as described above of refrigerant piping 9 State via refrigerant ingress pipe 30 with and the rudimentary side suction ports 22 that connect of the first rotary compression element 18 of each compressor 11 connect Connect.Thus, the refrigerant loop 1 of the refrigerating plant R in the present embodiment is formed.

Refrigerating plant R possesses the control device being made up of general microcomputer in electric box B（Control unit）C. Control device C as shown in Fig. 2 input side is connected with various sensors, meanwhile, outlet side is connected with various valve gears, compression The above-mentioned electric element 11M of machine 11（Compressor electric motor.With a representative）, gas cooler pressure fan 47 fan electromotor 47M etc..In addition, control device C is actual by the control device of the side of refrigerator unit 3 and the control device of the side of showcase unit 5 （It is not shown）, following control devices for setting up the side of refrigerant amount adjusting means 111（Also it is not shown）And the structure such as central control device Into, simplified herein, represented with control device C, its detailed content according to it is each control be set forth below.

（A）The adjustment control of circularly cooling dosage

Then, the adjustment control of the circularly cooling dosage of the refrigerant loop 1 of the refrigerating plant R in the present embodiment is illustrated. In the high-pressure side of the supercritical pressure as refrigerant loop 1, in the present embodiment, in the Intermediate Heat Exchanger of refrigerator unit 3 80 downstream is connected with refrigerant amount regulating box 100 via the first connected loop 101.The refrigerant amount regulating box 100 and pressure Contracting machine 11 and the grade of gas cooler 46 are built in refrigerator unit 3 together, and are connected with defined volume, the top of case 100 It is connected to the first connected loop 101.It is situated between in first connected loop 101 and is provided with electric expansion valve 102, it, which is used as, has throttling function The first valve gear.

In addition, the valve gear not limited to this with throttling function, in the first connected loop 101, as throttling arrangement example Such as can be by impedance value different multiple capillaries and magnetic valve（Valve gear）Deng composition.

Moreover, the middle pressure for connecting the internal upper part of case 100 and refrigerant loop 1 is connected with the refrigerant amount regulating box 100 The third connecting loop 103 in region.In the present embodiment, one as middle intermediate pressure section, the other end in third connecting loop 103 Connected with the middle pressure suction line 40 of the outlet side of the intercooler 38 of refrigerant loop 1.The third connecting loop 103, which is situated between, to be provided with Magnetic valve 104 as the 3rd valve gear.

The middle pressure of bottom and refrigerant loop 1 in the case 100 is connected in addition, being connected with the refrigerant amount regulating box 100 Second connected loop 105 in region.In the present embodiment, one as middle intermediate pressure section, the other end of the second connected loop 105 The first flow path 80A of the following Intermediate Heat Exchangers 80 connected with above-mentioned middle pressure suction line 40 entrance connects.In second company Logical loop 105, which is situated between, is provided with the magnetic valve 106 as the second valve gear and the capillary 107 as decompressor.

（A-0）Set up refrigerant amount adjusting means

In addition, the refrigerating plant R of embodiment is connected with setting up refrigerant amount adjusting means 111.This sets up refrigerant amount tune Regulating device 111 to refrigerant amount regulating box 100 according to refrigerating plant R scale in order to set up refrigerant amount regulating box 116 （This is also the refrigerant amount regulating box of the present invention）, and refrigerator unit 3 is selectively mounted at, set（Set up）In refrigeration machine Outside unit 3, it is removably connected with refrigerant loop 1.Do not scheme in this case, setting up refrigerant amount adjusting means 111 and possessing Have defined capacity inside the outer vanning shown sets up refrigerant amount regulating box 116, moreover, possessing：With setting up refrigerant amount Valve gear is set up in the top of regulating box 116 via the conduct with throttling function first（This is also the first valve gear of the present invention） Electric expansion valve 117 connect the first access hole（Service valve）118th, with set up the top of refrigerant amount regulating box 116 via Valve gear is set up as the 3rd（This is also the 3rd valve gear of the present invention）Magnetic valve 119 connect the 3rd access hole（Maintenance Valve）121st, valve gear is set up via as second with setting up the bottom of refrigerant amount regulating box 116（This is also the second of the present invention Valve gear）The second access hole that is connected with the capillary 123 as decompressor of magnetic valve 122（Service valve）124, these inspections Mouth 118,121,124 is repaiied from refrigerant amount adjusting means 111 is set up to expose in outside.

On the other hand, it is in the present embodiment refrigeration machine list in the high-pressure side of the supercritical pressure as refrigerant loop 1 The downstream connection of the Intermediate Heat Exchanger 80 of member 3 is provided with high pressure access hole（Service valve）112, with as in middle intermediate pressure section The third connecting loop 103 that pressure suction line 40 connects, which connects pre-installation, middle pressure access hole（Service valve）113.In addition, in conduct The refrigerant piping 9 of the low-pressure side of refrigerant loop 1, which connects pre-installation, low pressure access hole（Service valve）114, these access holes 112~114 also expose in outside from refrigerator unit 3.

Moreover, when this being set up into refrigerant amount adjusting means 111 being connected with refrigerant loop 1, set up by forming first Connected loop（This is also the first connected loop of the present invention）First set up connection pipe arrangement 126 by the first access hole 118 with it is high Pressure access hole 112 is removably connected and connected, and connected loop is set up by forming the 3rd（This is also the third connecting of the present invention Loop）The 3rd set up connection pipe arrangement 127 the 3rd access hole 121 be removably connected and connected with middle pressure access hole 113, it is logical Cross composition second and set up connected loop（This is also the second connected loop of the present invention）Second set up connection pipe arrangement 128 by second Access hole 124 is removably connected and connected with low pressure access hole 114.

Thus, connection pipe arrangement 126 and refrigerant loop 1 are set up in the top for setting up refrigerant amount regulating box 116 via first High-pressure side connection, electric expansion valve 117 is arranged at first and sets up in connected loop, sets up the upper of refrigerant amount regulating box 116 Portion also sets up connection pipe arrangement 127 via the 3rd and connected with the middle intermediate pressure section of refrigerant loop 1, and magnetic valve 119 is arranged at the 3rd increasing If in connected loop.In addition, connection pipe arrangement 128 and refrigerant are set up in the bottom for setting up refrigerant amount regulating box 116 via second The low-pressure side connection in loop 1, magnetic valve 122 are arranged at second and set up in connected loop.In addition, electric expansion valve 117 and first It is provided between access hole 118 and sets up high-pressure pressure sensor（Unit outlet side pressure-detecting device）120, in the first access hole In the state of 118 are connected with high pressure access hole 112, the detection high side pressure same with unit outlet side pressure sensor 58.

On the other hand, above-mentioned control device C is as shown in Fig. 2 input side is connected with unit outlet side pressure sensor（Unit Outlet side pressure-detecting device）58th, high-pressure pressure sensor is set up（Unit outlet side pressure-detecting device）120th, extraneous gas Temperature sensor 56, above-mentioned high-pressure pressure sensor 48 etc..The unit exports side pressure sensor 58 and refrigerant amount regulating box 100 the first connected loop 101 connects, and detection flows to the refrigerant pressure of the refrigerant piping 7 of showcase unit 5.Control dress The outlet side for putting C is connected with electric expansion valve（First valve gear）102nd, magnetic valve（3rd valve gear）104th, magnetic valve（Second Valve gear）106th, the electric element 11M of above-mentioned compressor 11, the fan electromotor 47M of the pressure fan 47 of gas cooler 46, main section Flow device 62.

In addition, control device C outlet side be also associated with being connected with refrigerant loop 1 set up refrigerant amount adjusting means 111 electric expansion valve（First sets up valve gear）117th, magnetic valve（3rd sets up valve gear）119th, magnetic valve（Second sets up Valve gear）122.In addition, the refrigeration in detection temperature and evaporator 63 of the control device C based on extraneous gas temperature sensor 56 The evaporating temperature of agent carries out gas cooler and controlled with the fan electromotor 47M of pressure fan 47 rotating speed.As described above, as control Device C also includes the control device for setting up the side of refrigerant amount adjusting means 111（It is not shown）Concept carry out the following description, but It is, in fact, in the state of refrigerator unit 3 has additional and sets up refrigerant amount adjusting means 111, it is above-mentioned to set up refrigerant amount The control device of the side of adjusting means 111 receives the detection of extraneous gas temperature sensor 56 from the control device C of refrigerator unit 3 The detection pressure of temperature and low-pressure sensor 32.Moreover, based on the data received and set up high-pressure pressure sensor 120 Detection pressure, set up the control device of the side of refrigerant amount adjusting means 111 by controlling electric expansion valve 117, magnetic valve 119 And 122, perform and following identical refrigerant-recoveries of refrigerant amount regulating box 100 and discharge.Thus, by by refrigerant-recovery To setting up in refrigerant amount regulating box 116, from the discharging refrigerant of refrigerant amount regulating box 116 is set up, thus, adjust and filled in refrigeration Put the refrigerant amount of circulation in R.

（A-1）Target high-pressure THP

Then, as described below, the high side pressure HP and the height that control device C is detected based on high-pressure pressure sensor 48 Press the desired value of lateral pressure（Target high-pressure：THP）To control to above-mentioned refrigerant amount regulating box 100 and set up refrigerant amount regulation Case 116 reclaims refrigerant and the discharging refrigerant from them, in this case, control device C is according to extraneous gas temperature TA and steaming The evaporating temperature TE for sending out the refrigerant in device 63 determines target high-pressure THP.

It is outside in the refrigerating plant R that the high-pressure side of refrigerant loop 1 turns into more than supercritical pressure such as the present embodiment Gas temperature TA carries out saturation circulation, in the temperature higher than+30 DEG C in a certain temperature, such as in the case of less than+30 DEG C Under, carry out supercritical steam cycle.When carrying out supercritical steam cycle, refrigerant does not liquefy, therefore, temperature and pressure be not only thus when Refrigerant amount in refrigerant loop 1 determines.Therefore, extraneous gas temperature TA is different, and target high-pressure THP is also different.

In the present embodiment, as one, in the extraneous gas temperature TA detected by extraneous gas temperature sensor 56 In lower limit temperature（Such as 0 DEG C）In the case of below, target high-pressure THP is constant, for defined lower limit THPL.It is in addition, outside Gas temperature TA is in the set point of temperature higher than 30 DEG C（Ceiling temperature）In the case of above, target high-pressure THP is constant, is defined Higher limit THPH.Also, extraneous gas temperature TA solves target as follows higher than lower limit temperature and less than in the case of ceiling temperature High pressure THP.

Determining as follows, i.e. extraneous gas temperature TA is than defined fiducial temperature, such as+30 DEG C low, The target high-pressure THP of high side pressure is more reduced, than defined fiducial temperature, such as+30 DEG C of height, it is high more to improve target Press THP.In addition, determine as follows, i.e. as described above, the conversion pressure detected by the low-pressure sensor 32 The evaporating temperature TE of refrigerant in obtained evaporator 63 is higher than defined fiducial temperature, more improves high side pressure Target high-pressure THP, it is lower than defined fiducial temperature, more reduce target high-pressure THP.Fig. 3 is represented by extraneous gas temperature The figure of the trend for the target high-pressure THP that TA and evaporating temperature TE is determined.

In addition, in the present embodiment, control device C is according to extraneous gas temperature TA and evaporating temperature TE and uses arithmetic expression Target high-pressure THP is calculated, still, is not limited to that, can also be based on prior by extraneous gas temperature TA and evaporating temperature TE Obtained tables of data obtains target high-pressure THP.

（A-2）Refrigerant-recovery/refrigerant discharge control

Below, illustrate control device C controls from refrigerant loop 1 to refrigerant amount regulating box 100 and set up refrigerant amount Regulating box 116 reclaims refrigerant and from them to the discharging refrigerant of refrigerant loop 1.In addition, control device C is in unit outlet side The high side pressure HP that pressure sensor 58 detects exceedes defined high voltage protective value（For example, 12MPa）In the case of, execution stops The high pressure cut-off action that only compressor 11 operates.As premise, illustrate the control that refrigerant-recovery and discharge is set forth below.

Control device C is based on above-mentioned target high-pressure THP and unit outlet side pressure sensor 58（As described previously for increasing If it is to set up high-pressure pressure sensor 120 for refrigerant amount retracting device 111）The high pressure side pressure of the refrigerant loop 1 of detection Power HP controls electric expansion valve（First valve gear）102 and electric expansion valve（First sets up valve gear）117th, magnetic valve（Second Valve gear）106 and magnetic valve（Second sets up valve gear）122nd, magnetic valve（3rd valve gear）104 and magnetic valve（3rd sets up Valve gear）119, thus, while by refrigerant-recovery to refrigerant amount regulating box 100 and refrigerant amount regulating box 116 is set up, one While the discharging refrigerant from them, also, the degree by adjusting refrigerant-recovery and refrigerant discharge is returned to adjust refrigerant Circularly cooling dosage in road 1.

Secondly, the refrigerant-recovery of control device C progress and the specific control of refrigerant discharge are illustrated using Fig. 4.In addition, In the following description, the refrigerant-recovery and discharge for only illustrating refrigerant amount regulating box 100 control（Electric expansion valve 102, The control of magnetic valve 106,104）, for setting up refrigerant amount regulating box 116, respectively with electric expansion valve 102, magnetic valve 106, The control of electric expansion valve 117, magnetic valve 122,119 is identical with the situation of refrigerant amount regulating box 100 corresponding to 104, omits Explanation.Connect it should be noted that setting up refrigerant amount regulating box 116 by the low-pressure side of magnetic valve 122 and refrigerant loop 1 Logical, discharging refrigerant is different from refrigerant amount regulating box 100 on this point.

Fig. 4 represent along with high side pressure HP change electric expansion valve 102 valve opening control and magnetic valve 106, The differentiation of 104 open and close controlling.Assuming that it is now arranged in the high pressure for the refrigerant loop 1 that unit outlet side pressure sensor 58 detects The Fig. 4 of lateral pressure HP near the target high-pressure THP determined as described above UP2 states, control device C is by electric expansion valve 102（It is electric expansion valve 117 in the case of setting up refrigerant amount regulating box 116.Similarly hereinafter）Valve opening be set to full-shut position, Open magnetic valve 106（It is magnetic valve 119 in the case of setting up refrigerant amount regulating box 116.Similarly hereinafter）, close magnetic valve 104 （It is magnetic valve 122 in the case of setting up refrigerant amount regulating box 116.Similarly hereinafter）.Under the state, refrigerant amount regulating box 100 （And set up refrigerant amount regulating box 116.Similarly hereinafter）Do not connected with high-pressure side inside, top does not also connect with middle intermediate pressure section, only under Portion and middle intermediate pressure section（It is low-pressure side in the case of setting up refrigerant amount regulating box 116）Connection.Therefore, refrigerant amount regulating box Refrigerant in 100 is all to the middle intermediate pressure section of refrigerant loop 1（It is low pressure in the case of setting up refrigerant amount regulating box 116 Side.Similarly hereinafter）Discharge, become empty state in refrigerant amount regulating box 100, it is therefore prevented that so-called fluid-tight.

Control device C is every defined sampling time T1（For example, 200ms etc.）Read in unit outlet pressure sensor 58 （In the case of setting up refrigerant amount regulating box 116, to set up high-pressure pressure sensor 120.Similarly hereinafter）The high side pressure of detection HP, compared with target high-pressure THP, the transition of the solid arrow of process decision chart 4.That is, high side pressure HP is from Fig. 4 UP2 states Rise, if being higher than such as target high-pressure THP+1.0（MPa）（Target high-pressure THP+1.0 ＜ high side pressures HP）, then control device C is transitioned into Fig. 4 UP3 states.Under the UP3 states, control device C closes magnetic valve 106, by the valve of electric expansion valve 102 Aperture is from full-shut position（Zero step-length（0step））Open regulation step-length（step）S（For example, 100 step-lengths etc.）.In addition, open electricity Magnet valve 104.

Thus, the high-temperature high-pressure refrigerant discharged from the advanced side outlet 28 of compressor 11 passes through separator 44, passes through After gas cooler 46, Intermediate Heat Exchanger 80 cool down, a part is via the first connection provided with the electric expansion valve 102 opened that is situated between Loop 101（In the case of setting up refrigerant amount regulating box 116, connection pipe arrangement 126 is set up for first.Similarly hereinafter）It is flowed into refrigerant Measure in regulating box 100.

In addition, high side pressure HP from Fig. 4 UP3 states are further up, if being higher than such as target high-pressure THP+1.3 （MPa）（Target high-pressure THP+1.3 ＜ high side pressures HP）, then control device C be transitioned into Fig. 4 UP4 states.In the UP4 shapes Under state, control device C closes magnetic valve 106, the step-length S by the valve opening of electric expansion valve 102 from UP3（100 step-lengths）Enter one Step opens regulation step-length S, and valve opening is correspondingly expanded to from full-shut position and opens step-length 2S（200 step-lengths）State.It is in addition, electric Magnet valve 104 is still opened.Thus, refrigerant amount regulating box 100 is flowed into from the first connected loop 101 via electric expansion valve 102 Refrigerant recovery speed improve.

In addition, high side pressure HP from Fig. 4 UP4 states are further up, if being higher than such as target high-pressure THP+1.6 （MPa）（Target high-pressure THP+1.6 ＜ high side pressures HP）, then control device C be transitioned into Fig. 4 UP5 states.In the UP5 shapes Under state, control device C closes magnetic valve 106, the step-length 2S by the valve opening of electric expansion valve 102 from UP4（200 step-lengths）Enter one Step opens regulation step-length S, and valve opening is correspondingly expanded to from full-shut position and opens step-length 3S（300 step-lengths）State.It is in addition, electric Magnet valve 104 is still opened.Thus, refrigerant amount regulating box 100 is flowed into from the first connected loop 101 via electric expansion valve 102 The recovery speed of refrigerant further improve.

During UP2 to the UP5, magnetic valve 104 is opened, thus, it is possible to via connection refrigerant amount regulating box 100 The third connecting loop 103 of the middle intermediate pressure section of top and refrigerant loop 1（In the case of setting up refrigerant amount regulating box 116, it is 3rd sets up connection pipe arrangement 127.Similarly hereinafter）Pressure in refrigerant amount regulating box 100 is discharged into outside case respectively.Therefore, even if In the feelings for the not liquefied supercritical steam cycle operating of refrigerant that situation that outside gas temperature uprises etc. is carried out in refrigerant loop 1 Under condition, the pressure in refrigerant amount regulating box 100 declines, the refrigerant liquefaction flowed into the refrigerant amount regulating box 100, accumulation In refrigerant amount regulating box 100.Dropped to below supercritical pressure, made by the pressure in refrigerant amount regulating box 100 Cryogen becomes zone of saturation from gas zones, can ensure liquid level.

Thereby, it is possible to quickly and efficiently by the refrigerant-recovery in refrigerant loop 1 to refrigerant amount regulating box 100 （And set up refrigerant amount regulating box 116）.Therefore, it is possible to eliminate the high-pressure side in refrigerant loop 1 because surplus refrigerant and Become the unfavorable condition of abnormal pressure, the overload running of compressor 11 caused by High Abnormal Pressure can be prevented.

So, control device C expands the valve opening of electric expansion valve 102 as high side pressure HP rises, and improves to system The refrigerant-recovery speed of cryogen amount regulating box 100.

Then, by so by refrigerant-recovery to refrigerant amount regulating box 100, since the UP5 states, unit outlet The high side pressure HP that pressure sensor 58 detects declines, and high side pressure HP drops to such as target high-pressure THP+0.6 （MPa）In the case of below, control device C is transitioned into Fig. 4 DN4 states.In addition, control device C is every more than above-mentioned sampling Time T1 defined sampling time T2（For example, 3s etc.）Read in the high side pressure of the detection of unit outlet pressure sensor 58 HP, compared with target high-pressure THP, the transition of the dotted arrow of process decision chart 4.

Under the DN4 states, the valve opening of electric expansion valve 102 is narrowed down to step-length S/2 by control device C（From fully closed shape State opens the state of 50 step-lengths.Refrigerant-recovery speed is minimum.）, meanwhile, magnetic valve 104 is closed.In addition, magnetic valve 106 is beaten Open stipulated time t1（For example, 10s）After close.Thus, while via electric expansion valve 102 into refrigerant amount regulating box 100 Refrigerant is reclaimed, while being discharged via magnetic valve 104 out of refrigerant amount regulating box 100 to the middle intermediate pressure section of refrigerant loop 1 The refrigerant of ormal weight.

The discharge of the refrigerant also makes high side pressure HP still continue to reduce, and is being down to such as target high-pressure THP+ 1.2（MPa）Following situation（High side pressure HP≤target high-pressure+1.2）Under, control device C is transitioned into Fig. 4 DN3 shapes State.Under the DN3 states, the valve opening of electric expansion valve 102 is similarly narrowed down to step-length S/2, magnetic valve by control device C 104 also still close.In addition, closed after magnetic valve 106 is opened into stipulated time t1 again.Thus, while via electronic swollen Swollen valve 102 reclaims refrigerant into refrigerant amount regulating box 100, while via magnetic valve 104 out of refrigerant amount regulating box 100 The refrigerant of ormal weight is then exhausted to the middle intermediate pressure section of refrigerant loop 1.

In addition, the discharge of the refrigerant also makes high side pressure HP still continue to reduce, such as target high-pressure is being down to THP+0.9（MPa）Following situation（High side pressure HP≤target high-pressure+0.9）Under, control device C is transitioned into Fig. 4's DN2 states.Under the DN2 states, the valve opening of electric expansion valve 102 is similarly narrowed down to step-length S/2 by control device C, Magnetic valve 104 is also still closed.In addition, closed after magnetic valve 106 is opened into stipulated time t1 again.Thus, while via Electric expansion valve 102 reclaims refrigerant into refrigerant amount regulating box 100, while being adjusted via magnetic valve 104 from refrigerant amount The refrigerant of ormal weight is then exhausted from case 100 to the middle intermediate pressure section of refrigerant loop 1.

Moreover, the discharge of the refrigerant also makes high side pressure HP still continue to reduce, such as target high-pressure is being down to Below THP situation（High side pressure≤target high-pressure）Under, control device C is transitioned into Fig. 4 DN1 states.In the DN1 states Under, control device C makes electric expansion valve 102 fully closed, and magnetic valve 104 is also still closed.In addition, magnetic valve 106 is in open shape State, so as to return to and above-mentioned UP2 states identical state.

So, control device C with high side pressure HP reduce, from refrigerant amount regulating box 100 to low-pressure side slowly Discharging refrigerant, i.e., by by magnetic valve 106 it is most short every sampling time T2 open stipulated time t1 come to low-pressure side slowly Discharging refrigerant.

In addition, since Fig. 4 DN1 states, high side pressure HP switchs to rise, in the situation higher than target high-pressure THP （High side pressure HP ＞ target high-pressures THP）Under, control device C is transitioned into Fig. 4 UP2 states, and the state of each valve is identical.Separately Outside, since Fig. 4 DN2 states, the discharge of refrigerant makes high side pressure HP switch to rise, higher than such as target high-pressure THP+1.0（MPa）Situation（High side pressure HP ＞ target high-pressures THP+1.0）Under, control device C is transitioned into Fig. 4 UP3 State.That is, under UP3 states, control device C closes magnetic valve 106, by the valve opening of electric expansion valve 102 from full-shut position （Zero step-length）Open step-length S（100 step-lengths）, open magnetic valve 104.Thus, refrigerant-recovery speed improves.

In addition, since Fig. 4 DN3 states, the discharge of refrigerant makes high side pressure HP switch to rise, higher than for example Target high-pressure THP+1.3（MPa）Situation（High side pressure HP ＞ target high-pressures THP+1.3）Under, control device C is transitioned into Fig. 4 UP4 states.That is, under UP4 states, control device C close magnetic valve 106, by the valve opening of electric expansion valve 102 from Full-shut position（Zero step-length）Open step-length 2S（200 step-lengths）, open magnetic valve 104.Thus, refrigerant-recovery speed further carries It is high.

In addition, since Fig. 4 DN3 states, the discharge of refrigerant makes high side pressure HP switch to rise, higher than for example Target high-pressure THP+1.6（MPa）Situation（High side pressure HP ＞ target high-pressures THP+1.6）Under, control device C is transitioned into Fig. 4 UP5 states.That is, under UP5 states, control device C close magnetic valve 106, by the valve opening of electric expansion valve 102 from Full-shut position（Zero step-length）Open step-length 3S（300 step-lengths）, open magnetic valve 104.Thus, refrigerant-recovery speed further carries It is high.

On the contrary, since Fig. 4 UP4 states, the recovery of refrigerant makes high side pressure HP switch to decline, and is dropping to example Such as target high-pressure THP+0.3（MPa）Following situation（High side pressure HP≤target high-pressure THP+0.3）Under, control device C It is transitioned into Fig. 4 DN3 states.That is, under DN3 states, the valve opening of electric expansion valve 102 is narrowed down to step-length by control device C S/2, magnetic valve 104 is closed, is closed after magnetic valve 106 is opened into stipulated time t1.Thus, while via electric expansion valve 102 reclaim refrigerant into refrigerant amount regulating box 100, while interior to system from refrigerant amount regulating box 100 via magnetic valve 104 The refrigerant of the middle intermediate pressure section discharge ormal weight of refrigerant circuit 1.

In addition, since Fig. 4 UP3 states, the recovery of refrigerant makes high side pressure HP switch to decline, and is dropping to example Such as below target high-pressure THP situation（High side pressure HP≤target high-pressure THP）Under, control device C is transitioned into Fig. 4 DN2 State.That is, under DN2 states, the valve opening of electric expansion valve 102 is narrowed down to step-length S/2 by control device C, closes magnetic valve 104, closed after magnetic valve 106 is opened into stipulated time t1.Thus, while being adjusted via electric expansion valve 102 to refrigerant amount Save recovery refrigerant in case 100, while via magnetic valve 104 out of refrigerant amount regulating box 100 to the middle pressure of refrigerant loop 1 Discharge the refrigerant of ormal weight in region.

In addition, under such as Fig. 4 DN4 states, it is stable higher than target high-pressure THP+1.2 in high side pressure HP （MPa）And in target high-pressure THP+1.6（MPa）In the case of in the state of below, control device C maintains DN4 states.That is, it is high Pressure lateral pressure HP is maintained above in the state of target high-pressure THP, accordingly, it is capable to ensure refrigerating plant R cooling performance.

So, refrigerant loop 1 is connected with refrigerant amount regulating box 100 and sets up refrigerating plant 116, so as to make Superfluous refrigerant from the lateral refrigerant amount regulating box 100 of high pressure and is set up refrigerant amount regulating box 116 and returned in refrigerant circuit 1 Receive, in addition, from refrigerant amount regulating box 100 to the middle intermediate pressure section of refrigerant loop 1, from set up refrigerant amount regulating box 116 to Low-pressure side discharging refrigerant, so as to suitably maintain the circularly cooling dosage in refrigerant loop 1.Thereby, it is possible to eliminate refrigeration High-pressure side in agent loop 1 becomes the unfavorable condition of abnormal pressure, can prevent the overload of compressor 11 caused by High Abnormal Pressure Operating.

Particularly, control device C while to refrigerant amount regulating box 100 and set up refrigerant amount regulating box 116 recovery system Cryogen, while being discharged, circularly cooling dosage is controlled by adjusting the degree of recovery and discharge based on target high-pressure THP, Therefore, it is possible to prevent with to refrigerant amount regulating box 100 and set up refrigerant amount regulating box 116 reclaim refrigerant and from they The violent variation of middle discharging refrigerant and caused circularly cooling dosage.

In addition, control device C rises with the high side pressure HP of refrigerant loop 1, change to refrigerant amount regulating box 100 and the refrigerant-recovery speed of refrigerant amount regulating box 116 is set up, meanwhile, as high side pressure HP rises, improve refrigeration Speed is reclaimed in agent, therefore, it is possible to prevent the refrigerant-recovery of surplus, can effectively prevent with to refrigerant amount regulating box 100 and set up the violent variation that refrigerant amount regulating box 116 reclaims refrigerant and caused circularly cooling dosage.

And then while to refrigerant amount regulating box 100 and set up the recovery refrigerant of refrigerant amount regulating box 116, one side base From refrigerant amount regulating box 100 and the discharge refrigeration of refrigerant amount regulating box 116 is set up in the high side pressure HP of refrigerant loop 1 Agent, also, decline with the high side pressure HP of refrigerant loop 1, from refrigerant amount regulating box 100 and set up refrigerant amount tune The slowly discharging refrigerant of case 116 is saved, therefore, it is possible to effectively prevent with from refrigerant amount regulating box 100 and setting up refrigeration The violent variation of the discharging refrigerant of dosage regulating box 116 and caused circularly cooling dosage.

In refrigerant loop 1 thereby, it is possible to suitably maintain to manage the refrigerating plant R that high-pressure side becomes critical pressure Circularly cooling dosage, realize stable cooling performance.

In addition, control device C changed by the valve opening of electric expansion valve 102,117 to refrigerant amount regulating box 100 and The refrigerant-recovery speed of refrigerant amount regulating box 116 is set up, is adjusted using the opening time of magnetic valve 106,122 from refrigerant amount Save case 100 and set up the slowly discharging refrigerant of refrigerant amount regulating box 116, therefore, it is possible to pass through electric expansion valve 102,117 Valve opening and the opening time of magnetic valve 106,122 control exactly to refrigerant amount regulating box 100 and set up refrigerant amount Regulating box 116 reclaim refrigerant and from them discharging refrigerant degree.

In addition, control device C by refrigerant-recovery to refrigerant amount regulating box 100 and is setting up refrigerant amount regulating box When 116, magnetic valve 104,119 is opened, therefore, it is possible to by refrigerant amount regulating box 100 and set up in refrigerant amount regulating box 116 Pressure be discharged into outside case, can successfully by the refrigerant-recovery in refrigerant loop 1 to refrigerant amount regulating box 100 and increase If refrigerant amount regulating box 116.Now, make refrigerant amount regulating box 100 and set up top and the system of refrigerant amount regulating box 116 The middle intermediate pressure section connection of refrigerant circuit 1, it is therefore, different from the situation of the low-pressure side regional connectivity with refrigerant loop 1, it can keep away Exempt from the reduction of cooling effectiveness caused by low-pressure lateral pressure rising.

In addition, control device C is controlled on the basis of the target high-pressure THP of refrigerant loop 1 to refrigerant amount regulating box 100 And set up refrigerant amount regulating box 116 and reclaim refrigerant and the discharging refrigerant from them, therefore, it is possible to based on high side pressure HP controls refrigerant-recovery and the degree of discharge, can reliably prevent high voltage protective and overload running.Thereby, it is possible to ensure to make Device for cooling R cooling performance, COP appropriateization can be realized.

In this case, as described above, the steaming of refrigerants of the control device C in extraneous gas temperature and evaporator 63 Send out temperature and determine target high-pressure THP, it can be considered that because extraneous gas temperature becomes the refrigeration of saturation circulation and supercritical steam cycle The state of agent, and appropriate high side pressure is realized according to evaporating temperature, can efficiently it be operated.

In addition, in this case, compressor 11（Compression set）Using being assembled with first, second pressure in closed container 12 The two-stage compression rotary compressor of contracting element 18,20 and electric element, in addition or two single-stages can be passed through Therefrom splenium takes out refrigerant and the device of the mode imported for rotary compressor or the compressor of other forms.

（B）Separation circulation

Then, the refrigerating plant R of embodiment separation circulation is illustrated.In refrigerating plant R in embodiment, by each compressor 11 above-mentioned first rotary compression element（Rudimentary side 18）, intercooler 38, as the interflow dress for making two fluid streams interflow That puts collaborates device 81, above-mentioned second rotary compression element of each compressor 11（Advanced side）20th, separator 44, gas cooler 46th, current divider 82, auxiliary throttling arrangement（Auxiliary expansion valve）83rd, Intermediate Heat Exchanger 80, main throttling arrangement（Main expansion valve）62nd, steam Send out device 63 and form kind of refrigeration cycle.

Current divider 82 is the part flow arrangement that the refrigerant come out from gas cooler 46 is divided into two tributaries.That is, this reality The current divider 82 for applying example is formed as follows：The refrigerant come out from gas cooler 46 is divided into the first cold-producing medium stream and the second refrigeration Agent stream, the first cold-producing medium stream is flowed through subsidiary loop, second refrigerant stream is flowed through major loop.

Major loop in Fig. 1 refers to by the first rotary compression element 18 of compressor 11, intercooler 38, interflow device 81st, the second rotary compression element 20, gas cooler 46, current divider 82, the second flow path 80B of Intermediate Heat Exchanger 80, main throttling Device 62, the annular refrigerant loop that evaporator 63 is formed, subsidiary loop refer to from current divider 82 successively by auxiliary throttling Device 83, Intermediate Heat Exchanger 80 first flow path 80A after reach interflow device 81 loop.Under magnetic valve 106, capillary 107 Above-mentioned second connected loop 105 and the first flow path 80A entrances in auxiliary throttling arrangement 83 downstream for swimming side collaborate.

Auxiliary throttling arrangement 83 flows into the first refrigerant for flowing into subsidiary loop obtained by the shunting of above-mentioned current divider 82 Row decompression.Intermediate Heat Exchanger 80 is to the first cold-producing medium stream and second via the subsidiary loop after being depressurized by auxiliary throttling arrangement 83 The refrigerant that connected loop 105 is discharged from the bottom of refrigerant amount regulating box 100（Below, they are referred to as the first refrigerant Stream）With the heat exchanger for being split device 82 and shunting obtained second refrigerant stream and being exchanged heat.The Intermediate Heat Exchanger 80 is can exchange heat Relation be provided with the second flow path 80B that flows through of second refrigerant stream and first flow path 80A that above-mentioned first cold-producing medium stream flows through, lead to The second flow path 80B of the Intermediate Heat Exchanger 80 is crossed, thus, the first refrigeration that second refrigerant stream is circulated in first flow path 80A Agent stream cools down, therefore, it is possible to reduce the specific enthalpy in evaporator 63.

Above-mentioned control device C is as shown in Fig. 2 input side is connected with discharge temperature sensor（Discharge temperature detection means） 50th, said units outlet side pressure sensor（Unit outlet side pressure-detecting device）58th, middle pressure pressure sensor（Middle pressure pressure Detection means）49th, low-pressure sensor（Suction pressure detection means）32nd, gas cooler exit temperature sensor（Gas Cooler outlet temperature-detecting device）52nd, unit outlet temperature sensor（Unit outlet temperature detection means）54th, unit entrance Temperature sensor（Inlet temperature detection means）34.

Discharge temperature sensor 50 is arranged at the advanced side outlet 28 of each compressor 11, detects from the second rotary compression member The discharge temperature for the refrigerant that part 20 is discharged.Unit outlet side pressure sensor 58 is said units outlet side pressure sensor. Low-pressure sensor 32 is located at the low-pressure side of refrigerant loop 1, is each downstream of evaporator 63 in the present embodiment, sets In the refrigerant piping 9 that the rudimentary side suction ports 22 with compressor 11 are connected, detection flows to the refrigeration of the refrigerant ingress pipe 30 The suction pressure of agent.Middle pressure pressure sensor 49 detects the middle intermediate pressure section of refrigerant loop 1, in the present embodiment, for detection electricity The pressure in the third connecting loop 103 in the downstream of magnet valve 104.

Gas cooler exit temperature sensor 52 is arranged at the outlet side of gas cooler 46, detects from the gas cooling The temperature for the refrigerant that device 46 comes out（GCT）.Unit outlet temperature sensor 54 is arranged at the centre being connected with refrigerant piping 7 The outlet side of heat exchanger 80, detection unit outlet temperature（LT）.Unit inlet temperature sensor 34 is arranged at and compressor 11 The refrigerant piping 9 that rudimentary side suction ports 22 connect, detection flow to the inlet temperature of the refrigerant of the refrigerant ingress pipe 30.And And control device C outlet side is connected with the auxiliary throttling arrangement 83 for forming separation circulation.The auxiliary throttling arrangement 83 is also logical Cross the electric expansion valve of step motor control aperture.

Below, the aperture control of auxiliary throttling arrangement 83 is described in detail.Aid in operation start of the throttling arrangement 83 in compressor 11 Moment is defined initial valve opening.Afterwards, control device C is based on following first controlled quentity controlled variable, the second controlled quentity controlled variable, the 3rd controlled quentity controlled variable Determine the operational ton of the valve opening of increase auxiliary throttling arrangement 83.

（B-1）Aid in the valve opening increase control of throttling arrangement

First controlled quentity controlled variable（DTcont）Obtained according to the discharging refrigerant temperature DT of compressor 11.In control device C judgements Whether the temperature DT for stating the detection of discharge temperature sensor 50 is higher than setting DT0, in discharging refrigerant temperature DT higher than regulation It is the controlled quentity controlled variable of the direction effect for the aperture that throttling arrangement 83 is aided in increase in the case of value DT0.Setting DT0 is ratio The limiting temperature of the appropriate operating of compressor 11 can be realized（It it is+100 DEG C as one）Slightly lower temperature（As one, For+95 DEG C）, in the case where temperature rises, controlled as follows：By increasing the aperture of auxiliary throttling arrangement 83, to suppress The temperature of the compressor 11 rises, and compressor 11 is not up to limiting temperature.

Second controlled quentity controlled variable（MPcont）It is the refrigerant amount for the subsidiary loop that regulation flows through separation circulation come pressure in realizing （MP）The controlled quentity controlled variable suitably changed.In the present embodiment, in judgement pressure pressure sensor 49 detect refrigerant loop 1 middle nip Whether the pressure MP in domain is higher than the high side pressure HP of refrigerant loop 1 that is detected by unit outlet side pressure sensor 58 and low The low-pressure lateral pressure LP for the refrigerant loop 1 that pressure pressure sensor 32 detects is calculated（Solve）Appropriate middle pressure value, at this In the case that the pressure MP of middle intermediate pressure section is less than appropriate middle pressure value, it is set to aid in the direction of the aperture of throttling arrangement 83 to increase Effect.

In addition, pressure value can be multiplied with low-pressure lateral pressure LP averagely by the high side pressure HP that detects to count in appropriate Calculate, in addition to this it is possible to appropriate middle pressure value is experimentally obtained by high side pressure HP and low-pressure lateral pressure LP in advance, by The tables of data that makes accordingly and determine.

In addition, in the present embodiment, by by the appropriate middle pressure value of high side pressure HP and low-pressure lateral pressure LP solutions and The pressure MP of middle intermediate pressure section is compared to determine the second controlled quentity controlled variable（MPcont）, still, it is not limited to that, for example, also may be used With with the following method.That is, the pressure MP of the middle intermediate pressure section of the refrigerant loop 1 detected by middle pressure pressure sensor 49 and by low The low-pressure lateral pressure LP for the refrigerant loop 1 that pressure pressure sensor 32 detects solves overcompression decision content MPO, judges the overcompression Whether decision content MPO exports the high side pressure HP for the refrigerant loop 1 that side pressure sensor 58 detects less than unit, in overvoltage In the case that contracting decision content MPO is less than high side pressure HP, it is set to aid in the direction of the aperture of throttling arrangement 83 to act on to increase. By making second controlled quentity controlled variable be reflected in the aperture control of auxiliary throttling arrangement 83, high side pressure can be suitably kept HP, the pressure MP of middle intermediate pressure section, low-pressure lateral pressure LP pressure differential, the stabilisation of kind of refrigeration cycle operating can be realized.

3rd controlled quentity controlled variable（SPcont）It is to realize the refrigerant temperature LT come out from the second flow path of Intermediate Heat Exchanger 80 The controlled quentity controlled variable suitably changed.In the present embodiment, control device C judges the process that gas cooler exit temperature sensor 52 detects The temperature GCT of refrigerant after gas cooler 46 detects after 80s by Intermediate Heat Exchanger with unit outlet temperature sensor 54 Second refrigerant stream temperature LT difference（GCT-LT）Whether it is less than setting SP, in the case of less than setting SP, makes It aids in the direction of the aperture of throttling arrangement 83 to act on to increase.

Here, setting setting SP in the case where high side pressure HP is in the supercritical range of the refrigerant and is in It is different in the case of zone of saturation.In the present embodiment, high side pressure HP is to be in saturation region in supercritical range Domain is that the extraneous gas temperature detected according to extraneous gas temperature sensor 56 is judged, in the high feelings of the extraneous gas temperature Under condition, for example, more than+31 DEG C, it is judged as being in supercritical range, in the case where outside gas temperature is low, for example, insufficient + 31 DEG C, it is judged as being in zone of saturation.Also, in the case where being judged as being in supercritical range, setting setting SP is carried Height, in the case where being judged as being in zone of saturation, setting setting SP is reduced.In the present embodiment, in supercritical range, Setting SP is set to 35 DEG C, in zone of saturation, is set to 20 DEG C.

Control device C is by obtain as described above three controlled quentity controlled variables, i.e. the first controlled quentity controlled variable（DTcont）, the second controlled quentity controlled variable （MPcont）, the 3rd controlled quentity controlled variable（SPcont）It is added, determines the operational ton of the valve opening of auxiliary throttling arrangement 83, increase valve accordingly Aperture.

（B-2）The valve opening of throttling arrangement is aided in reduce control

In addition, control device C is by the temperature LT by Intermediate Heat Exchanger second refrigerant stream after 80s or from compressor The 11 discharging refrigerant temperature DT and temperature GCT of the refrigerant after gas cooler 46 difference determines to reduce auxiliary throttling The operational ton of the valve opening of device 83.

That is, second system after 80s by Intermediate Heat Exchanger that control device C judging units outlet temperature sensor 54 detects Whether the temperature LT of cryogen stream is less than setting.In the present embodiment, as one, the setting is set to 0 DEG C.Thus, in list In the case that first outlet temperature is below 0 DEG C, is operated, can be eliminated to the direction for reducing the aperture for aiding in throttling arrangement 83 In the unfavorable condition that the second refrigerant stream that Intermediate Heat Exchanger 80 cools down is cooled excessively.

In addition, control device C judges that the temperature DT that discharge temperature sensor 50 detects passes with gas cooler exit temperature The temperature GCT for the refrigerant after gas cooler 46 that sensor 52 detects difference（DT-GCT）Whether setting is less than TDT, in the case of less than setting TDT, it is set to be acted on to the direction for reducing the aperture for aiding in throttling arrangement 83.

Here, setting TDT is in the case where high side pressure HP is in the supercritical range of the refrigerant and is in It is different in the case of zone of saturation.In the present embodiment, it is identical with solving the situation of above-mentioned 3rd controlled quentity controlled variable, high side pressure HP It is to be in zone of saturation in supercritical range according to extraneous gas temperature to be judged.Also, it is being judged as in super In the case of critical zone, setting setting TDT is reduced, and in the case where being judged as being in zone of saturation, sets setting TDT Improve.In the present embodiment, in supercritical range, it is specified that value TDT is set to 10 DEG C, in zone of saturation, 35 DEG C are set to.

Control device C is in the temperature LT by Intermediate Heat Exchanger second refrigerant stream after 80s in setting（0℃）Below Situation or discharging refrigerant temperature DT from compressor 11 with the temperature GCT's of the refrigerant after gas cooler 46 In the case that difference is less than setting TDT, the operational ton of the valve opening of auxiliary throttling arrangement 83 is determined, no matter above-mentioned valve opening increases How is control, all reduces valve opening accordingly.

In refrigerating plant R in the present embodiment for possessing separation circulation as described above, it can will pass through gas cooling Refrigerant after device 46 radiates shunts, using by the refrigeration of the first cold-producing medium stream cooling second of the puffing of auxiliary throttling arrangement 83 Agent stream, the specific enthalpy of the entrance of evaporator 63 can be reduced., can be effective compared with existing apparatus thereby, it is possible to strengthen refrigeration Improve performance in ground.In addition, the first cold-producing medium stream that shunting obtains returns to the second rotation from the advanced side suction ports 26 of compressor 11 Turn compressing member 20（Middle splenium）, therefore, the first rotary compression element 18 is drawn into from the rudimentary side suction ports 22 of compressor 11 （Low voltage section）Second refrigerant stream amount reduce, for being compressed to the first rotary compression element 18 of middle pressure from low pressure（It is rudimentary Portion）Compressed action amount reduce.As a result, the compression power of compressor 11 reduces, coefficient of refrigerating performance improves.

Here, the effect of above-mentioned so-called separation circulation depends on the first cold-producing medium stream for flowing through Intermediate Heat Exchanger 80 and the The amount of two cold-producing medium streams.That is, if the amount of the first cold-producing medium stream is excessive, the second refrigerant stream that is finally evaporated in evaporator 63 Amount deficiency, if conversely, the amount of the first cold-producing medium stream is very few, separates the decreased effectiveness of circulation.On the other hand, by aiding in throttling The pressure of the first cold-producing medium stream after the decompression of device 83 is the middle pressure of refrigerant loop 1, and it is exactly to control the first system to control pressure in this The amount of cryogen stream.

Here, in the present embodiment, as described above, temperature DT of the computing in the discharging refrigerant from compressor 11（Row Go out temperature sensor 50）In the case of higher than setting DT0, aid in that the direction of the aperture of throttling arrangement 83 acts on to increase the One controlled quentity controlled variable, refrigerant loop 1 middle intermediate pressure section pressure MP be less than by refrigerant loop 1 high side pressure HP and low pressure In the case of the appropriate middle pressure value that lateral pressure LP is solved, the second control of the direction effect of the aperture of throttling arrangement 83 is aided in increase Amount processed, the refrigerant after gas cooler 46 temperature GCT with by Intermediate Heat Exchanger second refrigerant stream after 80s Temperature LT difference（GCT-LT）In the case of less than setting SP, the direction of the aperture of throttling arrangement 83 is aided in make to increase 3rd controlled quentity controlled variable, by the valve opening that these the first~the 3rd controlled quentity controlled variable phase Calais are determined to increase auxiliary throttling arrangement 83 Operational ton.In addition, in the case where temperature LT is less than setting TDT less than the situation or temperature DT-GCT of setting, according to The direction for reducing the valve opening of auxiliary throttling arrangement 83 determines operational ton.

Thus, by the first controlled quentity controlled variable, the temperature DT of discharging refrigerant can be maintained at below setting DT0, passed through Second controlled quentity controlled variable, the middle pressure MP of refrigerant loop 1 can be made suitably to change, thereby, it is possible to suitably keep low-pressure lateral pressure LP, Middle pressure MP, high side pressure HP pressure differential.In addition, by the 3rd controlled quentity controlled variable, can reduce after 80s by Intermediate Heat Exchanger Second refrigerant stream temperature LT, keep refrigeration.Thus, sum it up, can realize refrigerating plant high efficiency and Stabilize.

In addition, control device C in the case where high side pressure HP is in supercritical range, improves setting SP, reduce Setting TDT, meanwhile, in the case where high side pressure HP is in zone of saturation, setting SP is reduced, improves setting TDT, The situation of supercritical range and situation in zone of saturation, the control of change the 3rd are in so as to be divided into high side pressure HP Measure the setting SP and TDT with the first controlled quentity controlled variable and be controlled.

Thus, in the case that high side pressure HP is in zone of saturation, intermediate heat transfer can also be reliably ensure that The degree of superheat of device 80, it can avoid compressor 11 that the unfavorable condition of liquid backflow occurs.In addition, it is in super in high side pressure HP In the case of critical zone, such liquid backflow will not occur, therefore, it is possible to set efficiency comes first.

In addition, using the second controlled quentity controlled variable in above-described embodiment as the pressure in the middle intermediate pressure section according to refrigerant loop 1 In the case of high side pressure HP of the overcompression decision content MPO that MP and low-pressure lateral pressure LP is solved less than refrigerant loop, to Second controlled quentity controlled variable of the direction effect of the aperture of increase auxiliary throttling arrangement, and by the way that the first~the 3rd controlled quentity controlled variable phase Calais is determined Surely the operational ton of the valve opening of throttling arrangement is aided in, it is also same as described above, the middle pressure MP of refrigerant loop can be made suitably to change, by This, can suitably keep low-pressure lateral pressure LP, middle pressure MP, high side pressure HP pressure differential.

In addition, the first cold-producing medium stream come out in the embodiment from Intermediate Heat Exchanger 80 can be by being arranged at cooling during rolling The interflow device 81 of the outlet side of device 38 returns to the outlet side of intercooler 38, can prevent the pressure of intercooler 38 from damaging Lose, can be successfully by the medium voltage side at the cold-producing medium stream interflow come out from Intermediate Heat Exchanger 80 to refrigerant loop 1.

In addition, in embodiment, the refrigerant discharged from refrigerant amount regulating box 100 also flows through the of Intermediate Heat Exchanger 80 One stream 80A, therefore, the refrigerant of discharge can be also used for the second refrigerant stream that cooling flows through second flow path 80B by having Effect.

（D）The control of gas cooler pressure fan

Then, the control that the gas cooler pressure fan 47 of air cooling is carried out to gas cooler 46 as described above is illustrated System.Control device C in the present embodiment is as shown in Fig. 2 input side is connected with high-pressure pressure sensor（High-pressure detection dress Put）48th, low-pressure sensor 32, extraneous gas temperature sensor 56.Here, low-pressure sensor 32 detect pressure and There is certain relation, therefore, control device C is examined by the low-pressure sensor 32 between the evaporating temperature TE of evaporator 63 The conversion pressure of survey obtains the evaporating temperature TE of the refrigerant in evaporator 63.In addition, control device C outlet side is connected with pair Gas cooler 46 carries out the fan electromotor 47M of the gas cooler pressure fan 47 of air cooling.

Control device C controls the rotating speed of gas cooler pressure fan 47, the high pressure for detecting high-pressure pressure sensor 48 Lateral pressure HP becomes target high-pressure THP.That is, control device C is by high-pressure pressure sensor（High-pressure detection means）48 detections High side pressure HP and target high-pressure THP calculate the HP and THP deviation e, according to deviation e, by P（Ratio.And deviation e Size it is proportional, reduce the control in deviation e direction）、D（Differential.Reduce the control in the direction of deviation e changes）Perform ratio Example is differentiated, and decision is used as gas cooler pressure fan 47 derived from operational ton（Fan electromotor 47M）Rotating speed.On The rotating speed, target high-pressure THP is higher, more improves the rotating speed of pressure fan 47, and target high-pressure THP is lower, more reduces pressure fan 47 Rotating speed.

Thus, the evaporating temperature of refrigerants of the control device C in extraneous gas temperature TA and evaporator（By low pressure pressure The low pressure that force snesor 32 detects converts to obtain）TE controls the rotating speed of gas cooler pressure fan 47, even in high pressure Side becomes also control the rotating speed of gas cooler pressure fan 47 in the refrigerating plant R of supercritical pressure, makes high pressure side pressure Power becomes appropriate high-pressure.Thereby, it is possible to reduce because gas cooler pressure fan 47 operate caused by noise, meanwhile, Realize efficient operating.

In the present embodiment, control device C is according to extraneous gas temperature TA and evaporating temperature TE, according to for example, outside gas Temperature TA is lower, more reduces desired value THP, and evaporating temperature TE is higher, and the direction for more improving desired value THP determines that refrigerant returns The desired value THP of the high side pressure on road 1, gas cooler pressure fan 47 is controlled, high side pressure is become desired value THP, so as to consider because extraneous gas temperature TA becomes the state of the refrigerant of saturation circulation and supercritical steam cycle, and root Appropriate high side pressure is realized according to evaporating temperature TE, thereby, it is possible to realize high-efficiency operation.

（E）Separator

On the other hand, in the high pressure for advanced the side outlet 28 and gas cooler 46 for connecting compressor 11 as described above Discharge pipe arrangement 42, which is situated between, is provided with separator 44.The separator 44 will contain in the discharging refrigerant for the high pressure discharged from compressor 11 Oil is separated and trapped with refrigerant, and the separator 44 is connected with the oil return circuit 73 for making the oil of trapping return to compressor 11.This time Fuel tank 79 is provided with oil return line 73, the oil cooler 74 that the oil to trapping is cooled down, in the downstream of oil cooler 74, oil return Loop 73 is divided into two systems, respectively via flow control valve（Motor-driven valve）76 are connected with the closed container 12 of compressor 11.Pressure Middle pressure is maintained at as described above in the closed container 12 of contracting machine 11, and therefore, the oil of trapping passes through the high pressure in separator 44 and close The differential pressure for closing the middle pressure in container 12 is returned in the closed container 12.In addition, the closed container 12 of compressor 11 is provided with detection The oil level float switch 77 of the oily oil level of deposit in the closed container 12.

In addition, as described above, the oil cooler 74 be arranged at the identical wind path 45 of above-mentioned gas cooler 46, by gas Cooler carries out air cooling with pressure fan 47 to it.The high-temperature high-pressure refrigerant discharged from the advanced side outlet 28 of each compressor 11 Collaborate in the downstream of the second rotary compression element 20, be connected by separator 44, gas cooler 46 etc. with showcase unit 5. The oil contained in the high-temperature high-pressure refrigerant flowed into separator 44 is separated and is captured with refrigerant herein.Moreover, compressor Middle pressure is maintained in 11 closed container 12, therefore, the oil trapped is by the high pressure in separator 44 and closed container 12 The differential pressure of interior middle pressure returns to compressor 11 via oil return circuit 28.

The oil flowed into oil return circuit 28 utilizes the oil cooler 74 being disposed in the identical wind path 45 of gas cooler 46 Air cooling is carried out by the operating of pressure fan 47.After the oil cooler 74, two systems are separated into, by flow control valve 76 After return to compressor 11.Thus, become together with high temperature refrigerant high temperature oil cooled down by oil cooler 74 after return to compression Machine 11, rise therefore, it is possible to suppress the temperature of compressor 11.

（F）Refrigerant encapsulation amount governor motion

Then, the refrigerant encapsulation amount governor motion 131 for being arranged at refrigerating plant R is illustrated.The refrigerant encapsulation amount is adjusted Mechanism 131 is arranged in refrigerator unit 3.The refrigerant piping 9 of refrigerant loop 1 in refrigerator unit 3 and delivery pipe 132 Connection connection, the drain valve 133 being made up of motor-driven valve is provided with the delivery pipe 132.In addition, in embodiment, in refrigerant Pipe arrangement 9 is provided with delivery pipe 132 and drain valve 133, still, is not limited to that, can also be as shown in figure 1, installed in centre The middle pressure of the entrance side of cooler 38 goes out the middle grade of pressure suction line 40 refrigerant loop 1 of pipe arrangement 36 or the outlet side of intercooler 38 Middle intermediate pressure section.

Moreover, refrigerant encapsulation amount governor motion 131 is made up of these delivery pipes 132 and drain valve 133, control device C, Drain valve 133 is connected with control device C outlet side.Control device C, which has, to be more than for example as the above-mentioned refrigerant-recovery of beginning The recovery threshold value of one of the condition of action（10.5MPa）, and it is less than above-mentioned high voltage protective value（12MPa）Defined emission regulation Value（Such as 11.5MPa etc.）, according to the emission regulation value（11.5MPa）Such as above-mentioned recovery threshold value（10.5MPa）Opening and closing row Put valve 133.

As described above, control device C rises in the detection pressure of unit outlet side pressure sensor 58 and exceedes recovery threshold Value（10.5MPa）In the case of, start above-mentioned refrigerant amount regulating box 100 and set up the refrigerant of refrigerant amount regulating box 116 Recovery acts.If control device C starts refrigerant collection operation, as described above open electric expansion valve 102, magnetic valve 104, Electric expansion valve 117 and magnetic valve 119, therefore, to refrigerant amount regulating box 100 and set up the system of refrigerant amount regulating box 116 Cryogen recovery ability is maximum.But in the natively superfluous situation of the refrigerant encapsulation amount into refrigerant loop（Cross filling） Under, even if becoming to make the state that can not be reclaimed completely to the refrigerant-recovery ability maximum of each case, unit outlet lateral pressure passes The detection pressure of sensor 58 does not drop to be risen on the contrary.

Here, refrigerating plant R as the present invention operated under conditions of both saturation circulation and supercritical steam cycle In the case of, due to encapsulating temperature during refrigerant into refrigerant loop 1（Extraneous gas temperature）, it is difficult to judge appropriate encapsulation Amount, the encapsulation amount of the low winter encapsulation of extraneous gas temperature became filling in summer, and high-pressure side rises extremely.

Then, detection pressure of the control device C in unit outlet side pressure sensor 58（High side pressure）Rise to State discharge set value（11.5MPa）In the case of, drain valve 133 is opened, via delivery pipe 132 from refrigerant loop 1 to outside Discharge refrigerant.By the discharge of above-mentioned refrigerant, the detection pressure of unit outlet side pressure sensor 58 reduces, accordingly, it is capable to The detection pressure for enough preventing unit outlet side pressure sensor 58 exceedes above-mentioned high voltage protective value（12MPa）, compressor 11 stops Unfavorable condition.Also, the detection pressure of side pressure sensor 58 drops to above-mentioned recovery threshold value in unit outlet（Discharge stops Value.10.5MPa）In the case of, control device C closes drain valve 133, stops discharge refrigerant.Afterwards, above-mentioned refrigerant is performed Recovery acts.Thus, the refrigerant of fill part was discharged.

So, control device C rises extremely in the high side pressure of refrigerant loop 1, is changed into defined discharge set value In the case of above, drain valve 133 is opened, the refrigeration of fill part is crossed from delivery pipe 132 from refrigerant loop 1 to outside drain Agent, therefore, even in seasonal variations, refrigerating plant R is absorbed in the case that refrigerant crosses occupied state, also can automatically will system Appropriate value is arrived in refrigerant encapsulation amount regulation in refrigerant circuit 1.Therefore, in the lower operating of both saturation circulation and supercritical steam cycle The regulation of refrigerating plant R refrigerant encapsulation amount is very easy to.Even if particularly it is being filled into setting system excessively as described embodiments Cryogen amount regulating box 100 or in the case of setting up the degree that refrigerant amount regulating box 116 can not reclaim refrigerant completely, can Above-mentioned occupied state excessively is reliably eliminated by refrigerant encapsulation amount governor motion 131.

In addition, the in this case, low-pressure side of delivery pipe 132 and refrigerant loop 1（Embodiment）Or middle intermediate pressure section connection peace Dress, drain valve 133 discharge refrigerant from low-pressure side, therefore, being capable of the system of stably discharging compared with situation about being discharged from high-pressure side Cryogen, prevent the unfavorable condition of excess emissions refrigerant.

In addition, in embodiment, illustrate to be provided with possess set up refrigerant amount regulating box 116 set up refrigerant amount tune The refrigerating plant R of regulating device 111, still, is not limited to that, the present invention in refrigerator unit 3 also to being provided only with refrigerant amount The refrigerating plant R of regulating box 100 is effective.

In addition, each numerical value not limited to this illustrated in embodiment, can suitably set according to refrigerating plant R.

Claims (11)

1. a kind of refrigerating plant, refrigerant loop is formed by compression set, gas cooler, throttling arrangement, evaporator, its high pressure Side turns into supercritical pressure, it is characterised in that possesses：

Refrigerant amount regulating box, it is connected with the refrigerant loop；

Control device, the on high-tension side circulating refrigerant of the refrigerant loop is recovered to the refrigerant amount regulating box by it, The refrigerant for being recovered to the refrigerant amount regulating box is discharged to the middle intermediate pressure section or low-pressure side of the refrigerant loop,

The control device by refrigerant-recovery to the refrigerant amount regulating box while, from the refrigerant amount regulating box discharge make Cryogen, also, the desired value of the high side pressure based on the refrigerant loop and the high side pressure is adjusted to the refrigeration Dosage regulating box reclaims refrigerant and the degree from the refrigerant amount regulating box discharging refrigerant, thus, controls the refrigerant Circularly cooling dosage in loop.

2. refrigerating plant as claimed in claim 1, it is characterised in that

Evaporating temperature of the control device based on the refrigerant in extraneous gas temperature and the evaporator determines the refrigeration The desired value of the high side pressure in agent loop.

3. refrigerating plant as claimed in claim 1, it is characterised in that

Carbon dioxide is used as the refrigerant.

4. a kind of refrigerating plant, refrigerant loop is formed by compression set, gas cooler, throttling arrangement, evaporator, its high pressure Side turns into supercritical pressure, it is characterised in that possesses：

Refrigerant amount regulating box, it is connected with the refrigerant loop；

Control device, the on high-tension side circulating refrigerant of the refrigerant loop is recovered to the refrigerant amount regulating box by it, The refrigerant for being recovered to the refrigerant amount regulating box is discharged to the middle intermediate pressure section or low-pressure side of the refrigerant loop,

The control device is changed to the refrigerant amount regulating box with the rising of the on high-tension side pressure of the refrigerant loop Refrigerant-recovery speed.

5. refrigerating plant as claimed in claim 4, it is characterised in that

The control device makes to the refrigerant amount regulating box with the rising of the high side pressure of the refrigerant loop Refrigerant-recovery speed rises.

6. refrigerating plant as claimed in claim 4, it is characterised in that

The control device by refrigerant-recovery to the refrigerant amount regulating box while, the height based on the refrigerant loop Lateral pressure is pressed from the refrigerant amount regulating box discharging refrigerant, also, with the high side pressure of the refrigerant loop Drop, from the refrigerant amount regulating box slowly discharging refrigerant.

7. refrigerating plant as claimed in claim 6, it is characterised in that possess：

First connected loop, it connects the high-pressure side of the refrigerant amount regulating box and the refrigerant loop；

Second connected loop, it connects the middle intermediate pressure section or low of the bottom of the refrigerant amount regulating box and the refrigerant loop Press side；

First valve gear, it is arranged at first connected loop, and has throttling function；

Second valve gear, it is arranged at second connected loop,

The control device is changed to the refrigerant of the refrigerant amount regulating box by the valve opening of first valve gear and returned Speed is received, by the opening time of second valve gear from the refrigerant amount regulating box slowly discharging refrigerant.

8. refrigerating plant as claimed in claim 7, it is characterised in that possess：

Third connecting loop, it connects the middle intermediate pressure section of the top of the refrigerant amount regulating box and the refrigerant loop；

3rd valve gear, it is arranged at the third connecting loop,

The control device opens the 3rd valve gear when by refrigerant-recovery to the refrigerant amount regulating box.

9. the refrigerating plant as any one of claim 4~8, it is characterised in that

The control device is controlled to the refrigerant amount on the basis of the desired value of the high side pressure of the refrigerant loop Regulating box reclaims refrigerant and from the refrigerant amount regulating box discharging refrigerant.

10. refrigerating plant as claimed in claim 9, it is characterised in that

Evaporating temperature of the control device based on the refrigerant in extraneous gas temperature and the evaporator determines the refrigeration The desired value of the high side pressure in agent loop.

11. the refrigerating plant as any one of claim 4~8, it is characterised in that

Carbon dioxide is used as the refrigerant.