`
`Europilsthes
`Patenta mt
`European
`Patent Office
`Office eumpéen
`des brevets
`
`(11)
`
`EP2019 270 A1
`
`(12)
`
`EUROPEAN PATENT APPLICATION
`published in accordance with Art. 153(4) EPC
`
`(43) Date of publication:
`28.01.2009 Bulletin 2009/05
`
`(51)
`
`Int Cl.:
`F253 7/00 (2005-01)
`
`F25D 19/00 (2006.01)
`
`(21) Application number: 077432805
`
`(22) Date of filing: 14.05.2007
`
`
`
`(84) Designated Contracting States:
`AT BE BG CH CY CZ DE DK EE ES FI FR GB GR
`HU IE IS IT LI LT LU LV MC MT NL PL PT RO SE
`SI SK TR
`
`Designated Extension States:
`AL BA HR MK RS
`
`(30) Priority: 15.05.2006 JP 2006135287
`
`(71) Applicant: SANYO ELECTRIC CO., LTD.
`Moriguchi-shi, Osaka 570-8677 (JP)
`
`(54)
`
`REFRIGERATION SYSTEM
`
`There is disclosed a refrigeration apparatus in-
`(57)
`cluding a cascade heat exchanger and capable of reduc-
`ing the depth dimension of the apparatus itself without
`being influenced by the thickness dimension of an insu-
`lating material for covering the cascade heat exchanger,
`so that the apparatus can easily be carried indoors
`through a usual carrying entrance. In a refrigeration ap-
`paratus 1
`including a high-temperature-side refrigerant
`circuit 25 and a Iow—temperature—side refrigerant circuit
`38, an evaporator 34 ofthe high—temperature—side refrig—
`erant circuit 25 and a condensing pipe 42 of the low—
`temperature-side refrigerant circuit 25 constitute a cas-
`cade heat exchanger43, and an evaporation pipe 62 of
`the Iow-temperature-side refrigerant circuit 38 is config-
`ured to cool a storage chamber 4 constituted in an insu-
`lating box body 2 to an extremely low temperature. The
`apparatus includes a mechanical chamber 3 which is
`constituted by the side of an insulating box body 2 and
`in which a compressor 10 and the like are installed, and
`an insulating structure 70 in which the periphery of the
`cascade heat exchanger 34 is surrounded with an insu—
`lating material is arranged in a side wall of the insulating
`box body 2 on the side of the mechanical chamber 3.
`
`(86)
`
`International application number:
`PCT/J P2007/059845
`
`(87)
`
`International publication number:
`WO 2007I132804 (22.11.2007 Gazette 2007/47)
`
`(72)
`
`Inventor: TAKASUGI, Katsuji
`Ota—shi
`
`Gunma 370-0426 (JP)
`
`(74)
`
`Representative: Grey, Ian Michael et al
`Venner Shipley LLP
`20 Little Britain
`
`London EC1A 7DH (GB)
`
`FIG. 9
`
`
`
`Printed by Jouve, 75001 PARIS (FR)
`
`EP2019270A1
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`EP2019 270 A1
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`Description
`
`BACKGROUND OF THE INVENTION
`
`[0001] The present invention relates to a refrigeration
`apparatus including a high-temperature-side refrigerant
`circuit and a low-temperature-side refrigerantcircuit each
`constituting an independent refrigerant closed circuit in
`which a refrigerant discharged from a compressor is con-
`densed and then evaporated to exert a cooling function,
`an evaporator of the high—temperature—side refrigerant
`circuit and a condenser of the low—temperature—side re—
`frigerant circuit constituting a cascade heat exchanger,
`an evaporator ofthe low-temperature-side refrigerant cir-
`cuit being configured to cool a storage chamber consti-
`tuted in an insulating box body to an extremely low tem-
`perature.
`[0002] Heretofore, atwo-dimensional refrigeration ap-
`paratus has been used as a refrigeration apparatus hav-
`ing an extremely low temperature for use in storing, for
`example, cells, microorganisms and the like in a biolog-
`ical field. FIG. 10 shows a refrigerant circuit diagram of
`a refrigeration apparatus 135 using the two—dimensional
`refrigeration apparatus. A refrigerant circuit 100 is con—
`stituted of a high—temperature—side refrigerant cycle 101
`and a low-temperature-side refrigerant cycle 102. A dis-
`charge-side pipe 103D of a compressor 103 constituting
`the high-temperature-side refrigerant cycle 101 is con-
`nected to an auxiliary condenser 105, and the auxiliary
`condenser 105 is connected to a frame pipe 104 (forthe
`frame pipe, referto a frame pipe 27 ofthe present appli-
`cation), and then connected to a condenser 107 via an
`oil cooler 106 ofthe compressor 103. The condenser 1 07
`is cooled by a blower 1 16 for the condenser. Moreover,
`an outlet—side refrigerant pipe of the condenser 107 is
`connectedto an evaporator 1 1 O as an evaporatorportion
`constituting the evaporator successively through a drier
`108 and a pressure reducing unit 109. An outlet-side re-
`frigerant pipe of the evaporator 110 is connected to an
`accumulator 111, and a refrigerant pipe exiting from the
`accumulator 111 is connected to a suction-side pipe
`1038 of the compressor 103.
`[0003] On the other hand, a discharge-side pipe 113D
`of a compressor 113 constituting the low-temperature-
`side refrigerant cycle 102 is connected to an oil separator
`114, and a refrigerant pipe connected to the outlet side
`of this oil separator 114 is connected to a condensing
`pipe 115 as a high—temperature—side pipe inserted into
`the evaporator 1 1 0. This condensing pipe 115 constitutes
`a cascade heat exchanger 130 togetherwith the evapo-
`rator 110.
`
`[0004] Moreover, a discharge pipe connected to the
`outlet side of the condensing pipe 115 is connected to a
`first gas-liquid separator 1 1 6 through a drier 1 31 , and the
`gas-phase refrigerant separated by the gas-liquid sepa-
`rator 116 passes through a first intermediate heat ex-
`changer 117 via a gas-phase pipe to flow into a second
`gas-liquid separator 1 18. A liquid-phase refrigerant sep-
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`arated by the gas-liquid separator 116 passes through a
`drier 119 and a pressure reducing unit 120 via a liquid-
`phase pipe, flows into the first intermediate heat ex-
`changer 117, and evaporates the gas-phase refrigerant
`to cool.
`
`[0005] The liquid-phase refrigerant separated by the
`second gas-liquid separator 118 passes through a drier
`121 and a pressure reducing unit 122 viathe liquid-phase
`pipe to flow into a second intermediate heat exchanger
`123. The gas-phase refrigerant separated bythe second
`gas—liquid separator 118 passes through the second in—
`termediate heat exchanger 1 23 viathe liquid—phase pipe,
`and passes through a third intermediate heat exchanger
`124 and a drier 125 to flow into a pressure reducing unit
`126. The pressure reducing unit 126 is connected to an
`evaporation pipe 127 as an evaporatorarranged in a heat
`exchanging manner in an innerwall of an insulating box
`body 132 of the refrigeration apparatus on a storage
`chamber side, and the evaporation pipe 127 is further
`connected to the third intermediate heat exchanger 124.
`[0006] The third intermediate heat exchanger 124 is
`successively connected to the second and first interme-
`diate heat exchangers, and then connected to a suction—
`side pipe 1138 of the compressor 113. This suction—side
`pipe 1138 is connected to an expansion tank 128 for
`receiving the refrigerant during the stop of the compres-
`sor 113 through a pressure reducing unit 129.
`[0007]
`In this refrigeration apparatus 135, the evapo-
`ration pipe 127 of the low-temperature-side refrigerant
`cycle 102 reaches an extremely low temperature of
`-150°C or less, and even the cascade heat exchanger
`130 reaches a low temperature of about -40°C. There-
`fore, a cascade heat exchanger 130 part needs to be
`sufficiently insulated.
`In a conventional constitution, as
`shown in FIG. 11, the cascade heat exchanger 130 is
`provided with an externally opened storage recess por—
`tion 133 beforehand secured in the back surface of the
`
`insulating box body 132 constituting the main body ofthe
`refrigeration apparatus 135, and the heat exchanger is
`incorporated after foaming an insulating material of the
`insulating box body 132 (see Japanese Patent Applica-
`tion Laid-Open No. 2000-105047).
`[0008] Moreover, in the peripheral surface of this cas-
`cade heat exchanger 130, the insulating material is po-
`sitioned, and a flat-plate-like insulating material 134 is
`received in a space between the storage recess portion
`133 and the cascade heat exchanger 130 so as to cover
`the whole opening.
`[0009] However, since the cascade heat exchanger
`130 has a low temperature of about -40°C, dew might be
`attached to the outer surface of the main body around
`the heat exchanger. Therefore, the corresponding part
`needs to be sufficiently insulated, and an insulating struc-
`ture is constituted so that the thickness of the insulating
`material 134 is remarkably increased, and the material
`is covered with a cover part from the outside. However,
`when the thickness of the insulating material 134 is in-
`creased, a protruding part corresponding to the thickness
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`ofthe insulating material 134 is present in the back sur-
`face part of the main body, which causes a problem that
`the protruding part disturbs the installation of the refrig-
`eration apparatus 135.
`[0010]
`In particular, in a case where the refrigeration
`apparatus 135 is carried indoors, there sometimes oc-
`curs a disadvantage that the apparatus is stuck in the
`carrying entrance of an installation place and that it be-
`comes difficult to carry the apparatus indoors. Therefore,
`to smoothly perform a carrying operation, in a case where
`a product is designed so that the thickness of the insu—
`lating material of this protruding part is secured over the
`whole main body, there is a problem that when an outer
`dimension is not increased, a volume in the storage
`chamber decreases.
`
`[0011] To solve the problem, in a refrigeratordisclosed
`in
`Japanese
`Patent Application Laid-Open No.
`2000-105047, a constitution is employed in which the
`insulating material covering the back surface of the cas-
`cade heat exchanger is covered with an inner cover, a
`second insulating material and an outer cover covering
`the material are provided outside the inner cover, and
`the outer cover is detachably attached to the inner cover
`with a plurality of small screws. In consequence, during
`the carrying, the carrying operation of the refrigeration
`apparatus is performed in a state in which the outer cover
`is removed, which avoids a disadvantage that the pro-
`truding part is stuck in the carrying entrance as described
`above.
`
`[0012] However, according to such a constitution,
`even in the installation place, the protruding part is still
`present in the back surface part of the main body. Even
`in such a case, owing to the product design in which the
`thickness of the protruding part is secured overthe whole
`main body, there has been a problem that the storage
`volume decreases with respect to a depth as the outer
`dimension. Moreover, there has been a problem that an
`operation of attaching the outer cover needs to be per-
`formed afterthe installation, thereby resulting in a labo-
`rious carrying operation.
`
`SUMMARY OF THE INVENTION
`
`[0013] The present invention has been developed to
`solve the conventional technical problem, and an object
`thereof is to provide a refrigeration apparatus including
`a cascade heat exchanger and capable of reducing the
`depth dimension of the apparatus itself without being in—
`fluenced by the thickness dimension of an insulating ma-
`terial for covering the cascade heat exchanger, so that
`the apparatus can easily be carried indoors through a
`usual carrying entrance.
`[0014] A refrigeration apparatus of the present inven-
`tion is characterized by comprising: a high-temperature-
`side refrigerant circuit and a low-temperature-side refrig-
`erantcircuit each constituting an independent refrigerant
`closed circuit in which a refrigerant discharged from a
`compressor is condensed and then evaporated to exert
`
`a cooling function, an evaporator of the high-tempera-
`ture-side refrigerant circuit and a condenser of the low-
`temperature-side refrigerant circuit constituting a cas-
`cade heat exchanger, an evaporator of the low-temper-
`ature-side refrigerant circuit being configured to cool a
`storage chamber constituted in an insulating box body
`to an extremely low temperature, the refrigeration appa-
`ratus further comprising: a mechanical chamber which
`is constituted by the side of the insulating box body and
`in which the compressor and the like are installed; and
`an insulating structure in which the periphery of the cas—
`cade heat exchanger is surrounded with an insulating
`material and which is arranged in a side wall of the insu-
`lating box body on the side of the mechanical chamber.
`[0015] A refrigeration apparatus of the invention of a
`second aspect is characterized by comprising: a com-
`pressor; a condenser; an evaporator; and a plurality of
`intermediate heat exchangers and a plurality of pressure
`reducing units connected in series so that a refrigerant
`fed back from the evaporator circulates, wherein a plu-
`rality of types of non-azeotropic mixed refrigerants are
`introduced, a condensed refrigerant in the refrigerants
`passed through the condenser is allowed to join the in—
`termediate heat exchangerthrough the pressure reduc—
`ing unit, a non—condensed refrigerant in the refrigerants
`is cooled bythe intermediate heat exchangerto succes-
`sively condense the refrigerant having a lower boiling
`point, and the refrigerant having the lowest boiling point
`is allowed to flow into the evaporator through the final
`stage of the pressure reducing unit, to cool a storage
`chamber constituted in the insulating box body to an ex-
`tremely low temperature, the refrigeration apparatus fur-
`ther comprising: a mechanical chamber which is consti-
`tuted by the side of the insulating box body and in which
`the compressor and the like are installed; and an insu—
`lating structure in which the periphery of each interme—
`diate heat exchanger is surrounded with an insulating
`material and which is arranged in a side wall of the insu-
`lating box body on the side of the mechanical chamber.
`[0016] A refrigeration apparatus of the invention of a
`third aspect is characterized by comprising: a high-tem-
`perature-side refrigerant circuit and a low-temperature-
`side refrigerant circuit each constituting an independent
`refrigerantclosed circuit in which a refrigerant discharged
`from a compressor is condensed and then evaporated
`to exert a cooling function, the low-temperature-side re-
`frigerant circuit having the compressor, a condenser, an
`evaporator, and a plurality of intermediate heat exchang—
`ers and a plurality of pressure reducing units connected
`in series so that the refrigerant fed back from the evap-
`orator circulates, wherein a plurality of types of non-aze-
`otropic mixed refrigerants are introduced, a condensed
`refrigerant in the refrigerants passed through the con-
`denseris allowedtojoin the intermediate heat exchanger
`through the pressure reducing unit, a non-condensed re-
`frigerant in the refrigerants is cooled by the intermediate
`heat exchangerto successively condense the refrigerant
`having a lower boiling point, the refrigerant having the
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`EP2019 270 A1
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`lowest boiling point is allowed to flow into the evaporator
`through the final stage of the pressure reducing unit, an
`evaporator of the high-temperature-side refrigerant cir-
`cuit and the condenser of the low-temperature-side re-
`frigerantcircuit constitute acascade heat exchanger, and
`the evaporator of the low-temperature-side refrigerant
`circuit is configured to cool astorage chamber constituted
`in the insulating box body to an extremely low tempera-
`ture, the refrigeration apparatusfurthercomprising: ame-
`chanical chamber which is constituted by the side of the
`insulating box body and in which the compressor and the
`like are installed; and an insulating structure in which the
`peripheries of the cascade heat exchanger and each in-
`termediate heat exchanger are surrounded with an insu-
`lating material and which is arranged in a side wall ofthe
`insulating box body on the side of the mechanical cham-
`ber.
`
`[0017] A refrigeration apparatus of the invention of a
`fourth aspect is characterized in that in the above inven-
`tions, the insulating box body is formed of a composite
`constitution of vacuum insulating panels and a foam in-
`sulating material, and the vacuum insulating panels are
`arranged in front and rearwalls ofthe insulating box body
`and a side wall of the insulating box body on a side op—
`posite to the mechanical chamber.
`[0018] A refrigeration apparatus of the invention of a
`fifth aspect is characterized in that in the above inven-
`tions, the insulating structure is detachably inserted from
`the backside, the front side or the upside.
`[0019] A refrigeration apparatus of the invention of a
`sixth aspect is characterized in that in the above inven-
`tion, a pipe from the insulating structure is opposed to
`the surface in a direction in which the insulating structure
`is inserted or removed.
`
`[0020] According to the present invention, the refrig—
`eration apparatus comprises the high—temperature—side
`refrigerant circuit and the low—temperature—side refriger—
`ant circuit each constituting the independent refrigerant
`closed circuit in which the refrigerant discharged from
`the compressor is condensed and then evaporated to
`exert the cooling function. The evaporator of the high-
`temperature-side refrigerantcircuit and the condenser of
`the low-temperature-side refrigerant circuit constitute the
`cascade heat exchanger, and the evaporator of the low-
`temperature-side refrigerant circuit is configured to cool
`the storage chamber constituted in the insulating box
`body to the extremely low temperature. The refrigeration
`apparatus further comprises the mechanical chamber
`which is constituted by the side ofthe insulating box body
`and in which the compressor and the like are installed,
`and the insulating structure in which the periphery of the
`cascade heat exchanger is surrounded with the insulat-
`ing material and which is arranged in the side wall of the
`insulating box body on the side of the mechanical cham-
`ber. Therefore, as compared with a case where the cas-
`cade heat exchangeris installed on the back surface por-
`tion of the insulating box body, the depth dimension of
`the whole apparatus can be reduced.
`
`In consequence, it is possible to avoid a disad-
`[0021]
`vantage that owing to the presence of a protruding part
`of the insulating structure for surrounding the cascade
`heat exchanger, the apparatus is stuck in a usual carrying
`entrance. Therefore, the refrigeration apparatus can eas-
`ily be carried inwards or outwards without especially re-
`ducing a storage volume. Moreover, even in an installa-
`tion place, the insulating structure for surrounding the
`cascade heat exchanger does not protrude externally
`from the back surface of the apparatus, so that an area
`required for installation can be decreased.
`[0022] Accordingto the invention ofthe second aspect,
`the refrigeration apparatus comprises the compressor,
`the condenser, the evaporator, and the plurality of inter-
`mediate heat exchangers and the plurality of pressure
`reducing units connected in series so that the refrigerant
`fed back from the evaporator circulates. The plurality of
`types of non-azeotropic mixed refrigerants are intro-
`duced,
`the condensed refrigerant
`in the refrigerants
`passed through the condenser is allowed to join the in-
`termediate heat exchangerthrough the pressure reduc-
`ing unit, the non-condensed refrigerant in the refrigerants
`is cooled bythe intermediate heat exchangerto succes—
`sively condense the refrigerant having the lower boiling
`point, and the refrigerant having the lowest boiling point
`is allowed to flow into the evaporator through the final
`stage of the pressure reducing unit, to cool the storage
`chamber constituted in the insulating box body to the
`extremely low temperature. The refrigeration apparatus
`further comprises the mechanical chamberwhich is con-
`stituted bythe side ofthe insulating box body and in which
`the compressor and the like are installed, and the insu-
`lating structure in which the periphery of each interme-
`diate heat exchanger is surrounded with the insulating
`material and which is arranged in the side wall of the
`insulating box body on the side of the mechanical cham—
`ber. Therefore, as compared with a case where the in—
`sulating structure in which the periphery of each interme-
`diate heat exchanger is surrounded with the insulating
`material is installed on the back surface portion of the
`insulating box body as in the conventional example, the
`depth dimension ofthe whole apparatus can be reduced.
`[0023]
`In consequence, it is possible to avoid the dis-
`advantage that owing to the presence of the protruding
`part oftheinsulating structure forsurroundingthe periph-
`ery of each intermediate heat exchanger, the apparatus
`is stuck in the usual carrying entrance. Therefore, the
`refrigeration apparatus can easily be carried inwards or
`outwards without especially reducing the storage vol-
`ume. Moreover, even in the installation place, the insu-
`lating structure for surrounding the periphery of each in-
`termediate heat exchanger does not protrude externally
`from the back surface of the apparatus, so that the area
`required for installation can be decreased.
`[0024] According to the invention of the third aspect,
`the refrigeration apparatus comprises the high-temper-
`ature-side refrigerant circuit and the low-temperature-
`side refrigerant circuit each constituting the independent
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`EP2019 270 A1
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`in which the refrigerant dis-
`refrigerant closed circuit
`charged from the compressor is condensed and then
`evaporated to exert the cooling function. The low-tem-
`perature-side refrigerant circuit has the compressor, the
`condenser, the evaporator, and the plurality of interme-
`diate heat exchangers and the plurality of pressure re-
`ducing units connected in series so that the refrigerant
`fed back from the evaporator circulates. The plurality of
`types of non-azeotropic mixed refrigerants are intro-
`duced,
`the condensed refrigerant
`in the refrigerants
`passed through the condenser is allowed to join the in—
`termediate heat exchangerthrough the pressure reduc—
`ing unit, the non-condensed refrigerantin the refrigerants
`is cooled by the intermediate heat exchanger to succes-
`sively condense the refrigerant having the lower boiling
`point, the refrigerant having the lowest boiling point is
`allowedtoflowinto the evaporatorthroughthefinalstage
`of the pressure reducing unit, the evaporator of the high-
`temperature-side refrigerantcircuit and the condenser of
`the low-temperature-side refrigerant circuit constitute the
`cascade heat exchanger, and the evaporator of the low-
`temperature-side refrigerant circuit is configured to cool
`the storage chamber constituted in the insulating box
`body to the extremely low temperature. The refrigeration
`apparatus further comprises the mechanical chamber
`which is constituted bythe side ofthe insulating box body
`and in which the compressor and the like are installed,
`and the insulating structure in which the peripheries of
`the cascade heat exchanger and each intermediate heat
`exchanger are surrounded with the insulating material
`and which is arranged in the side wall of the insulating
`box body on the side ofthe mechanical chamber. There-
`fore, as compared with a case where the insulating struc-
`ture in which the peripheries of the cascade heat ex-
`changer and each intermediate heat exchanger are sur—
`rounded with the insulating material is installed on the
`back surface portion of the insulating box body as in the
`conventional example, the depth dimension ofthe whole
`apparatus can be reduced.
`[0025]
`In consequence, it is possible to avoid the dis-
`advantage that owing to the presence of the protruding
`part ofthe insulating structurefor surroundingthe periph-
`eries of the cascade heat exchanger and each interme-
`diate heat exchanger, the apparatus is stuck in the usual
`carrying entrance. Therefore, the refrigeration apparatus
`can easily be carried inwards or outwards without espe-
`cially reducing the storage volume. Moreover, even in
`the installation place, the insulating structure for sur—
`rounding the peripheries of the cascade heat exchanger
`and each intermediate heat exchangerdoes not protrude
`externally from the back surface ofthe apparatus, so that
`the area required for installation can be decreased.
`[0026] According to the invention ofthe fourth aspect,
`inthe aboveinventions,theinsulating box bodyisformed
`of the composite constitution of the vacuum insulating
`panels and the foam insulating material, and the vacuum
`insulating panels are arranged in the front and rearwalls
`of the insulating box body and the side wall of the insu-
`
`lating box body on the side opposite to the mechanical
`chamber.
`In consequence, unlike the conventional ex-
`ample, the back surface of the insulating box body is not
`provided with the insulating structure for surrounding the
`peripheries ofthe cascade heat exchanger and each in-
`termediate heat exchanger. Therefore, the vacuum insu-
`lating panels can be arranged in the front and rear walls
`of the insulating box body and the side wall of the insu-
`lating box body on the side opposite to the mechanical
`chamberwithout being influenced by the insulating struc-
`ture. Consequently, the leakage of cold from the storage
`chamber can be decreased, and the wasting of useless
`cooling energy can be suppressed.
`[0027]
`In particular, the vacuum insulating panels are
`arranged in the front and rear walls of the insulating box
`body constituted so as to face the outside and the side
`wall of the insulating box body on the side opposite to
`the mechanical chamber. Therefore, even when the stor-
`age chamber is cooled to an extremely low temperature
`of, for example, -80°C or less, the insulating performance
`of the insulating box body itself can be improved, and
`dimensions can be reduced. Even when an outer dimen-
`
`sion is similarto that ofthe conventional example, a stor—
`age volume in the storage chamber can be enlarged.
`Alternatively, even when the storage volume is similarto
`that of the conventional example, the outer dimension
`can be reduced. In consequence, an area required for
`installing the refrigeration apparatus can be decreased.
`[0028] According to the invention of the fifth aspect, in
`the above inventions, the insulating structure is detach-
`ably inserted from the backside, the front side orthe up-
`side.
`In consequence, the insulating structure in which
`the cascade heat exchanger and the intermediate heat
`exchangers are integrated with the insulating material is
`inserted from the backside, the front side or the upside,
`the cascade heat exchanger and the intermediate heat
`exchangers can easily be assembled in the main body,
`and assembling operability can be improved. Moreover,
`when the integrated insulating structure is extracted to
`the backside, the front side orthe upside, the insulating
`structure can be removed from the main body, and a
`maintenance operation of the cascade heat exchanger
`and the intermediate heat exchangers can easily be per-
`formed.
`
`[0029] Moreover, accordingto the invention ofthe sixth
`aspect, in the above invention, the pipe from the insulat-
`ing structure is opposed to the surface in the direction in
`which the insulating structure is inserted or removed. In
`consequence, afterinstallingthe compressorandthe like
`in the mechanical chamber, the insulating structure is
`finally inserted. In this state, pipes from the mechanical
`chamber side orthe insulating box body side can easily
`be connected, and piping operability and assembling op-
`erability can be improved.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0030]
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`1 is a perspective view of a refrigeration appa-
`F G.
`ratus to which the present invention is applied;
`F G. 2 is a front view of the refrigeration apparatus
`of FIG. 1;
`F G. 3 is a plan view of the refrigeration apparatus
`of FIG. 1;
`F G. 4 is a side view in a state in which a storage
`chamber is seen through the refrigeration apparatus
`of FIG. 1;
`F G. 5 is a perspective view of the refrigeration ap-
`paratus in a state in which a top panel is opened;
`F G. 6 is a refrigerant circuit diagram of the refriger—
`ation apparatus of FIG. 1;
`F G. 7 is aperspectiveview ofan insulating structure;
`F G. 8 is a perspective view in a state in which an
`insulating material of the insulating structure has
`been removed;
`F G. 9 is a rear perspective view of the refrigeration
`apparatus showing a state in which the insulating
`structure is attached;
`F G. 10 is a refrigerant circuit diagram of a conven-
`tional refrigeration apparatus; and
`F G. 11 is a rearperspective view of the conventional
`refrigeration apparatus.
`
`
`
`
`DETAILED DESCRIPTION OF THE PREFERRED EM-
`BODIMENT
`
`[0031] An embodiment of the present invention will
`hereinafter be described with reference to the drawings.
`FIG.
`1 is a perspective view of a refrigeration apparatus
`1
`to which the present invention is applied, FIG. 2 is a
`front view of the refrigeration apparatus 1, FIG. 3 is a
`plan view ofthe refrigeration apparatus 1 , FIG. 4 is a side
`view in a state in which a storage chamber 4 is seen
`through the refrigeration apparatus 1, and FIG. 5 is a
`perspective view ofthe refrigeration apparatus 1 in a state
`in which a top panel 5 is opened. The refrigeration ap-
`paratus 1 of the present embodiment is suitable forstor-
`ing, atan extremely Iowtemperature, forexample, a living
`tissue, a specimen or the like to be stored at a low tem-
`peraturefor a long time, and a main body ofthe apparatus
`is constituted of an insulating box body 2 which opens in
`an upper surface, and a mechanical chamber3 which is
`positioned by the side of the insulating box body 2 and
`in which a compressor 10 and the like are installed.
`[0032] This insulating box body 2 is constituted of an
`outer box 6 made of a steel plate and an inner box 7
`made of a satisfactorily thermally conductive metal such
`as aluminum, the boxes having opened upper surfaces.
`The insulating box body is also constituted of a breaker
`8 connecting the upper ends of both the boxes 6, 7 to
`each other, and an insulating material 9 with which a
`space surrounded bythe outer box 6, the inner box 7 and
`the breaker 8 is filled by an on-site foam system and
`which is made of a polyurethane resin. The inside of the
`inner box 7 is the storage chamber 4 having an open
`upper surface.
`
`In the present embodiment, a targeted temper-
`[0033]
`ature (hereinafter referred to as the in-chambertemper-
`ature) in the storage chamber 4 is set to, for example,
`-150°C or less. Therefore, the insulating box body2 which
`separates the inside of the storage chamber 4 and out-
`side air needs to have large insulating capability against
`asetlowin-chambertemperature around 0°C.Therefore,
`to secure the insulating capability only by the insulating
`material 9 made of the polyurethane resin, the material
`has to be formed to be remarkably thick. There is also a
`problem that a sufficient storage amount in the storage
`chamber 4 cannot be secured with a limited main body
`dimension.
`
`To solve the problem, in the insulating box body
`[0034]
`2 of the present embodiment, vacuum insulating panels
`12 made of glass wool are arranged in the inner wall
`surfaces of a front wall 6A of the outer box 6, a rear wall
`SB and a side wall SC positioned on a side opposite to a
`side provided with the mechanical chamber 3. The panels
`are tentatively fixed with an adhesive double coated tape,
`and then a space between both the boxes 6 and 7 is filled
`with the insulating material 9 bythe on-site foam system.
`[0035]
`To constitute this vacuum insulating panel 12,
`glass wool having insulating properties is received in a
`container constituted of a multilayered film made of alu—
`minum, a synthetic resin orthe like which does not have
`any gas permeability. Afterward, air is discharged from
`the container by predetermined vacuum exhaust means,
`and an opening of the container is thermally sealed and
`joined.
`In consequence, since the vacuum insulating panel 12
`has the insulating performance, the thickness dimension
`of the insulating material 9 is decreased as compared
`with a conventional example, but the same insulating ef-
`fect can be obtained.
`
`[0036] On the other hand, an evaporator (an evapora—
`tion pipe) 62 constituting a refrigerant circuit of a cooling
`apparatus R described later in detail is attached to the
`peripheral surface of the inner box 7 on the insulating
`material 9 side in a heat exchange manner.
`[0037] Moreover, as shown in FIGS. 2 and 4, the upper
`surface of the breaker 8 ofthe insulating box body 2 hav-
`ing the above constitution is formed in a staircase-like
`shape, and an insulating door 13 is provided on the sur-
`face via a packing (not shown) so that the insulating door
`is rotatable around one end, that is, the rear end of the
`door in the present embodiment by pivotable members
`14, 14. Moreover, the upper—surface opening of the stor—
`age chamber 4 is provided with an openable/closable
`inner lid