VEHICULAR REFRIGERATION CYCLE UNIT AND VEHICULAR AIR CONDITIONING DEVICE

Provided is a vehicular refrigeration cycle unit interposed between a vehicle-exterior heat exchanger and a vehicle-interior heat exchanger and that exchanges heat between secondary refrigerants flowing through the vehicle-exterior heat exchanger and the vehicle-interior heat exchanger, respectively, the vehicular refrigeration cycle unit being provided with a refrigeration cycle including a compressor, a condenser, an expansion valve, and an evaporator through which a primary refrigerant sequentially flows, and the distance between the compressor and the evaporator is longer than the distance between the compressor and the condenser.

TECHNICAL FIELD

The present disclosure relates to a vehicular refrigeration cycle unit and a vehicular air conditioning device.

BACKGROUND ART

Patent Document 1 discloses a refrigeration cycle constituting a vehicular heat management system and including a compressor, a heat medium cooler (evaporator), and a heat medium heater (condenser) accommodated in a case having thermal insulating properties.

CITATION LIST

Patent Literature

Patent Document 1: JP 2014-201224 A

SUMMARY OF INVENTION

Technical Problem

The compressor described in Patent Document 1 compresses a refrigerant flowing through the vehicular heat management system, and thus the temperature of the compressor is higher than that of other devices. Since the compressor is disposed adjacent to the evaporator with a part of the case interposed therebetween, the compressor transfers heat more preferentially to the evaporator than to the condenser. Therefore, there is a problem that an increase in the temperature of the evaporator by the compressor is higher than an increase in the temperature of the condenser by the compressor. When the temperature of the evaporator increases, the heat exchange performance of the evaporator decreases.

The present disclosure has been made to solve the above-described problem, and an object thereof is to provide a vehicular refrigeration cycle unit and a vehicular air conditioning device that can suppress a decrease in a heat exchange efficiency of an evaporator.

Solution to Problem

To solve the above-described problem, a vehicular refrigeration cycle unit according to the present disclosure is a vehicular refrigeration cycle unit interposed between a vehicle-exterior heat exchanger and a vehicle-interior heat exchanger and being configured to exchange heat between respective secondary refrigerants flowing through the vehicle-exterior heat exchanger and the vehicle-interior heat exchanger. The vehicular refrigeration cycle unit is provided with a refrigeration cycle including a compressor, a condenser, an expansion valve, and an evaporator through which a primary refrigerant sequentially flows. A distance between the compressor and the evaporator is longer than a distance between the compressor and the condenser.

Further, a vehicular refrigeration cycle unit according to the present disclosure is a vehicular refrigeration cycle unit which is interposed between a vehicle-exterior heat exchanger and a vehicle-interior heat exchanger and exchanges heat between respective secondary refrigerants flowing through the vehicle-exterior heat exchanger and the vehicle-interior heat exchanger. The vehicular refrigeration cycle unit is provided with a refrigeration cycle including a compressor, a condenser, an expansion valve, and an evaporator through which a primary refrigerant sequentially flows. A distance between a discharge port for the primary refrigerant at the compressor and the evaporator is longer than a distance between the discharge port and the condenser.

Furthermore, a vehicular refrigeration cycle unit according to the present disclosure is a vehicular refrigeration cycle unit which is interposed between a vehicle-exterior heat exchanger and a vehicle-interior heat exchanger and exchanges heat between respective secondary refrigerants flowing through the vehicle-exterior heat exchanger and the vehicle-interior heat exchanger. The vehicular refrigeration cycle unit is provided with a refrigeration cycle including a compressor, a condenser, an expansion valve, and an evaporator through which a primary refrigerant sequentially flows. A length of a pipe connecting the compressor and the evaporator is longer than a length of a pipe connecting the compressor and the condenser.

A vehicular air conditioning device according to the present disclosure includes the vehicular refrigeration cycle unit, the vehicle-exterior heat exchanger, and the vehicle-interior heat exchanger.

Advantageous Effects of Invention

According to the present disclosure, it is possible to provide a vehicular refrigeration cycle unit and a vehicular air conditioning device that can suppress a decrease in a heat exchange efficiency of an evaporator.

DESCRIPTION OF EMBODIMENTS

Hereinafter, a vehicular air conditioning device according to an embodiment of the present disclosure will be described with reference to the drawings.

First Embodiment

Vehicular Air Conditioning Device

A vehicular air conditioning device is a device that is installed in an electric vehicle or the like and that conditions air in a vehicle body. A difference in temperature between the inside and the outside of the vehicle body is regulated by the vehicular air conditioning device. In the present embodiment, a configuration in which the vehicular air conditioning device performs a heating operation will be described as an example.

As illustrated inFIG.1, a vehicular air conditioning device1includes a vehicular refrigeration cycle unit100, a vehicle-interior heat medium circuit20, and a vehicle-exterior heat medium circuit30.

In the drawings, among various lines (pipes) included in the vehicular refrigeration cycle unit100, the vehicle-interior heat medium circuit20, and the vehicle-exterior heat medium circuit30, lines in an open state through which a refrigerant can flow are indicated by solid lines, and lines in a closed state through which a refrigerant cannot flow are indicated by broken lines. In addition, among various valves, valves in black indicate a closed state, and valves in white indicate an open state.

Vehicular Refrigeration Cycle Unit

The vehicular refrigeration cycle unit100is a device for circulating a primary refrigerant that exchanges heat with a secondary refrigerant used for in-vehicle air conditioning. As the primary refrigerant in the present embodiment, for example, an R290 refrigerant (propane) which is a highly flammable hydrocarbon is used.

As illustrated inFIG.2, the vehicular refrigeration cycle unit100includes a casing11, a refrigeration cycle10, various lines (a suction line124, a discharge line143, a pre-expansion line136, and a post-expansion line162), and a partition wall portion17.

Casing

The casing11has a box shape, and accommodates the refrigeration cycle10, the partition wall portion17, the suction line124, the discharge line143, the pre-expansion line136, and the post-expansion line162.

Refrigeration Cycle

The refrigeration cycle10includes a plurality of devices that configure a thermodynamic cycle. The refrigeration cycle10is a refrigerant circuit in which the primary refrigerant serving as a heat medium is made to sequentially flow and circulate through the plurality of devices while being repeatedly compressed and expanded, and evaporated and condensed, so as to exchange heat with the secondary refrigerant.

The refrigeration cycle10includes an evaporator12, a compressor14, a condenser13, a receiver15, and an expansion valve16.

The evaporator12is a plate-type heat exchanger that evaporates (gasifies) the primary refrigerant by heat exchange between the primary refrigerant sequentially flowing through the refrigeration cycle10and the secondary refrigerant introduced from the outside of the vehicular refrigeration cycle unit100. The primary refrigerant in the evaporator12absorbs heat from the secondary refrigerant while simultaneously cooling the secondary refrigerant. The evaporator12is provided at a bottom surface11aof the casing11inside the casing11.

Compressor

The compressor14is a device for compressing the primary refrigerant that has absorbed heat to be gasified by passing through the evaporator12. The compressor14and the evaporator12are connected to each other by the suction line124. That is, one end of the suction line124is connected to a primary refrigerant outlet section12bof the evaporator12, and the other end of the suction line124is connected to a suction port14bof the compressor14.

The pressure of the primary refrigerant introduced into the compressor14is increased through compression by the compressor14to a predetermined pressure higher than the pressure before the compression. As a result, the temperature of the primary refrigerant becomes higher than before the compression.

The compressor14includes a compressor casing14a, a suction port14b, and a discharge port14c.

The compressor casing14ahas a tube shape and is disposed so as to extend in a gravitational direction G from the bottom surface11aof the casing11inside the casing11. The compressor14in the present embodiment is a so-called vertical compressor. A refrigerant compression mechanism is formed inside the compressor casing14a.

The suction port14bis a refrigerant inlet section for introducing a refrigerant into the compressor casing14a. The suction port14bis provided at an end portion of the compressor casing14aon a lower side in the gravitational direction G. The primary refrigerant is introduced into the compressor casing14athrough the suction port14b.

The discharge port14cis a refrigerant outlet section for discharging a refrigerant from the compressor casing14a. The discharge port14cis provided at an end portion of the compressor casing14aon an upper side in the gravitational direction G. The primary refrigerant is discharged to the outside of the compressor casing14athrough the discharge port14c. The discharge port14cis a portion of the compressor14at which the temperature becomes the highest.

Condenser

The condenser13is a plate-type heat exchanger that condenses (liquefies) the primary refrigerant by heat exchange between the primary refrigerant, which has a higher temperature and a higher pressure than before being compressed by passing through the compressor14, and the secondary refrigerant introduced from the outside of the vehicular refrigeration cycle unit100. The condenser13is provided at the bottom surface11aof the casing11inside the casing11.

The condenser13and the compressor14are connected to each other by the discharge line143. That is, one end of the discharge line143is connected to the discharge port14cof the compressor14, and the other end of the discharge line143is connected to a primary refrigerant inlet section13aof the condenser13. The primary refrigerant in the condenser13is cooled by the secondary refrigerant while increasing the temperature of the secondary refrigerant.

The primary refrigerant in a gas state introduced into the condenser13is cooled by the secondary refrigerant to enter a gas-liquid two-phase state, and then to transition into a liquid state. Accordingly, the primary refrigerant having passed through the condenser13becomes a fluid in a liquid mixed state.

The condenser13is disposed adjacent to the compressor14inside the casing11. In the present embodiment, a direction in which the condenser13is adjacent to the compressor14(the left-right direction inFIG.2) is referred to as a first adjacent direction H1, and a direction orthogonal to the first adjacent direction H1(the up-down direction inFIG.2) is referred to as a second adjacent direction H2. The first adjacent direction H1and the second adjacent direction H2are orthogonal to the gravitational direction G. Thus, a horizontal direction is defined by the first adjacent direction H1and the second adjacent direction H2.

Here, the evaporator12is adjacent to the condenser13from one side in the second adjacent direction H2. While the condenser13is adjacent to the compressor14in the first adjacent direction H1, the evaporator12is only separated from the compressor14in the horizontal direction and is not adjacent to the compressor14in both the first adjacent direction H1and the second adjacent direction H2. Thus, the distance between the compressor14and the evaporator12is longer than the distance between the compressor14and the condenser13.

Further, the discharge port14cof the compressor14in the present embodiment faces the condenser13in the first adjacent direction H1. Thus, a distance between the discharge port14cfor the primary refrigerant at the compressor14and the evaporator12is longer than a distance between the discharge port14cand the condenser13. More specifically, a length of a pipe connecting the compressor14and the evaporator12, that is, a length of the suction line124is longer than a length of a pipe connecting the compressor14and the condenser13, that is, the length of the discharge line143.

Note that “adjacent in the first adjacent direction H1” means that more than half of the size in the second adjacent direction H2of one of two objects arranged side by side inside the casing11overlaps the size in the second adjacent direction H2of the other object when viewed from the first adjacent direction H1. Further, “adjacent in the second adjacent direction H2” means that more than half of the size in the first adjacent direction H1of one of two objects arranged side by side inside the casing11overlaps the size in the first adjacent direction H1of the other object when viewed from the second adjacent direction H2.

Receiver

The receiver15is a gas-liquid separator that receives the primary refrigerant having become a fluid in a gas-liquid mixed state by passing through the condenser13, separates the primary refrigerant into a gas phase and a liquid phase, and temporarily retains the gas phase and the liquid phase. The receiver15is provided at the bottom surface11aof the casing11inside the casing11.

The receiver15and the condenser13are connected to each other by a first line135of the pre-expansion line136. That is, one end of the first line135is connected to a primary refrigerant outlet section13bof the condenser13, and the other end of the first line135is connected to a refrigerant inlet section of the receiver15.

The primary refrigerant in the gas-liquid mixed state introduced into the receiver15flows into a liquid phase portion retained inside the receiver15. A liquid part of the primary refrigerant having flowed in is added to the liquid phase, and the remaining gas part becomes bubbles, moves upward inside the receiver15, and is added to the gas phase. The primary refrigerant retained as the liquid phase inside the receiver15is discharged to the outside of the receiver15. Thus, the primary refrigerant in a liquid state is constantly supplied from the receiver15.

Expansion Valve

The expansion valve16is a device that receives the primary refrigerant having entered a liquid state by passing through the receiver15, and adiabatically expands the primary refrigerant. The expansion valve16is provided at the bottom surface11aof the casing11inside the casing11. The expansion valve16and the receiver15are connected to each other by a second line156of the pre-expansion line136. That is, one end of the second line156is connected to a refrigerant outlet section of the receiver15, and the other end of the second line156is connected to the expansion valve16.

The pressure of the primary refrigerant introduced into the expansion valve16is decreased by an expansion effect of the expansion valve16to a predetermined pressure lower than before the expansion. As a result, the temperature of the primary refrigerant becomes lower than before the expansion. Specifically, the primary refrigerant having passed through the expansion valve16becomes a fluid in a liquid state and is decreased to a temperature lower than the temperature of the secondary refrigerant that is a heat-exchange destination.

The expansion valve16and the evaporator12are connected by the post-expansion line162, and the primary refrigerant having passed through the expansion valve16is introduced into the evaporator12through the post-expansion line162. That is, one end of the post-expansion line162is connected to the expansion valve16, and the other end of the post-expansion line162is connected to a primary refrigerant inlet section12aof the evaporator12.

Partition Wall Portion

The partition wall portion17is a heat insulating member provided between the evaporator12and the condenser13inside the casing11. The thermal conductivity of the partition wall portion17is lower than the thermal conductivity of the casing11. In the present embodiment, the partition wall portion17includes a partition wall plate17awhich is a plate member standing upward in the gravitational direction G from the bottom surface11aof the casing11inside the casing11and separating the evaporator12and the condenser13from each other. That is, the longitudinal direction of the partition wall plate17acoincides with the first adjacent direction H1. Thus, heat transfer via air between the evaporator12and the condenser13is suppressed. More specifically, since the partition wall plate17aprovided at the bottom surface11ais interposed between the evaporator12and the condenser13, thermal conduction through a bottom portion of the casing11constituting the bottom surface11a, convective flow of air in the casing11, and heat radiation from the condenser13to the evaporator12are suppressed. In the present embodiment, the thermal conduction, convective flow, and heat radiation are collectively referred to as “heat transfer”. As a material constituting the partition wall plate17a, for example, rubber or resin is used. Note that the partition wall plate17may be formed of the same material as the casing11.

Vehicle-Interior Heat Medium Circuit

The vehicle-interior heat medium circuit20is a refrigerant circuit through which the secondary refrigerant having exchanged heat with the primary refrigerant in the refrigeration cycle10flows and which conditions air in the vehicle interior. For the secondary refrigerant in the present embodiment, an antifreezing liquid such as ethylene glycol is used as a liquid coolant (cooling water).

As illustrated inFIG.1, the vehicle-interior heat medium circuit20includes a heater core21a(vehicle-interior heat exchanger21), a cooler core21b(vehicle-interior heat exchanger21), a first pump22, a first valve23, a second valve24, and various lines (first heat medium line20ato seventh heat medium line20g).

The heater core21aand the cooler core21bare heat exchangers for causing indoor air inside the vehicle body C and outdoor air outside the vehicle body C to exchange heat with the secondary refrigerant. The secondary refrigerant having passed through the condenser13of the vehicular refrigeration cycle unit100is introduced into the heater core21a. In the process of introducing the secondary refrigerant from the condenser13to the heater core21a, the secondary refrigerant passes through the first pump22and the first valve23.

The first pump22is a pump that pumps the secondary refrigerant having passed through the condenser13to the heater core21a. The first heat medium line20aserving as a flow path for suctioning the secondary refrigerant into the first pump22connects the condenser13and the first pump22. That is, one end of the first heat medium line20ais connected to a secondary refrigerant outlet section13dof the condenser13, and the other end of the first heat medium line20ais connected to a refrigerant suction port of the first pump22.

The second heat medium line20bserving as a flow path for discharging the secondary refrigerant from the first pump22toward the heater core21aconnects the first pump22and the first valve23. That is, one end of the second heat medium line20bis connected to a refrigerant discharge port of the first pump22, and the other end of the second heat medium line20bis connected to the first valve23. The first valve23is a three-way valve that can change the flow path (destination) of the secondary refrigerant.

The first valve23and the heater core21aare connected by a third heat medium line20c. That is, one end of the third heat medium line20cis connected to the first valve23, and the other end of the third heat medium line20cis connected to the heater core21a.

The secondary refrigerant introduced into the heater core21ais cooled by heat exchange with the indoor air and the outdoor air introduced into the vehicle body C while increasing the temperatures of the indoor air and the outdoor air. Accordingly, the air in the vehicle body C can be heated. For example, outdoor air outside the vehicle body C introduced by a blower (not illustrated) disposed upstream of the heater core21aand the cooler core21bis used as the outdoor air.

The secondary refrigerant cooled in the heater core21ais returned to the condenser13via the second valve24. The second valve24is a three-way valve that can change the flow path (destination) of the secondary refrigerant. The first valve23and the heater core21aare connected by the fourth heat medium line20d. That is, one end of the fourth heat medium line20dis connected to a refrigerant outlet section of the heater core21a, and the other end of the fourth heat medium line20dis connected to the second valve24.

The second valve24and the condenser13are connected by a fifth heat medium line20e. That is, one end of the fifth heat medium line20eis connected to the second valve24, and the other end of the fifth heat medium line20eis connected to a secondary refrigerant inlet section13cof the condenser13.

With the configuration described above, the secondary refrigerant sequentially flows through the condenser13, the first pump22, and the heater core21a, and returns to the condenser13. By repeating this circulation, the heating operation is achieved, and an increase in temperature in the vehicle interior can be maintained.

Here, the cooler core21bis provided in the vehicle body C independently of the heater core21a. During the cooling operation, the secondary refrigerant having passed through the evaporator12is introduced into the cooler core21bso as to exchange heat between the secondary refrigerant and outdoor air. The flow of the secondary refrigerant during the cooling operation will be described below.

Vehicle-Exterior Heat Medium Circuit

The vehicle-exterior heat medium circuit30is a refrigerant circuit through which the secondary refrigerant having exchanged heat with the primary refrigerant in the refrigeration cycle10flows and which cools a battery for driving the vehicle body.

The vehicle-exterior heat medium circuit30includes a vehicle-exterior heat exchanger31, a second pump32, various valves (a third valve33and a fifth valve35), a battery cooler36, and various lines (an eighth heat medium line30ato a twelfth heat medium line30e, and a first connection line30fto a fourth connection line30i).

The vehicle-exterior heat exchanger31is a heat exchanger for exchanging heat between the outdoor air and the secondary refrigerant. A part of the secondary refrigerant having passed through the evaporator12of the vehicular refrigeration cycle unit100is introduced into the vehicle-exterior heat exchanger31via the third valve33. The remaining part of the secondary refrigerant having passed through the evaporator12is introduced into the battery cooler36via the fourth valve34.

The evaporator12is connected to the third valve33and the fourth valve34by the eighth heat medium line30a. Specifically, one end of the eighth heat medium line30ais connected to a secondary refrigerant outlet section12dof the evaporator12, and the other end of the eighth heat medium line30ais branched in two directions partway along the eighth heat medium line30aand connected to the third valve33and the fourth valve34, respectively. The third valve33and the fourth valve34are three-way valves that can change the flow path (destination) of the secondary refrigerant.

The third valve33and the vehicle-exterior heat exchanger31are connected by the ninth heat medium line30b. That is, one end of the ninth heat medium line30bis connected to the third valve33, and the other end of the ninth heat medium line30bis connected to a refrigerant inlet section of the vehicle-exterior heat exchanger31.

The secondary refrigerant introduced into the vehicle-exterior heat exchanger31through the eighth heat medium line30a, the third valve33, and the ninth heat medium line30babsorbs heat by heat exchange with the outdoor air. Accordingly, the temperature of the secondary refrigerant becomes higher than the temperature of the primary refrigerant introduced into the evaporator12, and thus the secondary refrigerant can increase the temperature of the primary refrigerant flowing through the refrigeration cycle10in the evaporator12. Outdoor air, which is a heat exchange destination of the vehicle-exterior heat exchanger31, is suctioned from the outside of the vehicle body C via a front grille F by a blower B provided on a front side inside the vehicle body C.

The second pump32is a pump that pumps the secondary refrigerant whose temperature has been increased by the vehicle-exterior heat exchanger31to the evaporator12. The secondary refrigerant having passed through the vehicle-exterior heat exchanger31passes through the fifth valve35in the process of being suctioned into the second pump32. The fifth valve35is a three-way valve that can change the flow path (destination) of the secondary refrigerant.

The fifth valve35and the vehicle-exterior heat exchanger31are connected by the tenth heat medium line30c. That is, one end of the tenth heat medium line30cis connected to the vehicle-exterior heat exchanger31, and the other end of the tenth heat medium line30cis connected to the fifth valve35.

The eleventh heat medium line30dserving as a flow path for suctioning the secondary refrigerant into the second pump32connects the fifth valve35and the second pump32. That is, one end of the eleventh heat medium line30dis connected to the fifth valve35, and the other end of the eleventh heat medium line30dis connected to the second pump32.

The second pump32and the evaporator12are connected by the twelfth heat medium line30e. That is, one end of the twelfth heat medium line30eis connected to the second pump32, and the other end of the twelfth heat medium line30eis connected to a secondary refrigerant inlet section12cof the evaporator12. Accordingly, the secondary refrigerant pumped by the second pump is introduced into the evaporator12.

With the configuration described above, the secondary refrigerant sequentially flows through the evaporator12, the vehicle-exterior heat exchanger31, and the second pump32, and returns to the evaporator12. By repeating this circulation, an increase in the temperature of the primary refrigerant circulating through the refrigeration cycle10can be maintained by heat exchange in the evaporator12.

Accordingly, the vehicular refrigeration cycle unit100is interposed between the vehicle-exterior heat exchanger31and the heater core21a(vehicle-interior heat exchanger21), and performs heat exchange between the secondary refrigerant flowing through the vehicle-exterior heat exchanger31and the secondary refrigerant flowing through the vehicle-interior heat exchanger21.

The battery cooler36is a heat exchanger for cooling a battery. The battery cooler36is provided inside the vehicle body C. The above-described remaining part of the secondary refrigerant cooled by the evaporator12and flowing through the eighth heat medium line30ais introduced into the battery cooler36via the fourth valve34. The fourth valve34and the battery cooler36are connected by a first connection line30f. That is, one end of the first connection line30fis connected to the fourth valve34, and the other end of the first connection line30fis connected to a refrigerant inlet section of the battery cooler36.

The secondary refrigerant heated by heat exchange with a battery (not illustrated) in the battery cooler36is returned to the evaporator12. The battery cooler36and the eleventh heat medium line30dare connected by the second connection line30g. Specifically, one end of the second connection line30gis connected to a refrigerant outlet section of the battery cooler36, and the other end of the second connection line30gis connected to a portion of the eleventh heat medium line30don the fifth valve35side with respect to the second pump32. Thus, the secondary refrigerant having passed through the battery cooler36joins the eleventh heat medium line30dvia the second connection line30g, and is pumped to the evaporator12again by the second pump32.

Here, the fourth valve34and the cooler core21bare connected by a sixth heat medium line20f. That is, one end of the sixth heat medium line20fis connected to the fourth valve34, and the other end of the sixth heat medium line20fis connected to a refrigerant inlet section of the heater core21a. In addition, the cooler core21band the second connection line30gare connected by the seventh heat medium line20g. That is, one end of the seventh heat medium line20gis connected to the cooler core21b, and the other end of the seventh heat medium line20gis connected to the second connection line30g. Thus, the secondary refrigerant having passed through the evaporator12during the cooling operation of the vehicular air conditioning device1can flow into the cooler core21bvia the fourth valve34.

During the heating operation, the fourth valve34causes the secondary refrigerant having flowed in from the eighth heat medium line30ato flow only to the first connection line30fwithout flowing to the sixth heat medium line20f. That is, the fourth valve34does not supply the secondary refrigerant to the cooler core21bbut supplies the secondary refrigerant only to the battery cooler36.

Further, the first valve23and the fifth valve35are connected by the third connection line30h. That is, one end of the third connection line30his connected to the first valve23, and the other end of the third connection line30his connected to the fifth valve35.

During the heating operation, the first valve23causes the secondary refrigerant having flowed in from the second heat medium line20bto flow only to the third heat medium line20cwithout flowing to the third connection line30h. The fifth valve35causes the secondary refrigerant having flowed in from the tenth heat medium line30cto flow only to the eleventh heat medium line30dwithout flowing to the third connection line30h.

In addition, the second valve24and the third valve33are connected by the fourth connection line30i. That is, one end of the fourth connection line30iis connected to the second valve24, and the other end of the fourth connection line30iis connected to the third valve33.

During the heating operation, the second valve24causes the secondary refrigerant having flowed in from the fourth heat medium line20dto flow only to the fifth heat medium line20ewithout flowing to the fourth connection line30i. The third valve33causes the secondary refrigerant having flowed in from the eighth heat medium line30ato flow only to the ninth heat medium line30bwithout flowing to the fourth connection line30i.

Operational Effects

In the vehicular refrigeration cycle unit100according to the above-described embodiment, for the compressor14, the evaporator12and the condenser13constituting the refrigeration cycle10, a distance between the compressor14and the evaporator12is longer than a distance between the compressor14and the condenser13, and thus the amount of heat such as radiant heat transferred from the compressor14to the evaporator12is smaller than the amount of heat transferred to the condenser13. Thus, an increase in the temperature of the evaporator12caused by the compressor14can be suppressed more than an increase in the temperature of the condenser13caused by the compressor14. Accordingly, a decrease in the heat exchange efficiency between the primary refrigerant and the secondary refrigerant in the evaporator12can be suppressed.

In the vehicular refrigeration cycle unit100according to the above-described embodiment, since the distance between the discharge port14cfor the primary refrigerant at the compressor14and the evaporator12is longer than the distance between the discharge port14cand the condenser13, the amount of heat such as radiant heat transferred from discharge port14cof the compressor14to the evaporator12is smaller than the amount of heat of radiant heat transferred to the condenser13. As a result, the same operational effects as described above can be achieved.

In the vehicular refrigeration cycle unit100according to the above-described embodiment, since the length of the pipe connecting the compressor14and the evaporator12is longer than the length of the pipe connecting the compressor14and the condenser13, heat is less likely to be transferred from the compressor14to the evaporator12through these pipes. As a result, the same operational effects as described above can be achieved.

The vehicular refrigeration cycle unit100according to the above-described embodiment includes the partition wall portion17separating the condenser13and the evaporator12from each other between the condenser13and the evaporator12, heat transfer from the condenser13to the evaporator12can be suppressed by the partition wall portion17. Thus, an increase in the temperature of the evaporator caused by the condenser can be suppressed.

In addition, since the partition wall portion17of the vehicular refrigeration cycle unit100according to the above-described embodiment is a plate member, heat transfer from the condenser13to the evaporator12can be suppressed with a simple configuration of the plate member.

Second Embodiment

A vehicular air conditioning device1according to a second embodiment of the present disclosure will be described below. The vehicular refrigeration cycle unit100described in the second embodiment is different from the vehicular refrigeration cycle unit100of the first embodiment in the configuration of the partition wall portion17. The same components as those in the first embodiment are denoted by the same reference signs, and detailed descriptions thereof are omitted.

Partition Wall Portion

As illustrated inFIG.3, the partition wall portion17is a heat insulating member provided between the evaporator12and the condenser13inside the casing11. The partition wall portion17in the present embodiment includes an accommodation body17bthat accommodates only the compressor14and the condenser13out of the compressor14, the condenser13, and the evaporator12constituting the refrigeration cycle10. That is, the casing11and the accommodation body17bare in a nested relationship. Heat transfer between the evaporator12and the condenser13is suppressed by a partition wall of the accommodation body17b. As a material constituting the accommodation body17b, for example, rubber or resin is used.

Operational Effects

In the vehicular refrigeration cycle unit100according to the above-described embodiment, heat such as radiant heat generated from the compressor14and the condenser13can be retained in the accommodation body17b. Thus, the amount of heat transferred from the compressor14to the evaporator12is smaller than the amount of heat transferred to the condenser13. Therefore, the same operational effects as in the first embodiment can be achieved.

Third Embodiment

A vehicular air conditioning device1according to a third embodiment of the present disclosure will be described below. The vehicular refrigeration cycle unit100described in the second embodiment is different from the vehicular refrigeration cycle unit100of the first embodiment in the positional relationship between (arrangement of) the evaporator12, the compressor14, and the condenser13in the casing11. The same components as those in the first embodiment are denoted by the same reference signs, and detailed descriptions thereof are omitted.

Condenser

As illustrated inFIG.4, the condenser13is disposed adjacent to the compressor14inside the casing11. In the present embodiment, a direction in which the condenser13is adjacent to the compressor14(the up-down direction inFIG.4) is referred to as a second adjacent direction H2, and a direction orthogonal to the second adjacent direction H2(the left-right direction inFIG.4) is referred to as a first adjacent direction H1. The first adjacent direction H1and the second adjacent direction H2are orthogonal to a weight direction. That is, a horizontal direction is defined by the first adjacent direction H1and the second adjacent direction H2.

Here, the evaporator12is adjacent to the condenser13from one side in the second adjacent direction H2, and the compressor14is adjacent to the condenser13from the other side in the second adjacent direction H2. That is, the condenser13is disposed between the compressor14and the evaporator12. Thus, the distance between the compressor14and the evaporator12is longer than the distance between the compressor14and the condenser13.

Further, the discharge port14cof the compressor14in the present embodiment faces one side in the first adjacent direction H1, and the distance between the discharge port14cand the evaporator12is longer than the distance between the discharge port14cand the condenser13. More specifically, the length of the pipe connecting the compressor14and the evaporator12, that is, the length of the suction line124is longer than the length of the pipe connecting the compressor14and the condenser13, that is, the length of the discharge line143.

Operational Effects

In the vehicular refrigeration cycle unit100according to the above-described embodiment, since the condenser13is disposed between the compressor14and the evaporator12, the amount of heat such as radiant heat transferred from the compressor14to the evaporator12is smaller than the amount of heat transferred to the condenser13. Therefore, the same operational effects as in the first embodiment can be achieved.

Fourth Embodiment

A vehicular air conditioning device1according to a fourth embodiment of the present disclosure will be described below. The vehicular refrigeration cycle unit100described in the fourth embodiment is different from the vehicular refrigeration cycle unit100of the third embodiment in the configuration of the partition wall portion17. The same components as those in the third embodiment are denoted by the same reference signs, and detailed descriptions thereof are omitted.

Partition Wall Portion

As illustrated inFIG.5, the partition wall portion17is a heat insulating member provided between the evaporator12and the condenser13inside the casing11. The partition wall portion17in the present embodiment includes the accommodation body17bthat accommodates only the compressor14and the condenser13out of the compressor14, the condenser13, and the evaporator12constituting the refrigeration cycle10. That is, the casing11and the accommodation body17bare in a nested relationship. Direct heat transfer via air between the evaporator12and the condenser13is suppressed by a partition wall of the accommodation body17b.

Operational Effects

In the vehicular refrigeration cycle unit100according to the above-described embodiment, heat such as radiant heat generated from the compressor14and the condenser13can be retained in the accommodation body17b. Thus, the amount of heat transferred from the compressor14to the evaporator12is smaller than the amount of heat transferred to the condenser13. Therefore, the same operational effects as in the first embodiment can be achieved.

Fifth Embodiment

A vehicular air conditioning device1according to a fifth embodiment of the present disclosure will be described below. The vehicular refrigeration cycle unit100described in the fifth embodiment is different from the vehicular refrigeration cycle unit100of the first embodiment in the arrangement of the compressor14. The same components as those in the first embodiment are denoted by the same reference signs, and detailed descriptions thereof are omitted.

Compressor

As illustrated inFIG.6, the compressor14includes the compressor casing14a, the suction port14b, and the discharge port14c.

The compressor casing14ahas a tube shape and is disposed so as to extend in the second adjacent direction H2at the bottom surface11aof the casing11inside the casing11. The compressor14in the present embodiment is a so-called vertical compressor. A refrigerant compression mechanism is formed inside the compressor casing14a.

The suction port14bis a refrigerant inlet section for introducing a refrigerant into the compressor casing14a. The suction port14bis provided at an end portion of the compressor casing14aon one side in the second adjacent direction H2. That is, the suction port14bis provided at the compressor casing14aon a side of the condenser13out of the evaporator12and the condenser13. The primary refrigerant is introduced into the compressor casing14athrough the suction port14b. The suction port14bis a portion of the compressor14at which the temperature becomes the lowest.

The discharge port14cis a refrigerant outlet section for discharging a refrigerant from the compressor casing14a. The discharge port14cis provided at an end portion of the compressor casing14aon the other side in the second adjacent direction H2. That is, the discharge port14cis provided at the compressor casing14aon a side of the evaporator12out of the evaporator12and the condenser13. The primary refrigerant is discharged to the outside of the compressor casing14athrough the discharge port14c. The discharge port14cis a portion of the compressor14at which temperature becomes the highest. Thus, the compressor casing14ahas a temperature distribution in which temperature gradually increases from a side of the suction port14bto a side of the discharge port14c.

Operational Effects

In the vehicular refrigeration cycle unit100according to the above-described embodiment, the suction port14bis disposed at the compressor casing14aon a side of the condenser13out of the evaporator12and the condenser13and the discharge port14cis provided at the compressor casing14aon a side of the evaporator12, and thus the amount of heat such as radiant heat transferred from the compressor14to the evaporator12is smaller than the amount of heat transferred to the condenser13. Therefore, the same operational effects as in the first embodiment can be achieved.

OTHER EMBODIMENTS

The embodiments of the present disclosure have been described above in detail with reference to the drawings. However, specific configurations are not limited to the configurations of each of the embodiments. Any configuration can be added, omitted, substituted, or otherwise modified, as long as such addition, omission, substitution, or modification does not depart from the scope of the present disclosure. Furthermore, the present disclosure is not to be considered as being limited by the embodiments and is only limited by the scope of the appended claims.

In the above-described embodiments, the configuration in which the vehicular air conditioning device1performs the heating operation has been described as an example. However, the configuration is not limited to the heating operation, and the vehicular refrigeration cycle unit100may employ a configuration similar to the configuration of the above-described embodiments even in the case where cooling operation is performed.

Hereinafter, configurations of the vehicle-interior heat medium circuit20and the vehicle-exterior heat medium circuit30during the cooling operation will be described with reference toFIG.7.

The first pump22pumps the secondary refrigerant condensed by the condenser13to the vehicle-exterior heat exchanger31. The first heat medium line20aserving as a flow path for suctioning the secondary refrigerant into the first pump22connects the condenser13and the first pump22.

The second heat medium line20bserving as a flow path for discharging the secondary refrigerant from the first pump22toward the vehicle-exterior heat exchanger31connects the first pump22and the first valve23. Here, the first valve23causes the secondary refrigerant discharged from the first pump22to flow to the fourth connection line30iwithout flowing to the third heat medium line20c. The secondary refrigerant having flowed into the fourth connection line30iflows into the third valve33.

Here, the third valve33causes the secondary refrigerant having flowed in from the fourth connection line30ito flow to the tenth heat medium line30cwithout flowing to the eleventh heat medium line30d. The secondary refrigerant having flowed into the tenth heat medium line30cflows into the vehicle-exterior heat exchanger31.

The secondary refrigerant having passed through the vehicle-exterior heat exchanger31flows into the fourth valve34via the ninth heat medium line30b. Thus, a flow direction of the secondary refrigerant flowing through the tenth heat medium line30c, the vehicle-exterior heat exchanger31, and the ninth heat medium line30bduring the cooling operation of the vehicular air conditioning device1is opposite to a flow direction of the secondary refrigerant during the heating operation.

Here, the fourth valve34causes the secondary refrigerant having flowed in from the ninth heat medium line30bto flow to the third connection line30hwithout flowing to the eighth heat medium line30a. The secondary refrigerant having flowed into the third connection line30hflows into the second valve24.

Here, the second valve24causes the secondary refrigerant having flowed in from the third connection line30hto flow to the fifth heat medium line20ewithout flowing to the fourth heat medium line20d. The secondary refrigerant having flowed into the fifth heat medium line20eflows into the condenser13.

With the configuration described above, the secondary refrigerant sequentially flows through the condenser13, the first pump22, and the vehicle-exterior heat exchanger31, and returns to the condenser13. By repeating this circulation, the primary refrigerant circulating through the refrigeration cycle10can be continuously cooled by heat exchange in the condenser13.

The second pump32pumps the secondary refrigerant cooled by the evaporator12to the cooler core21b. The secondary refrigerant having passed through the evaporator12is introduced into the eighth heat medium line30aand then into the fifth valve35by the suction force of the pump. Here, the fifth valve35causes the secondary refrigerant having flowed in from the eighth heat medium line30ato flow to both the sixth heat medium line20fand the first connection line30f.

The secondary refrigerant having flowed into the sixth heat medium line20fflows into the cooler core21b. The secondary refrigerant having completed heat exchange in the cooler core21bflows into the seventh heat medium line20g, and then flows into the second connection line30g. The secondary refrigerant having flowed into the second connection line30gflows into the eleventh heat medium line30d, and returns to the evaporator12via the second pump32and the twelfth heat medium line30e.

The secondary refrigerant having flowed into the first connection line30fflows into the battery cooler36. Thus, the battery cooler36exchanges heat with (is cooled by) the secondary refrigerant during both the heating operation and the cooling operation of the vehicular air conditioning device1. The secondary refrigerant having completed heat exchange in the battery cooler36flows into the second connection line30g. The secondary refrigerant having flowed into the second connection line30gflows into the eleventh heat medium line30d, and returns to the evaporator12via the second pump32and the twelfth heat medium line30e.

With the configuration described above, the secondary refrigerant sequentially flows through the evaporator12, the cooler core21b, and the second pump32, and returns to the evaporator12. By repeating this circulation, the cooling operation is achieved, and the vehicle interior can be continuously cooled.

The partition wall plate17aincluded in the partition wall portion17in the above-described embodiments is not limited to the configurations of the first embodiment and the third embodiment. For example, as illustrated inFIG.8, the partition wall plate17amay be disposed so as to separate the condenser13and the evaporator12from each other and to separate the expansion valve16and the evaporator12from each other in the casing11. Accordingly, heat transfer to the evaporator12can be further suppressed.

In the above-described embodiments, an example in which an R290 refrigerant is used as the primary refrigerant and ethylene glycol is used as the secondary refrigerant has been described, but other refrigerants may be used as the primary refrigerant and the secondary refrigerant.

The vehicle-exterior heat medium circuit30in the above-described embodiments may further include a traction motor cooler (not illustrated) that is a heat exchanger for cooling a traction motor, and an inverter cooler (not illustrated) that is a heat exchanger for cooling an inverter (power converter). In that case, the secondary refrigerant having passed through the vehicle-exterior heat exchanger31is introduced into each of the traction motor cooler and the inverter cooler as cooling water for cooling the traction motor and the inverter through pipes (not illustrated) that connect the vehicle-exterior heat exchanger31to the traction motor cooler and the inverter cooler. Furthermore, the secondary refrigerant heated by heat exchange in the traction motor cooler and the inverter cooler may flow into the eleventh heat medium line30dthrough a pipe, similarly to the secondary refrigerant flowing through the second connection line30gfrom the battery cooler36toward the eleventh heat medium line30d.

In addition, the vehicular refrigeration cycle unit100according to the above-described embodiments may further include a bracket that includes an upper surface facing upward in the gravitational direction G. The bracket fixes the evaporator12, the compressor14, and the condenser13to the upper surface in a state of being interposed between the refrigeration cycle10and the bottom surface11aof the casing11. In that case, for example, the bracket fixes the refrigeration cycle10to the upper surface in a state of being fixed to an inner wall surface of a front compartment or the like outside the vehicle interior. Thus, the refrigeration cycle10may be provided at the bottom surface11aof the casing11via the bracket. In that case, the thermal conductivity of the partition wall portion17is lower than the thermal conductivity of the bracket.

Supplementary Notes

The vehicular refrigeration cycle unit and the vehicular air conditioning device according to the above-described embodiments are understood as follows, for example.

(1) A vehicular refrigeration cycle unit100according to a first aspect is a vehicular refrigeration cycle unit100which is interposed between a vehicle-exterior heat exchanger31and a vehicle-interior heat exchanger21and exchanges heat between respective secondary refrigerants flowing through the vehicle-exterior heat exchanger31and the vehicle-interior heat exchanger21. The vehicular refrigeration cycle unit100is provided with a refrigeration cycle10including a compressor14, a condenser13, an expansion valve16, and an evaporator12through which a primary refrigerant sequentially flows. A distance between the compressor14and the evaporator12is longer than a distance between the compressor14and the condenser13.

Accordingly, the amount of heat such as radiant heat transferred from the compressor14to the evaporator12becomes smaller than the amount of heat transferred to the condenser13.

(2) A vehicular refrigeration cycle unit100according to a second aspect is a vehicular refrigeration cycle unit100which is interposed between a vehicle-exterior heat exchanger31and a vehicle-interior heat exchanger21and exchanges heat between respective secondary refrigerants flowing through the vehicle-exterior heat exchanger31and the vehicle-interior heat exchanger21. The vehicular refrigeration cycle unit100is provided with a refrigeration cycle10including a compressor14, a condenser13, an expansion valve16, and an evaporator12through which a primary refrigerant sequentially flows. A distance between a discharge port14cfor the primary refrigerant at the compressor14and the evaporator12is longer than a distance between the discharge port14cand the condenser13.

Thus, the amount of heat such as radiant heat transferred from the discharge port14cof the compressor14to the evaporator12becomes smaller than the amount of radiant heat transferred to the condenser13.

(3) A vehicular refrigeration cycle unit100according to a third aspect is a vehicular refrigeration cycle unit100which is interposed between a vehicle-exterior heat exchanger31and a vehicle-interior heat exchanger21and exchanges heat between respective secondary refrigerants flowing through the vehicle-exterior heat exchanger31and the vehicle-interior heat exchanger21. The vehicular refrigeration cycle unit100is provided with a refrigeration cycle10including a compressor14, a condenser13, an expansion valve16, and an evaporator12through which a primary refrigerant sequentially flows. A length of a pipe connecting the compressor14and the evaporator12is longer than a length of a pipe connecting the compressor14and the condenser13.

Thus, heat is less likely to be transferred from the compressor14to the evaporator12through these pipes.

(4) A vehicular refrigeration cycle unit100according to a fourth aspect is the vehicular refrigeration cycle unit100according to any one of (1) to (3), wherein the condenser13may be disposed between the compressor14and the evaporator12.

Accordingly, the amount of heat such as radiant heat transferred from the compressor14to the evaporator12becomes smaller than the amount of heat transferred to the condenser13.

(5) A vehicular refrigeration cycle unit100according to a fifth aspect is the vehicular refrigeration cycle unit100according to any one of (1) to (3), wherein a partition wall portion17separating the condenser13and the evaporator12may be further provided between the condenser13and the evaporator12.

Accordingly, heat transfer from the condenser13to the evaporator12can be suppressed by the partition wall portion17.

(6) A vehicular refrigeration cycle unit100according to a sixth aspect is the vehicular refrigeration cycle unit100according to (5), wherein the partition wall portion17may include a partition wall plate17awhich is a plate member.

Accordingly, heat transfer from the condenser13to the evaporator12can be suppressed with a simple configuration of the plate member.

(7) A vehicular refrigeration cycle unit100according to a seventh aspect is the vehicular refrigeration cycle unit100according to (5), wherein the partition wall portion17may include an accommodation body17bthat accommodates only the compressor14and the condenser13out of the compressor14, the condenser13, and the evaporator12.

Accordingly, heat such as radiant heat generated from the compressor14and the condenser13can be retained in the accommodation body17b.

(8) A vehicular air conditioning device1according to an eighth aspect includes the vehicular refrigeration cycle unit100according to any one of (1) to (7), the vehicle-exterior heat exchanger31, and the vehicle-interior heat exchanger21.

INDUSTRIAL APPLICABILITY

According to the present disclosure, it is possible to provide a vehicular refrigeration cycle unit and a vehicular air conditioning device that can suppress a decrease in a heat exchange efficiency of an evaporator.

REFERENCE SIGNS LIST