DE102007028252B4 - Refrigerant cycle device with ejector - Google Patents

Abstract

A refrigerant cycle device comprising: a compressor (12) that sucks and compresses a refrigerant; a radiator (13) for cooling the high pressure hot gas refrigerant discharged from the compressor; an ejector (14) having a nozzle portion (14a) for decompressing and expanding the refrigerant downstream of the radiator, a refrigerant suction port (14c) for sucking the refrigerant through a high - speed flow of the refrigerant discharged from the nozzle portion, and a pressure increasing portion (14b) for mixing and pressurizing the refrigerant having ejected at high speed refrigerant and the refrigerant sucked through the refrigerant suction port; a first evaporator (15) for vaporizing the refrigerant flowing out of the ejector; a first passage portion (17, 36) for guiding the refrigerant to the refrigerant suction port; a throttle unit (18) disposed in the first passage section and decompressing the refrigerant flowing in the first passage section; a second evaporator (19) disposed in the first passage portion in a refrigerant flow downstream of the throttle unit for evaporating the refrigerant; a bypass passage portion (23) for guiding the hot gas refrigerant discharged from the compressor into the second evaporator; a bypass opening / closing unit (24) provided in the bypass passage portion for opening and closing the bypass passage portion, the bypass opening / closing unit having a throttle opening degree when opened; a second passage portion (25) branching from the bypass passage portion in a refrigerant flow downstream of the bypass opening / closing unit, the hot gas refrigerant flowing in the bypass passage portion through the second passage portion to the first evaporator; and a first flow control unit (26a, 26b, 26c) provided in the second passage section for preventing a flow of refrigerant from one side of the first evaporator to a side of the second evaporator through the second passage section.

Description

FIELD OF THE INVENTION

The present invention relates to a refrigerant cycle device having an ejector that functions as a refrigerant decompressing device and a refrigerant circulating device.

BACKGROUND OF THE INVENTION

The JP-A-2006-118849 suggests a vapor compression refrigerant cycle device. This vapor compression type refrigerant cycle device is constructed such that an ejector is used as refrigerant decompressing means and refrigerant circulating means in a refrigerant cycle, and a plurality of evaporators (eg, a first evaporator, a second evaporator) are disposed downstream and on the refrigerant suction side of this ejector. The vapor compression type refrigerant cycle device is provided with an ejector blocking mechanism that opens and closes a refrigerant upstream side of the ejector; a bypass passage that connects a refrigerant discharge side of a compressor and a refrigerant inlet side of the second evaporator; and a bypass lock mechanism that opens and closes this bypass passage.

In a case where frosting occurs in an evaporator in a case where the refrigeration cycle is in operation, the ejector blocking mechanism is closed and the bypass lock mechanism is opened so that a high-temperature refrigerant (hot gas) discharged from the compressor flows from the second evaporator through the ejector to the first evaporator can. Thus, the evaporators can be easily defrosted by taking the above measure.

However, the above technique involves a problem. That is, during defrosting of the evaporators, the ejector develops resistance to the flowing refrigerant, and therefore, the refrigerant pressure at the second evaporator becomes higher than the refrigerant pressure at the first evaporator. As a result, the refrigerant temperature at the second evaporator is increased. In this case, although defrosting on the second evaporator is performed more effectively than on the first evaporator, the temperature unnecessarily tends to increase on the second evaporator until the defrosting of the first evaporator is completed, thereby reducing a cooling rate in a cooling operation after the defrosting operation.

SUMMARY OF THE INVENTION

In consideration of the above problems, an object of the present invention is to provide a refrigerant cycle device which can effectively reduce a difference between a defrosting operation of a first evaporator and a defrosting operation of a second evaporator.

It is another object of the present invention to provide a refrigerant cycle device in which the refrigerant temperatures of first and second evaporators during a defrosting operation of the first and second evaporators can be made more uniform.

It is still another object of the present invention to provide a refrigerant cycle device that can shorten a defrosting time of an evaporator.

It is still another object of the present invention to provide a refrigerant cycle device which can increase a cooling rate in a cooling operation after a defrosting operation.

According to an example of the present invention, a refrigerant cycle device includes a compressor that sucks and compresses a refrigerant; a radiator arranged to cool the high-pressure hot gas refrigerant discharged from the compressor, an ejector having a nozzle portion for decompressing and expanding the refrigerant downstream of the radiator, a refrigerant suction port for sucking a refrigerant by a high-speed flow of the refrigerant ejected from the nozzle portion, and a refrigerant Pressure increasing section for mixing and pressurizing the high-velocity discharged refrigerant and the refrigerant sucked through the refrigerant suction port; a first evaporator for vaporizing the refrigerant flowing out of the ejector; a first passage portion for guiding the refrigerant to the refrigerant suction port; a throttle unit disposed in the first passage portion and decompressing the refrigerant flowing in the first passage portion; a second evaporator disposed in the first passage portion in a refrigerant flow downstream of the throttle unit to evaporate the refrigerant; a bypass passage portion for guiding the hot gas refrigerant discharged from the compressor into the second evaporator; a bypass opening / closing unit provided in the bypass passage section to open and close the bypass passage section, wherein the bypass opening / closing unit has a bypass opening / closing unit Throttle opening degree when open; a second passage portion branching from the bypass passage portion in a refrigerant flow downstream of the bypass opening / closing unit, the hot gas refrigerant flowing in the bypass passage portion through the second passage portion to the first evaporator; and a first flow control unit provided in the second passage portion for preventing a flow of refrigerant from one side of the first evaporator through the second passage portion to a side of the second evaporator.

Accordingly, when the bypass opening / closing unit is closed, the refrigerant discharged from the compressor flows through the radiator and flows into the first evaporator through the ejector while a part of the refrigerant flows into the second evaporator through the first passage portion. Therefore, in the refrigerant cycle device, the first and second evaporators have a cooling capacity (cooling function), so that a cooling mode can be performed. In the cooling mode of the refrigerant cycle device, the surfaces of the first and second evaporators may be frozen. In this case, the bypass opening / closing unit is opened so that defrosting of the first and second evaporators can be performed. When the bypass opening / closing unit is opened, the hot gas refrigerant discharged from the compressor flows into the bypass passage portion and the second passage portion branched from the bypass passage portion. Accordingly, it is possible to directly introduce the hot gas refrigerant into both the first evaporator and the second evaporator, whereby defrosting of the first and second evaporators can be performed. As a result, it is possible to effectively reduce a difference between a defrosting operation of a first evaporator and a defrosting operation of a second evaporator. Therefore, the refrigerant temperatures of the first and second evaporators can be made more uniform even during the defrosting operation.

For example, the first passage portion may be a branch passage that branches in a refrigerant flow from the radiator from an upstream side of the nozzle portion of the ejector to guide the refrigerant from the radiator to the refrigerant suction port of the ejector. Alternatively, the refrigerant cycle device may be provided with a gas-liquid separator that separates the refrigerant discharged from the first evaporator into a vapor refrigerant and a liquid refrigerant, collects liquid refrigerant therein, and directs the vapor refrigerant to a refrigerant suction side of the compressor. In this case, the first passage portion is a connection passage connecting a liquid refrigerant outlet portion of the gas-liquid separator with the refrigerant suction port of the ejector.

In the refrigerant cycle device, the first flow control unit may be a check valve arranged to allow only a refrigerant flow from the bypass passage portion through the second passage portion to the first evaporator. Alternatively, the first flow control unit may be a switching valve arranged to open and close the second passage portion. In this case, the switching valve is opened when the bypass opening / closing unit is opened, and is closed when the bypass opening / closing unit is closed.

Alternatively, the first flow control unit may be a flow adjusting valve arranged to be brought into a closed state and regulate a flow amount of the refrigerant in accordance with its valve opening degree which is adjustable. In this case, the flow adjusting valve is brought into the closed state when the bypass opening / closing unit is closed. On the other hand, when the bypass opening / closing unit is opened, the flow adjusting valve increases its valve opening degree more when a refrigerant temperature detected by an inlet side temperature detector of the first evaporator is lower than a refrigerant temperature detected by an outlet side temperature detector of the second evaporator, and the flow adjusting valve decreases its valve opening degree more the refrigerant temperature detected by the inlet side temperature detector of the first evaporator is higher than the refrigerant temperature detected by the outlet side temperature detector of the second evaporator.

Further, the refrigerant cycle device may be provided with a third passage portion branched from the first passage portion in a refrigerant flow from the second evaporator at a position downstream of the second evaporator to guide the refrigerant flow from the second evaporator to the first evaporator, and a second flow control unit. which is arranged in the third passage portion to prevent a refrigerant flow from the first evaporator to the second evaporator through the third passage portion. In this case, the second flow control unit may be a check valve arranged to allow only a refrigerant flow from the second evaporator to the first evaporator through the third passage portion may be or may be a switching valve arranged to open and close the third passage portion be a flow adjustment valve, which is arranged to be brought into a closed state and to regulate a flow amount of a refrigerant in accordance with its valve opening degree which is adjustable.

In addition, the refrigerant cycle device may be provided with a passage opening / closing unit arranged to open and close a refrigerant passage connected to a refrigerant inlet or a refrigerant outlet of the radiator, and the passage opening / closing unit may be closed when the bypass opening / closing unit is opened.

According to another example of the present invention, a refrigerant cycle device includes a compressor that sucks and compresses a refrigerant; a radiator arranged to cool a high pressure hot gas refrigerant discharged from the compressor; an ejector having a nozzle portion for decompressing and expanding the refrigerant downstream of the radiator, and a refrigerant suction port for sucking the refrigerant by a high-speed flow of the refrigerant ejected from the nozzle portion; a first evaporator for vaporizing the refrigerant flowing out of the ejector; a branch passage portion branched from an upstream side of the nozzle portion and connected to the refrigerant suction port of the ejector pump; a throttle unit disposed in the branch passage portion and decompressing the refrigerant flowing in the branch passage portion; a second evaporator disposed in the branch passage portion in a refrigerant flow downstream of the throttle unit; a bypass passage portion for guiding the hot gas refrigerant discharged from the compressor into the second evaporator; and a bypass opening / closing unit disposed in the bypass passage section for opening and closing the bypass passage section. In the refrigerant cycle device, the first evaporator and the second evaporator are constructed such that a flow resistance of the refrigerant flowing in the second evaporator is larger than that of the refrigerant flowing in the first evaporator.

In this refrigerant cycle device, during a defrosting operation of the first and second evaporators, the hot gas refrigerant discharged from the compressor can flow through the bypass passage portion to the second evaporator, the ejector, and the first evaporator in this order. In this example of the present invention, since the flow resistance of the refrigerant flowing in the second evaporator is larger than that of the refrigerant flowing in the first evaporator, the pressure loss in the second evaporator can be made large, whereby the average temperature of the refrigerant flowing through the second evaporator during the defrosting operation is increased. As a result, it is possible to shorten the defrosting time and to increase a cooling speed in a cooling process after the defrosting operation.

For example, the first evaporator includes a plurality of first tubes in which the refrigerant flows, and the second evaporator includes a plurality of second tubes in which the refrigerant flows. In this case, each first pipe and every second pipe may be of an identical channel sectional area therein, while the second pipes of the second evaporator have a pipe number smaller than that of the first pipes of the first evaporator. Alternatively, the first tubes of the first evaporator and the second tubes of the second evaporator may be of identical tube length, while all the second tubes of the second evaporator have a channel cross-sectional area therein smaller than that of all first tubes of the first evaporator. Alternatively, all the first tubes of the first evaporator and all the second tubes of the second evaporator may have an identical channel cross-sectional area therein, while all the second tubes of the second evaporator have a tube length larger than those of the first tubes of the first evaporator. Alternatively, all the first tubes of the first evaporator and all the second tubes of the second evaporator may have an identical channel cross-sectional area therein, while the second tubes of the second evaporator have grooved channels therein and the second tubes of the first evaporator have shallow channels therein.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments when taken in conjunction with the accompanying drawings. Show:

1 a schematic representation of a refrigerant cycle device in a cooling mode according to a first embodiment of the present invention;

2 a schematic representation of the refrigerant cycle device in a defrosting mode according to the first embodiment;

3 FIG. 16 is a graph showing a relationship between a refrigerant pressure, a refrigerant temperature, and an enthalpy in a refrigerant cycle operation according to the first embodiment; FIG.

4 FIG. 14 is a graph showing a relationship between a refrigerant pressure and an enthalpy in a refrigerant cycle according to the first embodiment; FIG.

5 a diagram of a time required for a defrosting operation and a time required for a cooling process of a refrigerant cycle operation in the first embodiment and in a comparative example;

6 a schematic representation of a refrigerant cycle device in a cooling mode according to a second embodiment of the present invention;

7 a schematic representation of the refrigerant cycle device in a defrosting mode according to the second embodiment;

8th a schematic representation of a refrigerant cycle device in a cooling mode according to a third embodiment of the present invention;

9 a schematic representation of the refrigerant cycle device in a defrosting mode according to the third embodiment;

10 FIG. 15 is a graph showing a relationship between an opening degree of a flow adjusting valve and a refrigerant temperature according to the third embodiment; FIG.

11 a schematic representation of a refrigerant cycle device in a cooling mode according to a fourth embodiment of the present invention;

12 a schematic representation of the refrigerant cycle device in a defrosting mode according to the fourth embodiment;

13 a schematic representation of a refrigerant cycle device in a cooling mode according to a fifth embodiment of the present invention;

14 a schematic representation of the refrigerant cycle device in a defrosting mode according to the fifth embodiment;

15 a schematic representation of a refrigerant cycle device according to a sixth embodiment of the present invention;

16A a schematic front view of a first evaporator and 16B a schematic front view of a second evaporator according to the sixth embodiment;

17 FIG. 16 is a graph showing a relationship between a refrigerant pressure and an enthalpy during a defrosting mode in a refrigerant cycle according to the sixth embodiment; FIG.

18A and 18B Charts of a defrosting time ratio at an outside air temperature (TAM) of 35 ° C and an outside air temperature (TAM) of 0 ° C in a case where the flow resistance of the refrigerant is identical, according to the sixth embodiment;

19A a schematic front view of a first evaporator and

19B a schematic front view of a second evaporator according to a seventh embodiment of the present invention;

20A a schematic front view of a first evaporator and 20B a schematic front view of a second evaporator according to an eighth embodiment of the present invention; and

21 a schematic representation of a refrigerant cycle device according to a ninth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(First embodiment)

A first embodiment of the present invention will now be described with reference to FIG 1 to 5 described.

1 FIG. 16 shows an example in which a vapor compression refrigerant cycle device. FIG 10 of the first embodiment is typically used for a refrigerant circuit of an air conditioner for vehicles. The refrigerant cycle device 10 is with a refrigerant circulation channel 11 provided and a compressor 12 that sucks and compresses a refrigerant is in the refrigerant circulation passage 11 arranged.

The compressor 12 is driven in rotation by a vehicle engine, not shown, by a belt or the like. For the compressor 12 For example, a variable displacement compressor whose refrigerant discharge capacity can be adjusted by changing an output capacity can be used. An output capacity of the compressor 12 issued Refrigerant is equivalent to a refrigerant discharge amount per rotation. The discharge capacity can be changed by changing a capacity for sucking the refrigerant.

A swash plate type compressor can be used as a variable displacement compressor 12 to be used. For example, the swash plate type compressor may be configured to change the capacity for sucking the refrigerant by changing the angle of a swash plate to change a piston stroke. The angle of the swash plate is controlled by varying the pressure (control pressure) in a swash plate chamber from the outside electrical. This control can be performed by an electromagnetic pressure control device (not shown) constituting a shift control mechanism.

A cooler 13 is downstream of the compressor in terms of refrigerant flow 12 arranged. The cooler 13 exchanges heat between that of the compressor 12 discharged high-pressure refrigerant and by a cooling fan sent outside air (ie, air outside the vehicle compartment) off. This cools the radiator 13 that from the compressor 12 output high-pressure refrigerant.

An ejector pump 14 is downstream of the radiator with respect to the refrigerant flow 13 arranged. This ejector pump 14 has a nozzle section 14a as a decompression device for reducing the pressure of the refrigerant. At the same time the ejector pump 14 is used as a kinetic vacuum pump that receives a fluid by a suction due to a high-speed flow of the nozzle portion 14a discharged refrigerant promotes.

The ejector pump 14 contains the nozzle section 14a and a suction port (refrigerant suction port) 14c , The nozzle section 14a reduces the channel area of the cooler 13 flowing high-pressure refrigerant so as to decompress the high-pressure refrigerant and expand entendropisch. The refrigerant suction port 14c is provided so as to communicate with the refrigerant jet hole of the nozzle portion 14a communicates and the refrigerant from a later-described second evaporator 19 sucks.

Further, regarding the refrigerant flow on a downstream side of the nozzle portion 14a and the refrigerant suction port 14c a diffuser section 14b provided with a pressure increasing portion in the ejector 14 forms. This diffuser section 14b is formed in such a shape that the area of the refrigerant channel gradually becomes larger. Therefore, the diffuser section works 14b for decelerating the refrigerant flow so as to increase the refrigerant pressure, that is, converting the speed energy of the refrigerant into pressure energy.

Refrigerant coming from the diffuser section 14b the ejector pump 14 flows out, flows into a first evaporator 15 , The first evaporator 15 is disposed in, for example, an air duct of a vehicle air conditioning unit (not shown), and functions to cool the interior of a vehicle compartment.

A more detailed description follows. The air to be blown into the vehicle compartment becomes the first evaporator by the electric blower 15 sent and in the first evaporator 15 by evaporation of the nozzle section 14a the ejector pump 14 cooled in pressure reduced refrigerant. Ie. the low-pressure refrigerant from the ejector 14 absorbs heat from the air to be blown into the vehicle compartment and is in the first evaporator 15 evaporated. Therefore, the air to be blown into the vehicle compartment is cooled and it is possible to pass through the evaporator 15 obtained a cooling capacity. The first evaporator 15 vaporized vapor phase refrigerant is added to the compressor 12 sucked and again through the refrigerant circulation channel 11 circulated.

In the vapor compression refrigerant cycle device 10 with the ejector pump 14 This embodiment is a first branch channel 17 educated. The first branch channel 17 branches at an area in the refrigerant circulation channel 11 between the radiator 13 and the nozzle portion 14a the ejector pump 14 from. Then the first branch channel 17 with the refrigerant circulation channel 11 at the refrigerant suction port 14c the ejector pump 14 united. This branch channel 17 is also referred to as a channel for guiding the refrigerant into the refrigerant suction port 14c the ejector pump 14 designated. In the high-pressure channel of the refrigerant circuit branches the branch channel 17 from the downstream of the radiator 13 arranged pipe from where a relatively large amount of liquid refrigerant exists. In this embodiment, the downstream of the radiator forms 13 arranged branch section 16 a liquid refrigerant supply section. In this branch channel 17 is a throttle mechanism 18 arranged to reduce the pressure of the refrigerant with a predetermined throttle opening degree. The throttle mechanism 18 sees a throttle device in the branch channel 17 in front.

A second evaporator 19 is downstream of this throttling mechanism with respect to the refrigerant flow 18 arranged. This second evaporator 19 is disposed in, for example, a refrigerator (not shown) mounted in the vehicle and cools the air sent by an electric blower in the refrigerator.

A temperature sensor 22 is at a position near the second evaporator 19 arranged. The temperature of the air near the second evaporator 19 is with this temperature sensor 22 detected and a by this detection of the temperature sensor 22 received temperature signal is an electrical control unit (ECU) 21 entered.

A bypass channel 23 is between the refrigerant circulation channel 11 and the branch channel 17 intended. The bypass channel 23 is a channel to that from the compressor 12 output high-temperature refrigerant directly into the second evaporator 19 to flow. In particular, the bypass channel 23 is formed as a channel which communicates with the channel region between the compressor 12 and the radiator 13 and the channel area between the throttle mechanism 18 and the second evaporator 19 is connected, as in 1 and 2 shown.

An opening / closing device 24 (Switching device) is at a position in the bypass channel 23 arranged. The opening / closing device 24 switches the bypass channel 23 between a substantially refrigerant circulation state and a refrigerant blocking state, and is also referred to as a switching device. The opening / closing device 24 may include a valve mechanism in which the opening / closing by the electrical control unit 21 is controlled. It is normally controlled in a closed state and the circulation of the refrigerant in the bypass channel 23 will be blocked. The opening / closing device 24 is constructed so that when it is open, the high pressure high temperature refrigerant from the compressor 12 reduced in pressure and the refrigerant passes with a predetermined throttle opening.

A second branch channel 25 is designed to be from the bypass channel 23 at a position downstream of the opening / closing device 24 branches off and with an inlet side of the first evaporator 15 connected is. The second branch channel 25 is a channel through which the bypass channel 23 directly with the first evaporator 15 can be connected. In this branch channel 25 is a check valve 26a (Flow control unit, backflow prevention device) is provided. The check valve 26a allows the flow of refrigerant from the side of the opening / closing device 24 to the side of the first evaporator 15 , At the same time, it prevents the return flow of the refrigerant from the side of the first evaporator 15 to the side of the opening / closing device 24 (the second evaporator 19 ). In this embodiment, the bypass channel 23 downstream of the opening / closing device 24 branched second branch channel 25 with the refrigerant circulation channel 11 at a position between the refrigerant outlet of the ejector 14 and the refrigerant inlet of the first evaporator 15 united.

Downstream of the radiator 13 and upstream of the branching section 16 of the branch channel 17 is an opening / closing device 31 arranged in which the opening / closing by the electric control unit 21 is controlled. The opening / closing device 31 is also used as opening / closing means for opening and closing the refrigerant flow from the radiator 13 designated. When the opening / closing device 31 is closed, blocks the opening / closing device 31 essentially the refrigerant flow in the main path of the radiator 13 in the refrigerant circuit.

The following is a description of the operation of the vapor compression refrigerant cycle device 10 based on the above construction.

1. Cooling mode (Fig. 1)

1 shows the refrigerant flow (arrows of solid lines) in cooling mode. In cooling mode, the electric control unit 21 the opening / closing device 24 closed and the opening / closing device 31 open. When the compressor 12 is driven by the vehicle engine, flows through the compressor 12 compressed and brought into the state of high temperature and high pressure refrigerant into the radiator 13 , The high temperature high pressure refrigerant gets in the cooler 13 cooled by the outside air and condensed therein. After flowing out of the cooler 13 the liquid high-pressure refrigerant flows through the opening / closing device 31 and then into a refrigerant stream coming from the branching section 16 to the refrigerant circulation channel 11 goes, and a refrigerant flow from the branching section 16 through the branch channel 17 go, shared. The refrigerant flowing through the branch duct 17 flows, is at the throttle mechanism 18 reduced in pressure and brought into a state of low pressure. This low-pressure refrigerant in the second evaporator absorbs heat from the air sent through the electric fan in the refrigerator and is evaporated. This is how the second evaporator works 19 for cooling the interior of the cooling apparatus.

The refrigerant flowing through the refrigerant circulation duct 11 flows, flows into the nozzle section 14a the ejector pump 14 and will be at the nozzle section 14a reduced in pressure and stretched. Therefore, the pressure energy of the refrigerant at the nozzle portion becomes 14a converted into speed energy. The refrigerant is expelled from the jet opening, causing a pressure is reduced by the jet opening. This will be the second evaporator 19 vaporized vapor phase refrigerant through the refrigerant suction port 14c sucked by reducing the pressure in the vicinity of the jet opening.

That from the nozzle section 14a discharged refrigerant and that of the refrigerant suction port 14c sucked in refrigerant will be downstream of the nozzle section 14a mixed and flow into the diffuser section 14b , At the diffuser section 14b The speed energy (expansion energy) of the refrigerant is converted to pressure energy due to the increase in the channel area. This increases the pressure of the refrigerant in the diffuser section 14b , That from the diffuser section 14b the ejector pump 14 escaping refrigerant flows into the first evaporator 15 ,

At the first evaporator 15 The refrigerant absorbs heat from the air to be blown into the vehicle compartment by the electric blower and is vaporized. This is how the first evaporator works 15 for cooling the interior of the vehicle compartment. The vaporized vapor phase refrigerant enters the compressor 12 sucked and compressed therein and circulates again through the refrigerant circulation channel 11 , Here, an electromagnetic pressure control unit can control the displacement of the compressor so as to suppress the refrigerant discharge capacity of the compressor 12 to control.

Therefore you can through the first evaporator 15 the cooling capacity for cooling a space to be cooled, for example, the cooling capacity for cooling the interior of the vehicle compartment obtained. The flow rate of the refrigerant to the first evaporator 15 is set and further the speed (blow amount) of the electric blower is controlled, so that the cooling capacity can be controlled.

The refrigerant evaporation pressure of the first evaporator 15 is a pressure that is caused by the pressure increase of the refrigerant at the diffuser section 14b the ejector pump 14 receives. The outlet of the second evaporator 19 is with the refrigerant suction port 14c the ejector pump 14 connected. Therefore, it is possible to have the lowest pressure immediately after the pressure reduction at the nozzle section 14a receives, on the second evaporator 19 apply.

Therefore, the refrigerant evaporation pressure (the refrigerant evaporation temperature) of the second evaporator can be determined 19 lower than the refrigerant evaporation pressure (the refrigerant evaporation temperature) of the first evaporator 15 do. As a result, the first evaporator 15 be made to achieve a cooling effect in a relatively high temperature range, which is suitable for cooling the interior of the vehicle compartment. At the same time, the second evaporator 19 be made to achieve a cooling effect in an even lower temperature range, which is suitable for cooling the interior of the cooling apparatus.

In cooling mode, the pressure is at the first evaporator 15 by the pressure increasing effect of the ejector 14 higher than that at the second evaporator 19 made. In this vapor compression refrigerant cycle device 10 can the refrigerant flow from the first evaporator 15 to the second evaporator 19 through the in the branch channel 25 built-in check valve 26a be locked. Therefore, the cooling mode in the refrigerant cycle device 10 be carried out, whereby a cooling operation using the first evaporator 15 and the second evaporator 19 is carried out.

2. defrosting mode (Fig. 2)

2 shows the refrigerant flow (dashed line arrows) in defrosting mode. In the above cooling mode, the evaporators can 15 . 19 be operated under the condition that the refrigerant evaporation temperature is lower than 0 ° C. Therefore, a deterioration of the cooling performance due to frost formation on each evaporator 15 . 19 causes.

In this embodiment, each evaporator 15 . 19 by the control operation of the electric control unit 21 automatically defrosted. For example, the electric control unit determines 21 the presence or absence of frost in the second evaporator 19 based on the temperature sensor 22 that is near the second evaporator 19 is provided, detected temperature. Then the electrical control unit leads 21 the defrost mode for the evaporators 15 . 19 through when the electrical control unit 21 the formation of frost in the second evaporator 19 certainly.

When the temperature of the air immediately after flowing through the second evaporator 19 passing through the temperature sensor 22 is detected, to a value lower than a preset frost determination temperature Ta decreases, determines the electric control unit 21 that the second evaporator 19 Frost has, and the opening / closing device 24 is opened and the opening / closing device 31 will be closed.

Then it flows from the compressor 12 output high-temperature refrigerant at the radiator 13 past the bypass channel 23 , At the same time the Refrigerant flow from the downstream side of the radiator 13 to the nozzle section 14a the ejector pump 14 and the throttle mechanism 18 blocked.

The high-temperature refrigerant entering the bypass channel 23 has flowed through the opening / closing device 24 reduced with a throttle function in the pressure. Further, the pressure-reduced refrigerant flows from the opening / closing device 24 through the bypass channel 23 in the second evaporator 19 and flows through the branch channel 25 in the first evaporator 15 , At the same time, every evaporator works 15 . 19 as a refrigerant radiator, which radiates heat from the high-temperature refrigerant, thus removing frost. That from the second evaporator 19 escaping refrigerant flows through the refrigerant suction port 14c the ejector pump 14 and hits the high-temperature refrigerant from the branch channel 25 and flows into the first evaporator 15 ,

In a comparative example, in which a hot gas refrigerant circuit without the above branch passage 25 and the check valve 26 is constructed as in 3 and 4 illustrates that flows from the compressor 12 output high-temperature refrigerant by the following route: from the inlet of the second evaporator "a" to the outlet of the second evaporator "b", to the ejector 14 to the inlet of the first evaporator "c" and to the outlet of the first evaporator "d". therefore, in the hot gas refrigerant cycle of the comparative example, the refrigerant flow is relative to the first and second evaporators 15 . 19 serial. Therefore, in the comparative example, because the ejector 14 the refrigerant flow is resisted, the refrigerant pressure P1a at the inlet of the second evaporator "a" increases accordingly. Therefore, the temperature T1 at the inlet of the second evaporator becomes relatively higher relative to the temperature T2 at the inlet of the first evaporator, and the temperature difference tends to increase.

In contrast, this embodiment uses the one related to 1 and 2 described circle structure. That from the compressor 12 high-temperature refrigerant discharged in the defrosting mode can thereby be divided and into the second evaporator 19 and the first evaporator 15 be directed. A more detailed description follows. In the other construction (comparative example), the total flow amount G of the refrigerant flows out of the compressor 12 successively to the first and second evaporators 15 . 19 , In this embodiment, the flow rate G2 of the refrigerant is from the second evaporator 19 to the ejector pump 14 equivalent to a flow amount obtained by subtracting the flow rate G1 of the branch channel 25 flowing refrigerant from the flow rate G of the refrigerant from the compressor receives (G2 = G - G1). Thus, the flow rate of the second evaporator 19 and the ejector pump 14 reaching refrigerant relative to the total flow rate G of the compressor 12 discharged refrigerant in the defrosting mode can be reduced. That's why in the ejector pump 14 caused flow resistance to be reduced and the refrigerant pressure at the second evaporator 19 can be reduced from P1a in the comparative example to P1e as in 4 shown. In this embodiment, the inlet of the evaporator is plotted at the position marked "e" (refrigerant temperature line T3), and the plotted position of the outlet of the second evaporator is shifted to that marked "f".

The refrigerant flow with the flow rate G1, that of the bypass channel 23 to the branch channel 25 and to the inlet of the first evaporator 15 is conducted with the refrigerant flow with the flow amount G2 flowing from the outlet of the second evaporator "f" and through the ejector 14 passes, mixed. Then, it is brought into the state of enthalpy at the inlet of the first evaporator "g ^" where the enthalpy is higher than at the inlet of the first evaporator "c" in the comparative example. For this reason, the inlet temperature of the first evaporator 15 This embodiment is higher than the temperature of the first evaporator T2 in the comparative example and becomes close to the inlet temperature T2 of the second evaporator. Therefore, in the first embodiment, the temperature difference between the first and second evaporators 15 . 19 be reduced in total compared to the comparative example. As a result, deterioration of the cooling capacity after the defrosting mode and deterioration of the cooling speed can be suppressed. The for cooling (ie cooling in 5 ) time required after a start of the cooling mode can be achieved by reducing the temperature difference between the first and second evaporators 15 . 19 be reduced. In the first embodiment can be compared to the comparative example without the branch channel 25 achieve a time reduction of about four minutes, as in 5 shown.

In this embodiment, the opening / closing device 31 downstream of the radiator 13 provided so that the opening / closing device 31 closed in defrost mode. Therefore, the flow rate of the high temperature refrigerant flowing from the compressor 12 directly into the second evaporator 19 and the first evaporator 15 is increased. As a result The defrosting mode can be effectively carried out.

Second Embodiment

6 and 7 show a second embodiment of the invention. The second embodiment is by replacing the check valve 26a in the first embodiment by an on / off switching valve 26b (Flow control unit, backflow prevention device) realized.

The on / off switching valve 26b is one in the branch channel 25 built-in valve, its opening / closing by the electrical control unit 21 is controlled. For example, the on / off switching valve 26b designed so that it closes when the opening / closing device 24 in the bypass channel 23 is closed in cooling mode; and it is opened when the opening / closing device 24 in defrost mode.

In the second embodiment, the other parts of the refrigerant cycle device 10 be made similar to those of the first embodiment described above.

Therefore, in cooling mode, the in 6 represented refrigerant flow (arrows of solid lines) are formed; and in the defrosting mode, the in 7 represented refrigerant flow (arrows dashed lines) are formed, similar to the first embodiment described above. Accordingly, the same operation as in the first embodiment and its action and effect can be achieved.

(Third Embodiment)

8th to 10 illustrate a third embodiment of the invention. In the third embodiment, instead of the check valve 26a of the first embodiment, a flow adjusting valve 26c (Flow control unit, backflow prevention device) used; a temperature detector 27 for directly or indirectly detecting the refrigerant temperature on the refrigerant inlet side of the first evaporator 15 is provided; and a temperature detector 28 for directly or indirectly detecting the refrigerant temperature on the outlet side of the second evaporator 19 is planned. The flow adjustment valve 26c is arranged so that there is a flow rate through the branch channel 25 adjusting refrigerant. An opening degree of the flow adjusting valve 26c is set to zero in cooling mode. The temperature detector 27 is arranged to be in the first evaporator 15 to detect flowing refrigerant temperature. The temperature detector 28 is arranged to the from the second evaporator 19 to detect outflowing refrigerant temperature.

The valve opening of the flow adjustment valve 26c is through the electrical control unit 21 controlled. The flow adjustment valve 26c has a valve closing function, with which it is the branch channel 25 completely closes. The flow adjustment valve 26c has a flow control function that adjusts its valve opening degree when it is open and it controls the flow rate through the branch duct 25 adjusting refrigerant.

The temperature detectors 27 . 28 are temperature sensors, which are the inlet-side refrigerant temperature of the first evaporator 15 or the outlet side refrigerant temperature of the second evaporator 19 record directly. As a result of detection by the temperature detectors 27 . 28 obtained temperature signals are the electrical control unit 21 entered.

In the third embodiment, the electric control unit closes in the cooling mode 21 the opening / closing device 24 , brings the flow adjustment valve 26c in the closed state and opens the opening / closing device 31 , So will the in 8th illustrated refrigerant flow (arrows of solid lines) formed.

In defrosting mode the electric control unit opens 21 the opening / closing device 24 , brings the flow adjustment valve 26c in an open state and closes the opening / closing device 31 , So will the in 9 illustrated refrigerant flow (arrows dashed lines) formed.

The electric control unit 21 represents the valve opening degree of the flow adjusting valve 26c according to those of the temperature detectors 27 . 28 received temperature signals. A more detailed description follows. In the diagram of 10 becomes the inlet-side refrigerant temperature of the first evaporator 15 referred to as T4 and the outlet-side refrigerant temperature of the second evaporator 19 is called T5. The electric control unit 21 compares these refrigerant temperatures T4, T5 and works as follows. The lower the refrigerant temperature T4 is with respect to the refrigerant temperature T5, that is, the more the value of (T5-T4) increases, the further the electric control unit 21 the valve opening degree of the flow adjusting valve 26c to the completely open position; on the other hand, the electric control unit 21 the valve opening degree of the flow adjusting valve 26c the closer to the fully closed position, the higher the refrigerant temperature T4 is relative to the refrigerant temperature T5, ie, the greater the absolute value of (T5-T4) increases.

Therefore, in the defrosting mode, more high-temperature refrigerant can enter the evaporator (either 15 or 19 ), in which the refrigerant temperature is the lower of the first evaporator 15 and the second evaporator 19 is. Therefore, the defrosting mode can be effectively performed, and further, a defrosting time can be shortened.

In this example of 9 and 10 become the temperature detectors 27 . 28 for directly detecting the respective refrigerant temperatures, that is, the temperature sensors as intake side temperature detecting means for detecting the refrigerant temperature on the refrigerant inlet side of the first evaporator 15 and outlet side temperature detecting means for detecting the refrigerant temperature on the refrigerant outlet side of the second evaporator 19 used. Instead, the pressure of the refrigerant may also be measured using pressure sensors on the refrigerant inlet side of the first evaporator 15 and on the refrigerant outlet side of the second evaporator 19 and a refrigerant temperature corresponding to the pressure can be calculated and determined based on a preset map with the relationship between the refrigerant pressure and the refrigerant temperature. Furthermore, a temperature sensor for one of the temperature detectors can also be used 27 . 28 can be used and one pressure sensor can be used for the other.

(Fourth Embodiment)

11 and 12 show a fourth embodiment of the invention. The fourth embodiment is by adding a branch channel (ie, third branch channel) 29 and a check valve 30a (Flow control unit, backflow prevention device) to the refrigerant cycle device 10 of the first embodiment. The check valve 30a is arranged so that there is only one refrigerant flow from the refrigerant outlet side of the second evaporator 19 to the refrigerant inlet side of the first evaporator 15 allowed.

The branch channel 29 branches from a refrigerant downstream side of the second evaporator 19 that is, from a branching section between the second evaporator 19 and the refrigerant suction port 14c the ejector pump 14 , At the same time is the branch channel 29 with a refrigerant upstream side of the first evaporator 15 at a connecting portion between the refrigerant outlet of the ejector 14 and the refrigerant inlet of the first evaporator 15 connected. The check valve 30a is in this branch channel 29 and allows the flow of refrigerant from the side of the second evaporator 19 to the side of the first evaporator 15 , At the same time prevents the check valve 30a the return flow of the refrigerant from the side of the first evaporator 15 to the side of the second evaporator 19 ,

In the cooling mode, in the refrigerant cycle device of the fourth embodiment, the opening / closing device 24 closed and the opening / closing device 31 through the electrical control unit 21 open. So will the in 11 illustrated refrigerant flow (arrows of solid lines) formed. In the cooling mode, the refrigerant pressure is on the side of the first evaporator 15 higher than the refrigerant pressure on the side of the second evaporator 19 , Therefore, this gets out of the second evaporator 19 escaping refrigerant not through the branch channel 29 and flows through the refrigerant suction port 14c through the ejector pump 14 ,

In the defrosting mode of the refrigerant cycle device 10 of the fourth embodiment is by the electric control unit 21 the opening / closing device 24 opened and the opening / closing device 31 closed. So will the in 12 illustrated refrigerant flow (arrows dashed lines) formed. In the defrosting mode, the level of the refrigerant pressure is on the side of the second evaporator 19 slightly higher than that on the side of the first evaporator 15 , As a result, this flows out of the second evaporator 19 escaping refrigerant at the ejector 14 over and passes through the branch channel 29 and the check valve 30a and flows into the first evaporator 15 ,

This makes it possible to prevent the high-temperature refrigerant coming out of the bypass channel 23 in the second evaporator 19 flows from the ejector 14 experiences a resistance. Therefore, the refrigerant pressure at the second evaporator 19 can be further reduced and the refrigerant temperature can between the first and the second evaporator 15 . 19 be made more uniform in the defrosting mode.

An on / off switching valve (second on / off switching valve) may be used in the fourth embodiment instead of the check valve 30a be used. In this case, opening / closing will be in the branch channel 29 provided on / off switching valve by the electrical control unit 21 controlled. For example, this will be in the branch channel 29 provided on / off switching valve open when the opening / closing device 24 is opened and closed when the opening / closing device 24 is closed. Also in this case, the same effect as mentioned above can be obtained.

Alternatively, in the fourth embodiment, instead of the check valve 30a a flow adjustment valve can be used. In this case, the flow adjusting valve can be closed and makes it possible to control the flow rate of the refrigerant by adjusting the valve opening.

In addition, the check valve 26a as in the second or third embodiment by the on / off switching valve 26b or the flow adjustment valve 26c be replaced.

(Fifth Embodiment)

13 and 14 show a fifth embodiment of the invention. In the fifth embodiment, the vapor compression refrigerating cycle apparatus includes 10 a gas / liquid separator 35 flowing in a refrigerant stream downstream of the first evaporator 15 is provided; and a branch channel 36 acting as a refrigerant channel between the gas / liquid separator 35 and the refrigerant suction port 14c the ejector pump 14 is provided.

The gas / liquid separator 35 is, for example, a container body. The gas / liquid separator 35 separate this from the first evaporator 15 flowing refrigerant in vapor and liquid and directs the vapor-phase refrigerant to the refrigerant suction side of the compressor 12 and collects the liquid phase refrigerant therein.

The branch channel 36 is provided from a liquid-phase refrigerant outlet side of the gas-liquid separator 35 with the refrigerant suction port 14c the ejector pump 14 connected is. In this embodiment, the liquid storage portion of the gas-liquid separator becomes 35 as a liquid refrigerant supply section for supplying liquid refrigerant into the branch passage 36 used. The throttle mechanism 18 and the second evaporator 19 are in this order from the gas / liquid separator side 35 of the branch channel 36 arranged out. Next is an opening / closing device 32 on the inlet side of the throttle mechanism 18 ie between the gas / liquid separator 35 and the throttle mechanism 18 intended. The opening / closing device 32 opens and closes the branch channel 36 under the control of the electric control unit 21 , The opening / closing device 32 can also be downstream of the throttle mechanism 18 (between the throttle mechanism 18 and the second evaporator 19 ) be provided. Alternatively, the opening / closing device 32 with the throttle mechanism 18 combined to form an integrated construction.

In the vapor compression refrigerant cycle device 10 of the fifth embodiment, during the cooling mode by the electric control unit 21 the opening / closing device 24 closed and become the opening / closing devices 31 . 32 open. So will the in 13 illustrated refrigerant flow (arrows of solid lines) formed. A more detailed description follows. The in the refrigerant circulation channel 11 flowing refrigerant passes from the radiator 13 through the nozzle section 14a the ejector pump 14 , flows out of the first evaporator 15 and is at the gas / liquid separator 35 separated into vapor and liquid. Then, the vapor-phase refrigerant is removed from the gas-liquid separator 35 in the compressor 12 sucked. The liquid-phase refrigerant in the gas-liquid separator 35 flows into the branch channel 36 and passes through the throttle mechanism 18 and the second evaporator 19 , Then that is through the second evaporator 19 reaching refrigerant into the refrigerant suction port 14c the ejector pump 14 sucked. Therefore, causes the first evaporator 15 performs a cooling operation in a relatively high temperature region, which is suitable for cooling the interior of the vehicle compartment, as in the first embodiment. At the same time it causes the second evaporator 19 performs a cooling operation in an even lower temperature range, which is suitable for cooling the interior of the cooling apparatus, as in the first embodiment.

In the defrosting mode of the refrigerant cycle device 10 be through the electrical control unit 21 the opening / closing device 24 opened and the opening / closing devices 31 . 32 closed. So will the in 14 illustrated refrigerant flow (arrows dashed lines) formed. Ie. that from the compressor 12 discharged high-temperature refrigerant flows into the bypass passage 23 , At the same time, the refrigerant flow from the downstream side of the radiator 13 to the nozzle section 14a the ejector pump 14 blocked.

After flowing from the compressor 12 in the bypass channel 23 The high temperature refrigerant is passed through the opening / closing device 24 reduced in pressure with a predetermined degree of throttling. The decompressed refrigerant from the opening / closing device 24 continues to flow from the bypass channel 23 in the second evaporator 19 and at the same time flows from the branch channel 25 in the first evaporator 15 , That from the ejector pump 14 outflowing refrigerant is with the from the branch channel 25 flowing high-temperature refrigerant mixed and the mixed refrigerant flows into the first evaporator 15 ,

Thus, in the refrigerant cycle device 10 of the fifth embodiment, the same refrigerant flow as in the first embodiment are formed. Therefore, the difference in the refrigerant temperature between the evaporators 15 . 19 be reduced in the defrosting mode. As a result, deterioration of the cooling performance after the defrosting mode and deterioration of the cooling speed after restarting the cooling mode can be suppressed.

(Modifications of the embodiments)

In the first to fifth embodiments described above, the opening / closing device 31 on the refrigerant outlet side of the radiator 13 intended. Instead, the opening / closing device 31 also on the refrigerant inlet side of the radiator 13 be provided. Next, the cooler 13 be designed so that its heat radiation power is adjusted by the amount of air of the cooling fan, and the opening / closing device 31 can be omitted. In this case, in the defrosting mode, the amount of air blown through the cooling fan is set to zero, so that the heat radiating performance of the radiator 13 is set to about zero.

Furthermore, the branch point of the bypass channel 23 also downstream of the radiator 13 be provided.

In the first to fourth embodiments described above, downstream of the first evaporator 15 a gas / liquid separator may be provided. In this case, the compressor can 12 clean only the vapor phase refrigerant sucking and the occurrence of liquid compression in the compressor 12 can be prevented.

In addition, in the first to fifth embodiments described above, a temperature sensor may be close to the first evaporator 15 can be provided and a control unit can be provided which the opening / closing device 24 controls to execute a frost prevention control based on the temperature detected by this temperature sensor. In this case, the control unit determines the state of frost formation in the first evaporator 15 and the amount of frost formed based on the temperature detected by the temperature sensor. When the control unit determines that the first evaporator is in the frost formation state, ie, freezes, it opens the opening / closing device 24 and closes the opening / closing device 31 to perform the defrosting mode. Alternatively, the individual evaporators 15 . 19 may be provided with a temperature sensor as means for detecting a frost formation, and a defrosting control may be carried out independently on an evaporator base. Further, instead of the frost formation detection by a temperature sensor, the defrosting mode may also be performed so that the opening / closing device 24 opened at predetermined equal time intervals and the opening / closing device 31 is closed.

(Sixth Embodiment)

Hereinafter, a description will be made of a refrigerant cycle device in a sixth embodiment with reference to FIG 15 to 18B given.

In the sixth embodiment, the branch channel 25 and the check valve 26a which have been described in the above first embodiment, not provided in comparison with the first embodiment. Therefore, during the defrosting mode, all of the compressor flows 12 discharged refrigerant through the bypass channel 23 in the second evaporator 19 and flows through the ejector 14 in the first evaporator 15 ,

In the sixth embodiment, the first evaporator 15 arranged in, for example, a vehicle compartment to the by a first blower 20a to cool air to be blown into the vehicle compartment, and the second evaporator 19 is disposed in, for example, a refrigerator (not shown) in a vehicle and functions to cool the interior of the refrigerator. This embodiment is designed so that the air in the refrigerator through a second blower 20B to the second evaporator 19 is sent.

Further, in the sixth embodiment, a variable displacement compressor 12 used and an output capacity of the variable displacement compressor 12 discharged refrigerant is by an electromagnetic pressure control section 12a in accordance with a control signal from the electric control unit 21 controlled.

The bypass channel 23 holding the refrigerant channel on the discharge side of the compressor 12 and the inlet portion of the second evaporator 19 directly connects, is provided. A locking mechanism 24 (Opening / closing device) is in this bypass channel 23 intended. In particular, the locking mechanism 24 be constructed of a normally closed electromagnetic valve, which is opened only when it is energized, for example.

This bypass channel 23 is a hot gas duct through which the compressor 12 discharged hot gas refrigerant directly into the second evaporator 19 can be initiated. If the surface of the second evaporator 19 freezes, becomes the locking mechanism 24 opened to have a predetermined restriction, so that from the compressor 12 discharged hot gas refrigerant at the radiator 13 and the throttle mechanism 18 passing directly to the second evaporator 19 flows.

Normally (cooling mode) when the second evaporator 19 does not need to be defrosted, becomes the locking mechanism 24 in accordance with a control signal from the electric control unit described later 21 kept in a locked state. For this reason, in the cooling mode, the refrigerant does not pass through the bypass passage 23 passed; therefore, a refrigerant circuit is generated by the operation of the compressor 12 executed. Therefore, the cooling operation for cooling the interior of the vehicle compartment by the first evaporator 15 can be performed and at the same time, the cooling operation of the cooling of the interior of the cooling apparatus by the second evaporator 19 be performed.

The temperature sensor 22 is at a position close to the second evaporator 19 arranged. The temperature of the air immediately after flowing through the second evaporator 19 is through this temperature sensor 22 detected. Measuring signals of the temperature sensor 22 become the electric control unit described later 21 entered.

In the defrosting mode, at least the second evaporator 19 based on the temperature of the air in proximity to the second evaporator 19 defrosted by the temperature sensor 22 is detected. In defrost mode, the locking mechanism 24 in accordance with a control signal from the electric control unit 21 open. For this reason, the high-temperature high-pressure vapor-phase refrigerant reaches the discharge side of the compressor 12 through the bypass channel 23 and flows into the second evaporator 19 , So that can be on the surface of the second evaporator 19 formed frost melted and removed.

This embodiment is constructed such that the following elements correspond to control signals from the electric control unit 21 electrically controlled: the electromagnetic pressure control section 12a the compressor with variable displacement 12 , the first and the second blower 20A . 20B , the throttle mechanism 18 and the same.

The first evaporator 15 is an evaporator, the heat between the at the nozzle section 14a the ejector pump 14 in the pressure reduced refrigerant and by the first blower 20A exchanges skillful air in the vehicle compartment; and thereby allows the refrigerant to absorb heat from the air in the vehicle compartment.

16A shows the first evaporator 15 , As in 16A is the first evaporator 15 in this embodiment, a heat exchanger of the fin and tube type with one of tubes 110 and ribs 120 constructed core section 110 . 120 ,

The first evaporator 15 is composed of several elements, such as the core section 110 . 120 and a left and a right collection container 130 , Each item containing these components of the evaporator 15 is formed of aluminum or an aluminum alloy. The evaporator 15 is constructed by assembling these members by press fitting, caulking, fastening by means of jig or the like, and joining the assembled member with the solder filling material provided in advance on the surface of each member by integral soldering.

In the core section 110 . 120 is a predetermined total number of multiple tubes 110 in which the refrigerant flows, and several ribs 120 , which are formed in a plate shape arranged. Ribs 120 are in the longitudinal direction of the tubes 110 arranged with a predetermined rib spacing corresponding to the cooling load in the vehicle compartment.

Each of the several pipes 110 is a tube having an inner diameter of φd in a substantially cylindrical shape, for example. The pipes 110 are arranged along the air flow direction in two rows on the upstream side and on the downstream side in a zigzag pattern. A predetermined number N1 of the tubes 110 is arranged at a predetermined distance.

The paired collection containers 130 , in the layering direction of the tubes 110 are at the longitudinal ends of the several tubes 110 intended. Each of the collection containers 130 is integrally formed from a container portion, a core plate and a face plate, which are not shown in the drawing.

The container portion (not shown) is a box-like case body having a substantially U-shaped section and an opening on the core plate side. The core plate (not shown) has a die forging section, not shown, at both its ends in the direction of its short sides and is formed in a substantially U-shape. The core plate has a plurality of tube insertion holes (not shown) at positions corresponding to the ends of the tubes 110 are formed.

The ends of the pipes 110 are connected to these tube insertion holes and the container spaces and the inside of the tubes 110 are thereby associated with each other. The front plate of the collection container 130 is an element for closing both ends of the container space formed by the container portions and the core plates.

At one end of the right collector 130 is a refrigerant inlet 140 formed, through which the refrigerant in the sump 130 flows. At one end of the left collector 130 is a refrigerant outlet 150 formed by the refrigerant, which has been subjected to a heat exchange, from the collecting container 130 flows.

16B shows the second evaporator 19 , The second evaporator 19 exchanges heat between the throttle mechanism 18 in the pressure reduced refrigerant and by the second blower 20B skillful air in the refrigerator out. The second evaporator 19 allows the refrigerant to absorb heat from the air in the refrigerator.

As in 16B Illustrated is the second evaporator 19 in this embodiment, a fin and tube type heat exchanger having a core portion made of tubes 110 and ribs 120 is constructed similar to those of the first evaporator 15 ,

However, the second evaporator uses 19 the following construction as the several pipes 110 between the paired collection containers 130 arranged: tubular tubes 110 with an inner diameter of Φd formed in a substantially cylindrical shape and in the channel cross-sectional area on the refrigerant side with those in the first evaporator 15 used are identical. In this example, the second evaporator is 19 designed so that the number N2 of the tubes 110 smaller than the number N1 of the tubes 110 in the first evaporator 15 is.

In other words, the second evaporator 19 is formed so that the flow resistance on the refrigerant side is greater than the flow resistance on the refrigerant side of the first evaporator 15 is. Ie. the first and the second evaporator 15 . 19 are constructed so that the pressure loss of the refrigerant in the second evaporator 19 greater than the pressure loss of the refrigerant in the first evaporator 15 is.

A predetermined total number of ribs 120 for the second evaporator 19 is disposed at a predetermined fin pitch corresponding to the cooling load in the refrigerator. Therefore, the total number of ribs is different 120 of the second evaporator 19 from that of the first evaporator 15 ,

In this embodiment, the first evaporator 15 and the second evaporator 19 designed so that the paired collection containers 130 at both ends of the tubes 110 are arranged. The construction of the first evaporator 15 and the second evaporator 19 is not limited to this. For example, the first evaporator 15 and the second evaporator 19 also be constructed so that the following is realized: the openings at both ends of the tubes 110 are using connecting tubes (not shown) in a substantially U-shape without using the collection container 130 connected. In this case, the refrigerant flowing into the refrigerant inlet flows 140 flows, left, right and then left to U. sweeping in the tubes 110 to repeat, and flows through the refrigerant outlet 150 out.

The following is a description of the operation of the refrigerant cycle device 10 this embodiment, which is constructed as mentioned above. First, the cooling mode of the refrigerant cycle device will now be described 10 described. When the compressor 12 is operated, the refrigerant is at the compressor 12 compressed and brought into a high temperature high pressure condition. That from the compressor 12 discharged refrigerant flows into the radiator 13 and is cooled by the outside air and can condense. After flowing out of the cooler 13 the high-pressure refrigerant enters a flow through the refrigerant circulation passage 11 and a current through the branch channel 17 divided.

In cooling mode, in which the second evaporator 19 does not need to be defrosted (normal time), the throttle mechanism works 18 in the branch channel 17 as a fixed throttle device according to a control signal from the electric control unit 21 , That's why it's going through the branch channel 17 flowing refrigerant at the throttle mechanism 18 reduced in pressure and brought into a low pressure state. This low-pressure refrigerant absorbs in the second evaporator 19 Heat out through the second blower 20B sent air in the refrigerator and is evaporated. So leads the second evaporator 19 the Process of cooling the interior of the refrigerator through.

This embodiment is constructed such that the throttle mechanism 18 is controlled as a fixed throttle device. The construction of the embodiment is not limited thereto. The throttle mechanism 18 can also be controlled as a variable throttle device, so that its opening is adjusted. It is therefore possible to control the flow rate of the refrigerant flowing through the first branch passage 17 passes and in the second evaporator 19 flows, to regulate. Therefore, the cooling capacity for cooling a space to be cooled (in particular, the space in the refrigerator) using the second evaporator 19 by controlling the rotational speed (amount of blown air) of the second blower 20B at the electrical control unit 21 to be controlled.

That from the second evaporator 19 outgoing vapor-phase refrigerant is in the refrigerant suction port 14c the ejector pump 14 sucked. Further, the refrigerant flow flows through the refrigerant circulation passage 11 in the nozzle section 14a the ejector pump 14 so that the refrigerant at the nozzle section 14a reduced in pressure and expanded. Therefore, the pressure energy of the refrigerant at the nozzle portion becomes 14a converted into velocity energy and the refrigerant is accelerated and expelled from the jet opening. In this case, the pressure drops in the vicinity of the jet opening and the second evaporator 19 vaporized vapor phase refrigerant is due to this pressure drop through the refrigerant suction port 14c sucked.

That of the nozzle section 14a discharged refrigerant and through the refrigerant suction port 14c sucked in refrigerant will be downstream of the nozzle section 14a mixed and flow into the diffuser section 14b , At the diffuser section 14b The speed energy (expansion energy) of the refrigerant is converted into pressure energy by increasing the channel area. This increases the pressure of the refrigerant. That from the diffuser section 14b the ejector pump 14 escaping refrigerant flows into the first evaporator 15 ,

At the first evaporator 15 The refrigerant absorbs heat from the ambient air to be discharged into the vehicle compartment and evaporates. The vaporized vapor phase refrigerant enters the compressor 12 sucked and compressed therein and circulates again through the refrigerant circulation channel 11 , The electric control unit 21 can the displacement of the compressor 12 control and thereby the refrigerant discharge capacity of the compressor 12 Taxes.

So can the cooling capacity of the first evaporator 15 for cooling a space to be cooled, in particular the cooling capacity of the first evaporator 15 for cooling the interior of the vehicle compartment, by the electric control unit 21 to be controlled. In this embodiment, the flow rate of the first evaporator 15 set the flow of refrigerant and further the speed (amount of blown air) of the first blower 20A controlled, so the cooling capacity of the first evaporator 15 to control.

The refrigerant evaporation pressure of the first evaporator 15 is a pressure that can be increased by increasing the pressure of the refrigerant on the diffuser section 14b receives. The refrigerant outlet of the second evaporator 19 is with the refrigerant suction port 14c the ejector pump 14 connected. Therefore, it is possible compared to the first evaporator 15 the low pressure on the second evaporator 19 exercise.

Therefore, the refrigerant evaporation pressure (the refrigerant evaporation temperature) of the second evaporator 19 lower than the refrigerant evaporation pressure (the refrigerant evaporation temperature) of the first evaporator 15 be made. As a result, the first evaporator 15 for causing a cooling effect in a relatively high temperature region suitable for cooling the interior of the vehicle compartment. At the same time, the second evaporator 19 be made to perform a cooling effect in a region of even lower temperature, which is suitable for cooling the interior of the cooling apparatus.

The second evaporator 19 can be operated under the condition that the refrigerant evaporation temperature is lower than 0 ° C. Therefore, a deterioration of the cooling capacity caused by frost (frost formation) on the second evaporator 19 is causing a problem. In this embodiment, the second evaporator 19 To cope with this, automatically defrosted by taking the following action: the temperature sensor 22 is close to the second evaporator 19 arranged and the presence or absence of frost in the second evaporator 19 is through the electrical control unit 21 based on by this temperature sensor 22 detected temperature determined.

A more detailed description follows. When passing through the temperature sensor 22 detected temperature of the air in the vicinity of the second evaporator 19 to a value lower than a preset frost determination temperature Ta sinks, determines the electric control unit 21 that the second evaporator 19 freezes, and opens the locking mechanism 24 (Opening / closing device).

As a result, the high-temperature high-pressure vapor-phase refrigerant reaches the discharge side of the compressor 12 through the bypass channel 23 and flows into the second evaporator 19 , Therefore, the on the surface of the second evaporator 19 formed frost are melted and removed and the defrosting process of the second evaporator 19 can be done by a very simple construction.

By performing this defrosting mode, the temperature of the air becomes close to the second evaporator 19 is increased to a defrosting end temperature Tb which is higher than the frost determination temperature Ta by a predetermined temperature α (Tb = Ta + α). Then the electric control unit determines 21 that the defrosting mode should be ended and brings the locking mechanism 24 again in the locked state. Therefore, the throttle mechanism works 18 again as a fixed throttle device and the second evaporator 19 is also returned to the normal state in which performs the cooling effect.

In this defrosting mode, the electric control unit performs 21 such a controller that the first blower 20A and the second fan 20B are brought into a stop state. As a result, when frost on the surface of the second evaporator 19 is formed and the temperature of the air in the vicinity thereof falls to the frost determination temperature Ta or below, the cooling effect of the first evaporator 15 stopped until the temperature of the air is close to the second evaporator 19 rises to the defrosting end temperature Tb or higher.

In order to shorten this defrosting time, this embodiment is constructed such that the flow resistance on the refrigerant side of the second evaporator 19 greater than the flow resistance on the refrigerant side of the first evaporator 15 is. A more detailed description follows. Considerations of the inventors of this application showed the following: When the flow resistance of the second evaporator 19 greater than the flow resistance of the first evaporator 15 is made, the temperature of the second evaporator rises 19 flowing refrigerant and this increases the average temperature of the through the pipes 110 of the second evaporator 19 flowing refrigerant.

The following is a description of the above relationships with reference to the Mollier diagram in FIG 17 indicating the behavior of the circle in the defrosting mode of this embodiment. In the drawing of 17 the solid line indicates the circular behavior in the sixth embodiment, which is constructed so that the second evaporator 19 in terms of the flow resistance on the refrigerant side larger than the first evaporator 15 is; and the dashed line indicates the circular behavior observed when the circuit is constructed so that the second evaporator 19 and the first evaporator 15 are equal to each other in terms of flow resistance.

Point A of 17 shows the state of the pressure of the discharged refrigerant, that on the compressor 12 compressed and an enthalpy. Further shows in 17 Point B the state of the second evaporator 19 flowing refrigerant on; Point C shows the state of the second evaporator 19 outflowing refrigerant on; Point D shows the state of the first evaporator 15 flowing refrigerant on; and point E shows the state of the first evaporator 15 outflowing refrigerant.

Point B ₀ , in the drawing of 17 is shown, shows the state of the second evaporator 19 flowing refrigerant when the second evaporator 19 and the first evaporator 15 are formed so that they are identical to each other with respect to the flow resistance. A pressure drop from point C to point D represents a pressure loss that occurs when from the second evaporator 19 escaping refrigerant into the ejector 14 flows. The pressure drop from point A to point B represents the pressure drop that occurs when coming from the compressor 12 discharged refrigerant through the bypass channel 23 and the locking mechanism 24 flows.

The pressure drop from point B to point C represents a pressure loss that occurs when the refrigerant passes through the second evaporator 19 flows. The pressure drop from point D to point E represents a pressure loss that occurs, warming the refrigerant through the first evaporator 15 flows.

The pressure drop from point B ₀ to point C represents a pressure loss that occurs when the refrigerant passes through the second evaporator 19 which is designed to be identical to the first evaporator in terms of flow resistance. It is indicated with substantially the same gradient as the oblique line connecting point D and point E.

Therefore, the oblique line connecting point B and point C is steeper than the oblique line connecting point B ₀ and point C. Ie. it has been found that when the gradient of the oblique line connecting point B and point C becomes larger, the refrigerant temperature at point B has increased larger than at point B ₀ in the Mollier diagram; in the Mollier diagram, the temperature at point B is exactly ₀ T1 and the temperature at point B is T2. Ie. the temperature T2 at point B is higher than the temperature T1 at point B ₀ with respect to the isotherms (IL (T2), IL (T1)).

Accordingly, the following advantage results when the second evaporator 19 and the first evaporator 15 are formed so that the former with respect to the flow resistance is greater than the latter, as in this embodiment: In the defrosting mode, the temperature of the in the second evaporator 19 flowing refrigerant higher and the average temperature of the through the pipes 110 of the second evaporator 19 flowing refrigerant can be compared to the following cases where the second evaporator 19 and the first evaporator 15 are formed so that they are identical with respect to the flow resistance, are increased.

Thus, in this embodiment, a defrosting time compared to cases in which the second evaporator 19 and the first evaporator 15 are formed so that they are identical with respect to the flow resistance, are shortened. If the second evaporator 19 and the first evaporator 15 be formed so that the former is lower than the latter in terms of flow resistance, the temperature of the second evaporator in the 19 flowing refrigerant are not increased because the gradient of the oblique line connecting point B and point C is more moderate than the gradient of the oblique line connecting point B ₀ and point C.

18A and 18B FIG. 15 are graphs showing the relationship between the defrosting-time ratio according to this embodiment and the defrosting-time ratio obtained when the second evaporator 19 and the first evaporator 15 are made to be identical in flow resistance (same flow resistance) when the outside air temperature (TAM) is taken as a parameter. 18A shows the Entfrastungszeitverhältnis obtained when the outdoor air temperature TAM 35 ° C, and 18B shows that obtained when the outside air temperature TAM is 0 ° C. The defrosting time ratio refers to a ratio of a defrosting time to a normal operation time.

When the outdoor air temperature TAM is 35 ° C, as in 18A As shown, the defrost time ratio can be compared with the defrosting time ratio obtained in cases where the second evaporator 19 and the first evaporator 15 are formed so that they are identical in terms of flow resistance to each other, be reduced in this embodiment by about 30%.

When the outside air temperature TAM is 0 ° C, as in 18B 1, the defrost time ratio can be compared with the defrosting time ratio obtained in the cases where the second evaporator 19 and the first evaporator 15 are formed so that they are identical in terms of flow resistance to each other, be reduced by about 60% in this embodiment. Ie. When the outside air temperature decreases, the defrosting time ratio in this embodiment can be significantly reduced.

In the ejector refrigerant cycle of the sixth embodiment, the first evaporator is 15 and the second evaporator 19 using the pipes 110 formed of identical channel cross-sectional area on the refrigerant side. They are also designed so that the number of tubes 110 in the second evaporator 19 smaller than the number of tubes 110 in the first evaporator 15 is. Thus, the refrigerant flow resistance of the second evaporator 19 greater than the refrigerant flow resistance of the first evaporator 15 be made.

In defrost mode, this flows from the compressor 12 output high-pressure refrigerant to the second evaporator 19 , to the ejector pump 14 and to the first evaporator 15 in this order. Here, the flow resistance is on the refrigerant side of the second evaporator 19 greater than the flow resistance on the refrigerant side of the first evaporator 15 , This increases the pressure loss at the second evaporator 19 and the inlet refrigerant temperature of the second evaporator 19 increases. This increase in the inlet refrigerant temperature of the second evaporator 19 increases the mean temperature of the second evaporator 19 flowing refrigerant and consequently the defrosting time can be shortened.

In this embodiment, in a normal refrigeration cycle operation, in which the lock mechanism flows 24 is closed, a branched off part of the refrigerant to the second evaporator 19 and the entire refrigerant flowing through the circuit flows to the first evaporator 15 , Further on, the second evaporator 15 positioned on the upstream side, a refrigerant having a relatively large amount of a liquid portion flows to the second evaporator 19 ,

For this reason, even if the second evaporator 19 has a relatively large flow resistance, the generation of excessive pressure loss in the second evaporator 19 prevented during normal operation. Because the first evaporator 15 has a relatively low flow resistance, even if the entire flow rate of the cooling circuit in normal operation by the first evaporator 15 flows, generating an excessive pressure loss in the first evaporator 15 prevented.

(Seventh Embodiment)

In the above sixth embodiment, the second evaporator 19 and the first evaporator 15 designed so that the former is greater in terms of flow resistance than the latter. Ie. in the seventh embodiment, the first evaporator 15 and the second evaporator 19 using the pipes 110 formed of identical channel cross-sectional area on the refrigerant side, wherein the number of tubes 110 of the second evaporator 19 smaller than the number of tubes 110 of the first evaporator 15 is done. The second evaporator 19 and the first evaporator 15 However, they may also be formed so that the former with respect to the channel cross-sectional area of the tubes 110 smaller than the latter is.

As in 19A and 19B shown, is each of the pipes 110 of the first evaporator 15 formed so that it has an inner diameter φd1, and each of the tubes 110 of the second evaporator 19 is formed to have an inner diameter φd2 smaller than φd1. The numbers N of the arranged pipes 110 are in the first evaporator 15 and second evaporator 19 identical to each other.

With this construction, it is possible to control the flow resistance on the refrigerant side of the second evaporator 19 greater than the flow resistance on the refrigerant side of the first evaporator 15 close. Therefore, the inlet temperature of the second evaporator becomes 19 higher if the pressure loss on the inlet side of the second evaporator 19 gets bigger. This increase in the inlet temperature increases the average temperature of the second evaporator 19 flowing refrigerant and so a defrosting time can be shortened.

In the refrigerant cycle device of the seventh embodiment, the other parts may be made similar to those of the above-described sixth embodiment, thereby obtaining the same advantages as those of the above-described sixth embodiment.

(Eighth Embodiment)

In this embodiment, as in FIG 20A and 20B shown, the pipes 110 of the first evaporator 15 designed so that they have a length L1, and the tubes 110 of the second evaporator 19 are formed to have a length L2 longer than L1. The numbers N of the arranged pipes 110 are in the first evaporator 15 and in the second evaporator 19 identical to each other. The first evaporator 15 and the second evaporator 19 use the pipes 110 with the identical refrigerant channel cross-sectional area.

With this construction, it is possible to control the flow resistance on the refrigerant side of the second evaporator 19 greater than the flow resistance on the refrigerant side of the first evaporator 15 close.

In the refrigerant cycle device 10 of the eighth embodiment, the other parts may be made similar to those of the above-described sixth embodiment, thereby obtaining the same advantages as those of the above-described sixth embodiment.

Ninth Embodiment

In a refrigerant cycle device 10 of a ninth embodiment is as in 21 shown, a cooling unit 37 from the first evaporator 15 and the second evaporator 19 built up. The cooling unit 37 cools a common space to be cooled (in particular, the space of a refrigerator in a vehicle) to a low temperature such as 0 ° C or lower.

A more detailed description follows. The first evaporator 15 is upstream of the first fan with respect to the airflow 20A arranged and the second evaporator 19 is with respect to the air flow downstream of the first evaporator 15 arranged. Cool air passing through the second evaporator 19 is reached, is blown into the room to be cooled (room in the refrigerator). The first evaporator 15 and the second evaporator 19 For example, they may be integrally formed by soldering.

In this embodiment, the common space to be cooled (space in Refrigerator) with the first evaporator 15 and the second evaporator 19 cooled to a low temperature of 0 ° C or lower. Therefore, it is necessary to perform a defrosting operation for both the first evaporator 15 as well as the second evaporator 19 perform.

The following is a description of the operation of the ejector refrigerant cycle device 10 with the cooling unit 37 , In a normal operation (cooling mode) are the compressor 12 , an unillustrated cooling fan for the radiator 13 and the fan 20A (first blower) of the cooling unit 37 in operation. The throttle mechanism 18 is controlled in a predetermined throttle state. The locking mechanism 24 is kept in a locked state.

Thus, in the refrigerant cycle device 10 of the ninth embodiment by the blower 20A sent air by a heat absorbing effect due to the evaporation of the refrigerant at the first evaporator 15 and at the second evaporator 19 cooled. The room to be cooled in the cooling unit 37 can be cooled by it. Ie. a normal cooling process can be performed using the first and second evaporators 15 . 19 in the refrigerant cycle device 10 be performed.

When passing through the temperature sensor 22 detected temperature falls below the frost determination temperature determines the electrical control unit 21 in that the first and second evaporators 15 . 19 freeze, and changes the operation mode in the refrigerant cycle device 10 to the defrosting mode.

A more detailed description follows. When the defrosting mode is set, the electric control unit opens 21 the locking mechanism 24 and brings the blower at the same time 20A in a stop state. The cooling fan for the radiator 13 may be in a defrost mode or in an operating state in defrost mode.

As a result of the opening of the locking mechanism 24 this flows from the compressor 12 output high-temperature refrigerant (hot gas) directly into the second evaporator 19 , so on the second evaporator 19 Heat is radiated and the temperature of the refrigerant is lowered by a predetermined amount; and the medium-temperature refrigerant thus obtained passes through the refrigerant suction port 14c the ejector pump 14 and flows into the first evaporator 15 , As mentioned above, this flows from the compressor 12 output high-temperature refrigerant to both the second evaporator 19 as well as the first evaporator 15 in this order and the second evaporator 19 and the first evaporator 15 are thereby defrosted at the same time.

In this embodiment, the second evaporator 19 and the first evaporator 15 is formed so that the flow resistance on the refrigerant side of the second evaporator 19 greater than the flow resistance on the refrigerant side of the first evaporator 15 is. As a result, the pressure loss on the inlet side of the second evaporator 19 increases and thus increases the inlet temperature of the second evaporator 19 , This increase in the inlet temperature increases the average temperature of the second evaporator 19 flowing refrigerant. Further, the medium-temperature refrigerant obtained by radiating heat and lowering its temperature by a predetermined amount on the second evaporator 19 gets into the first evaporator 15 be directed.

Therefore, it is possible to use the first and second evaporators 15 . 19 to defrost and the defrost time for the second evaporator 19 and the first evaporator 15 to shorten further.

(Further embodiments)

Although the present invention has been fully described in connection with the preferred embodiments and modifications thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art.

For example, in the refrigerant cycle device 10 Each of the above-described first to fifth embodiments, the constructions of the first evaporator 15 and the second evaporator 19 Any of the above-described sixth to eighth embodiments may be used.

In the sixth to ninth embodiments, the first and second evaporators are 15 . 19 from heat exchangers of the rib and tube type with the core section 110 . 120 from pipes 110 and ribs 120 constructed. The sixth to ninth Embodiments are not limited to this construction. Instead, the evaporators can 15 . 19 be designed from heat exchangers such that the tubes 110 layered flat tubes are and corrugated ribs 120 between the flat tubes 110 are arranged.

In the sixth to ninth embodiments, the inside of the tubes 110 formed from a smooth channel. The sixth to ninth embodiments are not limited to this construction. Instead, the inside of the pipes 110 be formed of a groove channel. Alternatively, the pipes can 110 of the second evaporator 19 be formed from Nutenkanälen and the pipes 110 of the first evaporator 15 can be made of smooth channels.

In the above-described embodiments, the defrosting mode becomes by detecting the temperature of the air in the vicinity of the second evaporator 19 with the temperature sensor 22 automatically performed. This is only an example. An automatic control of the defrosting mode can be variably modified. For example, the automatic control of the defrosting mode may be performed by detecting the temperature of the surface of the second evaporator 19 , not the temperature of the air near the evaporator 19 , with the temperature sensor 22 be executed.

Alternatively, the following structure may be adopted: a refrigerant temperature sensor for detecting the temperature of the refrigerant is in the refrigerant passage in the vicinity of the second evaporator 19 provided and the automatic control of the defrosting mode is based on the temperature of the refrigerant in the vicinity of the second evaporator 19 executed. There is a correlation between the temperature of the refrigerant and the pressure of the refrigerant in the vicinity of the second evaporator 19 , Therefore, the following structure can be adopted: a refrigerant pressure sensor for detecting the pressure of the refrigerant in the vicinity of the second evaporator 19 is provided and the automatic control of the defrosting mode based on the pressure of the refrigerant in the vicinity of the second evaporator 19 be executed.

Such a temperature sensor 22 and a refrigerant pressure sensor as mentioned above can not be used either. Instead, after the circuit is started, the defrosting mode may be executed only by predetermined times at predetermined time intervals using the timer function of the electric control unit 21 be carried out automatically.

The above description of the first to ninth embodiments takes as examples cases in which the refrigerant cycle device is used for an air conditioner and refrigerators for vehicles. Instead, the first evaporator 15 in which the refrigerant evaporation temperature is higher, and the second evaporator 19 in which the refrigerant evaporation temperature is low, both are also used to cool a single space to be cooled, e.g. B. the interior of the refrigerator can be used. For example, the following structure may be used: the cold room of the refrigerator is connected to the first evaporator 15 cooled, in which the refrigerant evaporation temperature is higher, and the freezer compartment of the refrigerator is connected to the second evaporator 19 cooled, in which the refrigerant evaporation temperature is lower.

In the example of the ninth embodiment ( 21 ) is the one cooling unit 37 from the first evaporator 15 and the second evaporator 19 built up. Then, the inside of the one cooling apparatus becomes with this cooling unit 37 cooled. Instead, the following structure can be used: the first evaporator 15 and the second evaporator 19 are arranged in different refrigerators and the different refrigerators are connected to the first evaporator 15 or the second evaporator 19 cooled.

In the description of the above embodiments, the kind of the refrigerant is not specified. Any type of refrigerant, including chlorofluorocarbons, HC alternatives for chlorofluorocarbons, and carbon dioxide (CO ₂ ) may be used as long as it is applicable to vapor compression refrigerant circuits.

The chlorofluorocarbon mentioned here is a generic name for organic compounds consisting of carbon, fluorine, chlorine and hydrogen and is commonly used as a refrigerant. Fluorocarbon refrigerant includes HCFC (hydrochlorofluorocarbon) refrigerant, HFC (hydrofluorocarbon) refrigerant, and the like. These refrigerants are called alternatives to chlorofluorocarbon because they do not destroy the ozone layer.

HC (hydrocarbon) refrigerant is a refrigerant substance that contains hydrogen and carbon and occurs in nature. The HC refrigerant includes, for example, R600a (isobutane), R290 (propane), and the like.

In the above-described sixth to ninth embodiments, the displacement of the variable displacement compressor becomes 12 with the electrical control unit 21 controlled to the refrigerant output capacity of the compressor 12 to control. Instead, you can also use a compressor with fixed displacement for the compressor 12 be used. In this case, the operation of the compressor with fixed displacement 12 with an electromagnetic clutch on / off. Such is the ratio of the on / off operation of the compressor 12 controlled and the refrigerant discharge capacity of the compressor 12 is controlled by it. If an electric compressor for the compressor 12 can be used, its refrigerant discharge capacity by controlling the speed of the electric compressor 12 to be controlled.

In the above embodiments, a variable flow ejector may be used for the ejector 14 be used. This ejector detects the degree of superheat of the refrigerant at the outlet of the first evaporator 15 and represents the area of the refrigerant passage in the nozzle portion 14a the ejector pump 14 to control a flow rate of the refrigerant in the ejector. In this case, the pressure of the nozzle section 14a ejected refrigerant can be controlled so that the flow rate of the ejector into the ejector 14 aspirated vapor-phase refrigerant can be controlled.

In the above embodiments, each evaporator is 15 . 19 designed as an indoor heat exchanger as a user-side heat exchanger. However, the construction of the above embodiments may be applied to circuits in which an outdoor heat exchanger called a non-user side heat exchanger or the heat source side heat exchanger for each above-mentioned evaporator 15 . 19 is used.

For example, the above embodiments may also be used for circuits called heat pumps. Such circuits include refrigerant circuits for heating in which each evaporator is constructed as an outdoor heat exchanger and a condenser is constructed as an indoor heat exchanger; as well as refrigerant circuits for supplying hot water, in which the water passes through the radiator 13 is heated.

Such changes and modifications are of course within the scope of the present invention as defined by the appended claims.

Claims (22)

Refrigerant cycle device, with a compressor ( 12 ), which sucks and compresses a refrigerant; a cooler ( 13 ) for cooling the high pressure hot gas refrigerant discharged from the compressor; an ejector pump ( 14 ) having a nozzle section ( 14a ) for decompressing and expanding the refrigerant downstream of the radiator, a refrigerant suction port ( 14c ) for sucking the refrigerant through a high-speed flow of the refrigerant discharged from the nozzle portion and a pressure-increasing portion (Fig. 14b ) for mixing and pressurizing the high-velocity discharged refrigerant and the refrigerant sucked through the refrigerant suction port; a first evaporator ( 15 ) for vaporizing the effluent from the ejector refrigerant; a first channel section ( 17 . 36 ) for guiding the refrigerant to the refrigerant suction port; a throttling unit ( 18 ) disposed in the first passage portion and decompressing the refrigerant flowing in the first passage portion; a second evaporator ( 19 ) disposed in the first passage portion in a refrigerant flow downstream of the throttle unit for evaporating the refrigerant; a bypass channel section ( 23 ) for directing the hot gas refrigerant discharged from the compressor into the second evaporator; a bypass opening / closing unit ( 24 ) provided in the bypass passage portion for opening and closing the bypass passage portion, the bypass opening / closing unit having a throttle opening degree when opened; a second channel section ( 25 branched from the bypass passage portion in a refrigerant flow downstream of the bypass opening / closing unit, the hot gas refrigerant flowing in the bypass passage portion through the second passage portion to the first evaporator; and a first flow control unit ( 26a . 26b . 26c ) provided in the second passage section to prevent refrigerant flow from a first evaporator side to a second evaporator side through the second passage section. Refrigerant cycle device according to claim 1, wherein the first channel section is a branch channel ( 17 ) branching in a refrigerant flow from the radiator from an upstream side of the nozzle portion of the ejector to guide the refrigerant from the radiator to the refrigerant suction port of the ejector. A refrigerant cycle device according to claim 1, further comprising a gas / liquid separator (10). 35 ) separating the refrigerant discharged from the first evaporator into vapor refrigerant and liquid refrigerant which collects liquid refrigerant therein and discharges the vapor refrigerant to a refrigerant suction side of the compressor, the first passage portion communicating with a communication passage (FIG. 36 ) connecting a liquid refrigerant outlet portion of the gas-liquid separator with the refrigerant suction port. Refrigerant cycle device according to one of claims 1 to 3, wherein the first flow control unit comprises a check valve ( 26a ), which is arranged to only a refrigerant flow from the Bypass channel section ( 23 ) to the first evaporator through the second channel section (FIG. 25 ) to allow. Refrigerant cycle device according to one of claims 1 to 3, wherein the first flow control unit a switching valve ( 26b ), which is used to open and close the second channel section ( 25 ) is arranged. The refrigerant cycle device according to claim 5, wherein the switching valve is opened when the bypass opening / closing unit is opened and closed when the bypass opening / closing unit is closed. Refrigerant cycle device according to one of claims 1 to 3, wherein the first flow control unit comprises a flow adjustment valve ( 26c ) which is arranged to be brought into a closed state and to regulate a flow amount of the refrigerant in accordance with its valve opening degree which is adjustable. A refrigerant cycle device according to claim 7, further comprising an inlet side temperature detector ( 27 ) arranged to directly or indirectly detect a refrigerant temperature on a refrigerant inlet side of the first evaporator; and an outlet-side temperature detector ( 28 ) arranged to directly or indirectly detect a refrigerant temperature on a refrigerant outlet side of the second evaporator, the flow adjusting valve 26c ) is brought into the closed state when the bypass opening / closing unit is closed, and when the bypass opening / closing unit ( 24 ) is opened, the flow adjustment valve further increases its valve opening degree when passing through the inlet side temperature detector ( 27 ) detected refrigerant temperature lower than that by the outlet-side temperature detector ( 28 ) is the detected refrigerant temperature, and the flow adjustment valve ( 26c ) further reduces its valve opening degree when passing through the inlet side temperature detector ( 27 ) detected refrigerant temperature higher than that by the outlet side temperature detector ( 28 ) is detected refrigerant temperature. Refrigerant cycle device according to one of claims 1 to 8, further comprising a third channel section ( 29 ) coming from the first channel section ( 17 ) in a refrigerant flow from the second evaporator at a position downstream of the second evaporator ( 19 Branched to direct the refrigerant flow from the second evaporator to the first evaporator; and a second flow control unit ( 30 ) in the third channel section ( 29 ) is arranged to a refrigerant flow from the first evaporator ( 15 ) to the second evaporator ( 19 ) through the third channel section ( 29 ) to prevent. Refrigerant cycle device according to claim 9, wherein the second flow control unit comprises a check valve ( 30a ) arranged to allow only a flow of refrigerant from the second evaporator to the first evaporator through the third passage section. The refrigerant cycle device according to claim 9, wherein the second flow control unit is a switching valve arranged to open and close the third passage portion. The refrigerant cycle device according to claim 11, wherein the switching valve is opened when the bypass opening / closing unit is opened and closed when the bypass opening / closing unit is closed. The refrigerant cycle device according to claim 9, wherein the second flow control unit is a flow adjusting valve arranged to be brought into a closed state and to regulate a flow amount of the refrigerant in accordance with its valve opening degree which is adjustable. Refrigerant cycle device according to one of claims 1 to 13, further comprising a channel opening / closing unit ( 31 ) arranged to open and close a refrigerant passage connected to a refrigerant inlet or a refrigerant outlet of the radiator, the channel opening / closing unit (FIG. 31 ) is closed when the bypass opening / closing unit ( 24 ) is opened. Refrigerant cycle device according to one of claims 3 to 14, further comprising a throttle opening / closing unit ( 32 ) disposed in the communication passage for opening and closing a refrigerant passage connected to a refrigerant inlet or a refrigerant outlet of the throttle unit, the throttle opening / closing unit being closed when the bypass opening / closing unit (FIG. 24 ) is opened. The refrigerant cycle device according to any one of claims 1 to 15, wherein the first evaporator and the second evaporator are constructed so that a flow resistance of the refrigerant flowing in the second evaporator is larger than that of the refrigerant flowing in the first evaporator. Refrigerant cycle device, with a compressor ( 12 ), which sucks and compresses a refrigerant; a cooler ( 13 ) for cooling the high pressure hot gas refrigerant discharged from the compressor; an ejector pump ( 14 ) having a nozzle section ( 14a ) for decompressing and expanding the refrigerant downstream of the radiator and a refrigerant suction port ( 14c ) for sucking the refrigerant by a high-speed flow of the refrigerant ejected from the nozzle portion; a first evaporator ( 15 ) for vaporizing the effluent from the ejector refrigerant; a branch channel section ( 17 ) branched from an upstream side of the nozzle portion and connected to the refrigerant suction port of the ejector pump; a throttling unit ( 18 ) located in the branch channel section ( 17 ) and decompresses the refrigerant flowing in the branch passage section; a bypass channel section ( 23 ) for directing the hot gas refrigerant discharged from the compressor into a second evaporator; and a bypass opening / closing unit ( 24 ) disposed in the bypass passage portion for opening and closing the bypass passage portion, the first evaporator and the second evaporator being constructed so that a flow resistance of the refrigerant flowing in the second evaporator is larger than that of the refrigerant flowing in the first evaporator. A refrigerant cycle device according to claim 17, wherein the first evaporator comprises a plurality of first tubes (12). 110 ), in which the refrigerant flows; the second evaporator several second tubes ( 110 ), in which the refrigerant flows; each first tube and each second tube in a channel cross-sectional area therein are identical; and the second tubes of the second evaporator have a tube number smaller than that of the first tubes of the first evaporator. A refrigerant cycle device according to claim 17, wherein the first evaporator comprises a plurality of first tubes (12). 110 ), in which the refrigerant flows; the second evaporator several second tubes ( 110 ), in which the refrigerant flows; the first tubes of the first evaporator and the second tubes of the second evaporator are of identical tube length; and all second tubes of the second evaporator have therein a channel cross-sectional area smaller than that of all the first tubes of the first evaporator. A refrigerant cycle device according to claim 17, wherein the first evaporator comprises a plurality of first tubes (12). 110 ), in which the refrigerant flows; the second evaporator several second tubes ( 110 ), in which the refrigerant flows; all first tubes of the first evaporator and all second tubes of the second evaporator of identical channel cross-sectional area therein; and all the second tubes of the second evaporator have a tube length larger than that of the first tubes of the first evaporator. A refrigerant cycle device according to claim 17, wherein the first evaporator comprises a plurality of first tubes (12). 110 ), in which the refrigerant flows; the second evaporator several second tubes ( 110 ), in which the refrigerant flows; all first tubes of the first evaporator and all second tubes of the second evaporator of identical channel cross-sectional area therein; and the second tubes of the second evaporator have groove channels therein and the second tubes of the first evaporator have shallow channels therein. The refrigerant cycle device according to any one of claims 17 to 21, wherein the bypass opening / closing unit opens the bypass passage portion in a defrosting mode in which a defrosting operation of at least the second evaporator is performed.

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