DE102006058877A1 - Ejector pump-cooling circuit device, has valve unit that makes flow quantity of cooling agent, that flows in evaporation apparatus, to be more than that in normal condition of high pressure cooling unit, when pressure abnormality is found - Google Patents

Abstract

The device (10) has an evaporation apparatus (17), which transfers an evaporated cooling agent to a cooling agent suction opening (13b). A valve mechanism (16a) varies the flow quantity of the cooling agent that flows into the apparatus. A pressure sensor (22) detects the pressure abnormality of the high pressure cooling agent upstream of a nozzle section. A valve unit makes the flow quantity that flows in the evaporation apparatus, to be more than that in a normal condition of a high pressure cooling agent, when the sensor detects the pressure-abnormality. An independent claim is also included for a control method of an ejector pump-cooling circuit device.

Description

FIELD OF THE INVENTION

The The present invention relates to an ejector-type refrigerant cycle device with an ejector pump and a control method of an ejector refrigerant cycle device.

BACKGROUND THE INVENTION

US Patent No. 6,837,069 (corresponding to JP-A-2004-53028) describes an ejector-type refrigeration cycle device, which is constructed so that they have an unusually strong rise in a high pressure side refrigerant pressure avoids the reliability a refrigerant pipe and of functional parts that the high-pressure side refrigerant pressure of the circle received, secure.

In the ejector refrigerant cycle device of U.S. Patent No. 6,837,069 (corresponding to JP-A-2004-53028) is a Branching point for branching a high-pressure refrigerant flow at an upstream Side of a nozzle section of a Ejector provided, is a bypass channel to relieve a High-pressure refrigerant to a portion between a downstream side of an evaporator and a refrigerant suction port of Ejector pump provided by this branching point, and is in this bypass channel arranged a mechanical control valve which is opened, when the high-pressure side refrigerant pressure upstream of the nozzle section a certain pressure condition (e.g., not less than about 10 MPa at a refrigerant temperature from 40 ° C) Fulfills.

According to the above Construction, the control valve is opened when the high-pressure side Refrigerant pressure fulfills the specific condition around the high pressure refrigerant upstream of the nozzle section to Position between the downstream Side of an evaporator and the refrigerant suction via the Bypass channel to relieve, causing an unusually strong increase in the high-pressure side Refrigerant pressure of the circle can be avoided.

at U.S. Patent No. 6,837,069 (equivalent to JP-A-2004-53028) described ejector refrigerant cycle device However, because of the high pressure refrigerant to the downstream Side of the evaporator is relieved when the high-pressure side Refrigerant pressure meets the specific pressure condition, the pressure of the high-pressure side refrigerant to the evaporator exercised. For this reason, the evaporator must be resistant to the Pressure of high pressure refrigerant have, what in an enlargement of the Evaporator and a boost the cost results. Accordingly, become the size and the cost the entire ejector refrigerant cycle device elevated.

SUMMARY THE INVENTION

In In view of the above problems, it is an object of the present Invention, an ejector-type refrigerant cycle device to provide the exercise the pressure of the high-pressure side refrigerant to an evaporator prevent and an unusual can avoid strong increase in the pressure of the high-pressure side refrigerant.

It Another object of the present invention is a control method an ejector-type refrigerant cycle device provided.

According to one Aspect of the present invention includes an ejector-type refrigerant cycle device a compressor that is a refrigerant aspirates, compresses and dispense a cooler that absorbs heat from the compressor refrigerant radiates, and an ejector, which has a nozzle section for reducing the refrigerant pressure downstream of the radiator, to the refrigerant expand, and a refrigerant suction port, from the the refrigerant by a high-speed refrigerant flow discharged from the nozzle portion is sucked. Here, the ejector mixes the from sucked the refrigerant suction port refrigerant and the refrigerant discharged from the nozzle portion and reduces the speed of the mixed refrigerant, so as to increase his pressure. The ejector refrigerant cycle device contains Further, an evaporator which evaporates the refrigerant and the evaporated refrigerant leads to the refrigerant suction port, a Flow rate change unit, which changes a refrigerant flow amount flowing into the evaporator, and a Druckanomalie-detecting device that a Druckanomalie a high pressure side refrigerant pressure upstream of the nozzle section detected. In the ejector refrigerant cycle device the compressor sucks the refrigerant downstream of the ejector, and the flow rate changing unit makes the in flowing the evaporator flow rate greater than those in a normal pressure state of the high-pressure side refrigerant, when the printing abnormality detecting means detects the printing abnormality.

Because the flow amount changing unit makes the refrigerant flow amount flowing into the evaporator larger than that in the normal pressure state of the high-pressure side refrigerant when the pressure abnormality detecting means detects the pressure abnormality, the flow amount of the refrigerant into the refrigerant suction port is suctioned th refrigerant increases. Here, the normal pressure state of the high-pressure refrigerant is a state in which the pressure-abnormality detecting means detects no pressure abnormality.

If the flow rate in the refrigerant suction of the Ejector pump sucked refrigerant gets bigger, becomes in the speed energy of the high-speed refrigerant flow discharged from the nozzle portion for sucking the refrigerant consumed amount of energy greater, thereby the speed of the high-speed refrigerant flow decreases.

Because the flow rate the sucked refrigerant, slower relative to the high velocity refrigerant flow flow rate is, gets bigger, also becomes the flow velocity of the flowing in the diffuser section mixed refrigerant lower.

Of the Diffuser section converts the kinetic energy of the mixed Refrigerant stream in pressure energy to increase the pressure of the refrigerant. Therefore is when the velocity of the mixed flowing into the diffuser section refrigerant becomes smaller, and the pressure increasing amount of the refrigerant lower in the diffuser section. This will reduce the pressure of the the ejector outflowing refrigerant lower.

Out For this reason, the pressure of the ejected from the ejector and decreases through the compressor sucked refrigerant and the pressure of the high pressure side refrigerant may in the ejector-type refrigeration cycle device be reduced. As a result, the pressure of the high-pressure side refrigerant becomes not exerted on the evaporator, and an unusually strong Increase in the high pressure side refrigerant pressure can be avoided.

Further vaporizes a predetermined amount of refrigerant in the evaporator, even if the evaporator refrigerant flow amount rises to a heat absorbing effect to show. Therefore, the ejector-type refrigerant cycle device can perform a cooling operation even at the time of avoiding an unusually sharp rise in the high pressure side refrigerant pressure carry out. Here, the refrigerant flow amount be a mass flow rate of the present invention.

To the For example, a memory can be used to disconnect the ejector outflowing refrigerant in steam refrigerant and liquid Refrigerant in a liquid refrigerant channel be arranged so that the liquid refrigerant from the store flows into the evaporator. In this case, the Flow rate change unit in the liquid refrigerant channel arranged.

alternative For example, a branch channel may be provided to be from one point between a downstream Side of the radiator and an upstream one Side of the nozzle section Branched and with the refrigerant suction of the Ejector pump is connected. In this case, the flow amount changing unit be arranged in the branch channel.

The Pressure anomaly detection means may be provided such that when a high pressure side refrigerant pressure upstream of the nozzle section becomes not less than a predetermined value, the pressure abnormality detecting means recorded the pressure anomaly. Alternatively, the pressure abnormality detecting means be provided so that when the pressure increase amount per unit time of the high-pressure side refrigerant on the upstream Side of the nozzle section becomes not less than a predetermined amount, the pressure anomaly detecting means recorded the pressure anomaly.

In addition, can the flow rate change unit be a variable throttle mechanism which is adapted to a area a refrigerant passage to change. In this case, the flow amount changing unit the flowing into the evaporator refrigerant decompress.

According to one Another aspect of the present invention includes a control method of an ejector-type refrigerant cycle device with an ejector, a step of detecting a pressure anomaly a high pressure side refrigerant upstream of a nozzle section the ejector and a step of reducing the pressure increase degree in the diffuser section the ejector opposite a normal pressure state of the high-pressure refrigerant. Therefore, if the pressure anomaly is detected, the pressure of the high-pressure side refrigerant be reduced, thereby preventing the pressure of the high-pressure side refrigerant exerted on the evaporator will, and an unusual strong increase in the pressure of the high-pressure side refrigerant is avoided.

To the Example, reducing by raising one in the evaporator, the one with the refrigerant suction of the Ejector pump connected refrigerant outlet has, flowing refrigerant amount greater than those are performed in the normal pressure state of the high-pressure refrigerant.

SUMMARY THE DRAWINGS

Other tasks and benefits of the present The invention will be better understood from the following detailed description of preferred embodiments taken in conjunction with the accompanying drawings.

1 Fig. 10 is a general construction diagram of an ejector refrigerant cycle device of a first embodiment of the present invention.

2 FIG. 10 is a flowchart to show the control of a variable throttle mechanism of a climate control unit of the first embodiment. FIG.

3 Fig. 10 is a general construction diagram of an ejector refrigerant cycle device of a second embodiment of the present invention.

DETAILED DESCRIPTION THE PREFERRED EMBODIMENTS

(First embodiment)

In this embodiment becomes a refrigerant (e.g., carbon dioxide) as a refrigerant an ejector-type refrigerant cycle device used in which a high-pressure side refrigerant pressure higher than a supercritical Pressure is. Therefore, the ejector refrigerant cycle device of this embodiment forms a supercritical Cooling circuit.

First a compressor sucks 11 in an ejector-type refrigerant cycle device 10 refrigerant, compresses and discharges it, and increases the pressure of the refrigerant to a supercritical pressure in this embodiment. This compressor 11 has a driving force transmitted thereto from a vehicle engine (not shown) via a pulley and a belt to thereby be rotated and driven. In addition, in this embodiment, a well-known swash plate variable displacement compressor, which can variably and steplessly control an output volume by a control signal, is used as the compressor 11 used.

Here, the discharge volume means the geometric volume of a working space in which refrigerant is sucked and compressed, and specifically, the cylinder volume between the top dead center and the bottom dead center of the stroke of a piston in the compressor 11 , By varying the output volume, the output capacity of the compressor 11 be set. Changing the output volume of the compressor 11 is controlled by controlling the pressure Pc one in the compressor 11 formed swash plate chamber (not shown), so as to change the inclination angle of a swash plate and to change the stroke of the piston performed.

The pressure Pc of the swash plate chamber is changed by changing a ratio of a refrigerant discharge pressure Pd to a refrigerant suction pressure Ps by means of an electromagnetic volume control valve 11a in the compressor 11 controlled. The electromagnetic volume control valve 11a is determined by the output signal of a climate control unit to be described later 20 driven. This allows the compressor 11 change the output volume (displacement) continuously in a range of about 0% to 100%.

Besides, the compressor can 11 because of the compressor 11 can change the discharge volume infinitely in a range of about 0% to 100% by bringing the discharge volume to about 0% in an operation stop state. Therefore, this embodiment employs a clutchless construction in which the rotating shaft of the compressor 11 always coupled via the pulley and the belt to the vehicle engine.

The variable displacement compressor 11 can also be provided so that energy from the vehicle engine to the compressor 11 transmitted via an electromagnetic clutch. If a compressor with fixed displacement as a compressor 11 is used, it is also recommended that an on / off control of the intermittent operation of the compressor is performed by an electromagnetic clutch to control the ratio of the on-operation to the off-operation of the compressor. Also in this case, the discharge volume of the refrigerant of the compressor can be effectively controlled.

A cooler 12 is with a refrigerant downstream side of the compressor 11 connected. The cooler 12 is a heat exchanger that transfers heat between the compressor 11 discharged high pressure refrigerant and by a blower fan 12a blown outside air (ie, air outside a vehicle compartment) to cool the high-pressure refrigerant. The blower fan 12a is one by a motor 12b powered, electrically operated fan. Further, the engine becomes 12b by a climate control unit to be described later 20 output control voltage is rotated and driven.

This embodiment forms a supercritical cooling circuit, so that the refrigerant in the radiator 12 does not condense and radiate heat because it is kept in a supercritical pressure state.

An ejector pump 13 is with the refrigerant downstream side of the radiator 12 connected. The ejector pump 13 contains a nozzle section 13a that's out of the cooler 12 flowing refrigerant throttles so as to reduce the pressure of the refrigerant and to expand the refrigerant in an isentropic manner; and a refrigerant suction port 13b , which is arranged so that it communicates with the jet opening of the nozzle section 13a communicates and the refrigerant downstream of an evaporator to be described later 17 sucks.

Next contains the ejector 13 a mixing section 13c located downstream of the nozzle section 13a and the refrigerant suction port 13b is arranged and a high-speed refrigerant flow from the nozzle portion 13a with that of the refrigerant suction port 13b sucked refrigerant mixed; and a diffuser section 13d , which is downstream of the mixing section 13c is arranged and reduces the speed of the refrigerant flow, so as to increase the pressure of the refrigerant.

This diffuser section 13d is formed in such a shape that the area of the refrigerant passage gradually becomes larger, and has a function of reducing the speed of the refrigerant flow so as to increase the pressure of the refrigerant, that is, a function of converting the speed energy of the refrigerant into its pressure energy.

A store 14 is with the refrigerant downstream side of the diffuser section 13d the ejector pump 13 connected. The memory 14 is formed in the shape of a container and is a vapor / liquid separation unit. The memory 14 separates the refrigerant in a mixed vapor / liquid state emerging from the diffuser section 13d the ejector pump 13 has flowed through a density difference in a vapor-phase refrigerant and a liquid-phase refrigerant. Thus, the vapor-phase refrigerant becomes on the upper side in the vertical direction of the interior of a tank part of the memory 14 collected, and the liquid-phase refrigerant is collected in the lower area in the vertical direction.

Next is a vapor phase refrigerant outlet 14a in the upper part of the container-shaped storage 14 intended. The vapor-phase refrigerant outlet 14a is with the refrigerant suction side of the compressor 11 connected. On the other hand, a liquid-phase refrigerant outlet 14b in the bottom of the container part of the store 14 intended. The liquid phase refrigerant outlet 14b is with a liquid phase refrigerant channel 15 connected.

This liquid-phase refrigerant channel 15 is a refrigerant piping for connecting the liquid-phase refrigerant outlet 14b of the memory 14 with the refrigerant suction port 13b the ejector pump 13 , In the liquid phase refrigerant channel 15 are a variable throttle mechanism 16 and an evaporator 17 arranged. The variable throttle mechanism 16 reduces the pressure of the memory 14 flowing liquid phase refrigerant to the evaporation pressure of the refrigerant in the evaporator 17 adjust. In this embodiment, the variable throttle mechanism 16 an electrical variable throttle mechanism triggered by the control signal of the climate control unit 20 is controlled.

For example, the variable throttle mechanism 16 a flow rate adjustment valve that includes a valve mechanism 16a which is configured to change the passage area of the refrigerant, and one by one from the climate control unit 20 output control signal (pulse signal) rotated and driven stepping motor 16b contains. When the stepper motor 16 is rotated, the valve body of the valve mechanism 16a shifted to adjust the passage area of the refrigerant continuously.

This is how the valve mechanism forms 16a the variable throttle mechanism 16 a flow amount changing unit for changing one into the evaporator 17 flowing evaporator refrigerant flow amount Ge, and the stepping motor 16b forms a drive means for varying the passage area of the refrigerant of the valve mechanism 16a ,

The evaporator 17 is a heat exchanger located on the refrigerant downstream side of the variable throttle mechanism 16 in the liquid phase refrigerant channel 15 is arranged and heat between the low pressure refrigerant, its pressure through the variable throttle mechanism 16 has been reduced, and by the blower fan 17a exchanged blown air. The low pressure refrigerant in the evaporator 17 absorbs heat from the air to cool the air in a room to be cooled.

In addition, the blower fan 17a an electric fan powered by a motor 17b is driven. The motor 17b is by a climate control unit to be described later 20 output control voltage is rotated and driven. Further, as described above, the downstream side of the evaporator 17 with the refrigerant suction port 13b the ejector pump 13 connected, so that the refrigerant from the evaporator 17 into the refrigerant suction port 13b the ejector pump 13 is sucked.

Next, an electric control operation of this embodiment will be described. The climate control unit 20 It is constructed of a well-known microcomputer having a CPU, a ROM, a RAM and the like and its peripheral circuits, and performs various kinds of calculations and processing on the basis of control programs stored in the ROM to the operations of the above various types of devices 11a . 12b . 16b . 17b to control.

Further, the climate control unit 20 Measuring signals from a group of different types of sensors and various operating signals from a control panel (not shown) entered. In particular, the group of sensors includes a temperature sensor 21 for detecting a refrigerant temperature Tev downstream of the evaporator 17 , a pressure sensor 22 for detecting a refrigerant pressure Pev downstream of the evaporator 17 and a pressure sensor 23 for detecting a refrigerant pressure Pnoz upstream of the nozzle portion 13a , Further, the operation panel is provided with an operation switch for operating a cooling unit and a temperature setting switch for setting a temperature in the space to be cooled (eg, refrigerator).

Next, an operation of the ejector refrigerant cycle device of the above construction will be described. First, when the vehicle engine is in operation, a rotational drive force is applied from the vehicle engine to the compressor 11 transfer. Further, when the operation signal of the operation switch of the climate control unit 20 entered from the control panel, from the climate control panel 20 an output signal to the electromagnetic volume control valve 11a on the basis of the pre-stored control program.

The output volume (displacement) of the compressor 11 is determined by this output signal, and the compressor 11 sucks the vapor-phase refrigerant from the vapor-phase refrigerant outlet 14a of the memory 14 and compresses the vapor-phase refrigerant in a supercritical state, and then outputs the vapor-phase refrigerant. The refrigerant in the supercritical state, from the compressor 11 spent, flows into the radiator 12 and is cooled by the outside air. Next flows from the radiator 12 outflowing refrigerant into the nozzle section 13a the ejector pump 13 ,

That in the nozzle section 13a the ejector pump 13 flowing refrigerant has its pressure in the nozzle section 13a reduces, bringing it into a two-phase state of vapor and liquid. The pressure energy of the high-pressure refrigerant is through the nozzle portion 13a converted into velocity energy, whereby the refrigerant is brought into a high-speed refrigerant flow and out of the jet opening of the nozzle portion 13a is ejected. The refrigerant downstream of the evaporator 17 is from the refrigerant suction port 13b by a pressure drop near the jet opening of the nozzle section 13a is generated at this time, sucked.

That of the nozzle section 13a discharged refrigerant and that of the refrigerant suction port 13b sucked refrigerant are mixed with each other in the mixing section 13c downstream of the nozzle section 13a mixed and flow into the diffuser section 13d , In this diffuser section 13d the speed energy of the refrigerant is converted into pressure energy by enlarging the passage area, so that the pressure of the refrigerant downstream of the ejector increases the flow velocity of the refrigerant into the diffuser section 13d flowing refrigerant is increased.

That from the diffuser section 13d the ejector pump 13 escaping refrigerant flows into the memory 14 and is separated into vapor-phase refrigerant and liquid-phase refrigerant. The vapor phase refrigerant in the store 14 will be back in the compressor 11 sucked and compressed by him.

On the other hand, the liquid-phase refrigerant flows in the memory 14 by the suction effect of the ejector pump 13 into the liquid phase refrigerant channel 15 , Through the variable throttle mechanism 16 the flow rate of the liquid phase refrigerant is adjusted and its pressure is reduced, and it flows into the evaporator 17 , When the liquid-phase refrigerant in the evaporator 17 vaporizes, the liquid phase refrigerant absorbs heat from the air in the refrigerator (ie the space to be cooled), through the blower fan 17a is blown, whereby the air is cooled in the refrigerator.

That from the evaporator 17 escaping refrigerant is in the refrigerant suction port 13b sucked and with one of the nozzle section 13a ejected high-velocity refrigerant flow mixed.

The climate control unit 20 in this embodiment controls the stepper motor 16b the variable throttle mechanism 16 so as to the passage area of the refrigerant of the valve mechanism 16a to change. The operation of the climate control unit 20 is based on a in 2 illustrated flowchart described. First, in step S1, the control signals of a refrigerant temperature Tev downstream of the evaporator 17 , a refrigerant pressure Pev downstream of the evaporator 17 and a refrigerant pressure Pnoz stream on the nozzle section 13a read.

When next is determined in step S2 on the basis of Pnoz read in step S1 determines whether the high-pressure side refrigerant pressure of the circuit unusual is high or not. In particular, it is determined whether the detected Refrigerant pressure Pnoz not higher as a reference high-pressure refrigerant pressure KPnoz is or not.

Here, the reference high-pressure refrigerant pressure KPnoz is a preset value to determine that a high-pressure side refrigerant pressure upstream of the nozzle portion 13a in a the compressive strength value of the refrigerant piping and the functional parts (for example, radiator 121 that the high-pressure side refrigerant pressure upstream of the nozzle portion 13a receive, non-passing area becomes unusually high.

Therefore, if it is determined in step S2 that Pnoz ≦ KPnoz, it is determined that the high-pressure side refrigerant pressure of the circuit is not in the abnormal pressure state, and the control routine proceeds to step S3. If it is not determined that Pnoz ≤ KPnoz, it is determined that the high-pressure side refrigerant pressure of the circuit is in the abnormal pressure state, and the control routine proceeds to step S5. For this reason, in this embodiment, step S2 is a determination means for determining whether or not the high-pressure side refrigerant pressure of the circuit is in abnormal pressure state on the basis of the measurement value of the pressure sensor 23 ,

In step S3, a normal operation control is performed because the high-pressure side refrigerant pressure is not in an abnormal pressure state. In this normal operation control, the refrigerant passage area of the valve mechanism becomes 16a controlled in such a way that the refrigerant downstream of the evaporator 17 has a set degree of overheating.

For example, the superheat degree of the refrigerant becomes downstream of the evaporator 17 on the basis of the refrigerant temperature Tev and the refrigerant pressure Pev, which are read in step S1, by the climate control unit 20 calculated, and a control signal (pulse signal) is sent to the stepper motor 16b is output so that this superheat degree reaches a preset value.

By controlling the superheat degree of the refrigerant downstream of the evaporator 17 to a predetermined degree of superheat, the liquid-phase refrigerant absorbs when it enters the evaporator 17 flowing liquid phase refrigerant evaporates heat from that through the blower fan 17 blown air to cool the blown air. Therefore, it can be prevented that in the evaporator 17 flowing evaporator refrigerant flow amount Ge is unnecessarily increased.

For this reason, the flow rate of the refrigerant into the Kältemittelansaugöffnung 13b the ejector pump 13 sucked refrigerant is not unnecessarily increased, whereby the flow rate of one by mixing the sucked refrigerant with the nozzle portion 13a ejected high-speed refrigerant flow generated mixed flow is not reduced. The velocity energy of the mixed stream becomes in the diffuser section 13d converted into pressure energy to the pressure of the refrigerant downstream of the ejector 13 to increase.

Thus, the refrigerant evaporation pressure of the evaporator becomes 17 that with the refrigerant suction port 13b is lower than the refrigerant pressure downstream of the ejector 13 , Even if the refrigerant evaporation temperature in the evaporator 17 is set to a cooling temperature suitable for freezing (eg from -5 ° C to 5 ° C), the pressure of the by the compressor 11 sucked refrigerant higher than the refrigerant evaporation pressure in the evaporator 17 be made. As a result, the drive power of the compressor 11 reduced and the efficiency of the circuit can be improved.

If the normal operation control is performed in step S3, the control routine proceeds to step S4, and then returns Control routine back to step S1, after a set Time T (e.g., a unit of time) has elapsed.

If it is not determined in step S2 that Pnoz ≦ KPnoz, it is next determined that the high-pressure side refrigerant pressure of the circuit is in the abnormal pressure state, and the control routine proceeds to step S5. In step S5, the climate control unit outputs 20 a control signal (pulse signal) to the stepping motor 16b out to the refrigerant passage area of the valve mechanism 16a to increase a certain value, and then the routine proceeds to step S6.

Next, Pnoz is read again in step S6, and the control routine proceeds to step S7. In step S7, it is determined whether or not Pnoz is smaller than the reference high-pressure refrigerant pressure KPnoz-α set in advance. Here, α is a predetermined value for setting a hysteresis width so as to prevent the control of the refrigerant passage area of the valve mechanism 16a lags.

In particular, it is determined in step S7 whether Pnoz ≤ KPnoz-α or not. When it is determined that Pnoz ≦ KPnoz-α, it is determined that the high-pressure side refrigerant pressure comes out of the abnormal pressure state, and the control routine proceeds to step S4. That is, when Pnoz ≤ KPnoz-α in step S7, it is determined that the high-pressure side refrigerant pressure becomes the normal state. On the other hand, if it is not determined that Pnoz ≦ KPnoz-α, it is determined that the high-pressure side refrigerant pressure is still in the abnormal pressure state, ie, the abnormally high pressure, and the control routine returns to step S5. Therefore, the climate control unit gives 20 a control signal (pulse signal) to the stepping motor 16b out to the refrigerant passage area of the valve mechanism 16a to expand.

In this way the climate control unit controls 20 when it is determined that the high-pressure side refrigerant pressure is in the abnormal pressure state, the stepping motor 16b such that the refrigerant passage area of the valve mechanism 16a is extended. In this case, the in the evaporator 17 flowing evaporator refrigerant flow amount Ge increases. For this reason, the flow rate of the refrigerant into the Kältemittelansaugöffnung 13b the ejector pump 13 sucked refrigerant increased.

Therefore, the flow rate of the mixed refrigerant, which is generated by mixing the drawn refrigerant flow with the high-speed refrigerant flow, is also reduced, so as to also reduce the speed energy of the mixed refrigerant flow to be in the diffuser section 13d in the ejector pump 13 to convert into the pressure energy. In this case, the increasing amount of the refrigerant pressure in the diffuser portion of the ejector becomes 13 reduced. As a result, the pressure of the compressor 11 sucked refrigerant compared to the pressure at the time of normal operation reduced, and the pressure of the compressor 11 refrigerant discharged is also reduced, whereby an unusually large increase in the high-pressure side refrigerant pressure of the circuit can be avoided.

Further, even if the evaporator refrigerant flow amount Ge (refrigerant flow rate) is increased, because a part of the memory 14 in the evaporator 17 flowing liquid phase refrigerant evaporates, this part heat from that of the blower fan 17a can absorb blown air and therefore the blower fan 17a Cool blown air. That is, the circuit can perform a cooling operation even in this abnormal operation control.

In this embodiment, in the normal operation control in which a pressure abnormality in the high-pressure side refrigerant pressure of the circuit is not detected, it is possible to reduce the driving force of the compressor and improve the efficiency of the circuit by increasing the pressure of the compressor 11 to be sucked refrigerant using the pressure increasing function of the diffuser section 13d is increased.

Further, when a pressure abnormality is detected at the high-pressure side refrigerant pressure of the cycle, the evaporator refrigerant flow amount Ge (refrigerant flow rate) is increased, and the abnormal operation control is performed. Accordingly, in the abnormal operation control, it is possible to increase the refrigerant pressure rise in the diffuser section 13d to suppress, while the cooling operation of the circuit is performed, and to avoid the unusually high pressure of the circuit. Therefore, in the ejector-type refrigerant cycle device of this embodiment, the cooling operation can be performed without suppressing the pressure of the high-pressure side refrigerant to the evaporator 12 exercise.

Second Embodiment

In the first embodiment described above, the refrigerant cycle with the liquid-phase refrigerant passage 15 for connecting the liquid-phase refrigerant outlet 14b of the memory 14 with the refrigerant suction port 13b the ejector pump 13 provided, and the variable throttle mechanism 16 and the evaporator 17 are in this liquid-phase refrigerant channel 15 arranged. In the second embodiment, however, as in FIG 3 shown, the liquid-phase refrigerant channel 15 not provided, but it is a branch channel 25 for branching the refrigerant flow at a branching point Z between the downstream side of the radiator 12 and the upstream side of the nozzle portion 13a the ejector pump 13 is positioned provided.

This branch channel 25 is a refrigerant passage for connecting the branch point Z to the refrigerant suction port 13b the ejector pump 13 , In this embodiment, the variable throttle mechanism 16 in the branch channel 25 arranged, and the evaporator 17 is refrigerant downstream of the variable throttle mechanism 16 in the branch channel 25 arranged. The variable throttle mechanism 16 and the evaporator 17 have constructions similar to those described in the first embodiment, respectively. Here, in this embodiment, a confusion with a second evaporator to be described later 26 to avoid the evaporator 17 in the following description, referred to as a first evaporator.

Further, in this embodiment, the second evaporator 26 between the downstream side of the ejector 13 and the memory 14 arranged. The second evaporator 26 is a heat exchanger that transfers heat between the low-pressure refrigerant downstream of the ejector 13 and air in the cold room (room to be cooled, the blower fan 17a is blown, to allow the low pressure refrigerant to absorb heat to cool the air in the cold room.

Further, in this embodiment, the pressure sensor 23 for detecting the refrigerant pressure Pnoz upstream of the nozzle portion 13a arranged upstream of the branch point Z. Of course, the position of the pressure sensor 23 not limited to this position, but it may, for example, between the branch point Z and the nozzle portion 13a to be ordered. In the second embodiment, the other constructions of the ejector refrigerant cycle device may be made similar to those of the first embodiment described above.

Next, the operation of the ejector refrigerant cycle device according to this embodiment will be described. First, just as in the first embodiment, when the vehicle engine is in operation, refrigerant flows in a supercritical state from the compressor 11 in the condenser 12 , whereby the outside air is cooled.

This will continue from the radiator 12 effluent refrigerant at the branch point Z in one in the nozzle section 13a the ejector pump 13 flowing refrigerant flow and one in the branch channel 25 branched refrigerant flow branches. Therefore, in this embodiment, the flow rate of the in the branch channel 25 flowing refrigerant to the evaporator refrigerant flow amount Ge.

That in the nozzle section 13 flowing refrigerant is exactly as in the first embodiment in the nozzle section 13a in the pressure reduces and sucks the refrigerant downstream of the first evaporator 17 from the refrigerant suction port 13b at. Further, the nozzle portion 13a discharged refrigerant and that of the refrigerant suction port 13b sucked refrigerant together in the mixing section 13c mixed and in the diffuser section 13d increases in pressure according to the speed energy of the mixed refrigerant flow.

That from the diffuser section 13d escaping refrigerant flows into the second evaporator 26 , In the second evaporator 26 absorbs this in the nozzle section 13a Low pressure refrigerant reduces heat in the pressure from the blower fan 17a blown air and evaporated. The refrigerant after flowing through the second evaporator 26 flows into the store 14 and is separated into vapor-phase refrigerant and liquid-phase refrigerant. The vapor phase refrigerant in the store 14 is through the compressor 11 sucked and compressed again.

On the other hand, that will be in the branch channel 25 flowing refrigerant through the variable throttle mechanism 16 set in the flow rate and reduced in pressure and flows into the first evaporator 17 , In the first evaporator 17 The low-pressure inflow refrigerant absorbs heat from that from the second evaporator 26 flowing air and evaporates. This is the result of the blower fan 17a blown and through the second evaporator 26 cooled air in the first evaporator 17 further cooled. The refrigerant downstream of the first evaporator 17 is in the refrigerant suction port 13b sucked and with the high-speed refrigerant flow from the nozzle section 13a mixed.

Also in the above construction, the throttle opening degree of the variable throttle mechanism 16 as in the first embodiment, as indicated by the flowchart in FIG 2 shown. That is, in the normal operation control in which a pressure abnormality in the high-pressure side refrigerant pressure of the circuit is not detected, it is possible to control the driving force of the compressor 11 to reduce and improve the efficiency of the circuit by reducing the pressure of the compressor 11 to be sucked refrigerant by means of the pressure increase of the refrigerant in the diffuser section 13d is increased.

Further, when a pressure abnormality is detected in the high-pressure side refrigerant pressure of the cycle, the evaporator refrigerant flow amount Ge is increased. Accordingly, it is possible to increase the pressure of the refrigerant in the diffuser section 13d to suppress, whereby an unusually high pressure of the circle is prevented while the cooling of the circuit is performed. Therefore, on the first evaporator 17 no high pressure applied.

In addition, in this embodiment, the variable throttle mechanism increases 16 because the refrigerant flow at the branch point Z upstream of the nozzle portion 13a is branched, the evaporator refrigerant flow amount Ge and simultaneously reduces the flow rate of the nozzle in the portion 13a flowing refrigerant. As a result, the speed of the diffuser section 13d reduced mixed refrigerant, whereby the pressure increase degree of the refrigerant in the diffuser section 13d is reduced.

(Further embodiments)

• (1) In den obigen Ausführungsbeispielen wird der elektrische variable Drosselmechanismus als variabler Drosselmechanismus 16 benutzt, der die Strömungsrateneinstellfunktion besitzt, aber ein mechanischer variabler Drosselmechanismus kann ebenfalls als variabler Drosselmechanismus 16 mit der Strömungsrateneinstellfunktion verwendet werden.

The present invention is not limited to the above embodiments, but may be variously modified as described below.

• (1) In the above embodiments, the electric variable throttle mechanism becomes a variable throttle mechanism 16 which has the flow rate adjusting function, but a mechanical variable throttle mechanism can also be used as a variable throttle mechanism 16 be used with the flow rate adjustment function.

For example, a pressure transmitting device may be provided that is upstream of the nozzle portion in response to the high-pressure side refrigerant pressure 13a is moved. In this case, the pressure transmission device is constructed from a spring plate or a bellows. In addition, by a resilient means such as a coil spring, a load is applied to the pressure transmitting means from a direction against the force which the pressure transmitting means undergoes from the high-pressure side refrigerant pressure. Thereby, the pressure abnormality detecting means may be configured such that when the high-pressure side refrigerant pressure becomes not less than a predetermined value determined by the elastic means, the pressure transmitting means is shifted.

• (2) Im obigen Ausführungsbeispiel wird in Schritt S2 des durch die Klimasteuereinheit 20 ausgeführten Steuerprogramms eine Druckanomalie erfasst, wenn der Kältemitteldruck Pnoz stromauf des Düsenabschnitts 13a größer als der Referenz-Hochdruck-Kältemitteldruck KPnoz ist. Eine Druckanomalie kann jedoch auch auf der Basis des Erhöhungsmaßes je Zeiteinheit im Kältemitteldruck Pnoz stromauf des Düsenabschnitts 13a erfasst werden.

Further, a valve mechanism of the flow amount changing unit for changing the evaporator refrigerant flow amount Ge may be combined with the variable throttle mechanism so as to expand the refrigerant passage area in accordance with the shift amount of this pressure transmitting device. This construction can mechanically construct the variable throttle mechanism (flow amount change unit) that increases the evaporator refrigerant flow amount Ge as the high-pressure side refrigerant pressure increases.

• (2) In the above embodiment, by the climate control unit in step S2 of FIG 20 executed control program detects a pressure anomaly when the refrigerant pressure Pnoz upstream of the nozzle section 13a greater than the reference high pressure refrigerant pressure KPnoz is. However, a pressure anomaly may also be based on the amount of increase per unit time in the refrigerant pressure Pnoz upstream of the nozzle portion 13a be recorded.

• (3) Im obigen zweiten Ausführungsbeispiel kühlen der erste und der zweite Verdampfapparat 17, 26 den gleichen zu kühlenden Raum (z.B. Luft im Kühlraum). Der erste und der der zweite Verdampfapparat 17, 26 können jedoch auch unterschiedliche Gegenstände oder Räume kühlen, die gekühlt werden sollen.

For example, the discharge side refrigerant pressure of the compressor 12 by an abrupt increase in the speed of the compressor 11 be increased abruptly, even if the actual refrigerant pressure upstream of the nozzle section 13a does not rise to the reference high pressure refrigerant pressure KPnoz. Also in this case, a printing anomaly can be currently detected based on the amount of increase per unit time in Pnoz. This makes it possible to reliably ensure the reliability of the Kältemitterohrleitung and the functional parts.

• (3) In the above second embodiment, the first and second evaporators cool 17 . 26 the same room to be cooled (eg air in the refrigerator). The first and the second evaporator 17 . 26 However, they can also cool different objects or rooms that are to be cooled.

For example, it is possible to use the first evaporator 17 to use for cooling air in the space of a refrigerator for a vehicle and the second evaporator 26 to use for cooling air in a passenger compartment of the vehicle. In this case, it is possible because the outlet side of the first evaporator 17 with the refrigerant suction port 13b the ejector pump 13 is the lowest pressure immediately after reducing the pressure in the nozzle section 13a on the outlet side of the first evaporator 17 exercise and the pressure after increase in the diffuser section 14b as the refrigerant pressure of the second evaporator 26 apply.

Thereby, the refrigerant evaporation pressure (the refrigerant evaporation temperature) of the first evaporator 17 lower than the refrigerant evaporation pressure (the refrigerant evaporation temperature) of the second evaporator 26 be made. Therefore, it is possible to perform a cooling operation in a relatively high temperature range suitable for cooling the passenger compartment by the second evaporator 26 and at the same time a cooling operation in an even lower temperature range, which is suitable for cooling the cooling apparatus, by the first evaporator 17 perform.

• (4) In den obigen Ausführungsbeispielen werden der erste Verdampfapparat 17 und der zweite Verdampfapparat 26 als benutzungsseitige Wärmetauscher zum Kühlen von Luft im Kühlraum, welcher der zu kühlende Raum ist, benutzt, während der Kühler 12 ein Wärmetauscher zum Abstrahlen von Wärme an die Umgebung ist. Im Gegensatz dazu kann die vorliegende Erfindung auch auf einen Aufbau (Wärmepumpenkreis) mit dem ersten Verdampfapparat 17 und dem zweiten Verdampfapparat 26 als Wärmetauscher zum Absorbieren von Wärme von einer Wärmequelle wie beispielsweise der Umgebung und mit dem Kühler 12 als benutzungsseitigen Wärmetauscher zum Heizen von Luft oder Wasser, die ein zu heizender Gegenstand sind, angewendet werden.

Even if the second evaporator 26 downstream of the diffuser section 13d the ejector pump 13 In the first embodiment, it is possible to produce the effect described in the first embodiment.

• (4) In the above embodiments, the first evaporator 17 and the second evaporator 26 as the use side heat exchanger for cooling air in the cold room, which is the space to be cooled, used while the radiator 12 a heat exchanger for radiating heat to the environment. In contrast, the present invention can also be applied to a structure (heat pump cycle) with the first evaporator 17 and the second evaporator 26 as a heat exchanger for absorbing heat from a heat source such as the environment and with the radiator 12 be used as a use side heat exchanger for heating air or water, which are an object to be heated.

• (5) In den obigen Ausführungsbeispielen kann ein Innenwärmetauscher zum Austauschen von Wärme zwischen Hochdruckkältemittel stromab des Kühlers 12 und Niederdruckkältemittel auf der Ansaugseite des Kompressors 11 vorgesehen sein. Gemäß diesem Aufbau wird ein Kältemittel stromab des Kühlers 12 gekühlt, sodass es möglich ist, einen Unterschied in der Enthalpie (Kühlkapazität) des Kältemittels zwischen Kältemitteleinlass und -auslass in jedem des ersten Verdampfapparats 17 und des zweiten Verdampfapparats 26 zu vergrößern.
• (6) In den obigen Ausführungsbeispielen wurde ein Beispiel beschrieben, das Kohlendioxid als Kältemittel benutzt und einen überkritischen Kühlkreis bildet, in dem der hochdruckseitige Kältemitteldruck einen überkritischen Druck übersteigt. Als Kältemittel kann jedoch auch ein Kältemittel auf Fron-Basis oder HC-Basis verwendet werden. Weiter kann die vorliegende Erfindung auch auf einen Fall des Konstruierens eines unterkritischen Dampfkompressions-Kühlkreises angewendet werden, in dem der Hochdruck einen überkritischen Druck nicht übersteigt.
• (7) In den obigen Ausführungsbeispielen wurde eine feste Düse mit einer konstanten Kältemitteldurchgangsfläche als ein Beispiel des Düsenabschnitts 13a gezeigt. Eine variable Ejektorpumpe mit einem variablen Düsenabschnitt, der die Kältemitteldurchgangsfläche einstellen kann, kann jedoch auch als Ejektorpumpe 13 verwendet werden. Als ein Beispiel kann für den variablen Düsenabschnitt zum Beispiel ein Mechanismus eingesetzt werden, bei dem die Position einer in den Durchgang des variablen Düsenabschnitts eingesetzten Nadel durch einen elektrischen Stellantrieb gesteuert wird, um die Kältemitteldurchgangsfläche einzustellen.

In other words, the refrigeration cycle according to the embodiments may be used as a heat pump cycle including the radiator 12 used as a use side heat exchanger (eg, heater).

• (5) In the above embodiments, an indoor heat exchanger for exchanging heat between high-pressure refrigerant downstream of the radiator 12 and low pressure refrigerant on the suction side of the compressor 11 be provided. According to this structure, a refrigerant becomes downstream of the radiator 12 cooled so that it is possible to detect a difference in the enthalpy (cooling capacity) of the refrigerant between the refrigerant inlet and outlet in each of the first evaporator 17 and the second evaporator 26 to enlarge.
• (6) In the above embodiments, an example has been described which uses carbon dioxide as a refrigerant and forms a supercritical refrigerant cycle in which the high-pressure side refrigerant pressure exceeds a supercritical pressure. As refrigerant, however, a refrigerant based on Fron or HC can be used. Further, the present invention can also be applied to a case of constructing a subcritical vapor compression refrigerating cycle in which the high pressure does not exceed a supercritical pressure.
• (7) In the above embodiments, a fixed nozzle having a constant refrigerant passage area became an example of the nozzle portion 13a shown. However, a variable ejector pump having a variable nozzle portion that can adjust the refrigerant passage area may also be used as an ejector 13 be used. As an example, for the variable nozzle portion, for example, a mechanism may be employed in which the position of a needle inserted into the passage of the variable nozzle portion is controlled by an electric actuator to adjust the refrigerant passage area.

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

Claims (14)

Ejector pump refrigeration cycle device, with a compressor ( 11 ) which sucks, compresses and discharges a refrigerant; a cooler ( 12 ), which radiates heat of the refrigerant discharged from the compressor; an ejector pump ( 13 ) having a nozzle section ( 13a ) for reducing a pressure of the refrigerant downstream of the radiator to expand the refrigerant, and a refrigerant suction port (FIG. 13b ), from which a refrigerant is sucked by a high-speed refrigerant flow discharged from the nozzle portion, the ejector mixing the refrigerant sucked from the refrigerant suction port and the refrigerant discharged from the nozzle portion, and reducing the speed of the mixed refrigerant so as to increase its pressure; an evaporator ( 17 ), which vaporizes the refrigerant and the vaporized refrigerant to the refrigerant suction port ( 13b ); a flow rate change unit ( 16a ) which changes a refrigerant flow amount flowing into the evaporator; and a pressure abnormality detecting means (Fig. 23 , S2) detecting a pressure abnormality of a high pressure refrigerant upstream of the nozzle portion, wherein the compressor sucks the refrigerant downstream of the ejector, and wherein, when the pressure abnormality detecting means detects the pressure abnormality, the flow amount change unit increases the refrigerant flow amount flowing into the evaporator larger than that in a normal one Pressure state of the high pressure refrigerant makes. An ejector refrigerant cycle device according to claim 1, further comprising a memory ( 14 ) separating the refrigerant discharged from the ejector into vapor refrigerant and liquid refrigerant; and a liquid refrigerant passage through which the liquid refrigerant flows from the reservoir into the evaporator, the flow amount changing unit being disposed in the liquid refrigerant passage. An ejector-type refrigerant cycle device according to claim 1, further comprising a branch passage (16). 25 ) branched from a point (Z) between a downstream side of the radiator and an upstream side of the nozzle portion and connected to the refrigerant suction port of the ejector, the flow amount changing unit being disposed in the branch passage. Ejector refrigerant cycle device according to one of the claims 1 to 3, in which, when a high-pressure side refrigerant pressure upstream of the nozzle section becomes not less than a predetermined value, the pressure anomaly detecting means Recorded pressure anomaly. An ejector refrigerant cycle device according to any one of claims 1 to 3, wherein, when a Pressure increase amount per unit time of the high pressure refrigerant upstream of the nozzle portion is not less than predetermined value, the pressure anomaly detecting means detects the pressure anomaly. Ejector refrigerant cycle device according to one of the claims 1 to 5, wherein the flow rate changing unit is a variable throttle mechanism which is adapted to a area a refrigerant passage to change. An ejector-type refrigerant cycle device according to any one of claims 1 to 6, further comprising a drive element (10). 16b ) driving the flow amount changing unit to change a refrigerant passage area in the flow amount changing unit; and a control unit ( 20 ), which controls an operation of the driving member, wherein the pressure abnormality detecting means comprises a pressure sensor ( 23 ) for detecting a pressure of the high-pressure refrigerant upstream of the nozzle portion, and determining means (S2) for determining whether or not a measurement value of the pressure sensor corresponds to the pressure abnormality, and wherein if the determination means determines that the measurement value of the pressure sensor corresponds to the pressure abnormality, the control unit controls the driving member so as to expand the refrigerant passage area. An ejector-type refrigerant cycle device according to claim 1, wherein said ejector further includes a mixing portion (16). 13c ), in which the refrigerant discharged from the nozzle portion and the refrigerant sucked from the refrigerant suction port are mixed, and a diffuser portion (FIG. 13d ), which increases the pressure of the mixed refrigerant from the mixing portion, the apparatus further comprising reducing means for reducing a pressure increasing amount of the mixed refrigerant in the diffuser portion, and wherein when the pressure anomaly detecting means detects the pressure abnormality, the reducing means the pressure increasing amount of the mixed refrigerant reduced in the diffuser section relative to the normal pressure state of the high-pressure refrigerant. Ejector refrigerant cycle device according to claim 8, wherein the flow amount changing unit as the reduction means is used. An ejector refrigerant cycle device according to claim 3, further comprising a further evaporator ( 12 ) for vaporizing the refrigerant flowing out of an outlet port of the ejector. Ejector pump refrigeration cycle device, with a compressor ( 11 ) which sucks, compresses and discharges a refrigerant; a cooler ( 12 ), which radiates heat of the refrigerant discharged from the compressor; an ejector pump ( 13 ) having a nozzle section ( 13a ) for reducing a pressure of the refrigerant downstream of the radiator to expand the refrigerant, a refrigerant suction port ( 13b ), of which a refrigerant is sucked by a high-speed refrigerant flow discharged from the nozzle portion, a mixing portion (FIG. 13c ), in which the refrigerant discharged from the nozzle portion and the refrigerant sucked from the refrigerant suction port are mixed, and a diffuser portion (FIG. 13d ) which increases a pressure of the mixed refrigerant from the mixing section; an evaporator ( 17 ) which vaporizes the refrigerant and discharges the vaporized refrigerant to the refrigerant suction port; a pressure anomaly detection device ( 23 , S2) which detects a pressure abnormality of a high-pressure refrigerant upstream of the nozzle portion; and a reduction device ( 16a ) for reducing a pressure increasing amount of the mixed refrigerant in the diffuser portion of the ejector, wherein the compressor sucks the refrigerant downstream of the ejector, and wherein when the pressure abnormality detecting means detects the pressure abnormality, the reducing means a pressure increasing amount of the mixed refrigerant in the diffuser portion against a normal pressure state of the high pressure refrigerant reduced. Ejector refrigerant cycle device according to claim 11, wherein the pressure anomaly detecting means the pressure anomaly detected when the pressure of the refrigerant upstream of the nozzle section higher than is a predetermined value. Control method of an ejector-type refrigeration cycle device with an ejector ( 13 ) having a nozzle section ( 13a ) for reducing a pressure of a high-pressure refrigerant, a refrigerant suction port ( 13b ) from which a refrigerant from an evaporator ( 17 is sucked by a high-speed refrigerant flow discharged from the nozzle portion, a mixing portion (FIG. 13c ), in which the refrigerant discharged from the nozzle portion and the refrigerant sucked from the refrigerant suction port are mixed, and a diffuser portion (FIG. 13d ), which increases a pressure of the mixed refrigerant from the mixing portion, the method comprising: detecting a pressure abnormality of the high-pressure refrigerant upstream of the nozzle portion; and reducing a pressure increase amount of the mixed refrigerant in the diffuser portion from a normal pressure state of the high pressure refrigeration means. A control method according to claim 13, wherein said Reduce by increasing one in the evaporator having a refrigerant outlet with the refrigerant suction port of the Ejector pump has connected, flowing Refrigerant charge greater than that is performed in the normal pressure state of the high-pressure refrigerant.